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1.
J Stroke Cerebrovasc Dis ; 33(5): 107637, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38360251

RESUMO

BACKGROUND: The pattern of surgical treatments for Idiopathic Intracranial Hypertension (IIH) in the United States is not well-studied, specifically the trend of utilizing endovascular venous stenting (EVS) as an emerging technique. METHODS: In this cross-sectional study, we aimed to explore the national trend of utilizing different procedures for the treatment of IIH including EVS, Optic Nerve Sheath Fenestration (ONSF), and CSF Shunting, with a focus on novel endovascular procedures. Moreover, we explored rates of 90-day readmission and length of hospital stay following different procedures, besides the effects of sociodemographic and clinical parameters on procedure choice. RESULTS: 36,437 IIH patients were identified from records between 2010 and 2018. Those in the EVS group were 29 years old on average, and 93.4 % were female. Large academic hospital setting was independently associated with higher EVS utilization, while other factors were not predictive of procedure choice. The proportion of EVS use in IIH hospitalizations increased significantly from 2010 to 2018 (P < 0.001), while there was a relative decline in the frequency of shunting procedures (P = 0.001), with ONSF utilization remaining stable (P = 0.39). The rate of 90-day readmission and length of hospital stay were considerably lower following EVS compared to other procedures (Ps < 0.001). CONCLUSION: This study presents novel population-level data on national trends in the frequency and outcome of EVS for IIH therapy. EVS was associated with shorter length of hospital stays and fewer readmission rates. In addition, a continuous increase in venous stenting compared to other procedures suggests an increasing role for endovascular therapies in IIH.


Assuntos
Procedimentos Endovasculares , Hipertensão Intracraniana , Pseudotumor Cerebral , Humanos , Feminino , Adulto , Masculino , Pseudotumor Cerebral/cirurgia , Estudos Transversais , Procedimentos Neurocirúrgicos/efeitos adversos , Procedimentos Neurocirúrgicos/métodos , Procedimentos Endovasculares/efeitos adversos , Stents
2.
J Hosp Infect ; 132: 62-72, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36473552

RESUMO

BACKGROUND: Solid organ and haematopoietic stem cell transplant recipients are more vulnerable to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) than non-transplant recipients due to immunosuppression, and may pose a continued transmission risk, especially within hospital settings. Detailed case reports including symptoms, viral load and infectiousness, defined by the presence of replication-competent viruses in culture, provide an opportunity to examine the relationship between clinical course, burden and contagiousness, and provide guidance on release from isolation. OBJECTIVES: To investigate the relationship between serial SARS-CoV-2 reverse transcription polymerase chain reaction (RT-PCR) cycle threshold (Ct) value or cycle of quantification value, or other measures of viral burden and the likelihood and duration of the presence of infectious virus based on viral culture, including the influence of age, sex, underlying pathologies, degree of immunosuppression, and/or vaccination on this relationship, in transplant recipients. METHODS: LitCovid, medRxiv, Google Scholar and the World Health Organization COVID-19 database were searched from 1st November 2019 to 26th October 2022. Studies reporting relevant data (results from serial RT-PCR testing and viral culture data from the same respiratory samples) for transplant recipients with SARS-CoV-2 infection were included in this systematic review: Methodological quality was assessed using five criteria, and the data were synthesized narratively and graphically. RESULTS: Thirteen case reports and case series reporting on 41 transplant recipients (22 renal, five cardiac, one bone marrow, two liver, one bilateral lung and 10 blood stem cell) were included in this review. A relationship was observed between proxies of viral burden and likelihood of shedding replication-competent SARS-CoV-2. Three individuals shed replication-competent viruses for >100 days after symptom onset. Lack of standardization of testing and reporting platforms precludes establishing a definitive viral burden cut-off. However, the majority of transplant recipients stopped shedding replication-competent viruses when the Ct value was >30 despite differences across platforms. CONCLUSIONS: Viral burden is a reasonable proxy for infectivity when considered within the context of the clinical status of each patient. Standardized study design and reporting are essential to standardize guidance based on an increasing evidence base.


