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Various studies have evaluated the possible role of the -1438G/A polymorphism within the 5-HT2A receptor gene in the susceptibility to Eating Disorders (EDs). One hundred and forty-eight ED patients (EDp) and 89 control subjects were interviewed by means of the Eating Disorder Examination (EDE) and analyzed for distribution of the -1438G/A polymorphism. Patients with the AA genotype suffering from Anorexia Nervosa and Bulimia Nervosa showed higher Weight and Shape Concern (P = 0.003 and P = 0.010, respectively) scores and greater overall severity of the ED psychopathology (EDE total score) (P = 0.012). The obtained preliminary data suggest the use of dimensional psychopathological measures in ED genetic studies.  相似文献   
13.
X-linked nonspecific mental retardation (MRX) accounts for approximately 25% of mental retardation in males. A number of MRX loci have been mapped on the X chromosome, reflecting the complexity of gene action in central nervous system (CNS) specification and function. Eleven MRX genes have been identified, but many other causative loci remain to be refined to the single gene level. In 21 MRX families, the causative gene is located in the pericentromeric region; and we report here the identification by linkage analysis of a further such locus, MRX81. The new MRX locus was identified by two- and multi-point parametric analysis carried out on a large Italian family. Tight linkage of MRX81 to DNA markers ALAS2, DXS991, and DXS7132 was observed with a maximum LOD score of 3.43. Haplotype construction delineates an MRX81 critical region of 8 cM, the smallest MRX pericentromeric interval so far described, between DXS1039 and DXS1216, and placing it in Xp11.2-Xq12. So far, automated sequencing of two candidates in the region, the MRX gene oligophrenin (OPHN1) and the brain-specific ephrinB1 (EFNB1) gene, in DNA from affected males excluded their candidacy for MRX81, suggesting a novel disease gene.  相似文献   
14.
Persistent productive HIV infection in EBV-transformed B lymphocytes   总被引:3,自引:0,他引:3  
The susceptibility to HIV infection of 14 B-cell lines established from five healthy HIV seronegative and from six HIV seropositive subjects by lymphocyte transformation with EBV and/or by lymphocyte cultivation with cyclosporin A was studied. Although the cell lines contained different proportions of CD4-positive cells, as shown by flow cytometry, all of them could be infected with the SF-2 strain of HIV. Infection was blocked by a monoclonal antibody directed against the viral attachment site of the CD4 molecule, even in a line that lacked demonstrable CD4 receptors. B-cell lines with high proportions of CD4-expressing cells produced HIV p24 antigen more rapidly and at higher concentrations than cell lines with low CD4 expression. Although HIV infection resulted in some cytopathic effects, it was possible to cultivate the infected cells for more than 8 months without refeeding the cultures with uninfected cells. Even in long-term cultures, there was a continuous production of infectious HIV, as detected by transfer of culture supernatants to other susceptible cell lines. The production of viral antigens was consistently more pronounced in the B-cell line with the highest CD4 positivity than it was in a permissive T-cell line (HUT-78) infected in the same manner. These results indicate that HIV can chronically and productively infect transformed B cells via interaction with CD4 molecules. Thus it is possible that B cells may constitute a source of infectious virus in HIV-infected EBV-positive individuals.  相似文献   
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Several genes with an essential role in the regulation of eating behavior and body weight are considered candidates involved in the etiology of eating disorders (ED), but no relevant susceptibility genes with a major effect on anorexia nervosa (AN) or bulimia nervosa (BN) have been identified. Brain-derived neurotrophic factor (BDNF) has been implicated in the regulation of food intake and body weight in rodents. We previously reported a strong association of the Met66 allele of the Val66Met BDNF variant with restricting AN (ANR) and low minimum body mass index in Spanish patients. Another single nucleotide polymorphism located in the promoter region of the BDNF gene (-270C>T) showed lack of association with any ED phenotype. In order to replicate these findings in a larger sample, we performed a case-control study in 1142 Caucasian patients with ED consecutively recruited in six different centers from five European countries (France, Germany, Italy, Spain and UK) participating in the 'Factors in Healthy Eating' project. We have found that the Met66 variant is strongly associated to all ED subtypes (AN, ANR, binge-eating/purging AN and BN), and that the -270C BDNF variant has an effect on BN and late age at onset of weight loss. These are the first two variants associated with the pathophysiology of ED in different populations and support a role for BDNF in the susceptibility to aberrant eating behaviors.  相似文献   
17.
Introduction: Growth failure in children is a frequent feature of childhood-onset Crohn’s disease (CD), and stunting can persist into adulthood. Growth is an important outcome by which to judge the effectiveness of therapies in children; currently available studies in CD children have focused on the short-term impact of treatments on growth, and there are limited data regarding the long-term effects of treatments upon growth.

