1.Efficient biosynthesis of γ-aminobutyric acid by rationally engineering the catalytic pH range of a glutamate decarboxylase from Lactobacillus plantarum.
Jiewen XIAO ; Jin HAN ; Zhina QIAO ; Guodong ZHANG ; Wujun HUANG ; Kai QIAN ; Meijuan XU ; Xian ZHANG ; Taowei YANG ; Zhiming RAO
Chinese Journal of Biotechnology 2023;39(6):2108-2125
γ-aminobutyric acid can be produced by a one-step enzymatic reaction catalyzed by glutamic acid decarboxylase. The reaction system is simple and environmentally friendly. However, the majority of GAD enzymes catalyze the reaction under acidic pH at a relatively narrow range. Thus, inorganic salts are usually needed to maintain the optimal catalytic environment, which adds additional components to the reaction system. In addition, the pH of solution will gradually rise along with the production of γ-aminobutyric acid, which is not conducive for GAD to function continuously. In this study, we cloned the glutamate decarboxylase LpGAD from a Lactobacillus plantarum capable of efficiently producing γ-aminobutyric acid, and rationally engineered the catalytic pH range of LpGAD based on surface charge. A triple point mutant LpGADS24R/D88R/Y309K was obtained from different combinations of 9 point mutations. The enzyme activity at pH 6.0 was 1.68 times of that of the wild type, suggesting the catalytic pH range of the mutant was widened, and the possible mechanism underpinning this increase was discussed through kinetic simulation. Furthermore, we overexpressed the Lpgad and LpgadS24R/D88R/Y309K genes in Corynebacterium glutamicum E01 and optimized the transformation conditions. An optimized whole cell transformation process was conducted under 40 ℃, cell mass (OD600) 20, 100 g/L l-glutamic acid substrate and 100 μmol/L pyridoxal 5-phosphate. The γ-aminobutyric acid titer of the recombinant strain reached 402.8 g/L in a fed-batch reaction carried out in a 5 L fermenter without adjusting pH, which was 1.63 times higher than that of the control. This study expanded the catalytic pH range of and increased the enzyme activity of LpGAD. The improved production efficiency of γ-aminobutyric acid may facilitate its large-scale production.
Glutamate Decarboxylase/genetics*
;
Lactobacillus plantarum/genetics*
;
Catalysis
;
gamma-Aminobutyric Acid
;
Hydrogen-Ion Concentration
;
Glutamic Acid
2.Regional analysis of high risk factors of hypertensive disorders in pregnancy with organ or system impairment.
Xin LYU ; Wei Yuan ZHANG ; Jing Xiao ZHANG ; Yu Qian WEI ; Xiao Li GUO ; Shi Hong CUI ; Jian Ying YAN ; Xiao Yan ZHANG ; Chong QIAO ; Rong ZHOU ; Wei Rong GU ; Xian Xia CHEN ; Zi YANG ; Xiao Tian LI ; Jian Hua LIN
Chinese Journal of Obstetrics and Gynecology 2023;58(6):416-422
Objective: To explore the influencing factors of pregnancy-induced hypertensive disorders in pregnancy (HDP) with organ or system impairment in pregnant women, and to analyze and compare the differences of HDP subtypes in different regions of China. Methods: A total of 27 680 pregnant women with HDP with complete data from 161 hospitals in 24 provinces, autonomous regions and municipalities were retrospectively collected from January 1, 2018 to December 31, 2018. According to their clinical manifestations, they were divided into hypertension group [a total of 10 308 cases, including 8 250 cases of gestational hypertension (GH), 2 058 cases of chronic hypertension during pregnancy] and hypertension with organ or system impairment group [17 372 cases, including 14 590 cases of pre-eclampsia (PE), 137 cases of eclampsia, 2 645 cases of chronic hypertension with PE]. The subtype distribution of HDP in East China (6 136 cases), North China (4 821 cases), Central China (3 502 cases), South China (8 371 cases), Northeast China (1 456 cases), Southwest China (2 158 cases) and Northwest China (1 236 cases) were analyzed. By comparing the differences of HDP subtypes and related risk factors in different regions, regional analysis of the risk factors of HDP pregnant women with organ or system impairment was conducted. Results: (1) The proportions of HDP pregnant women with organ or system impairment in Northeast China (79.05%, 1 151/1 