Un acercamiento a las variables y su escala de clasificación, a través de la "edad" como variable de estudio

La operacionalización de las variables constituye una acción investigativa de gran importancia metodológica. En este artículo se repasan, someramente, aspectos teóricos acerca de las variables de estudio, con el propósito de fundamentar la mayor utilidad y conveniencia de declarar, en el proyecto de investigación, el tipo de escala que será empleada para la agrupación de los datos provenientes de las unidades de análisis, en lugar del tipo de variable, como suele hacerse. Esta idea adquiere un evidente sentido práctico cuando se trabaja con variables cuantitativas.

The variables' operationalization constitutes a research action of great methodological importance. This article briefly reviews theoretical aspects about the study variables, to substantiate the greatest usefulness and convenience of declaring, in the research project, the type of scale that will be used to group the data coming from of the units of analysis, instead of the type of variable, as is usually done. This idea takes on an obvious practical meaning when working with quantitative variables.

Construction and self-activation detection of yeast two-hybrid bait plasmid of human programmed cell death ligand 1 immunoglobulin variable region domain gene / 中国生物制品学杂志

@#Objective To construct a yeast two-hybrid recombinant bait plasmid of human programmed cell death ligand 1(PD-L1)immunoglobulin variable region(IgV)domain gene,detect its expression in yeast and detect the cytotoxicity and self-activation of PD-L1 IgV protein as well as the interaction between PD-L1 IgV and human thioredoxin(hTrx).Methods Human PD-L1 was analyzed by bioinformatics method,and primers were designed to amplify PD-L1 IgV domain based on the coding region of PD-L1 gene registered in NCBI GenBank database. PCR amplification was carried out with pENTERPD-L1 plasmid as template,and then cloned into yeast two-hybrid bait vector pGBKT7. The recombinant bait plasmid and pGBKT7 empty vector were transformed into Y2HGold yeast cells respectively,and the PD-L1 IgV gene and its expression were detected by PCR and Western blot;Meanwhile,the protein toxicity and self-activation of PD-L1 IgV were detected,and the interaction between PD-L1 IgV and hTrx was detected by drip plate method.Results The bioinformatics analysis results of PD-L1 were consistent with related reports. The recombinant bait plasmid pGBKT7-PD-L1 IgV was correctly constructed,and Y2HGold positive clone was obtained,in which PD-L1 IgV was stably expressed. The empty vector pGBKT7 and recombinant bait plasmid pGBKT7-PD-L1 IgV grew well on SD/-Trp and SD/-Trp/X-α-Gal plates with the same colony size and number and white colony,but they did not grow on SD/-Trp/X-α-Gal/AbA plates,which indicated that PD-L1 IgV protein had no toxicity and no self-activation effect on yeast. The results of drip plates test showed that all experimental groups grew well on SD/-Trp/-Leu plate,while only positive control group grew on SD/-Trp/-Leu/X-α-Gal/AbA plate and showed blue color,which indicated that bait protein PD-L1 IgV and hTrx did not self-activate,and there was no interaction between them.Conclusion Recombinant human PD-L1 IgV bait plasmid was successfully constructed. PD-L1 IgV protein showed no toxicity and self-activation effect on yeast cells,and there was no interaction between PD-L1 IgV and hTrx. Subsequently,hTrx can be used to construct a peptide aptamer library,from which peptide aptamers that specifically bind to PD-L1 IgV can be screened.

Analysis of factors affecting stability of high concentration VHH-Fc fusion protein / 中国生物制品学杂志

@#Objective To explore the factors affecting the stability of high concentration variable domain of heavy-chain antibody-Fc(VHH-Fc) fusion protein.Methods Three groups of forced degradation experiments,shaking,light and 40℃ high temperature were set up.Differential scanning fluorimetry,dynamic light scattering(DLS) and ultra performance liquid chromatography-mass spectrometry(UPLC-MS) were used to detect the effects of the three forced degradation conditions on the conformational stability,colloidal stability,average hydrodynamic diameter and post-translational modifications of high concentration VHH-Fc fusion protein.Results Under the light condition,the onset temperature of unfolding(T_(onset)),melting temperature(T_m) and aggregation onset temperature(T_(agg)) of high concentration VHH-Fc fusion protein decreased the most,and the oxidation ratio of Met160 and Met266 increased significantly.Under the condition of shaking,the variation of the diffusion interaction parameter(k_D) and the average hydrodynamic diameter was the largest.Conclusion Light can significantly reduce the conformational stability of high concentration VHH-Fc fusion protein and induce methionine oxidation.Shaking has the most significant effect on its colloidal stability and promotes aggregation

