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991.
Strains of the Beijing genotype family of Mycobacterium tuberculosis are a cause of particular concern because of their increasing dissemination in the world and their association with drug resistance. Phylogenetically, this family includes distinct ancient and modern sublineages. The modern strains, contrary to the ancestral counterparts, demonstrated increasing prevalence in many world regions that suggest an enhanced bacterial pathogenicity. We therefore evaluated virulence of modern versus ancient Beijing strains with similar epidemiological and genotype characteristics. For this, we selected six strains that had very similar 24-locus mycobacterial interspersed repetitive-unit–variable-number tandem-repeat (MIRU-VNTR) typing profiles and belonged to the region of difference 181 (RD181) subgroup but differed using markers (mutT2 and mutT4 genes and NTF locus) that discriminate between modern and ancient Beijing sublineages. The strains were isolated from native patients in Brazil and Mozambique, countries with a low prevalence of Beijing strains. The virulence levels of these strains were determined in models of pulmonary infection in mice and in vitro macrophage infection and compared with that of a strain from Russia, part of the epidemic and hypervirulent Beijing clone B0/W148, and of the laboratory strain H37Rv. The results showed that two of the three modern Beijing strains were highly pathogenic, exhibiting levels of virulence comparable with that of the epidemic Russian strain. In contrast, all isolates of the ancient sublineage displayed intermediate or low virulence. The data obtained demonstrate that the strains of the modern Beijing sublineage are more likely to exhibit highly virulent phenotypes than ancient strains and suggest that genetic alterations characteristic of the modern Beijing sublineage favor selection of highly virulent bacteria.  相似文献   
992.
993.
Prion protein gene mutations have been associated with clinical pictures mimicking neurodegenerative diseases different from inherited prion diseases (IPD). We report a novel missense P39L mutation in the N-terminal domain of prion protein in 2 patients affected by frontotemporal lobar degeneration syndrome, negative for mutations in genes causative of dementia. Neither the first carrier, a 67-year-old male in which the onset was a progressive non-fluent aphasia, nor the second carrier, a 78-year-old male affected by frontotemporal dementia and parkinsonism, showed any clinical or instrumental findings suggestive of IPD. Genetic screening of healthy controls and in silico analysis provide support for the potential pathogenicity of this variant. Patient phenotypes, unclassifiable as prion disease, may depend on the location of the mutation in the N-terminal domain, outside the amyloid core of pathologic prion protein, although further functional studies are required to determine whether and how this mutation exerts its pathogenic effect. However, genetic screening of prion protein gene becomes relevant in familial degenerative dementia, particularly in geographical areas with high IPD prevalence.  相似文献   
994.
The aim of this study was to identify and associate the sequence variations of human Papillomavirus 16 (HPV16) genes from women who live in two different areas of Romania and associate them with malignant progression. One hundred twenty-four HPV16-positive cervical isolates were collected, and the E2, E4, E5, E6 and E7 viral genes were sequenced. Two new missense mutations in the E6 gene (C279G and A305C) were found (together or alone, in association with other mutations) in 44 of 124 cases. The most frequently simultaneously mutated genes were E4/E2 hinge, E5 and E6 (p = 0.0004) in squamous cell carcinoma (SCC) samples. Also, for SCC patients, the best-correlated mutation patterns were obtained for E4/E2 hinge-E5 (r = 0.7984; p < 0.0001). No sample was found to have all of the investigated viral genes concurrently mutated. Phylogenetic analysis was performed to characterize the viral variants. Similar results were found for SCC and cervical intraepithelial neoplasia III (CINIII) cases. After all of the target gene sequences were assembled, all patients were found to be infected with viruses of the HPV16- European-German (EG) lineage, and two clusters were identified, the first (55/96 variants) from Moldavia and the second (41/96 variants) from Bucharest. The distinct cluster derived from EG in Moldavia could partially explain the increased frequency of SCC in this area. This study has generated a comprehensive set of sequence variation data on HPV16 circulating in Romania to join the existing data and highlight the important role of HPV16 variants during cervical carcinogenesis.  相似文献   
