ObjectiveTo establish background data for a 90-day feeding trial of SD rats to ensure the reliability of research data. MethodsBackground data from six independent 90-day feeding trials of SD rats conducted by the National Center for Safety Evaluation of Drugs from 2020 to 2023 were summarized. These studies involved a blank control group of 120 SPF-grade 4-week-old SD rats, with an equal number of males and females, which were only given standard full-nutrient pelleted rat feed. After the quarantine period, the animals were observed for an additional 90 days, followed by intraperitoneal injection of Zoletil (50 mg/mL) for anesthesia, blood sampling, euthanasia, and necropsy. By analyzing the data from the blank control group, a relevant background database for SD rats was established. ResultsBoth male and female rats exhibited steady weight gain, with a more pronounced increase in male rats. Within 90 days, the average body weight of male and female rats increased to over 500 g and 300 g, respectively. Three weeks later, the average daily food intake of male rats stabilized at approximately 25~28 g per rat, while that of female rats remained stable at approximately 16~19 g per rat. The food utilization rate of all animals gradually decreased from the first week of the experiment. In the white blood cell (WBC) differential count results, significant differences were observed in the counts of WBCs, neutrophils (Neut), lymphocytes (Lymph), and monocytes (Mono) between males and females (P<0.001). However, there were no significant differences in the percentages of neutrophil (%Neut), lymphocyte (%Lymph), and monocyte (%Mono) between the sexes (P>0.05). The average red blood cell count (RBC), hemoglobin concentration (HGB), hematocrit (HCT), platelet count (PLT), prothrombin time (PT), and activated partial thromboplastin time (APTT) were higher in male animals than in female animals (P<0.05). The average values of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), creatine phosphokinase (CK), lactate dehydrogenase (LDH), glucose (GLU), and triglyceride (TG) in male rats were higher than those in female rats (P<0.05). The urinary pH range for male animals was 5.0 to 8.5, while for female animals it was 6.5 to 9.0. The majority of male animals had a urinary specific gravity lower than 1.020, and the majority of female animals had a urinary specific gravity lower than 1.015. The weights of various organs (excluding the adrenal glands and reproductive organs) in male animals were heavier than those in female animals (P<0.001), while the organ/body weight ratios (excluding the kidneys and reproductive organs) of female animals were higher than those of male animals (P<0.001). ConclusionThis study summarizes the background reference ranges for body weight, food intake, hematology, and serum biochemistry indicators in SPF-grade SD rats in the untreated control group from six 90-day feeding trials conducted by the National Center for Safety Evaluation of Drugs. It provides important reference data for related research. By summarizing the background and spontaneous histopathological changes in rats, this study aids in the standardization and normalization of subsequent research, as well as in the evaluation and analysis of abnormal results.

ObjectiveTo establish a qualitative and quantitative analysis method for chemical constituents in Liu Junzitang（LJZT）， and to clarify its material basis. MethodThe chemical constituents in LJZT were analyzed by ultra performance liquid chromatography-quadrupole-time-of-flight mass spectrometry（UPLC-Q-TOF-MS/MS）， and the resulting compounds were identified by using databases， such as MassBank， PubChem， ChemSpider， Traditional Chinese Medicine Systems Pharmacology Database and Analytical Platform（TCMSP）， and by combining with relevant literature. UPLC was used to establish a quantitative method for analysis of 9 compounds in LJZT， including liquiritin， hesperidin， lobetyolin， liquiritigenin， glycyrrhizic acid， nobiletin， tangeretin， atractylenolide Ⅱ and Ⅰ. ResultBy combining the relevant literature， database and MS information， a total of 79 compounds were identified from LJZT， including 31 flavonoids， 15 terpenoids， 14 nitrogen-containing compounds， 6 phenylpropanoids， 6 organic acids and 7 other compounds. The established quantitative analytical method for the nine representative components showed good linearity within their respective linear ranges， and the precision， stability， reproducibility and recovery were in accordance with the requirements. The quantitative results showed that the contents of liquiritin， hesperidin， lobetyolin， liquiritigenin， glycyrrhizic acid， nobiletin， tangeretin， atractylenolide Ⅱ and Ⅰ in LJZT were 0.376 5， 2.602 1， 0.082 6， 0.128 1， 1.778 6， 0.015 7， 0.006 7， 0.030 4， 0.003 2 mg·g^-1， respectively. ConclusionThe established method can quickly， sensitively and accurately analyze the chemical constituents in LJZT， clarify that the material basis of LJZT is mainly flavonoids， terpenoids and nitrogen-containing compounds， and simultaneously determine the contents of the 9 components， which can lay a foundation for the research on quality control， mechanism and clinical application of LJZT.

