principal component analyses

主成分分析
  • 文章类型: Journal Article
    骨髓炎是一种由细菌引起的骨骼疾病,可以损害骨骼。拉曼手持光谱法已经成为用于检测骨感染的有前途的诊断工具,并且可以在外科手术期间在术中使用。这项研究涉及来自40名患者的120个骨骼样本,有80个样本感染了金黄色葡萄球菌或表皮葡萄球菌。拉曼手持光谱法证明了健康和感染骨样品之间以及两种类型的细菌病原体之间的成功区分。拉曼手持光谱法似乎是骨感染的有前途的诊断工具,并且具有克服传统诊断程序的许多缺点的潜力。进一步研究,然而,需要确认其诊断能力并考虑其他因素,如病原体检测的极限和最佳校准标准。
    Osteomyelitis is a bone disease caused by bacteria that can damage bone. Raman handheld spectroscopy has emerged as a promising diagnostic tool for detecting bone infection and can be used intraoperatively during surgical procedures. This study involved 120 bone samples from 40 patients, with 80 samples infected with either Staphylococcus aureus or Staphylococcus epidermidis. Raman handheld spectroscopy demonstrated successful differentiation between healthy and infected bone samples and between the two types of bacterial pathogens. Raman handheld spectroscopy appears to be a promising diagnostic tool in bone infection and holds the potential to overcome many of the shortcomings of traditional diagnostic procedures. Further research, however, is required to confirm its diagnostic capabilities and consider other factors, such as the limit of pathogen detection and optimal calibration standards.
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  • 文章类型: Journal Article
    使用中红外光谱的骨分析越来越受欢迎,特别是手持光谱仪,只要数据质量符合标准,就可以进行现场测试。为了诊断人类骨移植物中的表皮葡萄球菌,进行这项研究是为了比较Agilent4300手持式傅立叶变换红外与PerkinElmerSpectrum100衰减全反射红外光谱台式仪器的有效性。该研究分析了40个未感染和10个感染表皮葡萄球菌的人类骨骼样本,收集650cm-1和4000cm-1之间的反射率数据,光谱分辨率为2cm-1(Agilent4300手持式)和0.5cm-1(PerkinElmerSpectrum100)。获取的光谱信息用于光谱和无监督分类,比如主成分分析。当使用推荐的设置和数据分析策略时,两种方法都产生了显著的结果,检测由于感染导致的骨质量损失。当存在组织短缺且时间至关重要时,MIR光谱学提供有价值的诊断工具。然而,必须进行更大样本量的进一步研究,以彻底验证其利弊。
    Bone analyses using mid-infrared spectroscopy are gaining popularity, especially with handheld spectrometers that enable on-site testing as long as the data quality meets standards. In order to diagnose Staphylococcus epidermidis in human bone grafts, this study was carried out to compare the effectiveness of the Agilent 4300 Handheld Fourier-transform infrared with the Perkin Elmer Spectrum 100 attenuated-total-reflectance infrared spectroscopy benchtop instrument. The study analyzed 40 non-infected and 10 infected human bone samples with Staphylococcus epidermidis, collecting reflectance data between 650 cm-1 and 4000 cm-1, with a spectral resolution of 2 cm-1 (Agilent 4300 Handheld) and 0.5 cm-1 (Perkin Elmer Spectrum 100). The acquired spectral information was used for spectral and unsupervised classification, such as a principal component analysis. Both methods yielded significant results when using the recommended settings and data analysis strategies, detecting a loss in bone quality due to the infection. MIR spectroscopy provides a valuable diagnostic tool when there is a tissue shortage and time is of the essence. However, it is essential to conduct further research with larger sample sizes to verify its pros and cons thoroughly.
