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101.
Selective IgA deficiency (IgAD) is the most common form of primary immunodeficiency. Its association with genes within the major histocompatibility complex (MHC) has been repeatedly reported. Recently the susceptibility gene has been located in the class III region, around the tumor necrosis factor (TNF) cluster. In this study we have examined IgAD association with TNF-alpha gene promoter polymorphisms and TNFa and b microsatellites. No significant association was found with the former polymorphisms and the observed associations with TNFa2 allele and haplotypes TNFa2b1 and TNFa2b3 were proven to be secondary to their occurrence on the B14-DR1 and B8-DR3 haplotypes, previously reported to be associated with susceptibility to IgAD. However, a primary negative (protective) association was found between the TNFa10 allele and IgAD.  相似文献   
102.
Osteosarcoma (OS) displays complex karyotypes with numerical changes as well as structural abnormalities suggesting that several oncogenes and tumor suppressor genes may be implicated in the biology of OS. The aim of our study was to investigate the possible implication of the molecular alterations of the G1 to S-phase checkpoint genes in the pathogenesis of OS. We analyzed samples from 29 patients and found molecular alterations of the RB and TP53 genes in 6 (21%) and 3 (10%) cases, respectively. Homozygous deletion of the INK4A/ARF locus and methylation of INK4A was detected in 3 (10%) and 2 (7%) cases, respectively. CDK4 and MDM2 co-amplification was observed in 1 case (3%). Cyclin D3 is differentially expressed in a greater proportion than D1- and D2-type cyclins. Cytogenetically, all cases had complex karyotypes being especially significant the losses of the chromosomes 4, 13, and 17. As a whole, 11 of 29 (38%) analyzed OS presented alterations in some of the analyzed G1 to S-phase checkpoint genes. These alterations were more frequently present in adults (P = 0.032). All patients with genetic alterations in the G1/S-phase checkpoint died during their clinical follow-up, whereas more than 53% of the remaining cases were alive in this period (P = 0.007). Hence, in the pathogenesis of human OS, deregulation of the G1/S checkpoint genes, especially RB, TP53, and INK4/ARF locus, plays an important role and defines a subgroup of patients with a poor outcome.  相似文献   
103.
Idiopathic achalasia is a motility disorder of the esophagus whose etiology is unknown. An association between HLA genes and susceptibility to achalasia which suggests a possible immunogenetic mechanism has been reported recently. This study was designed to examine the HLA class II association in a large group of achalasia patients further and to investigate the distribution of TNFa and TNFb microsatellites in these patients. The study population, all Spanish, white and unrelated, consisted of 115 consecutive patients and 339 healthy controls. All of the patients had been diagnosed with primary achalasia of the esophagus with manometric, radiographic and endoscopic studies. All studies were performed on DNA samples after locus-specific amplification with the polymerase chain reaction: HLA-DRB1, DQA1 and DQB1 were typed by dot-blot hybridization and the size of the TNFa and TNFb microsatellites was measured using a semiautomatic method. The broad allele HLA-DQ1 was seen to be weakly associated with achalasia. The TNFa11 allele and the DRB1*1501-DQA1*0102-DQB1*0602 haplotype were reduced in achalasia patients but the stratified analyses showed that this was true only when both were present in the same individual. These results confirm the association between achalasia and HLA-DQ1 allele and suggest that TNFa11 is a marker for a protective allele for the disease, present on the B7-DRB1*1501 (7.1) ancestral haplotype in our population.  相似文献   
104.
Deep venus thrombosis may result in pulmonary embolism. In rare instances, embolization has occurred, not directly to the pulmonary arterial tree, but to the right heart chambers. Although the value of echocardiography in the diagnosis is well recognised, their is no consensus for the appropriate treatment. We report herein six cases of floating right atrial thrombi, diagnosed by echocardiography, in patients with pulmonary embolism, or unexplained shock or syncope. Surgical embolectomy was carried out in 4 patients, and thrombolytic therapy in 2, without in-hospital mortality. The high mortality associated to this entity may be improved by rapid echocardiographic recognition and emergency treatment with thrombolysis or surgery. Our data suggest the possible use of thrombolysis as a first-choice therapy in selected patients.  相似文献   
105.
