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51.
A 60-year-old man presented with ureteric obstruction secondary to a mycotic right common iliac artery aneurysm complicating
methicillin-resistant Staphylococcus aureus (MRSA) bacteremia. The diagnosis of MRSA was not known at the time of surgery, and in situ replacement of the aneurysm using
a rifampicin-bonded prosthesis was performed. The patient made a full recovery, and to date there is no evidence of residual
or recurrent infection. To our knowledge, this is the first reported case of mycotic iliac aneurysm infected with MRSA in
the literature. We discuss the consequences and the considerable diagnostic and therapeutic problems that arise.
Presented at the Fifty-third International Congress of the European Society for Cardiovascular Surgery, Ljubljana, Slovenia,
June 2-5, 2004. 相似文献
52.
53.
Hb Taradale [beta82(EF6)Lys-->Arg] was initially detected as a split Hb A0 peak on Hb A1c, monitoring. Red cell parameters, hemoglobin (Hb) electrophoresis and stability tests were normal. Mass spectrometry (ms) clearly identified a variant beta chain with a mass increase of 28 Da and peptide mapping located the mutation site to peptide betaT-9. DNA sequencing confirmed the presence of a novel beta82(EF6)Lys-->Arg mutation. This conservative substitution at a 2,3-diphosphoglycerate (2,3-DPG) binding site did not, however, appear to affect the P50 for oxygen binding. 相似文献
54.
Jung CK Chung S Lee YY Hwang SH Kang CS Lee KY 《Aviation, space, and environmental medicine》2005,76(8):720-725
INTRODUCTION: [corrected] Hind-limb unloading (HU) in rodents has been used as a model to simulate some effects of spaceflight on the musculoskeletal, cardiovascular, and immune systems in humans. HU leads to redistribution of extracellular fluid to the upper half of the body. We hypothesized that altered blood flow might induce intercellular adhesion molecule-1 (ICAM-1) expression of arterial endothelial cells and increase monocyte-endothelial adhesion. METHODS: Male Sprague-Dawley rats were randomly assigned to either a control, 7-d HU, or 28-d HU group. The expression of ICAM-1 and monocyte adhesion was determined by immunohistochemistry. RESULTS: In control rats, ICAM-1 was not expressed in all vessels studied. HU induced the ICAM-1 expression in the carotid artery and thoracic aorta, but did not in the femoral artery. Staining density of ICAM-1 expression was stronger in the 28-d HU group than in the 7-d HU group. Endothelial-monocyte adhesion was significantly increased in the carotid artery and thoracic aorta from the HU groups compared with the control group, but completely absent in the femoral arteries of both the HU and control groups. In the thoracic aorta, but not in the carotid artery, endothelial-monocyte adhesion was more increased after 28-d HU than after 7-d HU. CONCLUSION: These data indicate that an increase in shear stress induced by HU stimulates ICAM-1 expression on arteries, which contributes to adhesion of monocytes on their endothelium. Reduced shear stress has no effects on monocyte adhesion. 相似文献
55.
Diallyl trisulfide modulates cell viability and the antioxidation and detoxification systems of rat primary hepatocytes 总被引:4,自引:0,他引:4
This study investigated the effects of various concentrations of diallyl trisulfide (DATS) and incubation times on cell viability, glutathione (GSH) content, and GSH-related enzyme activity in rat primary hepatocytes. Isolated and cultured primary rat hepatocytes were used as an experimental model. Cells were treated with 0 (control), 0.025, 0.05, or 0.25 mmol/L DATS for 0, 4, 8, or 24 h. After 24 h of treatment, some cells were incubated in fresh medium without DATS for an additional 24 h (48-h incubations). Based on lactate dehydrogenase (LDH) leakage and morphological examination, hepatocytes treated with 0.025 mmol/L DATS did not differ from the control cells at 4, 8, 24, and 48 h of incubation. However, LDH leakage was higher than in the control cells (P < 0.05) when the hepatocytes were treated with 0.05 or 0.25 mmol/L DATS for 4 h or more. The intracellular GSH levels of hepatocytes treated with 0.025 or 0.05 mmol/L DATS were higher than those of the control cells (P < 0.05), whereas those treated with 0.25 mmol/L DATS did not differ. The activity of glutathione reductase (GRd) was higher than in the control cells at 24 h (P < 0.05) when the hepatocytes were treated with 0.025 mmol/L DATS. When the hepatocytes were treated with 0.025 mmol/L DATS, the activity of glutathione S-transferase (GST) was higher than in the control cells at 48 h (P < 0.05). In hepatocytes treated with 0.05 mmol/L DATS, the activity of GST and glutathione peroxidase (GPx) was higher than in the control cells (P < 0.05) at 24 and 48 h of incubation. The results indicate that 0.025 or 0.05 mmol/L DATS could enhance antioxidation and detoxification capabilities by increasing the intracellular GSH level and the activity of GPx, GRd, or GST in rat primary hepatocytes. However, 0.05 or 0.25 mmol/L DATS might adversely affect the viability of hepatocytes. 相似文献
56.
