Economics Essay Example | Topics and Well Written Essays - 750 words - 2

Economics - Essay Example This way corn serves a two-way purpose and that will definitely increase its demand. Corn and soybean are considered as substitutes and according to economic theory if demand for a product raises then the demand for its substitute will obviously decline. Following this principle the price of the soybean will decline. Again corn and soybean shares the same habitat for production, especially the prime raw material for any agricultural production the land. Now an increased demand for corn will also lead to a higher price for the same, since price and demand are directly correlated. A product that is offering higher price will definitely translate into higher profit for the producer and an immediate shift from production of soybean to that of corn. Higher percentage of land and effort will now be directed towards corn production than that of soybean (Pearce, 2006). The above discussion seems economically sound, however a careful investigation might reveal that this holds for short run. O nce the producer starts to devote more land and other raw materials to the production of corn, corn production will rise and production of soybean will fall. Hence in long run owing to higher supply of corn its price will come down and that of soybean will go up as it is scarce now. These points to the fact that in long run an eventual equilibrium will be reached where both will be produced at an optimum level for the economy. Last but not the least since, energy has an ever increasing demand, hence if corn can project itself as a viable source of alternative energy in long run that have enough potential to replace fossil fuels then the trend for substituting soybean production land and raw material in favor of the corn might show a sustained trend, with soybean production looking for an alternative way as itself is a nutritious and valuable food source along with a rich source for food oil. It is obvious that since there is high need of alternative form of energy and that especiall y of bio fuel; corn oil as an important source of bio fuel will enjoy this boom in demand and price for this product will go up. The magnitude of this rise in price is subject to much debate. First of all if demand for a product is matched by its supply then the rise in price is minimal or zero. However if this is not the scenario that is there is excess demand then the price will go up. Interestingly it is worth noting that in case of excess supply the price might also go down even courting a rise in demand for the concerned product. The excess supply often follows a rise in demand owing to the behavioural pattern of the producer who might over estimate the rise in demand and increase his supply of corn in tune of his expectations. Apart from this demand-supply interaction, many other factors do operate while determining the fate of the corn oil. If people are well aware of the potential that corn oil holds as a fuel and alternative source of energy that will definitely translate i nto higher demand. Again this has to be also undertaken into the realm of analysis that whether any other form of substitutes to corn oil does exist, that might be cheaper, easily available in plenty and better source of energy. As a viable source of alternative energy in the long run corn oil will face quite a competition with Jatropha and Pongamia pinnata (Bridgewater, Halford and Karp, 2010, p. 236) and that outcome will

Importance of Examinations Essay Example for Free

Importance of Examinations Essay The world Examination is noun of the word examine. It means to test in order to verify, to judge and to certify, certain facts. Examination is a very wide word, which is used in all spheres of life. The learned examiner does not want that sense of examination to be discussed. He has in his mind the University Examination and he wants to know whether the institution of Examination should continue or should be abolished. Some persons are of opinion that examination is not the sure test of the ability of a candidate. The present examina ­tion system is based on cramming and to pass the examina ­tion has become more a matter of chance than that of abil ­ity. Again, the present system of examination promotes other evils such as copying and even corruption. The violent acci ­dents in the examination halls strengthen this claim. Even today we are told that a third-year student in one of the centers in Delhi gave a sound beating to an invigilator who objected that the candidate should not copy. The pity of the incident is that a police constable was in league with that candidate and he brought the material for him to be copied. Again, how can, the ability of a student be checked by a few questions? The answer to it is certainly in the negative. Thus, there is a strong case that it should be abolished. There are others who think that examination is a must. How can we do without an examination? Life in itself is a big examination. At every footstep we have to face certain tests. The success is always marked with dignity and honor in all the examinations of life. Examinations add to our abil ­ity, power of toleration, perseverance and other good quali ­ties. They think that examination is not only necessary but it is also a blessing. Everybody has been afraid of examinations. Even Lord Christ once uttered, May God not put anybody to test. Teachers, students, examiners and examinees, all think that examination is a curse, a horror and a terror. Most of the mental diseases among the students are the outcome of the examination and cramming. Inspite of all this, there must be something to mark the standards and to judge the ability of the candidates. The students are being led astray. They only study because they fear examinations. If this institution is abolished, it is certain they will not study even a word. Thus, we must assume that the system of examination should not be abolished, but it should be reformed so that it should be of a great advantage both to the student community and the society. The examination is an evil but it is necessary, therefore, it cannot be abolished. We cannot do without examinations, but the system needs a total reform. We should not follow the old orthodox methods, but the scientific change should be brought in the system of examinations.

Antidepressants for Postnatal Depression

Antidepressants for Postnatal Depression Antidepressants are they a safe and effective choice for the treatment of postnatal depression? This review assessed the evidence concerning the effectiveness and safety of antidepressants in the management of postnatal depression. This would facilitate evidence-based clinical decisions in the treatment of patients. Data was sourced from several electronic Athens-based and free databases covering the psycho-biomedical and nursing literature. Studies found included randomised clinical trials, case- and cohort-controlled studies, questionnaire surveys, and qualitative/exploratory research. Previous reviews were also appraised. Outcomes from over 1200 mothers, mother-infant pairings, or infants, exposed to antidepressants were considered. Antidepressants appear to significantly alleviate depressive symptoms. Furthermore, the reported side effects are generally benign and clinically insignificant. However, methodological and analytic flaws negate conclusive inferences. Many studies fail to account for important covariates that may explain effects attributed to antidepressants. Furthermore, most studies fail to account for interactions between antidepressants and patient characteristics, which may reveal more severe adverse effects. Additionally, there is a paucity of literature on long-term effects. Finally, a lack of randomised clinical trials precludes inferences of causality. Given these constraints it is recommended that antidepressants are used as a last resort, and patients are closely monitored to identify unexpected side effects, or recovery induced by covariates rather than antidepressants. Chapter One Introduction, Rationale, AIMS Introduction According to Beckford-ball (2000) postnatal depression (PND) fails to attract public attention because it is associated with a positive event – childbirth – notwithstanding the evidence that a sizeable majority of women experience this phenomenon after delivering their baby (RCP , 2004). Nevertheless postnatal depression, if left untreated, can have adverse effects for mother-child relationship and infant development (Green, 1995). This brief reviews evidence concerning the safety and effectiveness of antidepressants for treating postnatal depression. It is argued that while antidepressants may alleviate depressive symptoms, with benign side effects, various methodological and analytic constraints in the literature negate conclusive inferences on the subject. Antidepressants According to the RCP antidepressants are drugs developed in the 1950s for treating symptoms of depression (RCP, 2006).They work by stimulating neurotransmitters in the brain. Three main types of antidepressants are specified: 1. Tricyclic’s (TCAs): amitriptyline, imipramine, nortriptyline. 2. Selective Serotonin Reuptake Inhibitors (SSRIs): sertraline, paroxetine, fluoxetine, citalopram, venlafaxine, moclobemide. 3. Serotonin and Noradrenaline Reuptake Inhibitors (SNRIs): venlafaxine, reboxetine. 