BACKGROUND:Streptococcus mutans is an important pathogen of dental caries,and timely detection of its levels is of great significance for early detection and treatment of dental caries. OBJECTIVE:To evaluate the effect of loop-mediated isothermal amplification(FTA-LAMP)direct extraction of Streptococcus mutans DNA. METHODS:(1)Bacterial suspensions containing ATCC standard strains(Streptococcus mutans)were prepared and inoculated into the brain-heart leachate medium.After mixed thoroughly,the mixture was then diluted in a 10-fold gradient into seven concentrations(4.2×107,4.2×106,4.2×105,4.2×104,4.2×103,4.2×102,4.2×10 CFU/mL),two parallel controls were made for each dilution level,and sterile water was used as a blank control.(2)The DNA of Streptococcus mutans was extracted using FTA Elute card,boiling method,kit extraction and lysate extraction methods separately and then amplified using LAMP technology was amplified.A specificity test was also performed to compare the differences between the four DNA extraction methods.RESULTS AND CONCLUSION:The DNA extracted by all four methods met the requirements for LAMP amplification.Specificity test results showed that only Streptococcus mutans could specifically amplify the target gene.The detection limit value of the DNA concentration was 4.2×103 CFU/mL for the lysate method,4.2×104 CFU/mL for the FTA Elute card extraction method,4.2×106 CFU/mL for the kit extraction method,and 4.2×107 CFU/mL for the boiling method.In the other aspects of the four extraction methods,the kit extraction method had the highest experimental cost,number of steps and time;the other three methods had the same number of steps,with the FTA Elute card method requiring the least amount of instruments,the boiling method having the lowest single cost,and the lysate extraction method taking the least amount of time.Only a small amount of bacteria were needed for successful extraction using both the FTA Elute card and lysate extraction methods.Compared with the FTA Elute card method,the lysate extraction method was superior in terms of time,but it had a high single cost and required more equipment.To conclude,the FTA-LAMP technology established in this study has the advantages of ease of operation,high specificity,high sensitivity,and visualization,which is expected to be a new way for efficient extraction and detection of Streptococcus mutans.

Purpose To investigate the value of intratumoral and peritumoral radiomics features based on multi-parametric MRI for preoperative prediction of lymphovascular invasion(LVI)in clinical lymph node-negative(cN0)breast cancer.Materials and Methods This retrospective study included 280 patients with pathologically confirmed breast cancer who underwent preoperative MRI at Henan Provincial People's Hospital from January 2017 to May 2021.Patients were randomly divided into a training cohort and a testing cohort.After Z-score normalization,feature selection was performed using Select K Best and least absolute shrinkage and selection operator regression.Random forest algorithms were used to construct intratumoral,peritumoral,and combined intratumoral-peritumoral radiomics models for LVI prediction.Model performance and clinical utility were evaluated using the area under the receiver operating characteristic curve(AUC),calibration curves and decision curve analysis.Results High Ki-67 expression(≥20%),axillary lymph node metastasis and positive diffusion weighted imaging(DWI)margin sign were more common in the LVI-positive group(χ2=5.959,18.316,20.554,all P<0.05).In the testing cohort,the AUC values of the dynamic contrast-enhanced(DCE)-Intra and DCE-Com models for predicting LVI status were higher than those of the DWI sequence,whereas the AUC value of the DWI-Peri model was higher than that of the DCE sequence.The DWI-DCE-Com model achieved AUCs of 0.836 and 0.818 in the training and testing cohorts,respectively,which surpassed the predictive performance of single-sequence intratumoral-peritumoral radiomics models(DWI-Com,DCE-Com).Decision curve analysis showed that the DWI-DCE-Com model provided greater net clinical benefit across a reasonable range of threshold probabilities.Conclusion Radiomics models based on multiparametric MRI features from intratumoral and peritumoral regions can effectively predict LVI status in cN0 breast cancer,offering valuable support for preoperative individualized treatment decision-making.

