The xylitol dehydrogenase(XDH)is a crucial enzyme involved in the xylose utilization in pentose-catabolizing yeasts and fungi.In addition to producing xylulose,XDH can also be employed to develop a biosensor for monitoring xylitol concentration.In this study,the gene encoding the thermophilic fungus Talaromyces emersonii XDH(TeXDH)was heterologously expressed in Escherichia coli BL21(DE3)at 16 ℃ in the soluble form.Recombinant TeXDH with high purity was purified by using a Ni-NTA affinity column.Size-exclusion chromatography and SDS-PAGE analysis demonstrated that the puri-fied recombinant TeXDH exists as a native trimer with a molecular mass of approximately 116 kD,and is composed of three identical subunits,each with a molecular weight of around 39 kD.The TeXDH strictly preferred NAD+as a coenzyme to NADP+.The optimal temperature and pH of the TeXDH were 40 ℃and 10.0,respectively.After EDTA treatment,the enzyme activity of TeXDH decreased to 43.26％of the initial enzyme activity,while the divalent metal ions Mg2+or Ca2+could recover the enzyme activity of TeXDH,reaching 103.32％and 110.69％of the initial enzyme activity,respectively,making them the optimal divalent metal ion cofactors for TeXDH enzyme.However,the divalent metal ions of Mn2+,Ni2+,Cu2+,Zn2+,Co2+,and Cd2+significantly inhibited the activity of TeXDH.ICP-MS and molecular doc-king studies revealed that 1 mol/L of TeXDH bound 2 mol/L Zn2+ions and 1 mol/L Mg2+ion.Further-more,TeXDH exhibited a high specificity for xylitol,laying the foundation for the development of future xylitol biosensors.

The xylitol dehydrogenase(XDH)is a crucial enzyme involved in the xylose utilization in pentose-catabolizing yeasts and fungi.In addition to producing xylulose,XDH can also be employed to develop a biosensor for monitoring xylitol concentration.In this study,the gene encoding the thermophilic fungus Talaromyces emersonii XDH(TeXDH)was heterologously expressed in Escherichia coli BL21(DE3)at 16 ℃ in the soluble form.Recombinant TeXDH with high purity was purified by using a Ni-NTA affinity column.Size-exclusion chromatography and SDS-PAGE analysis demonstrated that the puri-fied recombinant TeXDH exists as a native trimer with a molecular mass of approximately 116 kD,and is composed of three identical subunits,each with a molecular weight of around 39 kD.The TeXDH strictly preferred NAD+as a coenzyme to NADP+.The optimal temperature and pH of the TeXDH were 40 ℃and 10.0,respectively.After EDTA treatment,the enzyme activity of TeXDH decreased to 43.26％of the initial enzyme activity,while the divalent metal ions Mg2+or Ca2+could recover the enzyme activity of TeXDH,reaching 103.32％and 110.69％of the initial enzyme activity,respectively,making them the optimal divalent metal ion cofactors for TeXDH enzyme.However,the divalent metal ions of Mn2+,Ni2+,Cu2+,Zn2+,Co2+,and Cd2+significantly inhibited the activity of TeXDH.ICP-MS and molecular doc-king studies revealed that 1 mol/L of TeXDH bound 2 mol/L Zn2+ions and 1 mol/L Mg2+ion.Further-more,TeXDH exhibited a high specificity for xylitol,laying the foundation for the development of future xylitol biosensors.

As artificial intelligence technology rapidly advances, its deployment within the medical sector presents substantial ethical challenges. Consequently, it becomes crucial to create a standardized, transparent, and secure framework for processing medical data. This includes setting the ethical boundaries for medical artificial intelligence and safeguarding both patient rights and data integrity. This consensus governs every facet of medical data handling through artificial intelligence, encompassing data gathering, processing, storage, transmission, utilization, and sharing. Its purpose is to ensure the management of medical data adheres to ethical standards and legal requirements, while safeguarding patient privacy and data security. Concurrently, the principles of compliance with the law, patient privacy respect, patient interest protection, and safety and reliability are underscored. Key issues such as informed consent, data usage, intellectual property protection, conflict of interest, and benefit sharing are examined in depth. The enactment of this expert consensus is intended to foster the profound integration and sustainable advancement of artificial intelligence within the medical domain, while simultaneously ensuring that artificial intelligence adheres strictly to the relevant ethical norms and legal frameworks during the processing of medical data.
Artificial Intelligence/legislation & jurisprudence* ; Humans ; Consensus ; Computer Security/standards* ; Confidentiality/ethics* ; Informed Consent/ethics*

