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51.
Associated with a host of different diseases, pruritus is a cardinal symptom that poses an interdisciplinary diagnostic and therapeutic challenge. Over time, that symptom may progress independently of the initial cause, thus losing its function as a warning sign and turning into a clinically relevant disease of its own. In Germany, approximately 13.5 % of the general population are affected by chronic pruritus, with an incidence of 7 %. All forms of chronic pruritus require targeted treatment consisting of (a) diagnosis and management of the underlying disease, (b) dermatological treatment of primary or secondary (for example, dry skin, scratch lesions) symptoms, (c) symptomatic antipruritic treatment, and (d) psychological/psychotherapeutic treatment in case of an underlying or associated psychological or psychosomatic condition. Medical care of patients with chronic pruritus should therefore include an interdisciplinary approach, in particular with respect to diagnosis and therapy of the underlying disease as well as in terms of the management of treatment and adverse events. The objective of the present interdisciplinary guidelines is to define and standardize diagnostic and therapeutic procedures in patients with chronic pruritus. This is a short version of the current S2 guidelines on chronic pruritus. The long version may be found at www.awmf.org .  相似文献   
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Basic fibroblast growth factor (bFGF) is a hematopoietic cytokine that stimulates stromal and stem cell growth. It binds to a glycosylphosphatidylinositol (GPI)-anchored heparan sulfate proteoglycan on human bone marrow (BM) stromal cells. The bFGF- proteoglycan complex is biologically active and is released by addition of exogenous phosphatidylinositol-specific phospholipase C. In this study, we show the presence of an endogenous GPI-specific phospholipase D (GPI-PLD) that releases the bFGF-binding heparan sulfate proteoglycan and the variant surface glycoprotein (a model GPI-anchored protein) from BM cultures. An involvement of proteases in this process is unlikely, because released proteoglycan contained the GPI anchor component, ethanol-amine, and protease inhibitors did not diminish the release. The mechanism of release is likely to involve a GPI-PLD and not a GPI-specific phospholipase C, because the release of variant surface glycoprotein did not reveal an epitope called the cross- reacting determinant that is exposed by phospholipase C-catalyzed GPI anchor cleavage. In addition, phosphatidic acid (which is specifically a product of GPI-PLD-catalyzed anchor cleavage) was generated during the spontaneous release of the GPI-anchored variant surface glycoprotein. We also detected GPI-PLD-specific enzyme activity and mRNA in BM cells. Therefore, we conclude that an endogenous GPI-PLD releases bFGF-heparan sulfate proteoglycan complexes from human BM cultures. This mechanism of GPI anchor cleavage could be relevant for mobilizing biologically active bFGF in BM. An endogenous GPI-PLD could also release other GPI-anchored proteins important for hematopoiesis and other physiologic processes.  相似文献   
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OBJECTIVE: Congenital esophageal stenosis is thought to be a rare disease confined to infancy and childhood with only a few case reports in adults described. METHODS: We report five patients between the ages of 19 and 46 yr who presented with this disorder over a 2-yr period. RESULTS: Patients had been labeled with reflux strictures, webs, or as idiopathic in the past. All patients had chronic solid food dysphagia, some since early childhood. The location of the stricture varied, occurring in the mid or proximal esophagus in four, but throughout the esophagus in one. Radiographic and endoscopic appearance was a smooth concentric stricture or multiple rings, sometimes tracheal in appearance. Endosonography was performed in two patients, both of whom had focal circumferential hypoechoic wall thickening with disruption of the normal layer pattern corresponding to the areas of luminal narrowing. All patients dilated had good symptomatic response, with resolution of symptoms up to 6 months in follow-up. CONCLUSIONS: We suggest that congenital esophageal stenosis does occur in adults and may be underrecognized. Its endosonographic appearance is described.  相似文献   
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We recovered two isolates (EP1 and EP2) of Escherichia coli from the same patient that had identical pulsed-field gel electrophoresis patterns but required different MICs of ciprofloxacin (CIP): 16 and 256 mg/liter for EP1 and EP2, respectively. Both isolates had mutations in the quinolone resistance-determining regions of GyrA (Ser83Leu and Asp87Tyr) and ParC (Ser80Ile), but not in those regions of GyrB or ParE. Isolate EP2 was also more resistant to chloramphenicol, tetracyclines, cefuroxime, and organic solvents. A deletion of adenine (A) 1821 was found in marR of isolate EP2, which resulted in an 18-amino-acid C-terminal deletion in the MarR protein. The causative relationship between DeltaA1821 and the Mar phenotype was demonstrated both by the replacement of the wild-type marR by marR DeltaA1821 in isolate EP1 and by complementation with the wild-type marR in trans in isolate EP2. In isolate EP2 complemented with wild-type marR, susceptibility to chloramphenicol was restored completely, whereas susceptibility to CIP was restored only incompletely. Northern blotting demonstrated increased expression of marA and acrAB but not of soxS in isolate EP2 compared to EP1. In conclusion, the deletion of A1821 in marR in the clinical isolate EP2 caused an increase in the MICs of CIP and unrelated antibiotics. Presumably, the C-terminal part of MarR is necessary for proper repressor function.  相似文献   
57.
