ABSTRACT
INTRODUCTION: The prevention and control of hospital-acquired infections remain a significant challenge worldwide, as textiles used in hospital wards are highly involved in transmission processes. This paper reports a new antibacterial medical fabric used to prepare hospital pillowcases, bottom sheets and quilt covers for controlling and reducing hospital-acquired infections. METHOD: The medical fabric was composed of blended yarns of staple polyester (PET) and degradable poly(3-hydroxybutyrate co-3-hydroxyvalerate) (PHBV)/polylactic acid (PLA) fibres, which were coated with polylactide oligomers (PLAO), which are environmentally friendly and safe antimicrobial agents with excellent thermal stability in high-temperature laundry. A clinical trial was conducted, with emphasis on the bacterial species that were closely related to the infection cases in the study hospital. RESULT: After 7 days of use, 94% of PET/PHBV/PLA-PLAO fabric retained <20 colony-forming units/100 cm2 of the total bacterial amount, meeting hygiene and cleanliness standards. CONCLUSION: This study demonstrates the potential of fabrics containing polyhydroxyalkanoate oligomers as highly effective, safe and long-lasting antimicrobial medical textiles that can effectively reduce the incidence of hospital-acquired infections.
Subject(s)
Anti-Bacterial Agents , Cross Infection , Polyhydroxyalkanoates , Textiles , Humans , Textiles/microbiology , Cross Infection/prevention & control , Anti-Bacterial Agents/pharmacology , Polyhydroxyalkanoates/pharmacology , Polyhydroxyalkanoates/chemistry , Polyesters/chemistry , Bacteria/drug effectsABSTRACT
Statistical graphics has a long history and is an important mean to present study design, analysis results and conclusions of medical research. A survey of statistical graphs of recent publications in Chinese and English academic journals shows that scientific and technical specifications of statistical graphics are still lacking. Based on the requirements of statistical graphics in prestigious medical journals (NEJM, Lancet, JAMA and The BMJ), this paper summarizes the technical requirements, key points of design of statistical graphs and practical conditions of common statistical graphs to provide reference for clinical researchers.
Subject(s)
Biomedical Research , Humans , Research Personnel , Research Design , Asian PeopleABSTRACT
Objective: To explore the consistency of peripheral whole blood and venous serum procalcitonin (PCT) levels, and the value of peripheral whole blood PCT in evaluating pediatric bacterial infection. Methods: This multicenter cross-sectional parallel control study was conducted in 11 children's hospital. All the 1 898 patients older than 28 days admitted to these hospitals from March 2018 to February 2019 had their peripheral whole blood and venous serum PCT detected simultaneously with unified equipment, reagent and method. According to the venous serum PCT level, the patients were stratified to subgroups. Analysis of variance and chi-square test were used to compare the demographic characteristics among groups. And the correlation between the peripheral blood and venous serum PCT level was investigated by quantitative Pearson correlation analysis.The PCT resultes were also converted into ranked data to further test the consistency between the two sampling methods by Spearman's rank correlation test. Furthermore, the ranked data were converted into binary data to evaluate the consistency and investigate the best cut-off of peripheral blood PCT level in predicting bacterial infection. Results: A total of 1 898 valid samples were included (1 098 males, 800 females),age 27.4(12.2,56.7) months. There was a good correlation between PCT values of peripheral whole blood and venous serum (r=0.97, P<0.01). The linear regression equation was PCTvenous serum=0.135+0.929×PCTperipheral whole blood. However, when stratified to 5 levels, PCT results showed diverse and unsatisfied consistency between the two sampling methods (r=0.51-0.92, all P<0.01). But after PCT was converted to ordinal categorical variables, the stratified analysis showed that the coincidence rate of the measured values by the two sampling methods in each boundary area was 84.9%-97.1%. The dichotomous variables also showed a good consistency (coincidence rate 96.8%-99.3%, Youden index 0.82-0.89). According to the severity of disease, the serum PCT value was classified into 4 intervalsï¼<0.5ã0.5-<2.0ã2.0-<10.0ã≥10.0 µg/Lï¼, and the peripheral blood PCT value also showed a good predictive value (AUC value was 0.991 2-0.997 9). The optimal cut points of peripheral whole blood PCT value 0.5ã1.0ã2.0ã10.0 µg/L corresponding to venous serum PCT values were 0.395, 0.595, 1.175 and 3.545 µg/L, respectively. Conclusions: There is a good correlation between peripheral whole blood PCT value and the venous serum PCT value, which means that the peripheral whole blood PCT could facilitate the identification of infection and clinical severity. Besides, the sampling of peripheral whole blood is simple and easy to repeat.