The application of low-dose test method combined with variable helical pitch technology in CT angiography of lower extremity arteries / 实用放射学杂志

Objective To evaluate the application efficacy of low-dose test method combined with variable helical pitch(VHP)technology in computed tomography angiography(CTA)of lower extremity arteries.Methods Eighty patients with CTA imaging of bilateral lower extremity arteries were selected and divided into group A and group B on average.VHP technology was used in group A,and conventional fixed pitch scanning was used in group B.The objective and subjective image quality of the two groups were compared,and the radiation dose and contrast agent dosage of the two groups were recorded and compared.Results The subjective image quality evaluation of group A was significantly better than that of group B,and the difference was statistically significant(Kappa test,P<0.05).In the objective image quality evaluation,the CT value and signal-to-noise ratio(SNR)value of the common iliac artery,popliteal artery and anterior tibial artery in group A were higher than those in group B at the same level,and the differences were statistically significant(P<0.05);The effective dose(ED)value in group A was(6.74±1.20)mSv,and that in group B was(7.93±1.78)mSv(P<0.05).The dosage of contrast agent in group A was significantly lower than that in group B[(73.97±12.15)mL in group A,(82.50±2.61)mL in group B](P<0.05).Conclusion Low-dose test method combined with VHP technology not only can reduce the radiation dose and contrast agent dosage,but also can effectively improve the success rate and image quality of lower extremity arteries examination,which is worthy of clinical application.

Mendelian randomization study on the association between rheumatoid arthritis and osteoporosis and bone mineral density / 中国组织工程研究

BACKGROUND:Many clinical research observations have indicated a close association between rheumatoid arthritis and osteoporosis as well as bone mineral density(BMD).However,it remains unclear whether there is a causal genetic relationship between rheumatoid arthritis and the development of osteoporosis and alterations of BMD. OBJECTIVE:To assess the potential causal relationship between rheumatoid arthritis and osteoporosis as well as BMD using a two-sample Mendelian randomization approach,provide meaningful insights from a genetic perspective into the underlying mechanisms and offer a reference for early prevention of osteoporosis and improvement in the progression of the disease. METHODS:We conducted a study using data from publicly available genome-wide association studies databases to identify single nucleotide polymorphisms associated with rheumatoid arthritis as instrumental variables(P＜5×10-8).The main outcomes of the study included osteoporosis and BMD at five different sites,including total body BMD,lumbar spine BMD,femoral neck BMD,heel BMD,and forearm BMD.The inverse variance-weighted method was used as the primary analysis method to evaluate causal effects.Weighted median,simple median,weighted mode and MR-Egger regression were used as supplementary analyses.Causal relationships between rheumatoid arthritis and the risk of osteoporosis and BMD were assessed using odds ratios(OR)and 95%confidence intervals(CI).Heterogeneity was assessed using Cochran's Q test and horizontal pleiotropy was evaluated using MR-Egger intercept tests. RESULTS AND CONCLUSION:The inverse variance-weighted analysis demonstrated a positive association between genetically predicted rheumatoid arthritis and osteoporosis(OR=1.123,95%CI:1.077-1.171;P=4.02×10-8).Heterogeneity test(P=0.388)indicated no significant heterogeneity among the single nucleotide polymorphisms.MR-Egger intercept(P=0.571)tests did not detect horizontal pleiotropy,and sensitivity analysis showed no evidence of bias in the study results.There was no causal relationship between rheumatoid arthritis and BMD at the five different sites.The total body BMD(OR=1.000,95%CI:0.988-1.012;P=0.925),lumbar spine BMD(OR=0.999,95%CI:0.982-1.016;P=0.937),femoral neck BMD(OR=1.001,95%CI:0.986-1.016;P=0.866),heel BMD(OR=0.996,95%CI:0.989-1.004;P=0.419),and forearm BMD(OR=1.063,95%CI:0.970-1.031;P=0.996)indicated no significant association.MR-Egger intercept analysis did not detect potential horizontal pleiotropy(total body BMD:P=0.253;lumbar spine BMD:P=0.638;femoral neck BMD:P=0.553;heel BMD:P=0.444;forearm BMD:P=0.079).Rheumatoid arthritis may contribute to the development of osteoporosis through the interaction between chronic inflammation and bone formation,resorption,and absorption.Additionally,the use of glucocorticoids and the presence of autoantibodies(such as anti-citrullinated protein antibody)in patients with rheumatoid arthritis showed associations with osteoporosis.Future research should focus on monitoring systemic inflammatory markers,standardized use of glucocorticoids,and regular screening for osteoporosis risk in patients with rheumatoid arthritis.

