Objective:Laboratory evaluation of the relationship between cerebrospinal fluid and plasma indicators and intrathecal immunoglobulin G(IgG) synthesis in patients with neurological diseases, and establishment of a new diagnostic method for intrathecal IgG synthesis.Methods:This study retrospectively analyzed the content of IgG in cerebrospinal fluid samples and blood albumin in blood samples, and other test results of 410 patients with neurological diseases who visited Beijing Tiantan Hospital from 2019 to 2022. According to the results of oligoclonal bands in cerebrospinal fluid, patients were divided into intrathecal IgG synthesis group and non-intrathecal IgG synthesis group. The Mann Whitney U test was used for inter group comparison, and a bilateral test with P<0.05 indicates a statistically significant difference. Include indicators with differences between groups in logistic regression analysis, construct a predictive model, and compare it with the established quantitative formula IgG index. Results:There were significant differences in 10 indicators, including cerebrospinal fluid leukocyte count and 24-hour intrathecal IgG synthesis rate, between the intrathecal IgG synthesis group and the non-intrathecal IgG synthesis group, with P<0.05. The area under the curve (AUC) of intrathecal IgG synthesis was higher than the IgG index (AUC=0.920, 0.809, Z=31.178, P<0.001), the sensitivity was higher than the IgG index (0.825, 0.618), and the specificity was lower than the IgG index (0.876, 0.908). Conclusion:The combination of 10 indicators such as cerebrospinal fluid white blood cell count and 24-hour intrathecal IgG synthesis rate can improve the diagnostic efficacy and sensitivity of intrathecal IgG synthesis.

Objective To evaluate the value of intrathecal synthetic related markers in patients with mild cognitive impairment(MCI),Alzheimer's disease(AD),and other types of dementia.Methods Retrospec-tively collect the clinical data of 577 patients diagnosed with MCI(MCI group,178 cases),AD(AD group,131 cases),and other types of dementia(other types group,268 cases)from June 2019 to July 2023 in Beijing Tiantan Hospital,Capital Medical University.Oligoclonal zone electrophoresis(OCB)and 24 h intrathecal pro-tein synthesis rate(ISR)of each group were investigated,and the difference of different indexes among the groups was compared to evaluate the value of related indexes in the differential diagnosis of different diseases.Results Compared with AD group and other groups,AD group had a higher proportion of females,more patients were＞50-70 years old,and the incidence of abnormal lipid metabolism was higher,with statistical significance(P＜0.05).There were significant differences in OB(S),cerebrospinal fluid albumin,serum albumin and cerebrospinal flu-id IgG in different disease groups(P＜0.05).IgG index and ISR in patients with positive SOB(CSF)were higher than those in negative and weakly positive patients,and the differences were statistically significant(P＜0.001).IgG index was positively correlated with ISR(r=0.878,P＜0.001).Conclusion Intrathecal synthetic mark-ers such as IgG index,SOB(CSF)and 24 h ISR have synergistic effects in the diagnosis of cognitive dysfunction and various dementias,which can be collectively utilized in the diagnosis of diseases.

Objective To analyze the basic case data and laboratory test index characteristics of patients with myasthenia gravis(MG),so as to evaluate the application value of common clinical laboratory indicators in the construction of a diagnostic model for MG.Methods A retrospective analysis was performed on the basic data and laboratory indicators of MG patients and gender and age-matched healthy controls diagnosed at Beijing Tiantan Hospital,Capital Medical University from April 2021 to April 2023.A diagnostic model was constructed,and the receiver operating characteristic(ROC)curve was drawn to analyze the area under the curve(AUC).Results The BMI,heart rate,systolic blood pressure,and diastolic blood pressure in the MG group were significantly higher than those in the control group,with statistical significance(P＜0.05).There were significant differences in total protein,albumin,white blood cell count,proportion of large platelets,abso-lute value of monocyte and triiodothyronine between MG group and control group(P＜0.05).Seven indexes of heart rate,diastolic blood pressure,albumin,creatine kinase,cholinesterase,triglyceride and apolipoprotein B were selected to construct the diagnostic model.The area under the curve of the combined application of multiple indexes could reach 0.995,with a sensitivity and specificity of 97.60％and 96.10％,respectively.Conclusion In this study,the laboratory test indexes that can be used for the diagnosis of MG are successfully selected,and the sensitivity and specificity of the combined application of multiple indexes are high,which can be used for the auxiliary diagnosis of MG.

