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991.
Luciano Pamplona de Góes Cavalcanti Lia Alves Martins Mota Gustavo Porto Lustosa Mayara Carvalho Fortes Davi Alves Martins Mota Ant?nio Afonso Bezerra Lima Ivo Castelo Branco Coelho Maria Paula Gomes Mour?o 《Memórias do Instituto Oswaldo Cruz》2014,109(1):93-98
In 2009, the World Health Organization (WHO) issued a new guideline that stratifies
dengue-affected patients into severe (SD) and non-severe dengue (NSD) (with or
without warning signs). To evaluate the new recommendations, we completed a
retrospective cross-sectional study of the dengue haemorrhagic fever (DHF) cases
reported during an outbreak in 2011 in northeastern Brazil. We investigated 84
suspected DHF patients, including 45 (53.6%) males and 39 (46.4%) females. The ages
of the patients ranged from five-83 years and the median age was 29. According to the
DHF/dengue shock syndrome classification, 53 (63.1%) patients were classified as
having dengue fever and 31 (36.9%) as having DHF. According to the 2009 WHO
classification, 32 (38.1%) patients were grouped as having NSD [4 (4.8%) without
warning signs and 28 (33.3%) with warning signs] and 52 (61.9%) as having SD. A
better performance of the revised classification in the detection of severe clinical
manifestations allows for an improved detection of patients with SD and may reduce
deaths. The revised classification will not only facilitate effective screening and
patient management, but will also enable the collection of standardised surveillance
data for future epidemiological and clinical studies. 相似文献
992.
Alexandre Grangeiro Maria Mercedes Escuder Alex Jones Flores Cassanote Rosa Alencar Souza Artur O. Kalichman Valdiléa Veloso Maria Letícia Rodrigues Ikeda Nêmora Tregnago Barcellos Carlos Brites Unai Tupinanbás Noaldo O. Lucena Carlos Lima da Silva Heloisa Ramos Lacerda Beatriz Grinsztejn Euclides Ayres Castilho 《PloS one》2014,9(5)
Background
The HIV-Brazil Cohort Study was established to analyze the effectiveness of combination antiretroviral therapy (cART) and the impact of this treatment on morbidity, quality of life (QOL) and mortality. The study design, patients’ profiles and characteristics of cART initiation between 2003 and 2010 were described.Methodology/Principal Findings
Since 2003, the HIV-Brazil Cohort has been following HIV-infected adults receiving cART at 26 public health care facilities, using routine clinical care data and self-reported QOL questionnaires. When not otherwise available, data are obtained from national information systems. The main outcomes of interest are diseases related or unrelated to HIV; suppression of viral replication; adverse events; virological, clinical and immunological failures; changes in the cART; and mortality. For the 5,061 patients who started cART between 2003 and 2010, the median follow-up time was 4.1 years (IQR 2.2–5.9 years) with an 83.4% retention rate. Patient profiles were characterized by a predominance of men (male/female ratio 1.7∶1), with a mean age of 36.9 years (SD 9.9 years); 55.2% had been infected with HIV via heterosexual contact. The majority of patients (53.4%) initiated cART with a CD4+ T-cell count ≤200 cells/mm3. The medications most often used in the various treatment regimens were efavirenz (59.7%) and lopinavir/ritonavir (18.2%). The proportion of individuals achieving viral suppression within the first 12 months of cART use was 77.4% (95% CI 76.1–78.6). Nearly half (45.4%) of the patients presented HIV-related clinical manifestations after starting cART, and the AIDS mortality rate was 13.9 per 1,000 person-years.Conclusions/Significance
Results from cART use in the daily practice of health services remain relatively unknown in low- and middle-income countries, and studies with the characteristics of the HIV-Brazil Cohort contribute to minimizing these shortcomings, given its scope and patient profile, which is similar to that of the AIDS epidemic in the country. 相似文献993.