Causal association of micronutrients with osteonecrosis:evidence from a bidirectional Mendelian randomization trial / 中国组织工程研究

BACKGROUND:Osteonecrosis is a common refractory disease in clinical practice,and observational studies have suggested that micronutrients may have a prognostic role in osteonecrosis.However,the specific causal association between micronutrients and osteonecrosis is not known. OBJECTIVE:To explore the causal association between micronutrients and osteonecrosis by Mendelian randomization using summary data from a large population-based genome-wide association study(GWAS)for clinical diagnosis and treatment. METHODS:The required exposure and outcome data(calcium,magnesium,iron,vitamin E,carotenoids,retinol&osteonecrosis)were extracted from the IEU OpenGWAS database,GWAS catalog database,and FinnGen database.Data were analyzed by bidirectional Mendelian randomization with inverse-variance weighted as the primary study method,and weighted median method,simple mode method,weighted mode method,and MR-Egger regression to complement the results.The reliability of the data was then verified through sensitivity analyses. RESULTS AND CONCLUSION:(1)The results found a positive correlation between serum iron concentration and osteonecrosis,while no correlation was found for other micronutrients.There was no reverse causality in all the data.(2)The results of sensitivity analysis showed a robust causality.(3)By Mendelian randomization method,this study provided evidence of causality between serum iron concentration and osteonecrosis,and understanding the causality of micronutrient elements on osteonecrosis can help in the clinical diagnosis and treatment of osteonecrosis,which is of great clinical significance.

Causal relationship between periodontitis and asthma: a two-sample Mendelian randomization study / 口腔疾病防治

Objective@#To explore the bidirectional causal relationships between periodontitis and asthma using the two-sample Mendelian randomization (MR) method to provide a basis for exploring the etiology and formulating preventive and therapeutic measures of periodontitis and asthma.@*Methods@#We performed two-sample bidirectional Mendelian randomization analysis using publicly released European genome-wide association studies (GWAS) statistics for periodontitis (n = 34 615) and asthma (n = 408 422). The inverse variance weighted (IVW) method was employed as the main approach to estimate the bidirectional causal relationships between periodontitis and asthma. In addition, weighted median (WM), MR-Egger regression, maximum likelihood, and Mendelian randomization robust adjusted profile score (MR-RAPS) were used as supplementary analyses. Sensitivity analyses were conducted using Cochran's Q test, Mendelian randomization pleiotropy residual sum and outlier (MR-PRESSO), and leave-one-out analysis.@*Results@#A total of 12 and 43 single-nucleotide polymorphisms (SNPs) were included as instrumental variables for periodontitis and asthma, respectively. The results of IVW, WM, MR-Egger regression, maximum likelihood, and MR-RAPS showed that periodontitis was not causally related to the risk of asthma (IVW: OR: 1.003, 95% CI: 0.973-1.035, P = 0.828, WM: OR: 0.990, 95% CI: 0.951-1.031, P = 0.641; MR-Egger regression: OR: 0.988, 95% CI: 0.960-1.028, P = 0.573; maximum likelihood: OR: 1.003, 95% CI: 0.972-1.035, P = 0.834; MR-RAPS: OR: 1.002, 95% CI: 0.970-1.036, P = 0.890) among the European population, and no causal effect of asthma on periodontitis was found (IVW: OR: 1.021, 95% CI: 0.938-1.111, P = 0.633, WM: OR: 1.011, 95% CI: 0.894-1.142, P = 0.866; MR-Egger regression: OR: 1.042, 95% CI: 0.824-1.319, P = 0.731; maximum likelihood: OR: 1.021, 95% CI: 0.938-1.112, P = 0.631; MR-RAPS: OR: 1.017, 95% CI: 0.931-1.110, P = 0.713) among the European population. Cochran's Q test showed no heterogeneity among the included instrumental variables, MR-PRESSO test found no horizontal pleiotropy, and the leave-one-out method did not identify outlier SNPs.@*Conclusion@#The results of this study, based on European genetic data, do not support a bidirectional causal association between periodontitis and asthma in the European population.

