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1.
Microbial transformation of zearalenone to a zearalenone sulfate.   总被引:2,自引:0,他引:2       下载免费PDF全文
The conversion of zearalenone by various microorganisms was studied. A new polar metabolite was formed in addition to alpha- and beta-zearalenols. The structure of the new metabolite was determined as zearalenone-4-O-sulfate conjugate on the basis of enzymatic and acid hydrolysis, followed by mass spectrometry, nuclear magnetic resonance, and infrared spectroscopic analysis. The results obtained demonstrate that Rhizopus arrhizus catalyzes sulfation of zearalenone at the C-4 hydroxyl group.  相似文献   
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OBJECTIVE:

This cross-sectional study was undertaken to construct the new body fat % curve and provide body composition reference data for adolescent girls with Turner syndrome (TS). They diagnosed cytogenetically by blood karyotyping and not treated with growth hormone (GH).

MATERIALS AND METHODS:

The study included 70 TS girls from age 13 years to age 17 years. Body composition was measured by bioelectrical impedance. Smoothed centile charts were derived by using the least mean square (LMS) method.

RESULTS:

The new body fat curves reflect the increase of body fat mass (FM) from age 13 years to age 17 years. Body FM % of Egyptian TS girls was lower when compared with age-matched American untreated TS girls.

CONCLUSION:

This study presents the new body fat curves and reference values of body composition for untreated Egyptian TS adolescent girls. The present charts can be used for direct assessment of body FM % for Egyptian TS girls and evaluation for cases on GH treatment or other growth promoting therapy.  相似文献   
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Introduction  

