ANTIDEPRESSANT THERAPY AND BEHAVIOURAL COMPETENCE

SUMMARY Major depression can impair an individual's motivation to perform routine daily activities and cause a deterioration in cognitive and psychomotor function. Some antidepressants add to pathological dysfunction through unwanted side-effects. Although most patients eventually recover as a simultaneous consequence of tolerance and therapeutic response, some may not. Where side-effects continue to retard normal recovery they can be called behaviourally toxic, which can be classified as disruptive, inhibitory or provocative. Disruptive behavioural toxic effects are measured using either psychometric tests or simulations of real-life activities (for example, a driving test). There are no widely-accepted tests for inhibitory or provocative behavioural toxicity, and assessments of antidepressants are made on the basis of case studies. This review summarises the results of psychometric and real-life simulation tests and compares the effects of antidepressants on behaviour competence. The purpose is to identify those drugs that seem to be the most and least likely to produce behavioural toxicity.     

Intraoperative bone scintigraphy in orthopaedic surgery

A sterilisable radiation probe of small dimensions was designed to locate the lesions at orthopaedic surgical sites according to the procedure of intraoperative bone scintigraphy. The probe has a collimated opening 2 mm in diameter. It is connected to a portable radioactivity counter which converts the disintegration rates detected at surgical sites into an acoustic signal that increases steeply with increasing disintegration rate. The acoustic signal enables the surgeons and isotope specialists to readily monitor radioactivity in the region of interest without attention being distracted from the surgical site. Dimethylaminodiphosphonate (designated SF44) was the osteotropic radiopharmaceutical chosen for carrying out intraoperative bone scintigraphy, since the available data show that this chemical increases the pathological: normal bone uptake ratio of the lesion by 25% compared to the usual diphosphonates. Forty-seven orthopaedic interventions were carried out according to the intraoperative bone scintigraphy procedure. They showed that this procedure facilitated the rapid location of the lesion, the objective termination of the operation, less frequently the reduction in dimension of the excised areas, and rarely the simplification of the surgical technique. Practice of intraoperative bone scintigraphy requires proper training and caution.     

Review of the Lynch syndrome: history, molecular genetics, screening, differential diagnosis, and medicolegal ramifications

Platelets have a central role in the development of arterial thrombosis and subsequent cardiovascular events. An appreciation of this complex process has made antiplatelet therapy the cornerstone of cardiovascular disease management. However, numerous patients will experience a recurrent atherothrombotic vascular event despite adequate antiplatelet therapy. Individual differences in the rate of platelet activation and reactivity markedly influence normal hemostasis and the pathological outcome of thrombosis. Such an individual variability is largely determined by environmental and genetic factors. These are known to either hamper platelets' response to agonists, and thereby mimic the pharmacological modulation of platelet function or mask therapy effect and sensitize platelets. In this article, we reviewed the antiplatelet mechanisms of aspirin and clopidogrel and the possible role of different polymorphisms, which may affect the efficacy of antiplatelet therapy. Heterogeneity in the way patients respond to aspirin and clopidogrel may in part reflect variation in cyclooxygenase (COX)-1, COX-2, glycoprotein (GP) Ib alpha, GP Ia/IIa, GP IIb/IIIa, UGT1A6*2, P2Y₁, P2Y₁₂, CYP2C9, CYP3A4 and CYP3A5 genotypes.     

Clinical features of chromosome 22q11.2 microdeletion syndrome in 208 Chilean patients

Patients with chromosome 22q11 deletion syndrome exhibit significant phenotypic variability. Epidemiologic data suggest a higher incidence in Hispanics, but limited clinical information is available from Latin-American patients. We describe the clinical features of Chilean patients with 22q11 deletion syndrome and compare their findings with those reported in large European, Japanese and US series. Data were obtained from 208 patients from five medical centers. Mean age at diagnosis was 5.2 years, with a median of 2.3 years. Congenital heart defects were present in 59.6%, lower than other large series that averaged 75.8%. Palate abnormalities were present in 79%, higher than previous reports averaging 56%. Patients with congenital heart disease were diagnosed earlier (median 0.3 years of age) than those without heart defects (median 5.6 years) and had greater mortality attributable to the syndrome (9.8% vs 2.4%, respectively). The differences in frequencies of major anomalies may be due to growing awareness of more subtle manifestations of the syndrome, differences in clinical ascertainment or the presence of modifier factors. These observations provide additional data useful for patient counseling and for the proposal of health care guidelines.     

Previous exposure to hormone replacement therapy and confounders in metabolic studies.

OBJECTIVE: The quantity of intra-abdominal fat is highly associated with the development of diabetes mellitus. We sought to determine whether recent hormone replacement therapy (HRT) use modifies central fat and insulin sensitivity in postmenopausal women compared with women who had never used HRT. DESIGN: We measured intra-abdominal fat, subcutaneous abdominal fat, and sagittal diameter at the L4-L5 vertebral disc space using computed tomography imaging. Total body fat and fat-free mass were measured using dual energy x-ray absorptiometry. Insulin sensitivity was assessed using the euglycemic hyperinsulinemic clamp technique in 42 nonobese postmenopausal women, age 51 +/- 4 years (12 recent HRT users plus 30 never-users). All women who were taking HRT discontinued it for 2 months before the study. RESULTS: After statistical adjustment for age, previous use of HRT was associated with decreased intra-abdominal fat (72 +/- 34 cm2) compared with no HRT use (96 +/- 33 cm2; p = 0.05). This difference remained significant after adjustment for time since menopause. When previous HRT users were compared with nonusers, there were no differences in subcutaneous abdominal fat, sagittal diameter, fat-free mass, total fat, insulin sensitivity, or body weight. CONCLUSIONS: Recent HRT use is associated with lower intra-abdominal fat in nonobese, early postmenopausal women. This finding suggests a carry-over effect of HRT on intra-abdominal fat. Recent HRT use does not seem to be associated with differences in glucose disposal.     

Diaphragm of the gallbladder: a case report.

Gallbladder anomalies are rare and normally affect its shape, size, and position. We report on a 3-year-old boy with a gallbladder divided transversally by a windsock-type diaphragm, isolating the fundus from the rest of the biliary tree. Bilobed and multiseptated gallbladder have been described before, but this is the first isolated case of a congenital hourglass gallbladder.