Applications and advancements of instrumental variable approach in causal inference in environmental epidemiology / 环境与职业医学

In environmental epidemiological research, extensive non-random environmental exposures and complex confounding biases pose significant challenges when attempting causal inference. In recent years, the introduction of causal inference methods into observational studies has provided a broader range of statistical tools for causal inference research in environmental epidemiology. The instrumental variable (IV) approach, as a causal inference technique for effectively controlling unmeasured confounding factors, has gradually found application in the field of environmental epidemiological research. This article reviewed the basic principles of IV and summarized the current research progress and limitations of applying IV for causal inference in environmental epidemiology. IV application in the field of environmental epidemiology is still in the initial stage. Rational use of IV and effective integration with other causal inference methods will become the focus of the development of causal inference in environmental epidemiology. The aim of this paper is to provide a methodological reference and basis for future studies involving causal inference to target population health effects of environmental exposures in China.

Analysis of factors affecting stability of high concentration VHH-Fc fusion protein / 中国生物制品学杂志

@#Objective To explore the factors affecting the stability of high concentration variable domain of heavy-chain antibody-Fc(VHH-Fc) fusion protein.Methods Three groups of forced degradation experiments,shaking,light and 40℃ high temperature were set up.Differential scanning fluorimetry,dynamic light scattering(DLS) and ultra performance liquid chromatography-mass spectrometry(UPLC-MS) were used to detect the effects of the three forced degradation conditions on the conformational stability,colloidal stability,average hydrodynamic diameter and post-translational modifications of high concentration VHH-Fc fusion protein.Results Under the light condition,the onset temperature of unfolding(T_(onset)),melting temperature(T_m) and aggregation onset temperature(T_(agg)) of high concentration VHH-Fc fusion protein decreased the most,and the oxidation ratio of Met160 and Met266 increased significantly.Under the condition of shaking,the variation of the diffusion interaction parameter(k_D) and the average hydrodynamic diameter was the largest.Conclusion Light can significantly reduce the conformational stability of high concentration VHH-Fc fusion protein and induce methionine oxidation.Shaking has the most significant effect on its colloidal stability and promotes aggregation.

Prokaryotic expression of variable region protein of adeno-associated virus 9 capsid and preparation of polyclonal antibody / 中国生物制品学杂志

@#Objective To express and purify the protein of variable region of adeno-associated virus 9(AAV9) capsid in prokaryotic cells,and prepare rabbit polyclonal antibody against it.Methods DNA sequence encoding variable region of AAV9 capsid protein was designed,synthesized and inserted into prokaryotic expression vector pET-30a. The obtained plasmid pET-30a-AAV-VR was transformed to E.coli BL21(DE3),induced by IPTG to express the multivalent antigenic peptide and purified by Ni-NTA resin under denaturation conditions. Male Japanese large-eared white rabbits were immunized with the AAV9 variable region protein after dialysis and renaturation to prepare polyclonal antibody,which was determined for the antibody potency by indirect ELISA,and for the specificity by Western blot and cellular immunofluorescence.Results The recombinant prokaryotic expression plasmid pET-30a-AAV-VR expressing the variable region of AAV9 capsid was constructed correctly as identified by XhoⅠ and BglⅡ digestion. The expressed protein was recognized by His tag antibody after purification with a relative molecular mass of about 20 000. The potency of rabbit polyclonal antibody was 1∶10 240 000,which specifically recognize AAV9 capsid protein.Conclusion The capsid variable region protein of AAV9 was successfully expressed and rabbit polyclonal antibody with high potency was prepared,which laid a foundation of the subsequent development of AAV vector and the research of AAV biological function.

Modelos de variables latentes en patrones de alimentación y actividad física en niños/adolescentes: una revisión sistemática / Models of latent variables used for eating and physical activity patterns in children/ adolescents: a systematic review