4. Monoamine Oxidase Inhibitors (MAOIs): tranylcypromine, moclobemide, phenelzine. The RCP posits that following three months of treatment 50% to 65%of people given an antidepressant show improvements in mood, compared with 25% to 30% of people administered a placebo. Thus, even after accounting for placebo effects, antidepressants still facilitate further recovery from depressive symptoms. TCAs are generally older than SSRIs and are considered to produce more side effects, especially if there is an overdose. However, all four classes of antidepressants are considered to have by-products, such as high blood pressure, anxiety, indigestion, dry mouth, heart tremor, and sleepiness. Most of the adverse effects are considered mild and expected to dissipate after few weeks. The RCP cites evidence of withdrawal symptoms in infants shortly after birth, especially with paroxetine (RCP, 2006). Babies can also receive a minute concentration of antidepressants via breastfeeding (Kohen,2005), albeit the risk of pathology is considered small due to the rapid development of kidneys and livers in infants. Overall, use of antidepressants during breastfeeding is not discouraged. Some pregnant women suffer a recurrence of depressive symptoms, and therefore may need to take antidepressants continually. The National Institute for Clinical Excellence (NICE, 2004) has published guidelines for the treatment of depression. However, there is no special emphasis on pregnancy-related depression. Antenatal and postnatal guidelines are due to be published by 2007 (Green, 2005). Postnatal Depression According to the RCP (2004) postnatal depression (PND) â€Å"is what happens when you become depressed after having a baby† (p.1). It is quite common, affecting circa 10% of newly delivered mothers, and can last for several months or longer if untreated. Symptoms include feeling depressed (unhappy, low, wretched, with symptoms becoming worse at particular times of the day), irritable(heightened sensitivity, especially to benign comments by others),tiredness, sleeplessness (late retirements, early rises), and lack of appetite and interest in sexual intercourse. Many women may feel they are unable to cope with the new situation, or even experience anxiety and detachment towards the infant. Various causes of PND have been identified including a previous history of depression, not having a supportive partner, having a sick infant or premature delivery, losing one’s own mother as a child, and stressful life events (e.g. bereavement, divorce, financial problems) within a short time scale. PND has also been associated with hormonal changes. PND appears to progress through several stages (Beckford-Ball, 2000; Green, 2005): 1. Postpartum ‘blues’; 2. Postnatal depression; 3. Puerperal psychosis. Postpartum ‘blues’ â€Å"is usually a transient phase occurring 3-5 days after the birth of the child, with few or no psychiatric symptoms. This stage is characterised by mood swings, tearfulness, fatigue, lack of concentration, confusion, anxiety and hostility† (p.126). This condition is easily treated using hormone replacement therapy. Postnatal depression is less frequent, and emerges as a deep and protracted ‘sadness’ which â€Å"is much more intense and persistent than postpartum blues and its symptoms rarely subside without help† (p.126).Many mothers may feel insecure, incompetent, irritable, guilty (about feeling sad following a happy event), weight changes, insomnia/hypersomnia, psychomotor retardation/agitation, tiredness, and loss of interest in activities. This condition often results in hospitalisation and treatment with antidepressants and cognitive-behavioural counselling. Puerperal psychosis is a severe mood disorder typified by delusions and hallucinations. This condition is considered a psychiatric emergency, necessitating admission to a psychiatric institution and treatment with antidepressants and other drugs. Rationale Despite clear guidelines regarding the use of antidepressants during pregnancy it is necessary to appraise existing literature on the topic, for several reasons: 1. Limited scope of existing reviews. 2. Identification of gaps and inconsistencies in the literature 3. Verification of current claims and guidelines, for example by the RCP, regarding the management of postnatal depression. Limited scope Previous literature reviews are considered in this brief (see Chapter 3). Most reviews are limited in scope mainly because they focus on studies using a particular research methodology(e.g. Booth et al, 2005), mother-child transmission through breastfeeding (e.g. Cohen, 2005), and effects on depressive symptoms(e.g. Hendricks, 2003; Bennett et al, 2004). Thus, there is a need for an all-inclusive review that offers a broader insight into current literature. Identification of gaps and inconsistencies Previous reviews on the topic have highlighted problems that need to be addressed in future research. However each review is different and new research findings continually emerge that may have implications for previous reviews. For example, past reviews have found little evidence of malformations resulting from SSRI use (e.g. Booth et al, 2005). However, new concerns are starting to emerge regarding various analytic and methodological constraints that negate conclusive inferences about the safety of SSRIs. Verification of current claims The RCP publishes an information guide for the use of antidepressants. Various claims are made regarding safety and efficacy of use during/after pregnancy, consistent with NICE(2004) standards. While most assertions are based on research evidence there is a need for on-going reviews that highlight recent findings and consider their implications for existing guidelines. Some of the key pronouncements and guidelines are as follows: 1. People who take antidepressants show a significant improvement over persons administered a placebo. 2. TCAs and SSRIs are equally effective but the latter (newer drug) is safer because it seems to have fewer side effects. 3. MAOIs can induce high blood pressure given certain (dietary) conditions 4. Babies whose mothers take antidepressants (especially paroxetine) may experience adverse effects. 5. It is best to carry on taking antidepressants while breastfeeding, since only minute amounts will be transferred to the baby. Livers and kidneys develop rapidly in babies only a few weeks old, helping to breakdown and filter antidepressants in the bloodstream. Aim The aim of the current review was to appraise evidence on the safety and effectiveness of antidepressants in the management of PND. Chapter Two Literature Review The evidence/data to be reviewed here is based on a comprehensive search of multiple databases including HIGHWIRE Press, ACADEMIC SEARCH PREMIER (access through EBSCO databases), Psych INFO, INTERNURSE, and the BRITISH MEDICAL JOURNAL database. The Internet was also searched with emphasis on peer-reviewed published journal articles. Key words included: ‘antidepressants’, ‘depression’, and ‘postnatal depression’. There were no problems of access: all the databases reviewed are available to the general public through university library resources and/or Athens protected resources. These particular databases were chosen because of their emphasis on psychological, biomedical, and practice-based literature, and easier access to full-text files. For example, Psych INFO contains more than1,500,000 references to journal articles, books, technical reports, and dissertations, published in numerous countries. As a form of psychopathology, PND is comprehensively addressed. INTERNURSE provides access specifically to the nursing literature and incorporates may key journals (e.g. British Journal of Nursing, Nurse Prescribing, Practice Nursing, and the International Journal of Palliative Nursing). HIGHWIRE Press is one of the two largest archives of free full-text science databases available, providing access to thousands of psych biomedical journal articles and books. ACADEMIC SEARCH PREMIER incorporates over4000 scholarly journals and 3100 peer review articles. These databases were preferred to others such as SCIENCE DIRECT, have a more general emphasis on scientific (rather than clinical, medical) literature, or not provide sufficient access to full-text articles. Only studies that satisfied the following criteria were eligible to be reviewed: 1. Empirical studies using either qualitative or quantitative methods. Thus, this included case studies, questionnaire surveys, retrospective/prospective designs, and randomised controlled trials(RCT). 2. Review articles and meta-analysis, including Cochrane reviews. 3. Focus on the effects of antidepressants on mother and/or child, and with or without breast-feeding. 4. Focus on postnatal depression, at any stage (i.e. postpartum ‘blues’, depression, and puerperal psychosis [Beckford-Ball, 2000]). 5. Focus on mothers perceptions of antidepressants as treatment for postnatal depression. The review also considered bits of literature published by the Department of Health (DOH), National Institute of Clinical Excellence(NICE), and the Royal College of Psychiatrists (RCP). The emphasis was on the role of SSRIs and TCAs albeit some literature on MAOIs and SNRIs was also considered. Individual studies are reviewed first, followed by review articles. Value of conducting a literature review The safety and effectiveness of antidepressants can easily be established by conducting an original empirical study. However, individual studies are severely constrained in scope and will ultimately provide a ‘snap-shot ‘or ‘localised’ insight on the subject. Moreover, scientific knowledge advances from the accumulation of evidence rather than the results of isolated studies, except in cases where there is a virtually no research on a topic, so that the findings of individual studies assume greater importance. Depression as a topic has been heavily researched. Numerous studies have been published on antidepressants and PND. The multiplicity of published literature reviews on antidepressants/PND attests to the abundance of empirical evidence on the topic. Thus, attempting to establish the safety and efficacy of antidepressants on the basis of a single study would still require an understanding of what has been done before and current knowledge on the topic. Otherwise the researcher is in danger of merely reinventing the wheel. Thus, proper scientific protocol dictates that the researcher first begins by reviewing the literature, in order to get a bird’s eye view of the available evidence, identify gaps in the literature, and highlight avenues for further research (Cool can, 1994). Effects of anti-depressants Appleby et al (1997) conducted a randomised control trial to assess the effects of fluoxetine and cognitive-behavioural counselling on postnatal depression. Another aim was to compare fluoxetine and placebo groups, and also drug combinations and counselling. Hitherto there had been a paucity of randomised clinical trials in this area. Appleby et al (1997) question the clinical benefits of using antidepressants, given