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891.
Presence of air in the kidney can be problematic as the location of the air in different parts of the kidney greatly affects the subsequent management and outcome of the patient. We present here a case of a patient who had emphysematous pyelitis, in which CT scan was able to display presence of air only in the collecting system, thus differentiating this condition from the more fulminant emphysematous pyelonephritis. This leads to a more favourable prognosis and outcome to the patient. 相似文献
892.
Is HIV infection a TNF receptor signalling-driven disease? 总被引:1,自引:0,他引:1
Recent studies indicate that TNF (tumor necrosis factor) receptor signalling is a key player in HIV infection. HIV proteins have been shown to target TNF receptor signalling, leading both to apoptosis of uninfected bystander T cells and to sustained viral replication in infected T cells and macrophages. This article proposes a model that highlights the role of HIV proteins in the modulation of TNF receptor signalling and could explain both immune suppression and the formation of viral reservoirs during HIV infection. 相似文献
893.
894.
Well-differentiated neuroendocrine tumors (WDNT, carcinoid tumors) are uncommon indolent neoplasms. The genetic alterations of these tumors are not well characterized. We used genome-wide high-density single nucleotide polymorphism (SNP) array analysis to detect copy number alterations in 29 WDNTs, including seven lung, seven nonileal gastrointestinal, and 15 ileal tumors, and compared with allelic imbalances in 15 pancreatic endocrine tumors (PETs). Most frequent allelic imbalances in WDNTs were losses of chromosome 18 in 10 tumors (34%), chromosome 21 or 21q in six (21%), chromosome 13 or 13q in five (17%) and chromosome 16 or 16q in four (14%) tumors, and amplification of chromosome 20 or 20p in seven (24%) tumors. We also found one tumor with loss of heterozygosity of chromosomes 10 and 15 without copy number loss. These allelic imbalances were associated with primary site of tumor: loss of chromosome 18 was present exclusively in ileal WDNTs (P = 0.001), and loss of chromosome 21 or 21q was more frequent in nonileal gastrointestinal WDNTs (P = 0.02). The tumors with loss of chromosome 21 were larger compared to tumors without loss (P = 0.03). Chromosomal aberrations were less common in WDNTs from lung and gastrointestinal tract compared to PETs (P = 0.001). Our study shows that genome-wide allelotyping using SNP array is a powerful new tool for the analysis of allelic imbalances in WDNTs, and some of these alterations are tumor site-dependent and are different than in PETs. 相似文献
895.
ObjectivesTo evaluate gamma-glutamyltransferase (GGT), alanine transaminases (ALT) and aspartate transaminases (AST) levels and prevalent gestational diabetes mellitus (GDM).Design and methodsRandom plasma glucose, GGT, ALT and AST and the 50-g glucose challenge test were done on antenatal women followed by diagnostic 3-point 75-g oral glucose tolerance test within two weeks. GDM was diagnosed by ADA (2011) criteria.ResultsThe GDM rate was 12.2% (319/2610). Mean GGT level was higher in GDM women, 18 ± 12 vs. 16 ± 11 IU/L; P = 0.03. The risk for GDM was higher for women in the highest GGT quartile band compared to the lowest: RR 1.35 95%CI 1.0–1.8; P = 0.04. However, after adjustment for confounders, GGT was no longer associated with GDM. There was no correlation between ALT and AST levels and GDM.ConclusionsLiver transaminases do not predict GDM in contrast to type 2 diabetes. 相似文献
896.
Supan C Mombo-Ngoma G Dal-Bianco MP Ospina Salazar CL Issifou S Mazuir F Filali-Ansary A Biot C Ter-Minassian D Ramharter M Kremsner PG Lell B 《Antimicrobial agents and chemotherapy》2012,56(6):3165-3173
Ferroquine (SSR97193), a ferrocene-quinoline conjugate, is a promising novel antimalarial currently undergoing clinical evaluation. This study characterizes its pharmacokinetic properties. Young male African volunteers with asymptomatic Plasmodium falciparum infection were administered a single oral dose (n = 40) or a repeated oral dose (n = 26) given over 3 days of ferroquine in two dose-escalation, double-blind, randomized, placebo-controlled clinical trials. In addition, a food interaction study was performed in a subsample of participants (n = 16). The studies were carried out in Lambaréné, Gabon. After single-dose administration of ferroquine, dose linearity was demonstrated in a dose range of 400 to 1,200 mg for maximum mean blood concentrations ([C(max)] 82 to 270 ng/ml) and in a dose range of 400 to 1,600 mg for overall exposure to ferroquine (area under the concentration-time curve [AUC], 13,100 to 49,200 ng · h/ml). Overall mean estimate for blood apparent terminal half-life of ferroquine was 16 days and 31 days for its active and major metabolite desmethylferroquine (SSR97213). In the 3-day repeated-dose study, C(max) and overall cumulated exposure to ferroquine (AUC(cum)) increased in proportion with the dose from day 1 to day 3 between 400 and 800 mg. No major food effect on ferroquine pharmacokinetics was observed after single administration of 100 mg of ferroquine except for a slight delay of time to maximum blood concentration (t(max)) by approximately 3 h. The pharmacokinetics of ferroquine and its active main metabolite are characterized by sustained levels in blood, and the properties of ferroquine as a partner drug in antimalarial combination therapy should be evaluated. 相似文献
897.