Introducción. Debido a la poca evidencia sobre el modelamiento de los patrones de alimentación y actividad física (AF), basado en variables latentes, el presente estudio de revisión pretende describir las técnicas estadísticas aplicadas para modelar estos patrones en niños y adolescentes y valorar su calidad metodológica. Materiales y métodos. La búsqueda se realizó en bases de datos electrónicas (Science Direct, PubMed, SCOPUS, Web of science y Cochrane) con las palabras "diet", 'physical activity', children y 'latent variable'. Se incluyeron artículos que utilizaron modelos estadísticos basados en variables latentes para analizar patrones de alimentación y AF en niños y adolescentes sanos, publicados entre 2014­2019, en inglés o español. Resultados. Entre los 27 artículos seleccionados, el Modelo de Ecuaciones Estructurales (MEE) fue el más utilizado (77,78%); seguido del Modelo de Perfil Latente (7,41%), mientras, el restante, 14,81% aplican el Modelo del Factor Común, Modelo Ecológico y el Modelo de Regresión Logística Multinivel. El MEE fue aplicado a 12 de los 16 artículos con enfoque de AF, y en 7 de los 9 artículos con enfoque de Alimentación. El 48,15% de los estudios sí justificaba el uso del modelo, y el 37,04% poseen una calidad "Excelente" (cumplen el 85% o más de los ítems de STROBE). Conclusiones. El MEE fue el más utilizado para abstraer los patrones de AF y alimentación en niños y adolescentes, sin embargo, solo la mitad de los artículos justifica su pertinencia. Las guías de reporte de estudios deberían evaluar la calidad metodológica de los modelos estadísticos aplicados(AU)

Introduction. Due to the limited evidence on the modeling of eating and physical activity (PA) patterns based on latent variables, the present review study aims to describe the statistical techniques applied to model these patterns in children and adolescents and to assess their methodological quality. Materials and methods. The search was performed in electronic databases (Science Direct, PubMed, SCOPUS, Web of science and Cochrane) with the words 'diet', 'physical activity', children and 'latent variable'. We included articles that used statistical models based on latent variables to analyze diet and PA patterns in healthy children and adolescents, published between 2014-2019, in English or Spanish. Results. Among the 27 selected articles, the Structural Equation Model (SEM) was the most used (77.78%); followed by the Latent Profile Model (7.41%), while, the remaining 14.81% applied the Common Factor Model, Ecological Model and Multilevel Logistic Regression Model. The SEM was applied to 12 of the 16 articles with PA approach, and in 7 of the 9 articles with eating approach. The 48.15% of studies did justify the use of the model, and 37.04% were classified as "Excellent" quality (meet 85% or more of the STROBE items). Conclusions. The SEM was the most commonly used to model the PA and eating patterns in children and adolescents, however, only half of the articles justify their relevance. Study reporting guidelines should evaluate the methodological quality of the statistical models applied(AU)

Myasthenia gravis in the complex scenario of LRBA-related immune dysregulation / Miastenia gravis no cenário clínico complexo das imunodesregulações relacionadas ao gene LRBA

Autoimmune diseases have been progressively recognized as a potential complication of primary immunodeficiency, especially for some genetic subtypes of common variable immunodeficiency. Although often associated with other autoimmune disorders, autoimmune myasthenia gravis is occasionally identified as a neuromuscular complication of primary immunodeficiency. We report the case of a Brazilian woman with common variable immunodeficiency-8 due to an LRBA variant, in which myasthenia gravis was identified in association with anti-acetylcholine receptor antibody. Marked clinical improvement occurred after intravenous immunoglobulin therapy.

Doenças autoimunes foram progressivamente reconhecidas como complicações potenciais das imunodeficiências primárias, especialmente para alguns subtipos genéticos das imunodeficiências comuns variáveis. Embora se associe comumente a outras doenças autoimunes, a Miastenia gravis autoimune adquirida foi raramente associada como complicação neuromuscular de imunodeficiências primárias. É descrito neste artigo o caso de paciente brasileira do sexo feminino com diagnóstico de Imunodeficiência Comum Variável tipo 8 por variante no gene LRBA, na qual foi identificada Miastenia gravis em associação a anticorpos antirreceptor de acetilcolina. Ela evoluiu com marcante melhora clínica após a introdução de terapêutica com imunoglobulina endovenosa.

Screening and identification of single-chain fragment variable against the receptor-binding domain of spike protein of SARS-CoV-2 / 中国生物制品学杂志

