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91.
Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant and age-dependent vascular disorder originated by mutations in Endoglin (ENG) or activin receptor-like kinase-1 (ALK1, ACVRL1) genes. The first large series HHT analysis in Spanish population has identified mutations in 17 unrelated families. Ten different mutations in ALK1 and six in ENG genes were found. Six unrelated families had a mutation in ENG gene, four representing new mutations, p.Y258fs, pV323fs, p.F279fs (c.834_837del CTTC), and p.F279fsdupC. Eleven unrelated families harboured mutations in ALK1; ten were new mutations identified as p.H328P, p.R145fs, p.G68C, p.A377T, p.H297R, p.M376T, p.C36Y, p.H328P, p.T82del and p.R47P. Overall, ALK1 mutations (HHT2) were predominant over ENG mutations (HHT1), in agreement with data reported for other Mediterranean countries (France, Italy), but at variance with Northern Europe or North America. Endoglin expression in HHT1 or HHT2 activated monocytes and blood outgrowth endothelial cells (BOECs) from older patients was well below the theoretical 50% level expected from the HHT1 haploinsufficiency model, suggesting that the pathogenic endoglin haploinsufficiency leading to the HHT phenotype is age-dependent. Interestingly, ALK1 protein levels of HHT BOECs in some missense ALK1 mutants were similar to controls. In vitro expression of these ALK1 constructs suggests that, in addition to the haploinsufficiency model, certain ALK1 mutants may inhibit the function of the wild type allele.  相似文献   
92.
Many reports provided strong evidence of the influence of genetic factors in the pathogenesis of psoriasis (Ps). A higher prevalence of lipid disorders in psoriatic patients has been reported. Because apolipoprotein E (apoE) is involved in lipid metabolism, APOE gene variants could be candidates to influence Ps-risk. However, data about the potential influence of the APOE genotypes in Ps are inconclusive. Our objective was to investigate the relationship between the common APOE-ε2/ε3/ε4 variation and Ps in a Caucasian population. Our study involved 331 unrelated Ps-patients and 400 healthy controls. Patients and controls were genotyped for the APOE-ε2/ε3/ε4 polymorphism, and allele and genotype frequencies were statistically compared between the two groups and between patients according to disease severity. Mean lipid values were also compared between the APOE genotypes. Allele and genotype frequencies did not differ between patients and controls. APOE-ε4 carriers were significantly more frequent in patients with severe Ps compared to controls (P = 0.003) and to non-severe Ps (P = 0.017). No significant difference in mean lipid values was found between the APOE genotypes. The APOE-ε4 allele could be a risk factor for developing a severe form of psoriasis.  相似文献   
93.
Individuals who are at risk for autosomal dominant polycystic kidney disease are often screened by ultrasound using diagnostic criteria derived from individuals with mutations in PKD1. Families with mutations in PKD2 typically have less severe disease, suggesting a potential need for different diagnostic criteria. In this study, 577 and 371 at-risk individuals from 58 PKD1 and 39 PKD2 families, respectively, were assessed by renal ultrasound and molecular genotyping. Using sensitivity data derived from genetically affected individuals and specificity data derived from genetically unaffected individuals, various diagnostic criteria were compared. In addition, data sets were created to simulate the PKD1 and PKD2 case mix expected in practice to evaluate the performance of diagnostic criteria for families of unknown genotype. The diagnostic criteria currently in use performed suboptimally for individuals with mutations in PKD2 as a result of reduced test sensitivity. In families of unknown genotype, the presence of three or more (unilateral or bilateral) renal cysts is sufficient for establishing the diagnosis in individuals aged 15 to 39 y, two or more cysts in each kidney is sufficient for individuals aged 40 to 59 y, and four or more cysts in each kidney is required for individuals > or = 60 yr. Conversely, fewer than two renal cysts in at-risk individuals aged > or = 40 yr is sufficient to exclude the disease. These unified diagnostic criteria will be useful for testing individuals who are at risk for autosomal dominant polycystic kidney disease in the usual clinical setting in which molecular genotyping is seldom performed.  相似文献   
94.
OBJECTIVE: To investigate (i) the association between four serotonergic polymorphisms (A-1438G and T102C of the 5-HT2A receptor gene, and 5-HTT VNTR and 5-HTTLPR of the 5-HT transporter gene) and schizophrenia and (ii) the potential interaction of those polymorphisms in the development of schizophrenia. SUBJECTS AND METHODS: 227 outpatients with schizophrenia (DSM-IV criteria) and 420 unrelated healthy controls from Asturias (Northern Spain) were genotyped using standard methods. RESULTS: Both groups showed Hardy-Weinberg equilibrium for the analyzed genetic variability. A-1438G and T102C polymorphisms are in complete linkage disequilibrium in our population. There was an apparent difference in the distribution of genotypes for the A-1438G (or T102C) polymorphisms (p=0.018, not significant after a Bonferroni correction). The 5-HT2A -1438A (or 102T) allele was significantly more frequent in patients than controls (0.53 and 0.45, respectively; corrected p=0.028, OR=1.39 (95% CI=1.11-1.75)). Genotype and allele distributions for 5-HTT polymorphisms were similar in both groups. However, assessment of the combined influence of 5-HT2A A-1438G and 5-HTTLPR polymorphisms demonstrated a significant effect (chi(2) (3)=11.51, p=0.009), whereby the combination of -1438A and 5-HTTLPR S alleles was associated with schizophrenia. CONCLUSIONS: Our findings support a possible synergistic effect of genetic factors influencing serotonergic neurotransmission on susceptibility to schizophrenia.  相似文献   
95.

