Biological Variation, Population

生物变异,人口
  • 文章类型: Journal Article
    背景:多位点致病性变异(MPV)是影响基因组多个基因位点或区域的遗传变化,共同导致多个分子诊断。MPV也可能导致一个核心家族内受影响的个体之间的家族内表型变异。在这项研究中,我们旨在进一步了解MPV对个别研究对象疾病表现的影响,并探索家族背景下人类基因组的复杂性。
    方法:我们对先前诊断为各种神经发育障碍(NDD)的47对同胞的外显子组测序数据和纯合性(ROH)区域运行进行了系统的重新分析。
    结果:我们在8.5%的家庭中发现具有由长ROH区域驱动的MPV的兄弟姐妹(4/47)。MPV患者表现出明显更高的FROH值(p值=1.4e-2)和更大的总ROH长度(p值=1.8e-2)。长ROH区域主要促成这种模式;具有MPV的兄弟姐妹的长ROH区域总大小大于所有家庭的兄弟姐妹(p值=6.9e-3)。然而,与具有单基因座致病变体的兄弟姐妹相比,具有MPV的兄弟姐妹中的短ROH区域的总大小较低(p值=0.029),并且同胞对之间的中等ROH区域没有统计学上的显着差异(p值=0.52)。
    结论:这项研究揭示了在有受影响的兄弟姐妹对的家庭中考虑MPV的重要性,以及ROH作为解释家庭内临床变异性的辅助工具的作用。识别携带MPV的个体可能对疾病管理有影响,识别不同家庭成员可能的疾病风险,遗传咨询和探索个性化治疗方法。
    BACKGROUND: Multilocus pathogenic variants (MPVs) are genetic changes that affect multiple gene loci or regions of the genome, collectively leading to multiple molecular diagnoses. MPVs may also contribute to intrafamilial phenotypic variability between affected individuals within a nuclear family. In this study, we aim to gain further insights into the influence of MPVs on a disease manifestation in individual research subjects and explore the complexities of the human genome within a familial context.
    METHODS: We conducted a systematic reanalysis of exome sequencing data and runs of homozygosity (ROH) regions of 47 sibling pairs previously diagnosed with various neurodevelopmental disorders (NDD).
    RESULTS: We found siblings with MPVs driven by long ROH regions in 8.5% of families (4/47). The patients with MPVs exhibited significantly higher FROH values (p-value = 1.4e-2) and larger total ROH length (p-value = 1.8e-2). Long ROH regions mainly contribute to this pattern; the siblings with MPVs have a larger total size of long ROH regions than their siblings in all families (p-value = 6.9e-3). Whereas the short ROH regions in the siblings with MPVs are lower in total size compared to their sibling pairs with single locus pathogenic variants (p-value = 0.029), and there are no statistically significant differences in medium ROH regions between sibling pairs (p-value = 0.52).
    CONCLUSIONS: This study sheds light on the significance of considering MPVs in families with affected sibling pairs and the role of ROH as an adjuvant tool in explaining clinical variability within families. Identifying individuals carrying MPVs may have implications for disease management, identification of possible disease risks to different family members, genetic counseling and exploring personalized treatment approaches.
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  • 文章类型: Journal Article
    背景:贝克尔肌营养不良症(BMD)是一种由于肌营养不良蛋白基因(DMD)中的框内突变而导致的肌营养不良蛋白病,其决定了肌营养不良蛋白在肌肉水平的减少。BMD具有广泛的临床变异性,具有不同程度的残疾。鉴于即将进行的临床试验,还需要进行自然史研究。
    目标:从最初的32名BMD成年受试者的队列中,我们介绍了28例患者的详细表型特征,然后提供他们的临床自然史在12个月的过程中的18和24个月的13。
    方法:对每位患者进行基因鉴定。基线,1年和2年评估包括北极星门诊评估(NSAA),定时功能测试(爬升和下降四个楼梯的时间),6分钟步行测试(6MWT),Walton和Gardner-Medwin量表和医学研究委员会(MRC)量表。24个月后,在基线和9例患者的亚组中获得了肌肉磁共振成像(MRI)。心脏功能数据(心电图,超声心动图,和心脏MRI)也被收集。
    结论:在临床异质性中,在45-Xdel患者中经常观察到更严重的受累,疾病进展超过两年。6MWT在随访期间似乎对检测来自基线的改变敏感,而通过MRC测试没有观察到变化。下肢肌肉MRI与临床参数相关。我们的研究进一步强调了BMD成年患者的表型变异性如何难以描述统一的病程,并证实了确定预测参数和生物标志物以对患者进行分层的必要性。
    UNASSIGNED: Becker muscular dystrophy (BMD) is a dystrophinopathy due to in-frame mutations in the dystrophin gene (DMD) which determines a reduction of dystrophin at muscle level. BMD has a wide spectrum of clinical variability with different degrees of disability. Studies of natural history are needed also in view of up-coming clinical trials.
