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Overviews synthesising the results of multiple systematic reviews help inform evidence-based clinical practice. In this first of two companion papers, we evaluate the bibliometrics of overviews, including their prevalence and factors affecting citation rates and journal impact factor (JIF). We searched MEDLINE, Epistemonikos and Cochrane Database of Systematic Reviews (CDSR). We included overviews that: (a) synthesised reviews, (b) conducted a systematic search, (c) had a methods section and (d) examined a healthcare intervention. Multivariable regression was conducted to determine the association between citation density, JIF and six predictor variables. We found 1218 overviews published from 2000 to 2020; the majority (73%) were published in the most recent 5-year period. We extracted a selection of these overviews (n = 541; 44%) dated from 2000 to 2018. The 541 overviews were published in 307 journals; CDSR (8%), PLOS ONE (3%) and Sao Paulo Medical Journal (2%) were the most prevalent. The majority (70%) were published in journals with impact factors between 0.05 and 3.97. We found a mean citation count of 10 overviews per year, published in journals with a mean JIF of 4.4. In multivariable analysis, overviews with a high number of citations and JIFs had more authors, larger sample sizes, were open access and reported the funding source. An eightfold increase in the number of overviews was found between 2009 and 2020. We identified 332 overviews published in 2020, which is equivalent to one overview published per day. Overviews perform above average for the journals in which they publish.

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BACKGROUND: This is the first update of this review first published in 2009. When treating elevated blood pressure, doctors usually try to achieve a blood pressure target. That target is the blood pressure value below which the optimal clinical benefit is supposedly obtained. "The lower the better" approach that guided the treatment of elevated blood pressure for many years was challenged during the last decade due to lack of evidence from randomised trials supporting that strategy. For that reason, the standard blood pressure target in clinical practice during the last years has been less than 140/90 mm Hg for the general population of patients with elevated blood pressure. However, new trials published in recent years have reintroduced the idea of trying to achieve lower blood pressure targets. Therefore, it is important to know whether the benefits outweigh harms when attempting to achieve targets lower than the standard target. OBJECTIVES: The primary objective was to determine if lower blood pressure targets (any target less than or equal to 135/85 mm Hg) are associated with reduction in mortality and morbidity as compared with standard blood pressure targets (less than or equal to 140/ 90 mm Hg) for the treatment of patients with chronic arterial hypertension. The secondary objectives were: to determine if there is a change in mean achieved systolic blood pressure (SBP) and diastolic blood pressure (DBP associated with "lower targets" as compared with "standard targets" in patients with chronic arterial hypertension; and to determine if there is a change in withdrawals due to adverse events with "lower targets" as compared with "standard targets", in patients with elevated blood pressure. SEARCH METHODS: The Cochrane Hypertension Information Specialist searched the following databases for randomised controlled trials up to May 2019: the Cochrane Hypertension Specialised Register, CENTRAL (2019, Issue 4), Ovid MEDLINE, Ovid Embase, the WHO International Clinical Trials Registry Platform, and ClinicalTrials.gov. We also contacted authors of relevant papers regarding further published and unpublished work. The searches had no language restrictions. SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing patients allocated to lower or to standard blood pressure targets (see above). DATA COLLECTION AND ANALYSIS: Two review authors (JAA, VL) independently assessed the included trials and extracted data. Primary outcomes were total mortality; total serious adverse events; myocardial infarction, stroke, congestive heart failure, end stage renal disease, and other serious adverse events. Secondary outcomes were achieved mean SBP and DBP, withdrawals due to adverse effects, and mean number of antihypertensive drugs used. We assessed the risk of bias of each trial using the Cochrane risk of bias tool and the certainty of the evidence using the GRADE approach.  MAIN RESULTS: This update includes 11 RCTs involving 38,688 participants with a mean follow-up of 3.7 years. This represents 7 new RCTs compared with the original version. At baseline the mean weighted age was 63.1 years and the mean weighted blood pressure was 155/91 mm Hg. Lower targets do not reduce total mortality (risk ratio (RR) 0.95, 95% confidence interval (CI) 0.86 to 1.05; 11 trials, 38,688 participants; high-certainty evidence) and do not reduce total serious adverse events (RR 1.04, 95% CI 0.99 to 1.08; 6 trials, 18,165 participants; moderate-certainty evidence). This means that the benefits of lower targets do not outweigh the harms as compared to standard blood pressure targets. Lower targets may reduce myocardial infarction (RR 0.84, 95% CI 0.73 to 0.96; 6 trials, 18,938 participants, absolute risk reduction (ARR) 0.4%, number needed to treat to benefit (NNTB) 250 over 3.7 years) and congestive heart failure (RR 0.75, 95% CI 0.60 to 0.92; 5 trials, 15,859 participants, ARR 0.6%, NNTB  167 over 3.7 years) (low-certainty for both outcomes). Reduction in myocardial infarction and congestive heart failure was not reflected in total serious adverse events. This may be due to an increase in other serious adverse events (RR 1.44, 95% CI 1.32 to 1.59; 6 trials. 18,938 participants, absolute risk increase (ARI) 3%,  number needed to treat to harm (NNTH) 33 over four years) (low-certainty evidence). Participants assigned to a "lower" target received one additional antihypertensive medication and achieved a significantly lower mean SBP (122.8 mm Hg versus 135.0 mm Hg, and a lower mean DBP (82.0 mm Hg versus 85.2 mm Hg, than those assigned to "standard target". AUTHORS' CONCLUSIONS: For the general population of persons with elevated blood pressure, the benefits of trying to achieve a lower blood pressure target rather than a standard target (≤ 140/90 mm Hg) do not outweigh the harms associated with that intervention. Further research is needed to see if some groups of patients would benefit or be harmed by lower targets. The results of this review are primarily applicable to older people with moderate to high cardiovascular risk. They may not be applicable to other populations.

