Treatment of rats during pubertal development with 2,3,7,8-tetrachlorodibenzo-p-dioxin alters both signaling kinase activities and epidermal growth factor receptor binding in the testis and the motility and acrosomal reaction of sperm

Different doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) (0.1, 1, 5, and 10 micrograms/kg body wt) were administered i.p. to 21-day-old male Sprague-Dawley rats. Control animals received the same volume of the vehicle (acetone:corn oil, 1:19). Body weight and daily food intake were recorded during the 90-day time course of the study. Random samples of five rats were sacrificed at 34, 49, 62, and 90 days of age. Epidermal growth factor receptor (EGFR) in whole testis was measured, as were the activities of c-Src kinase, protein tyrosine kinase (PTK), mitogen-activated protein 2 kinase (MAP2K also termed as Erk2), protein kinase A (PKA), and protein kinase C (PKC). Testicular tissue from 90-day-old rats was evaluated for histopathology, and sperm numbers in whole testis were counted to estimate daily sperm production. The motility of sperm in the vas deferens and caudal segments of the epididymis of 90-day-old rats was measured by computer assisted sperm analysis (CASA) and the function of the sperm was tested by assessment of acrosome reactions. A dose of 10 micrograms/kg resulted in testicular atrophy and histopathologic examination revealed a decrease in the diameter of the seminiferous tubules. Sertoli cell nuclei were clearly seen, but the spermatogonial population was totally absent. Lower doses of TCDD did not affect testicular histology, but doses as low as 1 microgram/kg significantly decreased testicular sperm numbers and affected some sperm functions (motility parameters and acrosome reactions) in 90-day-old rats. Significant decreases in EGFR were found in 34-day-old rats and this effect on EGFR was sustained until the end of the experiment (90 days). Although TCDD significantly increased c-Src kinase activity in immature and mature rats, opposite effects of TCDD on activities of PTK, PKA, and PKC were found in 34-day-old rats vs 49-, 62-, and 90-day-old rats. When 10 micrograms TCDD/kg was administered to 21-day-old rat, 24-h after c-Src kinase inhibitor geldanamycin, there was no testicular atrophy and no change in the daily sperm production was found. These findings provide evidence for involvement of Src kinase signaling and EGFR in the mechanism by which TCDD disrupts testicular development and subsequently affects testis function.

[Epidemiology of tuberculosis in Poland and in the world]

The paper describes the risk of tuberculosis infection and the incidence of the disease as measures of the epidemiological situation and presents data on the epidemiological situation of tuberculosis in Poland and the world. It also describes the effectiveness of the national tuberculosis control programme in Poland. The annual risk of tuberculosis infection in Poland is estimated at 0.2% which is about 10 times higher than the lowest one in Europe (the Netherland), but there are countries in the world with the risk of 2.0% and higher. The incidence of tuberculosis in Poland (all forms) declined from 182.6/100,000 in 1965 to less than 40,0/100,000 in 1996, of which less than half were bacteriologically positive cases. The incidence of smear positive cases, the most infectious group, declined from 18.7/100,000 in 1980 to 9.7/100,000 in 1995. All cases of tuberculosis in Poland are treated with 4-drugs regimen in the intensive phase of treatment and 3-drugs in the continuation phase. The duration of treatment is 6-8 months and the cure rate is above 90%.

Normal triglyceride levels and coronary artery disease events: the Baltimore Coronary Observational Long-Term Study

OBJECTIVES

This study sought to evaluate long-term predictors of coronary events in men and women with arteriographically defined coronary artery disease (CAD).

BACKGROUND

There is conflicting evidence of the role of triglycerides (TGs) as a prognosticator of CAD, and no studies have examined the long-term outcome of "normal" levels in predicting new coronary events.

METHODS

This was a retrospective cohort study that evaluated 740 consecutive patients presenting for diagnostic coronary arteriography between 1977 and 1978. Beginning in 1988, patients with arteriographic CAD (n=350) were recontacted and asked to complete detailed medical questionnaires. Case and control patients were stratified by development of new coronary events, including death from ischemic heart disease, nonfatal myocardial infarction and revascularization.

