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BACKGROUND/AIMS: Stepped-wedge cluster randomized trials tend to require fewer clusters than standard parallel-arm designs due to the switches between control and intervention conditions, but there are no recommendations for the minimum number of clusters. Trials randomizing an extremely small number of clusters are not uncommon, but the justification for small numbers of clusters is often unclear and appropriate analysis is often lacking. In addition, stepped-wedge cluster randomized trials are methodologically more complex due to their longitudinal correlation structure, and ignoring the distinct within- and between-period intracluster correlations can underestimate the sample size in small stepped-wedge cluster randomized trials. We conducted a review of published small stepped-wedge cluster randomized trials to understand how and why they are used, and to characterize approaches used in their design and analysis. METHODS: Electronic searches were used to identify primary reports of full-scale stepped-wedge cluster randomized trials published during the period 2016-2022; the subset that randomized two to six clusters was identified. Two reviewers independently extracted information from each report and any available protocol. Disagreements were resolved through discussion. RESULTS: We identified 61 stepped-wedge cluster randomized trials that randomized two to six clusters: median sample size (Q1-Q3) 1426 (420-7553) participants. Twelve (19.7%) gave some indication that the evaluation was considered a "preliminary" evaluation and 16 (26.2%) recognized the small number of clusters as a limitation. Sixteen (26.2%) provided an explanation for the limited number of clusters: the need to minimize contamination (e.g. by merging adjacent units), limited availability of clusters, and logistical considerations were common explanations. Majority (51, 83.6%) presented sample size or power calculations, but only one assumed distinct within- and between-period intracluster correlations. Few (10, 16.4%) utilized restricted randomization methods; more than half (34, 55.7%) identified baseline imbalances. The most common statistical method for analysis was the generalized linear mixed model (44, 72.1%). Only four trials (6.6%) reported statistical analyses considering small numbers of clusters: one used generalized estimating equations with small-sample correction, two used generalized linear mixed model with small-sample correction, and one used Bayesian analysis. Another eight (13.1%) used fixed-effects regression, the performance of which requires further evaluation under stepped-wedge cluster randomized trials with small numbers of clusters. None used permutation tests or cluster-period level analysis. CONCLUSION: Methods appropriate for the design and analysis of small stepped-wedge cluster randomized trials have not been widely adopted in practice. Greater awareness is required that the use of standard sample size calculation methods can provide spuriously low numbers of required clusters. Methods such as generalized estimating equations or generalized linear mixed models with small-sample corrections, Bayesian approaches, and permutation tests may be more appropriate for the analysis of small stepped-wedge cluster randomized trials. Future research is needed to establish best practices for stepped-wedge cluster randomized trials with a small number of clusters.
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BACKGROUND/AIMS: The stepped-wedge cluster randomized trial (SW-CRT), in which clusters are randomized to a time at which they will transition to the intervention condition - rather than a trial arm - is a relatively new design. SW-CRTs have additional design and analytical considerations compared to conventional parallel arm trials. To inform future methodological development, including guidance for trialists and the selection of parameters for statistical simulation studies, we conducted a review of recently published SW-CRTs. Specific objectives were to describe (1) the types of designs used in practice, (2) adherence to key requirements for statistical analysis, and (3) practices around covariate adjustment. We also examined changes in adherence over time and by journal impact factor. METHODS: We used electronic searches to identify primary reports of SW-CRTs published 2016-2022. Two reviewers extracted information from each trial report and its protocol, if available, and resolved disagreements through discussion. RESULTS: We identified 160 eligible trials, randomizing a median (Q1-Q3) of 11 (8-18) clusters to 5 (4-7) sequences. The majority (122, 76%) were cross-sectional (almost all with continuous recruitment), 23 (14%) were closed cohorts and 15 (9%) open cohorts. Many trials had complex design features such as multiple or multivariate primary outcomes (50, 31%) or time-dependent repeated measures (27, 22%). The most common type of primary outcome was binary (51%); continuous outcomes were less common (26%). The most frequently used method of analysis was a generalized linear mixed model (112, 70%); generalized estimating equations were used less frequently (12, 8%). Among 142 trials with fewer than 40 clusters, only 9 (6%) reported using methods appropriate for a small number of clusters. Statistical analyses clearly adjusted for time effects in 119 (74%), for within-cluster correlations in 132 (83%), and for distinct between-period correlations in 13 (8%). Covariates were included in the primary analysis of the primary outcome in 82 (51%) and were most often individual-level covariates; however, clear and complete pre-specification of covariates was uncommon. Adherence to some key methodological requirements (adjusting for time effects, accounting for within-period correlation) was higher among trials published in higher versus lower impact factor journals. Substantial improvements over time were not observed although a slight improvement was observed in the proportion accounting for a distinct between-period correlation. CONCLUSIONS: Future methods development should prioritize methods for SW-CRTs with binary or time-to-event outcomes, small numbers of clusters, continuous recruitment designs, multivariate outcomes, or time-dependent repeated measures. Trialists, journal editors, and peer reviewers should be aware that SW-CRTs have additional methodological requirements over parallel arm designs including the need to account for period effects as well as complex intracluster correlations.