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  • 文章类型: Journal Article
    猪繁殖与呼吸综合征病毒2型(PRRSV)的遗传多样性和新遗传变异的频繁出现阻碍了控制努力,然而PRRSV宏观进化模式的驱动因素仍然缺乏文献记载.利用>20,000orf5序列的综合数据库,我们的目标是根据PRRSV在美国共同传播的系统发育结构对变异进行分类,量化亚谱系出现的进化动力学,并描述亚谱系之间潜在的抗原差异。我们将最普遍的谱系(谱系1,约占可用序列的60%)细分为八个子谱系。贝叶斯合并SkyGrid模型用于估计每个子谱系随时间的有效种群规模。我们表明,每1到4年出现一个新的亚谱系,从出现到人口高峰之间的时间平均为4.5年(范围:2-8年)。确定了不同子谱系的顺序优势模式,大约每3年有一个新的占主导地位的子血统取代它的前身。每个亚谱系的共有氨基酸序列在与宿主免疫相关的关键GP5位点不同,这表明亚谱系更替可能与免疫介导的竞争有关。这对理解遗传多样性的驱动因素和美国新PRRSV变异的出现具有重要意义
    The genetic diversity and frequent emergence of novel genetic variants of porcine reproductive and respiratory syndrome virus type-2 (PRRSV) hinders control efforts, yet drivers of macro-evolutionary patterns of PRRSV remain poorly documented. Utilizing a comprehensive database of >20,000 orf5 sequences, our objective was to classify variants according to the phylogenetic structure of PRRSV co-circulating in the U.S., quantify evolutionary dynamics of sub-lineage emergence, and describe potential antigenic differences among sub-lineages. We subdivided the most prevalent lineage (Lineage 1, accounting for approximately 60% of available sequences) into eight sub-lineages. Bayesian coalescent SkyGrid models were used to estimate each sub-lineage\'s effective population size over time. We show that a new sub-lineage emerged every 1 to 4 years and that the time between emergence and peak population size was 4.5 years on average (range: 2-8 years). A pattern of sequential dominance of different sub-lineages was identified, with a new dominant sub-lineage replacing its predecessor approximately every 3 years. Consensus amino acid sequences for each sub-lineage differed in key GP5 sites related to host immunity, suggesting that sub-lineage turnover may be linked to immune-mediated competition. This has important implications for understanding drivers of genetic diversity and emergence of new PRRSV variants in the U.S.
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  • 文章类型: Journal Article
    进行了惰性和侵袭性淋巴瘤的中红外(MIR)显微成像,包括福尔马林固定和石蜡包埋的6个滤泡性淋巴瘤和12个弥漫性大B细胞淋巴瘤以及反应性淋巴结,以研究益处和挑战淋巴瘤诊断。将MIR图像与定义的病理特征进行比较,例如惰性,侵袭性和反应性,生发中心与活化细胞起源(COO)亚型,或低与高增殖指数和PD-L1表达水平。我们证明MIR显微成像可以区分反应性淋巴结,惰性和侵袭性淋巴瘤样本。此外,它有可能用于淋巴瘤的亚型,如COO亚型之间的区别所示,增殖水平和PD-L1表达。MIR显微成像是淋巴瘤诊断和分型的一种有前途的工具,需要进一步评估以充分探索这种方法用于病理诊断的优缺点。
    Mid-infrared (MIR) microscopic imaging of indolent and aggressive lymphomas was performed including formalin-fixed and paraffin-embedded samples of six follicular lymphomas and 12 diffuse large B-cell-lymphomas as well as reactive lymph nodes to investigate benefits and challenges for lymphoma diagnosis. MIR images were compared to defined pathological characteristics such as indolent versus aggressive versus reactive, germinal centre versus activated cell-of-origin (COO) subtypes, or a low versus a high proliferative index and level of PD-L1 expression. We demonstrated that MIR microscopic imaging can differentiate between reactive lymph nodes, indolent and aggressive lymphoma samples. Also, it has potential to be used in the subtyping of lymphomas, as shown with the differentiation between COO subtypes, the level of proliferation and PD-L1 expression. MIR microscopic imaging is a promising tool for diagnosis and subtyping of lymphoma and further evaluation is needed to fully explore the advantages and disadvantages of this method for pathological diagnosis.
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  • 文章类型: Journal Article
    微生物构成食物网的基础并驱动生物地球化学循环。由于相互作用的环境和性状组合的数量众多,预测微生物进化对全球元素循环的影响仍然是一个重大挑战。这里,我们提出了一种将多变量特征数据整合到特征进化预测模型中的方法。我们调查了使用来自暴露于高CO2的藻类衣藻的经验演化数据参数化的数千个可能的适应性行走的结果。我们发现,历史偏见的方向(现有的性状相关性)影响了适应率和进化的表型(性状组合)。严重的,我们使用直接从经验性状值得出的适应度景观来捕获已知的进化现象。这项工作表明,生态模型需要同时表示性状的变化和性状之间相关性的变化,以便准确捕获浮游植物的进化并预测元素循环的未来变化。
    Microbes form the base of food webs and drive biogeochemical cycling. Predicting the effects of microbial evolution on global elemental cycles remains a significant challenge due to the sheer number of interacting environmental and trait combinations. Here, we present an approach for integrating multivariate trait data into a predictive model of trait evolution. We investigated the outcome of thousands of possible adaptive walks parameterized using empirical evolution data from the alga Chlamydomonas exposed to high CO2. We found that the direction of historical bias (existing trait correlations) influenced both the rate of adaptation and the evolved phenotypes (trait combinations). Critically, we use fitness landscapes derived directly from empirical trait values to capture known evolutionary phenomena. This work demonstrates that ecological models need to represent both changes in traits and changes in the correlation between traits in order to accurately capture phytoplankton evolution and predict future shifts in elemental cycling.