Assuntos
COVID-19 , Transplante de Órgãos , Humanos , COVID-19/diagnóstico , SARS-CoV-2 , Carga Viral , Células-Tronco Hematopoéticas
3.
JAMA Netw Open ; 5(11): e2244221, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36445703

RESUMO

Importance: Firearm fatality rates in the United States have reached a 28-year high. Describing the evolution of firearm fatality rates across intents, demographics, and geography over time may highlight high-risk groups and inform interventions for firearm injury prevention. Objective: To understand variations in rates of firearm fatalities stratified by intent, demographics, and geography in the US. Design, Setting, and Participants: This cross-sectional study analyzed firearm fatalities in the US from 1990 to 2021 using data from the Centers for Disease Control and Prevention. Heat maps, maximum and mean fatality rate graphs, and choropleth maps of county-level rates were created to examine trends in firearm fatality rates by intent over time by age, sex, race, ethnicity, and urbanicity of individuals who died from firearms. Data were analyzed from December 2018 through September 2022. Main Outcomes and Measures: Rates of firearm fatalities by age, sex, race, ethnicity, urbanicity, and county of individuals killed stratified by specific intent (suicide or homicide) per 100 000 persons per year. Results: There were a total of 1 110 421 firearm fatalities from 1990 to 2021 (952 984 among males [85.8%] and 157 165 among females [14.2%]; 286 075 among Black non-Hispanic individuals [25.8%], 115 616 among Hispanic individuals [10.4%], and 672 132 among White non-Hispanic individuals [60.5%]). All-intents total firearm fatality rates per 100 000 persons declined to a low of 10.1 fatalities in 2004, then increased to 14.7 fatalities (45.5% increase) by 2021. From 2014 to 2021, male and female firearm homicide rates per 100 000 persons per year increased from 5.9 to 10.9 fatalities (84.7% increase) and 1.1 to 2.0 fatalities (87.0% increase), respectively. Firearm suicide rates were highest among White non-Hispanic men aged 80 to 84 years (up to 46.8 fatalities/100 000 persons in 2021). By 2021, maximum rates of firearm homicide were up to 22.5 times higher among Black non-Hispanic men (up to 141.8 fatalities/100 000 persons aged 20-24 years) and up to 3.6 times higher among Hispanic men (up to 22.8 fatalities/100 000 persons aged 20-24 years) compared with White non-Hispanic men (up to 6.3 fatalities/100 000 persons aged 30-34 years). Males had higher rates of suicide (14.1 fatalities vs 2.0 fatalities per 100 000 persons in 2021) and homicide (10.9 fatalities vs. 2.0 fatalities per 100 000 persons in 2021) compared with females. Metropolitan areas had higher homicide rates than nonmetropolitan areas (6.6 fatalities vs 4.8 fatalities per 100 000 persons in 2021). Firearm fatalities by county level increased over time, spreading from the West to the South. From 1999 to 2011 until 2014 to 2016, fatalities per 100 000 persons per year decreased from 10.6 to 10.5 fatalities in Western states and increased from 12.8 to 13.9 fatalities in Southern states. Conclusions and Relevance: This study found marked disparities in firearm fatality rates by demographic group, which increased over the past decade. These findings suggest that public health approaches to reduce firearm violence should consider underlying demographic and geographic trends and differences by intent.


Assuntos
Armas de Fogo , Suicídio , Ferimentos por Arma de Fogo , Estados Unidos/epidemiologia , Feminino , Masculino , Humanos , Estudos Transversais , Homicídio
4.
J Hosp Infect ; 130: 63-94, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36115620

RESUMO

BACKGROUND: The role of fomites in the transmission of SARS-CoV-2 is unclear. AIM: To assess whether SARS-CoV-2 can be transmitted through fomites, using evidence from viral culture studies. METHODS: Searches were conducted in the World Health Organization COVID-19 Database, PubMed, LitCovid, medRxiv, and Google Scholar to December 31st, 2021. Studies that investigated fomite transmission and performed viral culture to assess the cytopathic effect (CPE) of positive fomite samples and confirmation of SARS-CoV-2 as the cause of the CPE were included. The risk of bias using a checklist modified from the modified Quality Assessment of Diagnostic Accuracy Studies - 2 (QUADAS-2) criteria was assessed. FINDINGS: Twenty-three studies were included. The overall risk of bias was moderate. Five studies demonstrated replication-competent virus from fomite cultures and three used genome sequencing to match fomite samples with human clinical specimens. The mean cycle threshold (CT) of samples with positive viral culture was significantly lower compared with cultured samples that returned negative results (standardized mean difference: -1.45; 95% confidence interval (CI): -2.00 to -0.90; I2 = 0%; P < 0.00001). The likelihood of isolating replication-competent virus was significantly greater when CT was <30 (relative risk: 3.10; 95% CI: 1.32 to 7.31; I2 = 71%; P = 0.01). Infectious specimens were mostly detected within seven days of symptom onset. One study showed possible transmission of SARS-CoV-2 from fomites to humans. CONCLUSION: The evidence from published studies suggests that replication-competent SARS-CoV-2 is present on fomites. Replication-competent SARS-CoV-2 is significantly more likely when the PCR CT for clinical specimens and fomite samples is <30. Further studies should investigate the duration of infectiousness of SARS-CoV-2 and the frequency of transmission from fomites.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Fômites , COVID-19/diagnóstico
5.
Stroke ; 53(12): 3583-3593, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36148657