Objective To observe the effect of a new cell delivery tool(MSC exo)on the proliferation of pancreatic cancer by transferring targeted genes.Methods Transmission Electron Microscope(TEM)and Nanoparticle Tracking Analysis(NTA)were used to identify human mesenchymal stem cell exosomes(MSC-exo)and transport miR-450a-5p into CFPAC-1,to explore the effect of miR-450a-5p targeting BZW2 on inhibiting the proliferation of pancreatic cancer cells.Results The expression of miR-450a-5p was low in pancreatic cancer tissue(P<0.05),and the expression of CD63 and TSG101 of MSC-exo-miR-450a-5p in CFPAC-1 cells was higher than that of MSC-exo by Western blot(P<0.05).CCK-8 and EdU results showed that MSC-exo-miR-450a-5p significantly inhibited the proliferation of CFPAC-1 cells(P<0.05).Cell scratch and Transwell experiments showed that MSC-exo-miR-450a-5p can inhibit the migration and invasion of CFPAC-1 cells(P<0.05).Through dual luciferase assay,it was confirmed that miR-450a-5p targets BZW2,and RT-qPCR and Western blotting showed a negative correlation(P<0.05)between miR-450a-5p and BZW2 expression.Overexpression of BZW2,CCK-8,EdU,cell scratch,and Transwell experiments confirmed that pc-BZW2 reversed the anti-cancer function of MSC-exo-miR-450a-5p on CFPAC-1.Western blot detected PCNA,Ki-67,MMP2,MMP9,and the results were consistent with the above experiments(P<0.05).Conclusion hMSC exo is a new delivery system,targeting BZW2 to transport miR-450a-5p to inhibit the biological malignancy of pancreatic cancer cells,which provides an important clue for the research of targeted treatment of pancreatic cancer.

Objective:To evaluate the relationship between hippocampal receptor-interacting protein kinase-1 (RIPK1) and nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3) inflammasomes in postoperative neurocognitive dysfunction of aged rats with chronic knee arthritis pain.Methods:Sixty-four healthy male Sprague-Dawley rats, aged 18 months, weighing 500-550 g, were divided into 4 groups ( n=16 each) using a random number table method: chronic knee arthritis pain group (group P), chronic knee arthritis pain+ operation group (group PS), RIPK1 inhibitor necrostatin-1+ chronic knee arthritis pain+ operation group (group NPS), and DMSO+ chronic knee arthritis pain+ operation group (group DPS). The knee arthritis model was prepared by intra-articular injection of monosodium iodoacetate (MIA) 1 mg into the left knee joint, and 12 weeks later exploratory laparotomy was performed under sevoflurane anesthesia. Necrostatin-1 6.25 mg/kg and the equal volume of DMSO were intraperitoneally injected at 1 h before operation in NPS group and DPS group, respectively. Thermal pain threshold was measured at 1 week before MIA injection and 6 and 12 weeks after MIA injection. Morris water maze test was used to evaluate the cognitive function at 7 days after surgery. Hippocampal tissues were obtained for microscopic examination of the pathological changes (after HE staining) and for determination of the expression of RIPK1, phosphorylated RIPK1 (p-RIPK1), NLRP3, activated cysteine-aspartic protease caspase-1 (cl-caspase-1), apoptosis-associated speck-like protein containing a CARD (ASC) (by Western blot) and contents of interleukin-1beta (IL-1β) and IL-18 (by enzyme-linked immunosorbent assay). Results:Thermal pain threshold was significantly decreased at 6 and 12 weeks after MIA injection as compared with that before injection ( P<0.05), and there was no significant difference in thermal pain threshold among the four groups ( P>0.05). Compared with P group, the escape latency was significantly prolonged, the time of staying at the original platform quadrant was shortened, the number of crossing the original platform was reduced, the expression of RIPK1, p-RIPK1, NLRP3, cl-caspase-1 and ASC was up-regulated, and the contents of IL-1β and IL-18 were increased ( P<0.05), and pathological changes of hippocampal neurons were marked in PS group, DPS group and NPS group. Compared with PS group and DPS group, the escape latency was significantly shortened, the time of staying at the original platform quadrant was prolonged, the number of crossing the original platform was increased, the expression of RIPK1, p-RIPK1, NLRP3, cl-caspase-1 and ASC was down-regulated, the contents of IL-1β and IL-18 were decreased ( P<0.05), and pathological changes of hippocampal neurons were significantly attenuated in NPS group. Conclusions:Postoperative hippocampal RIPK1 function is enhanced in aged rats with chronic knee arthritis pain, which then activates NLRP3 inflammasomes, triggering neuroinflammation, and this process may be involved in the mechanism of postoperative neurocognitive dysfunction.

