BACKGROUND:Previous studies have found that neuronal damage caused by continuous excessive fluoride exposure is related to Ca2+overload,but the mechanism of Ca2+flow conversion between intracellular calcium stores and cell apoptosis damage is still unclear.OBJECTIVE:To investigate the effect of fluoride exposure on Ca2+transport channel proteins and apoptosis levels in the mitochondria-associated endoplasmic reticulum membrane of primary cultured neural cells.METHODS:Primary nerve cells of neonatal SD rats were cultured in vitro and identified by immunofluorescence staining with neuronal nucleus-specific antibody up to day 7.The nerve cells were divided into control group(containing 0 mmol/L sodium fluoride),low fluoride group(containing 0.5 mmol/L sodium fluoride),and high fluoride group(containing 1 mmol/L sodium fluoride).The cell morphological changes were observed by light microscope 24 hours after fluorine exposure.The expression levels of apoptosis-related protein BAX/BCL-2 and calcium transfer-related pathways VDAC1,GRP 75,and IP3R were detected using western blot assay.The expression levels of VDAC1,GRP 75,and IP3R mRNA were detected by RT-PCR.Ca2+levels were detected by Rhood-2AM Ca2+probe.Mitochondrial membrane potential detection kit was used to detect the change in mitochondrial membrane potential.The level of apoptosis was determined by flow cytometry and TUNEL staining.RESULTS AND CONCLUSION:(1)The purity of neurons cultured on day 7 had been determined to be over 90％,with few impurities,good growth status,and tight cell network connections,meeting the requirements of subsequent experiments.(2)Compared with the control group,growth of neural cell clusters in the low-fluoride group and the high-fluoride group increased;the processes were broken;the cell body was rounded,and the connection network between cells was destroyed.Compared with the low-fluoride group,the cell damage changes in the high-fluoride group were more obvious.(3)Compared with the control group,the protein expressions of VDAC1,GRP75,and IP3R were increased in the low-fluoride group and the high-fluoride group(P＜0.05),and the ratio of apoptosis-related protein BAX/BCL-2 was increased(P＜0.05).Compared with the control group,the expression of VDAC1 and GRP75 mRNA in the low-fluoride group was significantly increased(P＜0.05);the expression levels of VDAC1,GRP75,and IP3R mRNA in the high-fluoride group were significantly increased(P＜0.01).(4)The level of cell apoptosis increased significantly after fluoride exposure,and the high-fluoride group was significantly higher than the control and low-fluoride groups(P＜0.01).(5)After fluoride exposure,the concentration of mitochondrial Ca2+in nerve cells increased significantly(P＜0.05),the mitochondrial membrane potential decreased(P＜0.01),and the degree of damage in the high-fluoride group was more obvious(P＜0.05).The results show that fluoride exposure impairs the morphological structure of primary neural cells,resulting in upregulation of Ca2+transfer pathway protein expression between the endoplasmic reticulum and mitochondria,mitochondrial Ca2+overload,mitochondrial damage,and increased levels of apoptosis.

BACKGROUND:Previous studies have found that neuronal damage caused by continuous excessive fluoride exposure is related to Ca2+overload,but the mechanism of Ca2+flow conversion between intracellular calcium stores and cell apoptosis damage is still unclear.OBJECTIVE:To investigate the effect of fluoride exposure on Ca2+transport channel proteins and apoptosis levels in the mitochondria-associated endoplasmic reticulum membrane of primary cultured neural cells.METHODS:Primary nerve cells of neonatal SD rats were cultured in vitro and identified by immunofluorescence staining with neuronal nucleus-specific antibody up to day 7.The nerve cells were divided into control group(containing 0 mmol/L sodium fluoride),low fluoride group(containing 0.5 mmol/L sodium fluoride),and high fluoride group(containing 1 mmol/L sodium fluoride).The cell morphological changes were observed by light microscope 24 hours after fluorine exposure.The expression levels of apoptosis-related protein BAX/BCL-2 and calcium transfer-related pathways VDAC1,GRP 75,and IP3R were detected using western blot assay.The expression levels of VDAC1,GRP 75,and IP3R mRNA were detected by RT-PCR.Ca2+levels were detected by Rhood-2AM Ca2+probe.Mitochondrial membrane potential detection kit was used to detect the change in mitochondrial membrane potential.The level of apoptosis was determined by flow cytometry and TUNEL staining.RESULTS AND CONCLUSION:(1)The purity of neurons cultured on day 7 had been determined to be over 90％,with few impurities,good growth status,and tight cell network connections,meeting the requirements of subsequent experiments.(2)Compared with the control group,growth of neural cell clusters in the low-fluoride group and the high-fluoride group increased;the processes were broken;the cell body was rounded,and the connection network between cells was destroyed.Compared with the low-fluoride group,the cell damage changes in the high-fluoride group were more obvious.(3)Compared with the control group,the protein expressions of VDAC1,GRP75,and IP3R were increased in the low-fluoride group and the high-fluoride group(P＜0.05),and the ratio of apoptosis-related protein BAX/BCL-2 was increased(P＜0.05).Compared with the control group,the expression of VDAC1 and GRP75 mRNA in the low-fluoride group was significantly increased(P＜0.05);the expression levels of VDAC1,GRP75,and IP3R mRNA in the high-fluoride group were significantly increased(P＜0.01).(4)The level of cell apoptosis increased significantly after fluoride exposure,and the high-fluoride group was significantly higher than the control and low-fluoride groups(P＜0.01).(5)After fluoride exposure,the concentration of mitochondrial Ca2+in nerve cells increased significantly(P＜0.05),the mitochondrial membrane potential decreased(P＜0.01),and the degree of damage in the high-fluoride group was more obvious(P＜0.05).The results show that fluoride exposure impairs the morphological structure of primary neural cells,resulting in upregulation of Ca2+transfer pathway protein expression between the endoplasmic reticulum and mitochondria,mitochondrial Ca2+overload,mitochondrial damage,and increased levels of apoptosis.

