ObjectiveTo prepare a recombinant PETase with a dual-catalytic-triad and to evaluate its efficiency in the biodegradation of polyethylene terephthalate （PET）. MethodsBased on the crystal structure of wild-type PETase， point mutations （T88H/L117D） were introduced via site-directed mutagenesis. The recombinant protein was prepared using prokaryotic expression and chromatography purification techniques. The enzymatic hydrolysis of the mutant PETase was assessed by relatively quantifying the products mono （2-hydroxyethyl） terephthalate （MHET） and terephthalic acid （TPA）. ResultsBoth wild-type and mutant PETases accumulated as inclusion bodies， accounting for approximately 20% of the total bacterial protein. After solubilization in urea， the proteins were eluted at 300 mmol/L imidazole during affinity chromatography purification， with concentrations of 1.824 and 1.833 mg/mL and purities of 83.11% and 84.32%， respectively. Subsequent anion-exchange chromatography yielded highly pure enzymes in the 200 mmol/L NaCl fraction： 2.776 mg/mL （96.86% purity） for the wild type and 1.967 mg/mL （95.13% purity） for the mutant. Following refolding， the final concentrations were 0.484 mg/mL for the wild type and 0.991 mg/mL for the mutant. Hydrolysis assays revealed that the mutant released MHET and TPA at （237.67±17.00）% and （197.33±12.01）% of the wild-type levels， respectively. ConclusionThe T88H/L117D dual-catalytic-triad PETase is successfully prepared and it significantly enhanced PET-degrading activity， thus， it′s a promising biocatalyst for PET bioremediation.

Objective To investigate the effects of Mawangdui exercise combined with neuro-muscular electrical stimulation(NMES)on pulmonary function,exercise capacity and quality of life in patients with chronic obstructive pulmonary disease(COPD).Methods A total of 96 COPD pa-tients were selected as the study subjects,and divided into control group(n=48)and intervention group(n=48).The control group received conventional pharmacological treatment,while the inter-vention group received Mawangdui exercise combined with NMES in addition to conventional pharma-cological treatment.The ratio of forced expiratory volume in the first second(FEV1)to forced vital capacity(FVC)(FEV1/FVC),the percentage of predicted FEV,(FEV1％),respiratory rate,re-sults of the 6-minute walk test(6MWT),scores of COPD Assessment Test(CAT),St.George's Respira-tory Questionnaire-I(SGRQ-I),Hospital Anxiety and Depression Scale(HADS)and Borg CR-10 Scale were analyzed in both groups before and after treatment.Results After 1 and 3 months of treatment,significant differences were observed in respiratory rate and 6MWT results between the two groups(P＜0.05).After 1 and 3 months of treatment,the FEV1％and FEV1/FVC in the intervention group were significantly higher than those at admission,and the FEV1％and FEV1/FVC after 3 months of treatment were significantly higher than those after 1 month of treatment(P＜0.05).Af-ter 3 months oftreatment,a significant difference in FEV1/FVC was observed between the two groups(P＜0.05).After 3 months of treatment,the CAT and SGRQ-I scores in the intervention group were significantly lower than those at admission(P＜0.05).After 3 months of treatment,the Borg CR-10 Scale score in the intervention group was significantly lowerthan that at admission and after 1 month of treatment(P＜0.05).After 3 months of treatment,a significant difference in SGRQ-I scores was observed between the two groups(P＜0.05).After 1 and 3 months of treatment,the HADS scores in the intervention group were significantly lower than those at admission,and the HADS score after 3 months of treatment was significantly lower than that after 1 month of treatment(P＜0.05).After 1 and 3 months of treatment,significant differences in HADS scores were ob-served between the two groups(P＜0.05).Conclusion Mawangdui exercise combined with NMES can improve exercise tolerance and pulmonary function,alleviate anxiety and depression,and thereby enhance the quality of life in COPD patients.