    UNASSIGNED: From an initial cohort of 32 BMD adult subjects, we present a detailed phenotypic characterization of 28 patients, then providing a description of their clinical natural history over the course of 12 months for 18 and 24 months for 13 of them.
    UNASSIGNED: Each patient has been genetically characterized. Baseline, and 1-year and 2 years assessments included North Star Ambulatory Assessment (NSAA), timed function tests (time to climb and descend four stairs), 6-minute walk test (6MWT), Walton and Gardner-Medwin Scale and Medical Research Council (MRC) scale. Muscle magnetic resonance imaging (MRI) was acquired at baseline and in a subgroup of 9 patients after 24 months. Data on cardiac function (electrocardiogram, echocardiogram, and cardiac MRI) were also collected.
    UNASSIGNED: Among the clinical heterogeneity, a more severe involvement is often observed in patients with 45-X del, with a disease progression over two years. The 6MWT appears sensitive to detect modification from baseline during follow up while no variation was observed by MRC testing. Muscle MRI of the lower limbs correlates with clinical parameters.Our study further highlights how the phenotypic variability of BMD adult patients makes it difficult to describe an uniform course and substantiates the need to identify predictive parameters and biomarkers to stratify patients.
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  • 文章类型: Journal Article
    加性遗传变异,VA,是预测适应性和中性表型进化的关键参数。人口统计学的变化(例如近亲繁殖增加)可以改变VA,但它们如何做到这一点取决于(通常未知的)基因作用和许多基因座的等位基因频率。例如,当等位基因效应是加性的时,VA与近交系数成比例地增加,但是,当等位基因频率在具有优势效应的因果基因座上不相等时,可能会发生更小(或更大)的增加。这里,我们描述了一种实验方法来评估近亲繁殖下优势效应缩小VA的潜力。在果蝇中应用强大的配对谱系设计,我们测量了通过随机或兄弟姐妹交配繁殖的半兄弟姐妹家庭的11个翅膀性状,仅纯合性不同(不是等位基因频率)。尽管近亲繁殖和检测小VA的巨大能力,我们检测到近交对遗传(共)方差的预期累加效应没有偏差。我们的结果表明,相对于加性效应,平均优势系数非常小,或者等位基因频率在影响翅膀性状的基因座上相对相等。我们概述了这种配对谱系方法的进一步机会,以揭示VA的特征,提供对历史选择和未来进化潜力的洞察。
    Additive genetic variance, VA, is the key parameter for predicting adaptive and neutral phenotypic evolution. Changes in demography (e.g. increased close-relative inbreeding) can alter VA, but how they do so depends on the (typically unknown) gene action and allele frequencies across many loci. For example, VA increases proportionally with the inbreeding coefficient when allelic effects are additive, but smaller (or larger) increases can occur when allele frequencies are unequal at causal loci with dominance effects. Here, we describe an experimental approach to assess the potential for dominance effects to deflate VA under inbreeding. Applying a powerful paired pedigree design in Drosophila serrata, we measured 11 wing traits on half-sibling families bred via either random or sibling mating, differing only in homozygosity (not allele frequency). Despite close inbreeding and substantial power to detect small VA, we detected no deviation from the expected additive effect of inbreeding on genetic (co)variances. Our results suggest the average dominance coefficient is very small relative to the additive effect, or that allele frequencies are relatively equal at loci affecting wing traits. We outline the further opportunities for this paired pedigree approach to reveal the characteristics of VA, providing insight into historical selection and future evolutionary potential.
