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1.
New Phytol ; 241(4): 1447-1463, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37984063

RESUMO

The threat of rising global temperatures may be especially pronounced for low-latitude, lowland plant species that have evolved under stable climatic conditions. However, little is known about how these species may acclimate to elevated temperatures. Here, we leveraged a strong, steep thermal gradient along a natural geothermal river to assess the ability of woody plants in the Amazon to acclimate to elevated air temperatures. We measured leaf traits in six common tropical woody species along the thermal gradient to investigate whether individuals of these species: acclimate their thermoregulatory traits to maintain stable leaf temperatures despite higher ambient temperatures; acclimate their photosynthetic thermal tolerances to withstand hotter leaf temperatures; and whether acclimation is sufficient to maintain stable leaf thermal safety margins (TSMs) across different growth temperatures. Individuals of three species acclimated their thermoregulatory traits, and three species increased their thermal tolerances with growth temperature. However, acclimation was generally insufficient to maintain constant TSMs. Notwithstanding, leaf health was generally consistent across growth temperatures. Acclimation in woody Amazonian plants is generally too weak to maintain TSMs at high growth temperatures, supporting previous findings that Amazonian plants will be increasingly vulnerable to thermal stress as temperatures rise.


Assuntos
Aclimatação , Temperatura Alta , Humanos , Temperatura , Plantas , Folhas de Planta
2.
BMC Pediatr ; 22(1): 428, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35854276

RESUMO

BACKGROUND: Evidence suggests that the interactive effects of physical activity, screen-time and sleep are stronger than independent effects of these behaviors on pediatric obesity. However, this hypothesis has not been fully examined among samples of young school-aged children. The aim of this study is to determine the association of weight status with meeting the physical activity, screen-time, and sleep guidelines, independently and concurrently, among 2nd grade children. METHODS: The Texas School Physical Activity and Nutrition Project collected parent-reported physical activity, screen-time, and sleep, and measured body height and weight on a statewide representative weighted sample (n = 320,005) of children. Weighted multivariable logistic regressions were used to assess associations of weight status (classified using age- and sex-specific body weight [kg]/height [m]2, based on International Obesity Task Force cutoffs) with meeting the physical activity, screen-time, and sleep guidelines, while controlling for relevant covariates (age, sex, race/ethnicity, comorbidities etc.). RESULTS: A greater proportion of healthy weight children (9.9%) met the physical activity, screen-time, and sleep guidelines concurrently compared to children who are thin (3.3%), or children with overweight (5.7%), obese (3.5%), and morbid obesity (1.0%). Children who were thin (adjusted odds ratio [aOR]:0.40, 95% confidence interval [CI]: 0.10, 1.50), overweight (aOR = 0.75, CI: 0.33, 1.70), obese (aOR = 0.53, CI: 0.15, 1.81), and morbidly obese (aOR = 0.10, CI: 0.02, 0.28) had lower odds of concurrently meeting the guidelines compared to children with healthy weight. CONCLUSIONS: Among this representative sample of Texas children, weight status was associated with meeting physical activity, screen-time, and sleep guidelines. Future studies should aim to evaluate causal relations between these behaviors and weight status.


Assuntos
Obesidade Mórbida , Sobrepeso , Criança , Estudos Transversais , Exercício Físico , Feminino , Humanos , Masculino , Obesidade Mórbida/complicações , Sobrepeso/epidemiologia , Sobrepeso/etiologia , Sono , Texas/epidemiologia
3.
Environ Monit Assess ; 194(7): 493, 2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35690674

RESUMO

Microcystin (MC) is a toxic secondary metabolite produced by select cyanobacteria that threatens aquatic and terrestrial organisms over a diverse range of freshwater systems. To assess the relationship between environmental parameters and MC, researchers frequently utilize correlational analyses. This statistical methodology has proved useful when summarizing complex water quality monitoring datasets, but the correlations between select parameters and MC have been documented to vary widely across studies and systems. Such variation within the peer-reviewed literature leaves uncertainty for resource managers when developing a MC monitoring program. The objective of this research is to determine if correlational analyses between environmental parameters and MC are helpful to resource managers desiring to understand the drivers of MC. Environmental (i.e., physical, chemical, and biological) and MC correlation data were retrieved from an estimated 2,643 waterbodies (largely from the north temperate region) and synthesized using a Fisher's z meta-analysis. Common water quality parameters, such as chlorophyll, temperature, and pH, were positively correlated with MC, while transparency was negatively correlated. Interestingly, 12 of the 15 studied nitrogen parameters, including total nitrogen, were not significantly correlated with MC. In contrast, three of the four studied phosphorus parameters, including total phosphorus, were positively related to MC. Results from this synthesis quantitatively reinforces the usefulness of commonly measured environmental parameters to monitor for conditions related to MC occurrence; however, correlational analyses by themselves are often ineffective and considering what role a parameter plays in the ecology of cyanobacterial blooms in addition to MC production is vital.


