73 research outputs found

    Principal noncommutative torus bundles

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    In this paper we study continuous bundles of C*-algebras which are non-commutative analogues of principal torus bundles. We show that all such bundles, although in general being very far away from being locally trivial bundles, are at least locally trivial with respect to a suitable bundle version of bivariant K-theory (denoted RKK-theory) due to Kasparov. Using earlier results of Echterhoff and Williams, we shall give a complete classification of principal non-commutative torus bundles up to equivariant Morita equivalence. We then study these bundles as topological fibrations (forgetting the group action) and give necessary and sufficient conditions for any non-commutative principal torus bundle being RKK-equivalent to a commutative one. As an application of our methods we shall also give a K-theoretic characterization of those principal torus-bundles with H-flux, as studied by Mathai and Rosenberg which possess "classical" T-duals.Comment: 33 pages, to appear in the Proceedings of the London Mathematical Societ

    Anti-dyslipidemic and Antioxidant Potentials of Methanol Extract of Kalanchoe crenata Whole Plant in Streptozotocin-induced Diabetic Nephropathy in Rats

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    Purpose: The activity of the methanol extract of the whole plant of Kalanchoe crenata (MEKC) was studied for the treatment of diabetes-induced nephropathy in rats.Methods: Five-day old Wistar rats received a single intraperitoneal streptozotocin injection (90 ìg/kg body weight) to induce diabetes. Kidney disease onset in the rats was observed six weeks after diabetes induction. The rats were orally administered MEKC (0, 50 and 68 mg/kg) or glibenclamide (5 mg/kg), once daily for 6 weeks. Blood and urine glucose, proteins, lipids, creatinine, malondialdehyde (MDA), superoxide dismutase (SOD) and catalase (CAT) were then evaluated.Results: After 6 weeks of treatment, 50 and 68 mg/kg MEKC, and glibenclamide significantly (p < 0.01) decreased glycaemia (-35, -44 and -39 %), glycosuria (-38, -47 and -61 %) and proteinuria (-82, -80 and-72 %) in diabetes-nephropathic rats. The extract (68 mg/kg) decreased MDA by up to -44 % (blood), -35 % (liver) and -34 % (kidney); increased SOD up to 257 % (blood), 116 % (liver) and 118 % (kidney); and CAT by up to 176 % (blood), 78 % (liver) and 96 % (kidney) in the rats, compared with nephropathic control. The extract (50 and 68 mg/kg, respectively) lowered (p < 0.01) total cholesterolemia (-24 and - 27 %), blood triglycerides (-55 and -54 %), blood LDL cholesterol (-48 and -59 %), but increased blood HDL cholesterol (71 and 58 %). Overall, atherogenic index was decreased by 31 %.Conclusion: The results indicate that MEKC holds promise for the development of a standardized phytomedicine for diabetes mellitus and kidney disease treatment.Keywords: Diabetes, Dyslipidemia, Antioxidant, Kalanchoe crenata extract, Nephropathy

    The K-theory of free quantum groups

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    In this paper we study the K -theory of free quantum groups in the sense of Wang and Van Daele, more precisely, of free products of free unitary and free orthogonal quantum groups. We show that these quantum groups are K -amenable and establish an analogue of the Pimsner–Voiculescu exact sequence. As a consequence, we obtain in particular an explicit computation of the K -theory of free quantum groups. Our approach relies on a generalization of methods from the Baum–Connes conjecture to the framework of discrete quantum groups. This is based on the categorical reformulation of the Baum–Connes conjecture developed by Meyer and Nest. As a main result we show that free quantum groups have a γ -element and that γ=1 . As an important ingredient in the proof we adapt the Dirac-dual Dirac method for groups acting on trees to the quantum case. We use this to extend some permanence properties of the Baum–Connes conjecture to our setting

    Entomophtoromycose rhino faciale: A propos d'un cas

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    Les auteurs rapportent un cas rare d'entomophtoromycose rhinofaciale avec les difficultés diagnostiques et thérapeutiques liées à cette mycose exotique. L'intérêt de la biopsie devant la présentation clinique d'une tumeur centro-faciale est rappelé pour éviter tout retard diagnostic. Clinics in Mother and Child Health Vol. 3(1) 2006: 495-49