Background  

An association between a common deletion comprising the late cornified envelope LCE3B and LCE3C genes (LCE3C_LCE3B-del) and Psoriasis (Ps) has been reported. The expression of these LCE genes was induced after skin barrier disruption and was also strong in psoriatic lesions. The damage to the skin barrier could trigger an epidermal response that includes the expression of genes involved in the formation of skin barrier.  相似文献   
96.
97.
The folate availability seems to be critical for the DNA integrity since it is required for the transfer of methyl groups in the biosynthesis of thymidilate. Although the excessive incorporation of uracils to the DNA can be efficiently removed, this mechanism of reparation produces many double-strand breaks from two opposing nicks. Several chromosomal abnormalities (mainly translocations and deletions perhaps not well understood) are involved in the origin of lymphoproliferative disorders. The TT homozygosity at nucleotide 677 in the gene of methylene tetrahydrofolatereductase (MTHFR), a key enzyme in folate metabolism, was recently linked to a significant protection against colon carcinoma and acute lymphoblastic leukaemia in adults. We analysed the genotype frequencies of C677T-MTHFR in a group of 143 patients with lymphoproliferative disorders (REAL classification) and 200 controls. Overally, the frequencies of the polymorphic allele were similar (35.3% and 32.0% respectively)(P=0.6). We did not find differences between patients and controls except for myeloma/plasmacytoma group (n=26) which showed a CC genotype less than expected (19% vs 46%) (p=0.01) with a frequency ratio of 0.28 (0.10-0.77). Even among the IgG myeloma cases only one patient showed a common genotype (CC) (1/15, 7%) (P=0.003). If these preliminary data are validated with prospective studies, the 677C allele of MTHFR gene could be confirmed as an effective multiple myeloma protective factor (specially for the IgG cases).  相似文献   
98.
OBJECTIVE: To validate and promulgate a core set of outcome measures for the evaluation of response to treatment in patients with juvenile systemic lupus erythematosus (SLE). METHODS: In 2001, a preliminary consensus-derived core set of measures for evaluating the response to therapy in juvenile SLE was established. In the present study, the core set was validated through an evidence-based, large-scale data collection process that led to the enrollment of 557 patients from 39 different countries. Consecutive patients with active disease were assessed at baseline and after 6 months. The validation procedures included assessment of feasibility, responsiveness, discriminant and construct ability, agreement in the evaluation of response to therapy between physicians and parents, redundancy, internal consistency, and ability to predict a therapeutic response. RESULTS: The following clinical measures were found to be feasible and to have good construct validity, discriminative ability, and internal consistency; furthermore, they were not redundant, proved responsive to clinically important changes in disease activity, and were associated strongly with treatment outcome and thus were included in the final core set: 1) physician's global assessment of disease activity, 2) global disease activity measure, 3) 24-hour proteinuria, 4) parent's global assessment of the patient's overall well-being, and 5) health-related quality of life assessment. CONCLUSION: The members of PRINTO propose a core set of criteria for the evaluation of response to therapy that is scientifically and clinically relevant and statistically validated. The core set will help standardize the conduct and reporting of clinical trials and assist practitioners in deciding whether a patient with juvenile SLE has responded adequately to therapy.  相似文献   
99.
The aim of this study was to explore differences in the cytokine profile among de novo kidney transplant recipients treated with either Rapamycin (Rapa) + cyclosporine (CsA) + prednisone (P) or CsA + azathioprine (Aza) + P.

