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81.
Autoimmune thyroid diseases (AITD) are the most common organ-specific autoimmune disorders affecting approximately 5% of the overall population. An aberrant interaction between abnormal thyrocytes, abnormal antigen-presenting cells and abnormal T cells forms the basis for the atypical autoimmune reaction targeting thyroid antigens. It was proposed that nongenetic (environmental and hormonal) factors play a crucial etiological role in AITD development, through altering immune-endocrine interactions. The most outstanding fact is that in genetically predisposed individuals, the disruption of these neuroendocrine-immune interactions by environmental factors results in thyroid autoimmune dysfunction. These interactions are able to incline the balance between Th1-Th2 immune response toward one side, resulting in a Th1-cell-mediated autoimmune reaction with thyrocyte destruction and hypothyroidism in Hashimoto's thyroiditis but to a hyperreactive Th2-mediated humoral response against TSH receptor with stimulatory antibodies leading to Graves' disease hyperthyroidism. In this review the main mechanisms involved are summarized. In this sense, the participation of stress-mediated activation of the sympathoadrenal system and hypothalamic-pituitary-adrenal axis, the hormonal changes occurring during pregnancy and postpartum acting on antigen-presenting cells and influencing, in this way, the balance of the immune status are shown to participate in AITD etiology. The possibility that altered levels of thyroid hormones during the course of the AITD may alter immune function is also discussed. 相似文献
82.
A new approach to terminate very early pregnancy was tried on 49 healthy women who were proven to be pregnant from 31 to 47 days from their last menstrual period. All pregnancies were confirmed either by UCG or serum HCG-B subunit. (15S)-15-Methyl PGF2a Methyl Ester in a suppository form was administered in two separate doses: 1.0 mg initial dose followed by 3.0 mg one hour later. Patients were kept under observation for 8 hours. Blood sampling for progesterone, HCG-B, and prostaglandin levels were assayed at 0 °, 30′, 1 °, 4 °, 8 ° and 14 days. Patients were re-examined at a two week follow-up visit. Pelvic examination and pregnancy tests were performed to confirm whether the pregnancy was successfully terminated. There were no significant changes in serums progesterone and HCG-B levels during the 8-hour observation period. Both levels declined significantly to very low levels at 14 days post-therapy, confirming the clinical impression of successful termination of pregnancy. Plasma prostaglandin levels rose as early as 30 minutes after initiation of therapy, peaked at 4 hours and declined gradually afterwards. Most side effects such as nausea, vomiting, diarrhea and cramps, although clinically manageable, were still bothersome. One patient experienced an episode of vasovagal syncope. The majority of patients required medical observation up to 6 hours. Clinical implications of this new approach of termination of very early pregnancy are discussed. 相似文献
83.
Juana Perpiñá-Galvañ Miguel Richart-Martínez María José Cabañero-Martínez 《Archivos de bronconeumologia》2011,47(4):184-189
BackgroundThere is comorbidity between respiratory disease and anxiety. In order to measure the anxiety of hospitalized patients it is necessary to use reliable and valid, and preferably short questionnaires.ObjectiveTo analyze the reliability and validity of a shortened version of the state subscale of the “State-Trait Anxiety Inventory (STAI)” in respiratory patients.Patients and methodsA total of 103 respiratory patients admitted to the respiratory ward between February of 2009 and February of 2010 were non-consecutively selected. They answered two questionnaires: the Spanish version of the STAI-state and a short version consisting of 7 items. Sociodemographic and clinical variables of the patients were also obtained. The internal consistency, and convergent and construct validity of the short scale were analyzed.ResultsThe short scale did not have floor/ceiling effect, the α-Cronbach was acceptable (0.89), and correlated positively (r = 0.90; P =.01) and also maintained the factorial structure of the original scale (half anxiety-present items and half anxiety-absent items).ConclusionsThe short version of the state subscale of the STAI has showed good metric properties in hospitalized respiratory patients. 相似文献
84.
Use of Deoxyribose by Intestinal and Extraintestinal Pathogenic Escherichia coli Strains: a Metabolic Adaptation Involved in Competitiveness 下载免费PDF全文
85.
