Rolling enrollment is a common method for participant recruitment in medical practice. In the longitudinal data, where researchers are often interested in outcomes occurring after a certain period of treatment, the definition of causal effects differs from that in the cross-sectional data. It poses new challenges for the application of matching methods in the longitudinal studies. Longitudinal matching is an extension of matching methods in longitudinal studies involving static interventions such as rolling enrollment. Currently, longitudinal matching methods are widely applied in the comparative effectiveness research. This article elucidates the fundamental principles, applicable conditions, code implementation, and application instances of four longitudinal matching methods through theoretical discussions and empirical illustrations. It provides methodological references for estimating causal effects in longitudinal data analysis.
ObjectiveTo systematically review the comprehensive evaluation methods applied to estimate the medical service performance based on diagnosis-related groups (DRGs) in China and to provide suggestions for the promotion of methods in further studies.MethodsLiterature published before May 2019 were searched in China National Knowledge Infrastructure, WanFang Data, CQVIP and PubMed for studies about DRGs-based comprehensive evaluation. After literature screening and information extracting by two reviewers independently, qualitative approaches were used to describe the application of DRGs-based comprehensive evaluation methods in the performance evaluation of medical services.ResultsA total of 24 articles were included in the systematic review. Different indexes were used to evaluate the medical service performance. Delphi Method, expert discussion, Saaty’s Method and some other means were applied to determine the weights of indexes in 8 articles. Rank-sum ratio method, Technique for Order Preference by Similarity to an Ideal Solution and synthetic index method were proposed for the comprehensive evaluation in 9, 7 and 9 articles, respectively; besides, analytic hierarchy process and combination evaluation were also used.ConclusionsBased on DRGs, the choose of indicators, weighting approaches, and calculation methods of comprehensive values vary richly in different studies. More attention should be paid to weight using and combination of comprehensive evaluation methods in further studies. Meanwhile, the quality of information source used for estimation and the rationality of results application are supposed to be emphasized.
The main approaches to medical education reform that have been introduced elsewhere in the world, including the integration of basic and clinical sciences into organ-based model, the establishment of a Center for Faculty Development and problem-based learning (PBL) have been introduced to the College of Medicine, Chung Shan Medical University (CSMU) since the mid 1990s. The process of developing the PBL approach can be divided into the following stages: Observation (1994-2000): In this stage, CSMU observed the practice and effectiveness of PBL programs in other domestic and foreign medical schools. At the same time, we assessed the possibility of introducing PBL to Chung Shan. When the authority decided to introduce PBL, a PBL committee was inaugurated. Preparation (2000-2002): In this stage, tutor training took place, as well as PBL case writing workshops to reach consensus among the faculty. To reduce the total amount of curricula and traditional teaching hours, we combined and simplified related curricula, so that one and half weekdays were reserved for PBL tutorials and students’ self-study. A preliminary course about how to learn well, including the philosophy and methodology of learning as well as evidence-based medicine (EBM), was integrated into premedical curricula. Practice (2002-2004): In light of the number of trained tutors and written cases that have been prepared, and the desire that the PBL would be successful from the start, CSMU chose to introduce PBL to the clinical curricula first in a hybrid curriculum design. This meant that the traditional teaching was retained at the beginning. Evaluation of PBL by the students was done at the end of each semester. Tutor meetings were held twice per semester. Advancement (2004-2006): In this stage, PBL was introduced to the basic medical curricula as well as to the premedical general curricula. Based on our experience and comprehensive evaluation, a PBL guidebook for tutors and students has been published and delivered to both groups. We also developed an on-line evaluation system containing the evaluation forms for students and tutors. Excellence (2006 onwards): In this stage, the PBL website and learning resources will be further developed, and we are designing the system for on-line PBL practice.In conclusion, the introduction to PBL for medical education is reasonable and feasible. It requires b administrative support, a long-standing and high commitment of the PBL committee, consensus among the faculty and an appropriate planning and evaluation mechanism.
