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31.
Bart D. Maes Wim Lemahieu Dirk Kuypers Pieter Evenepoel Willy Coosemans Jacques Pirenne Yves F. CH. Vanrenterghem 《American journal of transplantation》2002,2(10):989-992
Diarrhea is the most frequently reported adverse event in patients treated with mycophenolate mofetil. Twenty-six renal transplant patients on a mycophenolate mofetil-based immunosuppressive regime with persistent afebrile diarrhea were examined. Diarrhea caused a significant rise in FK-506 trough levels despite intake of stable doses, necessitating FK-506 dose reductions of 30% to obtain pre-diarrhea trough levels. In contrast, trough levels of cyclosporine A remained stable without dose adjustments. This suggests that absorption and/or metabolism is differentially altered for FK506 compared with cyclosporine A in patients with diarrhea. In nine patients mycophenolate mofetil was reduced or stopped because of persistent diarrhea without identifiable cause. This resulted in end-stage renal disease because of chronic rejection in two patients, and in acute rejection in two patients, all taking FK506 and steroids. Therefore, dose adjustments of FK506 in patients with diarrhea must be carefully monitored, especially when doses of mycophenolate mofetil are also reduced. 相似文献
32.
Proteolytic Processing Mechanisms in the Biosynthesis of Neuroendocrine Peptides: The Subtilisin-like Proprotein Convertases 总被引:1,自引:0,他引:1
Yves Rouill Stephen J. Duguay Kaare Lund Machi Furuta Qiuming Gong Gregory Lipkind Anthony A. Oliva Jr. Shu Jin Chan Donald F. Steiner 《Frontiers in neuroendocrinology》1995,16(4)
The recent discovery of a novel family of precursor processing endoproteases has greatly accelerated progress in understanding the complex mechanisms underlying the maturation of prohormones, neuropeptides, and many other precursor-derived proteins. At least six members of this family have been found thus far in mammalian species, several having alternatively spliced isoforms, and related enzymes have been identified in many invertebrates, including molluscs, insects, nematodes, and coelenterates. The proprotein convertases are all dependent on calcium for activity and all possess highly conserved subtilisin-like domains with the characteristic catalytic triad of this serine protease (ordered Asp, His, and Ser along the polypeptide chain). Two members of this family, PC2(SPC2) and PC1/PC3(SPC3), appear to play a preeminent role in neuroendocrine precursor processing. Both convertases are expressed only in the brain and in the extended neuroendocrine system, while another important family member—furin/PACE (SPC1)—is expressed more ubiquitously, in almost all tissues, and at high levels in liver. SPC2 and SPC3 exhibit acidic pH optima and other properties which enhance their activity in the acidic, calcium-enriched environment of the dense-core secretory granules of the regulated pathway in neuroendocrine cells, while furin has a neutral pH optimum and is localized predominantly to the trans Golgi network where it is retained by a C-terminal transmembrane domain. Furin processes a wide variety of precursors in the constitutive pathway, such as those of growth factors, receptors, coagulation factors, and viral glycoproteins. Recent findings on the processing of proopiomelanocortin, proinsulin, proglucagon, and several other neuroendocrine precursors by SPC2 and SPC3 are discussed, along with information on the structure, properties, evolution, developmental expression, and regulation or the convertases. An inherited defect in the fat/fat mouse which affects the processing of proinsulin, and probably also many other prohormones, due to a point mutation in carboxypeptidase E has recently been identified and has begun to provide new insights into the functional integration of the individual processing steps. 相似文献
33.
Prof. Paul Bonnevialle Yves Bellumore Michel Mansat 《Operative Orthopadie und Traumatologie》1996,8(4):243-251
Summary
Goal of Surgery Stable internal fixation of extraarticular proximal humeral fractures.
Indications Extraarticular fractures angulated more than 30° which can be reduced closely or through a small incision.
Epiphysiolysis.
Fracture-dislocation of the humeral head.
Contraindications Pathological fractures.
Four part fractures.
Segmental fractures of the humerus.
Positioning and Anaesthesia Supine; the affected shoulder overhanging the edge of the table and supported by a radiolucent board.
General or regional anaesthesia.
Surgical Technique Closed pinning of two part and certain three part fractures of the proximal humerus being displaced, unstable, and mainly
at the metaphyseal level.
Introduction of Kirschner wires through a diaphyseal window and advancement into the proximal fragments after reduction which
is controlled by image intensification.
Postoperative Management Temporary immobilization in a sling.
Passive and active assisted movements after a few days.
Active movements after 2 weeks.
Removal of wires after 3 months.
Possible Complications Fracture of the humerus at the site of the cortical window. Injury to the radial nerve.
