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  • 文章类型: Journal Article
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  • 文章类型: Journal Article
    Fezouata生物群(摩洛哥)是伯吉斯页岩型(BST)组合,提供了有关早期奥陶纪生态系统的大量信息。已经做了许多工作来将Fezouata生物群的保存与其他BST进行比较。然而,调查Fezouata生物群内保存变化的研究很少。这里,我们使用概率来研究Fezouataeumetazoans各种生态类别的保存。复杂的分食过程和特定于门的限制已导致在该生物群中更好地保存捕食者/清除剂。然而,在阴道和无柄分类群之间没有观察到保存差异。重要的是,Tremadocian类群比Floian类群保存得更好。因此,这项研究强调了摩洛哥Zagora地区BST保存窗口的逐渐关闭,并构成了未来Fezouata生物群的古生态和进化研究的基准。
    The Fezouata Biota (Morocco) is a Burgess Shale-type (BST) assemblage that provides a wealth of information on Early Ordovician ecosystems. Much work has been done to compare the preservation of the Fezouata Biota to other BSTs. However, studies investigating preservation variations within the Fezouata Biota are rare. Here, we use probabilities to investigate the preservation of various ecological categories of Fezouata eumetazoans. Complex taphonomic processes and phylum-specific constraints have led to the better preservation of predators/scavengers in this biota. However, no differences in preservation are observed between vagile and sessile taxa. Importantly, Tremadocian taxa are better preserved than Floian ones. As such, this study highlights the gradual closure of the BST window of preservation in the Zagora region of Morocco and constitutes a benchmark for future palaeoecological and evolutionary studies on the Fezouata Biota.
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  • 文章类型: Journal Article
    背景:ML预测模型已显示出其改善风险预测和辅助医疗决策的能力,然而,在哥伦比亚甚至南美,缺乏早期识别未来CKD快速进展者的准确性系统。
    目的:本研究的目的是开发一系列可解释的机器学习模型,以预测6个月时的GFR。9个月,和12个月。
    方法:超过29,000名CKD患者1至3b期(估计GFR,<60ml/min/1.73m2),平均3年随访数据。我们使用机器学习极限梯度提升(XGBoost)构建了三个模型来预测下一个eGFR。模型进行了内部和外部验证。此外,我们纳入了Shapley加法扩张(SHAP)值,以提供可解释的全球和局部预测模型。
    结果:所有模型在开发和外部验证中都表现出良好的性能。然而,6个月XGBoost预测模型在内部表现最好(MAE平均值=6.07;RSME=78.87),和外部验证(MAE平均值=6.45,RSME=18.94)。将预测的eGFR值推到较低值的前3个最有影响力的特征是eGFR和肌酐的内插值,和基线时的eGFR。
    结论:在当前研究中,我们开发并验证了机器学习模型,以预测不同间隔的下一个eGFR值。此外,我们试图通过提供透明的预测来解决预测解释的必要性。
    BACKGROUND: ML predictive models have shown their capability to improve risk prediction and assist medical decision-making, nevertheless, there is a lack of accuracy systems to early identify future rapid CKD progressors in Colombia and even in South America.
    OBJECTIVE: The purpose of this study was to develop a series of interpretable machine learning models that predict GFR at 6-months, 9-months, and 12-months.
    METHODS: Over 29,000 CKD patients stages 1 to 3b (estimated GFR, <60 ml/min / 1.73 m2) with an average of 3-year follow-up data were included. We used the machine learning extreme gradient boosting (XGBoost) to build three models to predict the next eGFR. Models were internally and externally validated. In addition, we included SHapley Additive exPlanation (SHAP) values to offer interpretable global and local prediction models.
    RESULTS: All models showed a good performance in development and external validation. However, the 6-months XGBoost prediction model showed the best performance in internal (MAE average= 6.07; RSME= 78.87), and in external validation (MAE average= 6.45, RSME= 18.94). The top 3 most influential features that pushed the predicted eGFR value to lower values were the interpolated values for eGFR and creatinine, and eGFR at baseline.
    CONCLUSIONS: In the current study we have developed and validated machine learning models to predict the next eGFR value at different intervals. Furthermore, we attempted to approach the need for prediction explanation by offering transparent predictions.
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  • 文章类型: Journal Article
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  • 文章类型: Journal Article
    由于种群成员之间的差异,大多数生物系统固有的变异性。在研究中通常观察到两种类型的变化:样本之间的差异和从样本估计总体参数(例如平均值)时的“误差”。虽然这些概念根本不同,相关的变化通常使用类似的符号表示-一个区间,表示具有下限和上限的值的范围。在本文中,我们将讨论如何使用常见的间隔(和误用)。
    Variability is inherent in most biological systems due to differences among members of the population. Two types of variation are commonly observed in studies: differences among samples and the \"error\" in estimating a population parameter (e.g. mean) from a sample. While these concepts are fundamentally very different, the associated variation is often expressed using similar notation-an interval that represents a range of values with a lower and upper bound. In this article we discuss how common intervals are used (and misused).