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Projetos de Pesquisa , Humanos , Análise por Conglomerados , Ensaios Clínicos Controlados Aleatórios como Assunto , Simulação por Computador , Modelos Lineares , Tamanho da AmostraRESUMO
BACKGROUND: An alternative patient-centered appointment-based cardiac rehabilitation (CR) program has led to significant improvements in health outcomes for patients with cardiovascular disease. However, less is known about the effects of this approach on health-related quality of life (HRQoL), particularly for women. OBJECTIVE: We examined the effects of a patient-centered appointment-based CR program on HRQoL by sex and examined predictors of HRQoL improvements specifically for women. METHODS: Data were used from an urban single-center CR program at Yale New Haven Health (2012-2017). We collected information on patient demographics, socioeconomic status, and clinical characteristics. The Outcome Short-Form General Health Survey (SF-36) was used to measure HRQoL. We evaluated sex differences in SF-36 scores using t tests and used a multivariate linear regression model to examine predictors of improvements in HRQoL (total SF-36 score) for women. RESULTS: A total of 1530 patients with cardiovascular disease (23.7% women, 4.8% Black; mean age, 64 ± 10.8 years) were enrolled in the CR program. Women were more likely to be older, Black, and separated, divorced, or widowed. Although women had lower total SF-36 scores on CR entry, there was no statistically significant difference in CR adherence or total SF-36 score improvements between sexes. Women who were employed and those with chronic obstructive pulmonary disease were more likely to have improvements in total SF-36 scores. CONCLUSION: Both men and women participating in an appointment-based CR program achieved significant improvements in HRQoL. This approach could be a viable alternative to conventional CR to optimize secondary outcomes for patients.
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INTRODUCTION: Pragmatic research studies that include diverse dyads of persons living with dementia (PLWD) and their family caregivers are rare. METHODS: Community-dwelling dyads were recruited for a pragmatic clinical trial evaluating three approaches to dementia care. Four clinical trial sites used shared and site-specific recruitment strategies to enroll health system patients. RESULTS: Electronic health record (EHR) queries of patients with a diagnosis of dementia and engagement of their clinicians were the main recruitment strategies. A total of 2176 dyads were enrolled, with 80% recruited after the onset of the pandemic. PLWD had a mean age of 80.6 years (SD 8.5), 58.4% were women, and 8.8% were Hispanic/Latino, and 11.9% were Black/African American. Caregivers were mostly children of the PLWD (46.5%) or spouses/partners (45.2%), 75.8% were women, 9.4% were Hispanic/Latino, and 11.6% were Black/African American. DISCUSSION: Health systems can successfully enroll diverse dyads in a pragmatic clinical trial.
