Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.

High-performance liquid chromatography(HPLC) was used to determine the content of three major components in Citri Reticulatae Semen(CRS), including limonin, nomilin, and obacunone. The chromaticity of the CRS sample during salt processing and stir-frying was measured using a color difference meter. Next, the relationship between the color and content of the salt-processed CRS sample was investigated through correlation analysis. By integrating the oil bath technique for processing simulation with HPLC, the changes in the relative content of nomilin and its transformation products were analyzed, with its structural transformation pattern during processing identified. Additionally, RAW264.7 cells were induced with lipopolysaccharides(LPSs) to establish an inflammatory model, and the anti-inflammatory activity of nomilin and its transformation product, namely obacunone was evaluated. The results indicated that as processing progressed, E~*ab and L~* values showed a downward trend; a~* values exhibited a slow increase over a certain period, followed by no significant changes, and b~* values remained stable with no significant changes over a certain period and then started to decrease. The limonin content remained barely unchanged; the nomilin content decreased, and the obacunone increased significantly. The changing trends in content and color parameters during salt-processing and stir-frying were basically consistent. The content of nomilin and obacunone was significantly correlated with the colorimetric values(L~*, a~*, b~*, and E~*ab), while limonin content showed no significant correlation with these values. By analyzing HPLC patterns of nomylin at different heating temperatures and time, it was found that under conditions of 200-250 ℃ for heating of 5-60 min, the content of nomilin significantly decreased, while the obacunone content increased pronouncedly. The in vitro anti-inflammatory activity results indicated that compared to the model group, the group with a high concentration of nomilin and the groups with varying concentrations of obacunone showed significantly reduced release of nitric oxide(NO)(P<0.01). When both were at the same concentration, obacunone showed better performance in inhibiting NO release. In this study, the obvious correlation between the color and content of major components during the processing of CRS samples was identified, and the dynamic patterns of quality change in CRS samples during processing were revealed. Additionally, the study revealed and confirmed the transformation of nomilin into obacunone during processing, with the in vitro anti-inflammatory activity of obacunone significantly greater than that of nomilin. These findings provided a scientific basis for CRS processing optimization, tablet quality control, and its clinical application.
Mice ; Animals ; Drugs, Chinese Herbal/pharmacology* ; RAW 264.7 Cells ; Limonins/chemistry* ; Chromatography, High Pressure Liquid ; Citrus/chemistry* ; Color ; Benzoxepins/chemistry* ; Anti-Inflammatory Agents/chemistry*

Combined seawater Hf and Nd isotope compositions have been applied as reliable tracers of water mass mixing and weathering input changes.The establishment of standardized synchronous extraction methods for Fe-Mn oxyhydroxide in sediments,which serve as effective carriers for isotopic signals of ancient seawater,is a prerequisite and key for paleoceanography research.The research material of this study was the surface sediments of the Western Arctic Ocean obtained from China's 7th Arctic Scientific Expedition,and a reliable simultaneous Nd-Hf isotope extraction method in Fe-Mn oxyhydroxide fraction was established through systematic optimization of pretreatment procedures and key extraction parameters.This research focused on analyzing the effects of pretreatment(Milli-Q water pre-wash)and key extraction parameters(leaching time,solution/solid ratios,concentration of EDTA-2Na,and concentration of mixed solution of hydroxyamine hydrochloride(HH)and acetic acid(HAc))on element extraction efficiency and isotopic composition.The experimental results indicated that the Milli-Q water pre-wash was not necessary,Fe-Mn oxyhydroxide extraction could be directly performed.Nd extraction amount in Fe-Mn oxyhydroxide fraction was not sensitive to changes in extraction conditions,while the Hf extraction amount was significantly affected by leaching time,solution/solid ratios and concentration of EDTA-2Na.The optimal conditions for synchronously extracting Nd-Hf isotopes were as follows:adding 20 mL of a mixed solution of 0.005 mol/L HH+1.5%HAc+0.03 mol/L EDTA-2Na per gram of sample,and reaction at room temperature for 3 h under shaking.Through systematic verification of 87Sr/86Sr ratio,εNd value,εHf value,Al/Nd ratio and Al/Hf ratio,it was confirmed that this method could effectively avoid interferences from residual components and accurately obtain Nd-Hf isotope signals of ancient seawater preserved in sediments.The standardized method established in this work provided reliable technical support for reconstructing water mass mixing between the Arctic,North Atlantic,and North Pacific Oceans and riverine input histories.It also provided important reference for the extraction methods of Nd and Hf isotopes from marine sources in sediments from other sea areas around the world.

