Adulterant profile of illicit street heroin and reduction of its precipitated physical dependence withdrawal syndrome by extracts of St John's wort (Hypericum perforatum)

The study evaluated the adulterants in a specimen of illicit street heroin supplied under strict control by the Pakistan Anti‐Narcotic Force. It also examined the effects of Hypericum perforatum L. extracts on the naloxone‐induced heroin withdrawal syndrome. The GC‐MS analysis of the specimen showed that in addition to heroin (37.8%), the sample also contained caffeine (8.4%), phenobarbitone (12.7%), 6‐acetyl codeine (5.3%), 6‐acetyl morphine (10.9%) and noscapine (15.8%). Administration of the heroin to rats for 8 days induced physical withdrawal signs of abdominal constriction, diarrhoea and vocalization on touch after naloxone treatment. Aqueous Hypericum perforatum extracts (20 mg/kg twice daily chronically or as a single acute dose 90 min before naloxone) given orally to the heroin dependent rats attenuated abdominal constrictions both acutely and chronically while the hydroethanol and ethanol extracts were only effective in acutely treated animals. Diarrhoea was ameliorated by the hydroethanol and ethanol extracts following acute or chronic heroin treatment while the aqueous extract failed to show any effect. Vocalization on touch during withdrawal was reduced by all the extracts either chronically or acutely with the exception of chronic treatment with hydroethanol extracts. The findings suggest that Hypericum perforatum is capable of reducing the physical signs of opiate withdrawal. Copyright © 2008 John Wiley & Sons, Ltd.     

Anticonvulsant activities of nutmeg oil of Myristica fragrans

The purpose of this study was to investigate the anticonvulsant activity of the volatile oil of nutmeg, the dried seed kernel of Myristica fragrans Houtt, using well‐established animal seizure models and to evaluate its potential for acute toxicity and acute neurotoxicity. The volatile oil of nutmeg (nutmeg oil) was tested for its effects in maximal electroshock, subcutaneous pentylenetetrazole, strychnine and bicuculline seizure tests. All the experiments were performed at the time of peak effect of nutmeg oil. Nutmeg oil showed a rapid onset of action and short duration of anticonvulsant effect. It was found to possess significant anticonvulsant activity against electroshock‐induced hind limb tonic extension. It exhibited dose dependent anticonvulsant activity against pentylenetetrazole‐induced tonic seizures. It delayed the onset of hind limb tonic extensor jerks induced by strychnine. It was anticonvulsant at lower doses, whereas weak proconvulsant at a higher dose against pentylenetetrazole and bicuculline induced clonic seizures. Nutmeg oil was found to possess wide therapeutic margin, as it did not induce motor impairment when tested up to 600 µL/kg in the inverted screen acute neurotoxicity test. Furthermore, the LD₅₀ (2150 µL/kg) value was much higher than its anticonvulsant doses (50–300 µL/kg). The results indicate that nutmeg oil may be effective against grand mal and partial seizures, as it prevents seizure spread in a set of established animal models. Slight potentiation of clonic seizure activity limits its use for the treatment of myoclonic and absence seizures. Copyright © 2008 John Wiley & Sons, Ltd.     

Peer assessment in the objective structured clinical examination: A scoping review

Background: The objective structured clinical examination (OSCE), originally designed with experts assessing trainees’ competence, is more frequently employed with an element of peer assessment and feedback. Although peer assessment in higher education has been studied, its role in OSCEs has not reviewed.

Aims: The aim of this study is to conduct a scoping review and explore the role of peer assessment and feedback in the OSCE.

Methods: Electronic database and hand searching yielded 507 articles. Twenty-one full records were screened, of which 13 were included in the review. Two independent reviewers completed each step of the review.

Results: Peer-based OSCEs are used to assess students’ accuracy in assessing OSCE performance and to promote learning. Peer examiners (PE) tend to award better global ratings and variable checklist ratings compared to faculty and provide high-quality feedback. Participating in these OSCEs is perceived as beneficial for learning.

Conclusions: Peer assessment and feedback can be used to gauge PE reliability and promote learning. Teachers using these OSCEs must use methodology which fits their purpose. Competency-based education calls for diversification of assessment practices and asks how assessment impacts learning; the peer-based OSCE responds to these demands and will become an important practice in health professions education.     

Comparative antigenic analysis of Mycobacterium avium complex (MAC) isolates from AIDS patients.

Sonicates of several Mycobacterium avium complex (MAC) strains isolated from acquired immunodeficiency syndrome (AIDS) patients were characterized in order to study the prominent antigens of these strains. Sonicates of 6-week-old cultures were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. A major 12 kDa glycoprotein antigen was observed in all the sonicates along with other proteins ranging up to 100 kDa. Western blotting, using the 12 kDa M. leprae 'specific' murine monoclonal antibody (MAb) MLO6, indicated the presence of a determinant in the 12 kDa antigen (in all the MAC isolates studied) which was immunologically cross-reactive with the 12 kDa antigen of M. leprae. The transparent variant of MAC 101 also demonstrated MLO6 reactivity while the opaque variant did not. Polyclonal antiserum raised against MAC 101 sonicate reacted with all the MAC isolates in immunodiffusion. These observations point to the cross-reactivity between these strains and suggest that they possess a M. leprae 'specific' determinant on a cross-reacting component which could be involved in virulence.     

The effects of unilateral and multifocal lesions on the WAIS-R: a factor analytic study of stroke patients.

