β-hydroxy-β-methylbutyric acid (HMB) is widely applied in sports nutrition, disease prevention and other fields. However, chemical synthesis methods, limited by toxic reagents and violent reactions, can hardly meet the demands of green production. The biosynthesis method mainly utilizes enzymatic catalysis or metabolic engineering techniques for synthesis, and has the advantages of high efficiency, low cost, and sustainability. Therefore, the production of HMB by the biosynthesis method has a good application prospect. In this research, a biosynthesis-based production strategy for HMB was developed. By using L-leucine as the substrate and constructing a dual-enzyme co-expression system, we established an efficient catalytic process. At first, the enzymatic properties of L-amino acid deaminase (PvL-AAD) from Proteus vulgaris and 4-hydroxyphenylpyruvate dioxygenase (Rn4-HPPD) from Rattus norvegicus were characterized. Rn4-HPPD had low relative activity and required an acidic environment for catalysis. Based on the surface charge modification strategy of the enzyme protein, site-directed mutagenesis and combinatorial mutagenesis were conducted on 10 sites of Rn4-HPPD. A double mutant Rn4-HPPD^H18R/N302R was thus obtained, with the enzyme activities being 2.00 times and 2.39 times that of the wild type at pH 5.5 and pH 6.5, respectively. Subsequently, the expression of the two enzymes in Escherichia coli was optimized. After the optimal expression ratio of the two enzymes was determined as 1:3 and under the conditions of OD₆₀₀ of 70, pH 6.0, 35 ℃, Fe²⁺ concentration of 1.5 mmol/L, and feeding of the substrate in batches in a 5 L fermenter, the maximum yield of HMB reached 8.60 g/L. This study not only enhances the optimal pH and activity of Rn4-HPPD but also provides new approaches for the efficient microbial synthesis of HMB.
Escherichia coli/metabolism* ; Valerates/metabolism* ; Recombinant Proteins/biosynthesis* ; Animals ; Metabolic Engineering/methods* ; Rats ; Catalysis

Premature ejaculation refers to a sexual dysfunction in which men experience a short intravaginal ejaculation latency and a lack of control over ejaculation during sexual activity. The onset of this condition is often accompanied by anxiety and depression, which can seriously affect the quality of the patient′s sexual life and the relationship between partners. Based on the "integration of body and spirit" theory in traditional Chinese medicine, our team believes that this condition is a comorbidity of physical and spiritual factors. We propose that the core pathogenesis of this disease lies in the "loss of form and essence, impairment of spirit, and depression of the mind, "while the primary treatment principle involves "nourishing form and regulating spirit." As a result, a new diagnosis and treatment approach of "four-dimensional integration" is summarized in this study. The disease is treated through the four dimensions of shape, body, spirit, and emotion. Traditional Chinese medicine is used to adjust the shape in cases where the physical form is damaged. For individuals with depression of heart and liver qi, the treatment focuses on soothing the heart and smoothing liver qi, and the modified Wangyou Powder and Xuanzhi Decoction is used. In cases where the heart and kidney function are compromised, the treatment involves nourishing both the heart and kidney while restoring interaction between the heart and the kidney, and modified Jihuo Yansi Elixir is used. To reduce the sensitivity of the glans penis, the patient′s body is washed with a traditional Chinese medicine formula, and a delicate fumigation formula is decocted for external washing. For those who are not in tune with their god, psychological counseling can be used to regulate their spirit and advocate "self-partner" and psychotherapy. If there are issues with intimacy, partners should focus on cooperating during foreplay, sexual intercourse, and post-coital interactions. Overall, the treatment aims to harmonize the body and spirit, addressing both physical and psychological factors through a comprehensive, multi-dimensional approach. This method provides new perspectives and ideas for the clinical diagnosis and treatment of this condition.