Objective To understand the respiratory protection competency of staff in hospitals.Methods Staff from six hospitals of different levels and characteristics in Beijing were selected,including doctors,nurses,medical technicians,and servicers,to conduct knowledge assessment on respiratory protection competency.According to exposure risks of respiratory infectious diseases,based on actual cases and daily work scenarios,content of respira-tory protection competency assessment was designed from three aspects:identification of respiratory infectious di-seases,transmission routes and corresponding protection requirements,as well as correct selection and use of masks.The assessment included 6,6,and 8 knowledge points respectively,with 20 knowledge points in total,all of which were choice questions.For multiple-choice questions,full marks,partial marks,and no mark were given respective-ly if all options were correct,partial options were correct and without incorrect options,and partial options were correct but with incorrect options.Difficulty and discrimination analyses on question of each knowledge point was conducted based on classical test theory.Results The respiratory protection competency knowledge assessment for 326 staff members at different risk levels in 6 hospitals showed that concerning the 20 knowledge points,more than 60％participants got full marks for 6 points,while the proportion of full marks for other questions was relatively low.Less than 10％participants got full marks for the following 5 knowledge points:types of airborne diseases,types of droplet-borne diseases,conventional measures for the prevention and control of healthcare-associated infec-tion with respiratory infectious diseases,indications for wearing respirators,and indications for wearing medical protective masks.Among the 20 knowledge questions,5,1,and 14 questions were relatively easy,medium,and difficult,respectively;6,1,4,and 9 questions were with discrimination levels of ≥0.4,0.30-0.39,0.20-0.29,and ≤0.19,respectively.Conclusion There is still much room for hospital staff to improve their respiratory protection competency,especially in the recognition of diseases with different transmission routes and the indications for wearing different types of masks.

Hydrogen sulfide,as a third gas signal molecule and neurotransmitter,can play a neuroprotective role by anti-oxidative stress,anti-inflammatory response,metabolic inhibition and other mechanisms.It is of great significance for the occurrence and development of neurodegenerative diseases including Alzheimer's disease(AD)and Parkinson's disease(PD)mediated by neuroinflammation.This article reviews the research progress of hydrogen sulfide and neuroinflammation and its mediated neurodegenerative diseases,so as to provide new ideas for the treatment of neurodegenerative diseases.

Objective To investigate the effects of intrauterine perfusion with granulocyte colony-stimulating factor(G-CSF)on the endometrial thickness,volume,and blood flow parameters of patients with thin endometrium and their clinical outcomes.Methods We designed a prospective non-randomized synchronous controlled trial and recruited patients with thin endometrium who underwent frozen-thawed embryo transfer(FET)at Mianyang Central Hospital between September 1,2021 and September 1,2023.They were divided into two groups,an experimental group of patients who received the experimental treatment of intrauterine perfusion with G-CSF and a control group of patients who did not receive the experimental treatment.The general data and the clinical outcomes of the two groups were analyzed and compared.The endometrial thickness,volume and blood flow parameters of patients in the experimental group before and after intrauterine perfusion with G-CSF were analyzed.Results The clinical data of 83 patients were included in the study.The experimental group included 51 cases,while the control group included 31 cases.There were no significant differences in the baseline data between the two groups.The clinical pregnancy rate of the experimental group(56.86% )was higher than that of the control group(50.00% )and the rate of spontaneous abortion in the experimental group(27.59% )was lower than that in the control group(37.50% ),but the differences were not statistically significant(P>0.05).In the experimental group,the postperfusion endometrial thickness([0.67±0.1]cm)was greater than the preperfusion endometrial thickness([0.59±0.09]cm),the postperfusion([1.84±0.81]cm3)was greater than the preperfusion endometrial volume([1.54±0.69]cm3),and the postperfusion vascularization flow index(VFI)(1.97±2.82)was greater than the preperfusion VFI(0.99±1.04),with all the differences being statistically significant(P<0.05).Conclusion Intrauterine perfusion with G-CSF can enhance the endometrial thickness,volume,and some blood flow parameters in patients with thin endometrium.