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Demência , Criança , Humanos , Feminino , Idoso de 80 Anos ou mais , Masculino , Demência/epidemiologia , Demência/terapia , Cuidadores , Vida IndependenteRESUMO
BACKGROUND: Injuries from falls are major contributors to complications and death in older adults. Despite evidence from efficacy trials that many falls can be prevented, rates of falls resulting in injury have not declined. METHODS: We conducted a pragmatic, cluster-randomized trial to evaluate the effectiveness of a multifactorial intervention that included risk assessment and individualized plans, administered by specially trained nurses, to prevent fall injuries. A total of 86 primary care practices across 10 health care systems were randomly assigned to the intervention or to enhanced usual care (the control) (43 practices each). The participants were community-dwelling adults, 70 years of age or older, who were at increased risk for fall injuries. The primary outcome, assessed in a time-to-event analysis, was the first serious fall injury, adjudicated with the use of participant report, electronic health records, and claims data. We hypothesized that the event rate would be lower by 20% in the intervention group than in the control group. RESULTS: The demographic and baseline characteristics of the participants were similar in the intervention group (2802 participants) and the control group (2649 participants); the mean age was 80 years, and 62.0% of the participants were women. The rate of a first adjudicated serious fall injury did not differ significantly between the groups, as assessed in a time-to-first-event analysis (events per 100 person-years of follow-up, 4.9 in the intervention group and 5.3 in the control group; hazard ratio, 0.92; 95% confidence interval [CI], 0.80 to 1.06; P = 0.25). The rate of a first participant-reported fall injury was 25.6 events per 100 person-years of follow-up in the intervention group and 28.6 events per 100 person-years of follow-up in the control group (hazard ratio, 0.90; 95% CI, 0.83 to 0.99; P = 0.004). The rates of hospitalization or death were similar in the two groups. CONCLUSIONS: A multifactorial intervention, administered by nurses, did not result in a significantly lower rate of a first adjudicated serious fall injury than enhanced usual care. (Funded by the Patient-Centered Outcomes Research Institute and others; STRIDE ClinicalTrials.gov number, NCT02475850.).
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Acidentes por Quedas/prevenção & controle , Lesões Acidentais/prevenção & controle , Administração dos Cuidados ao Paciente/métodos , Acidentes por Quedas/mortalidade , Acidentes por Quedas/estatística & dados numéricos , Lesões Acidentais/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Vida Independente , Masculino , Medicina de Precisão , Medição de Risco , Fatores de RiscoRESUMO
BACKGROUND: Elevated blood pressure after endovascular thrombectomy (EVT) has been associated with an increased risk of hemorrhagic transformation and poor functional outcomes. However, the optimal hemodynamic management after EVT remains unknown, and the blood pressure course in the acute phase of ischemic stroke has not been well characterized. This study aimed to identify patient subgroups with distinct blood pressure trajectories after EVT and study their association with radiographic and functional outcomes. METHODS: This multicenter retrospective cohort study included consecutive patients with anterior circulation large-vessel occlusion ischemic stroke who underwent EVT. Repeated time-stamped blood pressure data were recorded for the first 72 hours after thrombectomy. Latent variable mixture modeling was used to separate subjects into five groups with distinct postprocedural systolic blood pressure (SBP) trajectories. The primary outcome was functional status, measured on the modified Rankin Scale 90 days after stroke. Secondary outcomes included hemorrhagic transformation, symptomatic intracranial hemorrhage, and death. RESULTS: Two thousand two hundred sixty-eight patients (mean age [±SD] 69±15, mean National Institutes of Health Stroke Scale 15±7) were included in the analysis. Five distinct SBP trajectories were observed: low (18%), moderate (37%), moderate-to-high (20%), high-to-moderate (18%), and high (6%). SBP trajectory group was independently associated with functional outcome at 90 days (P<0.0001) after adjusting for potential confounders. Patients with high and high-to-moderate SBP trajectories had significantly greater odds of an unfavorable outcome (adjusted odds ratio, 3.5 [95% CI, 1.8-6.7], P=0.0003 and adjusted odds ratio, 2.2 [95% CI, 1.5-3.2], P<0.0001, respectively). Subjects in the high-to-moderate group had an increased risk of symptomatic intracranial hemorrhage (adjusted odds ratio, 1.82 [95% CI, 1-3.2]; P=0.04). No significant association was found between trajectory group and hemorrhagic transformation. CONCLUSIONS: Patients with acute ischemic stroke demonstrate distinct SBP trajectories during the first 72 hours after EVT that have differing associations with functional outcome. These findings may help identify potential candidates for future blood pressure modulation trials.