Assuntos
Cianobactérias , Microcistinas , Cianobactérias/metabolismo , Ecossistema , Monitoramento Ambiental/métodos , Água Doce/análise , Lagos/química , Microcistinas/análise , Nitrogênio/análise , Fósforo/análise , Qualidade da Água
4.
Brain Inj ; 35(14): 1702-1710, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34894933

RESUMO

PRIMARY OBJECTIVE: Traumatic brain injury (TBI) is a signature wound of recent Unites States military conflicts. The National Intrepid Center of Excellence (NICoE) has demonstrated that interdisciplinary care is effective for active-duty military personnel with TBI and related psychological health conditions. This paper details how the Marcus Institute for Brain Health (MIBH), established in 2017 as an Integrated Practice Unit (IPU), is founded on the NICoE model and is dedicated to interdisciplinary care for Veterans with persistent symptoms due to TBI and psychological comorbidities. RESEARCH DESIGN: A highly integrated group of clinicians from diverse disciplines combine their expertise to offer comprehensive evaluation, intensive outpatient treatment, and program outcomes evaluation. METHODS AND PROCEDURES: The role of each discipline in the provision of care, and the regular interaction of all clinicians, are delineated. A strong connection to academic medicine is maintained so that clinical research and education complement patient care. MAIN OUTCOMES AND RESULTS: Over three hundred veterans and family members have received treatment at the MIBH. Program evaluation is underway. CONCLUSIONS: As the understanding of TBI and related psychological conditions continues its rapid evolution, the expert interdisciplinary care at the MIBH has great promise as a Veteran counterpart of the NICoE.


Assuntos
Lesões Encefálicas Traumáticas , Militares , Transtornos de Estresse Pós-Traumáticos , Veteranos , Encéfalo , Lesões Encefálicas Traumáticas/psicologia , Lesões Encefálicas Traumáticas/terapia , Comorbidade , Humanos , Militares/psicologia , Transtornos de Estresse Pós-Traumáticos/terapia , Veteranos/psicologia
5.
Brain Inj ; 35(10): 1162-1167, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34554040

RESUMO

OBJECTIVE: Estimate the probability of met and unmet post-acute rehabilitative needs among pediatric patients with moderate to severe traumatic brain injury (TBI). PARTICIPANTS: One hundred and thirty children who received acute and post-acute rehabilitative services at a hospital for children. METHODS: Prospective, observational study. Recommended service needs (1. Medical, 2. Psychological, 3. Cognitive/Educational, 4. Medically Based Therapies, 5. Community/Caregiver/Family Support) were collected at discharge and 1, 6, 12, and 18 months post-injury. Probabilities were estimated using nonlinear logistic regression models. The impact of age at discharge was also assessed. RESULTS: Over time, the estimated probability of need for Medical, Medically Based Therapies, and Cognitive/Educational services were consistently high. Whereas unmet need for Medical and Medically Based Therapies were low, unmet need for Cognitive/Educational services were relatively high. Need for Psychological and Community/Caregiver/Family Support services increased in the months post-discharge, as did the probability of unmet need. Older age at discharge was associated with need for Psychological and Community/Caregiver Family Support services. CONCLUSIONS: Findings support the long-term monitoring of need for Psychological and Community/Caregiver/Family Support services among children with moderate to severe TBI. Future research to explore the etiology of unmet needs is warranted.