Patients and methods

Among the 13 adult kidney transplant recipients studied, seven received Rapa + CsA + P while the remaining six received CsA + Aza + P with their living donors serving as controls (n = 13). Spontaneous production of IL-2, IFNγ, IL-10, and TGF-β were measured by ELISA in supernatants from 24-hour cultured unstimulated peripheral blood mononuclear cell (PBMC) at time zero (the day before the transplant), and at 3 and 6 months posttransplant. Cytokines were also measured 1 month after CsA withdrawal in the Rapa + CsA + P group.

Results

From time zero to the end of the study, IL-2, IFNγ, and IL-10 were present at low or undetectable levels in all three groups. TGF-β tended to increase in supernatants from patients under Rapa + CsA + P at 6 months posttransplant and at 1 month after CsA withdrawal without correlation to Rapa blood levels. TGF-β remained stable throughout the study period for patients included in the CsA + Aza + P group. There was no difference in this cytokine level between these study groups at any given time.

Conclusions

This study showed no differences in the spontaneous cytokine profiles evaluated in patients treated with both therapeutic schemes.  相似文献   
100.
BACKGROUND: The coexistence of granuloma annulare (GA) and autoimmune thyroiditis (AT) has been sporadically observed in female patients, but the significance of this rarely reported association remains uncertain. OBJECTIVE: To investigate for the first time the frequency and type of thyroid disease in adult women with localized granuloma annulare (LGA) compared with a matched control group. METHODS: Twenty-four adult women with histology-proven LGA and a control group of 100 age-matched female patients with other unrelated cutaneous diseases were screened for thyroid disease in a tertiary teaching hospital in northern Spain. Laboratory evaluation included routine hematologic and chemistry analysis, antinuclear antibody, rheumatoid factor, thyroid function test (sensitive thyroid-stimulating hormone [TSH]), thyroid autoantibody levels, and antibodies to thyroid peroxidase in all patients and controls. Thyroid hormones (free triiodothyroxine and free thyroxine) were measured when TSH value was abnormal. AT was defined as hypothyroidism (TSH value >5 mU/L) and in addition to elevated antithyroid antibodies or characteristic thyroid biopsy. The results were compared using Fisher's exact test. RESULTS: Statistical evaluation of the findings obtained in this study showed mainly that the frequency of AT was increased significantly in the group of adult women with LGA (3/24, 12%) compared with the matched control group (1/100) (Fisher's exact test: P =.022). CONCLUSION: Although little can be inferred from a single investigation, the results of this pilot study indicate an association between LGA and AT in adult female patients, supporting the theory that at least a subset of GA belongs to the spectrum of autoimmune diseases.  相似文献   
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