RESULTS

There were 199 events during the 18-year follow-up period. The mean high density lipoprotein cholesterol (HDL-C) was significantly lower (35 vs. 39 mg/dl; p=0.002) and TGs higher (160 vs. 137 mg/dl; p=0.03) in case patients than in control patients; After adjusting for age, gender and beta-adrenergic blocking agent use, multiple logistic regression analysis revealed the following independent predictors of CAD events: diabetes mellitus (relative risk [RR] 2.1, 95% confidence interval [CI] 1.4% to 3.1%), HDL-C <35 mg/dl (RR 1.5, 95% CI 1.1% to 2.00) and TGs >100 mg/dl (RR 1.5, 95% CI 1.1% to 2.1%). A Kaplan-Meier analysis revealed significantly reduced survival from CAD events in patients with baseline TG levels > or = 100 mg/dl compared with TG levels <100 mg/dl (p=0.008).

CONCLUSIONS

TG levels previously considered "normal" are predictive of new CAD events. The cutpoints established by the National Cholesterol Education Program for elevated TGs (>200 mg/dl) may need to be refined.

Economic analysis of fluconazole versus amphotericin B for the treatment of candidemia in non-neutropenic patients

Fluconazole (FLU) is an alternative to amphotericin B (AMB) for the treatment of candidemia in non-neutropenic patients. This agent has similar clinical efficacy but significantly reduced adverse effects compared with AMB. Using the database from a Canadian randomised multicentre comparative trial of FLU versus AMB in the treatment of non-neutropenic patients with candidemia, an economic analysis of antifungal therapy was conducted from a Canadian hospital perspective. Patient records were examined for information containing hospital resource consumption. This included the costs for primary intravenous therapy with either AMB or FLU, laboratory tests, patient clinical monitoring and adverse effects management. The robustness of the baseline results were then tested by a comprehensive sensitivity analysis. The mean duration of therapy in the AMB and FLU arms was 17.1 and 23.7 days, respectively (p < 0.001). Assuming that all of the FLU was administered intravenously, the outcomes of the baseline economic analysis revealed that the treatment cost for patients randomized to receive FLU was approximately 50% higher than that for patients treated with AMB [AMB: $Can2370 vs FLU: $Can3578; p = 0.001 ($Can = Canadian dollars)]. In the sensitivity analysis, substitution to oral FLU after 7 days of intravenous therapy produced economic differences that were no longer statistically significant (AMB: $Can2370 vs FLU: $Can2705; p = 0.10). These results suggest that the FLU administration regimen used in the Canadian randomized trial for the treatment of candidemia in non-neutropenic patients may result in increased hospital costs compared with AMB. However, comparable expenditures could be realized if FLU is administered intravenously for the first 7 days and then orally in patients whose condition allows for reliable oral therapy.

How do I diagnose and treat wound infection?

This article is the first in a ‘How do I?’ series, which will examine various aspects of wound management. With best practice continuously the goal, these articles will explore options and provide the nurse with practical advice on how to tackle the issues in question. The first article in the series aims to answer the question: ‘How do I diagnose and treat wound infection?’

Menaquinone-7 in the reaction center complex of the green sulfur bacterium Chlorobium vibrioforme functions as the electron acceptor A1