Assuntos
Assistência ao Convalescente , Lesões Encefálicas Traumáticas , Idoso , Criança , Necessidades e Demandas de Serviços de Saúde , Humanos , Alta do Paciente , Estudos Prospectivos
6.
Lupus ; 29(5): 474-481, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32233733

RESUMO

BACKGROUND: Systemic lupus erythematous (SLE) is a systemic autoimmune/inflammatory condition. Approximately 15-20% of patients develop symptoms before their 18th birthday and are diagnosed with juvenile-onset SLE (JSLE). Gender distribution, clinical presentation, disease courses and outcomes vary significantly between JSLE patients and individuals with adult-onset SLE. This study aimed to identify age-specific clinical and/or serological patterns in JSLE patients enrolled to the UK JSLE Cohort Study. METHODS: Patient records were accessed and grouped based on age at disease-onset: pre-pubertal (≤7 years), peri-pubertal (8-13 years) and adolescent (14-18 years). The presence of American College of Rheumatology (ACR) classification criteria, laboratory results, disease activity [British Isles Lupus Assessment Group (BILAG) and Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2 K) scores] and damage [Systemic Lupus International Collaborating Clinics (SLICC) damage index] were evaluated at diagnosis and last follow up. RESULTS: A total of 418 JSLE patients were included in this study: 43 (10.3%) with pre-pubertal disease onset; 240 (57.4%) with peri-pubertal onset and 135 (32.3%) were diagnosed during adolescence. At diagnosis, adolescent JSLE patients presented with a higher number of ACR criteria when compared with pre-pubertal and peri-pubertal patients [pBILAG2004 scores: 9(4-20] vs. 7(3-13] vs. 7(3-14], respectively, p = 0.015] with increased activity in the following BILAG domains: mucocutaneous (p = 0.025), musculoskeletal (p = 0.029), renal (p = 0.027) and cardiorespiratory (p = 0.001). Furthermore, adolescent JSLE patients were more frequently ANA-positive (p = 0.034) and exhibited higher anti-dsDNA titres (p = 0.001). Pre-pubertal individuals less frequently presented with leukopenia (p = 0.002), thrombocytopenia (p = 0.004) or low complement (p = 0.002) when compared with other age groups. No differences were identified in disease activity (pBILAG2004 score), damage (SLICC damage index) and the number of ACR criteria fulfilled at last follow up. CONCLUSIONS: Disease presentations and laboratory findings vary significantly between age groups within a national cohort of JSLE patients. Patients diagnosed during adolescence exhibit greater disease activity and "classic" autoantibody, immune cell and complement patterns when compared with younger patients. This supports the hypothesis that pathomechanisms may vary between patient age groups.


Assuntos
Progressão da Doença , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/patologia , Índice de Gravidade de Doença , Adolescente , Idade de Início , Criança , Técnicas de Laboratório Clínico , Estudos de Coortes , Feminino , Humanos , Masculino , Fatores Sexuais , Reino Unido
7.
Int Endod J ; : 1050-1061, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32333794

RESUMO

AIMS: To assess the reporting quality of recently published randomised controlled trial (RCT) abstracts in Endodontics, to investigate factors associated with reporting quality, and to evaluate the existence and characteristics of spin. Spin refers to reporting strategies that distort study results and misguide readers. METHODOLOGY: The PubMed database was searched to identify abstracts of RCTs in the field of Endodontics published during 2017 to 2018. Two authors assessed the reporting quality of each included abstract using the original 16-item CONSORT for Abstracts checklist, with the overall quality score (OQS, range: 0 to 16) being the primary outcome measure. For each individual item, a score of '1' was given if it was described adequately, and '0' if the description was inadequate. Linear regression analyses were conducted to identify factors associated with reporting quality. For the evaluation of spin, two authors selected parallel-group RCTs with a nonsignificant primary outcome from the included abstracts, and evaluated independently the existence and characteristics of spin among these abstracts. RESULTS: A total of 162 abstracts were included for assessment of reporting, for which the mean OQS was 3.97 (SD, 1.30; 95 % CI, 3.77 to 4.17). According to multivariable analysis, origin from Europe (P=0.001) and reporting of the exact P value (P=0.020) were significantly associated with better reporting. Forty abstracts with statistically nonsignificant results for their primary outcome were included for spin evaluation, among which 34 (85.0%) had at least one type of spin. Thirty-two abstracts (94.1%) had spin in their conclusions section, and six abstracts (17.6%) had spin in the results section. CONCLUSIONS: The reporting quality of RCT abstracts in Endodontics needs to be improved. The occurrence rate of spin in the sample of abstracts of RCTs in the field of Endodontics was high. Relevant stakeholders are recommended to be familiar with the CONSORT for Abstracts guideline and develop active strategies to ensure its implementation.

