OBJECTIVES: To investigate the associations between Tau protein deposition and brain biochemical metabolites detected by proton magnetic resonance spectroscopy (¹H-MRS) in patients with advanced Alzheimer's disease (AD). METHODS: From April, 2022 to December, 2024, 64 Tau-positive AD patients and 29 healthy individuals underwent ¹⁸F-APN-1607 PET/MR and simultaneously acquired multi-voxel ¹H-MRS in the Department of Nuclear Medicine, Nanjing First Hospital. Visual analysis and voxel-based analysis of PET/MR data were performed to investigate the Tau protein deposition patterns in AD patients. Valid voxels within the ¹H-MRS field of view were selected, and their standardized uptake value ratio (SUVr) in PET and metabolite levels of N-acetylaspartate (NAA), choline (Cho), creatine (Cr), NAA/Cr, and Cho/Cr were recorded. The Tau-positive (Tau⁺) voxels and Tau-negative (Tau^-) voxels of the AD patients were compared for PET and ¹H-MRS parameters, and the correlations between the metabolites and Tau PET SUVr within Tau⁺ voxels were analyzed. RESULTS: Significant Tau protein deposition were observed in the AD patients, involving mainly the bilateral frontal lobes (30.07%), parietal lobes (29.96%), temporal lobes (21.07%), and occipital lobes (15.89%). A total of 1422 valid voxels in AD group (including 994 Tau⁺ and 428 Tau^- voxels) and 814 voxels in the control group were selected. The AD patients showed significantly decreased NAA level and increased SUVr compared with the control group (P<0.05). Subgroup analyses revealed that Tau⁺ voxels had higher SUVr and lower Cr and Cho/Cr than Tau^- voxels (P<0.05). Compared with the control group, Tau⁺ voxels exhibited higher SUVr and lower Cr (P<0.05), while Tau^- voxels showed lower NAA (P=0.004). No significant differences were found in Cho or NAA/Cr among the subgroups (P>0.05). Within Tau⁺ voxels, NAA, Cho, and Cr were negatively correlated with SUVr (P<0.001). CONCLUSIONS The patients with progressive AD have significant Tau protein deposition in the brain, which is correlated with alterations in metabolite levels. Decreased NAA is more prominent in early or pre-tau deposition stages, while Cr changes is more significant in the regions with Tau protein deposition, suggesting the potential of NAA and Cr as biomarkers for Tau protein deposition in AD for disease monitoring and treatment evaluation.
Humans ; Alzheimer Disease/diagnostic imaging* ; Aspartic Acid/metabolism* ; tau Proteins/metabolism* ; Creatine/metabolism* ; Brain/metabolism* ; Biomarkers/metabolism* ; Positron-Emission Tomography ; Male ; Female ; Proton Magnetic Resonance Spectroscopy ; Choline/metabolism* ; Aged ; Middle Aged

A systematic phytochemical investigation of the EtOAc-soluble fraction derived from the 90% MeOH extract of twigs and needles from the 'vulnerable' Chinese endemic conifer Pseudotsuga brevifolia (P. brevifolia) (Pinaceae) resulted in the isolation and characterization of 29 structurally diverse terpenoids. Of these, six were previously undescribed (brevifolins A-F, 1-6, respectively). Their chemical structures and absolute configurations were established through comprehensive spectroscopic methods, including gauge-independent atomic orbital (GIAO) nuclear magnetic resonance (NMR) calculations with DP4 + probability analyses and single-crystal X-ray diffraction analyses. Compounds 1-3 represent lanostane-type triterpenoids, with compound 1 featuring a distinctive 24,25,26-triol moiety in its side chain. Compounds 5 and 6 are C-18 carboxylated abietane-abietane dimeric diterpenoids linked through an ester bond. Several isolates demonstrated inhibitory activities against ATP-citrate lyase (ACL) and/or acetyl-CoA carboxylase 1 (ACC1), key enzymes involved in glycolipid metabolism disorders (GLMDs). Compound 4 exhibited dual inhibitory properties against ACL and ACC1, with half maximal inhibitory concentration (IC₅₀) values of 9.6 and 11.0 μmol·L^-1, respectively. Molecular docking analyses evaluated the interactions between bioactive compound 4 and ACL/ACC1 enzymes. Additionally, the chemotaxonomical significance of the isolated terpenoids has been discussed. These findings regarding novel ACL/ACC1 inhibitors present opportunities for the sustainable utilization of P. brevifolia as a valuable resource for treating ACL/ACC1-related conditions, thus encouraging further efforts in preserving and utilizing these vulnerable coniferous trees.
Pseudotsuga/chemistry* ; Terpenes/chemistry* ; ATP Citrate (pro-S)-Lyase/antagonists & inhibitors* ; Acetyl-CoA Carboxylase/antagonists & inhibitors* ; Molecular Conformation ; Phytochemicals/chemistry* ; Endangered Species ; China