456), Central China (68.42%, 2 396/3 502) and Northwest China (69.34%, 857/1 236) were higher than the national average (62.76%, 17 372/27 680); the proportions in North China (59.18%, 2 853/4 821), East China (60.85%, 3 734/6 136) and South China (59.56%, 4 986/8 371) were lower than the national average, and the differences were statistically significant (all P<0.05). (2) Univariate analysis showed that the proportions of primiparas, non-Han, non-urban household registration, irregular prenatal examination and PE history in the hypertension with organ or system impairment group were higher than those in the hypertension group, and the differences were statistically significant (all P<0.05). Multivariate logistic regression analysis showed that primiparas, non-Han, non-urban household registration, irregular prenatal examination and PE history were independent risk factors for HDP pregnant women with organ or system impairment (all P<0.05). (3) Primipara: the rates of primipara in Northeast China, North China and Southwest China were higher than the national average level, while those in South China, Central China and Northwest China were lower than the national average level. Non-Han nationality: the rates of non-Han nationality in Northeast China, North China and Northwest China were higher than the national average, while those in East China, South China and Central China were lower than the national average. Non-urban household registration: the rates of non-urban household registration in Northeast China, North China, and Southwest China were lower than the national average, while those in East China, Central China were higher than the national average. Irregular prenatal examination: the rates of irregular prenatal examination in North China, South China and Southwest regions were lower than the national average level, while those in Northeast China, Central China and Northwest China were higher than the national average level. History of PE: the incidence rates of PE in Northeast China, North China, South China and Southwest China were lower than the national average level, while those in Central China and Northwest China were higher than the national average level. Conclusions: Primiparas, non-Han, non-urban household registration, irregular prenatal examination, and PE history are risk factors for HDP pregnant women with organ or system impairment. Patients in Northeast, Central and Northwest China have more risk factors, and are more likely to be accompanied by organ or system function damage. It is important to strengthen the management of pregnant women and reduce the occurrence of HDP.
Humans
;
Pregnancy
;
Female
;
Hypertension, Pregnancy-Induced/diagnosis*
;
Retrospective Studies
;
Pre-Eclampsia/epidemiology*
;
Risk Factors
;
Incidence
3.Analysis of risk factors of mortality in infants and toddlers with moderate to severe pediatric acute respiratory distress syndrome.
Bo Liang FANG ; Feng XU ; Guo Ping LU ; Xiao Xu REN ; Yu Cai ZHANG ; You Peng JIN ; Ying WANG ; Chun Feng LIU ; Yi Bing CHENG ; Qiao Zhi YANG ; Shu Fang XIAO ; Yi Yu YANG ; Xi Min HUO ; Zhi Xian LEI ; Hong Xing DANG ; Shuang LIU ; Zhi Yuan WU ; Ke Chun LI ; Su Yun QIAN ; Jian Sheng ZENG
Chinese Journal of Pediatrics 2023;61(3):216-221
Objective: To identify the risk factors in mortality of pediatric acute respiratory distress syndrome (PARDS) in pediatric intensive care unit (PICU). Methods: Second analysis of the data collected in the "efficacy of pulmonary surfactant (PS) in the treatment of children with moderate to severe PARDS" program. Retrospective case summary of the risk factors of mortality of children with moderate to severe PARDS who admitted in 14 participating tertiary PICU between December 2016 to December 2021. Differences in general condition, underlying diseases, oxygenation index, and mechanical ventilation were compared after the group was divided by survival at PICU discharge. When comparing between groups, the Mann-Whitney U test was used for measurement data, and the chi-square test was used for counting data. Receiver Operating Characteristic (ROC) curves were used to assess the accuracy of oxygen index (OI) in predicting