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41.

Background  

Most current guidelines recommend two serological tests to diagnose chronic Chagas disease. When serological tests are persistently inconclusive, some guidelines recommend molecular tests. The aim of this investigation was to review chronic Chagas disease diagnosis literature and to summarize results of ELISA and PCR performance.  相似文献   
42.
Proteinuria and increased renal reabsorption of NaCl characterize the nephrotic syndrome. Here, we show that protein-rich urine from nephrotic rats and from patients with nephrotic syndrome activate the epithelial sodium channel (ENaC) in cultured M-1 mouse collecting duct cells and in Xenopus laevis oocytes heterologously expressing ENaC. The activation depended on urinary serine protease activity. We identified plasmin as a urinary serine protease by matrix-assisted laser desorption/ionization time of-flight mass spectrometry. Purified plasmin activated ENaC currents, and inhibitors of plasmin abolished urinary protease activity and the ability to activate ENaC. In nephrotic syndrome, tubular urokinase-type plasminogen activator likely converts filtered plasminogen to plasmin. Consistent with this, the combined application of urokinase-type plasminogen activator and plasminogen stimulated amiloride-sensitive transepithelial sodium transport in M-1 cells and increased amiloride-sensitive whole-cell currents in Xenopus laevis oocytes heterologously expressing ENaC. Activation of ENaC by plasmin involved cleavage and release of an inhibitory peptide from the ENaC γ subunit ectodomain. These data suggest that a defective glomerular filtration barrier allows passage of proteolytic enzymes that have the ability to activate ENaC.Nephrotic syndrome is characterized by proteinuria, sodium retention, and edema. Increased renal sodium reabsorption occurs in the cortical collecting duct (CCD),1,2 where a rate-limiting step in transepithelial sodium transport is the epithelial sodium channel (ENaC), which is composed of the three homologous subunits: α, β, γ.3ENaC activity is regulated by hormones, such as aldosterone and vasopressin (AVP)4,5; however, adrenalectomized rats and AVP-deficient Brattleboro rats are capable of developing nephrotic syndrome,1,6 and nephrotic patients do not consistently display elevated levels of sodium-retaining hormones,7,8 suggesting that renal sodium hyper-reabsorption is independent of systemic factors. Consistent with this, sodium retention is confined to the proteinuric kidney in the unilateral puromycin aminonucleoside (PAN) nephrotic model.2,9,10There is evidence that proteases contribute to ENaC activation by cleaving the extracellular loops of the α- and γ-subunits.1113 Proteolytic activation of ENaC by extracellular proteases critically involves the cleavage of the γ subunit,1416 which probably leads to the release of a 43-residue inhibitory peptide from the ectodomain.17 Both cleaved and noncleaved channels are present in the plasma membrane,18,19 allowing proteases such as channel activating protease 1 (CAP1/prostasin),20 trypsin,20 chymotrypsin,21 and neutrophil elastase22 to activate noncleaved channels from the extracellular side.23,24 We hypothesized that the defective glomerular filtration barrier in nephrotic syndrome allows the filtration of ENaC-activating proteins into the tubular fluid, leading to stimulation of ENaC. The hypothesis was tested in the PAN nephrotic model in rats and with urine from patients with nephrotic syndrome.  相似文献   
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The distribution of glycine-like immunoreactivity on cat lumbar motoneurons was examined in electron microscopy, using pre-embedding immunocytochemistry. In the dorsolateral portion of the ventral horn, numerous labeled axon terminals were presynaptic to somatic and dendritic profiles of alpha-motoneurons. Most of the glycinergic boutons contained pleomorphic vesicles and showed symmetrical contacts. On the somatic and proximal dendritic compartments, glycinergic terminals accounted for, respectively, 24.6 and 26.6% of the total number of terminals. There were very few glycinergic terminals on gamma-motoneurons. Immunoreactive axons, dendrites and cell bodies were also observed near the motoneurons. These results support the view that glycine plays a major role in the inhibition of alpha-motoneurons and suggest that inhibitory mechanisms occur on the soma as well as on dendrites.  相似文献   
44.
BACKGROUND: Tinea pedis is a common dermatophyte infection with frequent recurrences. Terbinafine (presently used as a 1-week topical treatment of tinea pedis) is now available in a novel topical solution (film-forming solution--FFS), developed to allow single application. OBJECTIVES: To demonstrate the efficacy and safety of terbinafine 1% FFS in a randomized, double-blind, placebo-controlled, phase III trial, and to determine relapse or re-infection rate of tinea pedis at 12 weeks. PATIENTS/METHODS: Fifty-four centres (27 in France; 27 in Germany) enrolled 273 evaluable patients (2 : 1 randomization). Patients applied terbinafine 1% FFS or placebo only once between, under and over the toes, soles and sides of both feet. Efficacy assessments included direct microscopy, mycological culture, and clinical signs and symptoms at baseline, and at weeks 1, 6 and 12 after the single drug application. RESULTS: Effective treatment (negative mycology plus absent/minimal symptoms) at week 6 in the terbinafine 1% FFS group was 63%; vehicle was 17% (P相似文献   
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A Caulobacter sp. isolate was recovered from the dialysis fluid of a patient undergoing peritoneal dialysis. Bacterial identification included electron microscopy and 16S rDNA sequencing. To our knowledge, this is the first report of human Caulobacter infection. Special growth requirements suggest that Caulobacter spp. may be overlooked in the clinical microbiology laboratory.  相似文献   
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Inhibition of monocyte esterase activity by organophosphate insecticides   总被引:3,自引:0,他引:3  
Lee  MJ; Waters  HC d 《Blood》1977,50(5):947-951
Organophosphate insecticides, such as Vapona, Naled, and Rabon, are highly potent inhibitors of an enzyme found in human monocytes. The enzyme, a specific monocyte esterase, could be inhibited by Vapona in blood samples via airborne contamination at levels easily achieved from commercial slow-release insecticide strips. Fifty percent inhibition (I50)--as measured on the Hemalog D (Technicon Corp.)--occurred at solution concentrations of 0.22, 1.5, and 2.6 X 10(-6) g/liter for Vapona, Rabon, and Naled, respectively. Parathion (a thiophosphate) and Baygon (a carbamate) were less potent, with I50 values of 3.7 X 10(-5) and 1.5 X 10(-4) g/liter, respectively. Dursban (another thiophosphate) and Carbaryl (a carbamate) showed only marginal inhibition. Eserine, malathion, nicotine and pyrethrum had no inhibitory effect up to 0.5 g/liter. The occurrence of this effect in vivo has not yet been shown, nor is it clear what the implications of such an effect would be. The inhibition of this enzyme by airborne contaminants, however, may interfere with the proper functioning of the Hemalog D.  相似文献   
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