RESUMO

BACKGROUND: A 10-hospital regional network transitioned to tenecteplase as the standard of care stroke thrombolytic in September 2019 because of potential workflow advantages and reported noninferior clinical outcomes relative to alteplase in meta-analyses of randomized trials. We assessed whether tenecteplase use in routine clinical practice reduced thrombolytic workflow times with noninferior clinical outcomes. METHODS: We designed a prospective registry-based observational, sequential cohort comparison of tenecteplase- (n=234) to alteplase-treated (n=354) stroke patients. We hypothesized: (1) an increase in the proportion of patients meeting target times for target door-to-needle time and transfer door-in-door-out time, and (2) noninferior favorable (discharge to home with independent ambulation) and unfavorable (symptomatic intracranial hemorrhage, in-hospital mortality or discharge to hospice) in the tenecteplase group. Total hospital cost associated with each treatment was also compared. RESULTS: Target door-to-needle time within 45 minutes for all patients was superior for tenecteplase, 41% versus 29%; adjusted odds ratio, 1.85 (95% CI, 1.27-2.71); P=0.001; 58% versus 41% by Get With The Guidelines criteria. Target door-in-door-out time within 90 minutes was superior for tenecteplase 37% (15/43) versus 14% (9/65); adjusted odds ratio, 3.62 (95% CI, 1.30-10.74); P=0.02. Favorable outcome for tenecteplase fell within the 6.5% noninferiority margin; adjusted odds ratio, 1.26 (95% CI, 0.89-1.80). Unfavorable outcome was less for tenecteplase, 7.3% versus 11.9%, adjusted odds ratio, 0.77 (95% CI, 0.42-1.37) but did not fall within the prespecified 1% noninferior boundary. Net benefit (%favorable-%unfavorable) was greater for the tenecteplase sample: 37% versus 27%. P=0.02. Median cost per hospital encounter was less for tenecteplase cases ($13 382 versus $15 841; P<0.001). CONCLUSIONS: Switching to tenecteplase in routine clinical practice in a 10-hospital network was associated with shorter door-to-needle time and door-in-door-out times, noninferior favorable clinical outcomes at discharge, and reduced hospital costs. Evaluation in larger, multicenter cohorts is recommended to determine if these observations generalize.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Humanos , Isquemia Encefálica/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Tenecteplase/uso terapêutico , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento
7.
JAMA Pediatr ; 176(4): 365-372, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35072694