mortality. Multivariate Logistic regression analysis was used to identify the risk factors for mortality. Results: Among 101 children with moderate to severe PARDS, 63 (62.4%) were males, 38 (37.6%) were females, aged (12±8) months. There were 23 cases in the non-survival group and 78 cases in the survival group. The combined rates of underlying diseases (52.2% (12/23) vs. 29.5% (23/78), χ2=4.04, P=0.045) and immune deficiency (30.4% (7/23) vs. 11.5% (9/78), χ2=4.76, P=0.029) in non-survival patients were significantly higher than those in survival patients, while the use of pulmonary surfactant (PS) was significantly lower (8.7% (2/23) vs. 41.0% (32/78), χ2=8.31, P=0.004). No significant differences existed in age, sex, pediatric critical illness score, etiology of PARDS, mechanical ventilation mode and fluid balance within 72 h (all P>0.05). OI on the first day (11.9(8.3, 17.1) vs.15.5(11.7, 23.0)), the second day (10.1(7.6, 16.6) vs.14.8(9.3, 26.2)) and the third day (9.2(6.6, 16.6) vs. 16.7(11.2, 31.4)) after PARDS identified were all higher in non-survival group compared to survival group (Z=-2.70, -2.52, -3.79 respectively, all P<0.05), and the improvement of OI in non-survival group was worse (0.03(-0.32, 0.31) vs. 0.32(-0.02, 0.56), Z=-2.49, P=0.013). ROC curve analysis showed that the OI on the thind day was more appropriate in predicting in-hospital mortality (area under the curve= 0.76, standard error 0.05,95%CI 0.65-0.87,P<0.001). When OI was set at 11.1, the sensitivity was 78.3% (95%CI 58.1%-90.3%), and the specificity was 60.3% (95%CI 49.2%-70.4%). Multivariate Logistic regression analysis showed that after adjusting for age, sex, pediatric critical illness score and fluid load within 72 h, no use of PS (OR=11.26, 95%CI 2.19-57.95, P=0.004), OI value on the third day (OR=7.93, 95%CI 1.51-41.69, P=0.014), and companied with immunodeficiency (OR=4.72, 95%CI 1.17-19.02, P=0.029) were independent risk factors for mortality in children with PARDS. Conclusions: The mortality of patients with moderate to severe PARDS is high, and immunodeficiency, no use of PS and OI on the third day after PARDS identified are the independent risk factors related to mortality. The OI on the third day after PARDS identified could be used to predict mortality.
Female
;
Male
;
Humans
;
Child, Preschool
;
Infant
;
Child
;
Critical Illness
;
Pulmonary Surfactants/therapeutic use*
;
Retrospective Studies
;
Risk Factors
;
Respiratory Distress Syndrome/therapy*
4.Rational metabolic engineering of Corynebacterium glutamicum for efficient synthesis of L-glutamate.
Jiafeng LIU ; Zhina QIAO ; Youxi ZHAO ; Meijuan XU ; Xian ZHANG ; Taowei YANG ; Zhiming RAO
Chinese Journal of Biotechnology 2023;39(8):3273-3289
L-glutamic acid is the world's largest bulk amino acid product that is widely used in the food, pharmaceutical and chemical industries. Using Corynebacterium glutamicum G01 as the starting strain, the fermentation by-product alanine content was firstly reduced by knocking out the gene encoding alanine aminotransferase (alaT), a major by-product related to alanine synthesis. Secondly, since the α-ketoglutarate node carbon flow plays an important role in glutamate synthesis, the ribosome-binding site (RBS) sequence optimization was used to reduce the activity of α-ketoglutarate dehydrogenase and enhance the glutamate anabolic flow. The endogenous conversion of α-ketoglutarate to glutamate was also enhanced by screening different glutamate dehydrogenase. Subsequently, the glutamate transporter was rationally desgined to improve the glutamate efflux capacity. Finally, the fermentation conditions of the strain constructed using the above strategy were optimized in 5 L fermenters by a gradient temperature increase combined with a batch replenishment strategy. The glutamic acid production reached (135.33±4.68) g/L, which was 41.2% higher than that of the original strain (96.53±2.32) g/L. The yield was 55.8%, which was 11.6% higher than that of the original strain (44.2%). The combined strategy improved the titer and the yield of glutamic acid, which provides a reference for the metabolic modification of glutamic acid producing strains.
