2.Rational design of L-arabinose isomerase from Lactobacillus fermentum and its application in D-tagatose production.
Juan LI ; Jing WU ; Sheng CHEN ; Wei XIA
Chinese Journal of Biotechnology 2023;39(3):1107-1118
L-arabinose isomerase (L-AI) is the key enzyme that isomerizes D-galactose to D-tagatose. In this study, to improve the activity of L-arabinose isomerase on D-galactose and its conversion rate in biotransformation, an L-arabinose isomerase from Lactobacillus fermentum CGMCC2921 was recombinantly expressed and applied in biotransformation. Moreover, its substrate binding pocket was rationally designed to improve the affinity and catalytic activity on D-galactose. We show that the conversion of D-galactose by variant F279I was increased 1.4 times that of the wild-type enzyme. The Km and kcat values of the double mutant M185A/F279I obtained by superimposed mutation were 530.8 mmol/L and 19.9 s-1, respectively, and the catalytic efficiency was increased 8.2 times that of the wild type. When 400 g/L lactose was used as the substrate, the conversion rate of M185A/F279I reached a high level of 22.8%, which shows great application potential for the enzymatic production of tagatose from lactose.
Galactose/metabolism*
;
Limosilactobacillus fermentum/genetics*
;
Lactose
;
Hexoses/metabolism*
;
Aldose-Ketose Isomerases/genetics*
;
Hydrogen-Ion Concentration
3.Recent research on neurodevelopmental disorders in children.
Hong-Min ZHU ; Chun-Hui YUAN ; Zhi-Sheng LIU
Chinese Journal of Contemporary Pediatrics 2023;25(1):91-97
Neurodevelopmental disorders (NDDs) in children are a group of chronic developmental brain disorders caused by multiple genetic or acquired causes, including disorders of intellectual development, developmental speech or language disorders, autism spectrum disorders, developmental learning disorders, attention deficit hyperactivity disorder, tic disorders, and other neurodevelopmental disorders. With the improvement in the research level and the diagnosis and treatment techniques of NDDs, great progress has been made in the research on NDDs in children. This article reviews the research advances in NDDs, in order to further improve the breadth and depth of the understanding of NDDs in children among pediatricians.
Humans
;
Child
;
Neurodevelopmental Disorders/therapy*
;
Autism Spectrum Disorder/therapy*
;
Attention Deficit Disorder with Hyperactivity
4.A precision medication study of atomoxetine in children with attention deficit hyperactivity disorder: CYP2D6 genetic testing and therapeutic drug monitoring.
Di FU ; Hong-Li GUO ; Ya-Hui HU ; Feng CHEN
Chinese Journal of Contemporary Pediatrics 2023;25(1):98-103
Atomoxetine is the first non-stimulant drug for the treatment of children and adults with attention deficit hyperactivity disorder (ADHD), and its safety and efficacy show significant differences in the pediatric population. This article reviews the genetic factors influencing the pharmacokinetic differences of atomoxetine from the aspect of the gene polymorphisms of the major metabolizing enzyme CYP2D6 of atomoxetine, and then from the perspective of therapeutic drug monitoring, this article summarizes the reference ranges of the effective concentration of atomoxetine in children with ADHD proposed by several studies. In general, there is an association between the peak plasma concentration of atomoxetine and clinical efficacy, but with a lack of data from the Chinese pediatric population. Therefore, it is necessary to establish related clinical indicators for atomoxetine exposure, define the therapeutic exposure range of children with ADHD in China, and combine CYP2D6 genotyping to provide support for the precision medication of atomoxetine.
Adult
;
Child
;
Humans
;
Adrenergic Uptake Inhibitors/therapeutic use*
;
Atomoxetine Hydrochloride/therapeutic use*
;
Attention Deficit Disorder with Hyperactivity/genetics*
;
Cytochrome P-450 CYP2D6/therapeutic use*
;
Drug Monitoring
;
Genetic Testing
;
Propylamines/therapeutic use*
;
Treatment Outcome
5.The mediating role of emotion regulation strategies between symptoms and anxiety problems in children with attention deficit hyperactivity disorder.