Objective To analyze the distribution characteristics and application value of liver,renal func-tion indexes and autoantibody-related indexes of neuromyelitis optica spectrum disorder(NMOSD).Methods The liver,renal function and autoantibody-related indexes data of patients diagnosed with NMOSD and multiple sclerosis(MS)in Beijing Tiantan Hospita,Capital Medical University from June 2015 to June 2023,as well as gender and age-matched controls underwent routine physical examination were retrospectively collected.A total of 95 patients with NMOSD(NMOSD group),230 patients with MS(MS group),and 244 healthy controls(routine physical examination group)were selected to evaluate the diagnostic value of each index for NMOSD.Results Compared with MS group,the levels of alanine aminotransferase,as well as the positive rates of α-hydroxybutyrate dehydrogenase,y-glutamyltransferase,anti-SS-A antibody,anti-SS-B anti-body,anti-ribosomal P protein antibody and Ro-52 antibody were significantly increased in NMOSD group,while the levels of albumin,indirect bilirubin and total bilirubin were significantly decreased,and the differ-ences were statistically significant(P＜0.05).The difference index between NMOSD and conventional physi-cal examination group was similar to that of MS group.The seven indexes,a-hydroxybutyrate dehydrogenase,albumin,globulin,direct bilirubin,indirect bilirubin,total bile acid and uric acid alkalinity could be used for the diagnosis of NMOSD.The area under the curve of combined diagnosis of NMOSD was 0.969,and the sensitiv-ity and specificity were 92.6％and 92.9％.Conclusion Multiple indexes of liver and kidney function in NMOSD patients are different from those in MS patients and healthy subjects underwent routine physical ex-amination,and the positive rate of some autoantibody indexes in NMOSD patients is higher than that in MS patients.Liver,renal function and autoantibody-related indexes can be used clinically to assist diagnosis,and the combined application of multiple indexes can further enhance its diagnostic value.

Objective To investigate the clinical significance of combined cerebrospinal fluid(CSF)and routine blood parameter analysis in differentiating between multiple cerebral glioma(MCG)and primary central nervous system lymphoma(PCNSL).Methods We Rretrospectively analyzed the clinical data,CSF and routine blood indicators levels of 62 MCG patients and 56 PCNSL patients admitted to Beijing Tiantan Hospital,Capital Medical University from November 2017 to March 2023.Additionally,we assessed the diagnostic value of individual meaningful indicators as well as their combinations in distinguishing between MCG and PCNSL.Results The levels of CSF total cell count,CSF white cell count,CSF:pro,lactate,routine bloodperipheral neutrophil count,and neu-trophil percentage were significantly higher in the MCG group than in the PCNSL group(P<0.05);while the levels of CSF:Glu,CSF:cl,routine blood lymphocyte count,eosinophil,lymphocyte percentage,and eosinophil percent-age were significantly higher in the PCNSL group than in the MCG group(P<0.05).The AUCs of CSF cell count,CSF white cell count,CSF:pro,lactate,routine blood neutrophil count,neutrophil percentage for differentiating MCG from PCNSL were 0.900,0.899,0.797,0.867,0.828 and 0.772 respectively;sensitivities were 72.4%,77.6%,63.8%,67.2%,72.4%,82.8%,77.6%and 81%,with sensitivities of 97.1%,100%,88.2%,91.2%,88.2%,64.7%,100%and 94.1%,respectively.In addition,the combined detection of CSF total cell count,CSF white cell count,CSF:pro,routine blood neutrophil count and neutrophil percentage in CSF had an AUC of 0.919 for differentiating MCG from PCNSL,with a sensitivity and specificity of 77.6%and 100%,respectively.Conclusions Combined detection of CSF indicators including CSF total cell count,CSF white cell count,CSF:pro,along with routine blood markers such as neutrophil count and neutrophil percentage,holds significant clinical utility for differ-entiating between MCG and PCNSL.