Glutamic Acid
;
Corynebacterium glutamicum/genetics*
;
Ketoglutaric Acids
;
Metabolic Engineering
;
Alanine
5.Research on the current status of pharmacy scientific and technological core journals in China
Yang LI ; Qiao-Ni ZHONG ; Jie XIONG ; Lian REN ; Xian-Tao ZENG
China Pharmacist 2023;26(12):535-540
Objective To analyze the characteristics and current situation of pharmaceutical journals sponsored by institutions in China,so as to improve the utilization,quality and dissemination effect of pharmaceutical journals,provide a basis for scientific evaluation and journal quality management,and provide a reference for readers to choose core journals,focus on reading and submitting.Methods The data of pharmaceutical journals sponsored by domestic institutions in China were collected in the"China Science and Technology Journals Citation Report(Core Edition)"compiled by the Institute of Scientific and Technical Information of China in 2023.This paper analyzes the characteristics and current situation of pharmaceutical journals sponsored by institutions in China,and investigates the number,citation frequency,impact factor,and regional distribution of pharmaceutical journals included in the core catalog of science and technology.Results A total of 48 core journals of pharmaceutical science and technology sponsored by domestic institutions were retrieved,and the publication cycle was mainly monthly(52.08% ).The Chinese Pharmaceutical Association is the institution with the largest number of core journals(15);In terms of quantity,15 core pharmaceutical journals in Beijing ranked first,ranking 2nd to 4th:Shanghai(6),Hubei(4),Jiangsu(4);The average total citation frequency in Chongqing was 3123 times,and the average total citation frequency was the highest.Conclusion The distribution of core pharmaceutical journals shows obvious advantages in economically developed regions such as Beijing and Shanghai.The Chinese Pharmaceutical Association,China Pharmaceutical University and the Chinese Academy of Medical Sciences and other institutions have sponsored many pharmaceutical academic journals,with a relatively complete journal system and rich experience in running journals.
6.Effects of shading on photosynthetic physiology and energy metabolism of Asarum forbesii.
Li-Xian LU ; Hong-Zhuan SHI ; Qiao-Sheng GUO ; Kun ZHAO ; Huai-Yang CHANG ; Jie ZOU ; Li-Yuan GUO ; Zhao-Rui YANG
China Journal of Chinese Materia Medica 2022;47(15):4048-4054
Light is the main source for plants to obtain energy.Asarum forbesii is a typical shade medicinal plant, which generally grows in the shady and wet place under the bushes or beside the ditches.It can grow and develop without too much light intensity.This experiment explores the effects of shading on the growth, physiological characteristics and energy metabolism of A.forbesii, which can provide reference and guidance for its artificial planting.In this experiment, A.forbesii was planted under 80%, 60%, 40%, 20% and no shade.During the vigorous growth period, the photosynthetic physiological characteristics such as fluorescence parameters, photosynthetic parameters, photosynthetic pigment content and ultrastructure, as well as the content of mitochondrial electron transport chain(ETC) synthase and nutrients were measured.The results showed that the photosynthetic pigment content, chlorophyll fluorescence parameters and net photosynthesis rate(P_n) decreased with the decrease of shading.Under 20%-40% shading treatment, the plants had damaged ultrastructure, expanded and disintegrated chloroplast, disordered stroma lamella and grana lamella, and increased osmiophi-lic granules and starch granules.The activities of nicotinamide adenine dinucleotide dehydrogenase(NADH), succinate dehydrogenase(SDH), cytochrome C oxidoreductase(CCO) and adenosine triphosphate(ATP) synthasewere positively related to light intensity.With the reduction of shading, the content of total sugar and protein in nutrients increased first and then decreased, and the content was the highest under 60% shade.In conclusion, under 60%-80% shading treatment, the chloroplast and mitochondria had more complete structure, faster energy metabolism, higher light energy-conversion efficiency, better absorption and utilization of light energy and more nutrient synthesis, which was more suitable for the growth and development of A.forbesii.
Asarum
;
Chlorophyll/metabolism*
;
Chloroplasts
;
Energy Metabolism
;
Photosynthesis/physiology*
;
Plant Leaves/metabolism*
7.Comparative analysis on prevalence of tobacco and e-cigarettes uses in junior middle school students in Shanghai, 2013 and 2019.