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  • 文章类型: Journal Article
    背景:在接受阶段性姑息治疗的功能单室心脏患者中,严重的房室瓣功能障碍可能与死亡率或需要移植有关。这项研究的目的是描述伴随房室瓣干预对单心室缓解的每个阶段的预后的影响,并确定与这些患者不良预后相关的风险因素。方法:从2013年到2022年,查询胸外科医师学会先天性心脏外科数据库中接受单心室姑息治疗的功能单心室心脏病患者。对与每个缓解阶段相对应的队列进行单独分析(1:初始缓解;2:上腔肺吻合术;3:Fontan程序)。人口统计学的双变量分析,诊断,合并症,术前危险因素,手术特征,并进行有或无房室瓣介入的结局.使用多元逻辑回归来确定与手术死亡率或主要发病率相关的预测因素。结果:伴随房室瓣介入与每个队列的手术死亡率或主要发病率风险增加相关(队列1:62%vs46%,P<.001;队列2:37%对19%,P<.001;队列3:22%对14%,P<.001)。队列1中的黑人种族(比值比[OR]3.151,95%CI1.181-9.649,P=.03)和队列2中的早产(OR1.776,95%CI1.049-3.005,P=.032)是发病率或死亡率下降的显着预测因素。结论:在单心室缓解的每个阶段,伴随的房室瓣介入是手术死亡率或主要发病率的危险因素。几个风险因素与这些结果相关,可能有助于指导决策。
    Background: Significant atrioventricular valve dysfunction can be associated with mortality or need for transplant in functionally univentricular heart patients undergoing staged palliation. The purposes of this study are to characterize the impact of concomitant atrioventricular valve intervention on outcomes at each stage of single ventricle palliation and to identify risk factors associated with poor outcomes in these patients. Methods: The Society of Thoracic Surgeons Congenital Heart Surgery Database was queried for functionally univentricular heart patients undergoing single ventricle palliation from 2013 through 2022. Separate analyses were performed on cohorts corresponding to each stage of palliation (1: initial palliation; 2: superior cavopulmonary anastomosis; 3: Fontan procedure). Bivariate analysis of demographics, diagnoses, comorbidities, preoperative risk factors, operative characteristics, and outcomes with and without concomitant atrioventricular valve intervention was performed. Multiple logistic regression was used to identify predictors associated with operative mortality or major morbidity. Results: Concomitant atrioventricular valve intervention was associated with an increased risk of operative mortality or major morbidity for each cohort (cohort 1: 62% vs 46%, P < .001; cohort 2: 37% vs 19%, P < .001; cohort 3: 22% vs 14%, P < .001). Black race in cohort 1 (odds ratio [OR] 3.151, 95% CI 1.181-9.649, P = .03) and preterm birth in cohort 2 (OR 1.776, 95% CI 1.049-3.005, P = .032) were notable predictors of worse morbidity or mortality. Conclusions: Concomitant atrioventricular valve intervention is a risk factor for operative mortality or major morbidity at each stage of single ventricle palliation. Several risk factors are associated with these outcomes and may be useful in guiding decision-making.
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  • 文章类型: Journal Article
    背景:世界儿科和先天性心脏手术数据库(WDPCHS),由世界儿童和先天性心脏病学会(WSPCHS)赞助,为成员计划提供复杂的先天性心脏手术结果分析。本报告是对WDPCHS活跃成员结果的七年描述性分析。
    方法:各个机构通过密码保护平台根据特定程序提交数据。收集数据,存储,并在KirklinSolutionsInc.进行了分析,总部设在伯明翰,阿拉巴马.本报告对2017年1月1日至2023年12月31日提交的这些程序进行了描述性分析。
    结果:总共提交了50,174例手术,总死亡率为4.6%。大多数提交的材料来自亚洲国家。这些国家提交的大多数病例属于统计死亡率第一类和第二类。室间隔缺损的修复(死亡率为0.8%)和法洛四联症的矫正(死亡率为2.0%)是提交给数据库的最常见程序。
    结论:WSPCHS在2017年完成了其使命之一,当时WDPCHS开始接受来自全球儿科和先天性心脏病手术项目的数据。在这样做的时候,它成为首批创建知识和经验交流平台的组织之一,无论特定计划或国家的社会经济地位如何。
    BACKGROUND: The World Database for Pediatric and Congenital Heart Surgery (WDPCHS), sponsored by the World Society for Pediatric and Congenital Heart Surgery (WSPCHS), provides complex congenital heart surgery outcomes analyses for member programs. This report represents the seven-year descriptive analysis of outcomes from active members of the WDPCHS.