ObjectiveTo explore the value on excision of subpyloric (No.6 group) lymph nodes of stomach by detection of metastatic rate and metastasis of lymph nodes of No.6 group and its subgroups. MethodsThe clinical data including complete information on No.6 group and its subgroups lymph nodes in 80 patients underwent gastrectomy and subpyloric lymph nodes dissection for gastric cancer from January 2006 to December 2009 were retrospectively analyzed. Referring to the right gastroepiploic vein, the No.6 lymph nodes were divided into three subgroups (No.6a, No.6b, and No.6c subgroup), and the relationship between the metastasis of No.6 lymph nodes and clinicopathologic features as well as the metastasis of No.7, No.8a， and No.9 lymph nodes were analyzed by logistic regression analysis. ResultsThe metastatic rate of No.6 group lymph nodes was 41.3% (33/80) and with 26.0% (108/415) of the resected lymph nodes involved. The metastatic rate of lymph nodes in No.6a subgroup (7.5%, 6/80) was significantly lower than that in No.6b (16.3%, 13/80) and No.6c subgroup (36.3%, 29/80), Plt;0.001. The metastasis of the resected lymph nodes in No.6a, No.6b, and No.6c subgroup was 25.0% (8/32), 17.6% (13/74), and 28.2% (87/309), respectively, and the difference was not significant (P=0.292). The metastasis of lymph nodes in No.6a subgroup was correlated to T stage (P=0.042) and N stage (P=0.006). The metastasis of lymph nodes in No.6b subgroup was correlated to N stage (P=0.002) and TNM stage (P=0.013). The metastasis of lymph nodes in No.6c subgroup was correlated to differentiation degree of tumor (P=0.008), T stage (P=0.003), N stage (P=0.000), and TNM stage (P=0.000). The logistic regression analysis showed that the metastasis of lymph nodes was correlated to the metastasis of No.8a lymph nodes (P=0.023) and N stage (P=0.002) in No.6 group, the metastasis of No.8a lymph nodes (P=0.018) in No.6a subgroup, N stage (P=0.005) in No.6b subgroup, and the metastasis of No.8a lymph nodes (P=0.016) and N stage (P=0.004) in No.6c subgroup. ConclusionAttentions should be paid to the complete dissection of subpyloric lymph nodes in gastric cancer surgery, especially for the lymph nodes of No.6a and No.6b subgroups.
The paper presents two statistical methods to compare summary estimates of different subgroups in meta-analysis. It also shows how to use Z test and meta-regression model with dichotomous data and continuous data in R software to explain the similarities and differences between the two statistical methods by examples.
High mobility group box 1 (HMGB1) is widely expressed in mammalian tissues and cells which is involved in various pathophysiological processes such as inflammation, autophagy, and apoptosis, and plays an important role in maintaining cell survival and normal function. HMGB1 plays an important part in the development of stroke, which can affect the prognosis by inducing neuroinflammation and autophagy. HMGB1 may have a bidirectional effect in acute and chronic phases. Exploring the specific role and mechanism of HMGB1 in each stage of stroke may make it a new target for prevention and treatment in the future.
Objective To investigate the effect of microRNA-22-3p (miR-22-3p) on the inflammation of human pulmonary microvascular endothelial cells (HPMEC) induced by lipopolysaccharide (LPS) by regulating the HMGB1/NLRP3 pathway. Methods miRNA microarray was taken from peripheral blood of patients with acute respiratory distress syndrome (ARDS) caused by abdominal infection and healthy controls for analysis, and the target miRNA was selected. miRNA mimics, inhibitor and their negative controls were transfected in HPMECs which were stimulated with LPS. Real time fluorescent quantitative polymerase chain reaction (RT-qPCR) and Western blot were used to detect the mRNA and protein levels of high mobility group box-1 protein (HMGB1) and nucleotide binding oligomerization segment like receptor family 3 (NLRP3). RT-qPCR and enzyme linked immunosorbent assay were used to detect the levels of inflammatory factors in the cells and supernatant. Results miRNA microarray showed that miR-22-3p was down-regulated in the plasma of patients with ARDS. Compared with the negative control group, after miR-22-3p over-expression, the protein and mRNA levels of HMGB1 and NLRP3 decreased significantly. Similarly, the level of cleaved-caspase-1 decreased significantly. At the same time, interleukin (IL)-6, IL-8 and IL-1β mRNA level in cytoplasm and supernatant were down-regulated by miR-22-3p mimics. After transfected with miR-22-3p inhibitor, the expression levels of HMGB1, NLRP3, caspase-1 protein and inflammatory factors were significantly up-regulated. Conclusion miR-22-3p is significantly downregulated in peripheral blood of ARDS patients caused by abdominal infection, which can inhibit the expression of HMGB1 and NLRP3 and its downstream inflammatory response in HPMECs.