Xiao Xian JIA ; Kun XU ; Bei Bei CHE ; Jing Rong GAO ; Zhi Yong HUANG ; Jian WANG ; Xiao Xia WEI ; Kun Lei LE ; Zheng Yang GONG ; Yuan Qiao SUN ; Chen Chen XIE ; Jia Cheng XI ; Yu Zhi CHENG ; Zhu Yan ZHUYAN ; Yuan DING ; De CHEN
Chinese Journal of Epidemiology 2022;43(9):1408-1414
Objective: To examine the prevalence and trend of tobacco and e-cigarettes uses and identify the influencing factors for smoking behavior in junior middle school students in Shanghai, and provide data support and scientific basis for the development of tobacco control intervention strategy in adolescents. Methods: Multi-stage stratified random sampling method was used to select junior middle school students in 8 districts and 10 districts in Shanghai in 2013 and in 2019 respectively. Information about tobacco and e-cigarettes uses in the students were collected by using self-administrated questionnaire. The prevalence of tobacco and e-cigarettes uses were calculated, the difference between two years was compared with χ2 test. The influencing factors were identified by multivariate logistic regression analysis. Results: In 2019, the current smoking rate was 0.6% in junior middle school students in Shanghai, and the smoking attempt rate was 2.9%, both were lower than the levels in 2013 (0.7% and 6.9%). The current use rate of e-cigarettes was 0.6% in 2019,with no significant change compared with 2013 (0.6%). The proportion of the students who had heard of e-cigarettes in 2019 (78.4%) was higher than that in 2013 (47.2%). In 2019, the second-hand smoke (SHS) exposure rate at home, in both indoor and outdoor public places and on public transportations was 72.5%, which was slightly lower than the level in 2013 (73.0%), the differences were all significant (P<0.05). In 2019, the students seeing close friend smoking (OR=27.381, 95%CI: 12.037-62.287), seeing someone smoking in school (OR=2.477, 95%CI: 1.155-5.312), believing that SHS may not be harmful (OR=8.471, 95%CI: 1.464-49.005) had higher possibility of smoking. Being aged ≥15 years (compared with being aged ≤12 years, OR=8.688, 95%CI: 1.922-39.266), exposure to SHS in outdoor public place (OR=8.608, 95%CI: 1.048-70.692), close friend smoking (OR=8.115, 95%CI: 1.754-37.545) were positively associated with e-cigarettes use, and believing that smoking results in uncomfortable social contact [compared with believing that smoking results in comfortable social contact (OR=0.105,95%CI: 0.018-0.615)] were negatively associated with e-cigarettes use, the difference was significant (P<0.05). Conclusion: The prevalence of tobacco and e-cigarette uses in junior middle school students in Shanghai remained at a low level in recent years. The SHS exposure rate in junior middle school students is high. Smoking behavior of junior middle school students is closely related to personal attitude and awareness of tobacco, exposure to SHS, peer smoking and the situation of tobacco control in schools. Prevention and intervention should be carried out from multi-dimensions to effectively protect teenagers from tobacco hazards.
Adolescent
;
China/epidemiology*
;
Electronic Nicotine Delivery Systems
;
Humans
;
Prevalence
;
Students
;
Tobacco
;
Tobacco Smoke Pollution
8.A Single-Center Analysis of the Use of G-CSF Combined with Plerixafor to Mobilize Peripheral Blood Hematopoietic Stem Cell from Healthy Related Donors in Allogeneic Hematopoietic Stem Cell Transplantation.
Juan CHEN ; Li-Li YUAN ; Xian ZHANG ; Jia-Li QIAO ; Qing-Xue YIN ; Yue-Mei ZHANG ; Xue-Lian YANG ; Xing-Yu CAO
Journal of Experimental Hematology 2022;30(1):286-291
OBJECTIVE:
To study the effect and safety of G-CSF combined with Plerixafor on the mobilization of peripheral blood hematopoietic stem cells from healthy related donors of allogeneic hematopoietic stem cell transplantation (allo-HSCT).
METHODS:
It was analyzed retrospectively that the data of peripheral blood hematopoietic stem cells from 33 (observation group) related donors mobilized by G-CSF plus Plerixafor in Hebei Yanda Lu Daopei Hospital from April 2019 to April 2021. Bone marrow and peripheral blood hematopoietic stem cells (PBSCs) of these donors were respectively collected on the fourth and fifth day of G-CSF-induced mobilization. Following the administration of Plerixafor on the night of the fifth day, PBSCs were collected on the sixth day once again. 46 donors using "G-CSF only" mobilization method in the same period were randomly selected as the control and respectively analyzed the differences of CD34+ cell counts on the fifth and the sixth day in two groups. And the donors' adverse reaction to Plerixafor in the form of questionnaire was also observed. Then it was compared that the patients who underwent allo-HSCT in "G-CSF+Plerixafor" group and "G-CSF only" group in terms of acute GVHD at grade I-IV or III-IV, CMV reactivation and EBV reactivation.