Photosynthetically active reaction center complexes were prepared from the green sulfur bacterium Chlorobium vibrioforme NCIMB 8327, and the content of quinones was determined by extraction and high-performance liquid chromatography. The analysis showed a stoichiometry of 1.7 molecules of menaquinone-7/reaction center. No other quinones were detected in the isolated reaction centers, whereas membrane preparations also contained chlorobiumquinone. The possible involvement of quinones in electron transport was investigated by electron paramagnetic resonance (EPR) spectroscopy. A highly anisotropic radical was detected by Q-band EPR spectroscopy in both membranes and isolated reaction centers following dark reduction with sodium dithionite and photoaccumulation at 205 K. At 34 GHz, the EPR spectrum is characterized by a g tensor with gxx = 2.0063, gyy = 2.0052, gzz = 2.0020 and delta B of 0.7 mT, consistent with its identification as a quinone. This spectrum is highly similar in terms of g values and line widths to photoaccumulated A1- in photosystem I of Synechococcus sp. PCC 7002. The results indicate that menaquinone-7 in the green sulfur bacterial reaction center is analogous to phylloquinone in photosystem I.

[Reasons for chronic expectoration in patients with pulmonary tuberculosis registered in the Central Tuberculosis Registry]

The aim of the retrospective population-based study was to identify reasons for failure of sputum culture negativity from the 12th month on since the start of chemotherapy of pulmonary tuberculosis (PTB). Medical records of 97 patients with PTB (85 men and 12 women) remaining sputum culture positive for over 12 months, reported to the Central TB Registry (1988-1990), were reviewed. The mean age was 46.7 years. There were 39.2% blue collar workers, 18.6% peasants, 21.6% unemployed, 14.4% pensioners. Only 4.1% constituted persons with education above elementary level. 44 patients abused alcohol, 13 of them had severe alcohol related health problems. Initial susceptibility tests were done in 79 subjects, showing resistance to at least one drug in 15. In 21 subjects the new resistance occurred during observation. The mean period until conversion of sputum culture was 23.5 months. Sputum culture conversion was finally achieved in 63 (64.9%) subjects. The reasons for delayed sputum culture conversion were identified in 86 persons. The main reason for long duration of positive sputum culture in 75 (87.2%) subjects was poor compliance. In 7 (8.1%) cases evident treatment error was relevant. Serious adverse reactions to drugs were responsible in 4 (4.6%).

Diet and psychological health: a case study

This article presents an example of the case study as a valuable methodological option for researching alternative and complementary therapies. This case study investigated the experiences of an individual in recovery from substance abuse who reported improvements in psychological symptoms following dietary changes. The underlying premise explored was that dietary or nutritional components can have a significant effect on psychological health and should therefore be used with other biopsychosocial approaches for the prevention and treatment of mental disorders. Until there is a shift in research priorities to encourage medical-cultural recognition of the impact of diet on psychological and physical health, smaller studies that rigorously investigate case reports can provide useful information to practitioners as well as laypeople.

Learning with technology: use of case-based physical and computer simulations in professional education

This presentation will clarify contemporary ideas on the role of technology in education and how it can be employed to improve student learning experiences and outcomes. The paper will emphasise RMIT's role in providing quality education that is relevant to today's world and professional practice. It will examine a specific collaborative (RMIT & ACU), interdisciplinary project 'Pregnancy Simulator: Developing and Enhancing Student Learning of Assessment Skills'. This project consist of a physical pregnancy model connected to a multi-media computer-assisted learning package for the purpose of enhancing student learning of abdominal assessment skills. Our paper outlines an innovative technology-based teaching project and includes current educational issues or problems encountered in professional education, steps already taken to address these difficulties and how this project intends to facilitate learning. It identifies expected learning outcomes for midwives, nurses and medical students, and examines pedagogical principles applied to technological applications designed to provide guided discovery for allowing students to build confidence and competence in professional education. The case-based physical and computer simulations contextualise learning to assist transfer of learning to real world situations. This paper will also discuss how technology-based projects can be evaluated and integrated into university curricula to enhance student learning.

