The dynamic nexus: exploring the interplay of BMI before, during, and after pregnancy with Metabolic Syndrome (MetS) risk in Chinese lactating women.

BACKGROUND AND AIM: The health implications of BMI and MetS in lactating women are significant. This study aims to investigate the relationship between risk of Mets in lactation and BMI in four stages: pre-pregnancy, prenatal period, 42 days postpartum, and current lactation. METHODS AND RESULTS: A total of 1870 Lactating Women within 2 years after delivery were included from "China Child and Lactating Mother Nutrition Health Surveillance (2016-2017)". Logistic regression model and Restricted cubic spline (RCS) were used to estimate the relationship between BMI and risk of MetS. ROC analysis was used to determine the threshold for the risk of MetS. Chain mediating effect analysis was used to verify the mediating effect. BMI of MetS group in all stages were higher than non-MetS group (P < 0.0001). There were significant positive correlations between BMI in each stage and ORs of MetS during lactation (P < 0.05). The best cut-off values for BMI in the four stages were 23.47, 30.49, 26.04 and 25.47 kg/m2. The non-linear spline test at BMI in 42 days postpartum, current and MetS in lactation was statistically significant (P non-linear = 0.0223, 0.0003). The mediation effect of all chains have to work through lactation BMI. The total indirect effect accounted for 80.95% of the total effect. CONCLUSIONS: The risk of MetS in lactating women is due to a high BMI base before pregnancy and postpartum. High BMI in all stages of pregnancy and postpartum were risk factors for MetS in lactation. BMI during lactation plays a key role in the risk of MetS.

QSAR and molecular docking studies on designing potent inhibitors of SARS-CoVs main protease.

Background: Severe acute respiratory syndrome coronavirus (SARS-CoVs) have emerged as a global health threat, which had caused a high rate of mortality. There is an urgent need to find effective drugs against these viruses. Objective: This study aims to predict the activity of unsymmetrical aromatic disulfides by constructing a QSAR model, and to design new compounds according to the structural and physicochemical attributes responsible for higher activity towards SARS-CoVs main protease. Methods: All molecules were constructed in ChemOffice software and molecular descriptors were calculated by CODESSA software. A regression-based linear heuristic method was established by changing descriptors datasets and calculating predicted IC50 values of compounds. Then, some new compounds were designed according to molecular descriptors from the heuristic method model. The compounds with predicted values smaller than a set point were constantly screened out. Finally, the properties analysis and molecular docking were conducted to further understand the structure-activity relationships of these finalized compounds. Results: The heuristic method explored the various descriptors responsible for bioactivity and gained the best linear model with R2 0.87. The success of the model fully passed the testing set validation, proving that the model has both high statistical significance and excellent predictive ability. A total of 5 compounds with ideal predicted IC50 were found from the 96 newly designed derivatives and their properties analyze was carried out. Molecular docking experiments were conducted for the optimal compound 31a, which has the best compound activity with good target protein binding capability. Conclusion: The heuristic method was quite reliable for predicting IC50 values of unsymmetrical aromatic disulfides. The present research provides meaningful guidance for further exploration of the highly active inhibitors for SARS-CoVs.

Quantification of glutathione in plasma samples by HPLC using 4-fluoro-7-nitrobenzofurazan as a fluorescent labeling reagent.

A rapid and highly sensitive high-performance liquid chromatograpy method with fluorescence detection has been developed for determination of glutathione (GSH) in human plasma. A simple pre-column derivatization procedure with 7-flouro-4-nitrobenzo-2-oxa-1,3-diazole (NBD-F) reagent was employed. The separation of the derivatized glutathione was performed using a mobile phase consisting of phosphate buffer (0.02 mol/L, pH 6.0)-acetonitrile (77:23, v/v) at a flow rate of 1.0 mL/min with the column temperature 2°C. The eluted derivatives were fluorometrically detected at an excitation wavelength 470 nm and an emission wavelength 530 nm. Under the optimum chromatographic conditions, the calibration curve was linear over the range of 0.1 µmol/L to 10.0 µmol/L with the correlation coefficient of 0.9988. The precision of the method was satisfactory with the intra- and inter-day coefficient of variation being 6.3%, 6.9%, respectively. This method has been used to determine glutathione concentrations in plasma samples from healthy individuals.

Determination of taurine in biological samples by high-performance liquid chromatography using 4-fluoro-7-nitrobenzofurazan as a derivatizing agent.

OBJECTIVE: A highly sensitive and rapid high-performance liquid chromatography method with pre-column derivatization with 4-fluoro-7-nitrobenzofurazan was developed for determination of taurine in biological samples, including plasma, brain, and liver. METHODS: The optimum derivatization reaction temperature was 70 °C, and at this temperature the reaction was complete within 3 min. The derivatized taurine was separated using phosphate buffer (0.02 mol/L, pH 6.0):acetonitrile (84:16, v/v) as the mobile phase at a flow rate of 1.0 mL/min, and a column temperature of 25 °C. The taurine derivatives were separated within 20 min (tR:14.5 min) and fluorometrically detected at 530 nm with excitation at 470 nm. RESULTS: The intra- and the inter-day coefficients of variation for the method were 5.3% and 7.7%, respectively. The calibration curve was linear from 0.1 µmol/L to 30.0 µmol/L with a correlation coefficient of 0.9995. CONCLUSION: This method can be used to determine the taurine contents in plasma, brain, and liver from normal rats and human plasma.

Improved determination of D-glucosamine hydrochloride in health foods by HPLC using 7-fluoro-4-nitrobenzo-2-oxa-l,3-diazole as a derivative.

This article presents an improved method to detect D-glucosamine hydrochloride in health foods. A simple precolumn derivatization procedure with 7-flouro-4-nitrobenzo-2-oxa-1,3-diazole (NBD-F) reagent was employed. The separation of the derivatized D-glucosamine hydrochloride (NBD-D-glucosamine hydrochloride) was performed using a mobile phase consisting of acetonitrile, potassium dihydrogen phosphate (0.01 mol/L), and trifluoroacetic acid (350:649.74:0.26, volume ratio) at a flow rate of 1.0 mL/min with the column temperature 35 °C. Under the optimum chromatographic conditions, the peak area of NBD-D-glucosamine hydrochloride compared with its absolute value of the peak area of NBD-D-glucosamine hydrochloride in a standard solution concentration range from 1.0 to 500.0 mg/L showed a good linear calibration (R = 0.9999). Recoveries, at spiked concentrations of 10.0, 40.0, and 500.0 mg/L, varied between 97.2% and 102.6% with relative standard deviations ranging from 0.4% to 1.5%. The present method provides sufficient sensitivity as reflected by the values of limit of detection (LOD) and limit of quantification (LOQ). LOD was determined from the signal-to-noise ratios (S/N) of NBD-D-glucosamine hydrochloride peak of at least 3 in the recovery test at 0.02 mg/L, and the estimated LOQ was 0.06 mg/L (S/N = 10). The proposed method was successfully applicable to detect D-glucosamine hydrochloride in health foods and drugs containing a variety of complex materials.