Single-molecule immunoassay technology represents an ultrasensitive immunoassay method that enables the resolution and detection of individual biomolecules at the nanoscale. This article highlights various representative techniques and clinical applications of single-molecule immunoassay technology, while also discussing the current challenges and future development directions. Through multiple optimizations at both the technical and commercial levels, single-molecule immunoassay technology exhibits unique advantages in real-time detection, disease diagnosis and treatment, and medical research. This technology is poised to contribute to the advancement of precision medicine by integrating individualized detection methods into clinical practice.

Objective:To establish and verify a diagnostic model for distinguishing multiple sclerosis (MS) from other neurological diseases with similar symptoms by usingcerebrospinal fluid oligoclonal band (CSF-OCB)combined with IgG intrathecal synthesis indicators and biochemical markers.Methods:Multiple sclerosis (MS) patients admitted to the Neurology Department of Beijing Tiantan Hospital affiliated with Capital Medical University from January 2014 to December 2022 were selected as the case group, while patients with similar neurological symptoms were selected as the control group. Using the case-control study design, a retrospective analysis was conducted on the detection of age, gender, oligoclonal bands in cerebrospinal fluid, IgG intrathecal synthesis indicators and biochemical indicators for all study subjects. The differential diagnosis model was determined by the multiple logistic regression analysis, and the receiver operating characteristic (ROC) curve was used to analyze the diagnostic efficiency of the differential diagnosis model for neurological diseases with similar symptoms to MS and other conditions.Results:This study included 167 patients in the case group and 335 patients in the control group, of which 128 patients in the case group and 265 patients in the control group were used to construct the model, and 39 patients in the case group and 70 patients in the control group were used for model validation. The differential diagnostic model constructed by a multivariate logistic regression model was Y=0.871×CSF-OCB-0.051×CSFprotein-0.231×CSFchloride+1.183×gender-0.036×LDH+35.770. The model showed that the area under the curve, sensitivity and specificity were respectively 0.916, 87.3% and 87.6%. The Delong test results showed that the diagnostic efficacy of the model was significantly different from OCB, IgG intrathecal synthesis indicators, and OCB combined with IgG intrathecal synthesis indicators ( P<0.05). The new model validation showed that the actual diagnostic consistency rate for the MS group was 84.6%, while the actual diagnostic consistency rate for the control group was 90.0%. Conclusion:This study combines OCB, IgG intrathecal synthesis indicators, and biochemical indicators to establish a diagnostic prediction model for neurological diseases with similar clinical symptoms in MS. This model may have good differential diagnostic value and can better assist clinical diagnosis in the early stages of disease progression in MS patients.

Single-molecule immunoassay technology represents an ultrasensitive immunoassay method that enables the resolution and detection of individual biomolecules at the nanoscale. This article highlights various representative techniques and clinical applications of single-molecule immunoassay technology, while also discussing the current challenges and future development directions. Through multiple optimizations at both the technical and commercial levels, single-molecule immunoassay technology exhibits unique advantages in real-time detection, disease diagnosis and treatment, and medical research. This technology is poised to contribute to the advancement of precision medicine by integrating individualized detection methods into clinical practice.