Lin ZHONG ; Jing ZHANG ; Peng-Xiang ZUO
Chinese Journal of Contemporary Pediatrics 2023;25(3):259-264
OBJECTIVES:
To study the mediating role of emotion regulation strategies between symptoms and anxiety problems in children with attention deficit hyperactivity disorder (ADHD).
METHODS:
Convenience cluster sampling was performed to select 435 eligible children with ADHD from 10 211 students in 10 elementary schools in Kashgar of Xinjiang Uygur Autonomous Region. SNAP-IV Assessment Scale, Emotion Regulation Questionnaire for Children and Adolescents, and Conners Parent Symptoms Questionnaire were used to obtain relevant information. The Spearman correlation analysis and the moderated mediation method were used for data analysis.
RESULTS:
For the children with ADHD, the score of cognitive reappraisal was negatively correlated with the scores of symptoms and anxiety problems (rs=-0.254 and -0.270 respectively, P<0.001), and the score of symptoms was positively correlated with the score of anxiety problems (rs=0.329, P<0.001). The analysis of mediating effect showed that cognitive reappraisal played a partial mediating role between symptoms and anxiety problems, with a 95% confidence interval of 0.008-0.027, and the mediating effect accounted for 16.10% of the total effect. In addition, sex played a regulatory role in this mediation model (P<0.001).
CONCLUSIONS
Cognitive reappraisal plays a mediating role between symptoms and anxiety problems in children with ADHD, while sex regulates the relationship of symptoms with cognitive reappraisal and anxiety problems in these children.
Adolescent
;
Humans
;
Child
;
Attention Deficit Disorder with Hyperactivity
;
Emotional Regulation
;
Anxiety
;
Anxiety Disorders
;
Surveys and Questionnaires
6.Effect of pH on the chelation between strontium ions and decellularized small intestinal submucosal sponge scaffolds.
Yu Ke LI ; Mei WANG ; Lin TANG ; Yu Hua LIU ; Xiao Ying CHEN
Journal of Peking University(Health Sciences) 2023;55(1):44-51
OBJECTIVE:
To investigate the preparation of decellularized small intestinal submucosa (dSIS) sponge scaffolds with chelated strontium (Sr) ions at different pH values, and to select the appropriate pH values for synthesizing Sr/dSIS scaffolds using the physicochemical properties and biocompatibility of the scaffolds as evaluation indexes.
METHODS:
(1) Sr/dSIS scaffolds preparation and grouping: After mixing dSIS solution and strontium chloride solution in equal volumes, adjusting pH of the solution to 3, 5, 7, and 9 respectively, porous scaffolds were prepared by freeze-drying method after full reaction at 37℃, which were named Sr/dSIS-3, -5, -7, and -9 respectively, and the dSIS scaffolds were used as the control group. (2) Physicochemical property evaluation: The bulk morphology of the scaffolds was observed in each group, the microscopic morphology analyzed by scanning electron microscopy, and the porosity and pore size determined, the surface elements analyzed by energy spectroscopy, the structure of functional groups analyzed by infrared spectroscopy, the chelation rate determined by atomic spectrophotometry, the water absorption rate detected by using specific gravity method, and the compression strength evaluated by universal mechanical testing machine.(3) Biocompatibility evaluation: The cytotoxicity and proliferative effect to bone mesenchymal stem cells (BMSCs) of each group were evaluated by Calcein-AM/PI double staining method.
RESULTS:
Scanning electron microscopy showed that the scaffolds of each group had an interconnected three-dimensional porous structure with no statistical difference in pore size and porosity. Energy spectrum analysis showed that strontium could be detected in Sr/dSIS-5, -7 and -9 groups, and strontium was uniformly distributed in the scaffolds. Functional group analysis further supported the formation of chelates in the Sr/dSIS-5, -7 and -9 groups. Chelation rate analysis showed that the Sr/dSIS-7 group had the highest strontium chelation rate, which was statistically different from the other groups (P < 0.05). The scaffolds in all the groups had good water absorption. The scaffolds in Sr/dSIS-5, -7 and -9 groups showed significantly improved mechanical properties compared with the control group (P < 0.05). The scaffolds in all the groups had good biocompatibility, and the Sr/dSIS-7 group showed the best proliferation of BMSCs.