Chronic prostatitis,a common condition in andrology,is clinically characterized by a prolonged course,resistance to treatment,and frequent recurrence.In traditional Chinese medicine,it is classified under the categories of"turbid sperm,""overstrain strangury,"and"vaginal pain."Based on the"host-guest interaction-collateral disease"theory,we believe that healthy qi deficiency,latent pathogenic factors,and collateral obstruction are the primary pathological factors of this disease,which run through the entire process of chronic prostatitis occurrence and development.Accordingly,we propose that obstruction of collaterals and apathesia of the semen chamber are the core pathogenesis.The disease progression can be divided into three pathological stages:"deficiency,depression,and blood stasis."Spleen and kidney deficiency and malnutrition of collaterals form the pathological foundation.In the deficiency stage,treatment strategies involve reinforcing qi and nourishing the collaterals,using Fuzheng Yangrong Decoction.During disease progression,dampness and heat invasion,as well as collateral stagnation qi,are key contributors to disease progression.Thus,treatment focuses on clearing heat and dampness,promoting qi flow,and smoothing the collaterals,achieved with a modified Qiantongding Decoction.In the final stage,blood stasis and collateral obstruction dominate,warranting therapeutic strategies aimed at tonifying and removing blood stasis,addressing both the body and the collaterals simultaneously using the modified Guiling Huayu Decoction.Overall,the clinical treatment generally focuses on the concept of function through free flow,combination of unblocking and tonifying.This study provides a novel perspective and reference for clinical differentiation and treatment of chronic prostatitis.

Objective:To investigate the clinical characteristics of children with cervicothoracic hemivertebra at different ages and evaluate the surgical outcomes of hemivertebra resection.Methods:This retrospective cohort study analyzed clinical and radiographic data of 35 children (under 18 years old) with cervicothoracic hemivertebra who underwent one-stage posterior hemivertebra resection at the Department of Spine Surgery, Second Xiangya Hospital of Central South University, from June 2005 to June 2022. The cohort included 19 males and 16 females, with a surgical age of (9.7±4.1) years (range: 3 to <18 years). Patients were divided into three groups based on initial surgical age: preschool group (≤5 years, n=10), school-age group (6 to 10 years, n=10), and adolescent group (11 to <18 years, n=15). The intraoperative blood loss, operative time, number of fixed vertebrae, and perioperative and postoperative complications were recorded. Radiographic measurements were taken preoperatively, postoperatively, and at final follow-up, including the Cobb angle of the primary curve, curve length, distal curve Cobb angle, neck tilt, shoulder balance, coronal balance, trunk tilt, clavicle angle, head deviation, and local kyphosis. Statistical analyses included one-way ANOVA, Kruskal-Wallis H test, chi-square test, and Fisher′s exact test. Results:The operative time was (333±74) minutes (range:200 to 450 minutes), the intraoperative blood loss was (419±132) ml (range:200 to 650 ml), and the number of fixed vertebrae was (6.0±2.7) segments (range:2 to 12 segments). Preoperatively, the preschool group had a smaller primary curve Cobb angle compared to the adolescent group (33.6°±8.4° vs. 43.0°±9.4°, F=3.394, P=0.046) and distal curve Cobb angle (6.4°±2.4° vs.11.9°±4.5°, F=6.550, P=0.038). The preschool group had better coronal balance ((8.8±4.3) mm vs. (20.2±11.7)mm, F=9.448, P=0.009) and trunk tilt (4.0°±2.0° vs.7.0°±3.0°, F=4.343, P=0.029) than the school-age group. The preschool group had fewer fused vertebrae than the school-age and adolescent groups (3.8±1.6 vs. 7.0±2.6 vs. 6.8±2.6, F=10.480, P=0.005). The preschool group also had less intraoperative blood loss than the adolescent groups ((320±125) ml vs. (480±113) ml, F=8.666, P=0.013). However, no significant differences were found in postoperative and final follow-up measurements of primary and distal curve Cobb angles, neck tilt, shoulder balance, coronal balance, trunk tilt, clavicle angle, head deviation, local kyphosis, or complication rates (all P>0.05). Conclusions:Children with cervicothoracic hemivertebra across different age groups exhibit similar surgical outcomes and complication rates. But the preschool group had fewer fixed segments and less intraoperative blood loss, suggesting that this age group is an ideal time for surgery.