RESUMO

IMPORTANCE: Mindfulness curricula can improve physician burnout, but implementation during residency presents challenges. OBJECTIVE: To examine whether a novel mindfulness curriculum implemented in the first 6 months of internship reduces burnout. DESIGN, SETTING, AND PARTICIPANTS: This pragmatic, multicenter, stratified cluster randomized clinical trial of a mindfulness curriculum randomized 340 pediatric interns to the intervention or control arm within program pairs generated based on program size and region. Fifteen US pediatric training programs participated from June 14, 2017, to February 28, 2019. INTERVENTIONS: The intervention included 7 hour-long sessions of a monthly mindfulness curriculum (Mindfulness Intervention for New Interns) and a monthly mindfulness refresher implemented during internship. The active control arm included monthly 1-hour social lunches. MAIN OUTCOMES AND MEASURES: The primary outcome was emotional exhaustion (EE) as measured by the Maslach Burnout Inventory 9-question EE subscale (range, 7-63; higher scores correspond to greater perceived burnout). Secondary outcomes were depersonalization, personal accomplishment, and burnout. The study assessed mindfulness with the Five Facet Mindfulness Questionnaire and empathy with the Interpersonal Reactivity Index subscales of perspective taking and empathetic concern. Surveys were implemented at baseline, month 6, and month 15. RESULTS: Of the 365 interns invited to participate, 340 (93.2%; 255 [75.0%] female; 51 [15.0%] 30 years or older) completed surveys at baseline; 273 (74.8%) also participated at month 6 and 195 (53.4%) at month 15. Participants included 194 (57.1%) in the Mindfulness Intervention for New Interns and 146 (42.9%) in the control arm. Analyses were adjusted for baseline outcome measures. Both arms' EE scores were higher at 6 and 15 months than at baseline, but EE did not significantly differ by arm in multivariable analyses (6 months: 35.4 vs 32.4; adjusted difference, 3.03; 95% CI, -0.14 to 6.21; 15 months: 33.8 vs 32.9; adjusted difference, 1.42; 95% CI, -2.42 to 5.27). None of the 6 secondary outcomes significantly differed by arm at month 6 or month 15. CONCLUSIONS AND RELEVANCE: A novel mindfulness curriculum did not significantly affect EE, burnout, empathy, or mindfulness immediately or 9 months after curriculum implementation. These findings diverge from prior nonrandomized studies of mindfulness interventions, emphasizing the importance of rigorous study design and suggesting that additional study is needed to develop evidence-based methods to reduce trainee burnout. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03148626.


Assuntos
Esgotamento Profissional , Internato e Residência , Atenção Plena , Esgotamento Profissional/prevenção & controle , Esgotamento Profissional/psicologia , Esgotamento Psicológico , Criança , Currículo , Feminino , Humanos , Atenção Plena/educação , Atenção Plena/métodos , Inquéritos e Questionários
8.
JAMA Pediatr ; 176(2): e214822, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34807238

RESUMO

Importance: Youth firearm-related deaths are a public health crisis in the US. The association between county-level poverty and the risk of firearm-related deaths among youth is unknown, however. Objective: To examine the association between county-level poverty concentration and firearm-related mortality rates in US youth. Design, Setting, and Participants: This cross-sectional study analyzed US firearm fatalities in children and young adults aged 5 to 24 years that occurred between January 1, 2007, and December 31, 2016. Data were obtained from the Centers for Disease Control and Prevention's Compressed Mortality File, and annual intercensal county population data were obtained from the US Census Bureau. Data analyses were conducted between November 1, 2019, and June 30, 2020. Exposures: County-level poverty was categorized into 5 groups: 0% to 4.9%, 5% to 9.9%, 10% to 14.9%, 15% to 19.9%, and ≥20% of the population living below the federal poverty level. Main Outcomes and Measures: The main outcomes were firearm-related deaths in total and by specific intent (homicide, suicide, and unintentional) per 100 000 youths over the entire study period. Multivariable negative binomial regression models were used to analyze the association between firearm-related mortality rates and county poverty concentration, controlling for demographic variables, urbanicity, and statewide firearm prevalence. Adjusted incidence rate ratios (IRRs) were calculated, and statewide firearm prevalence was estimated. The population-attributable fraction (PAF) and years of potential life lost for each intent were calculated. Results: A total of 67 905 firearm-related deaths among youth (predominantly composed of 60 164 male individuals [88.6%]) from 2007 to 2016 were analyzed. Of these deaths, 42 512 were homicides (62.6%), 23 034 were suicides (33.9%), and 1627 were unintentional (2.4%). Firearm-related mortality risk increased in a stepwise manner with increasing county poverty concentration. Compared with counties with the lowest poverty concentration, counties with the highest poverty concentration had an increased rate of total firearm-related deaths (adjusted IRR, 2.29; 95% CI, 1.96-2.67), homicides (adjusted IRR, 3.55; 95% CI, 2.80-4.51), suicides (adjusted IRR, 1.45; 95% CI, 1.20-1.75), and unintentional deaths (adjusted IRR, 9.32; 95% CI, 2.32-37.4). The PAF was 0.51 (95% CI, 0.43-0.57) for all firearm-related deaths, 0.66 (95% CI, 0.57-0.73) for homicides, 0.30 (95% CI, 0.17-0.42) for suicides, and 0.86 (95% CI, 0.46-0.97) for unintentional deaths. This calculation translated to 34 292 firearm-related deaths that would not have occurred if all counties had the same risk as counties with the lowest poverty concentration. A total of 3 833 105 years of potential life lost was observed. Conclusions and Relevance: This study found an association between firearm-related mortality rates among youth and county-level poverty concentration. With more than half of firearm-related deaths and two-thirds of firearm-related homicides potentially associated with living in an area with a high concentration of poverty, a multidimensional strategy to reduce poverty and firearm-related deaths is urgently needed.