8.
Lupus ; 28(5): 613-620, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30871425

RESUMO

BACKGROUND: Juvenile-onset systemic lupus erythematosus (JSLE) is more severe than adult-onset disease, including more lupus nephritis (LN). Despite differences in phenotype/pathogenesis, treatment is based upon adult trials. This study aimed to compare treatment response, damage accrual, time to inactive LN and subsequent flare, in JSLE LN patients treated with mycophenolate mofetil (MMF) versus intravenous cyclophosphamide (IVCYC). METHODS: UK JSLE Cohort Study participants, ≤16 years at diagnosis, with ≥4 American College of Rheumatology criteria for SLE, with class III or IV LN, were eligible. Mann-Whitney U tests, Fisher's exact test and Chi-squared tests were utilized for statistical analysis. RESULTS: Of the patients, 34/51 (67%) received MMF, and 17/51 (33%) received IVCYC. No significant differences were identified at 4-8 and 10-14 months post-renal biopsy and last follow-up, in terms of renal British Isles Lupus Assessment Grade scores, urine albumin/creatinine ratio, serum creatinine, ESR, anti-dsDNA antibody, C3 levels and patient/physician global scores. Standardized Damage Index scores did not differ between groups at 13 months or at last follow-up. Inactive LN was attained 262 (141-390) days after MMF treatment, and 151 (117-305) days following IVCYC ( p = 0.17). Time to renal flare was 451 (157-1266) days for MMF, and 343 (198-635) days for IVCYC ( p = 0.47). CONCLUSION: This is the largest study to date investigating induction treatments for proliferative LN in children, demonstrating comparability of MMF and IVCYC.


Assuntos
Ciclofosfamida/uso terapêutico , Imunossupressores/uso terapêutico , Nefrite Lúpica/tratamento farmacológico , Ácido Micofenólico/uso terapêutico , Administração Intravenosa , Adolescente , Idade de Início , Criança , Estudos de Coortes , Feminino , Humanos , Rim/patologia , Masculino , Indução de Remissão , Índice de Gravidade de Doença , Resultado do Tratamento , Reino Unido
9.
Space Weather ; 16(11): 1644-1667, 2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-32021590

RESUMO

In this paper we present an assessment of the status of models of the global Solar Wind in the inner heliosphere. We limit our discussion to the class of models designed to provide solar wind forecasts, excluding those designed for the purpose of testing physical processes in idealized configurations. In addition, we limit our discussion to modeling of the 'ambient' wind in the absence of coronal mass ejections. In this assessment we cover use of the models both in forecast mode and as tools for scientific research. We present a brief history of the development of these models, discussing the range of physical approximations in use. We discuss the limitations of the data inputs available to these models and its impact on their quality. We also discuss current model development trends.

10.
Lupus ; 26(12): 1285-1290, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28361566

RESUMO

Objectives The Systemic Lupus International Collaborating Clinics (SLICC) group proposed revised classification criteria for systemic lupus erythematosus (SLICC-2012 criteria). This study aimed to compare these criteria with the well-established American College of Rheumatology classification criteria (ACR-1997 criteria) in a national cohort of juvenile-onset systemic lupus erythematosus (JSLE) patients and evaluate how patients' classification criteria evolved over time. Methods Data from patients in the UK JSLE Cohort Study with a senior clinician diagnosis of probable evolving, or definite JSLE, were analyzed. Patients were assessed using both classification criteria within 1 year of diagnosis and at latest follow up (following a minimum 12-month follow-up period). Results A total of 226 patients were included. The SLICC-2012 was more sensitive than ACR-1997 at diagnosis (92.9% versus 84.1% p < 0.001) and after follow up (100% versus 92.0% p < 0.001). Most patients meeting the SLICC-2012 criteria and not the ACR-1997 met more than one additional criterion on the SLICC-2012. Conclusions The SLICC-2012 was better able to classify patients with JSLE than the ACR-1997 and did so at an earlier stage in their disease course. SLICC-2012 should be considered for classification of JSLE patients in observational studies and clinical trial eligibility.