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Climate change is predicted to impact tropical mangrove forests due to decreased rainfall, sea-level rise, and increased seasonality of flooding. Such changes are likely to influence habitat quality for migratory songbirds occupying mangrove wetlands during the tropical dry season. Overwintering habitat quality is known to be associated with fitness in migratory songbirds, yet studies have focused primarily on territorial species. Little is known about the ecology of nonterritorial species that may display more complex movement patterns within and among habitats of differing quality. In this study, we assess within-season survival and movement at two spatio-temporal scales of a nonterritorial overwintering bird, the prothonotary warbler (Protonotaria citrea), that depends on mangroves and tropical lowland forests. Specifically, we (a) estimated within-patch survival and persistence over a six-week period using radio-tagged birds in central Panama and (b) modeled abundance and occupancy dynamics at survey points throughout eastern Panama and northern Colombia as the dry season progressed. We found that site persistence was highest in mangroves; however, the probability of survival did not differ among habitats. The probability of warbler occupancy increased with canopy cover, and wet habitats were least likely to experience local extinction as the dry season progressed. We also found that warbler abundance is highest in forests with the tallest canopies. This study is one of the first to demonstrate habitat-dependent occupancy and movement in a nonterritorial overwintering migrant songbird, and our findings highlight the need to conserve intact, mature mangrove, and lowland forests.