995.
Primary immunodeficiencies are intrinsic defects in the immune system that result in a predisposition to infection and are frequently accompanied by a propensity to autoimmunity and/or immunedysregulation. Primary immunodeficiencies can be divided into innate immunodeficiencies, phagocytic deficiencies, complement deficiencies, disorders of T cells and B cells (combined immunodeficiencies), antibody deficiencies and immunodeficiencies associated with syndromes. Diseases of immune dysregulation and autoinflammatory disorder are many times also included although the immunodeficiency in these disorders are often secondary to the autoimmunity or immune dysregulation and/or secondary immunosuppression used to control these disorders. Congenital primary immunodeficiencies typically manifest early in life although delayed onset are increasingly recognized. The early diagnosis of congenital immunodeficiencies is essential for optimal management and improved outcomes. In this International Consensus (ICON) document, we provide the salient features of the most common congenital immunodeficiencies.  相似文献   
996.
This study aims to evaluate the effects of an angiotensin receptor blocker (ARB)/calcium channel blocker combination on blood pressure control, lipid profile, insulin sensitivity, and inflammation markers. We randomized 276 hypertensive patients to olmesartan 20 mg, amlodipine 10 mg, or a single pill containing an olmesartan/amlodipine combination 20/5 mg for 12 months. We evaluated the following: body weight, systolic and diastolic blood pressure, fasting plasma glucose, fasting plasma insulin (FPI), M value, lipid profile, adiponectin (ADN), high sensitivity C-reactive protein (Hs-CRP), monocyte chemoattractant protein-1 (MCP-1), and macrophage migration inhibitory factor-1β (MIP-1β). Olmesartan/amlodipine combination better reduced blood pressure, FPI, homeostasis model assessment index, and increased M value and ADN compared to olmesartan and amlodipine monotherapies. Olmesartan/amlodipine significantly decreased Hs-CRP, MCP-1, and MIP-1β. In this multicenter, randomized, double-blind, clinical study, ARB/calcium antagonist combination resulted to be more effective than single monotherapies in reducing blood pressure, in improving insulin sensitivity, and in reducing inflammation parameters in patients with stage I essential hypertension.  相似文献   
997.
The aim of this work was to study the relationship between dietary total antioxidant capacity (TAC) and current asthma in a group of Spanish schoolchildren. A total of 78 Spanish schoolchildren (26 asthmatic and 52 healthy controls) were randomly selected from a cohort of 564 children (9–12 years of age). The weight and height of all subjects were recorded. A questionnaire, completed by the subjects' parents, was used to obtain personal and health information. Current asthma was established when children had ever had asthma, they had been diagnosed with asthma by a physician, and they had been treated with medications at some time in the previous 12 months. Food intake was monitored using a 3-day food record. All consumed foods were converted into energy and nutrients. Dietary TAC was evaluated using the ferric reducing antioxidant power (FRAP), radical-trapping antioxidant parameter (TRAP), and Trolox equivalent antioxidant capacity (TEAC) assays. The TAC measured using all the assays was significantly lower in children with asthma than in children without this condition (2.95 (2.10–3.75)?mmol Fe(II)/day vs. 3.70 (3.08–4.49)?mmol Fe(II)/day, p?<?0.01; 1.50 (1.06–2.05)?mmol Trolox equivalents/day vs. 2.10 (1.40–2.65)?mmol Trolox equivalents/day, p?<?0.05; and 1.60 (1.08–2.00)?mmol Trolox equivalents/day vs. 1.85 (1.50–2.68)?mmol Trolox equivalents/day, p?<?0.05 for FRAP, TEAC, and TRAP, respectively). After adjusting for energy intake, children with FRAP values higher than 3.5 mmol Fe(II)/day (p50) and TEAC values higher than 1.9 mmol Trolox equivalents/day (p50) had 22.6 and 35.0 %, respectively, lower likelihood of suffering asthma episodes than children with lower values. When logistic regression analysis was performed separately for children with nonsmoker and smoker (at least one) parents, the association between dietary TAC and asthma was only observed in the nonsmoker group (OR?=?0.257, 95 % CI?=?0.107–0.618, p?=?0.002 for FRAP; OR?=?0.212, 95 % CI?=?0.069–0.639, p?=?0.006 for TEAC; and OR?=?0.264, 95 % CI?=?0.091–0.769, p?=?0.015 for TRAP assay). Conclusion: Dietary TAC may have a favorable role in asthma in children and, specially, in those with nonsmoker parents.  相似文献   
998.