Purpose To investigate the value of intratumoral and peritumoral radiomics features based on multi-parametric MRI for preoperative prediction of lymphovascular invasion(LVI)in clinical lymph node-negative(cN0)breast cancer.Materials and Methods This retrospective study included 280 patients with pathologically confirmed breast cancer who underwent preoperative MRI at Henan Provincial People's Hospital from January 2017 to May 2021.Patients were randomly divided into a training cohort and a testing cohort.After Z-score normalization,feature selection was performed using Select K Best and least absolute shrinkage and selection operator regression.Random forest algorithms were used to construct intratumoral,peritumoral,and combined intratumoral-peritumoral radiomics models for LVI prediction.Model performance and clinical utility were evaluated using the area under the receiver operating characteristic curve(AUC),calibration curves and decision curve analysis.Results High Ki-67 expression(≥20%),axillary lymph node metastasis and positive diffusion weighted imaging(DWI)margin sign were more common in the LVI-positive group(χ2=5.959,18.316,20.554,all P<0.05).In the testing cohort,the AUC values of the dynamic contrast-enhanced(DCE)-Intra and DCE-Com models for predicting LVI status were higher than those of the DWI sequence,whereas the AUC value of the DWI-Peri model was higher than that of the DCE sequence.The DWI-DCE-Com model achieved AUCs of 0.836 and 0.818 in the training and testing cohorts,respectively,which surpassed the predictive performance of single-sequence intratumoral-peritumoral radiomics models(DWI-Com,DCE-Com).Decision curve analysis showed that the DWI-DCE-Com model provided greater net clinical benefit across a reasonable range of threshold probabilities.Conclusion Radiomics models based on multiparametric MRI features from intratumoral and peritumoral regions can effectively predict LVI status in cN0 breast cancer,offering valuable support for preoperative individualized treatment decision-making.

Objective:To establish a rapid,quantitative and visualized method for the rapid detection of Streptococcus mutans(S.mutans)based on loop-mediated isothermal amplification(LAMP).Methods:Nucleic acid of S.mutans was extracted for LAMP reaction,the detection experimental conditions were optimized.Finally the positive results of the experiments were quantita-tively analyzed by using the mobile-based detection equipment.Results:The system detected the samples within 23 min and showed good specificity and sensitivity with an accuracy of 1.625×10-3 ng/μL.Positive results were captured,identified and quantified u-sing a mobile application,and the quantified results showed a good linear relationship between the absolute G value and the DNA concentration,with an equation of y=3.2x+57.133(R2=0.988 2).Conclusion:Quantitative detection of S.mutans by LAMP has the characteristics of high sensitivity,high specificity,result visualization,convenience and time-saving,and can quantify bacterial DNA.It is a new method for the early detection of caries susceptibility,and can be widely used in clinic.

Objective:To establish a rapid,quantitative and visualized method for the rapid detection of Streptococcus mutans(S.mutans)based on loop-mediated isothermal amplification(LAMP).Methods:Nucleic acid of S.mutans was extracted for LAMP reaction,the detection experimental conditions were optimized.Finally the positive results of the experiments were quantita-tively analyzed by using the mobile-based detection equipment.Results:The system detected the samples within 23 min and showed good specificity and sensitivity with an accuracy of 1.625×10-3 ng/μL.Positive results were captured,identified and quantified u-sing a mobile application,and the quantified results showed a good linear relationship between the absolute G value and the DNA concentration,with an equation of y=3.2x+57.133(R2=0.988 2).Conclusion:Quantitative detection of S.mutans by LAMP has the characteristics of high sensitivity,high specificity,result visualization,convenience and time-saving,and can quantify bacterial DNA.It is a new method for the early detection of caries susceptibility,and can be widely used in clinic.

Objective:To explore the effects of applying peer-assisted learning (PAL) combined with modular teaching in physiology education, and to explore a more suitable mode for physiology teaching and learning.Methods:We selected a total of 89 undergraduate medical students of grade 2022 from a university offering physiology courses from February 28 to June 30, 2022. They were assigned using a random number table into experimental class (44 students) and control class (45 students). The experimental class adopted PAL with modular teaching, while the control class adopted the online and offline hybrid teaching method. The two classes were compared for teaching effects in terms of the completion rate of task points, final assessment scores, and questionnaire results. SPSS 19.0 was used to perform the independent samples t-test and the chi-square test. Results:The final exam scores for the objective questions of the experimental class and the control class were (43.04±3.25) and (40.24±8.64), respectively; the scores for the subjective items were (44.49±2.80) and (39.21±5.71), respectively; and the total scores were (87.53±4.24) and (79.40±12.08), respectively, all with significant differences between the two classes. There were significant differences in students' learning autonomy, micro-video preview rate, problem discussion participation rate, unit self-test participation rate, and after-class homework completion rate. The questionnaire survey showed that students in the experimental class believed that this teaching model was helpful for improving students' comprehensive qualities.Conclusions:PAL combined with modular teaching can effectively improve physiology teaching effects and students' learning autonomy and comprehensive abilities.