that prognosis for PND is often good, despite concerns about over-sedation, and other considerations. The study aimed to establish the optimal treatment frond. The antidepressant of interest was the SSRI, fluoxetine. Participants were women identified at an urban health district(Manchester) as being depressed 6-8 weeks post childbirth. They completed the EPDS , and those with sufficiently high scores were interviewed using a revised clinical schedule, to identify cases of significant psychiatric depression. Women with a prior history of depression, substance abuse, severe illness that required hospitalisation, or breastfeeding, were excluded. Participants were randomly assigned to one of four experimental conditions: fluoxetine, placebo, one counselling session, and six counselling sessions. Mood assessments took place at 1, 4, and 12 weeks post-intervention, using the revised interview schedule, EPDS, and Hamilton depression scale. Data was analysed using analysis of variance for repeated measures (to account for the multiple outcome variables).Overall, 188 verified cases of PND were identified, from a sample of2978 women eligible to participate. Of these, 87 took part in the clinical trial. Results revealed significant improvements in all four treatment groups. Fluoxetine produced better improvement compared with the placebo: the percentage (geometric) differences in means scores based on the revised clinical interview schedule was 37.1% (at 4 weeks)and 40.7% (12 weeks). The effect of fluoxetine was not moderated by(i.e. did not interact with) counselling. Improvements in mood occurred within one week of participating in the clinical trial. The authors concluded â€Å"this study shows the effectiveness of both fluoxetine and cognitive-behavioural counselling in the treatment of women found by community based screening to be depressed 6-8 weeks after childbirth† (p.932). The use of a classic experimental design(RCT) permits causal inferences about the impact of an antidepressant. However, the analysis failed to control for potential confounding variables. While Appleby et al (1997) took steps to eliminate extraneous variance, through strict eligibility criteria, it would have been useful to incorporate detailed background information in the analysis (e.g. availability of social support, marital relationship, stressful life events, side-effect profile, history of drug compliance, patient preference [Green, 2005]) to demonstrate the statistical significance of these variables, and the unique contribution of SSRI treatment after controlling for covariates. Thus, analysis of covariance would have been a more appropriate test. Nolan et al (1997) assessed the effect of TCA and SSRI drugs on feta neurodevelopment. The study compared children of mothers who had been prescribed a tricyclic antidepressant during pregnancy, mothers who had taken fluoxetine during pregnancy, and mothers who had not taken antidepressants. Outcomes measures comprised global IQ and language development, assessed from 16 to 18 months postnatal, using age-specific Bailey Scales of Infant Development, McCarthy Scales of Children’s Abilities (measures IQ), and the Rendell Developmental Language Scales. Results revealed no significant group differences in any of the outcome variables, suggesting that in utero ingestion of either TCAs or fluoxetine does not impair cognitive, linguistic, or behavioural development in infants. Null man et al (2002) conducted follow-up prospective controlled study assessing the effects of TCA and fluoxetine use throughout pregnancy on child development. Three groups of mother-child pairs were recruited. The first two groups were drawn from the Mothers Program, a scheme that provides support to women suffering from major depression. All women recruited from this programme had received counselling under the scheme, with either TCA Rossi (fluoxetine) treatment, which had been maintained throughout the duration of the pregnancy. A comparison group was also recruited that comprised women with no history of psychopathology, depression (based on the Centre for Epidemiological Studies Depression Scale [CES-D]), exposure to chemical or radiation pollution, or severe health problems likely to affect fatal development. This group was randomly selected from among visitors to the author’s clinic. Women who had discontinued the use of antidepressants after conception or during the pregnancy were not eligible to participate. Women were also excluded from the comparison group based on the same criteria applied to the Mothers groups. Outcome data was collected using the CES-D, antenatal and postnatal assessments, neurobehavioral tests (Bailey Scales of Infant Development, McCarthy Scales of Children’s Abilities, age-appropriate Achenbach Child Behaviour Checklist), and follow-up testing of them other (Wechsler Adult Intelligence Scale, and other measures). A one-way analysis of variance was used to compare outcome measures across the three groups. Correlational and regression tests were used to assess the contribution of confounding variables. Results revealed no group differences in child’s global IQ, language development, or behaviour (see Figure 1). The authors concluded, â€Å"Exposure to tricyclic antidepressants or fluoxetine throughout the gestation period does not appear to adversely affect cognition, language development, or the temperament of preschool and early-school children. Although regression was used to account for the contribution of confounding factors, such as verbal comprehension and expressive language, the variance explained by these variables was not in fact partial led out before testing for group differences. This would have required a multivariate analysis of covariance in which adjustments for covariates are built into the analysis. More importantly, the observed similarity in outcomes across the three groups may reflect simple or complex interactions with other variables. This issue is discussed in greater detail in Chapter 3. Figure 1 Cognitive outcomes (mental and psychomotor development, and cognitive abilities) across antidepressant and control groups(Nolan et al, 2002). Differences are not significant. Wisner et al (2001) performed a double-blind randomised control trial to assess the effect of nortriptyline on the rate of reoccurrence of postpartum depression in non-depressed women who had previously had at least one depressive episode. Women were randomly exposed tonortriptyline or a placebo immediately after childbirth. Outcome data was collected over a 5-month period using the Hamilton Rating Scale for Depression, and Research Diagnostic Criteria for depression. No group differences emerged, suggesting that nortriptyline was no more effective than a placebo in treating PND. This study was followed up with another RCT (Wisner et al, 2004), this time evaluating the effect of sertraline on the rate of and time to reoccurrence of postpartum depression. They highlighted a paucity of clinical trials on the impact of antidepressants in women who have previously had a depressive episode, and hence may be prone to experience a reoccurrence. Participants were pregnant women with gestation periods of 9 months or less, and at least one episode of postpartum depression that fits that the DSM-IV definition of major depression. Women with other forms of psychopathology (e.g. psychosis, or bipolar disorder) were excluded. Participants were randomly assigned to a treatment (sertraline) or placebo group. The drug was administered immediately after birth, beginning with a 50mg/day dose, which was later dropped to 25mg/day to minimise side effects (e.g. headache). Data analysis using Fisher’s exact test showed a significant group difference in rate of reoccurrences, during a 17-week preventive treatment period. Reoccurrences occurred in 4/8 women assigned to the placebo group, and1/14 women in the treatment condition, translating into a 0.43difference in reoccurrence rates. All women had adhered to the treatment regime, thus minimising the confounded effect of on-compliance. There was also a significant group difference in time to reoccurrence, with first reoccurrence beginning much earlier for the placebo group (at 5 weeks, followed by more reoccurrences) compared with the treatment group (at 17 weeks, followed by more reoccurrences). However, the treatment group reported more side effects (e.g. Dizziness, drowsiness). This RCT clearly demonstrates the effectiveness of an SSRI in preventing the reoccurrence of postpartum depression, albeit the conclusiveness of these findings is constrained by the failure to control for key background variables, such as previous and recent history of psychopathology, and drug effect expectations. For example, lingering symptoms of a distant depressive episode may help precipitate a quicker reoccurrence. Figure 2 Rate of recurrence of postpartum depression in placebo and SSRI women (Wisner et al, 2004) Oberlander et al (2005) tested the effect of SSRI exposure on bio behavioural responses to acute procedural pain in new-born babies at2 months of age. Previous research has suggested altered behavioural and physiological reactions to a routine painful event in infants, after prenatal exposure to SSRI antidepressants. There is paucity of literature on the long-term effects of SSRIs on neuro behavioural variables, such as cognitive, language and motor development. Given that SSRIs work by inhibiting the reuptake of serotonin(5-hydroxytrypamine [5HT], a neurotransmitter that regulates cardiovascular function and pain signals in the developing brain), and given that SSRIs easily pass through the placenta, it is possible that regions of the brain associated with pain reactivity may be affected. Participants were recruited from a cohort of mothers and their infants during pregnancy, as part of a longitudinal study of prenatal medication use. Only Mothers/infants with no psychotropic or antidepressant use during pregnancy, whose pregnancy was 9 to 10 weeks, and no history of maternal mental illness, were eligible to be assigned to the control group. Three groups of infants were compared: (a) infants exposed to prenatal SSRI (fluoxetine); (b) infants exposed postnatal via