    Gynecological cancer profile in the Yaounde population, Cameroon

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    This population-based retrospective study was carried out in the Yaounde Population Cancer Registry (YPCR) at the General Hospital Yaounde, Cameroon. The aim was to find out the socio-economic, epidemiologic, anatomic and pathologic profile of patients with gynecological cancers in the Yaounde population. The database of the registry was reviewed between January 1, 2004 and June 30 2005 (18 months). All cases of microscopically confirmed gynecological cancers registered within this period were recruited. Defined as gynecological cancers are cancers of the breast (in women), ovary, uterine corpus, vulva, vagina, and cervix. The results showed that gynecological cancers have a monthly incidence of 30 cases. Whereas cancers of the placenta, vagina, breast, and ovary affect younger adults, endometrial, vulval and cervical cancers predominate in the elderly. 58% of the women were aged between 34-54 years. Most patients are from the West (30.55%), Centre (28.90%) and Littoral (10.00%) provinces respectively. The commonest cancers are the breast (48.12%), cervix (40.18%), and ovary (5.82%) at respective average ages of 42.80 years (19-76 years range), 53.08 years (24-78 years range) and 44.22 years (9-75 years range). Cancers of the uterine corpus are rare. Most patients were illiterate, of low to average socio-economic status, presenting at advanced stage of disease. Cancer of the breast is common in the upper social class; while malignancies of the cervix, endometrium, and vagina predominate in the low and middle classes. Only 17.5% of our patients had been previously screened for any form of cancer prior to present disease. We had no data on family history of cancer. We recommend intensive public health education and sensitization of women on primary and secondary prevention especially for cervical and breast cancers. Gynaecological services should be vulgarized and existing ones improved with defined referral and counter referral systems. Further in-depth studies to document trends on cancer survival are recommended. Clinics in Mother and Child Health Vol. 3(1) 2006: 437-44

    Role of the monocarboxylate transporter MCT1 in the uptake of lactate during active recovery

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    Purpose We assessed the role of monocarboxylate transporter 1 (MCT1) on lactate clearance during an active recovery after high-intensity exercise, by comparing genetic groups based on the T1470A (rs1049434) MCT1 polymorphism, whose influence on lactate transport has been proven. Methods Sixteen young male elite field hockey players participated in this study. All of them completed two 400 m maximal run tests performed on different days, followed by 40 min of active or passive recovery. Lactate samples were measured immediately after the tests, and at min 10, 20, 30 and 40 of the recoveries. Blood lactate decreases were calculated for each 10-min period. Participants were distributed into three groups according to the T1470A polymorphism (TT, TA and AA). Results TT group had a lower blood lactate decrease than AA group during the 10?20 min period of the active recovery (p = 0.018). This period had the highest blood lactate for the whole sample, significantly differing from the other periods (p ? 0.003). During the passive recovery, lactate declines were constant except for the 0?10-min period (p ? 0.003), suggesting that liver uptake is similar in all the genetic groups, and that the difference seen during the active recovery is mainly due to muscle lactate uptake. Conclusions These differences according to the polymorphic variant T1470A suggest that MCT1 affects the plasma lactate decrease during a crucial period of active recovery, where the maximal lactate amount is cleared (i.e. 10?20 min period)

    The kinetics of lactate production and removal during whole-body exercise

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    <p>Abstract</p> <p>Background</p> <p>Based on a literature review, the current study aimed to construct mathematical models of lactate production and removal in both muscles and blood during steady state and at varying intensities during whole-body exercise. In order to experimentally test the models in dynamic situations, a cross-country skier performed laboratory tests while treadmill roller skiing, from where work rate, aerobic power and blood lactate concentration were measured. A two-compartment simulation model for blood lactate production and removal was constructed.</p> <p>Results</p> <p>The simulated and experimental data differed less than 0.5 mmol/L both during steady state and varying sub-maximal intensities. However, the simulation model for lactate removal after high exercise intensities seems to require further examination.</p> <p>Conclusions</p> <p>Overall, the simulation models of lactate production and removal provide useful insight into the parameters that affect blood lactate response, and specifically how blood lactate concentration during practical training and testing in dynamical situations should be interpreted.</p
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