Recent studies have shown that the physiological homeostasis of oral mucosal cells is regulated by the circadian clock.Dis-ruption or dysfunction of the circadian clock is closely associated with the development of oral squamous cell carcinoma(OSCC).Research based on the circadian clock offers a novel perspective on the pathogenesis and therapeutic strategies for OSCC.However,there is current-ly limited research on this topic,and people generally have insufficient understanding and recognition of the circadian clock.Given the complexity and challenges of circadian clock which is the fourth dimension of medical research,we organize relevant experts based on summarizing the current research results of circadian clock in the pathogenesis and precision diagnosis and treatment of OSCC,combining the scientific principles of the circadian clock's role and their long-term research experience,then summarizes and recommends the con-sensus opinions for the research of circadian clock in the pathogenesis mechanism and precision diagnosis and treatment of human OSCC,with the hope of providing guidance for the basic research and clinical application of circadian clock or circadian rhythm in the pathogene-sis mechanism and precision diagnosis and treatment of oral and maxillofacial squamous cell carcinoma.

Recent studies have shown that the physiological homeostasis of oral mucosal cells is regulated by the circadian clock.Dis-ruption or dysfunction of the circadian clock is closely associated with the development of oral squamous cell carcinoma(OSCC).Research based on the circadian clock offers a novel perspective on the pathogenesis and therapeutic strategies for OSCC.However,there is current-ly limited research on this topic,and people generally have insufficient understanding and recognition of the circadian clock.Given the complexity and challenges of circadian clock which is the fourth dimension of medical research,we organize relevant experts based on summarizing the current research results of circadian clock in the pathogenesis and precision diagnosis and treatment of OSCC,combining the scientific principles of the circadian clock's role and their long-term research experience,then summarizes and recommends the con-sensus opinions for the research of circadian clock in the pathogenesis mechanism and precision diagnosis and treatment of human OSCC,with the hope of providing guidance for the basic research and clinical application of circadian clock or circadian rhythm in the pathogene-sis mechanism and precision diagnosis and treatment of oral and maxillofacial squamous cell carcinoma.

