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41.
Alpha2-macroglobulin is a protease inhibitor that enhances procoagulant properties via the neutralization of plasmin, plasminogen activators and metalloproteinases. Additionally, alpha2-macroglobulin is thought to be involved in inflammatory reactions as a carrier protein for interleukin-6 (IL-6). The objective of this study was to evaluate the usefulness of alpha2-macroglobulin as a biomarker for cerebrovascular diseases. Patients with acute ischemic stroke (n = 159; 93 male and 66 female, 71.6 ± 10.3 years) and patients with no previous history of stroke (n = 77; 38 male and 39 female, 70.7 ± 9.5 years) were consecutively enrolled in this study. White matter lesions were assessed via the fluid-attenuated inversion recovery image of magnetic resonance images using the Fazekas classification. The serum alpha2-macroglobulin levels were measured by nephelometry. The serum alpha2-macroglobulin levels at admission in patients with acute ischemic stroke were higher than those in the control patients (230.2 ± 73.7 vs. 205.0 ± 55.8 mg/dl, p = 0.009). The serum alpha2-macroglobulin levels were positively correlated with age and the severity of the white matter lesions (R 2 = 0.048, p < 0.001 and R 2 = 0.058, p < 0.001, respectively), although there was no significant association between serum alpha2-macroglobulin levels and IL-6 levels. In addition, multivariate analysis showed that increased serum alpha2-macroglobulin levels were independently associated with the severity of white matter lesions [standardized partial regression coefficient (β) 0.102, p = 0.026]. Increased serum alpha2-macroglobulin levels might be involved in the pathophysiology of acute ischemic stroke. Furthermore, serum alpha2-macroglobulin levels, which were associated with high-grade white matter lesions, may reflect the chronic pathophysiological condition of cerebral small vessel disease.  相似文献   
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As a type of Ehlers-Danlos syndrome (EDS), vascular EDs (vEDS) is typified by a number of characteristic facial features (eg, large eyes, small chin, sunken cheeks, thin nose and lips, lobeless ears). However, vEDs does not typically display hypermobility of the large joints and skin hyperextensibility, which are features typical of the more common forms of EDS. Thus, colonic perforation or aneurysm rupture may be the first presentation of the disease. Because both complications are associated with a reduced life expectancy for individuals with this condition, an awareness of the clinical features of vEDS is important.Here, we describe the treatment of vEDS lacking the characteristic facial attributes in a 24-year-old healthy man who presented to the emergency room with abdominal pain. Enhanced computed tomography revealed diverticula and perforation in the sigmoid colon. The lesion of the sigmoid colon perforation was removed, and Hartmann procedure was performed. During the surgery, the control of bleeding was required because of vascular fragility. Subsequent molecular and genetic analysis was performed based on the suspected diagnosis of vEDS. These analyses revealed reduced type III collagen synthesis in cultured skin fibroblasts and identified a previously undocumented mutation in the gene for a1 type III collagen, confirming the diagnosis of vEDS. After eliciting a detailed medical profile, we learned his mother had a history of extensive bruising since childhood and idiopathic hematothorax. Both were prescribed oral celiprolol. One year after admission, the patient was free of recurrent perforation.This case illustrates an awareness of the clinical characteristics of vEDS and the family history is important because of the high mortality from this condition even in young people. Importantly, genetic assays could help in determining the surgical procedure and offer benefits to relatives since this condition is inherited in an autosomal dominant manner.  相似文献   
45.
We describe a patient with chronic myelogenous leukemia who developing severe intestinal bleeding after allogeneic peripheral blood stem cells transplantation (allo-PBSCT). PBSC were obtained from an HLA one-locus mismatch sibling donor. On day 26 after PBSCT, although there was no sign of graft-versus-host disease (GVHD) in either the skin or the liver, diarrhea and severe intestinal bleeding occurred. The histopathological examination of the colon revealed complete denudation of the epithelial cells of the mucosa and no obvious apoptosis. Neither red cell fragments nor hemorrhagic diathesis was seen during this episode and the patient was diagnosed as having GVHD. Methylpredonisolone followed by FK506 may be effective in controlling intestinal bleeding and was used in our patient. Acute GVHD involving only the intestine has rarely been described but when using HLA-mismatched PBSCs, acute GVHD may occur severely and atypically.  相似文献   
46.
We previously produced, in Escherichia coli, a human monoclonal antibody Fab fragment, CP33, specific for the galactose- and N-acetyl-D-galactosamine-inhibitable lectin of Entamoeba histolytica. To prepare antibodies with a higher affinity to the lectin, recombination PCR was used to exchange Ser91 and Arg96 in the third complementarity-determining region of the light chain with other amino acids. The screening of 200 clones of each exchange by an indirect fluorescent antibody test showed that 14 clones for Ser91 and nine clones for Arg96 reacted strongly with E. histolytica trophozoites. Sequence analyses revealed that the substituted amino acids at Ser91 were Ala in five clones, Gly in three clones, Pro in two clones, and Val in two clones, while the amino acid at position 96 was substituted with Leu in three clones. The remaining eight clones exhibited no amino acid change at position 91 or 96. These mutant Fab fragments were purified and subjected to a surface plasmon resonance assay to measure the affinity of these proteins to the cysteine-rich domain of lectin. Pro or Gly substitution for Ser91 caused an increased affinity of the Fab, but substitution with Ala or Val did not. The replacement of Arg96 with Leu did not affect affinity. These results demonstrate that modification of antibody genes by recombination PCR is a useful method for affinity maturation and that amino acid substitution at position 91 yields Fabs with increased affinity for the lectin.  相似文献   
47.
Interactions between monocytes/macrophages and endothelial cells play an important role in the pathogenesis of atherosclerosis, and the adherence of monocytes to the arterial endothelium is one of the early events in atherogenesis. In the present study, peritoneal macrophages harvested from green fluorescent protein (GFP) transgenic mice were used to analyze how Chlamydia pneumoniae infection affects the adherence of GFP-macrophages to mouse endothelial cells in vitro and to the aorta from normolipidemic and hyperlipidemic mice ex vivo. In vitro studies showed that C. pneumoniae-infected GFP-macrophages adhered better than uninfected macrophages to endothelial cells and GFP-macrophages adhered better to infected than uninfected endothelial cells. The ex vivo studies showed that C. pneumoniae-infected macrophages adhered better than uninfected macrophages to aortas from both normolipidemic and hyperlipidemic C57BL/6J mice and apolipoprotein E (ApoE)-deficient mice. In contrast, adherence of C. pneumoniae-infected macrophages to the aortas of intercellular adhesion molecule 1 (ICAM-1) knockout mice was not enhanced, suggesting that ICAM-1 is crucial for activation of the adherence of C. pneumoniae-infected macrophages to the endothelium. In conclusion, the present study defined a homing mechanism by which C. pneumoniae promotes the adherence of mononuclear phagocytes to the endothelium at the site of atherosclerotic lesion formation to promote the progression of atherosclerosis.  相似文献   
48.
In this study, we investigated the process of supernumerary upper incisor formation in the Pax6 mutant rat, rSey(2)/rSey(2), which exhibits a facial cleft between the medial nasal and maxillary processes. Histological investigation and epithelial labeling studies of wild type rat embryos indicated that the upper incisor develops by fusion of two primary dental placodes (PDPs) in the medial nasal process with a contribution from the epithelium of the maxillary process. In the rSey(2)/rSey(2) embryo, both PDPs are formed but they stay apart, then subsequently these PDPs independently develop into upper incisor tooth buds. In order to examine if the failure of the two placodes to fuse is due to the cleft between the maxillary and medial nasal processes, maxillary and medial nasal process fusion was inhibited with a barrier in wild type embryos. This resulted in the maintenance of the two distinct PDPs. These results demonstrate that fusion of the facial processes reduces the number of odontogenic placodes and is required to assemble all components at one site for rat upper incisor formation. The results also provide further insight into the mechanism of supernumerary incisor formation in human cleft lip conditions.  相似文献   
49.
In addition to hemochromatosis, aceruloplasminemia and ferroportin disease may be complicated by iron-induced multiple organ damage. Therefore, clinicopathological features should be evaluated in a wider range of genetic iron disorders. This study included 16 Japanese patients with genetic iron overload syndromes. The responsible genes were CP in four, HAMP in one, HJV in three, TFR2 in five, and SLC40A1 in three patients. No phenotype dissociation was observed in patients with the CP, TFR2, or HAMP genotypes. Two of the three patients with the HJV genotype displayed classic hemochromatosis instead of the juvenile type. Patients with the SLC40A1 genotype were affected by mild iron overload (ferroportin A) or severe iron overload (ferroportin B). Transferrin saturation was unusually low in aceruloplasminemia patients. All patients, except those with ferroportin disease, displayed low serum hepcidin-25 levels. Liver pathology showed phenotype-specific changes; isolated parenchymal iron loading in aceruloplasminemia, periportal fibrosis associated with heavy iron overload in both parenchymal and Kupffer cells of ferroportin B, and parenchyma-dominant iron-loading cirrhosis in hemochromatosis. In contrast, diabetes occurred in all phenotypes of aceruloplasminemia, hemochromatosis, and ferroportin disease B. In conclusion, clinicopathological features were partially characterized in Japanese patients with genetic iron overload syndromes.  相似文献   
50.