    METHODS: Individual institutions submit data based on the specific procedure via a password protected platform. The data are collected, stored, and analyzed at Kirklin Solutions Inc., based in Birmingham, Alabama. This report presents a descriptive analysis of these procedures submitted from January 1, 2017, to December 31, 2023.
    RESULTS: A total of 50,174 procedures were submitted with an overall mortality of 4.6%. The majority of submissions were from Asian countries. The majority of cases submitted from these countries were of STAT mortality category I and II. Repair of a ventricular septal defect (with a mortality of 0.8%) and correction of tetralogy of Fallot (2.0% mortality) were the most common procedures submitted to the database.
    CONCLUSIONS: The WSPCHS accomplished one of its missions in 2017 when the WDPCHS began accepting data from pediatric and congenital heart surgery programs across the globe. In doing so, it became one of the first organizations to create a platform for the exchange of knowledge and experience, regardless of the socioeconomic status of the particular program or country.
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  • 文章类型: Journal Article
    生理学家通常将两次测量值的变化表示为初始值的比率。这通常是由以下假设引起的:绝对变化无法捕获在达到最终值过程中发生的变化的真实程度-如果单个案例之间存在初始变化。虽然以这种方式使用比率来标准化变化的幅度似乎是合理的,这样做的危险已经被广泛记录。比率经常具有棘手的统计特性,无论是孤立地采取还是使用回归等技术进行分析。一种计算标准化变化度量的新方法,基于主成分分析(PCA),被描述。它利用了初始集合内的共线性,绝对变化和最终值。当这些集合定义受PCA影响的变量时,作为第一主成分(PC1)上的绝对变化的负荷和PC1的特征值的乘积,获得变化的标准化度量。证明了从这些标准化度量的总体中抽取的样本:近似正态分布(与相应的比率不同);位于同一范围内;并保留比率的等级顺序。还表明,该方法可用于表示实验条件下相对于对照条件下获得的生理反应的幅度。关键点:比率的棘手统计特性和使用比率来标准化变化幅度的危险是众所周知的。一种计算标准化度量的新方法,基于主成分分析(PCA),被描述,它利用了初始集合内的共线性,绝对变化和最终值。从这些PCA衍生的度量的总体中提取的样本:近似正态分布(与相应的比率不同);与比率在相同的范围内;并保留比率的等级顺序。该方法还可以应用于表示在实验条件下相对于对照条件的生理反应的幅度。
    Physiologists often express the change in the value of a measurement made on two occasions as a ratio of the initial value. This is usually motivated by an assumption that the absolute change fails to capture the true extent of the alteration that has occurred in attaining the final value - if there is initial variation among individual cases. While it may appear reasonable to use ratios to standardize the magnitude of change in this way, the perils of doing so have been widely documented. Ratios frequently have intractable statistical properties, both when taken in isolation and when analysed using techniques such as regression. A new method of computing a standardized metric of change, based on principal components analysis (PCA), is described. It exploits the collinearity within sets of initial, absolute change and final values. When these sets define variables subjected to PCA, the standardized measure of change is obtained as the product of the loading of absolute change onto the first principal component (PC1) and the eigenvalue of PC1. It is demonstrated that a sample drawn from a population of these standardized measures: approximates a normal distribution (unlike the corresponding ratios); lies within the same range; and preserves the rank order of the ratios. It is also shown that this method can be used to express the magnitude of a physiological response in an experimental condition relative to that obtained in a control condition. KEY POINTS: The intractable statistical properties of ratios and the perils of using ratios to standardize the magnitude of change are well known. A new method of computing a standardized metric, based on principal components analysis (PCA), is described, which exploits the collinearity within sets of initial, absolute change and final values. A sample drawn from a population of these PCA-derived measures: approximates a normal distribution (unlike the corresponding ratios); lies within the same range as the ratios; and preserves the rank order of the ratios. The method can also be applied to express the magnitude of a physiological response in an experimental condition relative to a control condition.
