Urethral stenosis in children: treatment using urethroplasty with a vesical or oral mucosal graft

The fact that calcium ions regulate the secretion of thyroid hormones could be extended to explore how the mechanisms of anuran metamorphosis is controlled by thyroid hormones. In the present study, an attempt was made to investigate the effects of both calcium channel blocker, Diltiazem (DT) and calmodulin inhibitor, Trifluoperazine (TFP) on metamorphosis and various developmental stages of the anuran tadpole, Rana tigerina. Both DT (25 microM) and TFP (2 microM) treatments caused total inhibition of the development and metamorphosis of the tadpole at premetamorphic stages. The metamorphosis was delayed by DT and totally inhibited by TFP when tadpoles were exposed at prometamorphic stages. Both drugs could not affect the tadpoles at climax stage. The findings suggest an active involvement of thyroid hormone in premetamorphic tadpoles. Calcium channel blockage with DT could not prevent the progression of tadpoles through prometamorphic stages which suggest that the change in calcium pool is not a determining factor mediating thyroid hormone release mechanism. The study suggests that in tadpole growth thyroid hormone secretion is modulated by calmodulin bound intracellular calcium.     

Psychological distress in survivors of residential fires

This paper presents preliminary findings from an ongoing study of survivors of residential fires. The purpose of this study was to examine psychological distress and extent of loss in order to provide a psychological profile of survivors overtime. The sample (N = 69) was drawn consecutively from the database of residential fires available through the Philadelphia Fire Department. Levels of psychological distress were measured as well as reports of symptoms consistent with the diagnostic criteria for Post-traumatic Stress Disorder. The major findings indicate that residential fires caused significant and sustained distress. An agenda for further research and for services to survivors of these fires is presented.     

Use of the true absorption coefficient as a measure of bioavailability of radiocaesium in ruminants

Limitations of existing methods to describe the bioavailability of dietary radionuclides to ruminants (the transfer coefficient and apparent absorption coefficient) have led to the alternative suggestion of using the true absorption coefficient (A(t)). Various approaches to estimating A(t) for radiocaesium, involving the intravenous administration of a second isotope, are presented and discussed with reference to results from studies in which a range of radiocaesium sources were examined in sheep. Although estimates of A(t) differed between the sources, they were reasonably consistent between measurement techniques. Those methods which involved the estimation of endogenous faecal excretion of radiocaesium could be used with previously contaminated animals and did not require continuous administrations of radiocaesium isotopes, but gave unreliable results for sources of low bioavailability. Methods based on estimating the turnover rate of dietary radiocaesium through blood plasma were sufficiently sensitive to measure A(t) for the range of sources studied. However, they require previously uncontaminated animals and continuous administration of both isotopes for approximately 7 days. Bioavailability is more effectively measured as A(t) than as the transfer or apparent absorption coefficients since A(t) does not incorporate factors relating to the metabolism of radiocaesium in the tissues of the animal. The results of these studies show that differences in transfer coefficients between sheep and cattle and between sheep of differing ages are not due to variation in absorption across the gut. The potential for applying these approaches to other radioactive elements is discussed.     

Laparoscopic pelvic lymph node dissection for clinical staging of prostate cancer: encouraging preliminary results

OBJECTIVE: To evaluate the results of the first 72 laparoscopic pelvic lymph node dissections in patients with prostate cancer. DESIGN: Retrospective study of records. SETTING: Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital, Amsterdam, the Netherlands. METHOD: A retrospective study of records provided data on 72 patients with prostate cancer staged by laparoscopic lymph node dissection in the period 1993-1997. Per- and postoperative complications, operation time, number of removed lymph nodes, pathology result and duration of hospital stay were assessed. A comparison was made between the first series of 36 patients and the second series. RESULTS: In 9 patients the laparoscopic approach was converted to a laparotomy. This occurred six times in the first series of 36 patients and three times in the second series. The postoperative course was complicated six times in the first and four times in the second series. With increasing experience the mean operation time decreased from 140 min to 114 min in the second series (p < 0.0001). The mean number of nodes removed was equal in both series (7.5). Lymph node metastases were found in 20 patients (28%). Hospital stay was 2.9 days in the first series and 2.2 days in the second series (not significant). CONCLUSION: Laparoscopic pelvic lymph node dissection is a minimally invasive method for staging patients with prostate cancer. This staging procedure is of great benefit in patients scheduled for treatment with curative intent because of its accuracy and low morbidity. With increasing experience operation time, hospital stay and number of complications decrease.     