breastfeeding(paroxetine, fluoxetine, sertraline); and (c) control infants. Behavioural (facial activity), physiological (variations in heart rate[HR], often used as a measure of pain reactivity in infants), and pharmacological (analysis of blood and breast milk samples) data was collected. Results showed impaired facial reactions in infants exposed to prenatal SSRI. Altered pain reactivity was observed in both prenatal and postnatal exposed infants, suggesting enduring neuro behavioural SSRI effects that extend beyond the new-born phase. Oberlander et all’s(2005) study was constrained by low power and generalizability (limited sample size), and lack of a non-medicated control group with depressive symptomatology. They were uncertain about the clinical implications of these findings, suggesting that use of SSRIs for treating maternal depression was appropriate pending further research on the sustained effects of SSRIs. Marcus et al (2005) screened prenatal depression in pregnant women attending an obstetrics clinic. The study aimed to assess the rates faint-depressant use and its association with depression, measured byte Centre for Epidemiological Studies Depression Scale (CES-D).Overall, 390 women who had used antidepressants within two years of conception were screened. Average age was 28.6 years, and most women were married and Caucasian (73%). Screening took place at around 24gestation weeks. Data was collected regarding the use of antidepressants during the past two years, and discontinued use following pregnancy, in addition to the CES-D data. The standard CES-Duct-off of 16 was used to establish the presence of depressive symptomatology. A t-Test was used to compare two groups: women who reported they stopped using anti-depressants and hence were not currently on medication (n=248); and women who continued to use antidepressants during pregnancy (n=68). The dependent/outcome variable was total CES-Scores. Chi-square was also used to assess use/non-use of antidepressant medication and CES-D groupings (i.e. Figure 3 CES-D data for women who did and those who did not use antidepressants during pregnancy (Marcus et al, 2005). Observed differences are not significant. The authors attributed the null results to poor treatment adherence, and inadequate prescribing/monitoring. Furthermore, they suggested that group differences might have been more pronounced if the study focused on unmediated women (i.e. those who had not used antidepressants at all, rather discontinued use). This study was unique because it assessed antidepressant use around the time of conception. However, the findings are compromised by several analytic constraints. Firstly, these of a t-Test is questionable. This test makes no provision for controlling for covariates (i.e. important background variables, such as patient preference, compliance history, side-effect profile, social support, quality of marital relationship, prior history depression)that may confound significant group differences, although this concerns less important given the null results. A more serious problem is the possibility that certain assumptions which underlie use of the t-Test were violated, notably homogeneity of variance. The huge disparity in group sizes (268 versus 68) hugely increases the possibility of significant differences in group variances, which in turn would obscure reliable differences in CES-Scores. The authors do not report Levine test results, which would have addressed the homogeneity issue. Perhaps a non-parametric test (e.g. Mann-Whitney) may have been more appropriate. Furthermore, it is not clear why the authors conducted a chi-square test! Collapsing the CES-Scores into a dichotomy reduces the quality of the data because it obscures subtle differences between scores. Overall, the chi-square analyses amounted to a less precise duplication of the t-Test results! Finally, this study was entirely based on women’s self-reports of medication use, with no familial, clinical, or other verification. Its therefore unclear to what extent the null results are attributable to self-report bias. Several review articles on antidepressants and postnatal depression have been published. These range from limited commentaries (e.g. Goldstein Sun dell, 1999; Yoshida et al, 1999; Misery Kostas’s, 2002; Hendricks, 2003; Bennett et al, 2004; Cohen, 2005;Marcus et al, 2005) to comprehensive and systematic appraisals. Goldstein and Sun dell (1999) reviewed literature on the safety of SSRIs during pregnancy. Their work was based on the premise that although antidepressants may be necessary during pregnancy it is essential identify and weigh the risks against the benefits in order to make an informed choice as to whether or not to use the drugs. Due to the paucity of randomised controlled trials on the topic, the review focused on evidence obtained from cohort/case-controlled studies, patient surveys, retrospective studies, and anecdotal reports. Electronic databases searched included Medline, EMBASE, Daren’t Drug File, and Psych INFO. Four cohort-controlled and 5 prospective studies were found which evaluated the impact of SSRI exposure. One study compared fluoxetine, TCA, and non-teratogen (e.g. antibiotics) exposed groups of non-depressed females. SSRI and TCA exposure produced no significant malformations, or differences in birth weight and infant prematurity. However, there was a greater tendency for fluoxetine- and tricyclic-exposed women to miscarry compared with controls. However, this effect was not significant and hence may simply have occurred by chance. Goldstein and Sun dell (1999) report another study which compared early exposed (prior to 25 weeks), late exposed (continuing after 24 weeks),and a non-teratogen control group. Again findings revealed no adverse effects in the treatment groups, albeit infants exposed to fluoxetine early showed a higher prevalence of minor anomalies that have little or no clinical importance. Furthermore late exposure to fluoxetine seemed to increase the rates of admission to special care nurseries and impaired fatal development. However, these findings were inconclusive due to prior group differences on previous psychotropic drug use, and failure to control for depression levels. Still other research suggests no effect of SSRIs (sertraline) on the prevalence of stillbirth, prematurity, mean birth weight and gestational age. Evidence suggests no statistically significant differences between SSRI exposed and control groups on IQ, language development, height, and head circumference. Of the prospective studies reviewed three assessed paroxetine, and fluoxetine, and two tested sertraline. All studies reported no significant increase in the rate of malformations and spontaneous abortion, although there was some evidence of lower birth weight given protracted use of antidepressants. Goldstein and Sun dell (1999) found one study, which showed that fluoxetine exposure during the first trimester did not increase the risk of malformations Antidepressants for Postnatal Depression Antidepressants for Postnatal Depression Antidepressants are they a safe and effective choice for the treatment of postnatal depression? This review assessed the evidence concerning the effectiveness and safety of antidepressants in the management of postnatal depression. This would facilitate evidence-based clinical decisions in the treatment of patients. Data was sourced from several electronic Athens-based and free databases covering the psycho-biomedical and nursing literature. Studies found included randomised clinical trials, case- and cohort-controlled studies, questionnaire surveys, and qualitative/exploratory research. Previous reviews were also appraised. Outcomes from over 1200 mothers, mother-infant pairings, or infants, exposed to antidepressants were considered. Antidepressants appear to significantly alleviate depressive symptoms. Furthermore, the reported side effects are generally benign and clinically insignificant. However, methodological and analytic flaws negate conclusive inferences. Many studies fail to account for important covariates that may explain effects attributed to antidepressants. Furthermore, most studies fail to account for interactions between antidepressants and patient characteristics, which may reveal more severe adverse effects. Additionally, there is a paucity of literature on long-term effects. Finally, a lack of randomised clinical trials precludes inferences of causality. Given these constraints it is recommended that antidepressants are used as a last resort, and patients are closely monitored to identify unexpected side effects, or recovery induced by covariates rather than antidepressants. Chapter One Introduction, Rationale, AIMS Introduction According to Beckford-ball (2000) postnatal depression (PND) fails to attract public attention because it is associated with a positive event – childbirth – notwithstanding the evidence that a sizeable majority of women experience this phenomenon after delivering their baby (RCP , 2004). Nevertheless postnatal depression, if left untreated, can have adverse effects for mother-child relationship and infant development (Green, 1995). This brief reviews evidence concerning the safety and effectiveness of antidepressants for treating postnatal depression. It is argued that while antidepressants may alleviate depressive symptoms, with benign side effects, various methodological and analytic constraints in the literature negate conclusive inferences on the subject. Antidepressants According to the RCP antidepressants are drugs developed in the 1950s for treating symptoms of depression (RCP, 2006).They work by stimulating neurotransmitters in the brain. Three main types of antidepressants are specified: 1. Tricyclic’s (TCAs): amitriptyline, imipramine, nortriptyline. 2. Selective Serotonin Reuptake Inhibitors (SSRIs): sertraline, paroxetine, fluoxetine, citalopram, venlafaxine, moclobemide. 3. Serotonin and Noradrenaline Reuptake Inhibitors (SNRIs): venlafaxine, reboxetine. 