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  • 文章类型: Journal Article
    临床实践中迫切需要预防血清肿的新干预措施。动物模型是测试这些干预措施的关键工具;然而,在临床和动物模型结果之间仍然存在显著的翻译差距.本系统综述旨在评估用于血清瘤预防的动物模型的方法学特征和质量。进行荟萃分析以估计对照组的预期血清肿发生率,并确定典型干预措施的效果大小。我们系统地检索了所有描述诱导血清肿形成的动物模型的研究。方法论特征,偏见的风险,并对研究质量进行评估。血清瘤体积和发病率数据用于荟萃分析。总的来说,包括55项研究,42人符合荟萃分析的条件。大鼠(69%)是最常用的物种,在这些模型中,乳房切除术(50%)是主要的外科手术。尽管所有研究都存在很大的偏见风险,观察到报告质量每十年有改善的趋势.荟萃分析显示,典型对照组的平均血清瘤发生率为90%。平均干预措施使血清肿发生率减半(RR=0.49;CI0.35,0.70),血清肿体积显着减少(SMD=-3.31;CI-4.21,-2.41),尽管存在明显的异质性。总之,用于血清肿预防的动物模型表现出方法学缺陷和多种偏倚风险。实施足够有效的阳性和阴性对照组可以提高这些模型的内部有效性。需要更多的研究来进一步开发动物血清瘤模型。
    Novel interventions for seroma prevention are urgently needed in clinical practice. Animal models are pivotal tools for testing these interventions; however, a significant translational gap persists between clinical and animal model outcomes. This systematic review aims to assess the methodological characteristics and quality of animal models utilized for seroma prevention. A meta-analysis was performed to estimate the expected seroma incidence rate for control groups and determine the effect size of typical interventions. We systematically retrieved all studies describing animal models in which seroma formation was induced. Methodological characteristics, risks of bias, and study quality were assessed. Seroma volume and -incidence data were used for the meta-analysis. In total, 55 studies were included, with 42 eligible for meta-analysis. Rats (69%) were the most frequently used species, with mastectomy (50%) being the predominant surgical procedure in these models. Despite significant risks of bias across all studies, an improving trend in reporting quality per decade was observed. The meta-analysis revealed an average seroma incidence of 90% in typical control groups. The average intervention halved the seroma incidence (RR = 0.49; CI 0.35, 0.70) and significantly reduced seroma volume (SMD = -3.31; CI -4.21, -2.41), although notable heterogeneity was present. In conclusion, animal models for seroma prevention exhibit methodological flaws and multiple risks of bias. Implementing sufficiently powered positive and negative control groups could improve the internal validity of these models. More research is needed for further development of animal seroma models.
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  • 文章类型: Journal Article
    背景:有人担心与哌醋甲酯(MTH)使用相关的潜在心血管(CV)不良反应。然而,关于MTH长期安全性的证据有限.
    目的:评估使用MTH是否与长期CV风险相关。
    方法:这是一项回顾性队列研究,使用台湾健康与福利数据库2003-2017年的数据。包括新诊断为注意力缺陷和多动障碍(ADHD)且年龄在3至18岁之间的患者。评估两种治疗状态:初始治疗≥7天和≥180天。将接受MTH治疗的患者与接受非药物治疗的患者进行比较。使用一对一倾向评分匹配来平衡组间差异。研究结果包括重大CV事件,慢性CV疾病,心源性休克和全因死亡率。Cox比例风险模型用于估计两组之间的HR。
    结果:我们从307459例ADHD患者开始。排除后,224732名患者被纳入最终队列。结果显示,与非多动症药物使用者相比,接受MTH治疗超过7天的患者发生主要CV事件的风险相似(HR0.85,95%CI0.72~0.99;p=0.040).在治疗超过180天的组中发现了相同的趋势(HR0.83,95%CI0.69至1.00;p=0.050)。敏感性分析的结果与所有组和个体结局的主要分析一致。
    结论:短期使用MTH并没有增加ADHD患者的CV风险。关于长期使用MTH和心源性休克和死亡风险的更多证据是必要的。
    BACKGROUND: There have been concerns about the potential cardiovascular (CV) adverse effects associated with methylphenidate (MTH) use. However, only limited evidence exists on the long-term safety of MTH.
    OBJECTIVE: To evaluate whether MTH use is associated with long-term CV risk.
    METHODS: This was a retrospective cohort study using 2003-2017 data from the Health and Welfare Database in Taiwan. Patients newly diagnosed with attention deficit and hyperactivity disorder (ADHD) and between 3 and 18 years of age were included. Two treatment statuses were assessed: initial treatment ≥7 days and ≥180 days. Patients treated with MTH were compared with those receiving non-medication therapy. One-to-one propensity score matching was used to balance between-group differences. Study outcomes included major CV events, chronic CV disease, cardiogenic shock and all-cause mortality. Cox proportional hazard models were used to estimate HRs between the two groups.
    RESULTS: We began with 307 459 patients with ADHD. After exclusion, 224 732 patients were included in the final cohort. The results showed that compared with non-ADHD medication users, patients who were treated with MTH for more than 7 days had a similar risk of major CV events (HR 0.85, 95% CI 0.72 to 0.99; p=0.040). Identical trends were found in groups who were treated for more than 180 days (HR 0.83, 95% CI 0.69 to 1.00; p=0.050). The results of the sensitivity analyses were consistent with the main analyses across all groups and individual outcomes.
    CONCLUSIONS: Short-term MTH use did not increase CV risk among patients with ADHD. More evidence on long-term MTH use and risk of cardiogenic shock and death is warranted.
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