Objective To observe the clinical effect of doing Huatuo five-animal play treating blood-stasis-type silent myocardial ischemia(SMI)and its influence on coronary hemodynamics.Methods Ninety patients diagnosed as silent myocardial ischemia were randomly divided into a five-animal play group(n=45,age:51.56±11.00 years,24 males and 21 females)and a regular exercise group(n=45,age:52.44±7.19 years old,24 males and 21 females)according to a random number table.The five-animal play group practised the traditional five-animal play,while the regular exercise group con-ducted daily 30-minute moderate-intensity treadmill aerobic exercise,five times a week,for 4 weeks.The changes in the number of abnormal ST-T segment occurrences,myocardial oxygen consumption(CMO),coronary ischemia threshold(CIT),and blood smoothness index(BSD)within 24-hour ambu-latory electrocardiogram before and after the intervention were observed in both groups,with the thera-peutic effect and hemodynamic characteristics of both groups evaluated.Results The average number of ST-T segment abnormalities decreased after intervention in both groups(P<0.001),with significantly greater improvement in the five-animal play group than the regular exercise group(P<0.001).More-over,the average CMO decreased significantly,while the average CMR and BSD increased significant-ly in both groups after intervention(P<0.05),with significantly greater improvement in the five-ani-mal play group than the other group.Meanwhile,the total effective rate in the five-animal play group was significantly higher than the regular exercise group(P<0.01).Conclusion Undergoing the five-ani-mal play and moderate intensity treadmill aerobic exercise both are effective in treating silent myocardi-al ischemia.However,the former therapy is superior to the latter in bettering CMO,CIT and BSD.

Objective: To explore the influencing factors and pathways of suicidal ideation among children and adolescents with severe autism spectrum disorder (ASD), so as to provide references for clarifying the impact intensity and pathways of various factors on suicidal ideation in the population. Methods: A cross sectional study was conducted from June 17, 2024, to January 12, 2025, involving 96 severely affected ASD children and adolescents aged 8-18 years from Tianjin. Participants were assessed using the Puberty Development Scale (PDS), Children s Alexithymia Measure (CAM), Strengths and Difficulties Questionnaire (SDQ), and Positive and Negative Suicide Ideation (PANSI). The random forest Boruta algorithm was employed to screen core variables, and a Bayesian network model was constructed to analyze the influencing factors of suicidal ideation in children and adolescents with severe ASD. Results: Through the screening using the Boruta algorithm, the SDQ scale score, conduct problems, hyperactivity, peer relationship problems and prosocial behavior were identified as the key predictors of suicidal ideation. A Bayesian network model was established with hyperactivity as the central mediating node. The impact of hyperactivity on suicidal ideation exhibited a non linear relationship: compared to the normal state (31.6%, 68.4%), the borderline state of hyperactivity was associated with a higher probability of low risk suicidal ideation (47.1%) and a lower probability of high risk suicidal ideation (52.9%). Suicidal ideation among children and adolescents with severe ASD was closely related to hyperactivity. In the state of hyperactivity, the abnormal peer relationship (95.2%) and the abnormal prosocial behavior (77.0%) were aggravated. Conclusions Suicide ideation among children and adolescents with severe ASD is strongly associated with hyperactivity traits. It is necessary to establish a prevention and control system centered on hyperactivity intervention to reduce this risk.

Objective To observe the clinical effect of doing Huatuo five-animal play treating blood-stasis-type silent myocardial ischemia(SMI)and its influence on coronary hemodynamics.Methods Ninety patients diagnosed as silent myocardial ischemia were randomly divided into a five-animal play group(n=45,age:51.56±11.00 years,24 males and 21 females)and a regular exercise group(n=45,age:52.44±7.19 years old,24 males and 21 females)according to a random number table.The five-animal play group practised the traditional five-animal play,while the regular exercise group con-ducted daily 30-minute moderate-intensity treadmill aerobic exercise,five times a week,for 4 weeks.The changes in the number of abnormal ST-T segment occurrences,myocardial oxygen consumption(CMO),coronary ischemia threshold(CIT),and blood smoothness index(BSD)within 24-hour ambu-latory electrocardiogram before and after the intervention were observed in both groups,with the thera-peutic effect and hemodynamic characteristics of both groups evaluated.Results The average number of ST-T segment abnormalities decreased after intervention in both groups(P<0.001),with significantly greater improvement in the five-animal play group than the regular exercise group(P<0.001).More-over,the average CMO decreased significantly,while the average CMR and BSD increased significant-ly in both groups after intervention(P<0.05),with significantly greater improvement in the five-ani-mal play group than the other group.Meanwhile,the total effective rate in the five-animal play group was significantly higher than the regular exercise group(P<0.01).Conclusion Undergoing the five-ani-mal play and moderate intensity treadmill aerobic exercise both are effective in treating silent myocardi-al ischemia.However,the former therapy is superior to the latter in bettering CMO,CIT and BSD.

