BACKGROUND: The mechanisms distinguishing metabolically healthy from unhealthy phenotypes within the same BMI categories remain unclear. This study aimed to investigate the associations between regional fat distribution and metabolically unhealthy phenotypes in Chinese adults across different BMI categories. METHODS: This cross-sectional study involving 11833 Chinese adults aged 20 years and older. Covariance analysis, adjusted for age, compared the percentage of regional fat (trunk, leg, or arm fat divided by whole-body fat) between metabolically healthy and unhealthy participants. Trends in regional fat percentage with the number of metabolic abnormalities were assessed by the Jonckheere-Terpstra test. Odds ratios (ORs) and their 95% confidence intervals (CIs) were estimated by logistic regression models. All analyses were performed separately by sex. RESULTS: In non-obese individuals, metabolically unhealthy participants exhibited higher percent trunk fat and lower percent leg fat compared to healthy participants. Additionally, percent trunk fat increased and percent leg fat decreased with the number of metabolic abnormalities. After adjustment for demographic and lifestyle factors, as well as BMI, higher percent trunk fat was associated with increased odds of being metabolically unhealthy [highest vs. lowest quartile: ORs (95%CI) of 1.64 (1.35, 2.00) for men and 2.00 (1.63, 2.46) for women]. Conversely, compared with the lowest quartile, the ORs (95%CI) of metabolically unhealthy phenotype in the highest quartile for percent arm and leg fat were 0.64 (0.53, 0.78) and 0.60 (0.49, 0.74) for men, and 0.72 (0.56, 0.93) and 0.46 (0.36, 0.59) for women, respectively. Significant interactions between BMI and percentage of trunk and leg fat were observed in both sexes, with stronger associations found in individuals with normal weight and overweight. CONCLUSIONS Trunk fat is associated with a higher risk of metabolically unhealthy phenotype, while leg and arm fat are protective factors. Regional fat distribution assessments are crucial for identifying metabolically unhealthy phenotypes, particularly in non-obese individuals.
Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Young Adult ; Adipose Tissue ; Body Fat Distribution ; Body Mass Index ; China/epidemiology* ; Cross-Sectional Studies ; Health Surveys ; Phenotype

The importance of gait assessment in the rehabilitation of cancer patients is gradually being recognized. However, quantitative analysis of balance ability in cancer patients is still limited. A total of 102 cancer patients meeting the inclusion criteria were recruited from Hefei Cancer Hospital, Chinese Academy of Sciences. Their balance ability was evaluated using the Berg Balance Scale (BBS). Gait data were collected by an electronic walkway and an IMU sensor system, including spatial-temporal and kinematic gait features such as step length, cadence, support time, and range of motion. Recursive feature elimination was used for feature selection. Ridge, Elastic Net, SVR, RF, and AdaBoost models were used to predict balance ability scores. Five-fold cross-validation was used to evaluate the performance of these models. Results show that the SVR model achieves the best performance with fifteen features (RMSE=3.22, R ²=0.91), followed by Ridge (RMSE=3.63, R ²=0.89). A method for evaluating balance ability based on gait features is proposed, providing a quantitative tool for personalized rehabilitation interventions in cancer patients.
Humans ; Postural Balance ; Neoplasms/rehabilitation* ; Gait ; Gait Analysis ; Biomechanical Phenomena ; Female