Assuntos
Armas de Fogo , Homicídio , Pobreza , Suicídio , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Feminino , Homicídio/estatística & dados numéricos , Humanos , Masculino , Pobreza/estatística & dados numéricos , Estudos Retrospectivos , Suicídio/estatística & dados numéricos , Estados Unidos/epidemiologia , Adulto Jovem
9.
J Stroke Cerebrovasc Dis ; 30(6): 105569, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33862541

RESUMO

BACKGROUND AND PURPOSE: Delayed evaluation of stroke may contribute to COVID-19 pandemic-related morbidity and mortality. This study evaluated patient characteristics, process measures and outcomes associated with the decline in stroke presentation during the early pandemic. METHODS: Volumes of stroke presentations, intravenous thrombolytic administrations, and mechanical thrombectomies from 52 hospitals from January 1-June 30, 2020 were analyzed with piecewise linear regression and linear spline models. Univariate analysis compared pandemic (case) and pre-pandemic (control) groups defined in relation to the nadir of daily strokes during the study period. Significantly different patient characteristics were further evaluated with logistic regression, and significantly different process measures and outcomes were re-analyzed after propensity score matching. RESULTS: Analysis of 7,389 patients found daily stroke volumes decreased 0.91/day from March 12-26 (p < 0.0001), reaching a nadir 35.0% less than expected, and increased 0.15 strokes/day from March 27-June 23, 2020 (p < 0.0001). Intravenous thrombolytic administrations decreased 3.3/week from February 19-March 31 (p = 0.0023), reaching a nadir 33.4% less than expected, and increased 1.4 administrations/week from April 1-June 23 (p < 0.0001). Mechanical thrombectomy volumes decreased by 1.5/week from February 19-March 31, 2020 (p = 0.0039), reaching a nadir 11.3% less than expected. The pandemic group was more likely to ambulate independently at baseline (p = 0.02, OR = 1.60, 95% CI = 1.08-2.42), and less likely to present with mild stroke symptoms (NIH Stroke Scale ≤ 5; p = 0.04, OR = 1.01, 95% CI = 1.00-1.02). Process measures and outcomes of each group did not differ, including door-to-needle time, door-to-puncture time, and successful mechanical thrombectomy rate. CONCLUSION: Stroke presentations and acute interventions decreased during the early COVID-19 pandemic, at least in part due to patients with lower baseline functional status and milder symptoms not seeking medical care. Public health messaging and initiatives should target these populations.


Assuntos
COVID-19 , Diagnóstico Tardio/tendências , Avaliação de Processos e Resultados em Cuidados de Saúde/tendências , Aceitação pelo Paciente de Cuidados de Saúde , Acidente Vascular Cerebral/terapia , Trombectomia/tendências , Terapia Trombolítica/tendências , Tempo para o Tratamento/tendências , Idoso , Idoso de 80 Anos ou mais , Feminino , Estado Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Indicadores de Qualidade em Assistência à Saúde/tendências , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
10.
Biol Lett ; 17(1): 20200708, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33497589

RESUMO

Southern Ocean ecosystems are rapidly changing due to climate variability. An apparent beneficiary of such change in the western Antarctic Peninsula (WAP) is the gentoo penguin Pygoscelis papua, which has increased its population size and expanded its range southward in the last 20 years. To better understand how this species has responded to large-scale changes, we tracked individuals during the non-breeding winter period from five colonies across the latitudinal range of breeding sites in the WAP, including from a recently established colony. Results highlight latitudinal gradients in movement; strong associations with shallow, coastal habitats along the entire Antarctic Peninsula; and movements that are independent of, yet constrained by, sea ice. It is clear that coastal habitats essential to gentoo penguins during the breeding season are similarly critical during winter. Larger movements of birds from northern colonies in the WAP further suggest that leap-frog migration may influence colonization events by facilitating nest-area prospecting and use of new haul-out sites. Our results support efforts to develop a marine protected area around the WAP. Winter habitats used by gentoo penguins outline high priority areas for improving the management of the spatio-temporally concentrated krill (Euphausia superba) fishery that operates in this region during winter.