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  • 文章类型: Journal Article
    背景:鉴于噬菌体附着受体的特异性,目前使用单一的细菌分离来匹配噬菌体治疗剂,从而将活性外推到体内所有细菌。始终如一,金黄色葡萄球菌的主要噬菌体附着受体是磷壁酸,并且已知该受体在不同的体内环境中具有表型变异。因此,本研究的目的是确定噬菌体活性在所有体内假体关节感染环境中是否相似。
    方法:用56个噬菌体库分析了3例人工关节感染患者的生长抑制,这些患者的金黄色葡萄球菌来自关节穿刺培养物和至少3个深层组织培养物。
    结果:在不同的体内环境中观察到不一致的噬菌体活性。此外,对关节穿刺术分离株具有最强大的裂解潜力的噬菌体通常没有表现出与所有深层组织临床分离株相对应的活性。
    结论:不同的体内临床环境之间可能会发生噬菌体活性的变化,这可能是对磷壁酸不同糖基化模式的继发。因此,如果存在不一致的活动,用具有活性的噬菌体撤退可能是有效的,可重复的结果。
    BACKGROUND: Given the specificity of bacteriophage attachment receptors, a single bacterial isolate is currently utilized to match to a bacteriophage therapeutic, thereby extrapolating activity to all bacteria in vivo. Consistently, the main bacteriophage attachment receptor for Staphylococcus aureus is teichoic acid, and it is known that this receptor has phenotypic variations in different in vivo environments. Consequently, the aim of this study was to determine whether bacteriophage activity is similar across all in vivo prosthetic joint infection environments.
    METHODS: Three patients with prosthetic joint infections who had S. aureus grow from arthrocentesis cultures and at least three deep tissue cultures were analyzed for growth inhibition with a library of 56 bacteriophages.
    RESULTS: Discordant bacteriophage activity was seen across the different in vivo environments. Furthermore, bacteriophages with the most robust lytic potential to the arthrocentesis isolates usually did not demonstrate activity corresponding to all the deep tissue clinical isolates.
    CONCLUSIONS: Variations of bacteriophage activity can occur between the different in vivo clinical environments, which is likely secondary to different glycosylation patterns of teichoic acid. Consequently, if discordant activity is present, retreating with bacteriophages that have activity is likely needed for effective, reproducible outcomes.
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  • 文章类型: Journal Article
    背景房颤(AF)患者经常使用阿哌沙班2.5mg每日两次(BID)治疗,可能是为了降低出血风险。然而,这种方法有可能增加缺血性卒中的风险.如果一次测量可以可靠地识别药物水平高的患者,增加的卒中风险可以通过将标签外剂量减少限制在此类患者来缓解.目的本研究旨在确定在2个月内重复测试时,单一的高阿哌沙班水平是否可以预测类似的高水平。方法在这项前瞻性队列研究中,临床患者接受阿哌沙班5mgBID治疗房颤或静脉血栓栓塞症,在基线和2个月时使用STA-Liquid抗Xa测定法测量阿哌沙班的峰和谷水平。我们计算了水平保持在上五分之一的患者比例。结果在100名患者中,82人第二次来了,其中55人接受阿哌沙班5mgBID治疗。七(63.6%,95%置信区间[CI]:35.4-84.8%)和9(81.8%,95%CI:52.3-94.9%),11例患者的基线波谷和峰值水平在上五分之一,分别,有一个随后的水平保持在这个范围内。只有一个(9.1%,95%CI:1.6-37.7%)患者的后续水平略低于中位数。结论阿哌沙班的波谷和峰值水平在单次出现高水平的患者中,在2个月内重复测定时通常保持较高。因此,在被认为有高出血风险的患者中发现高阿哌沙班水平,允许医师考虑超说明书使用2.5mgBID剂量,以限制其用于不太可能暴露于血栓形成风险增加的选定患者.
