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901.
The aim of this work was to assess the prevalence of a genetic predisposition to disseminated intravascular coagulation (DIC) among acutely poisoned patients. Activated protein C resistence (APCR) is a genetically determined cause of thrombophilia and DIC development. One hundred seventy-six subjects were divided into three groups: one consisted of 83 acutely poisoned patients with DIC; a second consisted of 57 acutely poisoned patients without DIC; the third group consisted of 91 healthy controls. Abnormal results of APCR testing were found in 24.1% of the poisoned DIC group, 5.3% of the poisoned nonDIC group, and 3.3% of the control group. Genetic tests were performed in 37 selected patients. Factor V Leiden mutation (G/A genotype) was determined to be present in people whose R index value was below 1.9. These results raise the possibility that outcomes of acute poisonings may be influenced by genetic predisposition.  相似文献   
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903.

Background

The 22q11.2 microdeletion syndrome (22q11.2 deletion syndrome -22q11.2DS) refers to congenital abnormalities, including primarily heart defects and facial dysmorphy, thymic hypoplasia, cleft palate and hypocalcaemia. Microdeletion within chromosomal region 22q11.2 constitutes the molecular basis of this syndrome. The 22q11.2 microdeletion syndrome occurs in 1/4000 births. The aim of this study was to determine the frequency of 22q11.2 microdeletion in 87 children suffering from a congenital heart defect (conotruncal or non-conotruncal) coexisting with at least one additional 22q11.2DS feature and to carry out 22q11.2 microdeletion testing of the deleted children's parents. We also attempted to identify the most frequent heart defects in both groups and phenotypic traits of patients with microdeletion to determine selection criteria for at risk patients.

Methods

The analysis of microdeletions was conducted using fluorescence in situ hybridization (FISH) on metaphase chromosomes and interphase nuclei isolated from venous peripheral blood cultures. A molecular probe (Tuple) specific to the HIRA (TUPLE1, DGCR1) region at 22q11 was used for the hybridisation.

Results

Microdeletions of 22q11.2 region were detected in 13 children with a congenital heart defect (14.94% of the examined group). Microdeletion of 22q11.2 occurred in 20% and 11.54% of the conotruncal and non-conotruncal groups respectively. Tetralogy of Fallot was the most frequent heart defect in the first group of children with 22q11.2 microdeletion, while ventricular septal defect and atrial septal defect/ventricular septal defect were most frequent in the second group. The microdeletion was also detected in one of the parents of the deleted child (6.25%) without congenital heart defect, but with slight dysmorphism. In the remaining children, 22q11.2 microdeletion originated de novo.

Conclusions

Patients with 22q11.2DS exhibit wide spectrum of phenotypic characteristics, ranging from discreet to quite strong. The deletion was inherited by one child. Our study suggests that screening for 22q11.2 microdeletion should be performed in children with conotruncal and non-conotruncal heart defects and with at least one typical feature of 22q11.2DS as well as in the deleted children's parents.  相似文献   
904.

BACKGROUND:

Epidermal growth factor receptor (EGFR) is involved in the progression of many cancer types and represents an important therapeutic target.

METHODS:

To determine the role of EGFR in renal cell carcinoma (RCC), the authors analyzed 1088 tumors in a tissue microarray format by using immunohistochemistry and fluorescence in situ hybridization (FISH). A subset of 63 cancers was sequenced for EGFR exon 18 through 21 mutations.

RESULTS:

EGFR expression was observed in 83.8% of clear cell carcinomas, in 68.2% of papillary carcinomas, in 75% of chromophobe carcinomas, and in 50% of oncocytomas. Within clear cell carcinomas, the expression level of EGFR was associated with high tumor grade (P < .0001), advanced pathologic tumor classification (P < .0001), and, to a lesser extent, lymph node status (P = .0326). FISH analysis revealed increased EGFR copy numbers (high polysomy) in 5.5% of tumors and amplification in 0.1% of tumors. EGFR copy number increases were associated with EGFR protein expression (P = .0015). Within clear cell carcinomas, EGFR copy number increases were associated with high tumor grade (P < .0001), advanced pathologic tumor classification (P = .0472), and lymph node status (P = .0065). No exon 18 through 21 mutations were identified in 63 sequenced tumors.

CONCLUSIONS:

The authors concluded that increased EGFR expression occurs in a fraction of patients who have RCC with an unfavorable histologic phenotype. EGFR copy number gain represents 1 possible cause for EGFR overexpression; however, many over expressing tumors have a normal genotype. High polysomy (which is suggested to be predictive of a response to tyrosine kinase inhibitors) occurs in 5.6% of RCCs. Thus, the potential utility of anti‐EGFR medications may be worth further investigation in a small but significant subset of patients with RCC. Cancer 2012;. © 2011 American Cancer Society.  相似文献   
905.
906.
Diabetic foot skin close to an ulcer shows only a few infiltrating cells compared to nondiabetic inflamed tissues. Diabetes is characterized by thickened basement membrane of the blood arterioles and capillaries. This may affect the transcapillary transport of immune humoral factors and cells to the extravascular space. We analyzed by immunohistochemistry the phenotype and expression pattern of adhesion molecules on leukocyte, dermal fibroblast, and endothelial cells in diabetic foot ulcers. Although there was accumulation of granulocytes on the surface and superficial layers of the granulation tissue, rare perivascular granulocyte infiltrates in the dermis were seen. Moreover, lack of macrophage and CD3+ T cell infiltrates was observed. In contrast, there was increased intensity of CD1a staining of Langerhans cells in the epidermis and papillary dermis (p < 0.05). Fibroblasts revealed increased presence in the ulcer margins compared with normal skin (p < 0.05). Skin endothelial cells expressed stronger von Willebrand factor and E-selectin compared with normal skin (p < 0.05). Our study provides evidence that increased expression of endothelial cell adhesion molecules responsible for immunocyte extravasation is not associated with increased inflammatory cell infiltration of the ulcerated diabetic foot tissue. We suggest that the healing process of diabetic foot ulcers may be hampered by mechanisms decreasing accumulation of leukocytes. This implies that pharmacological or biological stimulation of leukocyte extravasation into the ulcer tissue should be tried.  相似文献   
907.
Ohne ZusammenfassungMit 4 Textabbildungen.  相似文献   
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