Assuntos
Euphausiacea , Spheniscidae , Animais , Regiões Antárticas , Ecossistema , Camada de Gelo
11.
Biol Lett ; 16(12): 20200645, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33321063

RESUMO

Estimating when and where survival bottlenecks occur in free-ranging marine predators is critical for effective demographic monitoring and spatial planning. This is particularly relevant to juvenile stages of long-lived species for which direct observations of death are typically not possible. We used satellite telemetry data from fledgling Adélie, chinstrap and gentoo penguins near the Antarctic Peninsula to estimate the spatio-temporal scale of a bottleneck after fledging. Fledglings were tracked up to 106 days over distances of up to 2140 km. Cumulative losses of tags increased to 73% within 16 days of deployment, followed by an order-of-magnitude reduction in loss rates thereafter. The timing and location of tag losses were consistent with at-sea observations of penguin carcasses and bioenergetics simulations of mass loss to thresholds associated with low recruitment probability. A bootstrapping procedure is used to assess tag loss owing to death versus other factors. Results suggest insensitivity in the timing of the bottleneck and quantify plausible ranges of mortality rates within the bottleneck. The weight of evidence indicates that a survival bottleneck for fledgling penguins is acute, attributable to predation and starvation, and may account for at least 33% of juvenile mortality.


Assuntos
Spheniscidae , Animais , Regiões Antárticas
12.
Chirality ; 32(9): 1186-1190, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32627234

RESUMO

In this paper, we investigate the physical basis behind the molecular biochirality from the computation of a parity violation energy difference (PVED) in enantiomers of organic molecules (e.g., amino acids, which occur as levogyrous-type in nature), by considering the influence of fundamental interactions beyond the standard model of elementary particles and interactions. Particularly, we study the role of a 4-D Chern-Simons theory at the origin of this PVED, the Carroll-Field-Jackiw electrodynamics, which violates both Lorentz and parity symmetries. Then, we consider terrestrial and Jovian scenarios where the influence of a modified (effective) magnetic field generated by the planets on the molecules is taken into account in the calculation of PVED. Besides this quantity, we also calculate the relative quantity excess of an enantiomer over the other in a thermal bath. Finally, we compare the obtained results with those ones from other models based on fundamental interactions.

13.
Nature ; 580(7801): 87-92, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32238927

RESUMO

Southern Ocean ecosystems are under pressure from resource exploitation and climate change1,2. Mitigation requires the identification and protection of Areas of Ecological Significance (AESs), which have so far not been determined at the ocean-basin scale. Here, using assemblage-level tracking of marine predators, we identify AESs for this globally important region and assess current threats and protection levels. Integration of more than 4,000 tracks from 17 bird and mammal species reveals AESs around sub-Antarctic islands in the Atlantic and Indian Oceans and over the Antarctic continental shelf. Fishing pressure is disproportionately concentrated inside AESs, and climate change over the next century is predicted to impose pressure on these areas, particularly around the Antarctic continent. At present, 7.1% of the ocean south of 40°S is under formal protection, including 29% of the total AESs. The establishment and regular revision of networks of protection that encompass AESs are needed to provide long-term mitigation of growing pressures on Southern Ocean ecosystems.


Assuntos
Sistemas de Identificação Animal , Organismos Aquáticos/fisiologia , Mudança Climática/estatística & dados numéricos , Conservação dos Recursos Naturais/métodos , Ecossistema , Oceanos e Mares , Comportamento Predatório , Animais , Regiões Antárticas , Biodiversidade , Aves , Peixes , Cadeia Alimentar , Camada de Gelo , Mamíferos , Dinâmica Populacional
14.
Sci Data ; 7(1): 94, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188863

RESUMO

The Retrospective Analysis of Antarctic Tracking Data (RAATD) is a Scientific Committee for Antarctic Research project led jointly by the Expert Groups on Birds and Marine Mammals and Antarctic Biodiversity Informatics, and endorsed by the Commission for the Conservation of Antarctic Marine Living Resources. RAATD consolidated tracking data for multiple species of Antarctic meso- and top-predators to identify Areas of Ecological Significance. These datasets and accompanying syntheses provide a greater understanding of fundamental ecosystem processes in the Southern Ocean, support modelling of predator distributions under future climate scenarios and create inputs that can be incorporated into decision making processes by management authorities. In this data paper, we present the compiled tracking data from research groups that have worked in the Antarctic since the 1990s. The data are publicly available through biodiversity.aq and the Ocean Biogeographic Information System. The archive includes tracking data from over 70 contributors across 12 national Antarctic programs, and includes data from 17 predator species, 4060 individual animals, and over 2.9 million observed locations.