An exploratory maximum likelihood factor analysis of the inter-correlations among the 11 subtests of the WAIS-R was undertaken for 167 patients who had a primary diagnoses of cerebrovascular accident (right hemisphere, n = 79; left hemisphere, n = 55; diffuse or multifocal, n = 33). On the WAIS-R, this sample performed below normative standards (average scaled score = 7.1), but demonstrated a pattern of variability among subtests similar to the normative groups. Interestingly, VIQ-PIQ discrepancy analyses revealed V > P profiles for patients with lesions in either or both hemispheres. The best fit for the WAIS-R matrix was an oblique two-factor model comprised of the Verbal and Performance subtests. This factor solution, which was moderately correlated (.52), accounted for 58.8% of the total variance. The stability of a two-factor structure in this neurologic impaired population suggests that the WAIS-R is a robust measure, even when used within such a rehabilitation population. Only two of the eleven subtests (i.e., Comprehension and Picture Arrangement), however, were related to lesion site. Rehabilitation settings may need to rely more on neuropsychological procedures that measure the more "fluid" areas of neurocognitive ability, in contrast to the WAIS-R which appears less sensitive to the neurological impairment associated with stroke.     

AVASCULAR NECROSIS: A RARE COMPLICATION OF STEROID THERAPY FOR PEMPHIGUS

A patient of pemphigus vulgaris presented with avascular necrosis of the femur after long-term high-dose corticosteroid therapy. Corticosteroids used on a long-term basis can cause avascular necrosis of bone and this has been seen in various diseases. This is attributable to both the disease process itself and the therapy i.e. corticosteroid usage. In dermatological practice avascular necrosis of bone has been seen more commonly with SLE and also with psoriasis using long-term steroids. Avascular necrosis in a case of pemphigus on steroid therapy is a rare finding. We report such a case of pemphigus vulgaris developing avascular necrosis of bone following corticosteroid therapy.     

Establishing a baseline phase behavior in magnetic resonance imaging to determine normal vs. abnormal iron content in the brain

PURPOSE: To establish a baseline of phase differences between tissues in a number of regions of the human brain as a means of detecting iron abnormalities using magnetic resonance imaging (MRI). MATERIALS AND METHODS: A fully flow-compensated, three-dimensional (3D), high-resolution, gradient-echo (GRE) susceptibility-weighted imaging (SWI) sequence was used to collect magnitude and phase data at 1.5 T. The phase images were high-pass-filtered and processed region by region with hand-drawn areas. The regions evaluated included the motor cortex (MC), putamen (PUT), globus pallidus (GP), caudate nucleus (CN), substantia nigra (SN), and red nucleus (RN). A total of 75 subjects, ranging in age from 55 to 89 years, were analyzed. RESULTS: The phase was found to have a Gaussian-like distribution with a standard deviation (SD) of 0.046 radians on a pixel-by-pixel basis. Most regions of interest (ROIs) contained at least 100 pixels, giving a standard error of the mean (SEM) of 0.0046 radians or less. In the MC, phase differences were found to be roughly 0.273 radians between CSF and gray matter (GM), and 0.083 radians between CSF and white matter (WM). The difference between CSF and the GP was 0.201 radians, and between CSF and the CN (head) it was 0.213 radians. For CSF and the PUT (the lower outer part) the difference was 0.449 radians, and between CSF and the RN (third slice vascularized region) it was 0.353 radians. Finally, the phase difference between CSF and SN was 0.345 radians. CONCLUSION: The Gaussian-like distributions in phase make it possible to predict deviations from normal phase behavior for tissues in the brain. Using phase as an iron marker may be useful for studying absorption of iron in diseases such as Parkinson's, Huntington's, neurodegeneration with brain iron accumulation (NBIA), Alzheimer's, and multiple sclerosis (MS), and other iron-related diseases. The phases quoted here will serve as a baseline for future studies that look for changes in iron content.     

Drug-prescribing patterns during pregnancy in the tertiary care hospitals of Pakistan: a cross sectional study

Background

Low birth weight (LBW) is considered as a major multifaceted public health concern. Seventy-two percent of LBW infants are born in Asia. An estimation of 8% LBW infants has been reported for Eastern Mediterranean region including Iran. This study investigated contributory factors of LBW in singleton term births in Tehran, Iran. Tehran is a multicultural metropolitan area and a sample from the general population in Tehran could be regarded as a representative sample of urban population in Iran.

Methods

This was a retrospective study using data from 15 university maternity hospitals in Tehran, Iran. Data on all singleton term births in these hospitals were extracted from case records during a one calendar year. Study variables included: maternal age, maternal educational level, history of LBW deliveries, history of preterm labor, cigarette smoking during pregnancy, number of parities, chronic diseases and residential area (Tehran versus suburbs of Tehran). In order to examine the relationship between LBW and demographic and reproductive variables the adjusted logistic regression analysis was performed.

Results

In all, data for 3734 term pregnancies were extracted. The mean age of women was 25.7 (SD = 5.3) years and 5.2% of term births were LBW. In addition to association between LBW and maternal age, significant risk factors for LBW were: history of LBW deliveries [adjusted odds ratio (OR) = 2.53, 95% confidence interval (CI) = 1.06–6.03], smoking during pregnancy (OR = 4.64, 95% CI = 1.97–10.95) and chronic diseases (OR for hypertension = 3.70, 95% CI = 2.25–6.06, OR for others = 2.04, 95% CI = 1.09–3.83).

Conclusion

The findings indicate that in addition to maternal age, history of LBW deliveries; smoking during pregnancy and chronic diseases are significant determinants of LBW in this population. This is consistent with national and international findings indicating that maternal variables and risk behaviors during pregnancy play important roles on LBW.