By engineering the subsite +1 of cyclodextrin glycosyltransferase (CGTase) from Paenibacillus macerans, we improved its maltodextrin specificity for 2-O-D-glucopyranosyl-L-ascorbic acid (AA-2G) synthesis. Specifically, we conducted site-saturation mutagenesis on Leu194, Ala230, and His233 in subsite +1 separately and gained 3 mutants L194N (leucine --> asparagine), A230D (alanine --> aspartic acid), and H233E (histidine --> glutamic acid) produced higher AA-2G yield than the wild-type and the other mutant CGTases. Therefore, the 3 mutants L194N, A230D, and H233E were further used to construct the double and triple mutations. Among the 7 obtained combinational mutants, the triple mutant L194N/A230D/H233E produced the highest AA-2G titer of 1.95 g/L, which was increased by 62.5% compared with that produced by the wild-type CGTase. Then, we modeled the reaction kinetics of all the mutants and found a substrate inhibition by high titer of L-AA for the mutants. The optimal temperature, pH, and reaction time of all the mutants were also determined. The structure modeling indicated that the enhanced maltodextrin specificity may be related with the changes of hydrogen bonding interactions between the side chain of residue at the three positions (194, 230 and 233) and the substrate sugars.
Ascorbic Acid ; analogs & derivatives ; chemistry ; Glucosyltransferases ; genetics ; metabolism ; Hydrogen Bonding ; Kinetics ; Mutagenesis, Site-Directed ; Paenibacillus ; enzymology ; Polysaccharides ; chemistry ; Protein Engineering ; Substrate Specificity ; Temperature

To study the chemical constituents of Fructus Xanthii and to determine the contents of total phenolic acids (TPA) in fruits of Xanthium from different populations for evaluating the quality of them.

OBJECTIVE: To investigate the effects of Liriope platyphylla total saponin (LPTS) on learning, memory, neuromediators and metabolites in aging mice induced by D-galactose. METHODS: Ninety Kunming mice were randomly divided into nine groups: normal saline (NS)-treated group, untreated group, high- (100 mg/kg), medium- (50 mg/kg) and low-dose (10 mg/kg) LPTS-treated groups, Shuxuening-treated group, jiaogulanosidi-treated group, flunarizine-treated group and vitamin E-treated group. The Kunming mice in the NS-treated group were administered with NS by intraperitoneal injection, while the aging mice in the other eight groups were administered with D-galactose by intraperitoneal injection. At the same time, the aging mice in different groups were fed with corresponding drugs for 42 days, and the aging items of the mice in different groups were measured, respectively. RESULTS: LPTS could improve the memory of aging mice induced by D-galactose, promote its body weight, and increase the thymus and spleen indexes of the aging mice. LPTS could decrease the levels of MDA and lipofuscin, inhibit MAO activity and increase SOD activity and GSH-Px level. CONCLUSION: LPTS may improve the ability of learning and memory and delay aging.

To evaluate the antiosteoporotic effects of benzyl benzoate glucosides from Curculigo orchioides (COBG) in ovariectomized (OVX) rats.

Objective To determine the contents of total flavonoids and xanthohumol in hop from 29 different countries and regions .Methods Rutin colorimetric method was used to determine the content of total flavonoids .HPLC-UV method was established for the determination of xanthohumol in hops .HPLC method was performed by Dikma Technologies Diamonsil C18 (250 mm × 4 .6 mm ,5 μm ) column with mobile phase acetonitrile-1％ glacial acetic acid solution at the flow rate of 1 .0 ml/min .The column temperature was 25 ℃ .The detection wavelength was 370 nm .Results The equation of linear re-gression of total flavonoids was A=30 .345C+0 .0168 ,r=0 .9999 .The equation of linear regression of xanthohumol was A=55446 C+9040 .5 ,r=0 .9999 .Their linear ranges were respectively 20 .2-404 .0 μg/ml ,2 .152-43 .040 μg/ml ,which indica-ted a good linear relationship .The RSDs of precision and repeatability were less than 2％ .The average recoveries of flavonoids and xanthohumol were respectively 102 .71％ and 100 .21％ .Conclusion The contents of total flavonoids and xanthohumol in different hops varieties are significantly different and the import hops was better than the domestic hops in this study .

