Improved method for harvesting human Schwann cells from mature peripheral nerve and expansion in vitro

The pharmacological profile of a novel dual inhibitor, tepoxalin and of its carboxylic acid metabolite on cyclooxygenase and lipoxygenase pathways was evaluated by in vitro incubation with synovial tissue. Tissue specimens obtained at surgery in rheumatoid arthritis (RA, n = 10) or osteoarthritis (OA, n = 11) patients were incubated. Tepoxalin (10(-7), 10(-6), 10(-5) M) decreased eicosanoid release calculated in % of tyrode control for OA: LTC4 to 71-33%, 6-keto-PGF1a to 37-20%, PGE2 to 29-6%. For RA: LTC4 to 56-22%, 6-keto-PGF1a to 43-22%, PGE2 to 57-32%. Similarly, its metabolite (10(-7), 10(-5)M) decreased release in OA: LTC4 to 99 and 60%, PGE2 to 42 and 20%, 6-keto-PGF1a to 54 and 25%. In RA:LTC4 to 81 and 45%, PGE2 to 61 and 30%, 6-keto-PGF1a to 46 and 18%. Significance (P < 0.05) was achieved for all but 1 group (LTC4 metabolite at 10(-7)M vs tyrode). In summary a marked and dose dependent decrease of LT and PG release was obtained when incubating the dual inhibitor tepoxalin and its active carboxylic acid metabolite with synovial tissue at doses expected to be reached in the joint during therapy.     

Multiple solution conformations of the integrin-binding cyclic pentapeptide cyclo(-Ser-D-Leu-Asp-Val-Pro-). Analysis of the (phi, psi) space available to cyclic pentapeptides

The aqueous solution structure of the cyclic pentapeptide cyclo(-Ser-D-Leu-Asp-Val-Pro-) has been determined by two-dimensional 1H-NMR spectroscopy, combined with a conformational search and distance-geometry calculations. As many as five conformers in slow exchange were observed, and the rate of interconversion between components was measured from the build-up rates of exchange peaks. NMR data allowed the structures of the two predominant conformers to be determined. The major component (66%) contained a cis-proline as part of a type-VIa2 beta-turn encompassing residues Asp-Val-cis-Pro-Ser. The second component (16%) contained only trans-amide bonds, and a type-VIII beta-turn formed by residues Val-Pro-Ser-D-Leu. These structures are discussed in relation to the (phi, psi), space available to the cyclic pentapeptide, determined by a conformational search, and in relation to previously published cyclic-pentapeptide structures. The molecule exhibits activity in a scintillation-proximity assay for the inhibition of the interaction between the integrin very-late antigen-4 (VLA-4; alpha 4 beta 1) and vascular-cell-adhesion molecule-1 (VCAM-1). The structure/activity relationship of the LDV sequence is discussed and related to the recently published X-ray structure of VCAM-1. The relevance of the work to the design of anti-inflammatory drugs is discussed.     

Targeting attention on local vulnerabilities using an integrated index approach: the example of the climate vulnerability index.

It is known that climate impacts can have significant effects on the environment, societies and economies. For human populations, climate change impacts can be devastating, giving rise to economic disruption and mass migration as agricultural systems fail, either through drought or floods. Such events impact significantly, not only where they happen, but also in the neighbouring areas. Vulnerability to the impacts of climate change needs to be assessed, so that adaptation strategies can be developed and populations can be protected. In this paper, we address the issue of vulnerability assessment through the use of an indicator approach, the climate vulnerability index (CVI). We show how this can overcome some of the difficulties of incommensurability associated with the combination of different types of data, and how the approach can be applied at a variety of scales. Through the development of nested index values, more reliable and robust coverage of large areas can be achieved, and we provide an indication of how this could be done. While further work is required to improve the methodology through wider application and component refinement, it seems likely that this approach will have useful application in the assessment of climate vulnerability. Through its application at sub-national and community scales, the CVI can help to identify those human populations most at risk from climate change impacts, and as a result, resources can be targeted towards those most in need.     

Dubin calls on CMPA to eliminate fee differentials, adopt flat fee for all physicians

PURPOSE: To examine vascular associations with pseudoexfoliation syndrome in view of the wide-spread elastosis now demonstrated in this disorder that affects many tissues, including vessel walls. METHODS: The Blue Mountains Eye Study is a population-based study of eye disease in an area west of Sydney, Australia. Of 4433 eligible persons aged 49 years or older, 3,654 (82.4%) participated. Signs of pseudoexfoliation were graded clinically, after excluding 108 people who had bilateral cataract surgery. RESULTS: Pseudoexfoliation was present in 81 (2.3%) of 3546 participants aged 49 years or older. The prevalence of pseudoexfoliation increased with age and was higher in women and in people with glaucoma. Pseudoexfoliation was statistically significantly associated with a history of angina or hypertension or a combined history of angina, acute myocardial infarction, or stroke. CONCLUSION: Slit-lamp signs of pseudoexfoliation may identify individuals with an increased vascular risk.     