    Background  Patients with atrial fibrillation (AF) are frequently treated with apixaban 2.5-mg twice daily (BID) off-label, presumably to reduce the bleeding risk. However, this approach has the potential to increase the risk of ischemic stroke. If a single measurement could reliably identify patients with high drug levels, the increased stroke risk may be mitigated by confining off-label dose reduction to such patients. Objectives  This study aimed to determine whether a single high apixaban level is predictive of a similarly high level when the test is repeated in 2 months. Methods  In this prospective cohort study of clinic patients receiving apixaban 5-mg BID for AF or venous thromboembolism, peak and trough apixaban levels were measured using the STA-Liquid anti-Xa assay at baseline and 2 months. We calculated the proportions of patients with levels that remained in the upper quintile. Results  Of 100 enrolled patients, 82 came for a second visit, 55 of whom were treated with apixaban 5-mg BID. Seven (63.6%, 95% confidence interval [CI]: 35.4-84.8%) and nine (81.8%, 95% CI: 52.3-94.9%) of 11 patients with a baseline trough and peak level in the upper quintile, respectively, had a subsequent level that remained within this range. Only one (9.1%, 95% CI: 1.6-37.7%) patient had a subsequent level that fell just lower than the median. Conclusion  The trough and peak levels of apixaban in patients who have a high level on a single occasion, usually remain high when the assay is repeated in 2 months. Accordingly, the finding of a high apixaban level in patients deemed to be at high risk of bleeding, allows physicians contemplating off-label use of the 2.5-mg BID dose to limit its use to selected patients who are less likely to be exposed to an increased risk of thrombosis.
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  • 文章类型: Journal Article
    在大流行的最初几个月,与COVID-19相关的限制会影响体重和体重相关因素。然而,纵向分析很少。一个在线,纵向研究是在自我选择的英国成年人中进行的(n=1818),涉及三项调查(5月至6月,8月-9月,2020年11月-12月),涵盖人体测量学,社会人口统计学,COVID-19相关和行为测量。使用广义估计方程对数据进行分析。自我报告的平均体重/体重指数(BMI)在5月至6月期间和8月至9月期间显着增加(分别为74.95至75.33kg/26.22kg/m2至26.36kg/m2,p<0.001),然后显著下降至11-12月(至75.06kg/26.27kg/m2,p<0.01),与5-6月水平相当(p=0.274/0.204)。然而,有很大的个体差异,37.0%/26.7%增加(平均3.64kg(95%置信区间:3.32,3.97)/1.64kg/m2(1.49,1.79)),在5-6月和11-12月之间,体重/BMI下降了34.5%/26.3%(平均3.59kg(3.34,3.85)/1.53kg/m2(1.42,1.63))。体重/BMI增加与初始BMI呈显著负相关,与每月高脂肪呈正相关,盐和糖(HFSS)零食摄入量和饮酒,仅对于BMI,年龄较大。协会是时变的;较低的初始BMI,在8-9月和11-12月期间,较高的HFSS零食摄入量和高风险饮酒与保持体重/BMI增加相关.英国成年人的平均体重/BMI在2020年5月至6月和11月至12月之间波动。然而,体重/BMI轨迹的巨大个体差异表明大流行对健康的长期影响,与食物和酒精消费有关。
    COVID-19-related restrictions impacted weight and weight-related factors during the initial months of the pandemic. However, longitudinal analyses are scarce. An online, longitudinal study was conducted among self-selected UK adults (n = 1818), involving three surveys (May-June, August-September, November-December 2020), covering anthropometric, sociodemographic, COVID-19-related and behavioural measures. Data were analysed using generalised estimating equations. Self-reported average weight/body mass index (BMI) significantly increased between the May-June period and the August-September period (74.95 to 75.33 kg/26.22 kg/m2 to 26.36kg/m2, p < 0.001, respectively), and then significantly decreased to November-December (to 75.06 kg/26.27 kg/m2, p < 0.01), comparable to May-June levels (p = 0.274/0.204). However, there was great interindividual variation, 37.0%/26.7% increased (average 3.64 kg (95% confidence interval: 3.32, 3.97)/1.64 kg/m2 (1.49, 1.79)), and 34.5%/26.3% decreased (average 3.59 kg (3.34, 3.85)/1.53 kg/m2 (1.42, 1.63)) weight/BMI between May-June and November-December. Weight/BMI increase was significantly negatively associated with initial BMI, and positively associated with monthly high fat, salt and sugar (HFSS) snacks intake and alcohol consumption, and for BMI only, older age. Associations were time-varying; lower initial BMI, higher HFSS snacks intake and high-risk alcohol consumption were associated with maintaining weight/BMI increases between August-September and November-December. The average weight/BMI of UK adults fluctuated between May-June and November-December 2020. However, the substantial interindividual variation in weight/BMI trajectories indicates long-term health impacts from the pandemic, associated with food and alcohol consumption.
