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101.
Autism spectrum disorders (ASD) are characterized by a broad range in clinical presentation. Although a definite genetic cause has not yet been fully demonstrated, family based studies suggest that a multigenic pattern may be responsible for susceptibility, but most results are conflicting and have yet to be replicated. The purpose of this investigation was to analyze the linkage of the human leukocyte antigen (HLA) and the human serotonin transporter coding (5-HTTLPR) genes with ASD in a group of 37 families of Sardinian ethnicity in insular Italy. In 50% of these families, ASD is linked to HLA, and in the other 50% it is linked to 5-HTTLPR polymorphic genes; in other words, linkage to one or the other was evident in all cases. Despite a very homogenous genetic pattern being generally reported for Sardinians, the linkage observed with HLA and 5-HTTLPR genetic regions indicated a statistically defined heterogeneity (p=0.002). No allelic HLA or 5-HTTLPR polymorphisms were specifically associated with ASD, suggesting these loci as markers of other genes mapped in their close proximity that may be more directly involved and thus may merit further analytical studies.  相似文献   
102.
Folate receptor family members (FOLRs) mediate the delivery of 5-methyltetrahydrofolate to the interior of, out of within, or between cells in a process known as potocytosis. Three FOLRs and a pseudogene map to 11q13.4. The aim of this study was to verify whether FOLRs could be responsible for the onset of nonsyndromic cleft lip with or without cleft palate (CL/P). Linkage and linkage disequilibrium between genetic markers and disorder were analyzed. Patients and their mothers from 71 familial CL/P pedigrees and 75 sporadic cases from Italian population were investigated by PCR-SSCP analysis. Data from mutation scanning allowed us to find only a silent mutation in FOLR1 present in a mother and her child. Our findings do not support FOLR1 and FOLR2 genes in the onset of CL/P.  相似文献   
103.
Nonsyndromic cleft lip with or without cleft palate (CL/P) affects approximately 1 in 1,000 births. Genetic studies have provided evidence for the role of several genes and candidate loci in clefting; however, conflicting results have frequently been obtained and much have to be done to unravel the complex genetics of CL/P. In the present investigation we have focused on the candidate region in 6p23, a region that have been found linked to CL/P in several investigations, in the attempt to find out the susceptibility gene provisionally named OFC1. Gene expression experiments in mice embryo of positional candidate genes revealed that JARID2 was highly and specifically expressed in epithelial cells in merging palatal shelves. A family‐based linkage disequilibrium study confirmed the pivotal role of JARID2 in orofacial development and strongly supports a role for this gene in CL/P etiology (multiallelic haplotype test P=6×10?5). Understanding the molecular role of JARID2 within facial development may offer additional information to further unravel the complex genetics of CL/P. Hum Mutat 31:1–7, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
104.
To evaluate the potential impact of antipneumococcal vaccination in Italy, Streptococcus pneumoniae isolates from invasive disease were collected from 65 laboratories in the years 1997-2000. Of the 503 isolates examined, 15% were from children <5 years and 34% from adults > or = 65 years. The most frequent serogroups were, in ranking order, 14, 19, 6, and 23. Overall, 93.8% of the isolates belonged to serogroups enclosed in the 23-valent polysaccharide vaccine. Among children isolates, serotypes 14, 6B, and 23F comprised 60% of the isolates; overall, 72% of the isolates belonged to serotypes included in the heptavalent conjugate vaccine. Penicillin nonsusceptible isolates (10%) belonged to a limited number of serogroups, being more common in serogroups 19 and 9 and in the nonvaccine serogroups 24 and 35. Erythromycin-resistant isolates (29%) belonged to several serogroups, more frequently to serogroups 14, 6, and 19. Both vaccines are potentially able to prevent the majority of resistant infections in the respective age groups in Italy.  相似文献   
105.