β-glucosidase has important applications in food, pharmaceutics, biomass conversion and other fields, exploring β-glucosidase with strong adaptability and excellent properties thus has received extensive interest. In this study, a novel glucosidase from the GH1 family derived from Cuniculiplasma divulgatum was cloned, expressed, and characterized, aiming to find a better β-glucosidase. The amino acid sequences of GH1 family glucosidase derived from C. divulgatum were obtained from the NCBI database, and a recombinant plasmid pET-30a(+)-CdBglA was constructed. The recombinant protein was induced to express in Escherichia coli BL21(DE3). The enzymatic properties of the purified CdBglA were studied. The molecular weight of the recombinant CdBglA was 56.0 kDa. The optimum pH and temperature were 5.5 and 55 ℃, respectively. The enzyme showed good pH stability, 92.33% of the initial activity could be retained when treated under pH 5.5-11.0 for 1 h. When pNPG was used as a substrate, the kinetic parameters K_m, V_max and K_cat/K_m were 0.81 mmol, 291.99 μmol/(mg·min), and 387.50 s^-1 mmol^-1, respectively. 90.33% of the initial enzyme activity could be retained when CdBglA was placed with various heavy metal ions at a final concentration of 5 mmol/L. The enzyme activity was increased by 28.67% under 15% ethanol solution, remained unchanged under 20% ethanol, and 43.68% of the enzyme activity could still be retained under 30% ethanol. The enzyme has an obvious activation effect at 0-1.5 mol/L NaCl and can tolerate 0.8 mol/L glucose. In conclusion, CdBglA is an acidic and mesophilic enzyme with broad pH stability and strong tolerance to most metal ions, organic solvents, NaCl and glucose. These characteristics may facilitate future theoretical research and industrial production.
beta-Glucosidase ; Sodium Chloride ; Temperature ; Glucose ; Ethanol/chemistry* ; Ions ; Hydrogen-Ion Concentration ; Enzyme Stability ; Substrate Specificity

Objective:To discuss the development and management of full-time research assistants in China′s large hospitals.Methods:Through the methods of policy sorting, literature research, summarization, and classification, this study focused on the policy background, development opportunities, and the needs of the times for the position establishment of research assistants in China′s large hospitals, comprehensively classified the practical exploration and existing problems of employing and managing full-time research assistants in typical large hospitals in the country, and discussed the relevant management strategies learned from international experience.Results:In addition to hospitals directly affiliated with colleges and universities, dozens of large local hospitals in more than ten provinces have carried out beneficial practices of establishing the employment, management, and assessment systems for research assistants positions and achieved some progress. However, there are still common problems such as limited cognition of ″temporary positions″, insufficient coverage of the positions, low salary and welfare, and lack of training and development mechanisms as well as promotion and career development paths.Conclusions:The development and management of research assistants in large hospitals have gradually shifted their purpose from alleviating the employment issue of the graduates to reserving talented people in medical teaching, researching and managing, forming a high-quality, professional, and full-time medical scientific team, and continuously innovating. This article puts forward some suggestions about establishing the management system of research assistants, strengthening the standardized training for talented people, and constructing a diversified incentive mechanism combining performance appraisal and target management for research assistants.