Subject(s)
Procalcitonin , Sepsis , Biomarkers , C-Reactive Protein , Calcitonin , Child, Preschool , Cross-Sectional Studies , Female , Humans , Infant , Male , Prognosis , ROC Curve , Retrospective StudiesABSTRACT
Objective: To study the correlation between systemic inflammation level and emphysema degree and bone mineral density in chronic obstructive pulmonary disease (COPD) patients and its possible mechanism. Methods: 90 patients with stable COPD who met the inclusion criteria and 50 controls in the physical examination center during the same period were recruited. All the enrolled objects have collected general clinical data, analyzed peripheral blood samples, measuring the Low-attenuation area of lung and CT value of lumbar 1 vertebra (L1-CT) by chest spiral CT. According to LAA%, COPD patients were divided into 36 cases of the non-emphysema group, 32cases of mild to moderate emphysema group, and 22 cases of severe emphysema group. The correlation between L1-CT value, LAA%, peripheral blood inflammatory factors, and pulmonary function indices in each group was analyzed and compared. Results: The HU value of L1-CT (107±32) in the COPD group was significantly lower than that in the control group (153±30), and the difference was statistically significant (P<0.05). The higher the LAA% in COPD patients was, the lower the value of L1-CT was, and the difference between groups was statistically significant. Compared with COPD patients in the non-emphysema group, peripheral blood neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), and C-reactive protein (CRP) were all increased in the emphysema group, and the differences were statistically significant (P<0.05). L1-CT was negatively correlated with LAA, PLR, NLR, and CRP while uncorrelated with serum concentration of calcium and phosphorus. Conclusion: The decrease in bone density in COPD patients is closely related to the degree of emphysema. It is associated with increased levels of systemic inflammation caused by COPD itself. Early and timely broad-spectrum anti-inflammatory treatment may have certain clinical significance for the prevention and treatment of comorbidity with osteoporosis.
Subject(s)
Emphysema , Pulmonary Disease, Chronic Obstructive , Pulmonary Emphysema , Bone Density , Humans , Inflammation/diagnostic imaging , Pulmonary Disease, Chronic Obstructive/complications , Pulmonary Disease, Chronic Obstructive/diagnostic imaging , Pulmonary Emphysema/diagnostic imagingABSTRACT
Objective: To investigate the clinical characteristics, treatment and prognosis of children with acquired thrombotic thrombocytopenic purpura (TTP). Methods: The clinical manifestations, laboratory examination, treatment and prognosis of 5 children with acquired TTP hospitalized in Beijing Children's Hospital, Capital Medical University from January 2016 to July 2019 were analyzed retrospectively. Results: There were 5 children with acquired TTP including 2 males and 3 females, with the onset age of 8.9(0.8-14.5) years, while 11 children with TTP in the same period. Thrombocytopenia and microangiopathic hemolytic anemia were found in all 5 patients. Only one patient had typical pentalogy of TTP, 3 patients had nervous system symptoms and 3 patients had fever, while renal impairment was relatively rare (1 case). Laboratory examination showed severe thrombocytopenia (7(4-14) ×109/L) and low level of hemoglobin (70(58-100)g/L) in all 5 children. Blood biochemical examination showed that total bilirubin (mainly indirect bilirubin) increased in 3 patients, lactate dehydrogenase increased in 5 patients, and urea nitrogen increased in 1 patient. Bone marrow smear showed megakaryocyte did not decrease. Plasma ADAMTS13 activity was 0 in all 5 patients while ADAMTS13 inhibitor was positive in 4 patients and negative in 1 patient. All 5 children received glucocorticoid therapy, rituximab was added in the early stage of the disease, and 3 children received plasma exchange. The time of platelet recovery to normal was 19 (9-29) days. One child had TTP recurrence after 9 months of treatment. The condition was stable after being treated with glucocorticoid and rituximab again. This case was finally diagnosed as systemic lupus erythematosus after more than 3 years followed up. By December 1, 2020, the follow-up time was 24(16-57) months.The clinical symptoms of all patients disappeared and the platelet level was stable at 159(125-269) ×109/L. Conclusions: Childhood acquired TTP is relatively rare, which can occur in all age groups. The clinical manifestations are mainly thrombocytopenia and microangiopathic hemolytic anemia, the plasma ADAMTS 13 activity and inhibitor test are helpful for the diagnosis of acquired TTP. Plasma exchange and rituximab are effective treatment. This disease requires long-term follow-up.