@#Objective To construct a single-chain fragment variable(scFv)phage display library against receptor-binding domain(RBD)of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)spike protein(S)to screen specific scFv and identify the function.Methods m RNA was extracted from spleen cells of mice immunized with RBD protein and reversely transcribed into c DNA,with which as template,genes of the hight chain fragment of variable(VH)and light chain fragment of variable(VL)of scFv were amplified and then assembled into scFv gene fragment through splicing overlap extension PCR(SOE-PCR).The scFv gene fragment was inserted to phage vector to construct scFv phage display library.After four rounds of biopanning,the scFv gene with strong binding ability to RBD was screened and expressed recombinantly,purified and identified for biological activity.Results The constructed scFv phage library showed a titer of 6.0×10(11)pfu/m L.After four rounds of biopanning,four scFv strains with strong binding to RBD were selected,namely scFv11,scFv12,scFv25and scFv28.scFv was mainly expressed in the form of inclusion body with a relative molecular mass of about 27 000,a concentration of 2.4 mg/m L and a purity of about 90%,which bound specifically to mouse monoclonal antibody against His labeled by HRP after purification.All four scFv strains bound specifically to RBD recombinant protein,among which the other 3 scFv strains bound to the S protein of wild type and multiple mutant strains except scFv28.All four strains showed dose-dependent interaction with RBD,with affinity dynamic fitting dissociation constants(K_Ds)8.9,5.92,10.67and 2.36 nmol/L,and steady-state fitting dissociation constants(K_Ds)of 5.3,6.5,8.7 and 5.8 nmol/L,respectively.scFv11,scFv12 and scFv25 simultaneously identified three independent RBD polypeptides,including RBD2(S(11)pfu/m L.After four rounds of biopanning,four scFv strains with strong binding to RBD were selected,namely scFv11,scFv12,scFv25and scFv28.scFv was mainly expressed in the form of inclusion body with a relative molecular mass of about 27 000,a concentration of 2.4 mg/m L and a purity of about 90%,which bound specifically to mouse monoclonal antibody against His labeled by HRP after purification.All four scFv strains bound specifically to RBD recombinant protein,among which the other 3 scFv strains bound to the S protein of wild type and multiple mutant strains except scFv28.All four strains showed dose-dependent interaction with RBD,with affinity dynamic fitting dissociation constants(K_Ds)8.9,5.92,10.67and 2.36 nmol/L,and steady-state fitting dissociation constants(K_Ds)of 5.3,6.5,8.7 and 5.8 nmol/L,respectively.scFv11,scFv12 and scFv25 simultaneously identified three independent RBD polypeptides,including RBD2(S(334～353)),RBD9(S(334～353)),RBD9(S(439～458))and RBD13(S(439～458))and RBD13(S(499～518)).Homologous model of scFv constructed by online server SWISS-MODEL showed a good quality and was used for molecular docking.The interface at which scFv11 interacted with RBD only partially coincided with the interaction interface of human angiotensin converting enzyme 2(ACE2)and RBD,and the interaction interfaces of scFv12 and scFv25 with RBD were quite different from that of ACE2.Conclusion In this study,scFv specifically bound to SARS-Co V-2 RBD was screened and prepared through constructing scFv phage library against SARS-CoV-2 RBD,which provided experimental basis for further development of anti-SARS-CoV-2 drugs and detection reagents.

Infrared spectral band screening based on partial least squares is used for the quantitative analysis of mannitol-calcium chloride cocrystal / 药学学报

Mannitol-calcium chloride metal organic framework (MOF) cocrystal significantly improved the tabletability of β-mannitol and could be developed as a new tablet filler. However, mannitol monomer was found in the product during the scale-up production of the excipient, which significantly affected the functional properties of the excipient. In this study, we intend to quantify the multi-component eutectic system of mannitol-calcium chloride. In this experiment, the MOF cocrystal excipient mannitol-calcium chloride cocrystal was used as the model compound, and infrared spectrum was collected. Based on partial least squares regression (PLSR) method, the abnormal bands were removed and the spectrum was preprocessed by normalization. The quantitative correction model of mannitol-calcium chloride MOF cocrystal content in cocrystal excipients was established and compared by two different variable screening methods, genetic algorithm (GA) and competitive adaptive reweighting algorithm (CARS). Two different variable screening methods, GA method and CARS method, were used to screen out 160 and 14 variables, respectively. The mannitol-calcium chloride cocrystal model established by CARS-PLSR method had the best performance, and the average relative error (MRE) and corrected root mean square error (RMSEC) of the model were 0.008 8 and 0.892 5, respectively, the determination coefficient (R2) of the model was increased from 0.978 3 to 0.994 4. The quantitative method of eutectic system established in this study has high prediction accuracy, fast detection speed and good stability, which is of great significance for optimizing the preparation process conditions and quality control methods of such eutectic excipients.