OBJECTIVES: To explore the value of serum cystatin C (CysC) levels in evaluating renal prognosis in IgA nephropathy (IgAN) patients. METHODS: We retrospectively collected the clinical data of IgAN patients diagnosed by renal biopsy at Guangdong Provincial People's Hospital from January, 2014 to December, 2018. Based on baseline serum CysC levels, the patients were divided into high serum CysC (>1.03 mg/L) group and normal serum CysC (≤1.03 mg/L) group. The composite endpoint for poor renal prognosis was defined as ≥50% decline in estimated glomerular filtration rate (eGFR) and/or progression to end-stage renal disease (ESRD). Lasso regression, multivariate Cox regression and Kaplan-Meier survival analysis were used to identify the risk factors and compare renal survival rates between the two groups. Smooth curves fitting and threshold effect analysis were used to explore the relationship between serum CysC levels and the outcomes. A nomogram model was constructed and its predictive performance was evaluated using concordance index, calibration curve, receiver operating characteristic (ROC) curve and the area under curve (AUC). RESULTS: A total of 356 IgAN patients were enrolled, who were followed up for 4.65±0.93 years. The composite endpoint occurred in 74 patients. High serum CysC was identified as an independent risk factor for poor renal prognosis in IgAN (HR=2.142, 95% CI 1.222 to 3.755), and the patients with high serum CysC levels had a lower renal survival rate (Log-rank χ²=47.970, P<0.001). In patients with serum CysC below 2.12 mg/L, a higher CysC level was associated with an increased risk of poor renal prognosis (β=3.487, 95% CI: 2.561-4.413, P<0.001), while above this level, the increase of the risk was not significant (β=0.676, 95% CI: -0.642-1.995, P=0.315). The nomogram model based on serum CysC and 3 other independent risk factors demonstrated good internal validity with a concordance index of 0.873 (95% CI: 0.839-0.907) and an AUC of 0.909 (95% CI: 0.873-0.945). CONCLUSIONS Serum CysC levels are associated with renal prognosis in IgAN patients, and high serum CysC an independent risk factor for poor renal prognosis.
Humans ; Glomerulonephritis, IGA/diagnosis* ; Cystatin C/blood* ; Prognosis ; Risk Factors ; Retrospective Studies ; Glomerular Filtration Rate ; Kidney Failure, Chronic ; Male ; Female ; Adult ; Nomograms ; Middle Aged

L-theanine is an important natural non-protein amino acid that is widely used in food and medicine. Although in previous studies, a microbial fermentation method for L-theanine without the addition of ethylamine has been developed, the conversion rate of this process needs to be further improved. In this study, we constructed a de novo synthesis pathway of L-theanine with glucose as the substrate. First, an in vitro transformation pathway containing ω-transaminase (TA) and γ-glutamylmethylamide synthetase (GMAS) was designed, optimized, and introduced into the chassis strain Escherichia coli K12 W3110 to achieve de novo synthesis of L-theanine. To improve the synthesis efficiency through metabolic engineering, we increased the copies of the GMAS gene gams and the TA gene spuC and enhanced the expression of the aldehyde dehydrogenase gene eutE to provide sufficient acetaldehyde substrate, knocked out the lactate dehydrogenase gene ldhA and the pyruvate formate lyase gene pflB to block bypass metabolism, and introduced the alanine dehydrogenase gene alD to recycle alanine. Furthermore, we over-expressed the phosphoenolpyruvate carboxylase gene ppc to enhance the carbon flux of the TCA cycle, knocked out the succinyl-CoA synthase gene sucCD to reduce the loss of downstream flux of TCA, and integrated the glutamate dehydrogenase gene gdh to enhance the supply of L-glutamate. Finally, the polyphosphate kinase gene ppk was introduced to the ATP cycle, which enhanced the energy supply in L-theanine production. The recombinant strain Tea11 produced 22.60 g/L L-theanine in a 5 L fermenter in 28 h, with a conversion rate of 41.71%. This synthetic pathway in this study balanced the relationship between the supply of ethylamine and the production of theanine, providing a new idea for metabolic engineering of microorganisms to produce L-theanine.
Glutamates/biosynthesis* ; Metabolic Engineering/methods* ; Escherichia coli/genetics* ; Fermentation ; Transaminases/metabolism* ; Amide Synthases/metabolism* ; Glucose/metabolism*

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

L-tyrosine is one of the 20 amino acids that make up proteins and is an essential amino acid for mammals, often used as a nutritional supplement. The conventional methods for synthesizing L-tyrosine have some problems such as the production of many by-products, high requirements for production conditions, and environmental pollution. In this study, we designed and constructed a multi-enzyme cascade for the synthesis of L-tyrosine with alanine, glutamate, ammonium chloride, and phenol as substrates. Initially, the sources of glutamate oxidase, alanine aminotransferase, and tyrosine phenol lyase were screened and analyzed, which was followed by the identification of the rate-limiting enzyme in the reaction process. A colorimetric screening method was established, and the rate-limiting enzyme DbAlaA was engineered to enhance its activity by 40.0%. Subsequently, the reaction conditions, including temperature, pH, cell concentration, and surfactant and coenzyme dosages, were optimized. After optimization, the yield of L-tyrosine reached 9.93 g/L, with a alanine conversion rate of 54.90%. Finally, a feed-batch fermentation strategy was adopted, and the yield of L-tyrosine reached 56.07 g/L after 24 h, with a alanine conversion rate of 65.22%. This study provides a reference for the whole-cell catalytic synthesis of L-tyrosine and its industrialization.
Tyrosine/biosynthesis* ; Escherichia coli/metabolism* ; Tyrosine Phenol-Lyase/genetics* ; Multienzyme Complexes/metabolism* ; Fermentation