Assuntos
Lúpus Eritematoso Sistêmico/classificação , Reumatologia , Adolescente , Idade de Início , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/fisiopatologia , Masculino
11.
Sol Phys ; 292(5): 69, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-32055078

RESUMO

Effective space-weather prediction and mitigation requires accurate forecasting of near-Earth solar-wind conditions. Numerical magnetohydrodynamic models of the solar wind, driven by remote solar observations, are gaining skill at forecasting the large-scale solar-wind features that give rise to near-Earth variations over days and weeks. There remains a need for accurate short-term (hours to days) solar-wind forecasts, however. In this study we investigate the analogue ensemble (AnEn), or "similar day", approach that was developed for atmospheric weather forecasting. The central premise of the AnEn is that past variations that are analogous or similar to current conditions can be used to provide a good estimate of future variations. By considering an ensemble of past analogues, the AnEn forecast is inherently probabilistic and provides a measure of the forecast uncertainty. We show that forecasts of solar-wind speed can be improved by considering both speed and density when determining past analogues, whereas forecasts of the out-of-ecliptic magnetic field [ B N ] are improved by also considering the in-ecliptic magnetic-field components. In general, the best forecasts are found by considering only the previous 6 - 12 hours of observations. Using these parameters, the AnEn provides a valuable probabilistic forecast for solar-wind speed, density, and in-ecliptic magnetic field over lead times from a few hours to around four days. For B N , which is central to space-weather disturbance, the AnEn only provides a valuable forecast out to around six to seven hours. As the inherent predictability of this parameter is low, this is still likely a marked improvement over other forecast methods. We also investigate the use of the AnEn in forecasting geomagnetic indices Dst and Kp. The AnEn provides a valuable probabilistic forecast of both indices out to around four days. We outline a number of future improvements to AnEn forecasts of near-Earth solar-wind and geomagnetic conditions.

12.
Acta Paediatr ; 105(9): e396-405, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27149074

RESUMO

AIM: To identify additional risk factors other than asphyxia and hypothermia in newborns developing subcutaneous fat necrosis (SCFN). METHODS: We conducted a prospective cohort study of all term asphyxiated newborns treated with hypothermia from 2008 to 2015. The presence and location of SCFN were recorded at the time of discharge or at follow-up visits. To identify the risk factors for developing SCFN, we compared the perinatal characteristics of those newborns who developed SCFN with those who did not. RESULTS: The newborns developing SCFN had significantly higher birthweights compared with those newborns who did not develop SCFN. Among the newborns with a birthweight equal or superior to the 90th percentile, those who developed SCFN had a significantly higher use of inotropic support and higher maximum troponin levels during their initial hospitalisation. CONCLUSION: A higher birthweight represented an independent risk factor for developing SCFN in asphyxiated newborns treated with hypothermia. When macrosomia is present, other risk factors related to haemodynamic instability during the initial hospitalisation may also increase the risk of developing SCFN.


Assuntos
Asfixia Neonatal/complicações , Necrose Gordurosa/etiologia , Macrossomia Fetal/complicações , Hipotermia Induzida/efeitos adversos , Asfixia Neonatal/terapia , Necrose Gordurosa/epidemiologia , Feminino , Hemodinâmica , Humanos , Incidência , Recém-Nascido , Masculino , Estudos Prospectivos , Quebeque/epidemiologia , Fatores de Risco
13.
J Radiol Prot ; 34(2): 469-84, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24894330

RESUMO

In the UK, as elsewhere, there is potential to improve how radiological challenges are addressed through improvement in, or development of, a strong radiation protection (RP) safety culture. In preliminary work in the UK, two areas have been identified as having a strong influence on UK society: the healthcare and nuclear industry sectors. Each has specific challenges, but with many overlapping common factors. Other sectors will benefit from further consideration.In order to make meaningful comparisons between these two principal sectors, this paper is primarily concerned with cultural aspects of RP in the working environment and occupational exposures rather than patient doses.The healthcare sector delivers a large collective dose to patients each year, particularly for diagnostic purposes, which continues to increase. Although patient dose is not the focus, it must be recognised that collective patient dose is inevitably linked to collective occupational exposure, especially in interventional procedures.The nuclear industry faces major challenges as work moves from operations to decommissioning on many sites. This involves restarting work in the plants responsible for the much higher radiation doses of the 1960/70s, but also performing tasks that are considerably more difficult and hazardous than those original performed in these plants.Factors which influence RP safety culture in the workplace are examined, and proposals are considered for a series of actions that may lead to an improvement in RP culture with an associated reduction in dose in many work areas. These actions include methods to improve knowledge and awareness of radiation safety, plus ways to influence management and colleagues in the workplace. The exchange of knowledge about safety culture between the nuclear industry and medical areas may act to develop RP culture in both sectors, and have a wider impact in other sectors where exposures to ionising radiations can occur.