Correlation and clinical significance of VISTA expression and cervical squamous cell carcinoma / 中华肿瘤杂志

Objective: To explore the relationship between the expression of the T-cell activation suppressor-immunoglobulin variable region (VISTA) and the development of cervical squamous cell carcinoma (CSCC), and the impact on the prognosis of CSCC patients. Methods: Cervical tissue samples from 116 CSCC, including 23 cervical intraepithelial neoplasia (CIN) grade I, 23 CIN grade Ⅱ-Ⅲ, and 23 chronic cervicitis patients, were collected from the First Hospital of Soochow University between March 2014 and April 2019. The expression of VISTA in each group was detected by immunohistochemistry (IHC). Survival data of CSCC patients were obtained by follow-up. The survival analysis was performed by Kaplan-Meier method, and survival differences between groups were compared by Log rank test. Prognostic impact factors were analyzed using a multifactorial Cox proportional hazards model. Results: The positive rate of VISTA expression in CSCC group was 32.8% (38/116), and which of grade Ⅱ-Ⅲ was 17.4% (4/23). VISTA expression results showed no positive expression patients in the cervical intraepithelial neoplasia grade I and chronic cervicitis groups. The differences between the CSCC group and other groups were statistically significant (P<0.01). In 116 CSCC patients, VISTA expression was associated with International Federation of Gynecology and Obstetrics (FIGO) stage and lymph node metastasis (P<0.01). The mean survival time of patients in the VISTA positive expression group was 30.7 months, and the 3-year survival rate was 44.7% (17/38). However, the mean survival time of the patients in the VISTA negative expression group was 49.1 months, and the 3-year survival rate was 87.2% (68/78). The Cox regression model found that VISTA expression positivity (P=0.001) and FIGO stage (P=0.047) were prognostic factors for CSCC, and patients with VISTA-positive CSCC had a 4.130-fold risk of death higher than those with VISTA-negative expression. Conclusions: The VISTA protein is highly expressed in CSCC tissues, and its expression level is closely related to the occurrence and development of CSCC. The expression of VISTA can be used as an independent predictor of CSCC prognosis and can provide a strong basis for the treatment of CSCC with immune checkpoint inhibitors.

Structural Design and Optimization of Cushioning Insole with Variable Stiffness / 医用生物力学

Objective An X-shaped cushioning insole with variable stiffness was designed to explore its effects on plantar pressure and internal stress of diabetic patients with toe amputation. Methods Based on CT images, the feet-calf finite element model of diabetic patients with toe amputation was established, and the insole was divided into different areas according to distribution characteristics of the planter pressure. The three-dimensional (3D) printed cushioning insole with an X-shaped sandwich structure was designed. The modulus of the sandwichstructure was changed by changing thickness of the sandwich structure panel. For simulation analysis, the divided area was filled with the X-shaped sandwich structure with different modulus. Results The peak plantar pressure of diabetic patients with toe amputation was in calcaneal region, and the combined insoles with 1. 2 mpanel thickness in toe area, 1. 4 mm panel thickness in metatarsal area, 2. 0 mm panel thickness in middle area and 1. 6 mm panel thickness in heel area had the best decompression effect. Compared with bare feet, the peak pressure in heel area of the insole, the peak pressure in phalangeal head area and the stress in plantar softissues were reduced by 40. 18% , 31. 7% , and 50. 44% , respectively. Conclusions The 3D printed insoles with variable stiffness can effectively reduce surface pressure and internal stress of the sole and reduce probability of the 2nd toe amputation

Research and Application Analysis of Risk Prediction Models for Prostate Cancer from a Data-driven Perspective / 医学信息学杂志

Purpose/Significance The paper retrospectively analyzes the research progress on risk prediction models for prostate cancer,and provides references for the construction of prostate cancer intelligent diagnosis and treatment system.Method/Process Through literature mining and analysis,the significance of molecular,imaging,individual,population and other omics level evaluation indexes in the diagnosis of prostate cancer is discussed,and the key characteristic variables and clinical application value of different cal-culation models are compared.Result/Conclusion The existing models have advantages of easy calculation and strong feasibility,but they also have limitations such as limited prediction accuracy and insufficient generalization ability.The integration of multi-omics data and artificial intelligence models is of great significance for medical informatics research and smart medical system construction of prostate cancer.