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Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea/fisiologia , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Procedimentos Endovasculares/efeitos adversos , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Acidente Vascular Cerebral/etiologia , Trombectomia/efeitos adversos , Resultado do TratamentoRESUMO
BACKGROUND: Multiple frailty screening tools are implemented; however, it is unclear whether they perform in a comparable way for both frailty detection and prediction of perioperative outcomes in patients undergoing lower-extremity revascularization. METHODS: Patients undergoing lower-extremity revascularization were identified from the Vascular Quality Initiative (VQI) national database. Two cohorts were established based on the revascularization type (percutaneous vascular interventions (PVI) or lower-extremity bypass). Frailty was assessed by the 5-item modified frailty index (mFI-5) and the VQI-derived risk analysis index (RAI). RESULTS: Out of 134,081 patients undergoing PVI, frailty was identified in 67% by mFI-5 and 28% by RAI. Similarly, out of 41,316 patients in the bypass cohort, frailty was identified in 69% by mFI-5 and 16% by RAI. There was little agreement between the two frailty tools for both vascular cohorts (PVI: kappa: 0.17; bypass: kappa: 0.13). In an adjusted analysis, frailty as assessed by mFI-5 and RAI was associated with higher odds of mortality in both cohorts (p < 0.001). A significant association between frailty and unplanned amputations was only noted in the bypass cohort when RAI was applied (OR: 1.50, p < 0.01). The addition of frailty to traditional PAD risk factors marginally improved model performance to predict mortality and unplanned major amputations. CONCLUSION: There was significant variation in frailty detection by mFI-5 and RAI. Although frailty was associated with mortality, the predictive value of these tools in predicting outcomes in PAD was limited. Future research should focus on designing new frailty screening tools specific to the PAD population.
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Fragilidade , Doença Arterial Periférica , Fragilidade/diagnóstico , Humanos , Extremidade Inferior/irrigação sanguínea , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/cirurgia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
Hand, foot, and mouth disease (HFMD) caused by enterovirus A71 (EV-A71) is a contagious viral disease, and toll-like receptors (TLRs) play essential roles in resisting the pathogen. The aim of this study was to assess the potential relationship between several TLRs polymorphisms and the HFMD severity in a Chinese children population. A total of 328 Chinese children with HFMD were included in the present study. The polymorphisms of TLR3 (rs3775290, rs3775291, rs3775296, rs1879026, rs5743312, rs5743313, rs5743303, rs13126816, and rs3775292), TLR4 (rs4986790, rs4986791, rs2149356, rs11536889, and rs41426344), TLR7 (rs179009, rs179010, rs179016, rs3853839, rs2302267, rs1634323, and rs5741880), and TLR8 (rs3764880, rs2159377, rs2407992, rs5744080, rs3747414, rs3764879, and rs5744069) genes were selected. The study indicated that individuals with the GG genotype of TLR3 single-nucleotide polymorphism rs1879026 had a higher risk of developing severe cases (GG vs. GT: OR = 1.875; 95% CI, 1.183-2.971; p = .007). Meanwhile, TLR3 rs3775290 CC genotype and C allele were associated with lower disease severity in females (CC vs. CT: OR = 0.350; 95% CI, 0.163-0.751; p = .006; C vs. T: OR = 0.566; 95% CI, 0.332-0.965; p = .036). TLR3 rs3775291 CC genotype showed 2.537 folds higher risk of developing severe cases in females (CC vs. CT: OR = 2.537; 95% CI, 1.108-5.806; p = .026). Moreover, TLR3 rs1879026 GG genotype was found to be related to increased risk of severe cases in males (GG vs. GT: OR = 2.076; 95% CI, 1.144-3.768; p = .016). The current findings show that the genetic variants of TLR3 rs1879026, rs3775290, and rs3775291 are associated with the severity of EV-A71-associated HFMD in a Chinese children population.