The 2024 National Education Work Conference pointed out that at the current juncture of the critical period for achieving the goals and tasks of the 14th Five-Year Plan,the implementation of the Education Powerhouse Construction Plan Outline should be taken as the main line of work,and building first-class disciplines is an crucial task for a higher education powerhouse.In 2022,forensic medicine was officially listed as a first-level discipline under the medical category,presenting an un-precedented historical opportunity for the development of forensic medicine.The forensic medicine dis-cipline of Southern Medical University comprehensively improves the quality of talent cultivation and facilitates the construction of first-class disciplines as its main direction.It aims to initiate and imple-ment a high-level faculty team building plan featuring"combining recruitment and cultivation,inter-disciplinary integration";make vigorous efforts to establish a first-level doctoral program,refine advan-tageous second-level disciplines and research directions;and establish an innovative research platform from a high starting point with deep integration.The discipline adheres to moral cultivation and the Five Domains of Education simultaneous development,to build a high-quality talent joint training model.Guided by the construction of the national legal system and industry needs,the discipline will enhance social service capabilities.The forensic medicine construction in our university will continue to contribute to the rule of law in China and educational power.

Parathyromegaly refers to chronic enlargement of the parathyroid glands caused by multiple etiological factors. Pathological conditions, such as hyperparathyroidism, parathyroid hyperfunction, parathyroid adenoma, parathyroid cysts, and parathyroid carcinoma may all lead to parathyromegaly. Notably, calcium intake insufficiency and/or vitamin D insufficiency (CVI), which is the predominant etiology of parathyromegaly, now has been recognized as a global public health challenge. Chronic CVI induces negative calcium balance and relative low serum calcium level, stimulating compensatory parathyroid hyperplasia and enlargement. This progression triggers parathyroid hyperfunction and secondary hyperparathyroidism, resulting in bone mass loss, height reduction, kyphosis, osteoporosis, pathological fractures, metastatic vascular calcification and systemic abnormal calcium migration and calcinosis (such as urolithiasis). During the early stages of parathyromegaly, the condition remains preventable and treatable; However, delayed intervention may lead to irreversible tertiary hyperparathyroidism. CVI-associated parathyromegaly exhibits high prevalence and heterogeneous clinical manifestations, representing a critically underrecognized clinical entity. This article will systematically discuss the etiology, pathological characteristics, clinical consequences, and prevention and control strategies for CVI-related parathyromegaly.

Patients with initially diagnosed breast cancer and uncontrolled hyperthyroidism are at high risk of perioperative thyroid crisis. This article reports two cases of early-stage breast cancer initially diagnosed concurrently with uncontrolled primary hyperthyroidism. In Case 1, the patient received neoadjuvant chemotherapy to control breast cancer progression while concurrently taking antithyroid drugs to manage hyperthyroidism. Hyperthyroidism was controlled during chemotherapy, and the patient successfully underwent surgery after neoadjuvant chemotherapy. Case 2 involved recurrent primary hyperthyroidism with leukopenia after antithyroid drug therapy. Since leukopenia is a relative contraindication for antithyroid drugs, the patient underwent radioactive iodine therapy (iodine-131) and endocrine therapy for one month before proceeding with breast cancer surgery. Through a literature review, this article analyzes preoperative management strategies for uncontrolled hyperthyroidism in initially diagnosed breast cancer patients, emphasizing the importance of normalizing thyroid function to prevent thyroid crisis and reduce perioperative risks.

