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111.
Dulciene Maria de Magalhães Queiroz Roberto Penna de Almeida Cunha Ivan Euclides Borges Saraiva 《Toxicon》2010,56(7):1193-1197
Helicobacter pylori is one of the most common infections worldwide. In most individuals it consists in a lifelong host-pathogen relationship without consequences, but in some subjects it is associated with peptic ulcer disease and gastric cancer. Polymorphism in genes that code bacterial virulence factors, cagA and vacA, are independently associated with the infection severe outcomes and are geographically diverse. In the last decade, accumulated knowledge allowed to characterize typical H. pylori strain patterns for all the major human populations; patterns that can be used to study the origin of specific human groups. Thus, the presence or absence of cagA, cagA EPIYA genotypes, and vacA subtypes can be used as tools to study not only the geographic origin of specific human populations, but also to identify markers of historical contact between different ethnicities. We report here a study including a set of native Amazon Amerindians that had supposedly been some, but little, contact with European Brazilian colonizer and/or African slaves. They harbor H. pylori strains in a mixed pattern with Asian and Iberian Peninsula characteristics. It is possible that this finding represents H. pylori recombination upon short contact between human groups. Alternatively, it could be due to a founder effect from a small cluster of Asian origin native Americans. 相似文献
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113.
Immunosuppressive and anti-inflammatory agents are able to generate tolerogenic DCs, leading, in some cases, to induction or enhancement of regulatory T cells with suppressive activity. This novel mechanism of action, shared by several immunosuppressive and anti-inflammatory agents, is becoming firmly established and contributes to explain their functional properties. The possibility to manipulate DCs in vivo using more or less conventional low molecular weight drugs, enabling them to exert tolerogenic activities, could be exploited to better control a variety of chronic inflammatory conditions, from autoimmune diseases to allograft rejection. 相似文献
114.
I Portoghese M Galletta A Battistelli L Saiani MP Penna E Allegrini 《Journal of nursing management》2012,20(5):582-591
portoghese i., galletta m., battistelli a., saiani l., penna m.p. & allegrini e. (2012) Journal of Nursing Management 20, 582–591 Change-related expectations and commitment to change of nurses: the role of leadership and communication Aim The purpose of this study was to test a theoretical model linking the impact of expectations on commitment to change and to explore whether change-related communication is a mediating variable between leader–member exchange and expectations. Background Expectations for change outcomes are an important condition to increase nurses’ commitment to change. To understand the role of leadership and communication in expectations development is crucial to promote commitment to change. Method A predictive, non-experimental design was used in a random sample of 395 nurses. Structural equation modelling was used to analyse the hypothesized model. Results Positive expectations had a direct effect on affective commitment to change, whereas negative expectation had a direct effect on continuance commitment to change. Leader–member exchange and communication influenced nurse’s expectations about change. Communication partially mediated the relationship between Leader–member exchange and expectations. Conclusion These findings suggested that nurses’ expectation about change were strongly linked to commitment to change. Furthermore, the enhancement of communication and relationship with leader contributed to the development of positive and negative expectations. Implications for nursing management Strategies to promote commitment to change include developing positive expectations about change outcomes and building high-quality leadership style oriented to the communication. 相似文献
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116.
Rodrigo Scaliante Moura Gerson Oliveira Penna Ludimila Paula Vaz Cardoso Maria Araci de Andrade Pontes Rossilene Cruz Heitor de Sá Gon?alves Maria Lúcia Fernandes Penna Mariane Martins de Araújo Stefani Samira Bührer-Sékula 《The American journal of tropical medicine and hygiene》2015,92(6):1280-1284
The uniform multidrug therapy clinical trial, Brazil (U-MDT/CT-BR), database was used to describe and report the performance of available tools to classify 830 leprosy patients as paucibacillary (PB) and multibacillary (MB) at baseline. In a modified Ridley and Jopling (R&J) classification, considering clinical features, histopathological results of skin biopsies and the slit-skin smear bacterial load results were used as the gold standard method for classification. Anti-phenolic glycolipid-I (PGL-I) serology by ML Flow test, the slit skin smear bacterial load, and the number of skin lesions were evaluated. Considering the R&J classification system as gold standard, ML Flow tests correctly allocated 70% patients in the PB group and 87% in the MB group. The classification based on counting the number of skin lesions correctly allocated 46% PB patients and 99% MB leprosy cases. Slit skin smears properly classified 91% and 97% of PB and MB patients, respectively. Based on U-MDT/CT-BR results, classification of leprosy patients for treatment purposes is unnecessary because it does not impact clinical and laboratories outcomes. In this context, the identification of new biomarkers to detect patients at a higher risk to develop leprosy reactions or relapse remains an important research challenge. 相似文献
117.