Subject(s)
Anemia, Hemolytic , Purpura, Thrombotic Thrombocytopenic , Adolescent , Child , Female , Humans , Male , Plasma Exchange , Purpura, Thrombotic Thrombocytopenic/diagnosis , Purpura, Thrombotic Thrombocytopenic/therapy , Retrospective Studies , Rituximab/therapeutic useABSTRACT
OBJECTIVE: The purpose of this study was to investigate the expression level of microRNA-30a-3p in hepatocellular carcinoma (HCC), and to further study its relationship with HCC clinical parameters and prognosis and the underlying mechanisms. PATIENTS AND METHODS: Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to examine microRNA-30a-3p level in 44 tumor tissue specimens and paracancerous normal ones collected from HCC patients, and the interplay between microRNA-30a-3p expression and clinical indicators, as well as prognosis of HCC patients was analyzed. Meanwhile, qPCR was also used to further verify microRNA-30a-3p expression in HCC cell lines. In addition, microRNA-30a-3p overexpression and knockdown models were constructed in HCC cell lines, and the impacts of microRNA-30a-3p on HCC cell functions was evaluated by cell counting kit-8 (CCK-8), transwell and cell wound healing assays. Finally, the Luciferase reporting assay was conducted to uncover the underlying mechanism. RESULTS: In this study, qRT-PCR results showed that the expression level of microRNA-30a-3p in tumor tissues of HCC patients was markedly lower than that in adjacent ones. Compared with patients with high expression of microRNA-30a-3p, the patients with low expression of microRNA-30a-3p had a higher incidence of lymphatic or distant metastasis and a lower overall survival rate. In the Bel-7402 cell line, the proliferation, invasion, and metastasis ability of HCC cells were decreased markedly after microRNA-30a-3p overexpression, while in Hep3B cell line, knockdown of microRNA-30a-3p enhanced the cell proliferation and invasion capacity. In addition, Luciferase reporting assay demonstrated that microRNA-30a-3p could specifically bind to IGF1. Furthermore, Western Blot results also verified a reduced expression of IGF1 after overexpression of microRNA-30a-3p, and an elevated one after knockdown of microRNA-30a-3p. Finally, cell recovery experiment verified that microRNA-30a-3p and IGF1 may regulate each other and thereby together inhibit the malignant progression of HCC. CONCLUSIONS: MicroRNA-30a-3p expression is significantly decreased in HCC tumor tissue samples, which is associated with lymph node or distant metastasis rate, as well as the poor prognosis of HCC. In addition, this research suggests that microRNA-30a-3p may inhibit the malignant progression of HCC by regulating IGF1.
Subject(s)
Carcinoma, Hepatocellular/metabolism , Insulin-Like Growth Factor I/metabolism , Liver Neoplasms/metabolism , MicroRNAs/metabolism , Carcinoma, Hepatocellular/pathology , Cell Movement , Cells, Cultured , Female , Humans , Insulin-Like Growth Factor I/genetics , Liver Neoplasms/pathology , Male , MicroRNAs/genetics , Middle AgedABSTRACT
During the epidemics of COVID-19 in domestic China and recently continuing rapid spread worldwide, a bunch of studies fitted the epidemics by transmission dynamics model to nowcast and forecast the trend of epidemics of COVID-19. However, due to little known of the new virus in early stage and much uncertainty in the comprehensive strategies of prevention and control for epidemics, majority of models, not surprisingly, predict in less accuracy, although the dynamics model has its great value in better understanding of transmission. This comment discusses the principle assumptions and limitations of the dynamics model in forecasting the epidemic trend, as well as its great potential role in evaluating the efforts of prevention and control strategies.
