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1.
M. Diez L. Favaloro A. Bertolotti J. M. Burgos C. Vigliano M. P. Lastra M. J. Levin A. Arnedo C. Nagel A. G. Schijman R. R. Favaloro 《American journal of transplantation》2007,7(6):1633-1640
Heart transplantation (HTx) is a useful therapy for end‐stage Chaga? cardiomyopathy; however, Chagas reactivation remains a mayor complication. Parasitological methods offer poor diagnostic sensitivity, and use of more sensitive tools such as the Polymerase chain reaction (PCR) is usually necessary. In the present study, reactivation incidence and PCR usefulness for early reactivation diagnosis, as well as for treatment response evaluation during follow‐up, were analyzed using Strout parasite detection test, in 10 of 222 consecutive HTx patients suffering Chagas cardiomyopathy. PCR strategies targeted to minicircle sequences (kDNA, detection limit 1 parasite/ 10 mL blood) and miniexon genes (SL‐DNA, 200 parasite/10 mL) were performed to compare parasite burdens between samples. No patients received prophylactic antiprotozoal therapy (benznidazole). Five patients (50%) exhibited clinical reactivation within a mean period of 71.6 days; positive Strout results were observed in most cases presenting clinical manifestations. kDNA‐PCR was positive 38–85 days before reactivation, whereas SLDNA‐PCR became positive only 7–21 days later, revealing post‐HTx parasitic load enhancement present prior to clinical reactivation development. Reactivations were successfully treated with benznidazole and generated negative PCR results. Results observed in this study indicate the value of PCR testing for an early diagnosis of Chagas reactivation as well as for monitoring treatment efficacy. 相似文献
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Gopala K RANGAN Yiping WANG Yuet-Ching TAY Liguang CHEN David CH HARRIS 《Nephrology (Carlton, Vic.)》1998,4(1-2):57-64
SUMMARY: The effect of mild acute tubular injury on the progression of tubulointerstitial fibrosis was studied in pair-fed uninephrectomized male Wistar rats with established adriamycin nephrosis ( n = 34). Rats were stratified into three groups according to endogenous creatinine clearance (CrCl), proteinuria (Upr) and body weight (BW): (i) group 1 (Fe, n = 12) received a single intraperitoneal injection of ferric nitrilotriacetate (5 mg Fe/kg BW); (ii) group 2 (G, n = 10) three daily subcutaneous injections of gentamicin (60 mg/kg BW) and; (iii) group 3 (C, n = 12) saline injections. Serial CrCl (day 2, day 5, weeks 2, 4, 6 and 8) and renal histology (week 8) were examined following administration of nephrotoxin. CrCl was reduced on d2 (Fe: 0.78 ± 0.23 mL/min; mean ± SD) and day 5 (G: 0.91 ± 0.36 mL/min) as compared with C (1.22 ± 0.12 mL/min; P <0.05). There was no change in the serum creatinine and functional recovery occurred by d5 (Fe) and week 2 (G). Upr decreased transiently in G at week 2 (G: 482 ± 208 mg/day vs C: 716 ± 233; P = 0.05) despite similar food intake, baseline Upr and CrCl. At week 8, CrCl in Fe (0.84 ± 0.40 mL/min) was similar to C (0.84 ± 0.58 mL/min), whereas in G it remained stable (1.27 ± 0.39 mL/min; P <0.05). By morphometric analysis, mean relative interstitial volume (RIV) and glomerulosclerosis (GS) in Fe (RIV: 28.5 ± 13.4%; GS: 10.3 ± 12.3%) was no different to C (RIV: 24.5 ± 12.5%; GS: 20.9 ± 20.0%), whereas both parameters were reduced in G (RIV: 14.1 ± 8.1%; GS: 4.0 ± 4.8%; P <0.05). Mild gentamicin nephrotoxicity therefore reduced the progression of adriamycin nephrosis. the mechanism of this finding is unclear, but it may relate to altered glomerular and tubular cell handling of protein. 相似文献