Hematomas and limb skeletal malformations in chicken embryos following exposure to 5-fluoro-2-deoxyuridine

Vascular injury or interruption may play a role in vertebrate limb teratogenesis. Since 5-fluoro-2'-deoxyuridine (FdU) can cause vascular injury in the murine limb and skull prior to the appearance of skeletal malformations in these structures, we studied the effects of this chemical on skeletal development in the chick embryo and noted any vascular injury. The yolk sacs of day three chick embryos (Hamburger and Hamilton states 17-19) were injected with solutions of vary concentrations of FdU in saline. The embryos developed until the 10th day of incubation when they were fixed for study. Uninjected, saline injected, and sham injected control embryos were similarly fixed. Upon gross inspection, frequent diffuse and saccular hematomas, as well as fluid-filled blisters, were noted in the limbs of embryos treated with FdU. After the embryos were fixed and cleared, and the skeletons stained, significant skeletal malformations were observed in these limbs. Bony elements of both the upper and lower limbs were affected in at least some of the embryos. The combination of FdU-induced hematomas and blisters with associated skeletal malformations in the same regions of some embryos suggests a relationship between these phenomena.

Linkage of the apo CIII microsatellite with isolated low high-density lipoprotein cholesterol

To evaluate whether a highly polymorphic microsatellite region within intron 3 of the apolipoprotein (apo) CIII gene is linked to the isolated low HDL-C phenotype, we studied eight unrelated probands (mean HDL-C = 10+/-5 mg/dl) and 157 biological family members. After PCR amplification of genomic DNA and denaturing polyacrylamide gel electrophoresis, 26 alleles were identified in this microsatellite including 9 alleles heretofore unreported. Quantitative sib-pair linkage analysis demonstrated strong evidence of linkage between the isolated low HDL-C phenotype and the apo CIII microsatellite region (P = 0.007). The microsatellite was also linked to apo AI (P = 0.001), the primary apolipoprotein of HDL-C. Therefore, this highly polymorphic microsatellite region is a potentially important marker in the genetic evaluation of the isolated low HDL-C phenotype.

The case study as a scientific method for researching alternative therapies

This article argues that the case study design is a research method capable of providing valuable data and insight into alternative therapies. The background and roots of the case study in medicine and clinical practice are covered, and the status of the case study as a scientific method is examined. The highly regarded randomized controlled clinical trial--though often powerful and useful--is neither feasible nor ideal for understanding the effects of many unconventional treatment approaches. Given the complexity of the factors involved in unconventional therapeutic applications--health beliefs, changing health paradigms, patient/practitioner interactions, multiple treatment modalities, multiple symptom profiles--the case study approach offers an alternative methodological route for investigating and generating findings in this arena. Reliability and validity of data collection, data reduction, and interpretation can be enhanced through steps discussed in this article. As it continues to work with evidence that is currently unorganized, the field of alternative medicine can benefit both in clinical prowess and scientific stature from additional, carefully conducted case studies.

An NCEP II diet reduces postprandial triacylglycerol in normocholesterolemic adults

We compared the fasting and postprandial response to a National Cholesterol Education Program (NCEP) II diet with that of a diet high in total (40% of energy) and saturated fat. In free-living conditions, 17 healthy normolipidemic, normoglycemic men and women consumed a high-fat diet, a maintenance diet and the NCEP II diet, for 1 mo each. At the completion of each dietary period, an oral fat load (70 g/m2 body surface area) was administered and plasma triacylglycerol (TAG) determined every 2 h for 8 h. Compared with the high-fat phase, the NCEP II diet was associated with significantly lower energy intake (12.1 +/- 1.1 vs. 7 +/- 0.7 MJ/d) and final body weight (78 +/- 3.8 vs. 76.3 +/- 3.5 kg) (P < 0.01). Plasma high density lipoprotein cholesterol, apolipoprotein (apo) A-I and ApoB concentrations were also significantly lower when subjects consumed the NCEP II diet rather than the high-fat diet (P </= 0.004). There were no significant differences in subjects fasting TAG, glucose or insulin concentration between the high fat and NCEP II diet periods. However, the postprandial plasma TAG response to the fat load was lower after completing the NCEP II than after the high-fat diet period (P = 0.045). Under free-living conditions, a NCEP II diet was associated with weight loss and a decrease in postprandial but not fasting TAG. Because dietary alteration may not affect fasting TAG levels, thorough assessment of a dietary intervention should include measurements of postprandial TAG.