A cholera toxin-sensitive guanyl nucleotide binding protein mediates the movement of pituitary luteinizing hormone into a releasable pool: loss of this event is associated with the onset of homologous desensitization to gonadotropin-releasing hormone

Cholera toxin (CTX; 5 micrograms/ml), but not pertussis toxin (100 ng/ml), when preincubated with pituitary cells for 18 h, enhances the percentage of cellular LH released in response to continuous or pulsatile administration of 5 x 10(-9) M GnRH. This effect occurs without increasing total (intracellular plus extracellular) LH, indicating that it is best explained by redistribution of LH from a nonreleasable to a releasable pool. This site of action is consistent with the observation that CTX-pretreated cells are also sensitized to stimulation of LH release by the Ca2+ ionophore A23187. The observations that CTX stimulates the production of cAMP in these cells and that the sensitizing action of CTX is mimicked by (Bu)2cAMP (1 mM) are consistent with the view that a CTX-stimulated guanyl nucleotide binding protein, capable of activating adenylyl cyclase, is mediating this sensitization. We used a perifused cell system to show that the movement of LH into a releasable pool is lost with the onset of homologous desensitization due to high pulse frequency or constant administration of GnRH (5 x 10(-9) M, continuous or a pulse each 15 min). Sensitization to CTX is restored by stimulation with a high concentration of GnRH (10(-6) M) or by resetting the pulse frequency to the rate measured in vivo (a pulse each 90 min). Both of these treatments also circumvent the desensitized state, restoring LH release. These results identify a novel lesion associated with the development of desensitization in the gonadotrope and support the role of a CTX-sensitive guanyl nucleotide binding protein in regulation of pituitary responsiveness to GnRH.     

Rapid infusion system for neurosurgical treatment of massive intraoperative hemorrhage

Using an illustrative case of severe closed head injury that resulted in a posterior fossa epidural hematoma (EDH) and supratentorial epidural/subdural hematomas (SDH), the massive blood losses associated with operative repair of the torn sigmoid sinus and the significant fluid losses associated with refractory diabetes insipidus were treated by the intraoperative use of the Rapid Infusion System (RIS, Haemonetics). The RIS can rapidly infuse warm blood, crystalloid, or colloid at rates up to 1.5 L/min, thereby limiting the commonly associated hypotension, hypothermia, and coagulopathies. During the suboccipital craniectomy for evacuation of the EDH and repair of the sigmoid sinus, the patient required 18 units of blood replacement secondary to a large tear in the sigmoid sinus. During a separate craniotomy for evacuation of the SDH, the patient also developed diabetes insipidus, which increased the operative fluid replacement to 39 L. Despite these massive blood and fluid losses, the RIS limited the hypotension to less than 2 min and prevented hypothermia and the frequently associated coagulopathies. When used in a neurosurgical setting associated with massive blood and/or fluid losses, the RIS accomplishes three important objectives: (1) rapid infusion of intravenous fluids for maintaining perfusion pressure, (2) rapid warming of fluids despite high intravenous infusion rates of cold crystalloids, thereby preventing intraoperative hypothermia, and (3) continuous monitoring of infusion rates and totals.     

Glucagon-like peptide I enhances the insulinotropic effect of glibenclamide in NIDDM patients and in the perfused rat pancreas