Gallbladder cancer is the most common malignant tumor of the biliary system,characterized by insidious growth,rapid progression,and skip metastasis.The 5-year overall survival rate is only 5%.Although targeted immunotherapies have emerged in recent years,they are still in the exploratory phase for the treatment of gallbladder cancer,and radical surgical resection remains the only potentially curative treatment.The main goal of surgery is to completely remove the tumor and perform systematic lymph node dissection to reduce the risk of recurrence.Thanks to advances in surgical techniques and continuous optimization of perioperative management,postoperative complications,and hospital mortality in patients undergoing extended radical surgery for gallbladder cancer have decreased.However,the complex mechanisms of gallbladder cancer spread and metastasis make it challenging to determine the optimal scope of surgical resection.Clinical guidelines from different countries and hepatobiliary surgery centers often vary on surgical options,especially regarding the reasonable extent of liver resection,the scope of lymph node dissection and its impact on prognosis,and whether routine extrahepatic bile duct resection should be performed.There remains significant controversy in these areas.Future extensive prospective cohort studies are still needed to provide more evidence-based medical data for the surgical treatment of gallbladder cancer.When designing a surgical plan,surgeons must consider preoperative examination results,intraoperative findings,and pathological evaluation of frozen sections.A balance must be struck between radical treatment and safety and effectiveness.The most appropriate surgical method for each patient should be chosen while also emphasizing establishing a multidisciplinary collaborative system.Based on accurate tumor staging,postoperative adjuvant therapies should be integrated to continue making progress in improving patient prognosis.

This consensus will introduce the characteristics of fillers used in the surgical cavities of domestic nasal surgery patients based on relevant literature and expert opinions. It will also provide recommendations for the selection of cavity fillers for different nasal diseases, with chronic sinusitis as a representative example.
Humans ; Nasal Cavity/surgery* ; Nasal Surgical Procedures ; China ; Consensus ; Sinusitis/surgery* ; Dermal Fillers

Tailored lipid nanoparticles (LNPs)-mediated small interfering RNA (siRNA) nanomedicines show promise in treating liver disease, such as acute liver injury (ALI) and non-alcoholic steatohepatitis (NASH). However, constructing LNPs that address biosafety concerns, ensure efficient delivery, and target specific hepatic subcellular fractions has been challenging. To evade above obstacles, we develop three novel self-degradable "gemini-like" ionizable lipids (SS-MA, SS-DC, SS-MH) by incorporating disulfide bonds and modifying the length of ester bond and tertiary amino head. Our findings reveal that the disulfide-bond-bridged LNPs exhibit reduction-responsive drug release, improving both biosafety and siRNA delivery efficiency. Furthermore, the distance of ester bond and tertiary amino head significantly influences the LNPs' pK _a, thereby affecting endosomal escape, hemolytic efficiency, absorption capacity of ApoE, uptake efficiency of hepatocytes and liver accumulation. We also develop the modified-mannose LNPs (M-LNP) to target liver macrophages specifically. The optimized M-MH_LNP@TNFα exhibits potential in preventing ALI by decreasing tumor necrosis factor α (TNFα) levels in the macrophages, while MH_LNP@DGAT2 could treat NASH by selectively degrading diacylglycerol O-acyltransferase 2 (DGAT2) in the hepatocytes. Our findings provide new insights into developing novel highly effective and low-toxic "gemini-like" ionizable lipids for constructing LNPs, potentially achieving more effective treatment for hepatic diseases.

Myelin is an essential structure that facilitates rapid saltatory conduction in the nervous system. Discrepancies in myelin microstructure are a hallmark of numerous neurological disorders, rendering the assessment of myelin integrity and content an indispensable tool in clinical diagnostics and neuroscience research. Extensive research has been dedicated to scrutinizing its biochemical makeup and morphology under normal, pathological, and experimental conditions over the years. In this review, we present an updated summary of the myelin sheath's structure, composition, and developmental trajectory. We systematically enumerate and contrast eight prevalent myelin staining techniques across dimensions of sensitivity, specificity, and resolution, delving into their underlying staining principles. With an initial application of myelin histology on the mouse demyelination model, our review accentuates the accurate delineation of myelination and the microstructural analysis of the myelin sheath. Such insights are anticipated to significantly contribute to the evaluation and understanding of white matter pathologies.
Myelin Sheath/metabolism* ; Animals ; Humans ; Demyelinating Diseases/pathology* ; Staining and Labeling/methods*

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