Sinusoidal obstruction syndrome (SOS), also known as hepatic veno-occlusive disease (VOD), is a serious complication after hematopoietic stem cell transplantation (HSCT). SOS/VOD usually occurs within 3 weeks of HSCT, but the 2016 European Society for Blood and Marrow Transplantation diagnosis criteria have been revised to include late forms. Prophylactic use of defibrotide is recommended in the pediatric setting, but its value remains uncertain in the adult population. We report here a single-center series of 63 adult patients considered at high risk for SOS/VOD who received defibrotide prophylaxis in combination with ursodeoxycholic acid between May 2012 and August 2016. The median duration of defibrotide therapy was 23 days. Bleeding occurred in 14 patients (21.5%). Defibrotide prophylaxis was discontinued in 7 patients (10.8%): 4 cases (6.3%) due to bleeding and 3 cases (4.6%) because of the need for antithrombotic therapy. Overall, SOS/VOD occurred in 4 cases (6.3%) within 21 days after HSCT (days 13 and 14) in 2 cases and late-onset SOS/VOD (days 57 and 58) in the other 2 cases. SOS/VOD was moderate in 1 case, very severe in 3 cases, with 2 deaths related to SOS/VOD. Cumulative incidence of grades II to IV acute graft-versus-host disease and transplant-associated thrombotic microangiopathy were 22.2% and 3.2%, respectively. With a median follow-up of 31 months (range, 10.7 to 60.3), the rates of 2-year overall survival, progression-free survival, incidence of relapse, and nonrelapse mortality were 56.5%, 49%, 28.7%, and 22.3%, respectively. In our experience defibrotide prophylaxis is associated with a low incidence of SOS/VOD after allogeneic HSCT in a high-risk adult population with an acceptable safety profile.  相似文献   
106.
A wait and see approach for desmoid tumors (DT) has become part of the routine treatment strategy. However, predictive factors to select the risk of progressive disease are still lacking. A translational project was run in order to identify genomic signatures in patients enrolled within an Italian prospective observational study. Among 12 DT patients (10 CTNNB1‐mutated and 2 wild type) enrolled from our institution only two patients (17%) showed a progressive disease. Tumor biopsies were collected for whole exome sequencing. Overall, DT exhibited low somatic sequence mutation rate and no additional recurrent mutation was found. In the two wild type (WT) cases, two novel alterations were detected: a complex deletion of APC and a pathogenic mutation of LAMTOR2. Focusing on WT DT subtype, deep sequencing of CTNNB1, APC and LAMTOR2 was conducted on a retrospective series of 11 WT DT using a targeted approach. No other mutation of LAMTOR2 was detected, while APC was mutated in two cases. Low‐frequency (mean reads of 16%) CTNNB1 mutations were discovered in five samples (45%) and two novel intra‐genic deletions in CTNNB1 were detected in two cases. Both deletions and low frequency mutations of CTNNB1 were highly expressed. In conclusion, a minority of DT is WT for either CTNNB1, APC or any other gene involved in the WNT pathway. In this subgroup novel and hard to be detected molecular alterations in APC and CTNNB1 were discovered, contributing to explain a portion of the allegedly WT DT cases.  相似文献   
107.
Immune and inflammatory response activation is a common feature of connective tissue diseases and systemic vasculitis. The aim of our study was to evaluate the possible involvement of TNFα c.-308A > G, IL-10 c.-1082A > G, uteroglobin c.38A > G, TGFβ 1 c.869C > T and NFκB2 c.-1837T > C gene polymorphisms in susceptibility to connective tissue diseases. Our study cohort included 68 unrelated patients affected by rheumatoid arthritis (RA) (37 patients) and ANCA-positive [micropolyangiitis (mPA) 17 patients] or ANCA-negative systemic vasculitis [including 8 patients with Henoch-Schönlein purpura (HSP) and 6 patients with mixed cryoglobulinaemia (MC)] as well as 98 control subjects. Allele frequency analysis of uteroglobin c.38G > A polymorphism showed a significant increase in the c.38A allele in patients (p= 0.002). Genotype frequency analysis of uteroglobin and NF-κB2 gene polymorphisms in patients showed an increase in c.38GA and c.38AA genotypes in the uteroglobin gene (p=0.02) coupled with an increase in homozygous c.-1837CC in the NF-κB2 gene (p=0.02). Our data suggest that genetic variation in UG and NF-κB2 pathways could have effects in connective tissue disease susceptibility.  相似文献   
108.