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  • 文章类型: Journal Article
    帕金森病在症状表现和进展方面具有异质性。增加对这两个方面的了解可以更好地管理患者并改善临床试验设计。以前的帕金森病进展建模方法假设亚组内的静态进展轨迹,并没有充分说明复杂的药物效应。我们的目标是建立帕金森病的统计进展模型,该模型可解释个体内和个体间的变异性和药物作用。
    在这项纵向数据研究中,我们从帕金森病进展标志物倡议(PPMI)纵向观察研究中收集了423例早期帕金森病患者和196例健康对照者长达7年的数据.应用对比潜在变量模型,然后应用新颖的个性化输入输出隐马尔可夫模型来定义疾病状态。使用统计测试对七个关键的运动或认知结果(轻度认知障碍,痴呆症,运动障碍,电机波动的存在,运动波动导致的功能障碍,Hoehn和Yahr得分,和死亡)在学习阶段不使用。结果在来自美国国家神经系统疾病和中风研究所帕金森病生物标志物计划(PDBP)的610名帕金森病患者的独立样本中得到验证。
    PPMI数据于2018年7月25日下载,药物信息于2018年9月24日下载,PDBP数据于2020年6月15日至6月24日下载。该模型发现了八种疾病状态,主要通过功能损害来区分,震颤,运动迟缓,和神经精神病学措施。状态8,终端状态,关键临床结局的患病率最高,包括19例记录的痴呆病例中的18例(95%).在研究开始时,333名患者中有4名(1%)处于状态8,333名患者中有138名(41%)在第5年达到第8阶段。然而,起始状态的排名与5年内达到状态8的排名不匹配。总的来说,从状态5开始的患者至终末期的时间最短(中位数2·75[95%CI1·75-4·25]年).
    我们开发了早期帕金森病的统计进展模型,该模型考虑了个体内和个体间的变异性和药物作用。我们的预测模型发现了非连续的,重叠的疾病进展轨迹,支持使用非确定性疾病进展模型,并提示静态亚型分配在捕获帕金森病进展的全谱时可能无效。
    迈克尔·J·福克斯基金会。
    Parkinson\'s disease is heterogeneous in symptom presentation and progression. Increased understanding of both aspects can enable better patient management and improve clinical trial design. Previous approaches to modelling Parkinson\'s disease progression assumed static progression trajectories within subgroups and have not adequately accounted for complex medication effects. Our objective was to develop a statistical progression model of Parkinson\'s disease that accounts for intra-individual and inter-individual variability and medication effects.
    In this longitudinal data study, data were collected for up to 7-years on 423 patients with early Parkinson\'s disease and 196 healthy controls from the Parkinson\'s Progression Markers Initiative (PPMI) longitudinal observational study. A contrastive latent variable model was applied followed by a novel personalised input-output hidden Markov model to define disease states. Clinical significance of the states was assessed using statistical tests on seven key motor or cognitive outcomes (mild cognitive impairment, dementia, dyskinesia, presence of motor fluctuations, functional impairment from motor fluctuations, Hoehn and Yahr score, and death) not used in the learning phase. The results were validated in an independent sample of 610 patients with Parkinson\'s disease from the National Institute of Neurological Disorders and Stroke Parkinson\'s Disease Biomarker Program (PDBP).
    PPMI data were download July 25, 2018, medication information was downloaded on Sept 24, 2018, and PDBP data were downloaded between June 15 and June 24, 2020. The model discovered eight disease states, which are primarily differentiated by functional impairment, tremor, bradykinesia, and neuropsychiatric measures. State 8, the terminal state, had the highest prevalence of key clinical outcomes including 18 (95%) of 19 recorded instances of dementia. At study outset 4 (1%) of 333 patients were in state 8 and 138 (41%) of 333 patients reached stage 8 by year 5. However, the ranking of the starting state did not match the ranking of reaching state 8 within 5 years. Overall, patients starting in state 5 had the shortest time to terminal state (median 2·75 [95% CI 1·75-4·25] years).