4. Monoamine Oxidase Inhibitors (MAOIs): tranylcypromine, moclobemide, phenelzine. The RCP posits that following three months of treatment 50% to 65%of people given an antidepressant show improvements in mood, compared with 25% to 30% of people administered a placebo. Thus, even after accounting for placebo effects, antidepressants still facilitate further recovery from depressive symptoms. TCAs are generally older than SSRIs and are considered to produce more side effects, especially if there is an overdose. However, all four classes of antidepressants are considered to have by-products, such as high blood pressure, anxiety, indigestion, dry mouth, heart tremor, and sleepiness. Most of the adverse effects are considered mild and expected to dissipate after few weeks. The RCP cites evidence of withdrawal symptoms in infants shortly after birth, especially with paroxetine (RCP, 2006). Babies can also receive a minute concentration of antidepressants via breastfeeding (Kohen,2005), albeit the risk of pathology is considered small due to the rapid development of kidneys and livers in infants. Overall, use of antidepressants during breastfeeding is not discouraged. Some pregnant women suffer a recurrence of depressive symptoms, and therefore may need to take antidepressants continually. The National Institute for Clinical Excellence (NICE, 2004) has published guidelines for the treatment of depression. However, there is no special emphasis on pregnancy-related depression. Antenatal and postnatal guidelines are due to be published by 2007 (Green, 2005). Postnatal Depression According to the RCP (2004) postnatal depression (PND) â€Å"is what happens when you become depressed after having a baby† (p.1). It is quite common, affecting circa 10% of newly delivered mothers, and can last for several months or longer if untreated. Symptoms include feeling depressed (unhappy, low, wretched, with symptoms becoming worse at particular times of the day), irritable(heightened sensitivity, especially to benign comments by others),tiredness, sleeplessness (late retirements, early rises), and lack of appetite and interest in sexual intercourse. Many women may feel they are unable to cope with the new situation, or even experience anxiety and detachment towards the infant. Various causes of PND have been identified including a previous history of depression, not having a supportive partner, having a sick infant or premature delivery, losing one’s own mother as a child, and stressful life events (e.g. bereavement, divorce, financial problems) within a short time scale. PND has also been associated with hormonal changes. PND appears to progress through several stages (Beckford-Ball, 2000; Green, 2005): 1. Postpartum ‘blues’; 2. Postnatal depression; 3. Puerperal psychosis. Postpartum ‘blues’ â€Å"is usually a transient phase occurring 3-5 days after the birth of the child, with few or no psychiatric symptoms. This stage is characterised by mood swings, tearfulness, fatigue, lack of concentration, confusion, anxiety and hostility† (p.126). This condition is easily treated using hormone replacement therapy. Postnatal depression is less frequent, and emerges as a deep and protracted ‘sadness’ which â€Å"is much more intense and persistent than postpartum blues and its symptoms rarely subside without help† (p.126).Many mothers may feel insecure, incompetent, irritable, guilty (about feeling sad following a happy event), weight changes, insomnia/hypersomnia, psychomotor retardation/agitation, tiredness, and loss of interest in activities. This condition often results in hospitalisation and treatment with antidepressants and cognitive-behavioural counselling. Puerperal psychosis is a severe mood disorder typified by delusions and hallucinations. This condition is considered a psychiatric emergency, necessitating admission to a psychiatric institution and treatment with antidepressants and other drugs. Rationale Despite clear guidelines regarding the use of antidepressants during pregnancy it is necessary to appraise existing literature on the topic, for several reasons: 1. Limited scope of existing reviews. 2. Identification of gaps and inconsistencies in the literature 3. Verification of current claims and guidelines, for example by the RCP, regarding the management of postnatal depression. Limited scope Previous literature reviews are considered in this brief (see Chapter 3). Most reviews are limited in scope mainly because they focus on studies using a particular research methodology(e.g. Booth et al, 2005), mother-child transmission through breastfeeding (e.g. Cohen, 2005), and effects on depressive symptoms(e.g. Hendricks, 2003; Bennett et al, 2004). Thus, there is a need for an all-inclusive review that offers a broader insight into current literature. Identification of gaps and inconsistencies Previous reviews on the topic have highlighted problems that need to be addressed in future research. However each review is different and new research findings continually emerge that may have implications for previous reviews. For example, past reviews have found little evidence of malformations resulting from SSRI use (e.g. Booth et al, 2005). However, new concerns are starting to emerge regarding various analytic and methodological constraints that negate conclusive inferences about the safety of SSRIs. Verification of current claims The RCP publishes an information guide for the use of antidepressants. Various claims are made regarding safety and efficacy of use during/after pregnancy, consistent with NICE(2004) standards. While most assertions are based on research evidence there is a need for on-going reviews that highlight recent findings and consider their implications for existing guidelines. Some of the key pronouncements and guidelines are as follows: 1. People who take antidepressants show a significant improvement over persons administered a placebo. 2. TCAs and SSRIs are equally effective but the latter (newer drug) is safer because it seems to have fewer side effects. 3. MAOIs can induce high blood pressure given certain (dietary) conditions 4. Babies whose mothers take antidepressants (especially paroxetine) may experience adverse effects. 5. It is best to carry on taking antidepressants while breastfeeding, since only minute amounts will be transferred to the baby. Livers and kidneys develop rapidly in babies only a few weeks old, helping to breakdown and filter antidepressants in the bloodstream. Aim The aim of the current review was to appraise evidence on the safety and effectiveness of antidepressants in the management of PND. Chapter Two Literature Review The evidence/data to be reviewed here is based on a comprehensive search of multiple databases including HIGHWIRE Press, ACADEMIC SEARCH PREMIER (access through EBSCO databases), Psych INFO, INTERNURSE, and the BRITISH MEDICAL JOURNAL database. The Internet was also searched with emphasis on peer-reviewed published journal articles. Key words included: ‘antidepressants’, ‘depression’, and ‘postnatal depression’. There were no problems of access: all the databases reviewed are available to the general public through university library resources and/or Athens protected resources. These particular databases were chosen because of their emphasis on psychological, biomedical, and practice-based literature, and easier access to full-text files. For example, Psych INFO contains more than1,500,000 references to journal articles, books, technical reports, and dissertations, published in numerous countries. As a form of psychopathology, PND is comprehensively addressed. INTERNURSE provides access specifically to the nursing literature and incorporates may key journals (e.g. British Journal of Nursing, Nurse Prescribing, Practice Nursing, and the International Journal of Palliative Nursing). HIGHWIRE Press is one of the two largest archives of free full-text science databases available, providing access to thousands of psych biomedical journal articles and books. ACADEMIC SEARCH PREMIER incorporates over4000 scholarly journals and 3100 peer review articles. These databases were preferred to others such as SCIENCE DIRECT, have a more general emphasis on scientific (rather than clinical, medical) literature, or not provide sufficient access to full-text articles. Only studies that satisfied the following criteria were eligible to be reviewed: 1. Empirical studies using either qualitative or quantitative methods. Thus, this included case studies, questionnaire surveys, retrospective/prospective designs, and randomised controlled trials(RCT). 2. Review articles and meta-analysis, including Cochrane reviews. 3. Focus on the effects of antidepressants on mother and/or child, and with or without breast-feeding. 4. Focus on postnatal depression, at any stage (i.e. postpartum ‘blues’, depression, and puerperal psychosis [Beckford-Ball, 2000]). 5. Focus on mothers perceptions of antidepressants as treatment for postnatal depression. The review also considered bits of literature published by the Department of Health (DOH), National Institute of Clinical Excellence(NICE), and the Royal College of Psychiatrists (RCP). The emphasis was on the role of SSRIs and TCAs albeit some literature on MAOIs and SNRIs was also considered. Individual studies are reviewed first, followed by review articles. Value of conducting a literature review The safety and effectiveness of antidepressants can easily be established by conducting an original empirical study. However, individual studies are severely constrained in scope and will ultimately provide a ‘snap-shot ‘or ‘localised’ insight on the subject. Moreover, scientific knowledge advances from the accumulation of evidence rather than the results of isolated studies, except in cases where there is a virtually no research on a topic, so that the findings of individual studies assume greater importance. Depression as a topic has been heavily researched. Numerous studies have been published on antidepressants and PND. The multiplicity of published literature reviews on antidepressants/PND attests to the abundance of empirical evidence on the topic. Thus, attempting to establish the safety and efficacy of antidepressants on the basis of a single study would still require an understanding of what has been done before and current knowledge on the topic. Otherwise the researcher is in danger of merely reinventing the wheel. Thus, proper scientific protocol dictates that the researcher first begins by reviewing the