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1.
Serum LH, FSH and testosterone were quantitated in 9 patients with pure motor stroke within 24-48 h of its reported onset. High circulating LH with normal or low testosterone was noted in 8 of them. In response to an intravenous bolus of GnRH, the LH responses were exaggerated in all, but the FSH responses in 7 of them were comparable to those in eugonadal age matched controls. The rise in testosterone following 2000U hCG daily for 3 consecutive days was insignificant in the patients group compared to the controls. The data suggest normally operative pituitary testicular feed-back but decreased Leydig cell response in pure motor stroke. 相似文献
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3.
Immune reactions associated with silicone-based ventriculo-peritoneal shunt malfunctions in children
VandeVord PJ Gupta N Wilson RB Vinuya RZ Schaefer CJ Canady AI Wooley PH 《Biomaterials》2004,25(17):3853-3860
The implantation of ventriculo-peritoneal (VP) shunting systems is the most commonly performed neurological procedure in children with hydrocephalus. Although the overall complication risk is low, the cumulative risk of shunt failure is high and unfortunately results in a high prevalence of revision surgeries. In this study, we explored the concept that some pediatric patients may develop an immune response to either the proteins attached to the silicone implant surface or to the biomaterial itself, and that this reaction may contribute to VP shunt failure in some individuals. The data displays that the sterile shunt malfunction group had a higher rate of protein deposition and increased levels of autoantibodies to the extracted surface proteins as compared to individuals with functioning shunting systems. The precise nature of the shunt-bound proteins that serve as antigens in this experiment have not yet been determined. The data also indicated that some individuals develop antibodies to polymeric substances that cross-react with partially polymerized acrylamide. The detection of significant amounts of shunt-bound protein, antibody responses to these proteins and to polymeric substances suggest that an immunological response to these proteins may play a role in the mechanism behind sterile shunt malfunctions. 相似文献
4.
Helicobacter hepaticus hydrogenase mutants are deficient in hydrogen-supported amino acid uptake and in causing liver lesions in A/J mice 总被引:1,自引:0,他引:1 下载免费PDF全文
Helicobacter hepaticus, a causative agent of chronic hepatitis and hepatocellular carcinoma in mice, expresses a nickel-containing hydrogen-oxidizing hydrogenase enzyme. Growth of a hyaB gene-targeted mutant was unaffected by the presence of hydrogen, unlike the wild-type strain, which showed an enhanced growth rate when supplied with H(2). Hydrogenase activities in H. hepaticus were constitutive and not dependent on the inclusion of H(2) during growth. Addition of nickel during growth significantly stimulated both urease (for wild-type and hyaB) and hydrogenase (for wild-type) activities. In a 5-h period, the extent of (14)C-labeled amino acid uptake by the wild type was markedly enhanced in the presence of hydrogen and was >5-fold greater than that of the hyaB mutant strain. In the presence of H(2), the short-term whole-cell amino acid uptake V(max) of the parent strain was about 2.2-fold greater than for the mutant, but the half-saturation affinity for amino acid transport was the same for the parent and mutant strain. The liver- and cecum-colonizing abilities of the strains was estimated by real-time PCR quantitation of the H. hepaticus-specific cytolethal distending toxin gene and showed similar animal colonization for the hyaB mutant and the wild type. However, at 21 weeks postinoculation, the livers from mice inoculated with wild type exhibited moderate lobular lymphoplasmacytic hepatitis with hepatocytic coagulative necrosis, but the hydrogenase mutants exhibited no histological evidence of lobular inflammation or necrosis. 相似文献
5.
Evaluation of a new commercially available immunoglobulin M and immunoglobulin G immunochromatographic test for diagnosis of melioidosis infection 总被引:5,自引:0,他引:5 下载免费PDF全文
Cuzzubbo AJ Chenthamarakshan V Vadivelu J Puthucheary SD Rowland D Devine PL 《Journal of clinical microbiology》2000,38(4):1670-1671
An immunochromatographic test for the rapid determination of immunoglobulin M (IgM) and IgG antibodies to Burkholderia pseudomallei was evaluated by using sera from bacteriologically confirmed melioidosis patients and high-risk and clinically suspected patients, along with disease control groups. The sensitivities were 100 and 93% for the IgG and IgM tests, respectively, while the specificity was 95% for both assays. The test was rapid and simple to perform, with results obtained in 10 min. 相似文献
6.