Empirical Study on the Relationship Between Health Investment and Economic Growth in China Using Threshold Effect Model and Instrumental Variable Method / 医药导报

Objective To study the relationship between health investment and economic growth in China.Methods An empirical study was conducted using threshold effect models and instrumental variable methods.Results Human capital investment in health sector can promote economic growth more than physical capital investment.Conclusion More human capital investment,such as the number of health personnel,should be added in the future health investment,and physical capital investment,such as the number of beds,should be controlled.The eastern region should increase health investment related to the elderly,which is more conducive to regional economic growth,while the central region should also increase health investment in physical capital such as the number of beds,while the western region should increase health investment in both aspects,which is more conducive to economic growth,because the economic development is relatively slow.

Identification of Kidney-Yang Deficiency Syndrome in Osteoporosis Patients Based on Rule Ensemble Method of Bagging Combining LASSO Regression / 中国实验方剂学杂志

ObjectiveTo investigate the identification of kidney Yang deficiency syndrome of patients with osteoporosis（OP）， and to form the clinical syndrome identification rules of traditional Chinese medicine（TCM）. MethodBasic information， etiology， clinical symptoms and other characteristics of 982 OP patients were included， and statistical tests were used to screen the variables associated with kidney Yang deficiency syndrome. Taking the decision tree as the base model， bootstrap aggregation algorithm（Bagging algorithm） was utilized to establish the classification model of kidney Yang deficiency syndrome in OP， generating numerous rules and removing redundancy. Combining least absolute shrinkage and selection operator（LASSO） regression to screen key rules and integrate them to construct an identification model， achieving the identification of kidney Yang deficiency syndrome in OP patients. ResultEighteen key identification rules were screened out， and of these， where 11 rules with regression coefficients>0 correlated positively with the kidney Yang deficiency syndrome， the rule with the highest coefficient was chilliness（present）&feverish sensation over the palm and sole（absent）. The other 7 rules with regression coefficients<0 correlated negatively with the syndrome， the rule with the lowest coefficient was reddish tongue（present）&diarrhea（absent）&deficiency of endowment（absent）. According to the regression coefficients of each key rule， variables with importance>0.2 were ranked as chilliness， reddish tongue， feverish sensation over the palm and sole， cold limbs， clear urine， diarrhea， deficiency of endowment， prolonged illness. The results of the partial dependence analysis of the identification model showed that compared to OP patients without chilliness， those with chilliness（present） had a 0.266 8 higher probability of being identified as having kidney Yang deficiency syndrome， indicating that this variable had the highest impact on identification of the syndrome. Similarly， compared to OP patients without reddish tongue， those with reddish tongue had a 0.141 9 lower probability of being identified as having kidney Yang deficiency syndrome， indicating that this variable had the highest impact on identifying non-kidney Yang deficiency syndrome. The accuracy， sensitivity， specificity and area under receiver operating characteristic curve（AUC） of the established kidney Yang deficiency syndrome identification model in the test set were 0.865 9， 0.853 7， 0.872 0 and 0.931 5， respectively. ConclusionA precise identification model of OP kidney Yang deficiency syndrome is conducted basing on the rule ensemble method of Bagging combining LASSO regression， and the screened key rules can explain the identification process of kidney Yang deficiency syndrome. In this research， according to the regression coefficients of rules， the importance and partial dependence of variables， combined with the thinking of TCM， the influence of patient characteristics on the identification of syndromes is described， so as to reveal the primary and secondary syndromes of identification and assist the clinical identification of kidney Yang deficiency syndrome.

Commentary on Medical Education after Experiencing the COVID-19 Pandemic / 医学教育

In Japan, the standards for establishing universities were revised in September 2022. Universities have accumulated considerable experience through the COVID-19 pandemic, including in distance education. In this revision, the Ministry of Education, Culture, Sports, Science, and Technology has opened the door to implementing educational methods and credit recognition that were not permitted under the current ministry ordinances, as a 'special system' (Tokurei-seido). It is necessary for universities to accumulate the results of social experiments, such as the 'special system' (Tokurei-seido), and utilize them in future revisions of the standards.　Overseas, the pandemic has spurred debates about whether medical students should be considered learners who need protection or as essential workers. In the UK, medical students graduated early and transitioned to clinical training sooner during the pandemic. This trend was in contrast to the United States, where medical students were isolated from clinical practices. The pandemic has disrupted the sequence of basic sciences, clinical sciences, and clinical clerkships. Medical students were unable to gain sufficient clinical experience during clinical clerkships. Despite the lack of study time in classrooms and clerkship rotations in clinical settings, medical students were promoted, graduated, and transitioned to clinical training. In this context, there are discussions about competency-based, time-variable (CBTV) education, which focuses on the competencies learners acquire rather than the amount of instructional time.