Assuntos
Setor de Assistência à Saúde/organização & administração , Promoção da Saúde/organização & administração , Centrais Nucleares , Cultura Organizacional , Guias de Prática Clínica como Assunto , Proteção Radiológica/normas , Gestão da Segurança/organização & administração , Brasil , França , Fidelidade a Diretrizes , Reino Unido
14.
J Hosp Infect ; 145: 59-64, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38141666

RESUMO

BACKGROUND: Mandatory mask-wearing policies were one of several measures employed to reduce hospital-acquired SARS-CoV-2 infection throughout the pandemic. Many nations have removed healthcare mask mandates, but there remains a risk of new SARS-CoV-2 variants or epidemics of other respiratory viruses. AIM: To demonstrate the impact of removing the healthcare mask mandate. METHODS: SARS-CoV-2 infections were analysed in a large teaching hospital for 40 weeks in 2022 using a controlled interrupted time-series design. The intervention was the removal of a staff/visitor surgical mask-wearing policy for the most wards at week 26 (intervention group) with a subset of specific wards retaining the mask policy (control group). The hospital-acquired SARS-CoV-2 infection rate was adjusted by the underlying community infection rate. FINDINGS: In the context of a surge in SARS-CoV-2 infection, removal of the mask mandate for staff/visitors was not associated with a statistically significant change in the rate of nosocomial SARS-CoV-2 infection in the intervention group (incidence rate ratio: 1.105; 95% confidence interval: 0.523-2.334; P = 0.79) and there was no post-intervention trend (1.013; 0.932-1.100; P = 0.76) to suggest a delayed effect. The control group also showed no immediate or delayed change in infection rate. CONCLUSION: No evidence was found that removal of a staff/visitor mask-wearing policy had a significant effect on the rate of hospital-acquired SARS-CoV-2 infection. This does not demonstrate that masks were ineffective through the pandemic, but provides some objective evidence to justify the removal of healthcare mask mandates once there was widespread immunity and reduced disease severity.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2 , Pandemias/prevenção & controle , Máscaras , Hospitais
15.
Front Cardiovasc Med ; 11: 1376101, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628313

RESUMO

Introduction: Heart transplant remains the gold standard treatment for patients with advanced heart failure. However, the list of patients waiting for a heart transplant continues to increase. We have developed a portable hypothermic oxygenated machine perfusion device, the VP.S ENCORE®, to extend the allowable preservation time. The purpose of this study was to test the efficacy of the VP.S. ENCORE® using deceased donors derived hearts. Methods: Hearts from brain-dead donors not utilized for transplant (n = 11) were offered for research from the Texas Organ Sharing Alliance (TOSA), South and Central Texas' Organ Procurement Organization (OPO) and were preserved in the VP.S ENCORE® for 4 (n = 2), 6 (n = 3), and 8 (n = 3) hours or were kept in static cold storage (SCS) (n = 3). After preservation, the hearts were placed in an isolated heart Langendorff model for reperfusion and evaluated for cardiac function. Results: The mean donor age was 37.82 ± 12.67 with the youngest donor being 19 and the oldest donor being 58 years old. SCS hearts mean weight gain (%) was -1.4 ± 2.77, while perfused at 4 h was 5.6 ± 6.04, perfused at 6 h 2.1 ± 6.04, and 8 h was 7.2 ± 10.76. Venous and arterial lactate concentrations were less than 2.0 mmol/L across all perfused hearts. Left ventricular contractility (+dPdT, mmHg/s) for 4 h (1,214 ± 1,064), 6 (1,565 ± 141.3), and 8 h (1,331 ± 403.6) were within the range of healthy human heart function. Thus, not significant as compared to the SCS group (1,597 ± 342.2). However, the left ventricular relaxation (mmHg/s) was significant in 6-hour perfused heart (p < 0.05) as compared to SCS. Gene expression analysis of inflammation markers (IL-6, IL-1ß) showed no significant differences between SCS and perfused hearts, but a 6-hour perfusion led to a downregulated expression of these markers. Discussion: The results demonstrate that the VP.S ENCORE® device enhances cardiac viability and exhibits comparable cardiac function to a healthy heart. The implications of these findings suggest that the VP.S ENCORE® could introduce a new paradigm in the field of organ preservation, especially for marginal hearts.