CONCLUSION
When pH was 7, the Sr/dSIS scaffolds showed the highest strontium chelation rate and the best proliferation effect of BMSCs, which was the ideal pH value for the preparation of the Sr/dSIS scaffolds.
Tissue Scaffolds/chemistry*
;
Biocompatible Materials
;
Strontium/pharmacology*
;
Ions
;
Hydrogen-Ion Concentration
;
Tissue Engineering/methods*
;
Porosity
7.Physical growth and dietary characteristics of children with attention deficit hyperactivity disorder: a cross-sectional study.
Shuang LIN ; Dan-Dan WU ; Shu-Jin CHEN ; Wu YAN ; Li-Hua DOU ; Xiao-Nan LI
Chinese Journal of Contemporary Pediatrics 2023;25(7):711-717
OBJECTIVES:
To investigate the physical growth and dietary characteristics of children with attention deficit hyperactivity disorder (ADHD), and to analyze their relationship with core symptoms of ADHD.
METHODS:
A total of 268 children who were newly diagnosed with ADHD in Children's Hospital of Nanjing Medical University from June to December 2020 were included in the ADHD group, and 102 healthy children who underwent physical examination during the same period were selected as the control group. Physical evaluations and dietary surveys were conducted for both groups. ADHD diagnosis and scoring were performed according to the Diagnostic and Statistical Manual of Mental Disorders (5th edition). Factor analysis, Spearman correlation analysis, and mediation analysis were used to study the relationship between core symptoms of ADHD, dietary patterns, and physical growth.
RESULTS:
The rate of overweight/obesity in the ADHD group was significantly higher than that in the control group (35.8% vs 21.6%, P<0.05). Three dietary patterns were extracted from the food frequency questionnaire: vegetarian dietary pattern, traditional dietary pattern, and snack/fast food pattern. The factor score for the snack/fast food pattern in the ADHD group was higher than that in the control group (P<0.05). There was a significant positive correlation between ADHD symptom scores, snack/fast food pattern factor scores, and body fat percentage (P<0.05). The mediation analysis showed that the snack/fast food pattern played a partial mediating role in the relationship between ADHD symptom scores and body fat percentage, with a mediation proportion of 26.66%.
CONCLUSIONS
The rate of overweight/obesity in children with ADHD is higher than that in non-ADHD children. Core symptoms of ADHD are related to dietary patterns and physical growth, with the snack/fast food pattern playing a partial mediating role in the relationship between core symptoms of ADHD and physical growth.
Humans
;
Child
;
Attention Deficit Disorder with Hyperactivity/epidemiology*
;
Cross-Sectional Studies
;
Overweight
;
Pediatric Obesity
;
Diet
9.Progress in neural network mechanism of tinnitus using functional magnetic resonance imaging.
Kehui REN ; Hui LIU ; Yujuan WANG ; Wen ZHANG ; Ting YANG ; Lili XU
Journal of Clinical Otorhinolaryngology Head and Neck Surgery 2023;37(7):582-587
Tinnitus refers to the perception of abnormal sound in the absence of external sound stimulation. It can have an impact on a person's mood, memory, attention, and mental state, although the mechanism of tinnitus is still unclear. In recent years, the research on the central neural mechanism of tinnitus has attracted the attention of scholars.Functional magnetic resonance imaging (fMRI),as an effective imaging technology, has been actively employed in this field. This paper provides a systematic summary of studies on the central neural mechanism of tinnitus by fMRI in recent years,revealed the changes of functional connections among tinnitus-related neural networks,such as auditory network,limbic system,default mode network and salience network. The central neural mechanism of tinnitus involves multiple networks that interact with each other. By understanding this mechanism, we hope to develop more targeted prevention and treatment strategies to help patients alleviate long-term tinnitus.
Humans
;
Tinnitus/diagnostic imaging*
;
Magnetic Resonance Imaging/methods*
;
Attention

Result Analysis
Print
Save
E-mail