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Different morphologic and density classes of sickle cells (SS) may play distinct roles in the generation of vasoocclusion, explaining the complexity of this phenomena. The densest SS red blood cells (RBCs) (SS4) can induce vasoocculsion in ex vivo microcirculatory preparations as well as in an intact animal model. Previous studies of the interaction of SS deformable discocytes with endothelial monolayers or the rat ex vivo mesocecum preparation have shown adhesion that is desmopressin (dDAVP)-stimulated, von Willebrand factor (vWF)-mediated, and limited to the small venules. However, in vivo adhesion of SS RBCs to the endothelium has neither been demonstrated nor characterized; and, in particular, the relation of adhesion to vasoocclusion is unknown. Using an intact animal model that involves injecting saline-washed, density-defined SS RBCs into the femoral artery of a rat, we find that: (1) Quantitative studies of RBCs retained in the rat thigh using 99mTc-labeled RBCs and gamma camera imaging showed that dDAVP induces a threefold increase in retention of normal (AA) cells and deformable SS discocytes (SS2). (2) electron microscopy and Microfil injection show that the retention of SS2 cells is due to adhesion to the vascular endothelium with no evidence of obstruction. (3) H-1 magnetic resonance imaging showed that retention of SS4 cells induced a dose-dependent increase in tissue edema (presumable secondary to tissue hypoxia), while retention of AA or SS2 cells produced no change. We conclude that endothelial adhesion of deformable SS discocytes can be demonstrated in an in vivo animal model, that this adhesion is enhanced by dDAVP (presumably related to, but not necessarily limited to the release of vWF), and that this phenomenon per se does not lead to vasoocclusion. Nevertheless, adhesion of deformable SS discocytes may have consequences. We hypothesize that adhesion of SS discocytes could narrow the lumen of postcapillary venules and facilitate secondary trapping of SS4 cells and lead to subsequent vasoocclusion. 相似文献
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无环鸟苷亲脂性前体药物脂质体的制备及体外抗病毒活性(英文) 总被引:2,自引:0,他引:2
本文通过将无环鸟苷(acyclovir,简称ACV)2’位羟基分别与月桂酰氯或棕榈酰氯进行酯化反应,制得亲脂性前体药物无环鸟苷月桂酸酯和无环鸟苷棕榈酸酯(分别简称为C12-ACV和C16-ACV),使脂质体包封率从ACV的29.9%提高到C12-ACV的95.6%和C16-ACV的97.1%;漏泄实验表明在4℃透析60h后,一半以上的ACV从脂质体中漏泄,而C12-ACV和C16-ACV的滞留率分别为70%和80%;体外抗疱疹病毒的试验中,在最低试验浓度0.044μmol/L时,ACV不显示抗病毒活性,而C16-ACV脂质体抑制细胞病变率达75%,说明前体药物通过与脂质体脂膜的结合增加了药物的进入细胞能力,从而提高了ACV的抗病毒能力。 相似文献
8.
E. Nagel J. Jähne K. Obermann J. Lotz A. Meyer zu Vilsendorf R. Pichlmayr 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1997,382(1):29-32
In this retrospective study of 24 patients who were treated at our clinic during the last 22 years after having attempted suicide, we evaluated aspects concerning abdominal-and transplantation surgery. There was a predominance of “hard” (70%) versus “soft” (30%) methods for suicide attempt. Intra-abdominal injuries resulting from attempted suicide by stabbing or shooting should lead to laparotomy— the prognosis is then good. Surgical treatment after intoxication, especially caustic ingestion, depends on endoscopic and clinical findings. The highly increased rates of suicide significantly by kidney transplantation. The risk of suicide after transplantation is further diminished with improved immunosuppressive treatment. Only in a few cases there is an indication for liver transplantation— in some cases of fulminant hepatic failure caused by self-administered paracetomol overdose. Auxiliary liver transplantation may then be considered. 相似文献
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Kundel HL; Gefter W; Aronchick J; Miller W Jr; Hatabu H; Whitfill CH; Miller W Sr 《Radiology》1997,205(3):859
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SUMMARY: Peritonitis and exit‐site infections remain the most important limitations to the delivery of continuous ambulatory peritoneal dialysis (CAPD). Contamination of the peritoneum, from endogenous or exogenous sources, is responsible for most peritonitis episodes. Patients usually present with a cloudy bag, although other causes should be distinguished. Clinical suspicion of peritonitis should be followed rapidly by microbiological examination and empirical treatment. Microbiological confirmation allows for subsequent treatment based on sensitivities. Other interventions such as catheter removal may be appropriate in some patients. Exit‐site infections should also be identified and treated early. Peritonitis may be further prevented by adequate exit‐site care, hygienic methods, and techniques to minimise early contamination of the exit site. Mupirocin may also have a role in preventing infections caused by Staphylococcus aureus. 相似文献