Two new paracetamol/dioxane solvates--a system exhibiting a reversible solid-state phase transformation 总被引:1,自引:0,他引:1
Vrcelj RM Clark NI Kennedy AR Sheen DB Shepherd EE Sherwood JN 《Journal of pharmaceutical sciences》2003,92(10):2069-2073
This work reports on the crystal structures of two dioxane solvates of paracetamol that are true polymorphs. The high temperature phase is an orthorhombic form, space group Pbca, Z = 8, a = 12.6078(3) A, b = 12.1129(2) A, c = 13.4138(3) A, V = 2048.52(7) A(3), (at 295 K) and the low temperature form is monoclinic, space group P21/c, Z = 4, a = 12.325(6) A, b = 11.965(4) A, c = 13.384(6) A, beta = 92.01 degrees, V = 1972.6(14)A(3) (at 123 K). The structures of these polymorphs are described as is the interrelationship between the two structures. In addition to the structural interrelationship, it is shown that the two forms undergo a reversible phase transformation. Desolvation of either form generates the stable monoclinic phase of paracetamol. 相似文献
57.
Developmental genetic malformations of the cerebral cortex 总被引:3,自引:0,他引:3
Cortical malformations give rise to severe clinical manifestations such as epilepsy and mental retardation, but sometimes
to more subtle problems like dyslexia. From a clinical standpoint, such structural abnormalities are diagnosed by radiographic
and histologic findings, with disease classifications often based on these observations. Using this categorization, many of
the responsible genes have been determined and now provide a means of understanding the molecular basis of the neurologic
disorders. This review discusses the known genetic developmental syndromes in the context of the observed cortical malformations,
the expression and function of the responsible genes, and their potential roles during the various stages of central nervous
system development. 相似文献
58.
Effects of c-Myc overexpression on the DNA damage-induced G2/M checkpoint were studied in finite lifespan, normal human mammary epithelial cells (HMECs). Previously, we showed that c-Myc attenuates G1/S arrest and leads to an inappropriate entry of cells with damaged DNA into the S phase, following treatment with ionising radiation (IR). Here we show that, in striking contrast to control cells, c-Myc-overexpressing HMECs demonstrate a significant attenuation of the G2/M arrest, following IR, and enter into inappropriate mitoses. At the molecular level, ectopic overexpression of c-Myc leads to an unusually high level of expression of cyclin B1, and the elevated levels of cyclin B1 were maintained, after gamma-irradiation. Introduction of DNA damage in c-Myc-overexpressing, normal mammary epithelial cells eventually induces apoptosis, indicating a dramatic sensitisation by c-Myc of DNA damage-induced apoptosis. These two remarkable phenotypes, checkpoint attenuation and sensitisation to apoptosis, resulting from a deregulation of the protooncogene c-myc, may produce a unique pattern of alternating cycles, consisting first of amplification of DNA damage, followed by apoptosis-assisted selective pressure. The result of this alternating pattern of damage apoptosis could facilitate the selection of certain genomic alterations required for cellular survival and cellular transformation. 相似文献
59.
Despite improvements in treatment, the 5-year survival for metastatic colorectal cancer remains poor. Novel approaches such as gene immunotherapy are being investigated to improve treatment. Retroviral gene transfer methods have been shown to transduce primary human T lymphocytes effectively resulting in the expression of therapeutic genes. However, a number of defects have been identified in T lymphocytes isolated from patients bearing tumour, which may have critical implications for the development of gene-targeted T cells as an anticancer therapy. To address this issue, primary T lymphocytes were isolated from patients with advanced colorectal cancer and tested for their ability to be transduced and to express subsequently a chimeric immune receptor consisting of a single-chain antibody fragment antigen-binding moiety specific for carcinoembryonic antigen (CEA) fused to the T cell receptor (TCR) CD3zeta chain. In 10 out of 10 patients, T lymphocytes were transduced, expanded in the absence of selection and tested for functional activity against CEA-expressing tumour cells. In each case, functional-specific cytotoxic activity was observed. Negligible activity was found in control cultures. This study highlights the feasibility of patient-derived T lymphocytes as a source of immune cells for autologous gene immunotherapy approaches. 相似文献
60.
We present the case of a female patient in whom acute overt hepatitis developed after 60 days of ketoconazole administration (200 mg/day). A prompt renewed hepatic injury 48 hours after an unintentional rechallenge 30 months later provided definitive evidence for a causative relationship between ketoconazole and acute liver injury. Histological examination revealed acute hepatitis with bridging hepatic necrosis. Clinicians should be aware of this cause and effect relationship between ketoconazole and acute liver injury, which can result in prompt severe acute liver injury after rechallenge. 相似文献