Subject(s)
Epidemics , Models, Biological , COVID-19 , China/epidemiology , Coronavirus Infections/epidemiology , Epidemics/prevention & control , Forecasting , Humans , Pandemics , Pneumonia, Viral/epidemiology , Reproducibility of ResultsABSTRACT
Objective: To infer the start time of the resurgent COVID-19 epidemic in Xinfadi wholesale market in Beijing in June 2020 and evaluate the effect of comprehensive prevention and control measures in this epidemic. Methods: SEIR dynamics model was used to fit daily onset infections to search the start date of this resurgent COVID-19 epidemic in Beijing. The number of cumulative infections from June 12 to July 1 in Beijing were fitted considering different levels of control strength. Results: The current reemerged COVID-19 epidemic in Beijing probably started between May 22 and May 28 (cumulative probability: 95%), with the highest probability on May 25 (23%). The R(0) of the current reemerged COVID-19 epidemic was 4.22 (95%CI: 2.88-7.02). Dynamic model fitting suggested that by June 11, the cumulative number of COVID-19 cases would reached 99 (95%CI: 77-121), which was in line with the actual situation, and without control, by July 1, the cumulative number of COVID-19 cases would reach 65 090 (95%CI: 39 068-105 037). Since June 12, comprehensive prevention and control measures have been implemented in Beijing, as of July 1, compared with uncontrolled situation, the number of infections had been reduced by 99%, similar to the fitting result of a 95% reduction of the transmission rate. The sensitivity analysis showed consistent results. Conclusions: For the emergent outbreak of COVID-19, the dynamics model can be used to infer the start time of the transmission and help tracing the source of epidemic. The comprehensive prevention and control measures taken in Beijing have quickly blocked over 95% of the transmission routes and reduced 99% of the infections, containing the sudden epidemic timely and effectively, which have value in guiding the prevention and control of the epidemic in the future.
Subject(s)
COVID-19 , Beijing , Humans , Models, Statistical , SARS-CoV-2ABSTRACT
Objectives: The COVID-19 epidemic has swept all over the world. Estimates of its case fatality rate were influenced by the existing confirmed cases and the time distribution of onset to death, and the conclusions were still unclear. This study was aimed to estimate the age-specific case fatality rate of COVID-19. Methods: Data on COVID-19 epidemic were collected from the National Health Commission and China CDC. The Gamma distribution was used to fit the time from onset to death. The Markov Chain Monte Carlo simulation was used to estimate age-specific case fatality rate. Results: The median time from onset to death of COVID-19 was M=13.77 (P(25)-P(75): 9.03-21.02) d. The overall case fatality rate of COVID-19 was 4.1% (95%CI: 3.7%-4.4%) and the age-specific case fatality rate were 0.1%, 0.4%, 0.4%, 0.4%,0.8%, 2.3%, 6.4%, 14.0 and 25.8% for 0-, 10-, 20-, 30-, 40-, 50-, 60-, 70- and ≥80 years group, respectively. Conclusions: The Markov Chain Monte Carlo simulation method adjusting censored is suitable for case fatality rate estimation during the epidemic of a new infectious disease. Early identification of the COVID-19 case fatality rate is helpful to the prevention and control of the epidemic.