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Enterovirus Humano A , Predisposição Genética para Doença , Doença de Mão, Pé e Boca/genética , Polimorfismo de Nucleotídeo Único , Receptor 3 Toll-Like/genética , Alelos , Povo Asiático/genética , Estudos de Casos e Controles , Pré-Escolar , China , Feminino , Doença de Mão, Pé e Boca/patologia , Doença de Mão, Pé e Boca/virologia , Humanos , Lactente , Recém-Nascido , MasculinoRESUMO
BACKGROUND: Research suggests that growth in Black and Hispanic (minority) older adults' nursing home (NH) use may be the result of disparities in access to community-based and alternative long-term services and supports (LTSS). OBJECTIVE: We aimed to determine whether minority groups receiving care in NHs versus the community had fewer differences in their functional needs compared with the differences in nonminority older adults, suggesting a disparity. METHODS: We identified respondents aged 65 years or above with a diagnosis of Alzheimer disease or dementia in the 2016 Health and Retirement Study who reported requiring LTSS help. We performed unadjusted analyses to assess the difference in functional need between community and NH care. Functional need was operationalized using a functional limitations score and 6 individual activities of daily living. We compared the LTSS setting for minority older adults to White older adults using difference-in-differences. RESULTS: There were 186 minority older adults (community=75%, NH=25%) and 357 White older adults (community=50%, NH=50%). Between settings, minority older adults did not differ in education or marital status, but were younger and had greater income in the NH versus the community. The functional limitations score was higher in NHs than in the community for both groups. Functional needs for all 6 activities of daily living for the minority group were greater in NHs compared with the community. CONCLUSION: Functional need for minority older adults differed by setting while demographics varied in unexpected ways. Factors such as familial and financial support are important to consider when implementing programs to keep older adults out of NHs.
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Assistência de Longa Duração/estatística & dados numéricos , Grupos Minoritários/estatística & dados numéricos , Casas de Saúde/estatística & dados numéricos , Atividades Cotidianas , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer , Estudos Transversais , Demência , Demografia , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , População Branca/estatística & dados numéricosRESUMO
While the gold standard for clinical trials is to blind all parties-participants, researchers, and evaluators-to treatment assignment, this is not always a possibility. When some or all of the above individuals know the treatment assignment, this leaves the study open to the introduction of postrandomization biases. In the Strategies to Reduce Injuries and Develop Confidence in Elders (STRIDE) trial, we were presented with the potential for the unblinded clinicians administering the treatment, as well as the individuals enrolled in the study, to introduce ascertainment bias into some but not all events comprising the primary outcome. In this article, we present ways to estimate the ascertainment bias for a time-to-event outcome, and discuss its impact on the overall power of a trial vs changing of the outcome definition to a more stringent unbiased definition that restricts attention to measurements less subject to potentially differential assessment. We found that for the majority of situations, it is better to revise the definition to a more stringent definition, as was done in STRIDE, even though fewer events may be observed.
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Viés , Idoso , HumanosRESUMO
BACKGROUND/AIM: In clinical trials, there is potential for bias from unblinded observers that may influence ascertainment of outcomes. This issue arose in the Strategies to Reduce Injuries and Develop Confidence in Elders trial, a cluster randomized trial to test a multicomponent intervention versus enhanced usual care (control) to prevent serious fall injuries, originally defined as a fall injury leading to medical attention. An unblinded nurse falls care manager administered the intervention, while the usual care arm did not involve contact with a falls care manager. Thus, there was an opportunity for falls care managers to refer participants reporting falls to seek medical attention. Since this type of observer bias could not occur in the usual care arm, there was potential for additional falls to be reported in the intervention arm, leading to dilution of the intervention effect and a reduction in study power. We describe the clinical basis for ascertainment bias, the statistical approach used to assess it, and its effect on study power. METHODS: The prespecified interim monitoring plan included a decision algorithm for assessing ascertainment bias and adapting (revising) the primary outcome definition, if necessary. The original definition categorized serious fall injuries requiring medical attention into Type 1 (fracture other than thoracic/lumbar vertebral, joint dislocation, cut requiring closure) and Type 2 (head injury, sprain or strain, bruising or swelling, other). The revised definition, proposed by the monitoring plan, excluded Type 2 injuries that did not necessarily require an overnight hospitalization since these would be most subject to bias. These injuries were categorized into those with (Type 2b) and without (Type 2c) medical attention. The remaining Type 2a injuries required medical attention and an overnight hospitalization. We used the ratio of 2b/(2b + 2c) in intervention versus control as a measure of ascertainment bias; ratios > 1 indicated the likelihood of falls care manager bias. We determined the effect of ascertainment bias on study power for the revised (Types 1 and 2a) versus original definition (Types 1, 2a, and 2b). RESULTS: The estimate of ascertainment bias was 1.14 (95% confidence interval: 0.98, 1.30), providing evidence of the likelihood of falls care manager bias. We estimated that this bias diluted the hazard ratio from the hypothesized 0.80 to 0.86 and reduced power to under 80% for the original primary outcome definition. In contrast, adapting the revised definition maintained study power at nearly 90%. CONCLUSION: There was evidence of ascertainment bias in the Strategies to Reduce Injuries and Develop Confidence in Elders trial. The decision to adapt the primary outcome definition reduced the likelihood of this bias while preserving the intervention effect and study power.