The use of fluorogenic substrates to measure fungal presence and activity in soil

Our objective was to determine if 4-methylumbelliferyl-labelled enzyme substrates could be used to detect and quantify specific components of chitinase and cellulase activities as specific indicators of the presence and activity of fungal biomass. The fluorogenic substrates 4-methylumbelliferyl (MUF) N-acetyl-beta-D-glucosaminide and MUF beta-D-lactoside were used for the detection and quantification of beta-N-acetylglucosaminidase (EC 3.2.1.30) (NAGase) and endo 1,4-beta-glucanase (EC 3.2.1.4)/cellobiohydrolase (EC 3.2.1.91) (CELase), respectively. Culture screenings on solid media showed a widespread ability to produce NAGase among a taxonomically diverse selection of fungi on media with and without added chitin. NAGase activity was expressed only in a limited number of bacteria and on media supplemented with chitin. The CELase activity was observed only in a limited number of fungi and bacteria. Bacterial CELase activity was expressed on agar media containing a cellulose-derived substrate. In soil samples, NAGase activity was significantly correlated with estimates of fungal biomass, based on the content of two fungus-specific indicator molecules, 18:2 omega 6 phospholipid fatty acid (PLFA) and ergosterol. CELase activity was significantly correlated with the PLFA-based estimate of fungal biomass in the soil, but no correlation was found with ergosterol-based estimates of fungal biomass.

Determinants of rifabutin-associated uveitis in patients treated with rifabutin, clarithromycin, and ethambutol for Mycobacterium avium complex bacteremia: a multivariate analysis. Canadian HIV Trials Network Protocol 010 Study Group

Uveitis occurred in a substantial proportion of AIDS patients receiving rifabutin, 600 mg daily, together with clarithromycin and ethambutol for treatment of Mycobacterium avium complex bacteremia. A case-control study was undertaken to examine potential risk factors for developing uveitis. Of eight parameters examined, only baseline body weight predicted the development of uveitis by both univariate and multivariate analyses (P = .001). The incidence of uveitis was 14% in patients weighing >65 kg, 45% in patients between 55 and 65 kg, and 64% in patients <55 kg. Concomitant therapy with fluconazole, a drug known to raise serum rifabutin concentrations, was not associated with an increased incidence of uveitis. The risk of uveitis was markedly reduced when rifabutin was given at 300 mg daily in combination with clarithromycin and ethambutol.

Evaluation of an approach for adults with profound learning difficulties

A local day care unit for adults with profound learning disabilities is a popular community project. It receives many visits from students and volunteers and is also visited by a variety of support staff. The presence of these visitors makes an impact on the Unit's communication environment. A nursing and speech and language therapy project used photography to address the visitors' perceptions of the clients' communication and identify the visitors' information needs about the clients' communication skills. As a result of this evaluation the induction policy was changed and the leaflets were introduced. The time commitment to the initial project for therapy and nursing staff is discussed in relation to the effective and alternative use of therapeutic time for this client group.

Effects of peroxide on the fluorescence of the Ca2+ probe Fluo 3 and the pH probe BCECF

Fluorescence probes are invaluable tools in monitoring intracellular ion concentrations. They have also been used for studying how reactive oxygen species alter these concentrations and yet there are no studies indicating how reactive oxygen species directly affect the characteristics of the probes. Our concern was that if reactive oxygen were to affect characteristics of these probes, these measurements would be inconsequential. Therefore, we examined the effects of peroxide on the Ca2+-sensitive dye Fluo 3 and the pH sensitive dye BCECF. Peroxide concentrations below 10 mM did not alter fluorescence or binding characteristics of either dye. Since the concentrations of peroxide used in most pathophysiological experiments are in the micromolar range, we conclude that these probes are appropriate for monitoring the effects of peroxide on intracellular ion concentrations.