Compared with the global average, the incidence rate of nasopharyngeal carcinoma (NPC) in China is higher, particularly in the southern regions where the mortality rate has remained persistently high. Nimotuzumab, a targeted therapy that acts on the epidermal growth factor receptor, has prompted continuous progress in NPC treatment. The combination of nimotuzumab with traditional radiotherapy and chemotherapy can enhance treatment efficacy, reduce adverse reactions, and improve patients’ quality of life. This article summarizes current research findings from this perspective to provide diagnostic and therapeutic strategies for NPC treatment.

The 18th National Postgraduate Symposium on Environmental and Occupational Medicine, co-sponsored by the Editorial Board of Journal of Environmental and Occupational Medicine and the School of Public Health of Sun Yat-sen University, was successfully held on August 22 to 25, 2024 in Guangzhou, Guangdong Province, China. Adhering to the theme of “Research and practice: Healing the schism”, the symposium aims to enliven academic thinking, expand research horizons, encourage innovation, enhance inter-university exchanges, and strengthen talent cultivation, especially to promote the close integration of academic research and public health practice. A total of 105 papers were received from 38 universities. The symposium also gathered about 160 participants, mainly authors postgraduates from universities and experts and professors in the field of environmental and occupational medicine. All the participants discussed the latest research advances and future development trends of environmental and occupational medicine, and endeavor to apply the research results in public health practice.

On May 25, 2024, Shanghai Municipal Administration for Market Regulation released Shanghai local standard Requirements for Outdoor Smoking Areas Setting Up and Management (DB 31/T 1482‒2024) (hereinafter referred to as Standard), which scheduled for official implementation from September 1, 2024. This article provided an interpretation of the key provisions in the Standard, with a particular emphasis on the scope of application, establishment and management requirements. In addition, the significance and potential difficulties and challenges during subsequent implementation of the Standard was summarized and outlined simultaneously, so as to provide a guarantee for users to fully comprehend and effectively implement the Standard.

Background Agitated behaviour in male patients with schizophrenia can lead to serious consequences for the individual and the society.Non-invasive drug delivery may help to rapidly control agitation and improve the overall patient satisfaction,but there are limited studies on the efficacy of olanzapine oral soluble film for the treatment of agitated behaviour in patients with schizophrenia.Objective To compare the efficacy and safety profile of olanzapine oral soluble film versus intramuscular haloperidol against agitated behaviour in male patients with schizophrenia,so as to provide a reference for the treatment of agitated behaviour.Methods From May 2022 to July 2023,a consecutive sample of schizophrenic patients(n=44)with agitated behaviour who met the Diagnostic and Statistical Manual of Mental Disorders,fifth edition(DSM-5)were recruited in the male psychiatric closed ward of the Third People's Hospital of Fuyang.Patients were assigned into two groups using the random number table method,each with 22 cases.Study group was treated with olanzapine oral soluble film 10 mg/d,while control group was given intramuscular haloperidol 8 mg/d.The severity of agitated behaviour was determined using Positive and Negative Syndrome Scale-Excited Component(PANSS-EC)and Agitation Calmness Evaluation Scale(ACES)at the baseline and after 6 h of drug administration.The treatment response rate was calculated based on the reduction of PANSS-EC score,and the drug side effects were assessed using Rating Scale for Extrapyramidal Side Effects(RSESE)and Barnes Akathisia Rating Scale(BARS)after 6 h of drug administration.Results After 6 h of drug administration,no statistical difference was reported in PANSS-EC score and ACES score between two groups(F=0.039,0.082,P>0.05),and the treatment response rate yielded no statistical difference between two groups(χ2=0.419,P=0.517),while study group reported a lower incidence rate of adverse reactions compared with control group,with statistically significant difference(P=0.031).BARS scores noted no statistical significant difference between two groups(t=0.587,P=0.561),whereas study group scored lower on RSES compared to control group,with a statistical difference(t=-7.367,P<0.01).Conclusion In the treatment of agitation in male patients with schizophrenia,the efficacy of olanzapine oral soluble film is comparable to that of intramuscular haloperidol,while the safety profile of the former is superior to that of the latter.