Purpose

The aim of this study was to compare the safety and short-term efficacy of transcatheter arterial chemoembolization (TACE) using cisplatin-Lipiodol suspension (CP/Lp) with that using epirubicin-Lipiodol emulsion (EP/Lp) in patients with recurrent hepatocellular carcinoma (HCC).

Materials and methods

A total of 28 HCC patients were enrolled prospectively and assigned to the CP/Lp group or EP/Lp group. Adverse effects related to TACE were graded; and the treatment effect (TE) on HCC nodules at 3 months and overall tumor response at 6 months were assessed as the endpoint.

Results

No significant difference was observed between the groups regarding the frequency of adverse effects of grade 3 or less. The TE rates for 100% necrosis plus >50% necrosis in 62 HCC nodules in the CP/Lp group and 75 HCC nodules in the EP/Lp group were 72.6% and 66.7%, respectively (P = 0.894). Overall tumor response revealed that six patients (50.0%) in the CP/Lp group and six patients (37.5%) in the EP/Lp group had a partial response plus a complete response, with no significant difference (P = 0.615). TACE-free control curves for both groups revealed no significant difference (P = 0.513).

Conclusion

No significant difference was found with regard to adverse effects, the treatment effect on HCC nodules, or overall tumor response between the CP/Lp and EP/Lp groups.  相似文献   
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