16.
Nat Genet ; 18(3): 271-5, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9500551

RESUMO

The placenta and cardiovascular system are the first organ systems to form during mammalian embryogenesis. We show here that a single gene is critical for development of both. The Hand1 gene, previously called Hxt, eHAND and Thing1, encodes a basic helix-loop-helix (bHLH) transcription factor that starts to be expressed during pre-implantation development. After implantation, Hand1 expression is restricted to placental trophoblast cells and later to embryonic cardiac and neural crest cells. We generated Hand1-null mutant mice by gene targetting. Homozygous mutant embryos arrested by embryonic day (E) 7.5 of gestation with defects in trophoblast giant cell differentiation. This early mortality could be rescued by aggregation of mutant embryos with wild-type tetraploid embryos, which contribute wild-type cells to the trophoblast, but not the embryo. By E10.5, however, the Hand1-null fetuses derived from tetraploid chimaeras died due to cardiac failure. Their heart tubes showed abnormal looping and ventricular myocardial differentiation. Therefore, Hand1 is essential for differentiation of both trophoblast and cardiomyocytes, which are embryologically distinct cell lineages.


Assuntos
Proteínas de Ligação a DNA/genética , Coração/embriologia , Miocárdio/patologia , Placenta/fisiologia , Proteínas de Saccharomyces cerevisiae , Fatores de Transcrição/genética , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Diferenciação Celular/genética , Proteínas de Ligação a DNA/metabolismo , Implantação do Embrião , Embrião de Mamíferos/metabolismo , Embrião de Mamíferos/patologia , Feminino , Morte Fetal/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Marcadores Genéticos , Células Gigantes , Heterozigoto , Homozigoto , Masculino , Camundongos , Camundongos Endogâmicos , Camundongos Mutantes , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Motores Moleculares , Placenta/patologia , Gravidez , Fatores de Transcrição/metabolismo , Trofoblastos/patologia
17.
Appl Neuropsychol Child ; : 1-9, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36809228

RESUMO

This study aimed to describe the 24-hour composition of movement behaviors, including sleep, sedentary behavior, and physical activity (PA), among pediatric sports-related concussion (SRC) patients over their recovery period, assess the association between movement compositions and recovery time, and understand feasibility of 24-hour accelerometry in the study population. A cohort of 50 pediatric SRC patients were asked to wear a wrist-worn accelerometer continuously for the duration of their recovery. Among all enrolled participants, the sample was primarily 14 or 15 years of age (65%), female (55%), and recovered in under 28 days (88%). Accelerometer compliance was moderate; 35 participants (70%) were compliant with the protocol. Compositional analysis was used to address time-use objectives in 33 participants who provided adequate data for inclusion. Overall, participants spent an average of 50% of their 24-hour day sedentary, 33% sleeping, 11% in light intensity PA, and 6% in moderate or vigorous intensity PA. The 24-hour composition of movement behaviors was not associated with recovery time (p = .09-.99). However, the limited sample size may have contributed to null findings. Given recent evidence supporting the effects of sedentary behavior and PA on concussion recovery, future studies should aim to further validate these findings in a larger sample.

18.
Environ Sci Pollut Res Int ; 30(15): 43991-44005, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36670225

RESUMO

Harmful cyanobacterial blooms plague reservoirs and lakes used for a variety of purposes, such as recreation and drinking water. Chemical controls are frequently used to mitigate the occurrence of cyanobacterial blooms given that many are fast-acting and effective at reducing cyanobacterial abundance. Recent research has identified hydrogen peroxide (H2O2) as an environmentally friendly alternative to algaecides that have typically been used, such as copper sulfate. To build on past studies, these experiments sought to further understand how well H2O2 treatments reduce cyanobacteria in complex eutrophic conditions, as well as to assess treatment effects on a non-target phytoplankter, a green alga. We assessed the effectiveness of H2O2 (at treatments of 2-16 mg L-1) under varying environmental conditions in a controlled laboratory setting, including (1) dissolved organic matter (DOM) concentrations (humic acid; 0-60 mg L-1), (2) temperature (20, 25, and 32 °C), and (3) initial algal biomass (chlorophyll-a; 82-371 µg L-1). In contrast to our expectations, neither DOM concentration nor temperature meaningfully impacted the effectiveness of H2O2 at reducing cyanobacteria. However, initial algal biomass as well as H2O2 treatment dose greatly influenced the effectiveness of the algaecide on cyanobacteria. Treatments of ≥ 8 mg H2O2 L-1 on algal biomass were significantly buffered with higher DOM and lower temperature, and the biological significance of these findings should be explored further. Across all experiments, H2O2 concentrations of 0.03-0.12 mg H2O2 L-1 µg chlorophyll L-1 were effective at significantly reducing cyanobacteria with varying effects on algal biomass. Thus, water resource managers are encouraged to consider how ambient levels of phytoplankton biomass may affect the ability of H2O2 to control cyanobacterial blooms prior to treatment.