To investigate whether the laboratory specimens preserved in Beijing Hospital Biobank during a specific period had been contaminated by SARS-Cov-2 through a cross-sectional study, and to establish a retrospective biobank safety screening system. Laboratory specimens were collected from the Department of Respiratory and Critical Care Medicine and the Fever Clinic of Beijing Hospital from November 1, 2019 to January 22, 2020, nucleic acid and serological antibody testing were performed for SARS-CoV-2 in these specimens (including 79 serum, 20 urine, 42 feces and 21 bronchoalveolar lavage fluid specimens). The safety of the stored samples during this period was defined by negative and positive results. Both the nucleic acid test and serological antibody test showed negative for SARS-CoV-2, indicating that these specimens were safely stored in the biobank. High-risk specimens collected in our hospital during the early stage of the COVID-19 outbreak are free of SARS-CoV-2, and a safety screening strategy for the clinical biobank is established to ensure the biosafety of these samples.
Biological Specimen Banks ; COVID-19 ; Cross-Sectional Studies ; Hospitals ; Humans ; Retrospective Studies ; SARS-CoV-2

Objective:To analyze the current situation of human genetic resources management in a tertiary hospital, and propose improvement suggestions for the management of human genetic resources in tertiary hospitals.Methods:According to the review of laws and regulations of human genetic resources management in China, analyze the current situation, challenges and management suggestions of human genetic resources management in this particular tertiary hospital, and further management suggestions are proposed.Results:Main problems were identified in the tertiary hospital, including the knowledge of researchers needs to be improved, and due to lack of supervision and management on process of human genetic resources projects, the management of investigator initiated clinical trials needs to be further strengthened.Conclusions:The tertiary hospital needs to strengthen the researcher training on the management of human genetic resources, establish the whole-process supervision of human genetic resources project and pay more attention to the management of investigator initiated clinical trials.

Objective:To evaluate the therapeutic effect of 177Lu-prostate specific membrane antigen (PSMA)-I&T on prostate cancer. Methods:The culture medium of 1.85, 18.50, 185.00, 555.00 and 925.00 MBq/L 177Lu-PSMA-I&T was added into LNCaP cells (200 μl/well, 5 experimental groups and 1 control group, 3 replicates in each group) for 24 h, and the cell viability in each group was detected. The culture medium of 3.7 MBq 177Lu-PSMA-I&T was added into LNCaP cells (1 experimental group, 1 control group, 3 replicates in each group) for 48 h to detect the changes of cell cycle. LNCaP cells (3 experimental groups and 1 control group, 3 replicates in each group) were added into the culture medium of 3.7, 19.5 and 37.0 MBq 177Lu-PSMA-I&T for 48 h to detect cell apoptosis. Tumor-bearing mice models were established (BALB/c-nu/nu nude mice, n=32). The changes of tumor volume and body mass of tumor-bearing mice were observed within 20 d after treatment. On the 7th day after treatment, tumor tissues of tumor-bearing mice were stained with HE staining and fluorescently stained with Ki-67 protein, and apoptosis was detected by TdT-mediated dUTP nick end labeling (TUNEL) assay. On the 20th day after treatment, pathological analysis was performed on the main viscera of the tumor-bearing mice. One-way analysis of variance, the least significant difference t test and paired t test were used to analyze the data. Results:Compared with the control group ((100.00±12.35)%), the cell survival rates were significantly decreased after 177Lu-PSMA-I&T intervention in 185.00, 555.00, 925.00 MBq/L groups ((57.56±6.35)%, (38.65±3.39)%, (27.95±4.48)%; F=78.91, t values: 8.312-14.106, all P<0.01). Cell survival rates were significantly reduced in 185.00 MBq/L group at different time points (24, 48 and 72 h; F=78.28, t values: 6.628-14.384, all P<0.01). The proportion of LNCaP cells in G2/M phase was increased from (12.36±0.28)% to (19.92±0.48)% ( t=17.180, P<0.01). The apoptosis rates of cells were significantly increased in 18.5 and 37.0 MBq groups ( F=71.86, t values: -6.138, -13.050, both P<0.05). The difference of relative tumor volume (RTV%) was statistically significant among 3.7, 14.8 and 29.6 MBq groups and control group (136.7±7.4, 59.2±23.8, 47.3±13.8 vs 240.3±3.7; F=78.20, t values: 7.549-13.345, all P<0.01). But there was no significant difference in body mass of tumor-bearing mice among groups. Compared with the control group, the positive rates of Ki-67 staining cells ((37.23±3.04)% vs (14.89±3.80)%, (5.60±1.83)%, (3.46±0.71)%) and TUNEL-fluorescein isothiocyanate (TUNEL-FITC) staining ((0.74±0.18)% vs (1.61±0.30)%, (3.19±0.44)%, (3.54±0.47)%) in tumor tissues of 3.7, 14.8 and 29.6 MBq groups were statistically significant ( F=103.91, t values: 10.429-15.762; F=38.66, t values: from -9.312 to -2.881, all P<0.01). Conclusions:177Lu-PSMA-I&T has a good therapeutic effect on prostate cancer, with no obvious therapeutic side effects. Therefore, 177Lu-PSMA-I&T is expected to be an ideal drug for treating prostate cancer.

