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1.
ObjectiveTo explore the protective effect and potential mechanisms of danshen root (Salvia miltiorrhiza Bge., S. miltiorrhiza) and its extracts for the treatment of diabetic nephropathy (DN).MethodsPreclinical studies of S. miltiorrhiza and its extracts on DN were systematically searched in nine databases. The primary outcomes were blood glucose, kidney function, proteinuria, and renal histopathology. The secondary outcomes included the related mechanisms. The methodological quality of animal studies was assessed based on the risk of bias tool of the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) for animal studies. Meta-analysis was performed using R software (version 4.1.2).ResultsTwenty-nine animal experimental studies that met the eligibility criteria were included in this study. Compared to the control group, S. miltiorrhiza reduced the serum creatinine, blood urea nitrogen, 24-h urine protein, 24-h urine albumin, blood glucose, and kidney index (kidney weight/body weight), and alleviated renal pathological damage. In terms of the mechanism of action, compared to the control group, S. miltiorrhiza reduced the levels of transforming growth factor β1, collagen IV, malondialdehyde, tumor necrosis factor α, interleukin-6, and monocyte/macrophage (ED-1), and increased the levels of superoxide dismutase, glutathione peroxidase, nuclear factor E2–related factor 2, and heme oxygenase-1.ConclusionThe existing evidence shows that S. miltiorrhiza has beneficial effects on the animal model of DN, and its mechanism is mainly related to improving kidney fibrosis, oxidative stress, and inflammatory response.  相似文献   
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There is a critical need to develop animal models to alleviate vaccine and drug development difficulties against zoonotic viral infections. The coronavirus family, which includes severe acute respiratory syndrome coronavirus 1 and severe acute respiratory syndrome coronavirus 2, crossed the species barrier and infected humans, causing a global outbreak in the 21st century. Because humans do not have pre-existing immunity against these viral infections and with ethics governing clinical trials, animal models are therefore being used in clinical studies to facilitate drug discovery and testing efficacy of vaccines. The ideal animal models should reflect the viral replication, clinical signs, and pathological responses observed in humans. Different animal species should be tested to establish an appropriate animal model to study the disease pathology, transmission and evaluation of novel vaccine and drug candidates to treat coronavirus disease 2019. In this context, the present review summarizes the recent progress in developing animal models for these two pathogenic viruses and highlights the utility of these models in studying SARS-associated coronavirus diseases.  相似文献   
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To determine prognostic factors for postoperative velopharyngeal function following the primary cleft palate repair at the age of five and above.This study reviewed patients with cleft palate who had undergone Furlow palatoplasty at age 5 or older from 2009 to 2014. We obtained intraoperative measurements, including velar length, pharyngeal depth, cleft width, maxillary width, cleft palate index (cleft width/maxillary width) and palatopharyngeal ratio (velar length/pharyngeal depth), as well as speech evaluation results at least 1 year after surgery. Logistic regression and retrospective analyses were performed to determine factors associated with speech performance after the primary cleft palate repair.Among the six intraoperative measurements of velopharyngeal morphology, only pharyngeal depth was incorporated into the regression model, and was found to have an inverse association with postoperative velopharyngeal function, Exp (B) 0.883 (95% CI 0.798-0.976). Moreover, a pharyngeal depth greater than 16 mm was significantly associated with a higher risk of postoperative velopharyngeal insufficiency (P < 0.01).Pharyngeal depth is potentially a prognostic indicator for the primary management of cleft palate in older patients. Pharyngoplasty may need to be considered when the pharyngeal depth is large and the patient’s access to surgery is limited.  相似文献   
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目的 建立结肠癌人源性肿瘤组织异种移植(patient-derived xenograft,PDX)模型并研究其在化疗药物筛选中的应用价值。 方法 将新鲜的人结肠癌手术标本移植于BAIB/c裸小鼠皮下建立结肠癌PDX模型,稳定传至第3代;将PDX模型肿瘤组织与人肿瘤组织H&E染色,比较其组织形态特征;免疫组织化学检测肿瘤组织癌胚抗原(carcino-embryonic antigen, CEA)的表达水平;绘制PDX模型肿瘤生长曲线;使用PDX模型评估临床用药伊利替康(Irinotecan,CPT-11)、5-氟尿嘧啶(5-Fluorouracil, 5-FU)和奥沙利铂(Oxaliplatin,OXA)的治疗效果及安全性;对比PDX模型对照组与治疗组血浆CEA表达水平。 结果 成功建立3例结肠癌PDX模型,肿瘤组织基本保持了原发瘤组织的形态,其CEA表达水平与人肿瘤组织基本一致。3例PDX模型均显示,CPT-11、5-FU、OXA治疗具有显著效果(P<0.05),其中CPT-11组效果最显著,其次是5-FU和OXA。D34562和D34603模型均显示OXA对小鼠体重影响较大,而CPT-11和5-FU相对安全。CPT-11、5-FU和OXA治疗均可降低PDX模型血浆CEA水平(P<0.05),且CPT-11组CEA水平明显低于5-FU和OXA组(P<0.05),样本D34562、D34603的5-FU组血浆CEA水平明显低于OXA组(P<0.05)。 结论 结肠癌PDX模型较好地保持了人源肿瘤组织的特征,CPT-11表现出良好的治疗效果且安全性高。  相似文献   
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This study aimed to clarify whether the pattern recognition involved in scoring proliferation fractions can be trained by abstract computerized images of virtual tissues. Twenty computer-generated images with randomly distributed blue or red dots were scored by 12 probands (all co-workers or collaborators of the Institute of Pathology, University of Bonn). Afterward, the probands underwent a training phase during which they received an immediate feedback on the actual rate of positivity after each image. Finally, the initial testing series was rescored. In a second round with 15 different probands, 20 Ki-67 immunohistochemistry images of tonsil tissue were scored, followed by the same training phase with computer-generated images, before the immunohistochemistry slides were scored again. Paired t-tests were used to compare the differences in mean rates pre- and post-training. Concerning computerized images, untrained probands scored the percentages of positive dots with a mean deviation from the true rates of 8.2%. Following training, the same testing series was scored significantly better with a mean deviation of 4.9% (mean improvement 3.3%, p < 0.001). Scoring real immunohistochemistry slides, the training with computerized images also improved correct estimations, albeit to a lesser degree (mean improvement 1%, p = 0.03). Abstract computerized images of virtual tissues may be a useful tool to train and improve the accuracy of pattern recognition involved in semiquantitative scoring of immunohistochemistry slides. As a side results, this study highlights the value of computer-generated images to verify the performance of image-analysis software.  相似文献   
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Many prospective biomedical studies collect longitudinal clinical and lifestyle data that are both continuous and discrete. In some studies, there is interest in the association between a binary outcome and the values of these longitudinal measurements at a specific time point. A common problem in these studies is inconsistency in timing of measurements and missing follow-ups which can lead to few measurements at the time of interest. Some methods have been developed to address this problem, but are only applicable to continuous measurements. To address this limitation, we propose a new class of joint models for a binary outcome and longitudinal explanatory variables of mixed types. The longitudinal model uses a latent normal random variable construction with regression splines to model time-dependent trends in mean with a Dirichlet Process prior assigned to random effects to relax distribution assumptions. We also standardize timing of the explanatory variables by relating the binary outcome to imputed longitudinal values at a set time point. The proposed model is evaluated through simulation studies and applied to data from a cancer survivor study of participants in the Women's Health Initiative.  相似文献   
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《Diagnostic Histopathology》2022,28(11):493-500
After decades of relative stagnation lung cancer is emerging as a disease type where rapid progress is being made in diagnosis and therapy, as well as in our understanding of disease biology. Much of this progress is of immediate impact to diagnosticians, and more is likely to affect diagnostic practice in the near future. In this review we seek to briefly summarize several key areas of active research of immediate or probable imminent value to trainee and consultant pulmonary pathologists alike. We cover some major changes in tumour classification, grading, and patient stratification, as well as considering the state of the art in machine-assisted interpretation of lung cancer histology, and the use of genetically modified lung cancer models.  相似文献   
10.