Monocytes/macrophages accumulate in the rheumatoid (RA) synovium where they play a central role in inflammation and joint destruction. Identification of molecules involved in their accumulation and differentiation is important to inform therapeutic strategies. This study investigated the expression and function of chemokine receptor CCR9 in the peripheral blood (PB) and synovium of RA, non-RA patients and healthy volunteers.  相似文献   
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This study aimed to investigate the association among genetic variants of the complement pathway CFB R32Q (rs641153), C3 R102G (rs2230199), and CFH (rs1410996) with age-related macular degeneration (AMD) in a sample of the Brazilian population. In a case-control study, 484 AMD patients were classified according to the clinical age-related maculopathy grading system (CARMS) and compared to 479 unrelated controls. The genetic variants rs1410996 of complement H (CFH), rs641153 of complement factor B (CFB), and rs2230199 of complement 3 (C3) were evaluated through polymerase chain reaction (PCR) and direct sequencing. The associations between single nucleotide polymorphisms (SNPs) and AMD, adjusted by age, were assessed by using logistic regression models. A statistically significant association was observed between AMD risk and rs2230199 variant with an OR of 2.01 (P  = 0.0002) for CG individuals compared to CC individuals. Regarding the comparison of advanced AMD versus the control group, the OR was 2.12 (P = 0.0036) for GG versus AA genotypes for rs1410996 variant. Similarly, the OR for rs2230199 polymorphism was 2.3034 (P  = 5.47e-05) when comparing CG individuals to CC carriers. In contrast, the rs641153 variant showed a significant protective effect against advanced AMD for GA versus GG genotype (OR = 0.4406; P  = 0.0019). When comparing wet AMD versus controls, a significant association was detected for rs1410996 variant (OR = 2.16; P  = 0.0039) comparing carriers of the homozygous GG versus AA genotype, as well as in the comparisons of GG (OR = 3.0713; P  = 0.0046) and CG genotypes (OR = 2.2249; P  = 0.0002) versus CC genotype for rs2230199 variant, respectively. The rs641153 variant granted a significant protective effect against wet AMD for GA versus GG genotypes (OR = 0.4601; P  = 0.0044). Our study confirmed the risk association between rs2230199 and rs1410996 variants and AMD, and the protective role against AMD for rs641153 variant.  相似文献   
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Mandibuloacral dysplasia (MAD) is a rare disorder. Only 35 patients, coming from 22 families, have been reported worldwide. We report on two Egyptian unrelated girls with MAD. The first patient presented at the age of 5 years with acral defect and partial alopecia. The second patient presented at the age of 17 years with progressive micrognathia and loss of subcutaneous fat from the limbs. Physical examination detected the craniofacial, skeletal and cutaneous changes characteristic of MAD. Both patients were short with progeroid facies and loss of subcutaneous fat from the extremities, which fits lipodystrophy type A pattern. Radiological examination revealed delayed closure of cranial sutures, hypoplastic mandible, hypoplastic clavicles, and acroosteolysis. Both patients had normal glucose tolerance, but had fasting and post-prandial hyperinsulinemia, suggestive of insulin resistance. One patient had elevated serum triglycerides and low normal cholesterol levels, while the other patient had normal levels. Serum leptin was normal in both patients. We review the literature on mandibuloacral dysplasia and discuss the differential diagnosis.  相似文献   
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ABSTRACT: BACKGROUND: Avian influenza virus H9N2 is a panzootic pathogen that affects poultry causing mild to moderate respiratory distress but has been associated with high morbidity and considerable mortality. Interspecies transmission of H9N2 from avian species to mammalian hosts does occur. The virus possesses human virus-like receptor specificity and it can infect humans producing flu-like illness. METHODS: Recently, mild influenza like symptoms were detected in H5N1 vaccinated flocks. Influenza A subtype H9N2 was isolated from the infected flock. The virus evolution was investigated by sequencing the viral genes to screen the possible virus recombination. The viral amino acid sequences from the isolated H9N2 strains were compared to other related sequences from the flu data base that were used to assess the robustness of the mutation trend. Changes in the species-associated amino acid residues or those that enabled virulence to mammals were allocated. RESULTS: Phylogenetic analyses of haemagglutinin and neuraminidase genes showed that the recently isolated Egyptian strain belonged to the H9N2 sub-lineage that prevails in Israel. The six internal segments of the isolated virus were found to be derived from the same sub-lineage with no new evidence of reassortment. The results demonstrated conserved genetic and biological constitution of H9N2 viruses in the Middle East. The recently isolated H9N2 virus from chicken in Egypt possessed amino acids that could enable the virus to replicate in mammals and caused severe disease in domestic chickens. CONCLUSION: The study highlights the importance of continuous monitoring of the mutations evolved in avian influenza viruses and its impact on virulence to avian species in addition to its importance in the emergence of new strains with the capacity to be a pandemic candidate.  相似文献   
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Jacobsen syndrome is a rare disorder, caused by segmental monosomy for the distal end of the long arm of chromosome 11 with variable phenotypic expressivity. We report on the first male (6 years old) and female (3 years old) sibs with clinical and cytogenetics characterization of Jacobsen syndrome. Their karyotypes showed deletion 11q23.3-qter. Patients presented with growth and psychomotor retardation, facial dysmorphism, eye anomalies, and congenital heart disease (variable degrees of septal defect). Family history revealed a clinically similar brother, who died at 2 months old from cardiac anomalies in the form of single ventricle without being subjected to further investigations. Chromosomal analysis of the parents was normal. Karyotyping for the 2 patients and their parents was confirmed by fluorescence in situ hybridization analysis (FISH) using whole chromosome painting probes for 11 (WCP 11). Relevant investigations for both sibs showed mild thrombocytopenia with normal platelets morphology and striking periventricular demyelination on neuroimaging. Inguinal small testicles as well as focal epileptiform dysfunction were recorded in the male patient only. Abdominal ultrasound, hearing test, and DEXA scan were normal in both patients. Due to of the presence of apparently 3 affected offspring and normal parental karyotypes, an inherited predisposition was highly suspected. The large size of the distal deleted 11q segment in our patients support the recent hypothesis, that Jacobsen syndrome is a chromosomal deletion syndrome with genetic predisposition, due to expansion of p(CCG)n trinucleotide in the folate-sensitive fragile site FRA11B, at breakpoint 11q23.3. In conclusion, identification and further delineation of more similar patients will contribute to understanding the genetic basis of the 11q phenotype.  相似文献   
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