Assuntos
Cianobactérias , Peróxido de Hidrogênio , Peróxido de Hidrogênio/farmacologia , Matéria Orgânica Dissolvida , Temperatura , Lagos/microbiologia , Clorofila/farmacologia , Eutrofização , Proliferação Nociva de Algas
19.
J Gastrointest Surg ; 27(11): 2474-2483, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37740146

RESUMO

BACKGROUND: Biopsy of suspected pancreatic cancer (PDAC) in surgical candidates is informative however not always necessary. Biopsies impact treatment options as histological diagnosis are presently required for neo-adjuvant therapy, but not surgical resection. We explored the impact of pursuing tissue diagnosis by endoscopic ultrasound (EUS) biopsy on time to treatment in patients with resectable and borderline resectable PDAC. METHODS: A retrospective review of surgical patients with ultimately proven PDAC was performed (2011-2021). Milestone dates (cancer suspected, biopsy(ies), surgical or neo-adjuvant treatment) were collected. Mann-Whitney-Wilcoxon tests, Pearson's chi-squared tests, Fisher's exact tests, linear regressions, and Cox proportional hazard models were used for data analysis. RESULTS: Among 131 resectable and 58 borderline resectable patients, the borderline resectable group underwent more biopsies (1.2 vs 0.7, p < 0.0001), were more likely to undergo biopsy at tertiary care centers (67.2% vs 30.5%, p < 0.0001), and trended toward longer time to treatment (49 vs 44 days, p = 0.070). Significant increases in days to treatment were seen in patients with Black race (29 days, p = 0.0002) and Medicare insurance (22 days, p = 0.038) and no biopsies at a tertiary care center (10 days, p = 0.039). After adjusting for covariates, additional biopsies significantly delayed treatment (1 biopsy: 21 days, p = 0.0001; 2 biopsies: 44 days, p < 0.0001; 3 biopsies: 68 days, p < 0.0001). CONCLUSIONS: EUS biopsy significantly impacts time between suspicion and treatment of PDAC. This may be exacerbated by clinical practices increasingly favoring neo-adjuvant therapy that necessitates biopsy-proven disease. Time to treatment may also be impacted by access to tertiary centers and racial disparities.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Idoso , Humanos , Estados Unidos , Carcinoma Ductal Pancreático/cirurgia , Medicare , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas/diagnóstico , Biópsia , Estudos Retrospectivos
20.
JCO Oncol Pract ; 19(10): 882-887, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37647578

RESUMO

PURPOSE: The standard of care in resectable and borderline resectable pancreatic ductal adenocarcinoma (PDAC) has evolved to include neoadjuvant treatment before surgical resection. Current guidelines call for obtaining histologic tissue diagnosis via endoscopic ultrasound fine-needle aspiration before administration of neoadjuvant therapy, which differ from guidelines discouraging delay in surgical resection for a biopsy. MATERIALS AND METHODS: Whether to proceed with treatment before a biopsy confirms that malignancy is a nuanced decision and includes considerations of physical and psychological risks entailed in both pursuing and forgoing a biopsy. RESULTS: Accuracy of imaging and biopsy results, the presence of contributing clinical signs/symptoms, and the existing precedents of considering biopsies as waivable such as in scenarios with high clinical suspicion and primary surgical resection. CONCLUSION: When considering the aspects of ethical medical practice including beneficence (doing good), nonmaleficence (avoiding harm), autonomy (allowing patients to make decisions about their care), and utilitarianism (doing the most good for the most people), analysis of whether guidelines guiding biopsies should continue to differ between resection and neoadjuvant treatments in PDAC is prudent.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/patologia , Terapia Neoadjuvante , Biópsia
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