Objective To investigate the protective effect of human amniotic mesenchymal stem cells(hAMSCs)on pulmonary microvascular endothelial cell(PMVECs)through observing the effects of prolifer-ation,apoptosis and inflammatory response after PMVECs injury induced by pine sawdust smoke solution.Methods HAMSCs and rat PMVECs were isolated and cultured.The flow cytometry and immunofluores-cence were used to identify hAMSCs and PMVECs respectively.The experimental grouping:control group(normal cultured PMVECs),smoke group(PMVECs injury induced by pine sawdust smoke solution),smoke+hAMSCs group(after PMVECs was injured by smoke solution,hAMSCs and PMVECs were co-cul-tured in Transwell culture system).The proliferative activity of PMVECs after co-culture for 12,24 h was measured by cell counting kit-8(CCK-8),the apoptosis of PMVECs was measured by flow cytometry,and the ex-pression levels of TNF-α and IL-6 were detected by enzyme-linked immunosorbent assay(ELISA).Results hAMSCs and PMVECs were successfully isolated and cultured,and the hAMSCs surface markers CD105(95.4％),CD73(99.8％)and CD90(99.8％)were identified as strongly positive expression,while CD34,CD45,CD14,CD19 and HLA-DR were weakly expressed(1.96％in total).The vascular endothelial cell mark-er CD34 in PMVECs was positively expressed,moreover its combination with aggulutinin BSI was also posi-tive.At the observation time point of 12,24 h co-culture,compared with the Control group,the proliferation activity of PMVECs in the Smoke group was inhibited(P＜0.05),and the cellular apoptosis was increased(P＜0.05),the TNF-α and IL-6 expression levels were up-regulated(P＜0.05);the phenomena of PMVECs proliferation activity inhibition,apoptosis increase and inflammatory factor expression level up-regulation in the Smoke+hAMSCs group were reversed compared with the Smoke group(P＜0.05).Conclusion After PMVECs are injured by smoke solution,hAMSCs could decrease the PMVECs inflammatory factors expres-sion,promote its proliferation activity and inhibit its apoptosis,thus play the protective effect on PMVECs.

【Objective】 To investigate the mechanism of pristane inducing autophagy in macrophages. 【Methods】 Pristane was used to stimulate NR8383， a rat macrophage cell line. The changes in signaling pathways of AMPK， mTOR， and endoplasmic reticulum （ER） stress pathways including eIF2α and IRE1α in the cell model， as well as the expression of transcriptional factor TFEB and its translocation to the nucleus， were detected by using Western blotting. ER stress pathways were intervened by using an inducer DTT or an inhibitor 4-PBA to determin its effect on mTOR expression and autophay. 【Results】 In pristane-stimulated NR8383 cell model， ER stress pathway eIF2α was activated at 0.5 h after stimulation， and then mTOR expression was decreased at 1 and 3 h after stimulation. There was no change for AMPK and IRE1α pathways. With 4-PBA treatment， pristane-reduced mTOR expression and increased LC3-II were reversed， while with DTT treatment， mTOR expression decreased and LC3-II expression increased even more. Pristane induced the expression and activation of TFEB in NR8383 cells. 【Conclusion】 Pristane induces ER stress and leads to autophagy enhancement in rat macrophages.

Abstract: To investigate the changes of cerebral blood flow(CBF) in patients with type 2 diabetes mellitus(T2 DM) and its correlation with cognitive function and olfactory impairment. Methods: Cognitive function assessment and smell identification test were performed on 83 patients with T2 DM and 62 healthy controls(HC). Three-dimensional pseudo-continuous arterial spin labeling(3 D-pcASL) head images were collected from the two groups. CBF values of the cerebral cortex were compared between the patients and HC after the postprocessing. Correlations between the CBF values and cognitive function assessment and between the CBF values and smell identification test scores were analyzed as well. Results: Compared to the HC, Chinese smell identification test(CSIT), montreal cognitive assessment(MoCA), digit span test(DST), verbal fluency test(VFT) scores were lower in T2 DM patients(P<0.05).The CBF of the bilateral middle frontal gyrus in T2 DM patients was higher than that in HC group(P<0.001). The CBF of the bilateral gyrus rectus and olfactory cortex in T2 DM patients was lower than that in HC group(P<0.001). Conclusion The cognitive and olfactory function of patients with T2 DM decreased. Patients with T2 DM have abnormal perfusion in the bilateral middle frontal gyrus, gyrus rectus and olfactory cortex, revealing that CBF changes in these brain regions may be one of the causes for cognitive impairment and olfactory dysfunction in T2 DM.

Objective:To investigate the role of survival motor neuron ( SMN) gene knockout in mice with cisplatin-induced acute kidney injury (AKI). Methods:A mouse model (C57BL/6) of cisplatin-induced AKI was constructed. Twenty male wild type (WT) and SMN+/- mice weighing 22-24 g were randomly divided into four groups: WT mice with saline injection group (WT vehicle, n=5), SMN+/- mice with saline injection group ( SMN+/- vehicle, n=5), WT mice with cisplatin injection group (WT cisplatin, n=5) and SMN+/- mice with cisplatin injection group ( SMN+/- cisplatin, n=5). Mice were injected intraperitoneally with 20 mg/kg cisplatin or 0.9% saline. 72 hours later, the mice were sacrificed, and serum and kidney tissues were collected. The real time PCR and Western blotting were used to measure the expression levels of SMN mRNA and protein. The sarcosine oxidation and urease method were used to measure serum creatinine (Scr) and blood urea nitrogen (BUN) levels. Renal pathologic changes were observed by PAS staining. TUNEL immunofluorescence assay was used to detect the level of apoptosis. Western blotting and immunohistochemistry were used to detect the protein expression levels of apoptosis index poly (ADP-ribose) polymerase (PARP) and endoplasmic reticulum stress index CHOP. Results:Compared with WT mice, SMN mRNA and protein expression levels were lower in SMN+/- mice, and the expression level of SMN mRNA and protein was further decreased after intraperitoneal cisplatin injection (all P<0.05). Compared with WT mice with saline injection group, WT mice with cisplatin injection group had higher levels of Scr, BUN, tubular damage scores, TUNEL positive cell numbers, PARP and CHOP, while the expression levels of above indexes in the SMN+/- mice with cisplatin injection group were higher than those in the WT mice with cisplatin injection group (all P<0.05). Conclusions:SMN gene knockout can aggravate renal pathological damage and apoptosis of renal tubular epithelial cell in cisplatin-induced AKI mice. SMN may be a potential therapeutic target of AKI.