    We developed a statistical progression model of early Parkinson\'s disease that accounts for intra-individual and inter-individual variability and medication effects. Our predictive model discovered non-sequential, overlapping disease progression trajectories, supporting the use of non-deterministic disease progression models, and suggesting static subtype assignment might be ineffective at capturing the full spectrum of Parkinson\'s disease progression.
    Michael J Fox Foundation.
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  • 文章类型: Journal Article
    The combination of substance use and psychiatric disorders is one of the most common comorbidities. The objective of this study was to perform a genome-wide association study of this comorbidity (Com), substance use alone (Subs), and psychiatric symptomatology alone (Psych) in the Mexican population. The study included 3914 individuals of Mexican descent. Genotyping was carried out using the PsychArray microarray and genome-wide correlations were calculated. Genome-wide associations were analyzed using multiple logistic models, polygenic risk scores (PRSs) were evaluated using multinomial models, and vertical pleiotropy was evaluated by generalized summary-data-based Mendelian randomization. Brain DNA methylation quantitative loci (brain meQTL) were also evaluated in the prefrontal cortex. Genome-wide correlation and vertical pleiotropy were found between all traits. No genome-wide association signals were found, but 64 single-nucleotide polymorphism (SNPs) reached nominal associations (p < 5.00e-05). The SNPs associated with each trait were independent, and the individuals with high PRSs had a higher prevalence of tobacco and alcohol use. In the multinomial models all of the PRSs (Subs-PRS, Com-PRS, and Psych-PRS) were associated with all of the traits. Brain meQTL of the Subs-associated SNPs had an effect on the genes enriched in insulin signaling pathway, and that of the Psych-associated SNPs had an effect on the Fc gamma receptor phagocytosis pathway.
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  • 文章类型: Journal Article
    背景:这项研究的主要目的是发现酶促抗氧化剂的活性与小黑麦植物的谷物产量之间可能的结构关联,以及确定可能对这种关联有效的基因型变异性。因此,超氧化物歧化酶(SOD)同工酶(Mn-SOD,Cu/Zn-SOD,和Fe-SOD)进行了评估,以区分SOD表达与小黑麦抗旱性之间的任何可能关系。提出了一种基于测量特征区分优秀基因型的新分析方法。此外,引入了一种基于SAS语言(IML)的新编程方法来估计基于组合ANOVA模型(线性混合模型)的遗传参数,它能够用于除当前研究之外的任何领域研究。
    方法:在正常和干旱胁迫条件下,在6年(三个不同位置)研究了30种小黑麦基因型。因此,根据遗传变异的结果,热图分析,双plot图,和聚类技术,选择遗传距离最大的两个基因型,评价三种SOD同工酶在芽和根器官中的差异表达谱。
    结果:田间试验和生物信息学结果表明,超氧化物歧化酶(SOD)是小黑麦对干旱胁迫抗性影响最大的抗氧化剂;它可以在早期阶段用作间接选择指数,以区分对干旱胁迫的抗性基因型。此外,在干旱胁迫下,两种基因型的Mn-SOD和Fe-SOD表达水平大致相同。然而,耐性基因型根和芽中Cu/Zn-SOD表达水平高于易感基因型。
    结论:热图分析首次用于筛选合适的基因型,显示出高度能够区分精英基因型并指出选择标准的适当特征。生物信息学结果表明,SOD比其他酶促抗氧化剂更重要,被认为是转基因目的的选择标准或候选基因。根据表达结果,Mn-SOD被宣布为一般同工酶,可能在大多数物种中高度表达,while,引入Cu/Zn-SOD作为基因型特异性同工酶,可能在耐受基因型中表达更多。
    BACKGROUND: The main objectives of this study were to find the possible structural association between the activity of enzymatic antioxidants and the grain yield of triticale plants as well as identifying the genotypic variability which might be effective on this association. Accordingly, expression levels of superoxide dismutase (SOD) isozymes (Mn-SOD, Cu/Zn-SOD, and Fe-SOD) were appraised to distinguish any possible relationship between SOD expression and drought resistance of triticale. A novel analytical method for distinguishing elite genotypes based on measured features was proposed. Additionally, a new programing based on SAS-language (IML) was introduced to estimate the genetic parameters rooted from combined ANOVA model (linear mixed model), which is capable of being used in any field study other than the current one.
