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81.
Sixty isolates of Mycobacterium tuberculosis identified as multidrug-resistant (MDR) at a reference laboratory in Rio Grande do Sul State during the years 1999 and 2000 were analyzed using the IS6110-restriction fragment length polymorphism (RFLP) technique. We also genotyped 202 susceptible strains to compare the genotyping results, as well as the clinical and demographic data. Spacer oligotyping (spoligotyping) analysis was performed for isolates presenting low IS6110 copy number. Patients with identical DNA pattern strains were considered clustered. From 262 isolates, 94 (36%) belonged to 20 distinct RFLP clusters, and after spoligotyping analysis, 89 of the isolates (34%) remained in cluster. MDR isolates did not differ statistically in clustering proportion from susceptible strains. A significant association between the occurrence of MDR and previous tuberculosis (TB) treatment was observed (p < 0.001), as well as failure on TB treatment (p < 0.001). Human immunodeficiency virus (HIV)-positive patients were associated with susceptible tuberculosis (p = 0.024). We also identified that unmarried patients were more likely to develop TB due to recent transmission than married patients (p < 0.005). The introduction of directly observed therapy short-course (DOTS) strategy will be important in decreasing default and failure rates and avoiding the development of new MDR strains.  相似文献   
82.
BACKGROUND: Clinical judgments about the likelihood of suicide attempt would be aided by an index of risk factors that could be quickly assessed in diverse settings. We sought to develop such a risk index for 12-month suicide attempts among suicide ideators. METHOD: The National Comorbidity Survey Replication (NCS-R), a household survey of adults aged 18+, assessed the 12-month occurrence of suicide ideation, plans and attempts in a subsample of 5692 respondents. Retrospectively assessed correlates include history of prior suicidality, sociodemographics, parental psychopathology and 12-month DSM-IV disorders. RESULTS: Twelve-month prevalence estimates of suicide ideation, plans and attempts are 2.6, 0.7 and 0.4% respectively. Although ideators with a plan are more likely to make an attempt (31.9%) than those without a plan (9.6%), 43% of attempts were described as unplanned. History of prior attempts is the strongest correlate of 12-month attempts. Other significant correlates include shorter duration of ideation, presence of a suicide plan, and several sociodemographic and parental psychopathology variables. Twelve-month disorders are not powerful correlates. A four-category summary index of correlates is strongly related to attempts among ideators [area under the receiver operator characteristic curve (AUC)=0.88]. The distribution (conditional probability of attempt) of the risk index is: 19.0% very low (0.0%), 51.1% low (3.5%), 16.2% intermediate (21.3%), and 13.7% high (78.1%). Two-thirds (67.1%) of attempts were made by ideators in the high-risk category. CONCLUSIONS: A short, preliminary risk index based on retrospectively reported responses to fully structured questions is strongly correlated with 12-month suicide attempts among ideators, with a high concentration of attempts among high-risk ideators.  相似文献   
83.
Early experiments have resulted in the establishment of an efficient methodology for the production of a yellow fever vaccine in chicken embryo fibroblasts (CEF) using the 17DD virus strain [Freire, M.S., Mann, G.F., Marchevsky, R.S., Yamamura, A.M., Almeida, L.F., Jabor, A.V., Malachias, J.M., Coutinho, E.S., Galler, R., 2005. Production of yellow fever 17DD vaccine virus in primary culture of chicken embryo fibroblasts: yields, thermo and genetic stability, attenuation and immunogenicity. Vaccine 23, 2501-2512]. To investigate the role of the interferon system in vaccine virus yields, CEF cultures seeded at high and low cell densities and infected with the yellow fever 17DD virus were used. The supernatants of these cultures were tested for the presence of interferon by an assay based on the reduction of cytopathic effect of a challenge virus (Sindbis), for the enzymatic activity of the interferon-induced 2',5'-oligoadenylate synthetase and for the expression of 2',5'-oligoadenylate synthetase mRNA. The presence of interferon and its influence in the replication of yellow fever 17DD virus in CEF cultures was clearly demonstrated.  相似文献   
84.
Fungal keratitis is recognized as a significant cause of ocular morbidity and blindness especially in developing countries. In this study, we aimed to present the molecular identification and susceptibility of Fusarium isolates causing fungal keratitis in a university hospital in southern Brazil. The samples were identified using the second largest subunit of the RNA polymerase gene (RPB2) and the translation elongation factor 1-alpha (TEF1), while the antifungal susceptibility was tested by the broth microdilution method according to the Clinical and Laboratory Standards Institute (CLSI) methodology. The majority of the isolates belonged to the Fusarium solani species complex (F. solani, F. keratoplasticum and F. falciforme) and Fusarium oxysporum species complex. Antifungal susceptibility has shown that amphotericin B and natamycin were the most effective antifungals across all isolates, followed by voriconazole. Variation among Fusarium complexes in their antifungal sensitivities was observed in our study. The identification of Fusarium species from human samples is important not only from an epidemiological viewpoint, but also for choosing the appropriate antifungal agent for difficult-to-treat Fusarium infections such as keratitis.  相似文献   
85.