Subject(s)
COVID-19 , China , Humans , Markov Chains , Monte Carlo Method , Pandemics , SARS-CoV-2ABSTRACT
Objective: To assess the risk of COVID-19 foreign imports cases to China. Methods: We collected epidemic data (cumulative daily confirmed cases in each country, cumulative confirmed imported cases), demographic data (population density, population) and information on potential source groups of tourists (the daily estimated number of overseas Chinese, overseas Chinese students, overseas workers, foreign students coming to China and flight passengers) and the global health security index (GHS) to assess and predict risk of imported cases for recent (February 1(st) to April 25(th)) and future (after April 26(th)). Results: Strong positive correlation was found among variables including the number of imported cases, cumulative confirmed cases, attack rate, number of overseas Chinese, number of overseas Chinese students, number of foreign students coming to China, number of flight passengers and GHS. In the recent risk analysis, imported cases of Russian were the highest, followed by United Kingdom, United States, France and Spain. In the future risk prediction, 44 countries including United States and Singapore are evaluated as potential high-risk countries in the future through the attack rate index of each country and the estimated average number of daily passengers. Conclusion: The risk assessment of COVID-19 imported cases can be used to identify high-risk areas in recent and future, and might be helpful to strengthen the prevention and control of the epidemic and ultimately overcome the epidemic.
Subject(s)
COVID-19 , China , Humans , Pandemics , Risk Assessment , SARS-CoV-2Subject(s)
Clinical Trials as Topic/standards , Coronavirus Infections , Pandemics , Pneumonia, Viral , Betacoronavirus , COVID-19 , Humans , SARS-CoV-2ABSTRACT
OBJECTIVE: To investigate the role of the transcription factor Zinc finger 703 (ZNF703) in influencing the progression of glioma by regulating linc-UBC1 level. MATERIALS AND METHODS: Linc-UBC1 level in glioma with different staging and tumor sizes was determined. The potential influences of linc-UBC1 on viability, cell cycle progression, and invasiveness of glioma cells were evaluated. Through RNA binding protein immunoprecipitation (RIP) assay and Dual-Luciferase reporter gene assay, the interaction between ZNF703 and linc-UBC1 was assessed. The rescue experiments were conducted to identify the role of ZNF703 in regulating cellular performances of glioma by interacting with linc-UBC1. RESULTS: Linc-UBC1 was highly expressed in glioma. Its level was higher in glioma with larger tumor size or advanced staging. The knockdown of linc-UBC1 reduced viability, arrested cell cycle in the G0/G1 phase, and attenuated invasiveness of U87 and LN229 cells. The presence of the binding sites was observed in the promoter regions of ZNF703 and linc-UBC1. The overexpression of ZNF703 could alleviate the inhibited proliferative and invasive potentials in U87 and LN229 cells with the linc-UBC1 knockdown. CONCLUSIONS: The transcription factor ZNF703 promotes the proliferative and invasive potentials in glioma cells by regulating the transcriptional activity of linc-UBC1.
Subject(s)
Carrier Proteins/metabolism , Glioma/metabolism , RNA, Long Noncoding/metabolism , Carrier Proteins/genetics , Cells, Cultured , Glioma/pathology , Humans , RNA, Long Noncoding/genetics , Up-RegulationABSTRACT
Objective: To evaluate the current status of the prevention and control of coronavirus disease (COVID-19) outbreak in China, establish a predictive model to evaluate the effects of the current prevention and control strategies, and provide scientific information for decision-making departments. Methods: Based on the epidemic data of COVID-19 openly accessed from national health authorities, we estimated the dynamic basic reproduction number R(0)(t) to evaluate the effects of the current COVID-19 prevention and control strategies in all the provinces (municipalities and autonomous regions) as well as in Wuhan and the changes in infectivity of COVID-19 over time. Results: For the stability of the results, 24 provinces (municipality) with more than 100 confirmed COVID-19 cases were included in the analysis. At the beginning of the outbreak, the R(0)(t) showed unstable trend with big variances. As the strengthening of the prevention and control strategies, R(0)(t) began to show a downward trend in late January, and became stable in February. By the time of data analysis, 18 provinces (municipality) (75%) had the R(0)(t)s less than 1. The results could be used for the decision making to free population floating conditionally. Conclusions: Dynamic R(0)(t) is useful in the evaluation of the change in infectivity of COVID-19, the prevention and control strategies for the COVID-19 outbreak have shown preliminary effects, if continues, it is expected to control the COVID-19 outbreak in China in near future.
