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1.
Glob Chang Biol ; 29(1): 5-6, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36196663

RESUMO

Antarctic marine species live in one of the most thermally stable environments on Earth. They have evolved in these cold stable conditions for many millions of years. The long period for evolution, the isolation and mixing of populations produced by glacial cycles and the environmental heterogeneity in terms of light, productivity and physical disturbance, has produced a diverse fauna with an estimated 20 000 species, or more, living on the seabed. It has also produced a fauna that is possibly the most sensitive to warming on Earth in an environment that is changing faster than most, if not all, others. There is a great need to understand this threatened biodiversity and to find ways to mitigate the future prospects of species loss in this special environment that supports unique biology including the only vertebrate species on Earth that live without haemoglobin.


Assuntos
Anfípodes , Biodiversidade , Animais , Oceanos e Mares , Regiões Antárticas , Ecossistema
2.
Dig Dis Sci ; 61(10): 2812-2822, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27307064

RESUMO

BACKGROUND: Barrett's esophagus (BE) is a condition that has a small but important risk of progressing to esophageal cancer. To date, no study has assessed the strength of evidence supporting the recommendations for BE. We sought to assess the overall quality of the recommendations and strength of the BE using the AGREE II instrument. METHODS: A PubMed search was performed to identify guidelines published pertaining to BE. Every guideline was reviewed using the AGREE II format to assess the methodological rigor and validity of the guideline. Additionally, guidelines were reviewed for the level of evidence used to support recommendations, conflicts of interest (COI), and differences in recommendations. Statistical analysis was performed using Stata (version 12). RESULTS: In total, 234 manuscripts were identified of which 8 guidelines published between 2005 and 2013 pertained to BE. Seventy-five percentage (6/8) graded the evidence used to formulate recommendations. Of the 126 recommendations with supporting evidence, 6 % were supported by level A evidence, 49 % level B evidence, and 45 % level C evidence. Using the AGREE II format, the highest overall assessment grade was the BSG BE guideline (6.5 ± 0.6) followed by the AGA (5.5 ± 0.6). The highest rated domains were scope and purpose (mean 77 range 24-96) and clarity of presentation (mean 75), while the lowest rated domains were editorial independence (mean 32 range 0-92) and applicability of the guideline (mean 35 range 7-90). There was significant variability in recommendations regarding who to screen for BE and surveillance intervals. Finally, only 50 % of the guidelines disclosed if COI were present and 75 % (3/4) reported potentially relevant COI. CONCLUSIONS: Majority of the BE guideline fail to meet the AGREE II domains, and most of the recommendations are level B or C quality evidence. Further interventions are necessary to improve the overall quality of the guidelines.


Assuntos
Esôfago de Barrett/terapia , Conflito de Interesses , Medicina Baseada em Evidências , Guias de Prática Clínica como Assunto/normas , Esôfago de Barrett/diagnóstico , Gerenciamento Clínico , Humanos
3.
Semin Arthritis Rheum ; 45(4): 379-85, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26522136

RESUMO

OBJECTIVE: To determine the validity of the hip and knee osteoarthritis guidelines. METHODS: A systematic search of PubMed using a combination of Mesh and text terms with limitations to guidelines was performed to identify hip and knee osteoarthritis guidelines. The study was performed from April 17, 2014 to October 1, 2014. Guidelines were reviewed for graded levels of evidence, methods used to grade the evidence, and disclosures of conflicts of interest. Additionally, guidelines were also assessed for key quality measures using the AGREE II system for assessing the quality of guidelines. RESULTS: A total of 13 guidelines relevant to the diagnosis and/or treatment of hip/knee osteoarthritis was identified. The 180 recommendations reviewed were supported by 231 pieces of evidence. In total, 35% (n = 80; range: 0-26) were supported by level A evidence, 15% (n = 35; range: 0-10) were by level B, and 50% (n = 116; range: 0-62) were by level C. Median age of the guidelines was 4 years (±4.8; range: 0-16) with no comments on planned updates. In total, 31% of the guidelines included patients in the development process. Only one guideline incorporated cost consideration, and only 15% of the guidelines addressed the surgical management of osteoarthritis. Additionally, 46% of guidelines did not comment on conflicts of interest (COI). When present, there was an average 29.8 COI. Notably, 82% of the COI were monetary support/consulting. CONCLUSIONS: In total, 50% of the hip/knee osteoarthritis guideline recommendations are based on lower quality evidence. Nearly half the guidelines fail to disclose relevant COI and when disclosed, multiple potential COI are present. Future hip/knee osteoarthritis guideline development committees should strive to improve the transparency and quality of evidence used to formulate practice guidelines.