Results 32 patients, mean age 49 years, 30 two part fractures and 2 three part fractures. Number of Kirschner wires used: 3 to 6,
mean 4. Two out of 3 patients complained of pain at the site of wire insertion. All fractures consolidated. No avascular necrosis
nor infection.
Complications: Partial loss of internal fixation in 3 patients. One fracture of the humeral shaft. Sympathetic reflex dystrophy
in 3 patients. Half of the patients had a normal range of motion. Time of follow-up: 6 to 24 (mean 10) months.
Division of Orthopaedics and Traumatology, Purpan Hospital, Toulouse, France. 相似文献
34.
Comparative effects of ischemia and acute hypoxemia (PaO2 = 24 mm Hg) were studied in anesthetized cats on afferents from the tibialis anterior limb muscle. Metaboreceptors (groups III and IV fibers) and mechanoreceptors were identified by their activation by an intraarterial injection of lactic acid (LA) or high-frequency vibrations (HFV) applied to the extremity of the muscle tendon, respectively. Ischemia and hypoxemia exerted opposite influences on the two categories of muscle afferents: they depressed the response of mechanoreceptors to HFV, but markedly enhanced the spontaneous tonic activity of metaboreceptors. The effects of hypoxamia were delayed but slightly greater and lasted longer during the recovery period than those exerted by ischemia. The inhibitory action on mechanoreceptors exerted by a reduced oxyden supply to muscle is interpreted as a result from local acidosis. Indeed, under normoxic conditions, a LA bolus injection during the HFV test also reduced the firing rate of these receptors. © 1993 John Wiley & Sons, Inc. 相似文献
35.
Yves de Roten Mlanie Fischer Martin Drapeau Vronique Beretta Ueli Kramer Nathalie Favre Jean‐Nicolas Despland 《Clinical psychology & psychotherapy》2004,11(5):324-331
Early therapeutic alliance is usually measured by the rating of a single session (between the third and the fifth sessions). However, there is a strong argument in favor of viewing early alliance as a developing process. This study examined the relationship between patient's rating of the helping alliance (HAq) at each session and therapy outcome. This comparison was repeated using patterns of alliance over the course of treatment. Patterns of therapeutic alliance development were detected by clustering ratings of a sample of N = 70 outpatients across four sessions of very brief psychotherapeutic intervention. Cluster analysis revealed two main patterns (shapes) of alliance development: (i) stable alliance, and (ii) linear growth pattern. These patterns are more predictive of symptom improvement and social adjustment than single ratings, whereas single ratings measuring the strength of alliance are more correlated with patient's satisfaction. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
36.
Focal expression and final activity of matrix metalloproteinases may explain irregular dysfunctional endometrial bleeding 总被引:11,自引:0,他引:11
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Galant C Berlière M Dubois D Verougstraete JC Charles A Lemoine P Kokorine I Eeckhout Y Courtoy PJ Marbaix E 《The American journal of pathology》2004,165(1):83-94
Irregular dysfunctional bleeding of the endometrium (ie, metrorrhagia without organic lesion) is common in women, whether treated or not with ovarian hormones. Several matrix metalloproteinases (MMPs) become normally expressed and/or activated at menstruation and cause extracellular matrix breakdown. We therefore explored whether episodes of irregular dysfunctional bleeding could be associated with untimely MMP activity. By histology, foci of stromal breakdown were exclusively found in the endometrium of metrorrhagic women at bleeding. In these foci, 1) expression of estrogen receptor-alpha and progesterone receptor was altered; 2) collagenase-1 (MMP-1), stromelysin-1 (MMP-3), and gelatinase B (MMP-9) became detected in stromal cells, together with MMP-9 in neutrophils; and 3) gelatinase A (MMP-2) was more expressed and immunolocalized at the membrane of stromal cells. By biochemistry, endometrial lysates from nonbleeding metrorrhagic patients contained more latent and active MMP-2 and -9 than age-matched controls; at bleeding, collagenase activity, MMP-9, and active MMP-2 were strikingly increased whereas tissue inhibitor of metalloproteinases-1 (TIMP-1) was considerably decreased. As a functional assay, in situ gelatin zymography revealed large areas of gelatinolytic activity only in endometrium of bleeding patients. Altogether, these results strongly suggest that inappropriate focal expression and activation of several MMPs, combined with decreased inhibition, trigger irregular dysfunctional endometrial bleeding. 相似文献
37.