Objective To conduct preliminary evaluation of the reliability and safety of pancreatic duct-to-jejunum stent-bridging internal drainage as a supplementary approach to pancreaticojejunostomy in central pancreatectomy.Methods The clinical data of 28 patients who underwent robotic central pancreatectomy performed by our team between January 2021 and November 2024 were retrospectively collected,and and follow-up of postoperative endocrine and exocrine functions was performed.Based on the methods of digestive tract reconstruction adopted,the patients were divided into a conventional pancreaticojejunostomy group and a pancreatic duct-to-jejunum stent-bridging internal drainage group(PancreaticoJejunal-Stent bridge group).The operative time,digestive tract reconstruction time,and short-term complications were compared between the two groups.Results Among patients undergoing robotic central pancreatectomy,the digestive tract reconstruction time was shorter(t=5.168,P<0.001)in the PancreaticoJejunal-Stent bridge group([31.1±6.3]min)than that in the conventional pancreaticojejunostomy group([49.7±8.9]min)(t=5.168,P<0.001).The total operative time was(172.7±64.6)min in the PancreaticoJejunal-Stent bridge group and(200.1±52.7)min in the conventional pancreaticojejunostomy group,showing no statistically significant difference(t=1.215,P=0.235).In the PancreaticoJejunal-Stent bridge group,one patient developed a postoperative biochemical fistula,and 14 patients developed grade B pancreatic fistulas.Among the 14 patients with grade B pancreatic fistulas,1 case was complicated by fistula-related intra-abdominal infection,and 13 cases had drainage tube retention time of more than 21 days.In the conventional pancreaticojejunostomy group,2 patients developed postoperative biochemical fistulas,and 11 patients developed grade B pancreatic fistulas.Among the 11 patients with grade B pancreatic fistulas,1 case was complicated by fistula-related intra-abdominal infection,and 1 case was complicated by fistula-related intra-abdominal bleeding and infection.No postoperative gastroparesis,pancreatitis,or grade C pancreatic fistulas occurred in either group.There were no statistically significant differences between the two groups in overall postoperative complication rate(P=0.522),postoperative pancreatic fistula rate(P=0.583),intra-abdominal infection rate(P=0.583),or bleeding rate(P=0.464).Conclusion Pancreatic duct-to-jejunum stent-bridging internal drainage optimizes the anastomosis between the distal end of the pancreas and the jejunum during central pancreatectomy,shortens digestive tract reconstruction time,and reduces surgical complexity without increasing the risk of short-term severe postoperative complications.This approach is safe and feasible.

As an intermediate phenotype for multiple cardiovascular diseases, left ventricular hypertrophy (LVH) benefits from early diagnosis, which allows for timely intervention to prevent worsening of the condition, mitigate severe complications like heart failure and arrhythmias, and consequently improve patient outcomes. Preliminary advances have been made using deep learning for the early diagnosis and identification of etiology in LVH. This paper reviews the pathophysiology, causes, and diagnostic standards for LVH, discusses the strengths and weaknesses of applying deep learning to diagnostic tools such as echocardiography, cardiac magnetic resonance imaging, and electrocardiogram, examines its use in prognostic evaluation, and concludes by summarizing current achievements and suggesting future research avenues.

Shear thinning is an ideal feature of bioink because it can reduce the chance of blocking. For extrusion based biological printing, bioink will experience shear force when passing through the biological printer. The shear rate will increase with the increase of extrusion rate, and the apparent viscosity of shear-thinning bioink will decrease, which makes it easier to block, thus achieving the structural fidelity of 3D printing tissue. The manufacturing of complex functional structures in tissue trachea requires the precise placement and coagulation of bioink layer by layer, and the shear-thinning bioink may well meet this requirement. This review focuses on the importance of mechanical properties, classification and preparation methods of shear-thinning bioink, and lists its current application status in 3D printing tissue trachea to discuss the more possibilities and prospects of this biological material in tissue trachea.