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Acidentes por Quedas , Viés , Fraturas Ósseas , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidentes por Quedas/prevenção & controle , Idoso , Hospitalização , HumanosRESUMO
OBJECTIVE: To analyze and evaluate the nutritional composition of five main products of freshwater shrimp including crawfish, river prawn, macrobrachium, freshwater shrimp, exopalaemon modestus in Anhui Province. METHODS: Conventional and biochemical analytical method were used to detect the moisture, ash, crude protein, crude fat, amino acid, fatty acid, minerals and vitamin. RESULTS: The contents of crude protein, crude fat, ash of the five freshwater shrimp were 13. 9-20. 8 g/100 g edible, 0. 6-2. 2 g/100 g edible, 1. 5-4. 1 g/100 g edible, respectively. A total of 18 amino acids were detected, the content of which were 11600-18600 mg/100 g edible. The amount of nine essential amino acid was measured to be 5336-9342 mg/100 g edible. The main restrictive amino acids in the five kinds of shrimps were methionine and cysteine, threonine and valine. The essential amino acid indexes in five kinds of shrimps(EAAI) were 39. 62 and 31. 81, 28. 65, 44. 85, and 33. 48, respectively. Fourteen types of fatty acid were detected. The total content of fatty acid was 287-1851 mg/100 g edible. The monounsaturated fatty acid(MUFA) and the polyunsaturated fatty acid(PUFA) were 12-234 mg/100 g edible, 164-377 mg/100 g edible, respectively. Nine minerals were detected which including five microelements and four microelements. The content of calcium in river prawn, macrobrachium and exopalaemon modestus was higher than that in crawfish and freshwater shrimp. The content of phosphorus, kalium, sodium, magnesium in five freshwater shrimp were 221-296 mg/100 g edible, 196-278 mg/100 g edible, 120. 7-202. 7 mg/100 g edible, 37-95 mg/100 g edible, respectively. The content of iron, manganese, cuprum in crawfish were higher than the others. The content of zinc in river prawn and exopalaemon modestus was high. Moreover, the vitamin B_2 and E were also detected in five freshwater shrimp. The content of vitamin B_2 and E were 0. 02-0. 07 mg/100 g edible and 1. 61-3. 30 mg/100 g edible. CONCLUSION: Five main products of freshwater shrimp in Anhui belong to super nutritional value food which contained high protein, variety of amino acid, low fat, a certain amount of vitamin B_2 and E, rich in minerals.
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Ácidos Graxos , Alimentos Marinhos , Ácidos Graxos/análise , Água Doce , Minerais/análise , Valor Nutritivo , Alimentos Marinhos/análiseRESUMO
WRKY transcription factors are novel transcriptional regulatory factors, which play an important role in regulating plant development, metabolism and other physiological processes. In this study, a new Dendrobium officinale WRKY transcription factor, designated as DoWRKY1 was cloned by using RT-PCR and RACE (GenBank Accession No. KF953910). Bioinformatic analysis demonstrated that, the full-length cDNA of DoWRKY1 was 1,704 bp. And DoWRKY1 contained a 1,629 bp open reading frame (ORF) that encoding a peptide of 542 amino acid residues. The putative DoWRKY1 protein contained two conserved WRKY domains and it belonged to the group I WRKY family protein. Yeast one-hybrid experiment showed that DoWRKY1 had transcriptional activation ability in yeast, and it could activate the expression of downstream report genes (His3 and Ade2). Semi-quantitative RT-PCR experiment showed that DoWRKY1 expressed in roots, stems, leaves and protocorm-like bodies. Real-time qRT-PCR proved that DoWRKY1 could be induced by methyl jasmonate (MeJA) and chitosan (Chitosan), and the expression level of this gene can reach the expression peak at 2 h and 1 h, respectively. These results are useful for further determination of the regulation function of this gene in secondary metabolism of D. officinale.