Objective To observe the value of intratumoral and peritumoral radiomics based on diffusion weighted imaging(DWI)for predicting histological grade of breast cancer.Methods Preoperative DWI data of 700 patients with single breast cancer diagnosed by pathology were retrospectively analyzed.The patients were divided into training set(n= 560,including 381 of grade Ⅰ+Ⅱ and 179 of grade Ⅲ)and test set(n=140,including 95 of grade Ⅰ+Ⅱ and 45 of grade Ⅲ)at the ratio of 8∶2.Intratumoral ROI(ROIintra)was manually delineated on DWI,which was automatically expanded by 3 mm and 5 mm to decline peritumoral ROI(ROIperi,including ROI3 mm and ROI5 mm),then intratumoral-peritumoral ROI(ROIintra+3 mm,ROIintra+5 mm)were obtained.The optimal radiomics features were extracted and screened,and the radiomics model(RM)for predicting the histological grade of breast cancer were constructed.Receiver operating characteristic curves were drawn,and the areas under the curve(AUC)were calculated to evaluate the predictive efficacy of each model.Calibration curve method was used to evaluate the calibration degree,while decision curve analysis(DCA)was performed to explore the clinical practicability of each model.Results AUC of RMintra,RM+3 mm,RM+5mm,RMintra+3 mm and RMintra+5 mm was 0.750,0.724,0.749,0.833 and 0.807 in training set,while was 0.723,0.718,0.736,0.759 and 0.782 in test set,respectively.In training set,significant differences of AUC was found(all P＜0.01),while in test set,no significant difference of AUC was found among models(all P＞0.05).The calibrations of models were all high.DCA showed that taken 0.02-0.88 as the threshold,the clinical net benefit of RMintra+per were greater in training set,while taken 0.40-0.72 as the threshold,the clinical net benefit of RMintra+per was greater in test set.Conclusion Both DWI intratumoral and peritumoral radiomics could effectively predict histological grade of breast cancer.Combination of intratumoral and peritumoral radiomics was more effective.

Pulmonary blast injury has become the main type of trauma in modern warfare, characterized by externally mild injuries but internally severe injuries, rapid disease progression, and a high rate of early death. The injury is complicated in clinical practice, often with multiple and compound injuries. Currently, there is a lack of effective protective materials, accurate injury detection instrument and portable monitoring and transportation equipment, standardized clinical treatment guidelines in various medical centers, and evidence-based guidelines at home and abroad, resulting in a high mortality in clinlcal practice. Therefore, the Trauma Branch of Chinese Medical Association and the Editorial Committee of Chinese Journal of Trauma organized military and civilian experts in related fields such as thoracic surgery and traumatic surgery to jointly develop the Clinical treatment guideline for pulmonary blast injury ( version 2023) by combining evidence for effectiveness and clinical first-line treatment experience. This guideline provided 16 recommended opinions surrounding definition, characteristics, pre-hospital diagnosis and treatment, and in-hospital treatment of pulmonary blast injury, hoping to provide a basis for the clinical treatment in hospitals at different levels.

Objective:To investigate the vitamin D level of pulmonary tuberculosis patients in Qinghai Province, and to explore the correlation between vitamin D level and pulmonary tuberculosis.Methods:From May to September 2020, 208 bacterial confirmed pulmonary tuberculosis patients who were admitted to The 4th People′s Hospital of Qinghai Province were enrolled as the pulmonary tuberculosis group, and 129 healthy people who underwent physical examination during the same period were enrolled as the healthy control group. Independent sample t test and chi-square test were used for statistical analysis. Results:The deficiency rate of vitamin D was 11.06%(23/208) in the pulmonary tuberculosis group, which was higher than that (3.10%(4/129)) in the healthy control group, and the difference was statistically significant ( χ2=6.840, P=0.009). The vitamin D level was (56.84±20.03) μg/L in the pulmonary tuberculosis group, which was lower than that ((67.39±17.07) μg/L) in the healthy control group, and the difference was statistically significant ( t=5.154, P<0.01). The vitamin D levels were not different between the newly treated ((56.66±20.02) μg/L)) and retreated pulmonary tuberculosis patients ((59.11±20.81) μg/L) ( t=0.468, P=0.650). The vitamin D level of simple pulmonary tuberculosis patients ((57.82±20.01) μg/L) was higher than that of pulmonary tuberculosis patients combined with other diseases ((48.08±18.46) μg/L), and the difference was statistically significant ( t=2.132, P=0.034). Conclusion:Pulmonary tuberculosis is associated with decreased vitamin D levels, and patients with pulmonary tuberculosis are more likely to suffer from decreased or deficient vitamin D, which suggests clinicians considering the vitamin D status when treating pulmonary tuberculosis patients.

Antibodies, Neutralizing/immunology* ; Antibodies, Viral/immunology* ; COVID-19/virology* ; COVID-19 Vaccines/immunology* ; Humans ; SARS-CoV-2/pathogenicity* ; Spike Glycoprotein, Coronavirus/immunology* ; Vaccines, Inactivated/immunology*