Objective: To describe the prevalence of alcohol consumption and the burden of hemorrhagic stroke and hypertensive heart disease attributed to alcohol consumption in adults aged ≥20 years in 31 provinces in China from 2005 to 2018. Methods: Data from several national representative surveys was used to estimate provincial alcohol exposure level of adults aged ≥20 years from 2005 to 2018 by using kriging interpolation and locally weighted regression methods. Global disease burden research method and data, and China's death cause surveillance data were used to calculate the population attributable fraction (PAF) of hemorrhagic stroke and hypertensive heart disease and the deaths due to alcohol consumption in men and women aged ≥20 years in 31 provinces in China. China census data of 2010 were used to calculate the attributable standardized mortality rate. Results: In 2005 and 2018, the prevalence of alcohol consumption was 58.7% (95%CI: 57.8%-59.5%) and 58.4% (95%CI: 57.6%-59.3%), respectively, in men and 17.0% (95%CI: 16.6%-17.4%) and 18.7% (95%CI:18.1%-19.3%), respectively, in women. The daily alcohol intake was 24.6 (95%CI: 23.8-25.3) g and 27.7 (95%CI: 26.8-28.7) g, respectively, in men and 6.3 (95%CI: 6.0-6.5) g and 5.3 (95%CI: 5.0-5.6) g, respectively, in women. Alcohol exposure level was higher in the provinces in central and eastern China than in western provinces. The lowest exposure level was found in northwestern provinces. From 2005 to 2018, the PAF of hemorrhagic stroke death due to alcohol consumption increased from 5.5% to 6.8%, the attributable deaths increased from 50 200 to 59 100, while the PAF of hypertensive heart disease death due to alcohol consumption increased from 7.0% to 7.7%, the attributable deaths increased from 15 200 to 29 300. The PAF of hypertensive heart disease and hemorrhagic stroke was higher in men than in women, and in central and eastern provinces than in western provinces. In 2018, the standardized mortality rates of hemorrhagic stroke and hypertensive heart disease attributed to alcohol consumption were 4.58/100 000 and 2.11/100 000, respectively. Conclusions: The prevalence of alcohol consumption in men and daily alcohol intake of drinkers were relatively high in China, especially in eastern provinces. Alcohol exposure level was lower in women than in men. Regional measures should be taken to reduce the alcohol intakes in men and current drinkers in order to reduce the health problems caused by alcohol consumption.
Adult ; Male ; Humans ; Female ; Hemorrhagic Stroke ; Hypertension/epidemiology* ; Alcohol Drinking/epidemiology* ; Heart Diseases/epidemiology* ; China/epidemiology*

Objective: To estimate the risk for type 2 diabetes mellitus (T2DM) death attributed to insufficient whole grain intake in seven regions of China from 2005 to 2018. Methods: Based on China National Nutrition and Health Surveys and China Adult Chronic Disease and Nutrition Surveillance, ordinary Kriging method and locally weighted regression were used to estimate the level of whole grain intake of Chinese residents from 2005 to 2018. Based on the results of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 and Chronic Diseases Risk Factors Surveillance in China, we calculated the population attributable fraction (PAF), attributable death number and attributable mortality rate of T2DM due to insufficient whole grain intake in people aged ≥20 years in different regions of China, and we used the 2010 Chinese census data to compare the changes in T2DM deaths attributed to insufficient intake of whole grains in seven regions of China. Results: The whole grain intake levels of Chinese people over 20 years old in 2002, 2010 and 2015 were 19.0 g/d, 14.3 g/d and 19.8 g/d, respectively. The estimated overall whole grain intake level was 20.1 g/d in Chinese residents in 2018, and the intake level was 19.4 g/d in men and 20.8 g/d in women. Among the seven regions, the intake level was highest in northern China (47.4 g/d) and lowest in southwestern China (6.0 g/d). In 2018, the PAF was lowest in northern China (12.8%) and highest in southwestern China (19.3%). From 2005 to 2018, the PAF varied in the seven regions, and the PAF in northeastern China fluctuated around 18.5%. Other regions showed downward trends, especially in northern China and northwestern China, decreased by 26.4% and 21.2%, respectively. Over the past 14 years, the number of attributable deaths in the seven regions showed upward trends, with the highest annual average growth rate of 6.7% in southern China and the lowest annual average growth rate of 2.4% in northern China. In 2018, the standardized T2DM mortality rate attributed to insufficient whole grain intake in China was 3.13/100 000, and the attributable mortality was 3.21/100 000 in men and 3.05/100 000 in women. The standardized attributable mortality rate was highest in southwestern China (3.97/100 000) and lowest in northern China (1.78/100 000). From 2005 to 2018, the standardized attributable mortality rate increased by 11.5% in men and decreased by 8.1% in women. The standardized attributable mortality rate in southwestern, southern and central China increased by 23.7%, 21.3% and 4.2%, respectively. The standardized attributable mortality rate in northern, northwestern, eastern and northeastern China decreased by 20.9%, 11.0%, 4.5% and 3.9%, respectively. Conclusion: The whole grain intake level of Chinese residents was low, and the whole grain intake of residents in all seven regions should be increased, especially in the southwest, and men should have more whole grain intake than women to reduce the death risk in patients with T2DM.
Adult ; Male ; Humans ; Female ; Young Adult ; Whole Grains ; Diabetes Mellitus, Type 2/epidemiology* ; Risk Factors ; Chronic Disease ; China/epidemiology*