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal hematopoietic stem cell disease caused by abnormal expression of glycosylphosphatidylinositol (GPI) on the cell membrane due to mutations in the phosphatidylinositol glycan class A(PIGA) gene. It is commonly characterized by intravascular hemolysis, repeated thrombosis, and bone marrow failure, as well as multiple systemic involvement symptoms such as renal dysfunction, pulmonary hypertension, swallowing difficulties, chest pain, abdominal pain, and erectile dysfunction. Due to the rarity of PNH and its strong heterogeneity in clinical manifestations, multidisciplinary collaboration is often required for diagnosis and treatment. Peking Union Medical College Hospital, relying on the rare disease diagnosis and treatment platform, has invited multidisciplinary clinical experts to form a unified opinion on the diagnosis and treatment of PNH, and formulated the Expert Consensus of Multidisciplinary Diagnosis and Treatment for Paroxysmal Nocturnal Hemoglobinuria (2024), with the hope of promoting the standardization of PNH diagnosis and treatment.

ObjectiveGastric cancer (GC) seriously affects human health and life, and research has shown that it is closely related to the serine/glycine metabolism. The proliferation ability of tumor cells is greatly influenced by the metabolism of serine and glycine. The aim of this study was to investigate the molecular mechanism of serine/glycine metabolism can affect the proliferation of gastric cancer cells. MethodsIn this work, a stable metabolic dynamic model of gastric cancer cells was established via a large-scale metabolic network dynamic modeling method in terms of a potential landscape description of stochastic and non-gradient systems. Based on the regulation of the model, a quantitative analysis was conducted to investigate the dynamic mechanism of serine/glycine metabolism affecting the proliferation of gastric cancer cells. We introduced random noise to the kinetic equations of the general metabolic network, and applied stochastic kinetic decomposition to obtain the Lyapunov function of the metabolic network parameter space. A stable metabolic network was achieved by further reducing the change in the Lyapunov function tied to the stochastic fluctuations. ResultsDespite the unavailability of a large number of dynamic parameters, we were able to successfully construct a dynamic model for the metabolic network in gastric cancer cells. When extracellular serine is available, the model preferentially consumes serine. In addition, when the conversion rate of glycine to serine increases, the model significantly upregulates the steady-state fluxes of S-adenosylmethionine (SAM) and S-adenosyl homocysteine (SAH). ConclusionIn this paper, we provide evidence supporting the preferential uptake of serine by gastric cancer cells and the important role of serine/glycine conversion rate in SAM generation, which may affect the proliferation ability of gastric cancer cells by regulating the cellular methylation process. This provides a new idea and direction for targeted cancer therapy based on serine/glycine metabolism.

Epidemiology and medical statistics are essential courses for undergraduate students majoring in clinical medicine. By studying the two courses, they can obtain the core skills for their future clinical practice. High-level medical schools both at home and abroad have accumulated successful experiences in curriculum, teaching methods and teaching models of the two disciplines. These colleges have also carried out the exploration of the curriculum reform centering on "organ systems integration". This paper summarizes the current status of epidemiology and medical statistics teaching and curriculum integration in representative medical schools both at home and abroad, and puts forward suggestions for deepening teaching reform and optimizing the curriculum system to provide reference for the integration of epidemiology and medical statistics curriculums for undergraduate students majoring in clinical medicine in China.

Objective To investigate the effects of different concentrations of adapalene on the morphology and functions of neuroblastoma cell line SH-SY5Y,as well as its role in inducing cell differentiation and apoptosis.Methods SH-SY5Y cells were divided into control group,low concentration(0.1 pM and 1 pM)adapalene groups,and high concentration(10 μM)adapalene group.Time-lapse microscopy was used to observe the morphological changes of SH-SY5Y cells.Immunofluorescence staining was performed to detect the expression of neuronal specific marker βⅢ-tubulin and mature neuronal marker neurofilament heavy polypeptide(NFH).Multi-electrode array was used to record the electrophysiological features of SH-SY5Y cells.Cell apoptosis was evaluated using a cell apoptosis detection kit.Results Low concentrations of adapalene promoted the formation of neurite outgrowth in SH-SY5Y cells,with the neurites interconnected to form a network.Spontaneous discharge activity was observed in SH-SY5Y cells treated with low concentrations of adapalene.Compared to the control group,the expression of βⅢ-tubulin and NFH increased in the 1 μM adapalene group,while the level of cell apoptosis increased in the high concentration adapalene group(P＜0.05).Conclusions Low concentrations of adapalene can induce differentiation of SH-SY5Y cells into mature functional neurons,while high concentrations of adapalene can induce apoptosis in SH-SY5Y cells.[Chinese Journal of Contemporary Pediatrics,2024,26(3):282-288]