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BACKGROUND: When treating elevated blood pressure (BP), doctors often want to know what blood pressure target they should try to achieve. The standard blood pressure target in clinical practice for some time has been less than 140 - 160/90 - 100 mmHg for the general population of people with elevated blood pressure. Several clinical guidelines published in recent years have recommended lower targets (less than 130/80 mmHg) for people with diabetes mellitus. It is not known whether attempting to achieve targets lower than the standard target reduces mortality and morbidity in those with elevated blood pressure and diabetes. OBJECTIVES: To determine if 'lower' BP targets (any target less than 130/85 mmHg) are associated with reduction in mortality and morbidity compared with 'standard' BP targets (less than 140 - 160/90 - 100 mmHg) in people with diabetes. SEARCH METHODS: We searched the Database of Abstracts of Reviews of Effectiveness (DARE) and the Cochrane Database of Systematic Reviews for related reviews. We conducted electronic searches of the Hypertension Group Specialised Register (January 1946 - October 2013), the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 9), MEDLINE (January 1946 - October 2013), EMBASE (January 1974 - October 2013) and ClinicalTrials.gov. The most recent search was performed on October 4, 2013.Other search sources were the International Clinical Trials Registry Platform (WHO ICTRP), and reference lists of all papers and relevant reviews. SELECTION CRITERIA: Randomized controlled trials comparing people with diabetes randomized to lower or to standard BP targets as previously defined, and providing data on any of the primary outcomes below. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed and established the included trials and data entry. Primary outcomes were total mortality; total serious adverse events; myocardial infarction, stroke, congestive heart failure and end-stage renal disease. Secondary outcomes were achieved mean systolic and diastolic BP, and withdrawals due to adverse effects. MAIN RESULTS: We found five randomized trials, recruiting a total of 7314 participants and with a mean follow-up of 4.5 years. Only one trial (ACCORD) compared outcomes associated with 'lower' (< 120 mmHg) or 'standard' (< 140 mmHg) systolic blood pressure targets in 4734 participants. Despite achieving a significantly lower BP (119.3/64.4 mmHg vs 133.5/70.5 mmHg, P < 0.0001), and using more antihypertensive medications, the only significant benefit in the group assigned to 'lower' systolic blood pressure (SBP) was a reduction in the incidence of stroke: risk ratio (RR) 0.58, 95% confidence interval (CI) 0.39 to 0.88, P = 0.009, absolute risk reduction 1.1%. The effect of SBP targets on mortality was compatible with both a reduction and increase in risk: RR 1.05 CI 0.84 to 1.30, low quality evidence. Trying to achieve the 'lower' SBP target was associated with a significant increase in the number of other serious adverse events: RR 2.58, 95% CI 1.70 to 3.91, P < 0.00001, absolute risk increase 2.0%.Four trials (ABCD-H, ABCD-N, ABCD-2V, and a subgroup of HOT) specifically compared clinical outcomes associated with 'lower' versus 'standard' targets for diastolic blood pressure (DBP) in people with diabetes. The total number of participants included in the DBP target analysis was 2580. Participants assigned to 'lower' DBP had a significantly lower achieved BP: 128/76 mmHg vs 135/83 mmHg, P < 0.0001. There was a trend towards reduction in total mortality in the group assigned to the 'lower' DBP target (RR 0.73, 95% CI 0.53 to 1.01), mainly due to a trend to lower non-cardiovascular mortality. There was no difference in stroke (RR 0.67, 95% CI 0.42 to 1.05), in myocardial infarction (RR 0.95, 95% CI 0.64 to 1.40) or in congestive heart failure (RR 1.06, 95% CI 0.58 to 1.92), low quality evidence. End-stage renal failure and total serious adverse events were not reported in any of the trials. A sensitivity analysis of trials comparing DBP targets < 80 mmHg (as suggested in clinical guidelines) versus < 90 mmHg showed similar results. There was a high risk of selection bias for every outcome analyzed in favor of the 'lower' target in the trials included for the analysis of DBP targets. AUTHORS' CONCLUSIONS: At the present time, evidence from randomized trials does not support blood pressure targets lower than the standard targets in people with elevated blood pressure and diabetes. More randomized controlled trials are needed, with future trials reporting total mortality, total serious adverse events as well as cardiovascular and renal events.

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While water and sanitation are now recognized as a human right by the United Nations, monitoring inequality in safe water access poses challenges. This study uses survey data to calculate household socio-economic-status (SES) indices in seven countries where national drinking-water quality surveys are available. These are used to assess inequalities in access as indicated by type of improved water source, use of safe water, and a combination of these. In Bangladesh, arsenic exposure through drinking-water is not significantly related to SES (p = 0.06) among households using tubewells, whereas in Peru, chlorine residual in piped systems varies significantly with SES (p < 0.0001). In Ethiopia, Nicaragua, and Nigeria, many poor households access nonpiped improved sources, which may provide unsafe water, resulting in greater inequality of access to "safe" water compared to "improved" water sources. Concentration indices increased from 0.08 to 0.15, 0.10 to 0.14, and 0.24 to 0.26, respectively, in these countries. There was minimal difference in Jordan and Tajikistan. Although the results are likely to be underestimates as they exclude individual-level inequalities, they show that use of a binary "improved"/"unimproved" categorization masks substantial inequalities. Future international monitoring programmes should take account of inequality in access and safety.