Paul J. Feldblum Sónia Enosse Karine Dubé Paulo Arnaldo Chadreque Muluana Reginaldo Banze Aristides Nhanala Joana Cunaca Pai-Lien Chen Merlin L. Robb Ricardo Thompson 《PloS one》2014,9(5)
Background
Reliable HIV incidence estimates for Mozambique are limited. We conducted a prospective HIV incidence study as part of a clinical research site development initiative in Chókwè district, Gaza Province, southern Mozambique.Methods
Between June 2010 and October 2012, we recruited women at sites where women at higher risk of HIV infection would likely be found. We enrolled and tested 1,429 sexually active women in the screening phase and 479 uninfected women in the prospective phase. Participants were scheduled for 12+ months follow-up, when they underwent face-to-face interviews, HIV counseling and testing, and pregnancy testing. We observed a total of 373.1 woman-years (WY) of follow-up, with mean (median) of 9.4 (9.7) women-months per participant.Results
The prevalence of HIV was 29.4% (95% confidence interval [CI]: 27.0–31.8%). In multivariable logistic regression analysis, factors that remained significantly associated with prevalent HIV were: older age (OR: 0.6; 95% CI: 0.4–0.7), lower educational level (OR: 0.4; 95% CI: 0.3–0.7), and using hormonal contraception (OR: 0.6; 95% CI: 0.4–0.7) or condoms (OR: 0.5; 95% CI: 0.3–0.7). We observed an HIV incidence rate of 4.6 per 100 WY (95% CI: 2.7, 7.3). The HIV incidence was 4.8 per 100 WY (95% CI: 2.5, 8.3) in women aged 18–24 years, 4.5 per 100 WY (95% CI: 1.2, 11.4) in women aged 25–29 years and 3.2 per 100 WY (95% CI: 0.1, 18.0) in the 30–35 years stratum. None of the demographic factors or time-varying behavioral factors examined was significantly associated with incident HIV infection in bivariable analysis at p≤0.10.Conclusions
We found a high HIV incidence among sexually active young women in Chókwè, Mozambique. HIV prevention programs should be strengthened in the area, with more comprehensive reproductive health services, regular HIV testing, condom promotion, and messaging about multiple sexual partners. 相似文献994.
Cristiana Leite N. Tatiana Silva Sandrine Mendes Andreia Ribeiro Joana Paes de Faria Tania Louren?o Francisco dos Santos Pedro Z. Andrade Carla M. P. Cardoso Margarida Vieira Artur Paiva Cláudia L. da Silva Joaquim M. S. Cabral Jo?o B. Relvas Mário Gr?os 《PloS one》2014,9(10)
Mesenchymal stem cells (MSCs) are viewed as safe, readily available and promising adult stem cells, which are currently used in several clinical trials. Additionally, their soluble-factor secretion and multi-lineage differentiation capacities place MSCs in the forefront of stem cell types with expected near-future clinical applications. In the present work MSCs were isolated from the umbilical cord matrix (Wharton''s jelly) of human umbilical cord samples. The cells were thoroughly characterized and confirmed as bona-fide MSCs, presenting in vitro low generation time, high proliferative and colony-forming unit-fibroblast (CFU-F) capacity, typical MSC immunophenotype and osteogenic, chondrogenic and adipogenic differentiation capacity. The cells were additionally subjected to an oligodendroglial-oriented step-wise differentiation protocol in order to test their neural- and oligodendroglial-like differentiation capacity. The results confirmed the neural-like plasticity of MSCs, and suggested that the cells presented an oligodendroglial-like phenotype throughout the differentiation protocol, in several aspects sharing characteristics common to those of bona-fide oligodendrocyte precursor cells and differentiated oligodendrocytes. 相似文献
995.
996.
Summary. We present the results of ultrastructural and immunocytochemical studies of sugar beet microsporocytes during the developmental
phase that begins with the first meiotic metaphase and ends with the formation of young tetrads. The most prominent feature
noted during this period of microsporogenesis was the presence of numerous cisternae of endoplasmic reticulum which frequently
lie perpendicular to the surface of the plasma membrane and eventually fuse to it. Microscopic observations have been combined
with the detection of several carbohydrate epitopes representing pectins and arabinogalactan proteins in the primexine and
incipient exine. Pectin domains that possess both low and highly methylesterified epitopes, as well as pectin side chains
enriched in (1→4)-β-D-galactose residues, are deposited in this young microspore wall. The epitopes of arabinogalactan protein
that bind to JIM13, JIM8, and LM2 antibodies are localised within the callose wall surrounding posttelophase tetrads. The
possibility of endoplasmic-reticulum involvement in the synthesis, transport, or metabolism of several microspore wall compounds
is discussed.
Correspondence and reprints: Institute of Plant Breeding and Acclimatization, Powstańców Wielkopolskich 10, 85-090 Bydgoszcz,
Poland. 相似文献
997.