Objective:To explore the prognostic predictive value of detecting minimal residual disease (MRD) after 2 courses of hypomethylating agents (HMA) combined with low-dose induction chemotherapy in patients with acute myeloid leukemia (AML).Methods:The data of 43 newly diagnosed AML patients treated by HMA combined with low-dose induction chemotherapy in Jingjiang People's Hospital of Jiangsu Province from January 2016 to January 2021 were retrospectively analyzed, and the bone marrow MRD levels were detected by multiparametric 10-color flow cytometry (MFC) after 1 course and 2 courses of chemotherapy. Patients were divided into three groups according to MRD levels: the group with negative MRD after 1 course of induction chemotherapy (MRD-1 group), the group with negative MRD after 2 courses of induction chemotherapy (MRD-2 group), and the group without negative MRD after 2 courses of induction chemotherapy (MRD+ group). Kaplan-Meier method was used to draw the progression-free survival (PFS) and overall survival (OS) curves of all patients and each group, and log-rank test was performed to compare them; the influencing factors for OS were analyzed using univariate and multivariate Cox proportional hazards models.Results:Among the 43 patients, 17 patients (39.5%) were in the MRD-1 group, 14 patients (32.6%) were in the MRD-2 group, and 12 patients (27.9%) were in the MRD+ group. There were no statistical differences among the 3 groups in gender, age, hemoglobin level at initial diagnosis, white blood cell count, platelet count, lactate dehydrogenase level, disease subtype, WT1 expression, karyotype, and genetic risk stratification (all P > 0.05). The median follow-up was 15 months (1-67 months). Survival analysis showed a median OS time of 21 months (95% CI 15 months -not reached) in 43 patients and a median PFS time of 12 months (95% CI 9-18 months) in 29 patients included in the PFS analysis; PFS and OS in the MRD-1 and MRD-2 groups were better than those in the MRD+ group (all P < 0.01), and the differences in PFS and OS between the MRD-1 and MRD-2 groups were not statistically significant (both P > 0.05); the median PFS time was 5 months (95% CI 2 months-not reached) in the MRD+ group, the median PFS time was 15 months (95% CI 7 months-not reached) in the MRD-1 group, and the median PFS time was 18 months (95% CI 11 months-not reached) in the MRD-2 group; the median OS time in the MRD+ group was 9 months (95% CI 7 months-not reached), the median OS time was not reached in the MRD-1 group, and the median OS time was 38 months (95% CI 38 months-not reached) in the MRD-2 group. Multivariate Cox regression analysis showed that age ( HR = 1.080, 95% CI 1.004-1.160, P = 0.038), MRD status (MRD-1 vs. MRD+: HR = 0.125, 95% CI 0.031-0.507, P = 0.004; MRD-2 vs. MRD+: HR = 0.146, 95% CI 0.037-0.577, P = 0.006) were independent influencing factors for OS in AML patients. Conclusions:The survival is good in AML patients with MRD negative conversion after both 1 course and 2 courses of HMA combined with low-dose induction chemotherapy, and both are better than that in patients with positive MRD after 2 courses of chemotherapy.

Objective:To investigate the correlation of excessive platelet (Plt) recovery at the first time of achieving morphologic complete remission (CR) after induction chemotherapy with minimal residual disease (MRD) and the clinical features of acute myeloid leukemia (AML).Methods:The clinical data of newly-treated 57 AML patients (except for acute promyelocytic leukemia) who achieved CR after induction chemotherapy in Jinjiang People's Hospital from January 2016 to December 2021 were retrospectively analyzed. A total of 57 newly diagnosed adult AML patients were divided into excessive Plt recovery group (Plt recovery>350×10 9/L) and normal Plt recovery group [Plt recovery: (100-350)×10 9/L] according to the Plt recovery. Meanwhile, the MRD was analyzed by using multiparameter flow cytometry (MFC) in patients achieving CR after receiving 1 course of standard treatment regimen or 1-2 courses of demethylation drugs combined with pre-conditioning regimen. The clinical features and negative rate of MRD between the two groups were compared. Results:Among 57 CR patients, 31 (54.4%) patients had CR with excessive Plt recovery and MFC-MRD negative rate was 67.7% (21/31); 26 (45.6%) had CR with normal Plt recovery and MFC-MRD negative rate was 38.5% (10/26); and the difference in the proportion of MRD negative patients between the both groups was statistically significant ( χ2 = 4.89, P = 0.027). There were no statistically differences in the proportions of patients with different gender, age, WBC at initial diagnosis, Plt, chemotherapy regimen and risk degree classification between the two groups (all P > 0.05). Conclusions:In AML patients, excessive Plt recovery at the first time of achieving morphologic CR after induction chemotherapy is associated with negative MRD, which has a certain value in the judgement of therapeutic effect.