Subject(s)
Basic Reproduction Number , Coronavirus Infections/epidemiology , Coronavirus Infections/prevention & control , Pandemics/prevention & control , Pneumonia, Viral/epidemiology , Pneumonia, Viral/prevention & control , Betacoronavirus , COVID-19 , China/epidemiology , Humans , SARS-CoV-2ABSTRACT
Objectives: Fitting and forecasting the trend of COVID-19 epidemics. Methods: Based on SEIR dynamic model, considering the COVID-19 transmission mechanism, infection spectrum and prevention and control procedures, we developed SEIR(+CAQ) dynamic model to fit the frequencies of laboratory confirmed cases obtained from the government official websites. The data from January 20, 2020 to February 7, 2020 were used to fit the model, while the left data between February 8-12 were used to evaluate the quality of forecasting. Results: According to the cumulative number of confirmed cases between January 29 to February 7, the fitting bias of SEIR(+CAQ) model for overall China (except for cases of Hubei province), Hubei province (except for cases of Wuhan city) and Wuhan city was less than 5%. For the data of subsequent 5 days between February 8 to 12, which were not included in the model fitting, the prediction biases were less than 10%. Regardless of the cases diagnosed by clinical examines, the numbers of daily emerging cases of China (Hubei province not included), Hubei Province (Wuhan city not included) and Wuhan city reached the peak in the early February. Under the current strength of prevention and control, the total number of laboratory-confirmed cases in overall China will reach 80 417 till February 29, 2020, respectively. Conclusions: The proposed SEIR(+CAQ) dynamic model fits and forecasts the trend of novel coronavirus pneumonia well and provides evidence for decision making.
Subject(s)
Coronavirus Infections/epidemiology , Coronavirus Infections/prevention & control , Forecasting , Models, Statistical , Pandemics/prevention & control , Pneumonia, Viral/epidemiology , Pneumonia, Viral/prevention & control , Betacoronavirus , COVID-19 , China/epidemiology , Humans , SARS-CoV-2ABSTRACT
Observational study of therapy efficacy comparison has been widely conducted to provide the additional efficacy evidence to support randomized control study. Statistical adjustment for unmeasured confounders is a major challenge in observational study of therapy efficacy comparison. This paper summarizes and evaluates the relative statistical methods. Currently, the most commonly used methods include instrumental variable, difference-in-differences (DiD) model and prior event rate ratio (PERR) adjustment. The instrumental variable method skill fully escapes unmeasured confounders through model structure, but it is not easy to obtain satisfied instrumental variables. Both PERR and DiD require the data prior to exposure which are not always collected in observational studies. Unmeasured confounders could result in new requirements and pose new challenges for statistical methods, which needs further study and improvement.
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Biometry , Comparative Effectiveness Research , Models, Statistical , Observational Studies as Topic , Bias , Confounding Factors, Epidemiologic , Humans , Propensity Score , Research DesignABSTRACT
Observational comparative effectiveness studies have been widely conducted to provide evidence on additional effectiveness and to support randomized controlled findings in research. Although this type of study becomes more important over time, challenges related to the common biases which stemmed from confounders, are difficult to control. This manuscript summarizes some statistical methods used on adjusting measured confounders that often noticed in research, regarding the observational comparative effectiveness. Useful traditional methods would include stratified analysis, paired analysis, covariate model and multivariable model, etc.. Unconventional adjustment approaches such as propensity score and disease risk score methods may also be used in studies, for matching, stratification and adjustment. A good study design should be able to control confounders. The limitations of all the post hoc statistical adjustment methods should also be fully understood before being appropriately applied in practical events.
Subject(s)
Confounding Factors, Epidemiologic , Models, Statistical , Observational Studies as Topic , Research Design , Bias , Propensity ScoreABSTRACT
N^(6)-methyladenosine (m^(6)A) has been identified as a conserved epitranscriptomic modification of eukaryotic mRNAs, and plays important biological roles in the regulation of cellular metabolic processes. However, its role in myogenic differentiation is unclear. Here, we altered the m^(6)A RNA methylation level by overexpression of METTL3, and explored the effect of m^(6)A RNA methylation on myogenic differentiation of murine myoblasts in vitro. The m6A RNA methylation level is regulated by exogenous methylation inhibitor cycloleucine (Cyc) and methyl donor betaine (Bet). Therefore, chemical reagents of Cyc and Bet were used to test the regulatory effect of m^(6)A RNA methylation on myogenic differentiation. Results showed that METTL3 and Bet positively regulated the m^(6)A RNA methylation levels, and Cyc negatively regulated m^(6)A RNA methylation levels. In addition, m^(6)A methylation positively regulated myogenic differentiation in murine myoblasts. These findings provide insight in the mechanisms underlying the effect of m^(6)A RNA methylation on myogenesis.