Background Improper settings of outdoor smoking points in public places may increase the risk of secondhand smoke exposure among the population. Conducting research on air pollution in and around smoking spots and related influencing factors can provide valuable insights for optimizing the setting of outdoor smoking points. Objective To investigate the influence of the number of smokers at outdoor smoking points and the distance on the diffusion characteristics of surrounding air pollutants, in order to optimize the setting of outdoor smoking points. Methods Surrounding the exhibition halls in the China International Import Expo (CIIE), two outdoor smoking points were randomly selected, one on the first floor (ground level) and the other on the second floor (16 m above ground), respectively. At 0, 3, 6, and 9 m from the smoking points in the same direction, validated portable air pollutant monitors were used to measure the real-time fine particulate matter (PM_2.5) and carbon dioxide (CO₂) concentrations for consecutive 5 d during the exhibition, as well as the environmental meteorological factors at 0 m with weather meters including wind speed, wind direction, and air pressure. An open outdoor atmospheric background sampling point was selected on each of the two floors to carry out parallel sampling. Simultaneously, the number of smokers at each smoking point were double recorded per minute. The relationships between the number of smokers, distance from the smoking points, and ambient PM_2.5 and CO₂ concentrations were evaluated by generalized additive regression models for time-series data after adjustment of confounders such as temperature, relative humidity, and wind speed. Results The median numbers of smokers at smoking points on the first and second floors were 6 [interquartile range (IQR): 3, 9] and 9 (IQR: 6, 13), respectively. Windless (wind speed <0.6 m·s⁻¹) occupied most of the time (85.9%) at both locations. The average concentration of ambient PM_2.5 at the smoking points (0 m) [mean ± standard deviation, (106±114) μg·m⁻³] was 4.2 times higher than that of the atmospheric background [(25±7) μg·m⁻³], the PM_2.5 concentration showed a gradient decline with the increase of distance from the smoking points, and the average PM_2.5 concentration at 9 m points [(35±22) μg·m⁻³] was close to the background level (1.4 times higher). The maximum concentration of CO₂ [(628±23) μmol·mol⁻¹] was observed at 0 m, and its average value was 1.3 times higher than that of the atmospheric background [(481±40) μmol·mol⁻¹], and there was no gradient decrease in CO₂ concentration with increasing distance at 0, 3, 6, and 9 m points. The regression analyses showed that, taking smoking point as the reference, every 3 m increase in distance was associated with a decrease of ambient PM_2.5 by 24.6 [95% confidence interval (95%CI): 23.5, 25.8] μg·m⁻³ (23.2%) and CO₂ by 54.1 (95%CI: 53.1, 55.1) μmol·mol⁻¹ (8.6%). Every one extra smoker at the smoking point was associated with an average increase of PM_2.5 and CO₂ by 2.0 (95%CI: 1.7, 2.8) μg·m⁻³ and 1.0 (95%CI: 0.7，1.2) μmol·mol⁻¹, respectively. The sensitivity analysis indicated that, under windless conditions, the concentrations of PM_2.5 and CO₂ at the smoking points were even higher but the decreasing and dispersion characteristics remained consistent. Conclusion Outdoor smoking points could significantly increase the PM_2.5 concentrations in the surrounding air and the risks of secondhand smoke exposure, despite of the noticeable decreasing trend with increasing distance. Considering the inevitable poor dispersion conditions such as windless and light wind, outdoor smoking points are recommended to be set at least 9 m or farther away from non-smoking areas.

Objective:To investigate the impact of early removal of nasogastric tubes on functional recovery after total gastrectomy for gastric cancer patients, to provide scientific evidence for enhanced recovery after surgery strategies in gastric cancer.Methods:A retrospective cohort study was conducted on 102 gastric cancer patients who underwent total gastrectomy at Beijing Friendship Hospital affiliated with the Capital Medical University from March 2018 to July 2022. Patients were divided into two groups based on whether the gastric tube was removed within 24 hours post-operation: the early removal group (within 24 hours, 55 patients) and the non-early removal group (beyond 24 hours, 47 patients). The recovery outcomes, including time to first flatus, time to fluid intake, length of hospital stay, and the incidence of postoperative complications, were compared between the two groups. Non-normally distributed data were expressed as M( Q1, Q3) and compared using the Wilcoxon rank-sum test. Categorical data were expressed as frequencies or percentages and compared using the chi-square test or Fisher′s exact test. To minimize the impact of potential confounders, multivariable linear regression and logistic regression analyses adjusted for propensity scores were further employed to compare quantitative and qualitative data between the groups. Statistical analyses were performed using R software. Results:The exhaust time, water intake time, and hospital stay in the early removal group were 3.0(2.0, 3.5) days, 4.0(3.0, 5.0) days, and 7.0(7.0, 8.0) days, respectively, while those in the non-early removal group were 4.0(3.0, 5.0) days, 6.0(5.0, 7.0) days, and 8.0(7.5, 11.0) days, respectively. Statistically significant differences were observed between the two groups ( P<0.05). However, there was no significant difference in the incidence of postoperative complications between the two groups (5.45% vs 17.02%, P=0.060). Propensity score-adjusted regression analysis suggested that early tube removal might reduce the risk of postoperative complications ( P=0.042). Conclusion:Early removal of nasogastric tubes can significantly accelerate functional recovery after total gastrectomy for gastric cancer patients and may reduce the risk of postoperative complications, providing important clinical guidance for enhanced recovery after surgery management in gastric cancer.