Chronic prostatitis,a common condition in andrology,is clinically characterized by a prolonged course,resistance to treatment,and frequent recurrence.In traditional Chinese medicine,it is classified under the categories of"turbid sperm,""overstrain strangury,"and"vaginal pain."Based on the"host-guest interaction-collateral disease"theory,we believe that healthy qi deficiency,latent pathogenic factors,and collateral obstruction are the primary pathological factors of this disease,which run through the entire process of chronic prostatitis occurrence and development.Accordingly,we propose that obstruction of collaterals and apathesia of the semen chamber are the core pathogenesis.The disease progression can be divided into three pathological stages:"deficiency,depression,and blood stasis."Spleen and kidney deficiency and malnutrition of collaterals form the pathological foundation.In the deficiency stage,treatment strategies involve reinforcing qi and nourishing the collaterals,using Fuzheng Yangrong Decoction.During disease progression,dampness and heat invasion,as well as collateral stagnation qi,are key contributors to disease progression.Thus,treatment focuses on clearing heat and dampness,promoting qi flow,and smoothing the collaterals,achieved with a modified Qiantongding Decoction.In the final stage,blood stasis and collateral obstruction dominate,warranting therapeutic strategies aimed at tonifying and removing blood stasis,addressing both the body and the collaterals simultaneously using the modified Guiling Huayu Decoction.Overall,the clinical treatment generally focuses on the concept of function through free flow,combination of unblocking and tonifying.This study provides a novel perspective and reference for clinical differentiation and treatment of chronic prostatitis.

Objective:To investigate the clinical characteristics of children with cervicothoracic hemivertebra at different ages and evaluate the surgical outcomes of hemivertebra resection.Methods:This retrospective cohort study analyzed clinical and radiographic data of 35 children (under 18 years old) with cervicothoracic hemivertebra who underwent one-stage posterior hemivertebra resection at the Department of Spine Surgery, Second Xiangya Hospital of Central South University, from June 2005 to June 2022. The cohort included 19 males and 16 females, with a surgical age of (9.7±4.1) years (range: 3 to <18 years). Patients were divided into three groups based on initial surgical age: preschool group (≤5 years, n=10), school-age group (6 to 10 years, n=10), and adolescent group (11 to <18 years, n=15). The intraoperative blood loss, operative time, number of fixed vertebrae, and perioperative and postoperative complications were recorded. Radiographic measurements were taken preoperatively, postoperatively, and at final follow-up, including the Cobb angle of the primary curve, curve length, distal curve Cobb angle, neck tilt, shoulder balance, coronal balance, trunk tilt, clavicle angle, head deviation, and local kyphosis. Statistical analyses included one-way ANOVA, Kruskal-Wallis H test, chi-square test, and Fisher′s exact test. Results:The operative time was (333±74) minutes (range:200 to 450 minutes), the intraoperative blood loss was (419±132) ml (range:200 to 650 ml), and the number of fixed vertebrae was (6.0±2.7) segments (range:2 to 12 segments). Preoperatively, the preschool group had a smaller primary curve Cobb angle compared to the adolescent group (33.6°±8.4° vs. 43.0°±9.4°, F=3.394, P=0.046) and distal curve Cobb angle (6.4°±2.4° vs.11.9°±4.5°, F=6.550, P=0.038). The preschool group had better coronal balance ((8.8±4.3) mm vs. (20.2±11.7)mm, F=9.448, P=0.009) and trunk tilt (4.0°±2.0° vs.7.0°±3.0°, F=4.343, P=0.029) than the school-age group. The preschool group had fewer fused vertebrae than the school-age and adolescent groups (3.8±1.6 vs. 7.0±2.6 vs. 6.8±2.6, F=10.480, P=0.005). The preschool group also had less intraoperative blood loss than the adolescent groups ((320±125) ml vs. (480±113) ml, F=8.666, P=0.013). However, no significant differences were found in postoperative and final follow-up measurements of primary and distal curve Cobb angles, neck tilt, shoulder balance, coronal balance, trunk tilt, clavicle angle, head deviation, local kyphosis, or complication rates (all P>0.05). Conclusions:Children with cervicothoracic hemivertebra across different age groups exhibit similar surgical outcomes and complication rates. But the preschool group had fewer fixed segments and less intraoperative blood loss, suggesting that this age group is an ideal time for surgery.