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Dendrobium/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Clonagem Molecular , Regulação da Expressão Gênica de PlantasRESUMO
OBJECTIVE: Chronic graft-versus-host disease (cGVHD) is a significant complication following allogenic hematopoietic stem cell transplantation, often necessitating therapeutic interventions such as rituximab (RTX) and cyclosporin A (CsA). This study aims to elucidate the mechanisms by which RTX and CsA jointly address B-cell dysregulation in cGVHD, providing a theoretical foundation and scientific rationale for the treatment and prognostic evaluation of this condition. METHODS: A total of 30 cGVHD mouse models were established by subjecting recipient mice to total body irradiation followed by injection of a mixed suspension of bone marrow cells and splenocytes from donor mice. From Day 2 to Day 29 post-model establishment, the mice received subcutaneous administration of RTX and CsA. Throughout the study, body weight, clinical cGVHD scores, and survival rates were monitored. Blood samples were collected via the orbital venous plexus. Serum levels of B-cell activating factor (BAFF) and pro-inflammatory factors were measured using enzyme-linked immunosorbent assay (ELISA), and the ratio of regulatory B cells (Bregs) in the blood sample was assessed via flow cytometry. RESULTS: Mice with cGVHD exhibited a 14.5% decrease in body weight, elevated clinical scores, and more severe symptoms compared to the control group. Notably, all mice in both the cGVHD and control groups survived until the conclusion of the study. Induction of cGVHD resulted in B-cell dysregulation, evidenced by elevated serum BAFF levels and a decreased proportion of Bregs. However, treatment with RTX combined with CsA ameliorated B-cell dysregulation and significantly reduced serum levels of pro-inflammatory factors in cGVHD mice, with decreases of 39.78% in TNF-α and 37.89% in IL-6. CONCLUSION: The combination of RTX and CsA effectively mitigates B-cell dysregulation in cGVHD, thereby reducing the severity and progression of the disease.
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Amblyopia is the decreased best-corrected visual acuity (BCVA) in one or both eyes caused by the abnormal processing of visual input during development. One common cause of amblyopia is anisometropia, which has attracted widespread attention. Many structural changes occur in the primary and extrastriate visual areas of the cerebral cortex, as well as in the eyes, in patients with anisometropic amblyopia. Understanding these mechanisms has provided a favorable theoretical basis for treating anisometropic amblyopia. This article reviews the functional and anatomical changes and progress toward the treatment of anisometropic amblyopia.
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Ambliopia , Anisometropia , Humanos , Ambliopia/terapia , Acuidade Visual , Olho , Anisometropia/complicações , Anisometropia/terapiaRESUMO
In recent years, with the gradual maturation of myopia correction surgery, the changes in binocular visual function after surgery have attracted widespread attention. The accommodation of facility, the amplitude of accommodation, relative accommodation, and accommodation convergence/accommodation assembly are essential parameters for assessing binocular visual function. The changes in these parameters are significant for guiding patients in the design of the preoperative surgical approach and alleviating postoperative visual fatigue. This paper aims to guide the preoperative assessment, design, and postoperative visual training of refractive surgery in myopic patients from the perspective of changes in binocular visual function before and after myopia and surgery, which can improve accommodation and convergence function in patients after refractive surgery.
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Miopia , Procedimentos Cirúrgicos Refrativos , Humanos , Convergência Ocular , Miopia/cirurgia , Acomodação Ocular , Visão BinocularRESUMO
BACKGROUND AND OBJECTIVES: Marginal models with generalized estimating equations (GEE) are usually recommended for analyzing correlated ordinal outcomes which are commonly seen in a longitudinal study or clustered randomized trial (CRT). Within-cluster association is often of interest in longitudinal studies or CRTs, and can be estimated with paired estimating equations. However, the estimators for within-cluster association parameters and variances may be subject to finite-sample biases when the number of clusters is small. The objective of this article is to introduce a newly developed R package ORTH.Ord for analyzing correlated ordinal outcomes using GEE models with finite-sample bias corrections. METHODS: The R package ORTH.Ord implements a modified version of alternating logistic regressions with estimation based on orthogonalized residuals (ORTH), which use paired estimating equations to jointly estimate parameters in marginal mean and association models. The within-cluster association between ordinal responses is modeled by global pairwise odds ratios (POR). The R package also provides a finite-sample bias correction to POR parameter estimates based on matrix multiplicative adjusted orthogonalized residuals (MMORTH) for correcting estimating equations, and bias-corrected sandwich estimators with different options for covariance estimation. RESULTS: A simulation study shows that MMORTH provides less biased global POR estimates and coverage of their 95% confidence intervals closer to the nominal level than uncorrected ORTH. An analysis of patient-reported outcomes from an orthognathic surgery clinical trial illustrates features of ORTH.Ord. CONCLUSIONS: This article provides an overview of the ORTH method with bias-correction on both estimating equations and sandwich estimators for analyzing correlated ordinal data, describes the features of the ORTH.Ord R package, evaluates the performance of the package using a simulation study, and finally illustrates its application in an analysis of a clinical trial.