literature, in order to get a bird’s eye view of the available evidence, identify gaps in the literature, and highlight avenues for further research (Cool can, 1994). Effects of anti-depressants Appleby et al (1997) conducted a randomised control trial to assess the effects of fluoxetine and cognitive-behavioural counselling on postnatal depression. Another aim was to compare fluoxetine and placebo groups, and also drug combinations and counselling. Hitherto there had been a paucity of randomised clinical trials in this area. Appleby et al (1997) question the clinical benefits of using antidepressants, given that prognosis for PND is often good, despite concerns about over-sedation, and other considerations. The study aimed to establish the optimal treatment frond. The antidepressant of interest was the SSRI, fluoxetine. Participants were women identified at an urban health district(Manchester) as being depressed 6-8 weeks post childbirth. They completed the EPDS , and those with sufficiently high scores were interviewed using a revised clinical schedule, to identify cases of significant psychiatric depression. Women with a prior history of depression, substance abuse, severe illness that required hospitalisation, or breastfeeding, were excluded. Participants were randomly assigned to one of four experimental conditions: fluoxetine, placebo, one counselling session, and six counselling sessions. Mood assessments took place at 1, 4, and 12 weeks post-intervention, using the revised interview schedule, EPDS, and Hamilton depression scale. Data was analysed using analysis of variance for repeated measures (to account for the multiple outcome variables).Overall, 188 verified cases of PND were identified, from a sample of2978 women eligible to participate. Of these, 87 took part in the clinical trial. Results revealed significant improvements in all four treatment groups. Fluoxetine produced better improvement compared with the placebo: the percentage (geometric) differences in means scores based on the revised clinical interview schedule was 37.1% (at 4 weeks)and 40.7% (12 weeks). The effect of fluoxetine was not moderated by(i.e. did not interact with) counselling. Improvements in mood occurred within one week of participating in the clinical trial. The authors concluded â€Å"this study shows the effectiveness of both fluoxetine and cognitive-behavioural counselling in the treatment of women found by community based screening to be depressed 6-8 weeks after childbirth† (p.932). The use of a classic experimental design(RCT) permits causal inferences about the impact of an antidepressant. However, the analysis failed to control for potential confounding variables. While Appleby et al (1997) took steps to eliminate extraneous variance, through strict eligibility criteria, it would have been useful to incorporate detailed background information in the analysis (e.g. availability of social support, marital relationship, stressful life events, side-effect profile, history of drug compliance, patient preference [Green, 2005]) to demonstrate the statistical significance of these variables, and the unique contribution of SSRI treatment after controlling for covariates. Thus, analysis of covariance would have been a more appropriate test. Nolan et al (1997) assessed the effect of TCA and SSRI drugs on feta neurodevelopment. The study compared children of mothers who had been prescribed a tricyclic antidepressant during pregnancy, mothers who had taken fluoxetine during pregnancy, and mothers who had not taken antidepressants. Outcomes measures comprised global IQ and language development, assessed from 16 to 18 months postnatal, using age-specific Bailey Scales of Infant Development, McCarthy Scales of Children’s Abilities (measures IQ), and the Rendell Developmental Language Scales. Results revealed no significant group differences in any of the outcome variables, suggesting that in utero ingestion of either TCAs or fluoxetine does not impair cognitive, linguistic, or behavioural development in infants. Null man et al (2002) conducted follow-up prospective controlled study assessing the effects of TCA and fluoxetine use throughout pregnancy on child development. Three groups of mother-child pairs were recruited. The first two groups were drawn from the Mothers Program, a scheme that provides support to women suffering from major depression. All women recruited from this programme had received counselling under the scheme, with either TCA Rossi (fluoxetine) treatment, which had been maintained throughout the duration of the pregnancy. A comparison group was also recruited that comprised women with no history of psychopathology, depression (based on the Centre for Epidemiological Studies Depression Scale [CES-D]), exposure to chemical or radiation pollution, or severe health problems likely to affect fatal development. This group was randomly selected from among visitors to the author’s clinic. Women who had discontinued the use of antidepressants after conception or during the pregnancy were not eligible to participate. Women were also excluded from the comparison group based on the same criteria applied to the Mothers groups. Outcome data was collected using the CES-D, antenatal and postnatal assessments, neurobehavioral tests (Bailey Scales of Infant Development, McCarthy Scales of Children’s Abilities, age-appropriate Achenbach Child Behaviour Checklist), and follow-up testing of them other (Wechsler Adult Intelligence Scale, and other measures). A one-way analysis of variance was used to compare outcome measures across the three groups. Correlational and regression tests were used to assess the contribution of confounding variables. Results revealed no group differences in child’s global IQ, language development, or behaviour (see Figure 1). The authors concluded, â€Å"Exposure to tricyclic antidepressants or fluoxetine throughout the gestation period does not appear to adversely affect cognition, language development, or the temperament of preschool and early-school children. Although regression was used to account for the contribution of confounding factors, such as verbal comprehension and expressive language, the variance explained by these variables was not in fact partial led out before testing for group differences. This would have required a multivariate analysis of covariance in which adjustments for covariates are built into the analysis. More importantly, the observed similarity in outcomes across the three groups may reflect simple or complex interactions with other variables. This issue is discussed in greater detail in Chapter 3. Figure 1 Cognitive outcomes (mental and psychomotor development, and cognitive abilities) across antidepressant and control groups(Nolan et al, 2002). Differences are not significant. Wisner et al (2001) performed a double-blind randomised control trial to assess the effect of nortriptyline on the rate of reoccurrence of postpartum depression in non-depressed women who had previously had at least one depressive episode. Women were randomly exposed tonortriptyline or a placebo immediately after childbirth. Outcome data was collected over a 5-month period using the Hamilton Rating Scale for Depression, and Research Diagnostic Criteria for depression. No group differences emerged, suggesting that nortriptyline was no more effective than a placebo in treating PND. This study was followed up with another RCT (Wisner et al, 2004), this time evaluating the effect of sertraline on the rate of and time to reoccurrence of postpartum depression. They highlighted a paucity of clinical trials on the impact of antidepressants in women who have previously had a depressive episode, and hence may be prone to experience a reoccurrence. Participants were pregnant women with gestation periods of 9 months or less, and at least one episode of postpartum depression that fits that the DSM-IV definition of major depression. Women with other forms of psychopathology (e.g. psychosis, or bipolar disorder) were excluded. Participants were randomly assigned to a treatment (sertraline) or placebo group. The drug was administered immediately after birth, beginning with a 50mg/day dose, which was later dropped to 25mg/day to minimise side effects (e.g. headache). Data analysis using Fisher’s exact test showed a significant group difference in rate of reoccurrences, during a 17-week preventive treatment period. Reoccurrences occurred in 4/8 women assigned to the placebo group, and1/14 women in the treatment condition, translating into a 0.43difference in reoccurrence rates. All women had adhered to the treatment regime, thus minimising the confounded effect of on-compliance. There was also a significant group difference in time to reoccurrence, with first reoccurrence beginning much earlier for the placebo group (at 5 weeks, followed by more reoccurrences) compared with the treatment group (at 17 weeks, followed by more reoccurrences). However, the treatment group reported more side effects (e.g. Dizziness, drowsiness). This RCT clearly demonstrates the effectiveness of an SSRI in preventing the reoccurrence of postpartum depression, albeit the conclusiveness of these findings is constrained by the failure to control for key background variables, such as previous and recent history of psychopathology, and drug effect expectations. For example, lingering symptoms of a distant depressive episode may help precipitate a quicker reoccurrence. Figure 2 Rate of recurrence of postpartum depression in placebo and SSRI women (Wisner et al, 2004) Oberlander et al (2005) tested the effect of SSRI exposure on bio behavioural responses to acute procedural pain in new-born babies at2 months of age. Previous research has suggested altered behavioural and physiological reactions to a routine painful event in infants, after prenatal exposure to SSRI antidepressants. There is paucity of literature on the long-term effects of SSRIs on neuro behavioural variables, such as cognitive, language and motor development. Given that SSRIs work by inhibiting the reuptake of serotonin(5-hydroxytrypamine [5HT], a neurotransmitter that regulates cardiovascular function and pain signals in the developing brain), and given that SSRIs easily pass through the