15.
Sci Rep ; 10(1): 2314, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-32047241

RESUMO

Low catch limits for forage species are often considered to be precautionary measures that can help conserve marine predators. Difficulties measuring the impacts of fisheries removals on dependent predators maintain this perspective, but consideration of the spatio-temporal scales over which forage species, their predators, and fisheries interact can aid assessment of whether low catch limits are as precautionary as presumed. Antarctic krill are targeted by the largest fishery in the Southern Ocean and are key forage for numerous predators. Current krill removals are considered precautionary and have not been previously observed to affect krill-dependent predators, like penguins. Using a hierarchical model and 30+ years of monitoring data, we show that expected penguin performance was reduced when local harvest rates of krill were ≥0.1, and this effect was similar in magnitude to that of poor environmental conditions. With continued climate warming and high local harvest rates, future observations of penguin performance are predicted to be below the long-term mean with a probability of 0.77. Catch limits that are considered precautionary for forage species simply because the limit is a small proportion of the species' standing biomass may not be precautionary for their predators.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Comportamento Alimentar/fisiologia , Pesqueiros/normas , Comportamento Predatório/fisiologia , Spheniscidae/fisiologia , Animais , Regiões Antárticas , Biomassa , Monitoramento Ambiental , Densidade Demográfica
16.
PLoS One ; 14(12): e0226207, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31821380

RESUMO

A goal of tracking migratory animals is to characterize the habitats they use and to interpret population processes with respect to conditions experienced en route to, and within, overwintering areas. For migratory seabirds with broad breeding ranges, inferring population-level effects of environmental conditions that are experienced during migratory periods would benefit by directly comparing how birds from different breeding aggregations disperse, characterizing the physical conditions of areas they use, and determining whether they occupy shared foraging areas. We therefore tracked 41 adult and juvenile chinstrap penguins (Pygoscelis antarctica) from three breeding locations in the northern Antarctic Peninsula region during the austral winter of 2017. The satellite tracking data revealed overlap of individuals over continental shelf areas during autumn months (Mar-May), shared outbound corridors that track the southern Antarctic circumpolar current front, followed by occupancy of progressively colder, deeper, and ice-free waters that spanned the entire western hemisphere south of the Polar Front. Despite broadly similar physical environments used by individuals from different colonies, the proportion of birds from each colony that remained within 500km of their colony was positively correlated with their local population trends. This suggests that local migration strategies near the Antarctic Peninsula may benefit breeding populations. However, the magnitude of inter-colony and intra-colony overlap was generally low given the broad scale of habitats occupied. High individual variation in winter movements suggests that habitat selection among chinstrap penguins is more opportunistic, without clear colony-specific preference for fine-scale foraging hotspots. Mixing of individuals from multiple colonies across broad regions of the Southern Ocean would expose chinstrap penguins from the Antarctic Peninsula to a shared environmental experience that helps explain the regional decline in their abundance.


Assuntos
Migração Animal , Ecossistema , Spheniscidae/fisiologia , Animais , Regiões Antárticas , Oceanos e Mares , Estações do Ano
17.
Am J Cardiol ; 124(11): 1785-1789, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31590909

RESUMO

Aspirin use in the prevention of cardiovascular events has been a mainstay of treatment for decades. However, the use of aspirin in primary prevention of atherosclerotic cardiovascular disease has recently come under scrutiny. Several recent studies have evaluated the use of aspirin in primary prevention and the results suggest that in many patients the risks may outweigh the benefits. Closer examination of these trials suggests that the use of aspirin therapy for primary prevention may have a role but likely needs a more tailored approach and that caution is needed in prescribing aspirin for primary prevention. In conclusion, in this article we review the evolving evidence for aspirin in the primary prevention of atherosclerotic cardiovascular disease.