Rojas OL Caicedo L Guzmán C Rodríguez LS Castañeda J Uribe L Andrade Y Pinzón R Narváez CF Lozano JM De Vos B Franco MA Angel J 《Viral immunology》2007,20(2):300-311
In a double blind trial, 319 fully immunized children received two doses of either placebo or 10(6.7) focus-forming units of the attenuated RIX4414 human rotavirus (RV) vaccine ("all-in-one" formulation). Plasma RV-specific IgA (RV IgA), stool RV IgA, and circulating total and RV memory B cells (CD19+ IgD+/- CD27+) with an intestinal homing phenotype (alpha4beta7+ CCR9+/-) were measured, after the first and second doses, as potential correlates of protection. After the first and/or second dose, 54% of vaccinees and 13% of placebo recipients had plasma RV IgA. Before vaccination, most (95%) of the children (of both study groups) were breast-fed and had stool RV IgA (68.64%). Coproconversion (4-fold increase) after the first and/or second dose was observed in 32.7% of vaccinees and 17.4% of placebo recipients. No significant difference was seen when comparing the frequencies of any subset of memory B cells between vaccinees and placebo recipients. Statistically significant weak correlations were found between plasma RV IgA titers and coproconversion, and several subsets of memory B cells. The vaccine provided 74.8% protection (95% confidence interval, 30.93-92.62) against any RV gastroenteritis and 100% protection (95% confidence interval, 14.53-100) against severe RV gastroenteritis. When vaccinees and placebo recipients were considered together, a correlation was found between protection from disease and plasma RV IgA measured after dose 2 and RV memory (IgD- CD27+ alpha4beta7+ CCR9+) circulating B cells measured after dose 1. However, the correlation coefficients for both tests were low (<0.2), suggesting that other factors are important in explaining protection from disease. 相似文献
86.
Molecular characterization of methicillin-resistant Staphylococcus aureus isolates collected in Asunción, Paraguay 下载免费PDF全文
Mayor L Ortellado J Menacho C Lird G Courtier C Gardon C Meugnier H Bes M Vandenesch F Etienne J 《Journal of clinical microbiology》2007,45(7):2298-2300
We characterized 34 methicillin-resistant Staphylococcus aureus strains isolated in Paraguay in 2005. The strains belonged to two clones. The major clone (sequence type 5 [ST5] or ST221, spa type t149, staphylococcal cassette chromosome mec [SCCmec] type I) was similar to the Cordobes/Chilean clone spreading through South America, and the minor clone (ST239 or ST889, spa type t037, SCCmec type IIIA) was related to the Brazilian clone. 相似文献
87.
Alvarez-Manceñido Felipe Jimenez-Fonseca Paula Carmona-Bayonas Alberto Arrazubi Virginia Hernandez Raquel Cano Juana M. Custodio Ana Pericay Pijaume Carles Aguado Gema Martínez Lago Nieves Sánchez Cánovas Manuel Cacho Lavin Diego Visa Laura Martinez-Torron Alba Arias-Martinez Aranzazu López Flora Limón M. Luisa Vidal Tocino Rosario Fernández Montes Ana Alsina Maria Pimentel Paola Reguera Pablo Martín Carnicero Alfonso Ramchandani Avinash Granja Mónica Azkarate Aitor Martín Richard Marta Serra Olbia Hernández Pérez Carolina Hurtado Alicia Gil-Negrete Aitziber Sauri Tamara Morales del Burgo Patricia Gallego Javier 《Gastric cancer》2021,24(4):926-936
Gastric Cancer - Advanced esophageal adenocarcinoma (EAC) is generally treated similarly to advanced gastroesophageal junction (GEJ-AC) and gastric (GAC) adenocarcinomas, although GAC clinical... 相似文献
88.