    METHODS: Thirty genotypes of triticale were studied under normal and drought stress conditions during 6 years (three different locations). Accordingly, based on the results of genetic variability, heatmap analysis, biplot graph, and clustering technique, two genotypes with the highest genetic distance were selected to appraise the differential expression profiling of three SOD isozyme in shoot and root organs.
    RESULTS: Field experiments and bioinformatics results showed that superoxide dismutase (SOD) was the most influential antioxidant in resistance of triticale to drought stress; therefore, it could be used as an indirect selection index in early stages to distinguish resistant genotypes to drought stress. Additionally, Mn-SOD and Fe-SOD showed roughly similar expression levels for both genotypes under drought stress. However, Cu/Zn-SOD expression level was higher in root and shoot of the tolerant genotype than the susceptible genotype.
    CONCLUSIONS: Heatmap analysis that is applied for the first time to screen suitable genotypes, showed to be highly capable of distinguishing elite genotypes and pointing out the proper features for selection criteria. Bioinformatics results indicated that SOD is more important than other enzymatic antioxidant for being considered as selection criteria or candidate gene for transgenic purposes. Based on expressional results, Mn-SOD announced as a general isozyme that is probably highly expressed in most of the species, while, Cu/Zn-SOD was introduced as a genotype specific isozyme that is likely more expressed in tolerant genotypes.
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  • 文章类型: Journal Article
    目的:药物计量学模型为临床试验的合理设计提供了有用的工具。本研究评估了研究设计-,药物-,和患者相关的特征以及它们对显示基于药物基因组学(PGx)的剂量在骨髓毒性方面的益处的功效的影响的分析方法。
    方法:组装了两个药代动力学模型和一个骨髓抑制模型,以预测伊立替康及其代谢物SN-38的浓度,给予不同的UGT1A1基因型(差代谢者:CLSN-38:-36%)和中性粒细胞减少后常规与基于PGx的给药(350对245mg/m2(-30%))。在不同的情况下评估研究能力(n=50-400名患者/手臂,平行/交叉,不同大小的CLSN-38,暴露-反应关系,个体间变异性),并使用基于模型的数据分析与传统统计检验。
    结果:CLSN-38在代谢不良者中的减少幅度和SN-38的骨髓抑制效力显着影响显示4级中性粒细胞减少症(<0.5·109细胞/L)的能力。传统统计分析达到>80%的功效(χ2/McNemar检验,α=0.05),每个治疗组/序列(平行/交叉研究)需要220/100名患者。基于模型的分析导致相当小的总样本量(给定并行/交叉设计,n=100/15)以获得相同的统计功效。
    结论:所提出的发现可能有助于避免不可行的试验,并使药物遗传学研究的设计合理化。
    OBJECTIVE: Pharmacometric models provide useful tools to aid the rational design of clinical trials. This study evaluates study design-, drug-, and patient-related features as well as analysis methods for their influence on the power to demonstrate a benefit of pharmacogenomics (PGx)-based dosing regarding myelotoxicity.
    METHODS: Two pharmacokinetic and one myelosuppression model were assembled to predict concentrations of irinotecan and its metabolite SN-38 given different UGT1A1 genotypes (poor metabolizers: CLSN-38: -36%) and neutropenia following conventional versus PGx-based dosing (350 versus 245 mg/m2 (-30%)). Study power was assessed given diverse scenarios (n = 50-400 patients/arm, parallel/crossover, varying magnitude of CLSN-38, exposure-response relationship, inter-individual variability) and using model-based data analysis versus conventional statistical testing.
    RESULTS: The magnitude of CLSN-38 reduction in poor metabolizers and the myelosuppressive potency of SN-38 markedly influenced the power to show a difference in grade 4 neutropenia (<0.5·109 cells/L) after PGx-based versus standard dosing. To achieve >80% power with traditional statistical analysis (χ2/McNemar\'s test, α = 0.05), 220/100 patients per treatment arm/sequence (parallel/crossover study) were required. The model-based analysis resulted in considerably smaller total sample sizes (n = 100/15 given parallel/crossover design) to obtain the same statistical power.
    CONCLUSIONS: The presented findings may help to avoid unfeasible trials and to rationalize the design of pharmacogenetic studies.
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