Objective:To establish and verify a diagnostic model for distinguishing multiple sclerosis (MS) from other neurological diseases with similar symptoms by usingcerebrospinal fluid oligoclonal band (CSF-OCB)combined with IgG intrathecal synthesis indicators and biochemical markers.Methods:Multiple sclerosis (MS) patients admitted to the Neurology Department of Beijing Tiantan Hospital affiliated with Capital Medical University from January 2014 to December 2022 were selected as the case group, while patients with similar neurological symptoms were selected as the control group. Using the case-control study design, a retrospective analysis was conducted on the detection of age, gender, oligoclonal bands in cerebrospinal fluid, IgG intrathecal synthesis indicators and biochemical indicators for all study subjects. The differential diagnosis model was determined by the multiple logistic regression analysis, and the receiver operating characteristic (ROC) curve was used to analyze the diagnostic efficiency of the differential diagnosis model for neurological diseases with similar symptoms to MS and other conditions.Results:This study included 167 patients in the case group and 335 patients in the control group, of which 128 patients in the case group and 265 patients in the control group were used to construct the model, and 39 patients in the case group and 70 patients in the control group were used for model validation. The differential diagnostic model constructed by a multivariate logistic regression model was Y=0.871×CSF-OCB-0.051×CSFprotein-0.231×CSFchloride+1.183×gender-0.036×LDH+35.770. The model showed that the area under the curve, sensitivity and specificity were respectively 0.916, 87.3% and 87.6%. The Delong test results showed that the diagnostic efficacy of the model was significantly different from OCB, IgG intrathecal synthesis indicators, and OCB combined with IgG intrathecal synthesis indicators ( P<0.05). The new model validation showed that the actual diagnostic consistency rate for the MS group was 84.6%, while the actual diagnostic consistency rate for the control group was 90.0%. Conclusion:This study combines OCB, IgG intrathecal synthesis indicators, and biochemical indicators to establish a diagnostic prediction model for neurological diseases with similar clinical symptoms in MS. This model may have good differential diagnostic value and can better assist clinical diagnosis in the early stages of disease progression in MS patients.

Objective: To examine the prevalence and factors influencing the inconsistency for knowledge and behavior in condom use among college students, so as to provide suggestions for AIDS prevention and education in universities. Methods: From October to December 2019, a multistage cluster sampling method was employed to collect data relating to inconsistency for knowledge and behavior in condom use and other related factors among 1 303 students from six colleges in Zhuhai, China. Chi square test and Logistic regression were performed to analyze the influencing factors and moderating effect. Results: The reporting rate of in consistency of knowledge and behavior in condom use among college students was 41.1%. Multivariate Logistic regression analysis showed that seeking sexual partners offline was negatively correlated with inconsistency for knowledge and behavior in condom use ( OR=0.70, 95%CI =0.51-0.95). However, condom nonuse during the first sexual experience (OR=7.11, 95%CI=5.23-9.67), smoking before sex ( OR=1.47, 95%CI =1.07-2.02), drinking before sex ( OR=1.44, 95%CI =1.09-1.91), history of intimate partner violence ( OR=1.53, 95%CI =1.13-2.07), and having multiple sexual partners ( OR=1.69, 95%CI =1.25-2.29) were positively correlated with inconsistency for knowledge and behavior in condom use ( P <0.05). The moderating effect analysis showed that condom use during the first sexual experience had a moderating effect on smoking before sex and inconsistency for knowledge and behavior in condom use ( β=0.92, P <0.05). Among students who did not use condoms during the first sexual experience, a positive correlation was observed between smoking before sex and inconsistency for knowledge and behavior in condom use ( OR= 2.76 , 95%CI=1.09-6.99, P <0.05). However, no correlation was found between smoking before sex and inconsistency for knowledge and behavior in condom use ( OR=1.32, 95%CI=0.92-1.88, P >0.05) among students who used condoms during the first sexual experience. Conclusion High levels of inconsistency for knowledge and behavior in condom use are found among college students in Zhuhai City. Colleges should carry out sex education activities as soon as possible, and explore new health education models to promote the transformation of their knowledge into behavior.