Assuntos
Aspirina/administração & dosagem , Doenças Cardiovasculares/prevenção & controle , Prevenção Primária/métodos , Aterosclerose/prevenção & controle , Relação Dose-Resposta a Droga , Humanos , Inibidores da Agregação Plaquetária/administração & dosagem
18.
Neurobiol Aging ; 74: 112-120, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30448611

RESUMO

The human electroencephalogram (EEG) of sleep undergoes profound changes with age. These changes can be conceptualized as "brain age (BA)," which can be compared to chronological age to reflect the degree of deviation from normal aging. Here, we develop an interpretable machine learning model to predict BA based on 2 large sleep EEG data sets: the Massachusetts General Hospital (MGH) sleep lab data set (N = 2532; ages 18-80); and the Sleep Heart Health Study (SHHS, N = 1974; ages 40-80). The model obtains a mean absolute deviation of 7.6 years between BA and chronological age (CA) in healthy participants in the MGH data set. As validation, a subset of SHHS containing longitudinal EEGs 5.2 years apart shows an average of 5.4 years increase in BA. Participants with significant neurological or psychiatric disease exhibit a mean excess BA, or "brain age index" (BAI = BA-CA) of 4 years relative to healthy controls. Participants with hypertension and diabetes have a mean excess BA of 3.5 years. The findings raise the prospect of using the sleep EEG as a potential biomarker for healthy brain aging.


Assuntos
Encéfalo/fisiologia , Eletroencefalografia/métodos , Envelhecimento Saudável/fisiologia , Sono/fisiologia , Adulto , Biomarcadores , Diabetes Mellitus/fisiopatologia , Feminino , Humanos , Hipertensão/fisiopatologia , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
19.
Ecol Evol ; 8(21): 10520-10529, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30464824

RESUMO

AIM: To provide a method of analyzing penguin tracking data to identify priority at-sea areas for seabird conservation (marine IBAs), based on pre-existing approaches for flying seabirds but revised according to the specific ecology of Pygoscelis penguin species. LOCATION: Waters around the Antarctic Peninsula, South Shetland, and South Orkney archipelagos (FAO Subareas 48.1 and 48.2). METHODS: We made key improvements to the pre-existing protocol for identifying marine IBAs that include refining the track interpolation method and revision of parameters for the kernel analysis (smoothing factor and utilization distribution) using sensitivity tests. We applied the revised method to 24 datasets of tracking data on penguins (three species, seven colonies, and three different breeding stages-incubation, brood, and crèche). RESULTS: We identified five new marine IBAs for seabirds in the study area, estimated to hold ca. 600,000 adult penguins. MAIN CONCLUSIONS: The results demonstrate the efficacy of a new method for the designation of a network of marine IBAs in Antarctic waters for penguins based on tracking data, which can contribute to an evidence-based, precautionary, management framework for krill fisheries.

20.
J Vasc Surg ; 68(3): 843-848, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29615350

RESUMO

OBJECTIVE: Almost two million individuals are undergoing renal replacement therapy worldwide, with hemodialysis being the common form. Many factors influence the primary patency of an arteriovenous fistula (AVF), including vessel size, fistula flow rates, cannulation practice, and thrombotic tendencies. Excess dilation of the AVF, resulting in the development of a megafistula, is a complication that can result in a need for AVF revision and subsequent failure. METHODS: The charts of patients who underwent autogenous AVF revision because of the development of a megafistula with aneurysmectomy and vein transposition by a single surgeon during a 7-year period from 2009 through 2016 were reviewed. A technique is described in which after aneurysmorrhaphy, the repaired venous component of the AVF is transposed through a new tunnel while the vein is rotated 90 degrees. This allows the AVF to be accessed immediately, making placement of a tunneled dialysis catheter unnecessary. RESULTS: There were 102 patients included in the study, with follow-up ranging from 7 to 95 months. In our cohort, 92 of the 102 revised AVFs (90.2%) maintained primary functional patency. Of the 102 patients who underwent this revision technique, there were 10 fistulas that subsequently failed after a mean of 29 months. There were only seven patients who experienced recurrent fistula dilation requiring repeated aneurysmectomy. CONCLUSIONS: We describe a technique for management of the development of a megafistula that uses only autogenous tissue and, perhaps most important, eliminates the need for temporary dialysis catheter placement.


Assuntos
Aneurisma/cirurgia , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Diálise Renal , Terapia de Salvação , Extremidade Superior/irrigação sanguínea , Grau de Desobstrução Vascular , Aneurisma/etiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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