placenta, it is possible that regions of the brain associated with pain reactivity may be affected. Participants were recruited from a cohort of mothers and their infants during pregnancy, as part of a longitudinal study of prenatal medication use. Only Mothers/infants with no psychotropic or antidepressant use during pregnancy, whose pregnancy was 9 to 10 weeks, and no history of maternal mental illness, were eligible to be assigned to the control group. Three groups of infants were compared: (a) infants exposed to prenatal SSRI (fluoxetine); (b) infants exposed postnatal via breastfeeding(paroxetine, fluoxetine, sertraline); and (c) control infants. Behavioural (facial activity), physiological (variations in heart rate[HR], often used as a measure of pain reactivity in infants), and pharmacological (analysis of blood and breast milk samples) data was collected. Results showed impaired facial reactions in infants exposed to prenatal SSRI. Altered pain reactivity was observed in both prenatal and postnatal exposed infants, suggesting enduring neuro behavioural SSRI effects that extend beyond the new-born phase. Oberlander et all’s(2005) study was constrained by low power and generalizability (limited sample size), and lack of a non-medicated control group with depressive symptomatology. They were uncertain about the clinical implications of these findings, suggesting that use of SSRIs for treating maternal depression was appropriate pending further research on the sustained effects of SSRIs. Marcus et al (2005) screened prenatal depression in pregnant women attending an obstetrics clinic. The study aimed to assess the rates faint-depressant use and its association with depression, measured byte Centre for Epidemiological Studies Depression Scale (CES-D).Overall, 390 women who had used antidepressants within two years of conception were screened. Average age was 28.6 years, and most women were married and Caucasian (73%). Screening took place at around 24gestation weeks. Data was collected regarding the use of antidepressants during the past two years, and discontinued use following pregnancy, in addition to the CES-D data. The standard CES-Duct-off of 16 was used to establish the presence of depressive symptomatology. A t-Test was used to compare two groups: women who reported they stopped using anti-depressants and hence were not currently on medication (n=248); and women who continued to use antidepressants during pregnancy (n=68). The dependent/outcome variable was total CES-Scores. Chi-square was also used to assess use/non-use of antidepressant medication and CES-D groupings (i.e. Figure 3 CES-D data for women who did and those who did not use antidepressants during pregnancy (Marcus et al, 2005). Observed differences are not significant. The authors attributed the null results to poor treatment adherence, and inadequate prescribing/monitoring. Furthermore, they suggested that group differences might have been more pronounced if the study focused on unmediated women (i.e. those who had not used antidepressants at all, rather discontinued use). This study was unique because it assessed antidepressant use around the time of conception. However, the findings are compromised by several analytic constraints. Firstly, these of a t-Test is questionable. This test makes no provision for controlling for covariates (i.e. important background variables, such as patient preference, compliance history, side-effect profile, social support, quality of marital relationship, prior history depression)that may confound significant group differences, although this concerns less important given the null results. A more serious problem is the possibility that certain assumptions which underlie use of the t-Test were violated, notably homogeneity of variance. The huge disparity in group sizes (268 versus 68) hugely increases the possibility of significant differences in group variances, which in turn would obscure reliable differences in CES-Scores. The authors do not report Levine test results, which would have addressed the homogeneity issue. Perhaps a non-parametric test (e.g. Mann-Whitney) may have been more appropriate. Furthermore, it is not clear why the authors conducted a chi-square test! Collapsing the CES-Scores into a dichotomy reduces the quality of the data because it obscures subtle differences between scores. Overall, the chi-square analyses amounted to a less precise duplication of the t-Test results! Finally, this study was entirely based on women’s self-reports of medication use, with no familial, clinical, or other verification. Its therefore unclear to what extent the null results are attributable to self-report bias. Several review articles on antidepressants and postnatal depression have been published. These range from limited commentaries (e.g. Goldstein Sun dell, 1999; Yoshida et al, 1999; Misery Kostas’s, 2002; Hendricks, 2003; Bennett et al, 2004; Cohen, 2005;Marcus et al, 2005) to comprehensive and systematic appraisals. Goldstein and Sun dell (1999) reviewed literature on the safety of SSRIs during pregnancy. Their work was based on the premise that although antidepressants may be necessary during pregnancy it is essential identify and weigh the risks against the benefits in order to make an informed choice as to whether or not to use the drugs. Due to the paucity of randomised controlled trials on the topic, the review focused on evidence obtained from cohort/case-controlled studies, patient surveys, retrospective studies, and anecdotal reports. Electronic databases searched included Medline, EMBASE, Daren’t Drug File, and Psych INFO. Four cohort-controlled and 5 prospective studies were found which evaluated the impact of SSRI exposure. One study compared fluoxetine, TCA, and non-teratogen (e.g. antibiotics) exposed groups of non-depressed females. SSRI and TCA exposure produced no significant malformations, or differences in birth weight and infant prematurity. However, there was a greater tendency for fluoxetine- and tricyclic-exposed women to miscarry compared with controls. However, this effect was not significant and hence may simply have occurred by chance. Goldstein and Sun dell (1999) report another study which compared early exposed (prior to 25 weeks), late exposed (continuing after 24 weeks),and a non-teratogen control group. Again findings revealed no adverse effects in the treatment groups, albeit infants exposed to fluoxetine early showed a higher prevalence of minor anomalies that have little or no clinical importance. Furthermore late exposure to fluoxetine seemed to increase the rates of admission to special care nurseries and impaired fatal development. However, these findings were inconclusive due to prior group differences on previous psychotropic drug use, and failure to control for depression levels. Still other research suggests no effect of SSRIs (sertraline) on the prevalence of stillbirth, prematurity, mean birth weight and gestational age. Evidence suggests no statistically significant differences between SSRI exposed and control groups on IQ, language development, height, and head circumference. Of the prospective studies reviewed three assessed paroxetine, and fluoxetine, and two tested sertraline. All studies reported no significant increase in the rate of malformations and spontaneous abortion, although there was some evidence of lower birth weight given protracted use of antidepressants. Goldstein and Sun dell (1999) found one study, which showed that fluoxetine exposure during the first trimester did not increase the risk of malformations

Yersinia pestis :: Biology Biological Health Medical Essays

Yersinia pestis Life History Yersinia pestis is the causative agent of the systemic invasive infectious disease often referred to as the plague. The Y. pestis is an extremely virulent pathogen that is likely to cause severe illness and death upon infection unless antibiotics are administered. In the past, Y. pestis has caused devastating epidemics during three periods of modern history; the Justinian Plague spread from the Middle East to the Mediterranean during the 6th-8th centuries AD and killed approximately 25% of the population below the Alps region. Perhaps the most famous incidence of any disease was the devastating Black Plague of 8th-14th century Europe that eradicated 25 million people (nearly 25% of the population) and marked the end of the Dark Ages. The third endemic began in 1855 in China and was responsible for millions of deaths. Microbiological Characteristics Yersinia pestis is a Gram-negative, bipolar-staining coccobacillus member of the Enterobacteriaceae family, and is an obligate intracellular pathogen that must be contained within the blood to survive. It is also a fermentative, motile organism that produces a thick anti-phagocytic slime layer in its path. Transmission Y. pestis has the ability to cause disease in rodents, insects and humans. The primary carriers of the pathogen are the Oriental rat flea, Xenopsylla cheopis, and infected rodents. The path of transmission to humans usually involves a flea feeding on an infected rodent and becoming a carrier of infection. Once internalized, the bacteria will continue to reproduce until a large blockage is formed in the midgut of the flea, causing digestion and other gastrointestinal functions to cease. When the flea attempts to feed on humans, the blockage inhibits any blood from entering the stomach cavity; instead, portions of the blockage, often containing 11,000-24,000 bacilli, are regurgitated into the mammalian host. Virulence Factors Yersinia pestis encodes two antigenic molecules: Fraction 1 (F1) capsular antigen, and VW antigen. Both of these molecules are needed for pathogenicity, and are not expressed at temperatures lower than 37Â °C. This requirement is the main reason why Yersinia is not virulent in fleas, since their body temperature normally levels around 25Â °C. Yersinia is a model for studying Type III Secretion Systems (TTSS) that inject bacterial proteins into a host cell. In Y. pestis, it is the translocation of Yersinia outer proteins (Yop’s) that blocks the host cell’s ability to communicate with immune system cells and down-regulates the response of phagocytic host cells to infection.