Concentration-dependent changes in the latency and amplitude of somatosensory-evoked potentials by desflurane, isoflurane and sevoflurane

Despite improvement in early diagnosis, surgical techniques, and general patient care, most deaths of cancer patients result from metastases. Recent studies have revealed that cytokines produced by cancer cells or by stromal cells play an important role into development the cancer metastasis. The formation of a cancer metastasis involves several major steps: 1) extensive vascularization; 2) local invasion; 3) adherence either to capillary endothelial cells or to subendothelial basement membrane; 4) extravasation; and 5) proliferation. In colon cancer, several cytokines such as growth factors, inflammatory cytokines, and angiogenic factors have been confirmed to be involved in each step of metastasis. This paper summarizes the involvement of cytokines in the development of invasion and metastasis in colon cancer.     

Comparison of Vitek GNI and GNI+ cards for identification of gram-negative bacteria

The GNI+ card has been developed by bioMerieux Vitek as an improvement over the GNI card for the identification of certain species of aerobic and facultative anaerobic bacteria. In this study, we tested 304 organisms from 30 different species on both the GNI and GNI+ cards. The GNI card correctly identified 285 (93.8%) of the isolates tested, and the GNI+ card correctly identified 287 (94.4%) of the isolates tested. The average time to reporting was 4.1 h for the GNI+ card compared to 5.7 h for the GNI card (P < 0.001). Overall, the GNI and GNI+ cards were comparable in identifying the organisms in this study while the GNI+ card gave substantially faster final test results.     

An in vitro approach for the study of dentinogenesis by organ culture of the dentine-pulp complex from rat incisor teeth

This article focuses on the experiences and role of a tutor while conducting a problem based learning (PBL) exercise to facilitate the learning of biochemistry and molecular biology. A case presentation of sickle cell anemia was used to frame a module. The objective of this experimental exercise was to assess the suitability and effectiveness of problem based learning in the first year of undergraduate medical course and to practice self-assessment by tutors in this new role of a facilitator of learning through small group discussion. A tutor during such a learning session encouraged the students to apply their reasoning to analyze the problem and to develop self-directed learning skills in acquiring the knowledge appropriate to their perceived needs to work on a problem. The tutors ensured that they apply this knowledge in their work with other similar problems that they would encounter later in life.     

Role of nitric oxide and platelet-activating factor in the initiation of indomethacin-provoked intestinal inflammation in rats

Some C-type lectins possess phospholipid-binding ability, which may be of physiological importance. Human mannan-binding lectin (MBL) was found to bind specifically to solid-phase phosphatidylserine (PS), phosphatidylinositol (PI) and phosphatidylcholine (PC), but not cardiolipin (CL), in a concentration-dependent manner. This property was inhibited by EDTA and by monosaccharides, and exhibited a similar pH dependence to the carbohydrate (mannan)-binding activity of MBL. These findings may be of immunological relevance.     

Prevention of vertical HIV transmission with zidovudine: projected impact of HIV testing and prenatal care

We sought to estimate the impact of maternal HIV testing and prenatal care on the potential to reduce vertical transmission through zidovudine (AZT) use by HIV-infected mothers. We evaluated the prepartum maternal HIV diagnosis rate, prenatal care, disease stage, and vertical transmission rate (from a two-part mixture model) using New York State Medicaid and vital statistics data for HIV-infected mothers and their singletons in 1985-90. We used published data to estimate the effect of AZT on vertical transmission and expert input to define other parameters for the model. Our HIV-infected (N = 1514) had a vertical transmission rate of 27.0%. HIV was diagnosed prepartum for 39.5% of women in 1990. Transmission would have been 22.2% if AZT had been taken only by the subset of women diagnosed prepartum with HIV and receiving prenatal care by 34 weeks gestation (86.7%). Transmission would have dropped to 11.2% if all women had been diagnosed prepartum with HIV and received adequate prenatal care. The observed deficiencies in prenatal care and maternal HIV diagnosis rates in this Medicaid population-based cohort must be addressed to realize the promise of AZT to reduce vertical transmission.