Cardiac remodeling (CR) is a structural change of the heart due to chronic hemodynamic overload related to changes in both myocyte and extracellular matrix (ECM). We investigated that the imbalance of collagen V promotes cardiomyocyte apoptosis that contributes to heart failure and cell death. Aortic stenosis was induced surgically and male Wistar rats were randomized to 18 weeks (Sham 18?w, n?=?12; AoS 18?w, n?=?12) and severe of heart failure (Sham HF, n?=?12; AoS HF, n?=?12) groups. Functional and structural echocardiogram, immunohistochemistry for Ki-67, TUNEL assay and Immunofluorescence for collagen were performed. Our main results were: (1) Progressive reduction of cardiac functional capacity due to cardiac remodeling with decreased eject fraction in heart failure; (2) Imbalance of collagen deposition with increased, crowded and irregular collagen I in situ expression; (3) Dysregulation of dynamic control of collagen fibers with exposed epitopes of collagen V; (4) Additional apoptosis that are dependent to cardiac injury. The collagen V expression in cardiac remodeling is for the first time described and may be related to additional apoptosis and autoimmune response. Our findings suggest a critical role of collagen V in cardiac remodeling to modulate and promote heart failure and death.  相似文献   
86.
Fallopian tube (FT) and endometrial urocortin 1 (Ucn1) and corticotropin-releasing hormone (CRH)-receptor (CRH-R1/CRH-R2) expression were examined using quantitative real-time polymerase chain reaction (RT-PCR) and immunohistochemistry in nonpregnant and pregnant women (intrauterine, IUP; ectopic pregnancy, EP). Tubal Ucn1 messenger RNA (mRNA) expression was higher in luteal compared to follicular phase (P < .01) and equivalent to follicular phase in FT from EP. Tubal CRH-R1/CRH-R2 mRNA was lower in luteal phase (P < .05) and in FT from EP compared to follicular phase (P < .01). Ucn1 mRNA was lower in endometrium from EP compared to IUP (P < .05). Corticotropin-releasing hormone-R1 mRNA was higher in endometrium from EP compared to viable IUP (P < .05). No differences were observed in CRH-R2 expression. Corticotropin-releasing hormone-R1 protein was primarily localized to epithelium of FT and endometrium. Quantitative analysis of tubal CRH-R1 protein expression reflected that seen at the mRNA level but endometrial expression was equivocal. The demonstration of attenuated tubal/endometrial Ucn1/CRH-R expression in EP further supports a role of the CRH-family in embryo implantation.  相似文献   
87.
Melanomacrophages are the pigmented cells present in the hematopoietic organs. Besides melanin, hemosiderin and lipofuscin are also observed in the melanomacrophages. For the liver, however, numerous studies relate these cells to immunological and metabolic functions. Therefore, the aim of this study is to evaluate the hepatic metabolism by quantifying melanin, hemosiderin and lipofuscin in the anuran Eupemphix nattereri submitted to varying thermal conditions. E. nattereri adult males were separated into three groups, as follows: (i) five animals in the control group were kept at room temperature (27°C); (ii) 30 animals were submitted to hyperthermic (35.1°C); and (iii) 30 to hypothermic (18.9°) conditions. In each experiment, the animals were analyzed and separated into two different treatments: (1) immediately after undergoing the stress; and, (2) after recovering from the stress caused by the stimulus, at three distinct times (12 hr, 24 hr, and 48 hr). Both hyperthermia and hypothermia decreased hepatic pigmentation after thermal stress. The recovered animals of both experimental treatments showed as much pigmentation as the control animals. Thermal stress alters hemosiderin and lipofuscin as well, which may be related to liver function catabolism. In conclusion, liver pigmentation decreased due to temperature variation and duration of thermal stimulation to which the animals were exposed. The increase in temperature rather than hypothermia led to more drastic physiological disorders. In this study, we observed that thermal stress for a short period compromises the morphology and liver function, as observed by the changing pigmentation of melanomacrophages. These analyses can be used as biomarkers of environmental effects. Anat Rec, 297:864–875, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
88.
The trematode Schistosoma mansoni, an important parasite of humans, is the principle agent of the disease schistosomiasis. In the human host, one of the most important stress factors of this parasite is the oxidative stress generated by both the metabolism of the worm and the immune system of the host. The proteasomal system is responsible for protein homeostasis during oxidative stress. The 26S proteasome is a multicatalytic protease formed by two compartments, a 20S core and regulatory particle 19S, and controls the degradation of intracellular proteins, hence regulating many cellular processes. In the present report, we describe the biochemical characterization and role of the 20S proteasome in the response of adult S. mansoni worms exposed to hydrogen peroxide. Characterization of the response to the oxidative stress included the evaluation of viability, egg production, mortality, tegument integrity, and both expression and activity of proteasome. We observed decreases in viability, egg production as well as 100 % mortality at the higher concentrations of hydrogen peroxide tested. The main changes observed in the tegument of adult worms were peeling as well as the appearance of bubbles and a decrease of spines on the tubercles. Furthermore, there were increases in 26S activity to the same extent as 20S proteasome activity, although there was increase of 20S proteasome content, suggesting that degradation of protein oxidized in adult worms is due to the 20S proteasome. It was demonstrated that adult S. mansoni worms are sensitive to oxidative stress, and that a variety of processes in this parasite are altered under this condition. The work contributes to a better understanding of the mechanisms employed by S. mansoni to survive under oxidative stress.  相似文献   
89.