BACKGROUND: although the etiology of ulcerative colitis disease remains an enigma, the importance of the major histocompatibility complex genes has been described, as in many other autoimmune diseases. AIM: we investigated the contribution of HLA-DRB1, DQA1 and DQB1 genes (HLA region) in patients with pancolitis. METHODS: we studied a total of 89 patients diagnosed as having ulcerative colitis (34 pancolitis and 55 left colitis) and 275 healthy control subjects. Complete information on sex, age, family history, age of onset, localization, complications, surgery and treatment was obtained from all patients. DNA was extracted from peripheral blood leukocytes and all individuals were HLA-DRB1 genotyped. RESULTS AND CONCLUSIONS: there was an association between pancolitis and the presence of DR4-Val86 (p = 0.009; OR = 3.3) and DRB1*0103 (p = 0.02; OR = 5.1) alleles. In patients with left colitis an association with DRB1*1501 (p = 0.03; OR = 1.9) and DRB1*0103 alleles (p = 0.03; OR = 3.8) was observed. We conclude that a strong association between DR4-Val86 and pancolitis exists.  相似文献   
106.
TNFRSF6B and TNFRSF14 genes were recently associated with Crohn's disease and rheumatoid arthritis. TNFRSF14 is known as herpes virus entry mediator (HVEM), and herpes viruses have been involved in the aetiology of multiple sclerosis (MS). MS patients present human herpes virus 6 (HHV6) in active plaques and increased antibody responses to HHV6. We aimed to ascertain the role of these genes in MS susceptibility and to investigate the relationship of the gene encoding the widely expressed HVEM receptor with the active replication of HHV6 found in some MS patients. Genotyping of 1370 Spanish MS patients and 1715 ethnically matched controls was performed. HHV6A DNA levels (surrogate of active viral replication) were analysed in serum of MS patients during a 2-year follow-up. Both polymorphisms were associated with MS predisposition, with stronger effect in patients with HHV6 active replication-TNFRSF6B-rs4809330(*)A: P=0.028, OR=1.13; TNFRSF14-rs6684865(*)A: overall P=0.0008, OR=1.2; and HHV6-positive patients vs controls: P=0.017, OR=1.69.  相似文献   
107.
Tumor necrosis factor-α (TNF-α) is a pleiotropic pro-inflammatory cytokine with potentially neurodestructive effects and plays a pivotal role in autoimmune demyelinating disease. To address the role of TNF-α in the pathogenesis of experimental autoimmune neuritis (EAN), the current study investigated the antigen-presenting capacity of Schwann cells (SCs) in EAN induced by P0 protein peptide 106–125 in TNF-α recepter 1 deficient (TNFR1−/−) mice. The antigen-presenting capacity of SCs was assessed by the expression of MHC class II (MHCII), CD40, CD80 and CD86 molecules on activated SCs as well as by induction of T cell proliferation in co-cultures of P0 protein peptide 106–125 specific T cells with activated SCs. In addition, the expression of inducible nitric oxide synthase (iNOS) was measured in activated SCs by flow cytometry. TNFR1−/− EAN mice developed significantly delayed and reduced clinical signs of EAN compared to wild type EAN mice. In parallel, the expression of MHCII, CD80 and iNOS on SCs were decreased in TNFR1−/− mice compared to wild type mice. Likewise, proliferation of P0 protein peptide 106–125 specific T cells simulated by activated SCs of TNFR1−/− EAN mice was lower than that of wild type EAN mice. Our data suggest that TNF-α may exert pro-inflammatory effects in EAN via TNFR1 by up-regulating the antigen-presenting function and iNOS production of SCs.  相似文献   
108.
109.
A 54-year-old woman presented a peri-areolar nodule located in the skin of the right breast. Clinical examination showed a 6 x 5 cm exophytic, lobed, ulcerated, and bleeding nodule. The patient reported that the tumor had grown gradually over a period of 3 months. The patient had been diagnosed 8 years prior to presentation with infiltrating ductal carcinoma of the right breast (pT2NO). This tumor was treated with partial mastectomy (conservative surgery) and lymph node dissection, then subsequently received 30 tangent field radiotherapy sessions to the breast for a total dose of 45 Gy. The rest of her cutaneous exam was normal. There was no family history of any similar tumor.  相似文献   
110.

Introduction

Prostate cancer (PC) is one of the tumours with the highest incidence in recent years. PC therapies have several adverse effects. A panel consensus recommendation has been made to prevent or ameliorate complications in PC treatment to improve quality of life.

Material and methods

Fifteen specialists have met to analyse the different toxicities associated with PC treatment. Each medical specialist performed a National Library of Medicine PubMed search citations searching about these secondary effects and his speciality from 1999 to 2009 to propose measures for their prevention/amelioration.

Results

Surgery is associated with incontinence and impotence. Radiotherapy can produce acute, late urological and gastrointestinal toxicity. Brachytherapy can produce acute urinary retention. Chemotherapy is associated with haematotoxicity, peripheral neuropathy and diarrhoea, and hormone therapy can produce osteoporosis, metabolic syndrome, cognitive and muscular alterations, cardiotoxicity, etc.

Conclusions

Improvement in surgical techniques and technology (IMRT/IGRT) can prevent surgical and radiotherapeutic toxicity, respectively. Brachytherapy toxicity can be prevented with precise techniques to preserve the urethra. Chemotherapy toxicity can be prevented with personalised schedules of treatment and close follow-up of iatrogenia and hormone therapy toxicity can be prevented with close follow-up of possible secondary effects.  相似文献   
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