Objective:To analyze the clinical characteristics and risk factors for severe disease of hemorrhagic fever with renal syndrome (HFRS) in underage patients, and to construct the severe disease risk model.Methods:A total of 170 HFRS patients (<18 years old) from the Second Affiliated Hospital of Air Force Medical University (153 cases) and the Second Affiliated Hospital of Xi′an Jiaotong University (17 cases) from January 2009 to December 2021 were included. According to the severity of the disease, the patients were divided into mild and severe groups. Baseline demographic data, symptoms, signs, laboratory examination on admission and prognosis were analyzed between the two groups. Statistical comparisons were performed using the Mann-Whitney U test and chi-square test.Binary logistic regression was used to analyze the independent risk factors of patients with severe disease, and the severe disease risk model was built.The receiver operator characteristic curve was used to analyze the value of the risk model in predicting severity of disease. Results:Among the 170 underage patients, 132 (77.6%) were males, aged (14.9±3.1) years, including 124 cases in mild group and 46 cases in severe group. One hundred and sixty-nine cases (99.4%) had fever, 119 cases (70.0%) had headache, 106 cases (62.4%) had lumbago, 158 cases (92.9%) had skin and mucous congestion, and 101 cases (59.4%) had nausea and vomiting. Renal percussive pain was found in 139(81.8%) patients. The incidence of nausea and vomiting and bleeding of skin and mucosa in the severe group were 71.7%(33/46) and 67.4%(31/46), respectively, which were both higher than those in the mild group (54.8%(68/124) and 44.4%(55/124), respectively), and the differences were statistically significant ( χ2=3.97 and 7.12, respectively, both P<0.05). There were significant differences in platelet count, activated partial thromboplastin time (APTT), serum creatinine (SCr), aspartate aminotransferase, alanine aminotransferase, leukocyte count, total bilirubin and albumin levels between the two groups ( Z=-4.14, -4.04, -4.87, -3.90, -4.07, -2.60, -2.78 and t=2.50, respectively, all P<0.05). Binary logistic regression analysis showed that chemosis (odds ratio ( OR)=8.035, 95% confidence interval (95% CI) 2.946 to 21.916), SCr ( OR=1.010, 95% CI 1.006 to 1.015) and APTT ( OR=1.049, 95% CI 1.003 to 1.098) were the independent risk factors for severe HFRS in the underage patients. The risk model was constructed as: Logit(P)=-10.323+ 2.084×chemosis (no=0, grade Ⅰ=1, grade Ⅱ=2, grade Ⅲ=3)+ 0.010×SCr (μmol/L)+ 0.048×APTT (s). The area under the curve to predict severity of disease in underage HFRS patients was 0.868, with an optimal cut-off value of -4.39, with a sensitivity of 73.90% and a specificity of 91.10%. According to the internal verification of the data of the study based on the severe disease risk model, 34 out of 46 patients with severe disease were severe (sensitivity, 73.91%), 113 out of 124 patients with mild disease were mild (specificity, 91.13%). Conclusions:The clinical manifestations of the underage HFRS patients are not typical.The main manifestations are fever, headache and lumbago, nausea and vomiting, and the incidences of skin and mucous congestion and renal percussive pain are high.Chemosis, SCr and APTT are independent risk factors for severe disease in underage patients with HFRS. The severe disease risk model could effectively predict the severity of disease.

Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum β-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ²=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.
Adolescent ; Brain Abscess ; Child ; Child, Preschool ; Escherichia coli ; Female ; Humans ; Hydrocephalus ; Infant ; Infant, Newborn ; Male ; Meningitis, Bacterial/epidemiology* ; Retrospective Studies ; Streptococcus agalactiae ; Streptococcus pneumoniae ; Subdural Effusion ; beta-Lactamases