Persistent increase in the incidence of acute male urethritis diagnosed in general practices in France
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Vronique Massari Yves Dorlans Antoine Flahault 《The British journal of general practice》2006,56(523):110-114
BACKGROUND: At-risk sexual behaviour seems to have increased in Europe, possibly due to the reassuring efficacy of highly active antiretroviral treatments. AIM: To follow, from 1990 to 2003, in France, the trends in the incidence of acute male urethritis diagnosed in general practice, a marker of at-risk sexual behaviour. DESIGN OF STUDY: Electronic disease surveillance. SETTING: General practices located all over mainland France. METHOD: The GPs of the French Sentinelles network reported, via online computer systems, the acute urethritis cases they diagnosed, and for each case the characteristics of the patients. RESULTS: After a striking decrease between 1990 and 1995 from 460 per 100 000 men aged 15-64 years (95% confidence interval [CI] = 390 to 520) to 180 (95% CI = 150 to 200), when antiretroviral drugs became available on the French market, the incidence of acute male urethritis stopped decreasing. Between 1996 and 2003, it may have risen again from 190 per 100 000 men (95% CI = 160 to 210) to 325 per 100 000 men (95% CI = 280 to 370) aged 15-64 years. The percentage of homosexual/bisexual men among the cases reported was higher than in the general population (10% versus 4%, P<0.001). Homosexual/bisexual patients were younger than heterosexual patients (34 versus 37 years, P = 0.04), more of them had a discharge (88% versus 59%, P<0.001), a history of sexually transmitted disease (65% versus 32%, P<0.001), and at least two sexual partners (74% versus 38%, P<0.001). The most frequent pathogens were Chlamydia trachomatis (25%), Neisseria gonorrhoea (21%), Mycoplasma genitalium (8%), Ureaplasma urealyticum (5%), Trichomonas vaginalis (3%) and other bacteria (32%). Presence of co-infections was observed in 8.3% of patients. CONCLUSIONS: This increase in the incidence of urethritis, shows that the sexual health of men has worsened in France, and calls for urgent new preventive measures. 相似文献
38.
DNA synthesis and release was studied in unstimulated splenocytes of strains of mice known to develop spontaneous systemic lupus erythematosus (SLE)-like disease and in non-SLE age- and sex-matched strains as well. Newly synthesized DNA was measured as total acid-insoluble radioactive material present in cell pellet plus supernatant of unstimulated 0–72 h cell cultures [3H]thymidine-pulsed, whereas DNA release was measured as amount of acid-precipitable radioactivity found in supernatant of those cultures. In all strains known to develop spontaneous murine SLE the amount of newly synthesized DNA was 1.3–2.1-fold increased when compared to normal strains studied concomitantly. Furthermore, a significant increase in DNA release into medium, unrelated to cell viability, was observed in those strains as well. These observations clearly demonstrate different metabolic rates of synthesis and release of DNA in murine SLE. This difference suggests the existance of an underlying mechanism responsible for extracellular DNA abundancy, which may be important for the formation of circulating DNA-anti-DNA immune complexes. 相似文献
39.
A technique that allowsin vivo measurements of the specific impedance of brain structures is analysed and implemented. This technique uses the 4-electrode method. The system includes an optically isolated current source and an interchangeable electrode module. Tests on the measuring system, including the electrodes and calibration procedures, are presented. Experiments in media of known resistivity and in cat brains define the present limits of the spatial resolution. 相似文献
40.
In normal adult rats some germ cells degenerate at several vulnerable steps of spermatogenesis. These are the type A spermatogonia, midpachytene spermatocytes, primary and secondary spermatocytes which degenerate during their respective maturation divisions and step 7 and 19 spermatids. In the present study, these degenerating cells were examined under the electron microscope, and their frequency was determined in toluidine blue stained semithin sections of testes from normal, hypophysectomized (at 5.5 days after operation) and hypophysectomized rats injected with FSH and LH separately or in combination. With the exception of the step 19 spermatids, the degenerating germ cells underwent necrosis in vacuolated spaces delimited by Sertoli cells. In the case of the affected step 19 spermatids, an apical cytoplasmic process of the Sertoli cell initially ensheathed a long segment of their flagellum, and then each degenerating cell was drawn deep in the seminiferous epithelium where it was phagocytozed by the Sertoli cell. Soon after hypophysectomy the incidence of degenerating mid-pachytene spermatocytes, step 7 and 19 spermatids which are present in stages VII or VIII of the cycle of the seminiferous epithelium, increased significantly. In contrast the number of degenerating primary or secondary spermatocytes during the meiotic divisions seen in stage XIV of the cycle or of any other germinal cell was not significantly modified. While the injection of FSH alone had no influence on the number of degenerating cells in hypophysectomized rats, injections of LH at the two doses administered (0.7 μg or 20 μg) reduced significantly the number of degenerating cells seen in stages VII-VIII of the cycle; combined injections of FSH and LH (20 μg) reduced the number of these degenerating cells to the normal low values. Thus it appeared that the mid-pachytene spermatocytes and the step 7 and 19 spermatids, all present in the adluminal compartment of the seminiferous epithelium in stages VII or VIII of the cycle, were more sensitive to the presence of absence of gonadotropic hormones than the other germ cells present in the seminiferous epithelium. 相似文献