Origin of Language Essay

Language is a means of communication that is made up of signs, symbols, and sounds or a combination of them. Signs represent something else like aroma and coffee, scent and flower, dark clouds and rain. Symbols are words we use to denote a thing or a being, such as man to mean person, dog to refer to an animal. Sounds are vocal emissions like laughter, sobbing, and groans suggestive of joy, sorrow, and pain. A more complex form of language is its organized system of semantics, syntax and phonetics. Spoken language is exclusive to humans. Language in whatever form continues to draw the interests of linguists, researchers, scientists and academicians, especially in the area of its origin. There are references in the Bible about language and communication. As early as the time of Adam and Eve, there was already some kind of communication and language between God and the both of them. In the temptation of Eve, the serpent communicated with her. There was only one language between Noah and his family. In the Tower of Babel, God was displeased with the people who refused to obey his command for them to spread out across the earth and so He gave them different languages. In the end they were forced to disperse to all corners of the world. This explains the why each geographic location have their own language. (Harub, 2003). Two contradicting theories on the origin of language are the Theory of Natural Selection and the Exaptation Theory. The Exaptation Theory simply put is when a body part is used for another purpose other than for which it was originally intended. An example of this theory is the feathers of a bird which is basically used to cover its body but later is made to glide and trap insects with. The brain processes from its cognitive structures were used by pre-historic ancestors to hunt and gather food. Language depends on cognitive processes and could have been possibly exapted in much the same way as the feathers. The Natural Selection Theory on the other hand provides that our language skills may have been from the brain structures that our ancestors may have possessed in their time. Brains have two neural pathways used for language and cognition. Humans use the ventral stream or pathway for linguistics. While both humans and non-humans, such as the chimps, possess the same neural makeup it is only the humans who have language. Cromm, 2003). Another theory of origin of language is the Theory of a Proto-Language. There are several stages in this theory: (1) the gesture-prior to-sound stage where body language is combined with sound. An example would be the index finger pressed on the lips with a hush sound, is a request to be quiet. (2) words-prior to-sentence stage where single words are connected with others to form a sentence and convey a thought or idea. I / have / three / red / apples are five separate words that connect to form a sentence and convey the thought about possessing three red fruits. 3) phrases-prior to-words stage is where a phrase with a single idea and each word is taken apart individually. An example is: a high and majestic mountain. Individual words are – high / majestic / mountain. The Proto-Language is original, distinct and has no precedent language. (AMNH, 2008). Different linguists each had their own theories. Jean Aitchison, author of â€Å"The Seeds of Speech† believed that physiologically, the human brain which had grown bigger in size than his primate ancestors’, made man capable of developing speech and language. John McCrone who supported the Evolution Theory of Language, was of the opinion that man was able to speak because they descended from the apes who themselves were able to speak when they found enough food to feed their enormous brains. Michael Corballis in his book â€Å"From Hand to Mouth: The Origin of Landscape† theorized that it was a gradual development for language, beginning with gesturing from the apes. With the bipedal hominids language evolved to a more complex body movement. Syntax and melodic sounds were the later developments with the emergence of the larger-brained homos. With the homo sapiens it was a combination of gestures and vocals, the gestures as enhancement and not as foundation. Carl Zimmer, another evolutionist, emphasized that the timeline of the origin and development of language can not be specifically traced because human skeletons leave very few significant clues. Many evolutionists maintain that languages today must have originated from only one ancient language characterized by different animal grunts and sounds. The development of language was a natural and not an intentional process. Noam Chromsky the eminent linguist from MIT, explained that different languages that we have now came from a common and universal language and that the human brains has a fixed and exclusive structure for language. (Harub, 2003). There are several other theories on the origin of language: Theory 1, it may have begun with the use of ordinary symbols to refer to significant objects. A scoop of earth refers to the land, a leaf to the tree, a drop of water to the rain. Theory 2, it may have originated from hand and body movements. One’s palm on one’s heart means me or I, pointing at whatever object means that object. Theory 3, it may have come from the imitation of the sounds of nature, like the splash of water, howling of the wind, the bark of the dog, Theory 4, it may have been from the emotive sounds of natural instinct and reaction, like grrr from anger, ahhh for satisfaction or comprehension, hmmm for agreement. Theory 6, it may have been because of the use of sounds to correspond to intended meanings, like long vowel sounds of o for moon and long e for creek, tree, sea. Theory 7, it may have originated from the grunts due to heavy loads, rhythmic monotones of work accompanied by gestures seeking assistance, like hand signals waving towards the one asking help as he makes the repetitive sounds of ugh ugh ugh. Theory 8, it may have been from words that were almost musical, uttered in cooing such as uhuhmm hmmm hummm hmmm, and laughter like hahahaha, hahahaaa. Theory 8, it came from sounds to advise or make known one’s presence as in yahooo, or to cry out for help as in heyyy. Theory 9, it originated from magical chants from religious rituals, similar to the Maori wish of good health (kia ora ra) and welcome (haere mai). Theory 10, it was an invention of some ancestors when they assigned certain sounds to mean certain things, beating of the drums to gather people. (Boeree, 2003). Michael C. Corballis made note of the stages of development of language. The earliest began over 6 million years ago with the apes and their simple body language as their means of communicating. This developed into a more complicated body gestures with the hominids. During this period sounds were used only in extreme cases as in highly emotional cries and distress calls. 5 million years back, a more sophisticated form of hand gestures by the early hominids were used. 2 million years ago, researches found an increase in the brain size of the homos believed to be the reason of the human’s higher development and facility in language. Vocals became permanent in communication and gestures were a good part of grammar. 100,000 years ago, speaking was in its fully developed stage that it became the main means of communication by homo sapiens. Gesturing was still in use but only as an embellishment. In the modern times with telecommunications technology verbal language become routine and common. It is interesting to note that in the advent of modern technology, with the shift from manual signals to spoken language, man is able to use his hands to work and his mind and vocals to communicate. (cited in Science Week, 2004). The search for the origin of language remains to be a continuing quest for scholars. Researches always lead to the theory of evolution. There is no way to know exactly when language began and where language came from. Scientific evidences such as fossils, DNA, comparative studies on animals and ancient languages can only provide clues but not enough traces. For a while, in 1866 the Society of Paris, the prominent academic language institute of the era, had given up in finding out more about language’s origin. It was taken as a retreat from the battle but not for long. To this day, forward thinkers such as the evolutionists are convinced that they must find convincing proof in the upcoming theories that should attempt to answer the query on the origin of language.

Predictive Sales Report Essay Example

Predictive Sales Report Essay Example Predictive Sales Report Essay Predictive Sales Report Essay There are some people that Just stop looking for employment; those individuals are not included in the unemployment rate. When there are people are in high volume looking for work and not working at all the retail stores will suffer with declining numbers based on less spending budgets, funds and capabilities. As the unemployment rate raises the retail stores will see more consumers willing ND able to spend. In 2009 the United States the sales for retail took a spike overall by 37%, (Rogers, 2009). In 2009 is when it took its major peak. Our projections and predictions show that the unemployment rate will stay at or around the 8% mark throughout 2013. This shows a consistency of this rate and can give retail stores a more balance on what to expect and business planning for the budgeted year. In 2011 article developers felt that putting up new centers as long as the unemployment rates where in the high single digits would not be good (Monkish, 2011). If developers do not want to put up new shops this can hinder growth of new tillers and also introduction of new vendors. This also serves as a plus for existing retailers who do not have to worry about competitors and can have all business located in one shop. References Bureau of labor statistics. (n. D. ). Retrieved from website: Balls. Gob/luau/ Monkish, E. (2011)