Subject(s)
Cell Differentiation , Methylation , Methyltransferases/metabolism , Muscle Development , Myoblasts/cytology , Myoblasts/metabolism , Animals , MiceABSTRACT
Mendelian randomization (MR) approach follows the Mendel's law of inheritance, which is called "Parental alleles randomly assigned to the offspring", and refers to use genetic variants as an instrumental variable to develop causal inference between the exposure factor and the outcome from observational study. In recent years, with the rapid development of genome-wide association study (GWAS) and various omics data,the disclosure of a large number of aggregated data provides an opportunity for the wide application of MR approach in causal inference. We introduce three methods widely used in MR and then apply them to explore causal relationship between blood metabolites and depressive. The advantages and disadvantages of three methods in causal inference are compared in order to provide reference for the application of MR in observational studies.
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Causality , Genome-Wide Association Study , Mendelian Randomization Analysis , Observational Studies as Topic , Alleles , Random Allocation , Research DesignABSTRACT
Statistical P value and its threshold have been controversial worldwide for a while. Recent heated debate was triggered by two practical issues: unexplainable high false positive rate in biomedical research, and global misunderstood of "statistical significance" in scientific community. Thus, part of scientists suggests applying more stringent significance level (from 0.05 to 0.005), or even giving up the use of significance level. We believe that they are throwing the baby out with the bath water. These suggestions will not contribute to any improvement of this unfavorable situation but will lead the scientific decision-making to a more difficult and subjective corner. Scientists should use statistical P value and threshold only if they correctly understand the soul of statistics-uncertainty. Statistical significance is neither sole nor dominant criterion to measure the scientific value, but an honest assistant. Scientific decision-making should initiate from the scientific experimental design, followed by rigorous implementation and transparent analysis, and synthesize a variety of information to reach a tenable conclusion.
Subject(s)
Biomedical Research/methods , Research Design/statistics & numerical data , Statistics as Topic , HumansABSTRACT
Objective: To examine the association between the frequencies of bowel movement (BMF) and the risk of colorectal cancer (CRC). Methods: In this study, 510 134 participants from the China Kadoorie Biobank (CKB) were included, after excluding those who reported as having been diagnosed with cancer at the baseline survey. The baseline survey was conducted from June 2004 to July 2008. The present study included data from baseline and follow-up until December 31, 2016. We used the Cox proportional hazards regression models to estimate the HR and the 95%CI of incident CRC with BMF. Results: During an average follow-up period of 9.9 years, 3 056 participants were documented as having developed colorectal cancer. In the site-specific analysis, 1 548 colon cancer and 1 475 rectal cancer were included. Compared with participants who had bowel movements on the daily base, the multivariable-adjusted HR (95%CI) for those who had more than once of BMF were 1.24 (1.12-1.39) for CRC, 1.12 (0.95-1.31) for colon cancer, and 1.37 (1.18-1.59) for rectal cancer. We further examined the association between BMF and CRC, according to the stages of follow-up, the corresponding HR (95%CI) for CRC, colon and rectal cancer were 1.59 (1.36-1.86), 1.43 (1.14- 1.80), and 1.76 (1.41-2.19) for the first five years, while such associations became statistically insignificant in the subsequent follow-up (P for all interactions were <0.05), as time went on. As for CRC, colon or rectal cancers among participants who had lower bowel movements, the risks were not significantly different from those who had bowel movements everyday. Conclusions: Participants who had BMF more than once a day, appeared an increased risk of CRC in the subsequent five years. Since abnormal increase of bowel movements is easily recognizable, programs should be set up on health self- management and early screening for CRC.