Rahmani-Neishaboor E Hartwell R Jalili R Jackson J Brown E Ghahary A 《Acta biomaterialia》2012,8(10):3660-3668
Localized controlled release of anti-fibrogenic factors can potentially prevent tissue fibrosis surrounding biomedical prostheses, such as vascular stents and breast implants. We have previously demonstrated that therapeutic intervention with topically applied stratifin in a rabbit ear fibrotic model not only prevents dermal fibrosis but also promotes more normal tissue repair by regulating extracellular matrix deposition. In this work, the anti-fibrogenic effect of a controlled release form of stratifin was investigated in the prevention of fibrosis induced by dermal poly(lactic-co-glycolic acid) (PLGA) microsphere/poly(vinyl alcohol) (PVA) hydrogel implants. Pharmacodynamic effects were evaluated by histopathological examination of subcutaneous tissue surrounding implanted composites. Controlled release of stratifin from PLGA microsphere/PVA hydrogel implants significantly moderated dermal fibrosis and inflammation by reducing collagen deposition (30%), total tissue cellularity (48%) and infiltrated CD3(+) immune cells (81%) in the surrounding tissue compared with the stratifin-free implants. The controlled release of stratifin from implants markedly increased the level of matrix metalloproteinase-1 expression in the surrounding tissue, which resulted in less collagen deposition. These stratifin-eluting PLGA/PVA composites show promise as coatings to decrease the typical fibrosis exhibited around implanted biomedical prostheses, such as breast implants and vascular stents. 相似文献
898.
Belfield EJ Gan X Mithani A Brown C Jiang C Franklin K Alvey E Wibowo A Jung M Bailey K Kalwani S Ragoussis J Mott R Harberd NP 《Genome research》2012,22(7):1306-1315
Ionizing radiation has long been known to induce heritable mutagenic change in DNA sequence. However, the genome-wide effect of radiation is not well understood. Here we report the molecular properties and frequency of mutations in phenotypically selected mutant lines isolated following exposure of the genetic model flowering plant Arabidopsis thaliana to fast neutrons (FNs). Previous studies suggested that FNs predominantly induce deletions longer than a kilobase in A. thaliana. However, we found a higher frequency of single base substitution than deletion mutations. While the overall frequency and molecular spectrum of fast-neutron (FN)-induced single base substitutions differed substantially from those of "background" mutations arising spontaneously in laboratory-grown plants, G:C>A:T transitions were favored in both. We found that FN-induced G:C>A:T transitions were concentrated at pyrimidine dinucleotide sites, suggesting that FNs promote the formation of mutational covalent linkages between adjacent pyrimidine residues. In addition, we found that FNs induced more single base than large deletions, and that these single base deletions were possibly caused by replication slippage. Our observations provide an initial picture of the genome-wide molecular profile of mutations induced in A. thaliana by FN irradiation and are particularly informative of the nature and extent of genome-wide mutation in lines selected on the basis of mutant phenotypes from FN-mutagenized A. thaliana populations. 相似文献
899.
Pallister-Hall syndrome (PHS) is a pleiotropic autosomal-dominant malformation syndrome rarely presenting with genitourinary malformations. Literature has recorded 14 cases of PHS with genitourinary findings out of which only six have been females presenting with hydrometrocolpos and/or vaginal atresia. Fetal autopsy findings on a 39 weeks' gestation including demonstration of corticotroph deficiency in the pituitary, along with the review of literature is being presented here. None of the earlier literature pertaining to PHS with hydrometrocolpos and/or vaginal atresia describes an intrauterine fetal demise due to corticotroph deficiency. 相似文献
900.
H. M. Fritsche A. Aziz F. Eder W. Otto S. Denzinger W. F. Wieland M. May F. Hofst?dter A. Hartmann M. Burger 《Virchows Archiv : an international journal of pathology》2012,461(6):655-661
Incidental prostate cancer is often found in cystoprostatectomy specimens. The presence of a clinically significant tumour has an impact on follow-up strategies. In prostatectomy specimen for prostate cancer, whole-mount sections improve diagnostic accuracy. The present study compares detection of incidental prostate cancer in complete to routine processing. We included 295 consecutive patients who underwent radical cystoprostatectomy. Between 01/1995 and 12/2003 (period I), specimens of 129 patients were partially processed, whereas between 01/2004 and 03/2009 (period II), specimens of 166 patients were completely processed. Incidental prostate cancer was detected overall in 91 (30.8?%) patients. Prostate cancer was detected in 24 (18.6?%) patients in period 1 and in 67 (40.4?%) patients in period 2 (p?<?0.001). Potentially clinically significant prostate cancer was detected in 12 (9.2?%) and 29 (17.5?%) patients, respectively (p?=?0.044). Complete embedding and processing of cystoprostatectomy specimen yield significantly more potentially clinically relevant prostate cancers. The present data suggest that notably in younger men the specimens should be completely processed. 相似文献