Assuntos
Conflito de Interesses , Medicina Baseada em Evidências/normas , Osteoartrite do Quadril/terapia , Osteoartrite do Joelho/terapia , Guias de Prática Clínica como Assunto/normas , Revelação , Humanos , Sociedades Médicas
4.
J Neurophysiol ; 114(3): 1819-26, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26245316

RESUMO

Past neuroimaging studies have documented discrete regions of human temporal cortex that are more strongly activated by conspecific voice sounds than by nonvoice sounds. However, the mechanisms underlying this voice sensitivity remain unclear. In the present functional MRI study, we took a novel approach to examining voice sensitivity, in which we applied a signal detection paradigm to the assessment of multivariate pattern classification among several living and nonliving categories of auditory stimuli. Within this framework, voice sensitivity can be interpreted as a distinct neural representation of brain activity that correctly distinguishes human vocalizations from other auditory object categories. Across a series of auditory categorization tests, we found that bilateral superior and middle temporal cortex consistently exhibited robust sensitivity to human vocal sounds. Although the strongest categorization was in distinguishing human voice from other categories, subsets of these regions were also able to distinguish reliably between nonhuman categories, suggesting a general role in auditory object categorization. Our findings complement the current evidence of cortical sensitivity to human vocal sounds by revealing that the greatest sensitivity during categorization tasks is devoted to distinguishing voice from nonvoice categories within human temporal cortex.


Assuntos
Percepção Auditiva , Lobo Temporal/fisiologia , Voz , Adulto , Mapeamento Encefálico , Feminino , Humanos , Masculino
5.
PLoS One ; 7(4): e34655, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22509340

RESUMO

Defining ecologically relevant upper temperature limits of species is important in the context of environmental change. The approach used in the present paper estimates the relationship between rates of temperature change and upper temperature limits for survival in order to evaluate the maximum long-term survival temperature (Ts). This new approach integrates both the exposure time and the exposure temperature in the evaluation of temperature limits. Using data previously published for different temperate and Antarctic marine environments, we calculated Ts in each environment, which allowed us to calculate a new index: the Warming Allowance (WA). This index is defined as the maximum environmental temperature increase which an ectotherm in a given environment can tolerate, possibly with a decrease in performance but without endangering survival over seasonal or lifetime time-scales. It is calculated as the difference between maximum long-term survival temperature (Ts) and mean maximum habitat temperature. It provides a measure of how close a species, assemblage or fauna are living to their temperature limits for long-term survival and hence their vulnerability to environmental warming. In contrast to data for terrestrial environments showing that warming tolerance increases with latitude, results here for marine environments show a less clear pattern as the smallest WA value was for the Peru upwelling system. The method applied here, relating upper temperature limits to rate of experimental warming, has potential for wide application in the identification of faunas with little capacity to survive environmental warming.


Assuntos
Adaptação Fisiológica/fisiologia , Organismos Aquáticos/fisiologia , Meio Ambiente , Temperatura , Análise de Variância , Animais , Temperatura Baixa , Ecossistema , Geografia , Modelos Lineares , Análise de Sobrevida , Fatores de Tempo
6.
Oecologia ; 154(3): 479-84, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17899201

RESUMO

Animal responses to changing environments are most commonly studied in relation to temperature change. The current paradigm for marine ectotherms is that temperature limits are set through oxygen limitation. Oxygen limitation leads to progressive reductions in capacity to perform work or activity, and these are more important and proximate measures of a population's ability to survive. Here we measured the ability of a large Antarctic clam to rebury when removed from sediment at temperatures between -1.5 and 7.5 degrees C and at three oxygen concentrations, 10.2, 20.5 and 27.7%. The proportion of the population capable of reburying declined rapidly and linearly with temperature from around 65% at 0 degrees C to 0% at 6 degrees C in normoxia (20.5% O2). Decreasing oxygen to 10.2% reduced temperature limits for successful burial by around 2 degrees C, and increasing oxygen to 27.7% raised the limits by 1-1.5 degrees C. There was an interactive effect of body size and temperature on burying: the temperature limits of larger individuals were lower than smaller animals. Similarly, these size limits were increased by increasing oxygen availability. Considering data for all temperatures and oxygen levels, the fastest burying rates occurred at 3 degrees C, which is 2 degrees C above the maximum summer temperature at this site.


Assuntos
Bivalves/fisiologia , Tamanho Corporal , Oxigênio/metabolismo , Temperatura , Animais , Regiões Antárticas , Fatores de Tempo
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