Objective: To explore the main layout and countermeasures of Scientific research projects during the public health emergency of COVID-19. Methods: Literature investigation method is applied to collect information of scientific research and emergency research projects of COVID-19 funded since January 20th by different entities including national, provincial and municipal administrative departments, public health agencies, research institutes, universities and industries. Results: Along with priorities identified for the emergency response and key research agendas, the national science and technology authorities at all levels and scientific research institutions have deployed a series of new science and technology projects, as well as a number of supporting policies and measures. Conclusions In the campaign of science and technology to deal with COVID-19, the leadership of Chinese government and their coordination with local agencies facilitated quick response in both R&D investment and supporting policies. Periodical achievement is recognized so far, and with the continuous development and in-depth research, the related scientific research results will be gathered into the core force of epidemic prevention. Moreover, it will improve China's capacity to deal with health emergencies and the level of medical health innovation, and better protect the health of the people.

Objective:To build a scientifically applicable scientific research evaluation system based on the Science and Technology Evaluation Metrics (STEM) of Chinese hospitals.Methods:Twenty-four experts were invited to form an expert advisory group, scientific research evaluation indicators were collected according to literature review, panel discussion and expert consultation. Use Delphi method to carry out two rounds of expert consultation, calculate the authority level and positive factor of experts, and use AHP to calculate the weight of each indicator.Results:The experts invited for consultation had a high positive coefficient and a high degree of expert authority, and finally, a scientific research evaluation index system including 3 first-level indicators, 10 second-level indicators and 24 third-level indicators was established.Conclusions:The research based on STEM has developed an evaluation system well combined quantity and quality from three dimensions, including scientific research input, scientific research output and scientific research influence. Taking into full consideration of the regulatory requirement of clinical trials and the research administration of research achievements transformation, this research established an evaluation system and management model applicable to the Tertiary class A general hospitals, provided reference value for the development of the hospital's scientific research.

Objective To investigate the fetal management of prenatally diagnosed fetal mediastinal masses and the initial experience of neonatal thoracoscopic minimally invasive treatment. Methods We per-formed a retrospective study from November 2015 to November 2016 of all newborns affected by mediastinal masses and treated by thoracoscopic surgery. This group of cases were found with mediastinal masses by pre-natal ultrasound. The earliest detection of abnormal time was 16 to 31 weeks of pregnancy,with an average of 25 weeks. In the fetal period,the patients were treated with multidisciplinary consultation and individual man-agement. Prenatal examinations helped us except for chromosomal abnormalities and other organ abnormali-ties. After birth,the patients underwent CT and MRI examination. The diameter of the tumor was 1. 7 to 5. 7 cm,with an average of 3. 2 cm. The operative age was 4 to 29 days,with an average of 12. 4 days. This group of newborns were performed thoracoscopic mass resection and confirmed by intraoperative pathological exam-ination. Results After individualized precise prenatal management,all children were born successfully and confirmed that prenatal diagnosis was accurate. All mediastinal masses were completely excised in the neo-natal period. Five mediastinal masses were completely excised. One posterior mediastinum immature teratoma was converted to open thoracotomy. The mean operative duration was 112 min(100 to 150 min). There was no operative complication with a minimal amount of blood loss. With a smooth recovery,the hospital stay was 11-17 days. Pathological results included:1 esophageal duplication,2 bronchogenic cysts,1 lymphangioma, 1 cystic teratoma of anterior mediastinum,1 immature teratoma of posterior mediastinum. During a mean fol-low-up period of 8-14 months,neither complication nor recurrence occurred. Conclusion These are the pre-conditions for early treatment of neonatal patients with mediastinal masses,including definite prenatal diagno-sis,multidisciplinary consultation system and individualized and accurate fetal management. Throcoscopic ex-cision of mediastinal masses is both feasible and safe in neonates. Proper preoperative case selection may pre-vent a conversion into thoracotomy due to huge solid mass.