Matrix metalloproteinases (MMPs) are a family of peptidases trapped within mineralized dentin matrix and involved with degradation of the extracellular matrix components in hybrid layers and caries. Despite their identification through indirect evidences and biochemical assays, MMP-2 and -9 have not been localized within the human dentin extracellular organic matrix. Thus, this study aimed to assess the localization and distribution of MMP-2 and -9 in human dentin organic matrix by employing a correlative field emission in-lens-scanning electron microscopy (FEI-SEM) and transmission electron microscopy (TEM) immunohistochemical approach. Dentin specimens were submitted either to a preembedding or to a postembedding immunolabeling technique using primary monoclonal antibodies anti-MMP-2 and anti-MMP-9 and exposed to a secondary antibody conjugated with gold nanoparticles. MMP-2 and -9 labelings were identified in the demineralized dentin matrix as highly electron-dense gold particles dispersed on the collagen fibrils. Correlative FEI-SEM/TEM observations confirmed that MMP-2 and MMP-9 are endogenous components of the human dentin organic matrix and revealed the three-dimensional relationship between these proteinases and the collagen fibrils, showing that both antibodies yielded a similar labeling pattern. In conclusion, the results of the study contribute to reveal distinct distribution pattern of gelatinases and support the hypothesis that these enzymes are intrinsic constituents of the dentin organic matrix after decalcification.  相似文献   
109.
Loss of menin, a tumor suppressor coded by the MEN1 gene, is a key factor in the pathogenesis of multiple endocrine neoplasia type I and in a percentage of sporadic endocrine tumors of the pancreas and parathyroid glands. This study investigated expression of the menin protein in the normal exocrine pancreas and in pancreatic ductal adenocarcinoma (PDAC), the most common pancreatic tumor. Immunofluorescence (IF) analyses showed that menin is expressed at high levels in normal acinar and duct cells. Examination of 24 clinical samples of PDAC revealed a pronounced decrease in menin expression in all tumors examined. To identify alterations underlying this defect, we searched for disruption and epigenetic silencing of the MEN1 gene. Analysis of nine laser‐microdissected tumors revealed loss of heterozygosity of intragenic (one tumor) or adjacent (three tumors) MEN1 microsatellite markers. Methylation of CpG sites in the MEN1 promoter was documented in five of 24 tumors. IF analyses also revealed low to undetectable menin expression in the PDAC cell lines MiaPaCa‐2 and Panc‐1. Ectopic expression of menin in these cells resulted in a marked alteration of the cell cycle, with an increase in the G1/S+G2 ratio. These findings represent the first evidence that the MEN1 gene is a target of mutation and methylation in PDAC and that menin influences the cell cycle profile of duct cells. © 2009 Wiley‐Liss,Inc.  相似文献   
110.

Background

Since preterm birth is associated with a constellation of pre-, peri- and post-natal risk factors, we hypothesised that prematurity may continue to impact the development of linguistic abilities even up to the end of the preschool years and beyond, giving rise to an atypical developmental trajectory. The study tested this hypothesis at six years of age, investigating whether language is affected by preterm birth and how different linguistic abilities are interrelated.

Method

Seventy monolingual Italian preterms and 34 age-matched controls were recruited. Linguistic abilities (vocabulary, grammar, and phonological awareness) as well as general cognitive developmental levels were measured.

Results

No general cognitive delay emerged, but less developed abilities in vocabulary, grammar, and phonological awareness were found in preterms compared to fullterms. Moreover, the relations among the different linguistic competences differed across groups.

Conclusions

Our study shows that even without brain damage, preterm birth continues to affect linguistic development up to the end of the preschool years, and probably beyond, highlighting a continuity between pre- and peri-natal life and subsequent development, and pointing to an atypical developmental trajectory in this population compared to fullterms (different rates of development, different strategies employed, and differences in the relationships among linguistic abilities).  相似文献   
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