Christophe Penna M.D. Emmanuel Tiret M.D. Frederic Daude M.D. Professor Rolland Parc M.D. 《Diseases of the colon and rectum》1994,37(2):157-160
PURPOSE: Rectal cancer frequently occurs in patients with familial adenomatous polyposis (FAP) and, in some cases, proctocolectomy and ileal pouch-anal anastomosis (IPAA) can be proposed as an alternative to end ileostomy. This study aimed to assess the results of IPAA for familial adenomatous polyposis complicated by rectal carcinoma. PATIENTS AND METHODS: Postoperative morbidity and bowel function following IPAA were assessed in six patients who had a mesorectal excision for rectal cancer. The functional results were compared with those obtained after IPAA in 134 FAP patients without bowel cancer. RESULTS: Carcinomas were located at a mean of 11 cm from the dentate line. There were no postoperative complications. One patient with synchronous hepatic metastases died 6 months after operation and the 5 others were alive without recurrence after a mean follow-up of 29 months. Mean frequency of defecation was 6.5/day (vs. 4.2/day in patients without carcinoma), 86 percent of patients had nocturnal defecation (vs. 50 percent), day and night continence were normal in 66 percent and 33 percent of patients, respectively, compared with 90 percent and 85 percent for IPAA without cancer. Pouch excision was required in one patient for unsatisfactory functional result. CONCLUSION: IPAA can be safely performed for cancer of the upper rectum complicating FAP, but a poor functional outcome related to mesorectal excision has to be expected. 相似文献
118.
HLA class I-restricted human cytotoxic T cells recognize endogenously synthesized hepatitis B virus nucleocapsid antigen. 总被引:30,自引:1,他引:30 下载免费PDF全文
A Bertoletti C Ferrari F Fiaccadori A Penna R Margolskee H J Schlicht P Fowler S Guilhot F V Chisari 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(23):10445-10449
Knowledge of the immune effector mechanisms responsible for clearance of hepatitis B virus (HBV)-infected cells has been severely limited by the absence of reproducible systems to selectively expand and to characterize HBV-specific cytotoxic T lymphocytes (CTLs) in the peripheral blood of patients with viral hepatitis. By using a strategy involving sequential stimulation with HBV nucleocapsid synthetic peptides followed by autologous, or HLA class I-matched, HBV nucleocapsid transfectants, we now report the existence of CTLs able to lyse target cells that express endogenously synthesized HBV nucleocapsid antigen in the peripheral blood of patients with acute viral hepatitis B. The CTL response is HLA-A2 restricted, mediated by CD8-positive T cells, and specific for a single epitope, located between amino acid residues 11 and 27 of HBV core protein; these residues are shared with the secretable precore-derived hepatitis B e antigen. Equivalent lysis of target cells that express each of these proteins suggests that their intracellular trafficking pathways may intersect. The current report provides definitive evidence that HLA class I-restricted, CD8-positive CTLs that recognize endogenously synthesized HBV nucleocapsid antigen are induced during acute HBV infection in humans and establishes a strategy that should permit a detailed analysis of the role played by HBV-specific CTLs in the immunopathogenesis of viral hepatitis. 相似文献
119.
Fujimura MD Koch VH Vaisbich MH Furusawa EA Schvartzmann BG Pozzi RA Saldanha LB Penna DO Okay Y 《Jornal de pediatria》1998,74(2):119-124
OBJECTIVE: To evaluate the diagnostic frequency of the various diseases associated with the development of hematuria in children, in a pediatric nephrology unit pertaining to a university hospital. METHODS: The clinical records of 128 children (70 male, 50 female) who presented intermittent/persistent macroscopic hematuria or persistent microscopic hematuria as the chief clinical complaint/finding, in the period of 1978-1995, were retrospectively analyzed. This evaluation was performed with special attention to the patientacute;s clinical history, physical examination, personal and family morbid history information. Patients whose investigation was not complete were not considered for analysis. The mean age on presentation was 8.2 years (5 months - 16 years) and the mean period of observation was 3.2 years (1 month-15 years). RESULTS: Macroscopic hematuria occurred in 104 patients and persistent microscopic hematuria was present in 24 patients. Urinary metabolic disturbances and urinary lithiasis, alone or in association, were diagnosed in the majority of the patients (65.5%). Hypercalciuria was the urinary metabolic disturbance (90.1%) mostly detected, either alone (73.2%) or in association with hyperuricosuria (16.9%). A positive family history of lithiasis was reported in 32.1% of the patients in which the diagnosis of lithiasis/urinary metabolic disturbance was confirmed. Glomerulopathies were diagnosed in 25% of the patients, with the predominance of post-infectious acute glomerulonephritis (11 patients, 34%). In 6 children, the etiology of hematuria was not elucidated, despite extensive investigation, including renal biopsy.CONCLUSION: The authors present an algorithm for the diagnosis of hematuria in children and suggest that in cases of isolated hematuria, presenting without clinical clues to the possible etiology, laboratory investigation should be started with the evaluation of urinary metabolic disturbances / lithiasis. 相似文献
120.
Oliveira MC Reis FJ Chagas AJ Brasileiro Filho G Bahia M Silva LD Penna FJ 《Jornal de pediatria》1998,74(3):213-216
OBJECTIVE: This study was carried out in order to evaluate the etiology of monosymptomatic childhood short stature (below the third percentile or with growth rate of less than 5 cm/year) with emphasis on causes due to intestinal malabsorption. METHODS: Each patient was submitted to endocrinological, biochemical and hematological investigation. Determination of serum anti-gliadin antibodies, fecal fat, chloride levels in sweat, jejunal biopsy and bone age was also obtained.RESULTS: A total of 51 children was studied, most of them belonging to the group of normal variants. Four children had abnormally high sweat chloride, compatible with the diagnosis of cystic fibrosis. These children were asymptomatic regarding respiratory and gastrointestinal tract. CONCLUSIONS: We conclude that cystic fibrosis, besides celiac disease, must be included in the differential diagnosis of short stature in childhood. 相似文献