The effect of the polychaete Nereis diversicolor on the stability of natural cohesive sediments was investigated in the laboratory. Three densities (450, 600 and 1200 ind m−2) of N. diversicolor were used. Sediment shear strength was measured using a cone penetrometer. Sediment erodability was assessed using an annular flume (current velocities from 5 to 55 cm s−1) in which flow velocity was increased incrementally, and water sampled to quantify suspended material in order to derive critical erosion velocity and erosion rates. At low current velocities ( <25 cm s−1), we found N. diversicolor to have a stabilising effect, reflected by an increase of up to 20% in the critical erosion velocity. This is related to an enhancement of ~50% in shear strength, due probably to gallery building activities, responsible for the promotion of lateral compaction, an increase in the area of the sediment–water interface, and enhanced microphytobenthos production. Once the sediment began to erode, the stabilising effect of N. diversicolor reverses, leading to an increase of up to 40% in eroded matter due to compaction, which resulted in the erosion of larger aggregates. The balance between the effect of N. diversicolor on herbivory and microphytobenthos production due to the presence of galleries is discussed. Our results indicate that neither chlorophyll a, nor shear strength nor critical erosion velocity are good indicators of erodability. This underlines the need to include biogeochemical processes in any realistic sediment transport model. 相似文献
998.
Rupert CM Jones Maria Dickson-Spillmann Martin JC Mather Dawn Marks Bryanie S Shackell 《Respiratory research》2008,9(1):62
Background
Guidelines on COPD diagnosis and management encourage primary care physicians to detect the disease at an early stage and to treat patients according to their condition and needs. Problems in guideline implementation include difficulties in diagnosis, using spirometry and the disputed role of reversibility testing. These lead to inaccurate diagnostic registers and inadequacy of administered treatments. This study represents an audit of COPD diagnosis and management in primary care practices in Devon.Methods
Six hundred and thirty two patients on COPD registers in primary care practices were seen by a visiting Respiratory Specialist Nurse. Diagnoses were made according to the NICE guidelines. Reversibility testing was carried out either routinely or based on clinical indication in two sub-samples. Dyspnoea was assessed. Data were entered into a novel IT-based software which computed guideline-based treatment recommendations. Current and recommended treatments were compared.Results
Five hundred and eighty patients had spirometry. Diagnoses of COPD were confirmed in 422 patients (73%). Thirty nine patients were identified as asthma only, 94 had normal spirometry, 23 were restrictive and 2 had a cardiac disorder. Reversibility testing changed diagnosis of 11% of patients with airflow obstruction, and severity grading in 18%. Three quarters of patients with COPD had been offered practical help with smoking cessation. Short and long-acting anticholinergics and long acting beta-2 agonists had been under-prescribed; in 15–18% of patients they were indicated but not received. Inhaled steroids had been over-prescribed (recommended in 17%; taken by 60%), whereas only 4% of patients with a chronic productive cough were receiving mucolytics. Pulmonary rehabilitation was not available in some areas and was under-used in other areas.Conclusion
Diagnostic registers of COPD in primary care contain mistakes leading to inaccurate prevalence estimates and inappropriate treatment decisions. Use of pre-bronchodilator readings for diagnosis overestimates the prevalence and severity in a significant minority, thus post bronchodilator readings should be used. Management of stable COPD does often not correspond to guidelines. The IT system used in this study has the potential to improve diagnosis and management of COPD in primary care. 相似文献999.
Legal restrictions, high costs and environmental problems regarding the disposal of marine processing wastes have led to amplified interest in biotechnology research concerning the identification and extraction of additional high grade, low-volume by-products produced from shellfish waste treatments. Shellfish waste consisting of crustacean exoskeletons is currently the main source of biomass for chitin production. Chitin is a polysaccharide composed of N-acetyl-D-glucosamine units and the multidimensional utilization of chitin derivatives including chitosan, a deacetylated derivative of chitin, is due to a number of characteristics including: their polyelectrolyte and cationic nature, the presence of reactive groups, high adsorption capacities, bacteriostatic and fungistatic influences, making them very versatile biomolecules. Part A of this review aims to consolidate useful information concerning the methods used to extract and characterize chitin, chitosan and glucosamine obtained through industrial, microbial and enzymatic hydrolysis of shellfish waste. 相似文献
1000.