Helicobacter pylori possesses a membrane-bound, nickel containing, hydrogen uptake hydrogenase enzyme; its synthesis requires structural as well as accessory proteins, the latter needed for the complete maturation of the enzyme. Our lab previously characterized mutants in the accessory hyp genes, hypA, hypB, hypD and hypF that were all severely affected for hydrogenase activity, and in some cases (hypA and hypB mutants) also affected for urease activity. This finding prompted us to disrupt the two remaining unstudied hyp genes of H. pylori, hypC and hypE, in order to see if the same pleiotropic effect would be observed. In both mutants hydrogenase activity was abolished but urease activity remained unaffected. Addition of 5 microM nickel into the growth medium partially restored the hydrogenase activity in the hypE mutant and to a lesser extent in the hypC mutant. In addition, we also disrupted the genes HP0634 (referred as hydD in the H. pylori 26695 genome database) and HP0635 (whose function was unknown, referred to here as hydE) to address their possible roles in the hydrogenase synthesis/maturation process. In both cases, hydrogenase activities were abolished and addition of nickel could not restore the activity, suggesting that these proteins are involved in the hydrogenase synthesis process rather than in nickel mobilization/insertion steps. 相似文献
7.
Aier M Zadeng T Basu D Biswal N Nalini P 《Indian journal of pathology & microbiology》2002,45(3):355-357
A 17 days old male infant, who had features of Down Syndrome, presented with fever, refusal to feed and seizures. He had papular, crusted skin lesions, moderate hepatosplenomegaly and a rapid downhill course. Peripheral blood and bone marrow aspirate showed features of acute leukaemia. Congenital Leukaemia is a rare malignancy associated with a very poor prognosis. Paradoxically, many cases of Congenital Leukaemia, especially in infants with Down Syndrome, show spontaneous remission. 相似文献
8.
Jasminder Sahi Ralph H Stern Mark A Milad Kelly A Rose Gordon Gibson Xianxian Zheng Linda Stilgenbauer Nalini Sadagopan Summer Jolley Darryl Gilbert Edward L LeCluyse 《Drug metabolism and disposition》2004,32(12):1370-1376
Avasimibe, an acyl-CoA:cholesterol acyltransferase inhibitor, has been previously shown to be a potent inducer of CYP3A4 and multiple drug resistance protein 1. We have further characterized the drug interaction potential of avasimibe by studying the inductive and inhibitory effect of this compound on major drug-metabolizing enzymes. Enzymes known to be involved in the metabolism of drugs likely to be coadministered with avasimibe, such as CYP1A1/2, CYP2C, and CYP2B6, were evaluated further by microarray analysis, Western immunoblotting, and activity assays, using rifampicin and beta-naphthoflavone as positive controls. No change was observed in CYP1A1/2 mRNA or activity levels after avasimibe treatment. Differential induction of CYP2C9- and CYP2B6-immunoreactive protein and activity was observed depending on drug concentration and donor. Microarray analysis showed a similar increase in CYP2C and CYP2B6 mRNA levels. The inhibition potential of avasimibe on the major drug-metabolizing enzymes was assessed using pooled human liver microsomes. Avasimibe inhibited CYP2C9 (IC50 2.9 microM), CYP1A2 (IC50 13.9 microM), and CYP2C19 (IC50 26.5 microM). A clinical drug interaction study was conducted to determine whether avasimibe might interact with the CYP2C9 substrate warfarin. Volunteers received 750 mg of avasimibe and showed a 54.2% reduction in trough concentrations of S-warfarin and decreased prothrombin times by 12, 15, 19, and 21% on days 6 through 9, respectively. These results demonstrate that avasimibe's inductive spectrum resembles that of rifampin. 相似文献
9.
Yellow hyaline membrane disease (YMH) of the neonate may be diagnosed clinically by tracheal aspiration cytology, an easily accessible, noninvasive, and safe technique. Since the frequent association of yellow membranes and kernicterus in premature infants at relatively low levels of serum bilirubin is significant, this means of diagnosis during life may be useful in identifying infants at risk for kernicterus. We also suggest use of this technique in evaluating the role of possible factors in the pathophysiology of yellow hyaline membranes. 相似文献
10.
A 28-year-old, healthy male presented with blurring of vision in the right eye following third dose of the AstraZeneca/COVISHIELD vaccine. Further examination revealed ischemic central retinal vein occlusion, and subsequent laboratory investigations were inconclusive for his eye disease. He responded to pulse corticosteroid and tapering doses of oral corticosteroids without requiring any intra-vitreal injection. Twelve articles were identified with the help of a PubMed literature search, and a short review of these patients was performed. Retinal vein occlusion can occur because of inflammation-induced thrombosis after coronavirus disease 2019 vaccination and may respond to anti-inflammatory therapy. 相似文献