OBJECTIVE: To investigate the acute effects of glibenclamide and glucagon-like peptide I (GLP-I) and their combination in perfused isolated rat pancreas and in patients with secondary failure to sulfonylureas. RESEARCH DESIGN AND METHODS: Rat islets were perfused with 10 nmol/l GLP-I in combination with 2 mumol/l glibenclamide. In human experiments, GLP-I (0.75 pmol. kg-1.min-1) was given as a continuous infusion during 240 min, while glibenclamide (3.5 mg) was administered orally. Eight patients participated in the study (age 57.6 +/- 2.7 years, BMI 28.7 +/- 1.5 kg/m2, mean +/- SE). In all subjects, blood glucose was first normalized by insulin infusion administered by an artificial pancreas (Biostator). RESULTS: GLP-I increased the insulinotropic effect of glibenclamide fourfold in the perfused rat pancreas. In human experiments, treatment with GLP-I alone and in combination with glibenclamide significantly decreased basal glucose levels (5.1 +/- 0.4 and 4.5 +/- 0.1 vs. 6.0 +/- 0.3 mmol/l, P < 0.01), while with only glibenclamide, glucose concentrations remained unchanged. GLP-I markedly decreased total integrated glucose response to the meal (353 +/- 60 vs. 724 +/- 91 mmol.l-1. min-1, area under the curve [AUC] [-30-180 min], P < 0.02), whereas glibenclamide had no effect (598 +/- 101 mmol.l-1. min-1, AUC [-30-180 min], NS). The combined treatment further enhanced the glucose lowering effect of GLP-I (138 +/- 24 mmol. l-1.min, AUC [-30-180 min], P < 0.001). GLP-I, glibenclamide, and combined treat-stimulated meal-induced insulin release as reflected by insulinogenic indexes (control 1.44 +/- 0.4; GLP-I 6.3 +/- 1.6, P < 0.01; glibenclamide 6.8 +/- 2.1, P < 0.01; combination 20.7 +/- 5.0, P < 0.001). GLP-I inhibited basal but not postprandial glucagon responses. Using paracetamol as a marker for gastric emptying rate of the test meal, treatment with GLP-I decreased gastric emptying at 180 min by approximately 50% compared with the control subjects (P < 0.01). CONCLUSIONS: In acute experiments on overweight patients with NIDDM, GLP-I exerted a marked antidiabetogenic action on the basal and postprandial state. The peptide stimulated insulin, suppressed basal glucagon release, and prolonged gastric emptying. The glucose-lowering effect of GLP-I was further enhanced by glibenclamide. This action may be at least partially accounted for by a synergistic effect of these two compounds on insulin release. Glibenclamide per se enhanced postprandial but not basal insulin release and exerted a less pronounced antidiabetogenic effect compared with GLP-I.     

Desire and efforts to quit smoking among cigarette smokers in Wisconsin

This research studied the desire and attempts of cigarette smokers in Wisconsin to quit smoking. Data were based on the 1993 Wisconsin Division of Health's Behavioral Risk Factor Surveillance System (BRFSS). Among the 23% of respondents who were current smokers, 79% said they wanted to quit smoking and 60% said they had quit smoking for a day or more in the preceding year. High rates of wanting to quit and having tried to quit were found in all demographic subgroups of smokers studied. Compared to lighter smokers, heavy cigarette smokers (20 or more cigarettes per day) were less likely to have tried quitting in the past year, but were almost as likely to want to quit. These results demonstrate the great demand for smoking cessation services among smokers in Wisconsin and support for efforts to increase the use and effectiveness of these interventions.     

When 3-year-olds pass the appearance–reality test.

68 3-yr-olds received a standard appearance–reality task along with either a trick task, in which the appearance question was placed in the context of a deceptive game, or a reduced information processing task, in which a dual object (e.g., a sponge-rock) was presented along with an object that matched the dual object's identity (a sponge) and one that matched the dual object's appearance (a rock). Children were more likely to pass either the trick or reduced information processing task and fail the standard than the reverse. Thus, 3-yr-olds can grasp the distinction between appearance and reality (a) when their goal is to trick someone, which may prime them to think about the other's mental state, and (b) when they do not need to hold conflicting object identities in mind at the same time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ornithine-delta-aminotransferase expression and ornithine metabolism in cultured epidermal keratinocytes: toward metabolic sink therapy for gyrate atrophy

There is now strong evidence that the chorioretinal degeneration associated with ornithine-delta-aminotransferase (OAT) deficiency is a consequence of hyperornithinemia. Therefore development of a metabolic system for clearing ornithine from the circulation is being pursued as a potential treatment. The skin is considered an attractive location for such a metabolic system because autologous cells can be safely and easily utilized. This study was undertaken to determine the ornithine metabolizing capacity of epidermal keratinocytes expressing normal and superphysiologic amounts of OAT. The data show that overexpression of OAT in keratinocytes cultured from a gyrate atrophy patient restores ornithine metabolism and results in a rate of ornithine disappearance from the medium that is significantly higher than the rate of disappearance from the medium bathing normal keratinocytes. In addition, OAT activity determined in soluble protein prepared from sonicates suggests that the capacity to maintain plasma ornithine within the normal range is contained within an accomplishable graft of keratinocytes overexpressing OAT. However, the actual rate of ornithine disappearance from the media was significantly less than predicted from enzyme activity assays. Following ornithine metabolite production by intact cells suggests that ornithine metabolism is limited primarily by clearance of downstream metabolites, as opposed to substrate delivery.