OBJECTIVES:

Atrial fibrillation is the most common sustained arrhythmia and is associated with poor outcomes, including stroke. The ability of anticoagulation therapy to reduce the risk of stroke has been well established; however, the prevalence of anticoagulation therapy use in the Public Health System is unknown. The aim of this study is to evaluate both the prevalence of anticoagulation therapy among patients with atrial fibrillation and the indications for the treatment.

METHODS:

In this cross-sectional study, we included consecutive patients who had atrial fibrillation documented by an electrocardiogram performed between September 2011 and March 2012 at a university hospital of the Public Health System. The variables analyzed included the risk of a thromboembolic event and/or bleeding, the use of antiplatelet or anticoagulation therapy, the location where the electrocardiogram report was initially reviewed and the specialty of the physician who initially reviewed it.

RESULTS:

We included 162 patients (mean age 68.9 years, 56% men). Hypertension (90.1%), heart failure (53.4%) and stroke (38.9%) were the most prevalent diseases found. Only 50.6% of the patients knew that they had atrial fibrillation. Regarding the use of therapy, only 37.6% of patients classified as high risk according to the CHADS2 scores and 35.5% according to the CHA2DS2VASc used oral anticoagulation. A presumptive diagnosis of heart failure and the fact that the electrocardiogram was evaluated by a cardiologist were the only independent predictors of the use of anticoagulants.

CONCLUSIONS:

Our study found a low prevalence of oral anticoagulation therapy among patients with atrial fibrillation and an indication for stroke prophylaxis for the use of this therapy, including among those with high CHADS2 and CHA2DS2VASc scores.  相似文献   
90.
Objective: To present a case of an early treatment of cardiac intraperitoneal teratoma (IPT) in a newborn and its associated systematic literature review.

Methods: We presented a case of a newborn with IPT but without hydrops and having a good perinatal outcome after cardiac surgery. Using the PubMed database, we conducted a systematic literature review of articles regarding cases with cardiac IPT diagnosed and treated in the neonatal period and published in English from 2004 onward. We excluded cases that involved fetal death or interrupted gestation events.

Results: In total, 38 cases of IPT from 31 articles were included. The mean?±?standard deviation of the gestational age at diagnosis and delivery were 27.9?±?5.7 and 33.0?±?3.5 weeks, respectively, and that of birth weight was 2373?±?834.5?g. The majority of fetuses (42.1%) were males. Pericardial effusion was the most common symptom (60.5%) followed by hydrops (42.1%) and respiratory distress (42.1%). Intrauterine procedure was not performed in 63.1% of cases, and 71.0% of newborns were alive.

Conclusions: IPT in newborns is usually associated with a good prognosis without the need for intrauterine procedures. Cases with IPT-related death are associated with hemodynamic impairment in fetuses with hydrops.  相似文献   
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