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  • 文章类型: Journal Article
    这项研究的目的是对Akkaraman的胎盘特征进行分类,Morkaraman,Karayaka,Awassi,马利亚,和巴夫拉绵羊品种采用层次聚类方法。总的来说,240个单独的数据记录被用作实验材料。胎盘特征,如子叶总表面积,小子叶和大子叶长度,小子叶深度,等。被用作解释变量来对品种特征进行分类。分层聚类与欧几里得距离最近邻方法一起使用,以对绵羊品种的变异进行分类。因此,六个品种被分成三个集群:第一个集群由巴夫拉组成,Karayaka,和Awassi品种;第二个由Akkaraman和Malya品种组成;第三组仅包括Morkaraman品种。巴夫拉和卡拉亚卡被认为是最近的品种,在胎盘特征方面的相似性为98.7%。Akkaraman和Malya品种的相似率为97.5%,而Bafra的比例为96.8%,Karayaka,和Awassi品种。Akkaraman的相似之处,Karayaka,Awassi,马利亚,巴夫拉绵羊的品种估计为95.7%。发现绵羊品种之间的总体相似性为93.2%。这项研究的结果可能是有用的选择工具的繁殖和可用于选择品种的饲养。
    The aim of this study was to classify placental characteristics of Akkaraman, Morkaraman, Karayaka, Awassi, Malya, and Bafra sheep breeds using the hierarchical clustering method. In total, 240 individual data records were used as experimental material. Placental characteristics such as total cotyledon surface area, small and large cotyledon length, small cotyledon depth, etc. were used as explanatory variables to classify the breeds\' characteristics. Hierarchical clustering was used with the nearest neighbour method with Euclidean distance in order to classify the sheep breeds\' variations. As a result, six breeds were separated into three clusters: the first cluster consisted of Bafra, Karayaka, and Awassi breeds; the second consisted of Akkaraman and Malya breeds; and the third cluster included only the Morkaraman breed. Bafra and Karayaka were pointed as the nearest breeds, with a similarity of 98.7% in terms of placental characteristics. The similarity rate of the Akkaraman and Malya breeds was at a level of 97.5%, whereas it was 96.8% for Bafra, Karayaka, and Awassi breeds. The similarity of Akkaraman, Karayaka, Awassi, Malya, and Bafra sheep breeds was estimated as 95.7%. The overall similarity was found to be at a level of 93.2% among sheep breeds. The outcomes of the study might be useful as a selection tool for reproductivity and can be used to select the breed to be reared.
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  • 文章类型: Journal Article
    Environmental conditions affect crop yield, and water deficit has been highlighted by the negative impact on soybean grain production. Radicial growth in greater volume and depth can be an alternative to minimize losses caused by a lack of water. Therefore, knowledge of how soybean roots behave before the chemical, physical, and biological attributes of the soil can help establish managements that benefit in-depth root growth. The objective was to evaluate the growth of soybean roots in response to chemical, physical, and biological variations in the soil, in different soil locations and depths. Six experiments were conducted in different locations. Soil samples were collected every 5 cm of soil up to 60 cm of soil depth for chemical, physical, and biological analysis. The roots were collected every 5 cm deep up to 45 cm deep from the ground. The six sites presented unsatisfactory values of pH and organic matter, and presented phosphorus, potassium, and calcium at high concentrations in the first centimeters of soil depth. The total porosity of the soil was above 0.50 m3 m-3, but the proportion of the volume of macropores, micropores, and cryptopores resulted in soils with resistance to penetration to the roots. Microbial biomass was higher on the soil surface when compared to deeper soil layers, however, the metabolic quotient was higher in soil depth, showing that microorganisms in depth have low ability to incorporate carbon into microbial biomass. Root growth occurred in a greater proportion in the first centimeters of soil-depth, possibly because the soil attributes that favor the root growth is concentrated on the soil surface.