Metabolism of arachidonic acid (AA) via the cyclooxygenase pathway reduces glucose-stimulated insulin release. However, metabolism of AA by the lipoxygenase pathway and the consequent effects on insulin secretion have not been simultaneously assessed in the endocrine islet. Both dispersed endocrine cell-enriched pancreatic cells of the neonatal rat, as well as intact islets of the adult rat, metabolized [(3)H]AA not only to cyclooxygenase products (prostaglandins E(2), F(2alpha), and prostacyclin) but also to the lipoxygenase product 12-hydroxyeicosatetraenoic acid (12-HETE). 12-HETE was identified by coelution with authentic tritiated or unlabeled 12-HETE using four high performance liquid chromatographic systems under eight mobile-phase conditions and its identity was confirmed by gas chromatography/mass spectrometry using selected ion monitoring. The predominant effect of exogenous AA (5 mug/ml) was to stimulate insulin release from pancreatic cells grown in monolayer. This effect was concentration- and time-dependent, and reversible. The effect of AA upon insulin release was potentiated by a cyclooxygenase inhibitor (indomethacin) and was prevented by either of two lipoxygenase inhibitors (5,8,11,14-eicosatetraynoic acid [ETYA] and BW755c). In addition, glucose, as well as two structurally dissimilar agents (the calcium ionophore A23187 and bradykinin), which activate phospholipase(s) and thereby release endogenous AA in several cell systems, also stimulated insulin secretion. The effects of glucose, glucagon, bradykinin and high concentrations of A23187 (5 mug/ml) to augment insulin release were blocked or considerably reduced by lipoxygenase inhibitors. However, a lower concentration of the ionophore (0.25 mug/ml), which did not appear to activate phospholipase, was resistant to blockade. Exogenous 12-HETE (up to 2,000 ng/ml) did not alter glucose-induced insulin release. However, the labile intermediate 12-hydroperoxy-ETE increased insulin release. Furthermore, diethylmaleate (which binds intracellular glutathione and thereby impedes conversion of the lipoxygenase intermediates hydroperoxy-ETE and leukotriene A(4) to HETE and leukotriene C(4), respectively) potentiated the effect of glucose and of exogenous AA. Finally, 5,6-epoxy, 8,11,14-eicosatrienoic acid (a relatively stable epoxide analogue of leukotriene A(4)) as well as two other epoxy-analogues, potentiated glucose-induced insulin release. We conclude that dual pathways of AA metabolism exist in islet endocrine cells and have opposing regulatory effects on the beta cell-an inhibitory cyclooxygenase cascade and a stimulatory lipoxygenase cascade. Labile products of the latter pathway may play a pivotal role in stimulus-secretion coupling in the islet.  相似文献   
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BACKGROUND: Limited prior research suggests that depressed women are more likely to experience certain symptoms of depression than are depressed men. The purpose of this study was to examine whether such gender differences in depressive symptoms are present during adolescence. METHODS: The Childhood Version of the Schedule for Affective Disorders and Schizophrenia and the Beck Depression Inventory were administered to adolescents presenting for evaluation at an outpatient clinic (n=383; ages 11.9 to 20.0). RESULTS: Depressed girls and boys had similar symptom prevalence and severity ratings for most depressive symptoms. However, depressed girls had more guilt, body image dissatisfaction, self-blame, self-disappointment, feelings of failure, concentration problems, difficulty working, sadness/depressed mood, sleep problems, fatigue, and health worries than depressed boys on some comparisons. In contrast, depressed boys had higher clinician ratings of anhedonia, depressed morning mood, and morning fatigue. LIMITATIONS: Longitudinal research is needed to test whether such relatively gender-specific symptoms play different roles in the onset, maintenance, or remittance of depression for boys and girls. CONCLUSIONS: These findings indicate that, in general, the experience of depression is highly similar for adolescent girls and boys. However, some gender differences previously found among depressed adults appear to be present by adolescence, possibly suggesting somewhat distinct etiologies for depression among males and females.  相似文献   
60.
Cholesterol is known to be a major risk factor for coronary heartdisease (CHD). Current treatments for elevated blood cholesterolinclude dietary management, regular exercise, and drug therapywith fibrates, bile acid sequestrants, and statins. Suchtherapies, however, are often suboptimal and carry a risk forserious side effects. This study shows that microencapsulatedLactobacillus plantarum 80 (pCBH1) cells can efficientlybreak down and remove bile acids, and establishes a basis fortheir use in lowering blood serum cholesterol. Results show thatmicroencapsulated LP80 (pCBH1) is able to effectively break downthe conjugated bile acids glycodeoxycholic acid (GDCA) andtaurodeoxycholic acid (TDCA) with bile salt hydrolase (BSH)activities of 0.19 and 0.08μmol DCA/mg CDW/hrespectively. This article also summarizes the physiologicalinterrelationship between bile acids and cholesterol and predictsthe oral doses of microencapsulated Lactobacillusplantarum 80 (pCBH1) cells required for lowering cholesterol.  相似文献   
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