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BACKGROUND: People with no previous cardiovascular events or cardiovascular disease represent a primary prevention population. The benefits and harms of treating mild hypertension in primary prevention patients are not known at present. This review examines the existing randomized controlled trial (RCT) evidence. OBJECTIVE: Primary objective: To quantify the effects of antihypertensive drug therapy on mortality and morbidity in adults with mild hypertension (systolic blood pressure (BP) 140-159 mmHg and/or diastolic BP 90-99 mmHg) and without cardiovascular disease. METHODS: Search: We searched CENTRAL (2011, Issue 1), MEDLINE (1948 to May 2011), EMBASE (1980 to May 2011) and reference lists of articles. The Cochrane Database of Systematic Reviews and the Database of Abstracts of Reviews of Effectiveness (DARE) were searched for previous reviews and meta-analyses of anti-hypertensive drug treatment compared to placebo or no treatment trials up until the end of 2011. Selection criteria: RCTs of at least 1 year duration. Data collection and analysis: The outcomes assessed were mortality, stroke, coronary heart disease (CHD), total cardiovascular events (CVS), and withdrawals due to adverse effects. MAIN RESULTS: Of 11 RCTs identified 4 were included in this review, with 8,912 participants. Treatment for 4 to 5 years with antihypertensive drugs as compared to placebo did not reduce total mortality (RR 0.85, 95% CI 0.63, 1.15). In 7,080 participants treatment with antihypertensive drugs as compared to placebo did not reduce coronary heart disease (RR 1.12, 95% CI 0.80, 1.57), stroke (RR 0.51, 95% CI 0.24, 1.08), or total cardiovascular events (RR 0.97, 95% CI 0.72, 1.32). Withdrawals due to adverse effects were increased by drug therapy (RR 4.80, 95% CI 4.14, 5.57), ARR 9%. AUTHORS' CONCLUSIONS: Antihypertensive drugs used in the treatment of adults (primary prevention) with mild hypertension (systolic BP 140-159 mmHg and/or diastolic BP 90-99 mmHg) have not been shown to reduce mortality or morbidity in RCTs. Treatment caused 9% of patients to discontinue treatment due to adverse effects. More RCTs are needed in this prevalent population to know whether the benefits of treatment exceed the harms.

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BACKGROUND: When treating elevated blood pressure, doctors need to know what blood pressure (BP) target they should try to achieve. The standard of clinical practice for some time has been

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Este trabalho apresenta os objetivos, a metodologia e os resultados iniciais de um esforço de pensar cenários para o Brasil em 2022, e demonstra a importância e a viabilidade do uso de cenários para planejar os rumos do país. São apresentados os cenários globais e institucionais elaborados por uma equipe do IEA no Projeto "Brasil 3 Tempos", coordenado pelo Núcleo de Assuntos Estratégicos da Presidência da República. Os resultados demonstram que é possível integrar de maneira produtiva as opiniões de um grupo de mais de duzentos especialistas, criando de maneira estruturada um conjunto de cenários consistentes e plausíveis sobre o futuro. Visões estruturadas do futuro são fundamentais para definirmos as ações estratégicas de longo prazo indispensáveis para alcançarmos um cenário futuro desejado, diante das múltiplas oportunidades e desafios de um mundo em transformação.

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Squirrel monkeys are the most commonly used New World primates in biomedical research, but in vitro studies are restricted by the limited number of cell lines available from this species. We report here the development and characterization of a continuous, kidney epithelial cell line (SQMK-FP cells) derived from a newborn squirrel monkey. Karyotype was consistent with Bolivian squirrel monkey (submetacentric chromosome pair 15 and acrocentric chromosome pair 16). All cells examined were hyperdiploid with chromosome numbers ranging from 52 to 57. Ultrastructural analysis of SQMK-FP cells revealed the presence of cell junctions with radiating filaments, indicating desmosomes and numerous surface projections containing longitudinally oriented filaments typical of tubular epithelium. Biochemically, SQMK-FP cells exhibit glucocorticoid resistance typical of the squirrel monkey. Glucocorticoid receptor (GR) binding is low in SQMK-FP cells because of high expression of the FK506-binding immunophilin FKBP51 that inhibits GR binding. SQMK-FP cells constitute a tubular epithelial cell line that has biochemical properties characteristic of squirrel monkeys and represents an alternate cell model to B-lymphoblast SML cells to study the biology of the squirrel monkey in vitro.

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Realiza o exame das propostas em discussão para tentar extrair os elementos plausíveis em cada alternativa apresentada e compô-las num todo consistente. Tais propostas são examinadas a partir de amplo pano de fundo teórico e histórico que ajuda a identificar virtudes e vícios das alternativas hoje em pauta. Convém prevenir que o resultado final não é a exposição de um "modelo" acabado para o regime de concessões para a exploração de serviços de utilidade pública, pois este, se existir, deverá ser fruto de difícil e prolongado processo de reflexão, experiências e negociações.

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Elabora um trabalho de estruturaçäo de objetivos de definiçäo e de diretrizes para um hospital universitário

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