Objective:To explore the status quo of neonatal hypoglycemia (NH) prevention cognition and management among neonatal and obstetric nurses in Jiangsu Province and provide a reference for NH prevention and nursing.Methods:In this cross-sectional study, between May and June 2020, convenience sampling and a self-designed questionnaire were used to investigate neonatal and obstetric nurses from 21 hospitals in 13 cities across Jiangsu Province. The questionnaire encompassed general information, nurses' cognition of NH prevention and care, and differences between nurses' cognition and implementation of departmental NH preventive management system. Totally 331 questionnaires were distributed and 318 were collected, accounting for an effective recovery rate of 91.1%.Results:Among the 318 neonatal and obstetric nurses, the NH diagnosis and intervention thresholds in the hospitals where the neonatal and obstetric nurses worked were 2.2-2.9 mmol/L. Most nurses considered blood glucose levels≤ 2.2 and≤ 2.6 mmol/L as diagnostic and intervention thresholds, accounting for 59.75% (190/318) and 58.18% (185/318) , respectively. Among the open-ended questions, tremor, feeding difficulties, and hypotonia were the most common clinical manifestations of NH mentioned by nurses, and more than 60% of nurese knew that gestational diabetes and macrosomia were high-risk factors for NH.Neonatology and obstetric nurses' approval rate for the department's NH management system was 72.96%-87.11%, and the implementation rate was 46.77%-84.48%. In all projects, the approval rate was higher than the implementation rate. In terms of establishing NH risk assessment, formulating NH screening population table, organizing preventive health education for NH, and regularly analyzing the causes of NH, there were statistically significant differences between nurses' cognition and implementation rate ( P<0.05) . Conclusions:There is a lack of uniform standards for NH management in hospitals in Jiangsu Province. Nurses' cognition of NH assessment, screening and monitoring is quite different, and the recognition rate of NH management systems is higher than the implementation rate. It is necessary to establish a standardized NH prevention and management system and strengthen the implementation of specific systems within the department.

Alkaloids ; Apoptosis ; HL-60 Cells ; Harringtonines ; Humans ; Quinolizines

ObjectiveTo adapt the Stanford Expectations of Treatment Scale（SETS） into Chinese（C-SETS） and test the feasibility， validity and reliability of its application in patients with diarrhea-predominant irritable bowel syndrome（IBS-D） with liver-constraint and spleen-deficiency syndrome treated with traditional Chinese medicine（TCM）. MethodsWe obtained authorisation from the developer of the SETS， and followed the principle of "two-way translation" to translate the SETS by literal translation and back translation to form the C-SETS. Ninety-six IBS-D patients with liver-constraint and spleen-deficiency syndrome were enrolled as respondents and filled out C-SETS before receiving treatment； the feasibility was assessed by the recall rate， completion rate and the duration of filling out the scale； the reliability was assessed by Cronbach's α； the structural validity was assessed by exploratory and confirmatory factor analysis， and the content validity was assessed by correlation analysis. ResultsThe C-SETS consists of 10 items， with the 1st， 3rd， and 5th rating items constituting the Positive Expectations subscale， and the 2nd， 4th， and 6th rating items constituting the Negative Expectations subscale， each of which is rated on a 7-point Likert Scale. The recall of C-SETS was 100%（96/96）， the completion rate was 89.58%（86/96）； Cronbach's α for the Positive and Negative Treatment Expectations subscales were 0.845 and 0.854， respectively； exploratory factor analysis showed that the coefficient of commonality for all six entries was larger than 0.4， and that the six entries could be used by both factors to explain 77.092% of the total variance； validation factor analysis showed that the goodness-of-fit index， comparative fit index， root mean square of approximation error， canonical fit coefficient， and chi-square degrees of freedom ratio took the values of 0.943， 1.003， 0， 0.943， and 0.626， respectively； and the results of Spearman's analysis suggested that the C-SETS had good content validity. ConclusionThe C-SETS has well feasibility， reliability， and validity， which initially proves that it can be used as a tool to assess the treatment expectation of patients with IBS-D with liver-constraint and spleen-deficiency syndrome before receiving TCM treatment.