Subpopulation treatment effect pattern plot (STEPP) method is a method for examining the relationship between treatment effects and continuous covariates and is characterized by dividing the study population into multiple overlapping subpopulations to be analyzed based on continuous covariate values. STEPP method has a different purpose than traditional subgroup analyses, and STEPP has a clear advantage in exploring the relationship between treatment effects and continuous covariates. In this study, the concepts, advantages, and subpopulation delineation methods of the STEPP method are introduced, and the specific operation process and result interpretation methods of STEPP method analysis using the STEPP package in R language are presented with examples.
Objective To study the effect on expression of high mobility group box-1 （HMGB1） mRNA for the expression of zonula occludens-1 （ZO-1） in ileum tissues， and to explore the possible mechanism of intestinal mucosal barrier injury in rats with acute necrotizing pancreatitis （ANP）. Methods Ninety-six male Wistar rats were divided randomly （random number method） into ANP group， ethyl pyruvate （EP）group， and sham operation group. Eight rats of 3 groups were killed to get abdominal aortic blood and ileal tissues at 6， 12， 24， and 48h after operation， respectively.The levels of plasma amylase （AMY） ， D-lactate acid， and the activity of malonyl dialdehyde （MDA） in the ileum tissues were determined by using automatic biochemical analyzer， improved enzymatic spectrophotometry， and thiobarbituric acid （TAB） colorimetry respectively. The pathological changes of ileum tissues were observed under microscopy by HE staining， the expression of ZO-1 protein in ileum tissues was observed by immunohistochemistry （SP method）， and the expressions of HMGB1 mRNA and ZO-1 mRNA in ileum tissues were detected by reverse transcription-polymerase chain reaction （RT-PCR）. Results Compared with ANP group at the same time， levels of AMY， D-lactate acid， and MDA in ileum tissues of EP group were all significantly lower （P＜0.05）. The expression level of HMGB1 mRNA increased at 6 h while ZO-1 mRNA decreased in ANP group. Compared with ANP group at the same time， the expression level of HMGB1 mRNA of EP group was significantly lower while ZO-1 mRNA was higher （P＜0.05）， and the pathological damage in ileum tissues was lighter. Conclusions The decreased expression of ZO-1 in ileum tissues is one of the vitalcauses for intestinal mucosal barrier injury in ANP， and it probably occurs in case of the excessive expression of HMGB1.
Cognitive reappraisal is an important strategy for emotion regulation. Studies show that even healthy people may not be able to implement this strategy successfully, but the underlying neural mechanism behind the behavioral observation of success or failure of reappraisal is unclear. In this paper, 28 healthy college students participated in an experiment of emotional regulation with the cognitive reappraisal strategy. They were asked to complete the cognitive psychological questionnaires before the experiment. Their behavioral scores and scalp electroencephalogram (EEG) signals were collected simultaneously during the experiment. We divided all the subjects into two groups, according to the statistical test of valence scores. Then we analyzed their questionnaires, early event-related potential (ERP) components N200, P200, and late positive potential (LPP), and calculated the correlation between the valence score and the amplitude of LPP. The results showed that, in both groups, compared with negative-watching, the reappraisal induced larger N200 and P200 components and there were two modulation patterns (“increase” and “decrease”) of the reappraisal effect on the amplitude of early LPP (300−1 000 ms after stimulus onset). Moreover, correlation analysis showed that significant positive correlation between two differences in the successful group, i.e., the greater difference in the valence scoresin between reappraisal and negative-watching, the greater difference in the amplitude of early LPP between reappraisal and negative-watching; but no such effect was found in the failure group. These results indicated that, whether reappraisal was successful or not, no significant effect on early ERP components was found; and there were different patterns of the reappraisal effect on early LPP. The difference between successful and failure groups was mainly reflected in early LPP, that is, the EEG characteristics and behavioral scores of successful group were significantly positively correlated. Furthermore, the small sample analysis showed that this correlation only existed in the pattern of "increase". In the future, more research of this modulation mode is necessary in order to find more stable EEG characteristics under successful cognitive reappraisal in emotion regulation.