Objective

To examine the experience of interracial anxiety among health professionals and how it may affect the quality of their interactions with patients from racially marginalized populations. We explored the influence of prior interracial exposure—specifically through childhood neighborhoods, college student bodies, and friend groups—on interracial anxiety among medical students and residents. We also examined whether levels of interracial anxiety change from medical school through residency.

Data Source

Web-based longitudinal survey data from the Medical Student Cognitive Habits and Growth Evaluation Study.

Study Design

We used a retrospective longitudinal design with four observations for each trainee. The study population consisted of non-Black US medical trainees surveyed in their 1st and 4th years of medical school and 2nd and 3rd years of residency. Mixed effects longitudinal models were used to assess predictors of interracial anxiety and assess changes in interracial anxiety scores over time.

Principal Findings

In total, 3155 non-Black medical trainees were followed for 7 years. Seventy-eight percent grew up in predominantly White neighborhoods. Living in predominantly White neighborhoods and having less racially diverse friends were associated with higher levels of interracial anxiety among medical trainees. Trainees' interracial anxiety scores did not substantially change over time; interracial anxiety was highest in the 1st year of medical school, lowest in the 4th year, and increased slightly during residency.

Conclusions

Neighborhood and friend group composition had independent effects on interracial anxiety, indicating that premedical racial socialization may affect medical trainees' preparedness to interact effectively with diverse patient populations. Additionally, the lack of substantial change in interracial anxiety throughout medical training suggests the importance of providing curricular tools and structure (e.g., instituting interracial cooperative learning activities) to foster the development of healthy interracial relationships.  相似文献   
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