RESULTS:
CD34+ cells count (M±Q) among PBSCs collected on the fifth and the sixth day in the observation group were (1.71±1.02)×106/kg and (4.23±2.33)×106/kg, respectively. CD34+ cell counts on the sixth day was significantly higher than that of the fifth day (P<0.001); While the counterparts in the control group were (2.47±1.60)×106/kg and (1.87±1.37)×106/kg, respectively. By statistical analysis, CD34+ cell counts on the sixth day was significantly less than that of the fifth day (P<0.001). The adverse reaction to Plerixafor for the donors in the study were all grade 1 or 2 (mild or moderate) according to CTCAE 5.0 and disappeared in a short time. The patients who underwent allo-HSCT in the "G-CSF+Plerixafor" group and "G-CSF only" group were not statistically significant in terms of acute GVHD at grade I-IV or III-IV, CMV reactivation and EBV reactivation (P>0.1).
CONCLUSION
The cell mobilization program of G-CSF combined with Plerixafor is safe and effective for being applied to allo-HSCT. The addition of Plerixafor can significantly increase the number of CD34 postive cells in the PBSC collection. Key words ; ;
Antigens, CD34
;
Benzylamines
;
Cyclams
;
Granulocyte Colony-Stimulating Factor
;
Hematopoietic Stem Cell Mobilization
;
Hematopoietic Stem Cell Transplantation
;
Hematopoietic Stem Cells
;
Heterocyclic Compounds
;
Humans
;
Peripheral Blood Stem Cell Transplantation
;
Retrospective Studies
9.Analysis of gene variation and clinical characteristics of Wiedemann-Steiner syndrome.
Ka CHEN ; Yu YANG ; Fi YANG ; Feng XIAO ; Xian WU ; Hui HUANG ; Xiang Yu XIONG ; Qiao SHI ; Xia SHUAI ; Li ZHOU
Chinese Journal of Pediatrics 2022;60(2):119-123
Objective: To summarize and analyze the clinical characteristics and gene mutations of 6 patients with Wiedemann-Steiner syndrome (WDSTS). Methods: To review and analyze the clinical data, including general conditions, clinical manifestations, growth hormone, cranial or pituitary gland magnetic resonance imaging (MRI),gene results and other data, 6 cases with WDSTS admitted to the Department of Endocrinology, Genetics and Metabolism of Jiangxi Provincial Children's Hospital and the Department of Child Care of Pingxiang Maternity and Child Care from April 2017 to February 2021 were recruited. Results: Of the 6 patients, 2 were male and 4 were female. The age of the first visit ranged from 1.0 to 11.2 years. All the 6 children presented with growth retardation and mental retardation and they all had typical facial dysmorphism and hypertrichosis (mainly on the back and limbs). Among them, case 5 had a growth hormone deficiency, and case 2 and 4 had abnormalities revealed by cranial MRI. Variations in KMT2A gene were identified in these 6 patients: c.10900+2T>C,c.10837C>T(p.Gln3613*), c.4332G>A(p.E1444E), c.2508dupC(p.W838Lfs*9), c.11695_11696delinsT(p.T3899Sfs*73), c.9915dupA (p.P3306Tfs*22).Among these variations, c.4332G>A, c.11695_11696delinsT and c.9915dupA were novel mutations. Therefore, the final diagnosis of these patients was WDSTS. Conclusions: Patients presented with short stature and mental retardation, typical facial dysmorphism and hypertrichosis should be considered WDSTS. Whole-exome sequencing plays an important role in disease diagnosis and genetic counseling.
Abnormalities, Multiple
;
Child
;
Child, Preschool
;
Craniofacial Abnormalities
;
Female
;
Growth Disorders/genetics*
;
Histone-Lysine N-Methyltransferase
;
Humans
;
Hypertrichosis/genetics*
;
Infant
;
Intellectual Disability/genetics*
;
Male
;
Myeloid-Lymphoid Leukemia Protein
;
Pregnancy
;
Syndrome

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