Areas covered: We designed the present article to review whether the first treatment performed in newly diagnosed CD children may have a role on the future growth course. We conducted a systematic literature search to identify relevant studies published on the PubMed database from January 2002 up to now. We found only six surveys that documented mid-term growth course in newly diagnosed CD patients.

Expert commentary: In the last years there have been relevant advances in the clinical management of CD children; however, there is a lack of knowledge about the best strategy to reverse growth failure. Children treated with enteral nutrition have appropriate height and weight gain but do not reverse the growth course. Further surveys are required to better explore not only clinical outcomes but also long-term growth course following each therapeutic strategy.  相似文献   

18.
Ti-6Al-7Nb samples treated by innovative multi-step chemical and thermal processes were characterized in order to evaluate their surface properties and cell interaction. The main object was to asses if the treatments were effective in order to obtain a surface presenting at the same time bone-like apatite induction ability, low metal ion release, good cell response and high protein binding. The morphology, crystallographic structure, porosity and wettability of the treated materials were investigated, as well as their interaction with simulated body fluid during soaking for different times. Cytotoxicity, protein adsorption tests and in vitro fibroblast and osteoblast-like cell cultures were also performed.  相似文献   
19.
In the past 6 years we have encountered 26 cases of fatal adenoviral pneumonia in six species of simian primates. O these, 22 animals were between 11 and 38 days old at the time of death, and pneumonia was the primary clinical disease. The spectrum of clinical disease varied from peracute fatal disease to inapparent disease with seroconversion. In one outbreak involving 4 infants housed together in an isolation unit, simian virus 11 was isolated from 3 of the infants and seroconversion occurred in all 4. At necropsy the lungs were voluminous, with firm gray areas of consolidation. On histopathologic examination, severe patchy necrotizing alveolitis and bronchiolitis were present. Variable edema and hyaline membrane formation, alveolar epithelial hyperplasia, and secondary bacterial pneumonia were also seen. Large basophilic intranuclear inclusions were present in bronchiolar and alveolar epithelial cells in all 26 cases. In 4 of 8 cases examined ultrastructurally typical intranuclear paracrystalline arrays of adenoviral virions were demonstrated. Intranuclear inclusion bodies were also observed occasionally in bile duct and pancreatic duct epithelium. Simian adenoviral pneumonia can be a spontaneous disease problem in laboratory-reared primates and offers excellent potential as an animal model of human adenoviral pneumonia.  相似文献   
20.
Our purpose was to review and analyse the impact of pyrethroids and organophosphates exposure on human semen parameters. A comprehensive literature search was performed through MEDLINE via PubMed, Scopus and Webscience. Only cohort studies examining semen parameters in workers or general populations exposed to pyrethroids or organophosphates were included. Ejaculate volume, sperm count, concentration, motility, viability, normal morphology and seminal pH alterations were pooled using the Cochran–Mantel–Haenszel Method with the random effect model and expressed as weighted mean difference, risk ratios, 95% confidence intervals and p-values. Seven cross-sectional studies regarding pyrethroids were included. Four of them were eligible for meta-analysis. The only parameter affected by pyrethroid exposure was normal sperm morphology (WMD-7,61%, 95%CI –11,92 to −3,30;p = 0,0,005). Nine studies were selected to evaluate the impact of organophosphates on semen parameters with six of them eligible for meta-analysis. A significant reduction was detected for the following: ejaculate volume (WMD −0,47ml, 95%CI −0,69 to −0,25; p < 0,0001), sperm count (WMD-40,03, 95%CI −66,81 to −13,25;p = 0,003), concentration (WMD-13,69 x10⁶/mL, 95%CI −23, 27 to-4,12;p = 0,005) and motility (WMD −5,70%, 95%CI −12,89 to 1,50;p = 0,12). Despite the increase in sperm abnormality, it has been shown that pyrethroids are unrelated to reduced sperm quality. However, the negative association of organophosphates with spermatogenesis is noteworthy.  相似文献   
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