Interaction of kunjin virus with octyl-D-glucoside extracted Vero cell plasma membrane

Initial experiments using whole cells have shown that there were specific and saturable interactions between kunjin (KUN) virus and receptor molecules on the Vero cell surfaces. Solubilisation of Vero cell plasma membranes with octyl-D-glucoside (OG) yielded an extract which also interacted specifically with KUN virus. This was proven using electron microscopy. When the virus-OG-extract complex was exposed onto Vero cell monolayers, no KUN virus was observed to enter into the whole cells. This would imply that there was virus-receptor interaction with the OG-extract leaving no free virus to attach to the whole cells. The attachment kinetics of KUN virus was studied further using the Scatchard analysis which indicated the involvement of more than one interactive macromolecule in the attachment event.     

Involvement of sphingosine 1-phosphate in nerve growth factor-mediated neuronal survival and differentiation

Sphingolipid metabolites, such as ceramide and sphingosine-1-phosphate (SPP), are emerging as a new class of second messengers involved in cellular proliferation, differentiation, and apoptosis. Nerve growth factor (NGF), a neurotrophic factor for pheochromocytoma PC12 cells, induced a biphasic increase in the activity of sphingosine kinase, the enzyme that catalyzes the formation of SPP. This activation was blocked by K252a, an inhibitor of tyrosine kinase A (trkA). A rapid 1.7-fold increase was followed by a marked prolonged increase reaching a maximum of fourfold to fivefold stimulation with a concomitant increase in SPP levels and a corresponding decrease in endogenous sphingosine levels. Levels of ceramide, the precursor of sphingosine, were only slightly decreased by NGF in serum-containing medium. However, NGF decreased the elevation of ceramide induced by serum withdrawal. Treatment of PC12 cells with SPP did not induce neurite outgrowth or neurofilament expression, yet it enhanced neurofilament expression elicited by suboptimal doses of NGF. Moreover, SPP also protected PC12 cells from apoptosis induced by serum withdrawal. To further substantiate a role for SPP in the cytoprotective actions of NGF, we found that N, N-dimethylsphingosine, a competitive inhibitor of sphingosine kinase, also induced apoptosis and interfered with the survival effect of NGF. These effects were counteracted by exogenous SPP. Moreover, other structurally related compounds, such as dihydrosphingosine 1-phosphate and lysophosphatidic acid, had no significant protective effects. Our results suggest that activation of sphingosine kinase and subsequent formation of SPP may play an important role in the differentiation and survival effects induced by NGF.     

Bax- and Bak-induced cell death in the fission yeast Schizosaccharomyces pombe

The dental profession faces educational, scientific, and ethical challenges in orofacial pain and headache. Past educational deficiencies are being addressed with guidance and recommendations from the AADS, the ADA, and the AAOP. With education and further research, many dental ethical questions in TMD will be resolved. The educational process must continue with a solid foundation in scientific basis provided in university settings. The appropriate use of TMD diagnostic machines, treatment modalities, and management of perpetuating factors such as sleep will evolve with the new knowledge of scientific discovery. These are some of the many challenges of orofacial pain and headache disorders that warrant special consideration.     

A hermeneutic analysis of the process of conducting clinical interviews

1. Although no right way to interview exists, an interviewer should develop a comfortable, personal style. 2. Allowing an interview to follow its own course while remembering the overall interview agenda will contribute to quality of the data. 3. Interviewing skills are enhanced as the interviewer develops a personal style and becomes comfortable as a practitioner.     

Prognostic significance of tumour markers in endometrial cancer

BACKGROUND: Steroid 5 alpha-reductase is implicated in the pathogenesis of benign prostatic hyperplasia (BPH). We studied the in vitro and in vivo effects of FR146687, a new inhibitor of 5 alpha-reductase. METHODS: Two isozymes of rat and human 5 alpha-reductases were expressed in 293 cells. In vivo effects of drugs were evaluated on rat and dog prostates. Castrated immature rats were injected with testosterone propionate (TP) or 5 alpha-dihydrotestosterone propionate (DHTP) to induce growth of the ventral prostates. Testosterone and 5 alpha-dihydrotestosterone (DHT) contents in rat and dog prostates were measured by gas chromatography-mass spectrophotometry (GC-MS). RESULTS: FR146687 showed noncompetitive inhibition in both isozymes and no inhibitory effects on other steroid oxidoreductases. In mature rats and castrated immature rats treated with TP, FR146687 dose-dependently reduced ventral prostate and seminal vesicle weight at doses above 0.1 mg/kg, while castrated immature rats treated with DHTP were not affected by FR146687. FR146687 showed more potent reduction of rat prostates than finasteride. DHT concentration in the prostates was significantly reduced when FR146687 was administered to rats and beagles. CONCLUSIONS: FR146687 is a dual inhibitor for 5 alpha-reductase isozymes and significantly reduced the growth and DHT content in the prostate.     

Compartment-ablation studies of GLUT4 distribution in adipocytes: evidence for multiple intracellular pools

The available data suggest that GLUT4 does populate the recycling endosomal system to some extent, but that a large proportion of the intracellular GLUT4 resides in a compartment that is devoid of transferrin receptors and may have properties more akin to specialized secretory vesicles. The study of the nature and biogenesis of this compartment will provide important insight into the mechanism by which insulin stimulates glucose transport. Further study of the role of the synaptobrevins in these distinct subcellular compartments will probably shed further light on the mechanism by which insulin stimulates GLUT4 translocation.     

APIC position paper: hepatitis C exposure in the health care setting. Association for Professionals in Infection Control and Epidemiology, Inc

The Association for Professionals in Infection Control and Epidemiology, Inc (APIC), is a multidisciplinary, voluntary, international organization of professionals who practice infection control and the application of epidemiology in all health settings. APIC is an international leader in prevention and control of infection transmission.     

Dental microwear of Griphopithecus alpani

The examination of microscopic dental wear allows inferences to be made about diet in extinct species. This study reconstructs the diet of Griphopithecus alpani, a 15 Ma fossil hominoid from the Miocene site of Pa?alar in north-western Turkey, using scanning electron microscopy (SEM) to examine the microscopic wear on its molar teeth. The microwear patterns of Griphopithecus are compared with those of three extant hominoid taxa-Gorilla gorilla gorilla, Pan troglodytes verus, and Pongo pygmaeus pygmaeus. The microwear on three occlusal wear surfaces is examined in this study, and sex and age differences are also included. Analysis of variance is performed on the following microwear variables-feature density, pit density, striation density, the ratio of pits relative to striations, pit widths, and striation widths. Griphopithecus has significantly higher microwear feature densities and higher percentages of pits than Gorilla. It also has larger pit frequencies and narrower striations than both Pan and Gorilla. There are no significant differences between the microwear patterns of Griphopithecus and Pongo. This suggests that the diet of Gripho-pithecus was more similar to that of Pongo, which consumes mainly fruit, and occasionally hard and unripe fruits and nuts, than to that of Pan and Gorilla. In addition, the high percentage of pits displayed by Griphopithecus may indicate that it was ingesting harder fruits and/or objects than the extant hominoids, although this is not a significant difference. There also are consistent variations in the microwear present on the three different wear facets examined in the study-Phase II facets display more microwear and pitting than the Phase I surface examined. The results of this study do not indicate variation in dental microwear according to sex or age.