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Modelos Estatísticos , Humanos , Modelos Logísticos , Estudos Longitudinais , Análise por Conglomerados , Simulação por Computador , ViésRESUMO
Simulation studies play an important role in evaluating the performance of statistical models developed for analyzing complex survival data such as those with competing risks and clustering. This article aims to provide researchers with a basic understanding of competing risks data generation, techniques for inducing cluster-level correlation, and ways to combine them together in simulation studies, in the context of randomized clinical trials with a binary exposure or treatment. We review data generation with competing and semi-competing risks and three approaches of inducing cluster-level correlation for time-to-event data: the frailty model framework, the probability transform, and Moran's algorithm. Using exponentially distributed event times as an example, we discuss how to introduce cluster-level correlation into generating complex survival outcomes, and illustrate multiple ways of combining these methods to simulate clustered, competing and semi-competing risks data with pre-specified correlation values or degree of clustering.
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Modelos Estatísticos , Simulação por Computador , Probabilidade , Análise por ConglomeradosRESUMO
OBJECTIVES: In stepped-wedge cluster randomized trials (SW-CRTs), clusters are randomized not to treatment and control arms but to sequences dictating the times of crossing from control to intervention conditions. Randomization is an essential feature of this design but application of standard methods to promote and report on balance at baseline is not straightforward. We aimed to describe current methods of randomization and reporting of balance at baseline in SW-CRTs. STUDY DESIGN AND SETTING: We used electronic searches to identify primary reports of SW-CRTs published between 2016 and 2022. RESULTS: Across 160 identified trials, the median number of clusters randomized was 11 (Q1-Q3: 8-18). Sixty-three (39%) used restricted randomization-most often stratification based on a single cluster-level covariate; 12 (19%) of these adjusted for the covariate(s) in the primary analysis. Overall, 50 (31%) and 134 (84%) reported on balance at baseline on cluster- and individual-level characteristics, respectively. Balance on individual-level characteristics was most often reported by condition in cross-sectional designs and by sequence in cohort designs. Authors reported baseline imbalances in 72 (45%) trials. CONCLUSION: SW-CRTs often randomize a small number of clusters using unrestricted allocation. Investigators need guidance on appropriate methods of randomization and assessment and reporting of balance at baseline.
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Projetos de Pesquisa , Humanos , Distribuição Aleatória , Estudos Transversais , Análise por Conglomerados , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Microplastics (MPs) usually coexist with heavy metals (HMs) in soil. MPs can influence HMs mobility and bioavailability, but the underlying mechanisms remain largely unexplored. Here, polyethylene and polypropylene MPs were selected to investigate their effects and mechanisms of sorption-desorption, bioaccessibility and bioavailability of cadmium (Cd) in paddy soil. Batch experiments indicated that MPs significantly reduced the Cd sorption in soil (p < 0.05). Accordingly, soil with the MPs had lower boundary diffusion constant of Cd (C1= 0.847â¼1.020) and the Freundlich sorption constant (KF = 0.444-0.616) than that without the MPs (C1 = 0.894â¼1.035, KF = 0.500-0.655). X-ray diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy analyses suggested that the MPs reduced Cd chemisorption, by covering the soil active sites and thus blocking complexation of Cd with active oxygen sites and interrupting the formation of CdCO3 and Cd3P2 precipitates. Such effects of MPs enhanced about 1.2-1.5 times of Cd bioaccessibility and bioavailability in soil. Almost the same effects but different mechanisms of polyethylene and polypropylene MPs on Cd sorption in the soil indicated the complexity and pervasiveness of their effects. The findings provide new insights into impacts of MPs on the fate and risk of HMs in agricultural soil.