The lingnan liver-soothing and spirit-regulating acupuncture and moxibustion technique,developed by Professor FU Wen-Bin,a renowned traditional Chinese medicine expert in Guangdong Province,represents an innovative achievement in acupuncture therapy for depression-related disorders.Drawing upon the rich legacy of master scholars,meticulous study of medical literature,and over three decades of continuous research and innovation,Professor FU has formulated this technique with profound influence and widespread application.By tracing the developmental trajectory of the Lingnan liver-soothing and spirit-regulating technique,this paper sheds light on its significant guiding principles and reference value for the development of other distinctive acupuncture techniques.Furthermore,it offers insights and inspiration for advancement in various fields of traditional Chinese medicine.

OBJECTIVE: To investigate the clinical effect of double pulley combined with suture bridge in the treatment of comminuted fracture of the lower pole of the patella. METHODS: From January 2018 to June 2020, 15 patients with comminuted fracture of the lower pole of the patella were treated with double pulley and suture bridge technology, including 9 males and 6 females, aged 28 to 68 years old with an average of (42.4±9.6) years old. All patients had obvious knee joint pain and limited movement after injury. All knee joints were examined by X-ray and CT, which confirmed that they were all comminuted fractures at the lower level of the patella. After operation, X-ray films of the knee joint were taken regularly to understand the fracture healing, the Insall Salvati index was measure, the range of motion of the joint was recorded, and the function of the knee joint was evaluateed by the Bostman scoring system. RESULTS: All the 15 patients were followed up for 7 to 24 months with an average of (11.4±4.2) months, and there was no obvious anterior knee pain. At the last follow-up, the knee joint range of motion of the affected limb was 105° to 140° with an average of (128.5±12.8) °, and the Insall Salvati index was 0.79 to 1.12 with an average of (0.92±0.18). The X-ray film showed that the patella was bone healing, and no anchor fell off, broken, or displaced fracture block was found. Bostman patellar fracture function score was 27.85±2.06, 13 cases were excellent, 2 cases were good. CONCLUSION Double pulley technique combined with suture bridge technique is reliable for reduction and fixation of comminuted fracture of the lower pole of patella, and patients can start functional exercise early after operation.
Male ; Female ; Humans ; Adult ; Middle Aged ; Aged ; Fractures, Comminuted/surgery* ; Fracture Fixation, Internal/methods* ; Patella/injuries* ; Bone Wires ; Fractures, Bone/surgery* ; Sutures ; Treatment Outcome

Objective: To identify the main metals involved in cognitive impairment in the Chinese oldest old, and explore the association between these metal exposures and cognitive impairment. Methods: A cross-sectional study was conducted on 1 568 participants aged 80 years and older from Healthy Aging and Biomarkers Cohort Study (2017 to 2018). Fasting venous blood was collected to measure the levels of nine metals (selenium, lead, cadmium, arsenic, antimony, chromium, manganese, mercury, and nickel). The cognitive function of these participants was evaluated by using the Chinese version of the Mini-Mental State Examination (CMMSE). The random forest (RF) was applied to independently identify the main metals that affected cognitive impairment. The multivariate logistic regression model and restricted cubic splines (RCS) model were used to further verify the association of the main metals with cognitive impairment. Results: The age of 1 568 study subjects was (91.8±7.6) years old, including 912 females (58.2%) and 465 individuals (29.7%) with cognitive function impairment. Based on the RF model (the out-of-bag error rate was 22.9%), the importance ranking of variables was conducted and the feature screening of five times ten-fold cross-validation was carried out. It was found that selenium was the metal that affected cognitive function impairment, and the other eight metals were not included in the model. After adjusting for covariates, the multivariate logistic regression model showed that with every increase of 10 μg/L of blood selenium levels, the risk of cognitive impairment decreased (OR=0.921, 95%CI: 0.889-0.954). Compared with the lowest quartile(Q₁) of blood selenium, the ORs (95%CI) of Q₃ and Q₄ blood selenium were 0.452 (0.304-0.669) and 0.419 (0.281-0.622) respectively. The RCS showed a linear dose-response relationship between blood selenium and cognitive impairment (P_nonlinear>0.05). Conclusion: Blood selenium is negatively associated with cognitive impairment in the Chinese oldest old.
Aged, 80 and over ; Female ; Humans ; Selenium ; Cohort Studies ; Cross-Sectional Studies ; Metals/analysis* ; Cognitive Dysfunction/epidemiology* ; China/epidemiology*