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  • 文章类型: Journal Article
    Heterogeneous clinical characteristics are observed in acquired isolated adrenocorticotropic hormone (ACTH) deficiency (IAD); however, its classification remains to be established because of its largely unknown pathophysiology. In IAD, anti-pituitary antibodies have been detected in some patients, although their significance remains unclear. Therefore, this study aimed to classify patients with IAD and to clarify the significance of anti-pituitary antibodies.
    We analyzed 46 consecutive patients with IAD. Serum anti-pituitary antibodies were analyzed via immunofluorescence staining using a mouse pituitary tissue. Principal component and cluster analyses were performed to classify IAD patients based on clinical characteristics and autoantibodies.
    Immunofluorescence analysis using the sera revealed that 58% of patients showed anti-corticotroph antibodies and 6% of patients showed anti-follicular stellate cell (FSC) antibodies. Principal component analysis demonstrated that three parameters could explain 70% of the patients. Hierarchical cluster analysis showed three clusters: Groups A and B comprised patients who were positive for anti-corticotroph antibodies, and plasma ACTH levels were extremely low. Groups A and B comprised middle-aged or elderly men and middle-aged women, respectively. Group C comprised patients who were positive for the anti-FSC antibody and elderly men; plasma ACTH levels were relatively high.
    Patients with IAD were classified into three groups based on clinical characteristics and autoantibodies. The presence of anti-corticotroph antibody suggested severe injury to corticotrophs. This new classification clearly demonstrated the heterogeneity in the pathogenesis of IAD.
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  • 文章类型: Journal Article
    Aphasia classifications and specialized language batteries differ across the fields of neurodegenerative disorders and lesional brain injuries, resulting in difficult comparisons of language deficits across etiologies. In this study, we present a simplified framework, in which a widely-used aphasia battery captures clinical clusters across disease etiologies and provides a quantitative and visual method to characterize and track patients over time. The framework is used to evaluate populations representing three disease etiologies: stroke, primary progressive aphasia (PPA), and post-operative aphasia. A total of 330 patients across three populations with cerebral injury leading to aphasia were investigated, including 76 patients with stroke, 107 patients meeting criteria for PPA, and 147 patients following left hemispheric resective surgery. Western Aphasia Battery (WAB) measures (Information Content, Fluency, answering Yes/No questions, Auditory Word Recognition, Sequential Commands, and Repetition) were collected across the three populations and analyzed to develop a multi-dimensional aphasia model using dimensionality reduction techniques. Two orthogonal dimensions were found to explain 87% of the variance across aphasia phenotypes and three disease etiologies. The first dimension reflects shared weighting across aphasia subscores and correlated with aphasia severity. The second dimension incorporates fluency and comprehension, thereby separating Wernicke\'s from Broca\'s aphasia, and the non-fluent/agrammatic from semantic PPA variants. Clusters representing clinical classifications, including late PPA presentations, were preserved within the two-dimensional space. Early PPA presentations were not classifiable, as specialized batteries are needed for phenotyping. Longitudinal data was further used to visualize the trajectory of aphasias during recovery or disease progression, including the rapid recovery of post-operative aphasic patients. This method has implications for the conceptualization of aphasia as a spectrum disorder across different disease etiology and may serve as a framework to track the trajectories of aphasia progression and recovery.
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  • 文章类型: Journal Article
    Radiation-induced mucositis is a severe acute side effect, which can jeopardize treatment compliance and cause weight loss during treatment. The study aimed to develop robust models to predict the risk of severe mucositis.
    Mucosal toxicity scores were prospectively recorded for 802 consecutive Head and Neck (H&N) cancer patients and dichotomised into non-severe event (grade 0-2) and severe event (grade 3+) groups. Two different model approaches were utilised to evaluate the robustness of the models. These used LASSO and Best Subset selection combined with 10-fold cross-validation performed on two-thirds of the patient cohort using principal component analysis of DVHs. The remaining one-third of the patients were used for validation. Model performance was tested through calibration plot and model performance metrics.
    The main predicted risk factors were treatment acceleration and the first two principal dose components, which reflect the mean dose and the balance between high and low doses to the oral cavity. For the LASSO model, gender and current smoker status were also included in the model. The AUC values of the two models on the validation cohort were 0.797 (95%CI: 0.741-0.857) and 0.808 (95%CI: 0.749-0.859), respectively. The two models predicted very similar risk values with an internal Pearson coefficient of 0.954, indicating their robustness.
    Robust prediction models of the risk of severe mucositis have been developed based on information from the entire dose distribution for a large cohort of patients consisting of all patients treated H&N for within our institution over a five year period.
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