Objectives

Mechanical loading is a potential activator of inflammation and able to stimulate factors for periodontal and alveolar bone destruction. Aim of this study was to investigate the inflammatory response and synthesis of proteinases by human periodontal ligament fibroblast (HPdLF) dependent on different strengths of static tensile strain (STS).

Materials and methods

HPdLFs were loaded with different STS strengths (1, 5, and 10 %) in vitro. Gene expressions of cyclooxygenase (COX)-2 and interleukin (IL)-6 were analyzed by quantitative real-time polymerase chain reaction. Production of IL-6, prostaglandin E2 (PGE2), matrix metalloproteinase (MMP)-8, and tissue inhibitors of matrix metalloproteinase (TIMP)-1 were measured by enzyme-linked immunosorbent assay. Receptor activator of nuclear factor-kappa ligand (RANKL) synthesis was detected by immunocytochemical staining.

Results

Ten percent STS led to an increased gene expression of IL-6 and COX-2 (34.4-fold) in HPdLF, and 1 and 5 % STS slightly reduced the gene expression of IL-6. Synthesis of IL-6 was significantly reduced by 1 % STS and stimulated by 10 % STS. Ten percent STS significantly induced PGE2 production. RANKL was not detectable at any strength of STS. MMP-8 synthesis showed significantly higher values only at 10 % STS, but TIMP-1 was stimulated by 5 and 10 % STS, resulting into highest TIMP-1/MMP-8 ratio at 5 % STS.

Conclusions

High-strength STS is a potent inducer of periodontal inflammation and MMP-8, whereas low-strength STS shows an anti-inflammatory effect. Moderate-strength STS causes the highest TIMP-1/MMP-8 ratio, leading to appropriate conditions for reformation of the extracellular matrix.

Clinical relevance

Furthermore, this study points out that the strength of force plays a pivotal role to achieve orthodontic tooth movement without inducing periodontal inflammation and to activate extracellular matrix regeneration.  相似文献   
999.
Introduction: The effort to increase patient safety has become one of the main focal points of all health care professions, despite the fact that, in the field of dentistry, initiatives have come late and been less ambitious. The main objective of patient safety is to avoid preventable adverse events to the greatest extent possible and to limit the negative consequences of those which are unpreventable. Therefore, it is essential to ascertain what adverse events occur in each dental care activity in order to study them in-depth and propose measures for prevention. Objectives: To ascertain the characteristics of the adverse events which originate from dental care, to classify them in accordance with type and origin, to determine their causes and consequences, and to detect the factors which facilitated their occurrence. Material and Methods: This study includes the general data from the series of adverse dental vents of the Spanish Observatory for Dental Patient Safety (OESPO) after the study and analysis of 4,149 legal claims (both in and out of court) based on dental malpractice from the years of 2000 to 2010 in Spain. Results: Implant treatments, endodontics and oral surgery display the highest frequencies of adverse events in this series (25.5%, 20.7% and 20.4% respectively). Likewise, according to the results, up to 44.3% of the adverse events which took place were due to predictable and preventable errors and complications. Conclusions: A very significant percentage were due to foreseeable and preventable errors and complications that should not have occurred. Key words:Patient safety, adverse event, medical care risk, dentistry.  相似文献   
1000.
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