Tung Gia Phan Juana del Valle Mendoza Mohammadreza Sadeghi Eda Altan Xutao Deng Eric Delwart 《Virus genes》2018,54(1):33-40
Serum samples collected from 88 Peruvians with unexplained fever were analyzed for viral sequences using metagenomics. Nucleic acids of anelloviruses, pegivirus A (GBV-C), HIV, Dengue virus, and Oropouche virus were detected. We also characterized from two sera the RNA genomes of new species of partitivirus and dicistrovirus belonging to viral families known to infect fungi or arthropod, respectively. Genomic DNA of a putative fungal cellular host could be PCR amplified from the partitivirus-containing serum sample. The detection in human serum of nucleic acids from viral families not known to infect vertebrates may indicate contamination during sample collection and aliquoting or human infection by their presumed cellular host, here a fungus. The role, if any, of the non-vertebrate infecting viruses detected in serum in inducing fever is unknown. 相似文献
89.
David Benaiges Antonio Más-Lorenzo Albert Goday José M Ramon Juan J Chillarón Juan Pedro-Botet Juana A Flores-Le Roux 《World journal of gastroenterology : WJG》2015,21(41):11804-11814
Sleeve gastrectomy(SG) is a restrictive bariatric surgery technique that was first used as part of restrictive horizontal gastrectomy in the original Scopinaro type biliopancreatic diversion. Its good results as a single technique have led to a rise in its use, and it is currently the second most performed technique worldwide. SG achieves clearly better results than other restrictive techniques and is comparable in some aspects to the Roux-en-Y gastric bypass, the current gold standard in bariatric surgery. These benefits have been associated with different pathophysiologic mechanisms unrelated to weight loss such as increased gastric emptying and intestinal transit, and activation of hormonal mechanisms such as increased GLP-1 hormone and decreased ghrelin. The aim of this review was to highlight the salient aspects of SG regarding its historical evolution, pathophysiologic mechanisms, main results, clinical applications and perioperative complications. 相似文献
90.
Vidriales MB Pérez JJ López-Berges MC Gutiérrez N Ciudad J Lucio P Vazquez L García-Sanz R del Cañizo MC Fernández-Calvo J Ramos F Rodríguez MJ Calmuntia MJ Porwith A Orfao A San-Miguel JF 《Blood》2003,101(12):4695-4700
Investigation of minimal residual disease (MRD) in acute leukemias by immunophenotyping and/or molecular techniques is proving to be increasingly valuable for disease monitoring. In acute lymphoblastic leukemia (ALL), most MRD studies have focused on children, whereas in contrast, information on the value of MRD on adult ALL is scanty, and almost exclusively restricted to polymerase chain reaction (PCR) studies. Early response to therapy is one of the most important prognostic factors in acute leukemia, which prompted us to investigate whether or not early immunophenotypic assessment of MRD could also be a valuable tool for predicting relapse in adult patients with ALL. For that purpose we have analyzed the level of MRD during the initial phase of treatment (induction phase) by multiparameter flow cytometry in a series of 102 adolescent (older than 14 years) and adult patients with ALL. Immunophenotypic evaluation of the bone marrow (BM) at day +35 showed that patients with low MRD levels (< 0.05% leukemia-associated phenotype [LAP+] cells) had a significantly longer relapse-free survival (RFS) than patients with high MRD levels, and this prognostic influence was retained when only those patients in morphologic complete remission (mCR) at day +35 were considered (median RFS: 42 months vs 16 months; P =.001). Moreover, immunophenotyping helped to identify a small subset of patients (n = 12) with negative or low MRD levels (< 0.03% LAP+ cells) by day +14, with an excellent prognosis (projected RFS of 90% at 5 years). The contrary is true of patients who achieved late mCR (after day +35), since immunophenotypic investigation of MRD showed that, in spite of the mCR, none of the cases with more than 0.1% LAP+ cells would be relapse-free after 2 years. Multivariate analysis showed that the immunologic evaluation of MRD at day +35 was the most relevant independent prognostic parameter for adult patients with ALL, and together with age, white blood cell (WBC) count at diagnosis, and presence of the Philadelphia (Ph) chromosome, represented the most informative combination of variables for predicting relapse-free survival. 相似文献