Objective:To explore the sex-based heterogeneity in demographic and pathological trends of lung cancer during the past 30 years.Methods:Patients with primary lung cancer who received surgical treatment in the Department of thoracic surgery, Shanghai Pulmonary Hospital Tongji University from 1989 to 2018 were retrospectively analyzed. The differences between male and female patients in age, smoking history, pathological stage and type were compared. Mann- Kendall trend test was performed for trend analysis. Results:A total of 58 433 patients were included in this study, encompassing 30 729(52.6%) men and 27 , 704(47.4%) women. Compared with male patients, female patients were younger(56.0 years old vs. 59.7 years old), and had a higher proportion of non-smokers(98.3% vs. 52.3%), stage Ⅰ lung cancers(60.6% vs. 49.3%), and adenocarcinoma(93.7% vs. 56.1%, all P-values <0.001). Trend analyses revealed that the proportion of female patients increased year by year, and surpassed males in 2015, with the current ratio of male to female being 1∶1.5. After 2013, the age of onset in females was getting younger, and the average age decreased from 58.7 years old to 54.7 years old( P=0.02). The decrease in the proportion of smoking patients was mainly reflected by male patients(from 68.5% to 31.1%, P<0.01). Stage Ⅰ lung cancers in male and females outnumbered advanced stage in 2012 and 2010, respectively, with a much higher proportion in female patients. Among male patients, adenocarcinoma has replaced squamous cell carcinoma as the most common pathological type since 2012, while in female patients adenocarcinoma remained the most common pathological type of lung cancer, and its proportion continued to increase reaching over 98%. Conclusion:A dramatic change in gender distribution was noticed during the past 30 years. Female patients became the primary population in surgically-treated lung cancers, with a trend of getting younger. The proportion of smokers and squamous cell carcinoma decreased significantly in male patients, and adenocarcinoma has become the most common pathological type of lung cancer. The proportion of stage Ⅰ lung cancers was on a dramatic rise, with the popularization of CT screening for lung cancer.

Objective:To analyze the clinical characteristics of adult Chinese patients with syncope.Methods:This is a cross-sectional survey study. Patients with preliminary diagnosis of syncope in the Emergency Department, Geriatrics and Cardiology Outpatient Department, or Syncope Unit of 37 hospitals in 19 provinces, autonomous regions and the Hong Kong Special Administrative Region from June 2018 to March 2021 were included in this study. The clinical features of these patients with syncope were analyzed.Results:A total of 4 950 consecutive patients with syncope were included in this study. The age was (56.3±16.8)years, and 2 604 cases (52.6%) were male. The most common type of syncope was neurally mediated syncope (2 345 (47.4%)), followed by cardiac syncope (1 085 (21.9%)), orthostatic hypotensive syncope (311 (6.3%)), and unexplained syncope accounted for nearly one third (1 155 (23.3%)). Predisposing syncope was more common in patients under 65 years of age(2 066(72.4%) vs. 786(27.6%),χ 2=136.5, P<0.001). Presyncope was more common in patients with neurally mediated syncope (1 972(79.0%) vs.1 908(73.9%), χ 2=17.756, P<0.001). Premonitory symptoms were more common in women(1 837(80.0%) vs. 1 863(73.0%),χ 2=33.432, P<0.001). Presyncope syndrome was more common in patients under 65 years of age (2 482(77.8%) vs. 1 218(73.4%),χ 2=17.523, P=0.001). Cyanosis was more common in ≥65 years old patients (271(18.2%) vs. 369(12.7%), χ 2=23.235, P<0.001). Urinary incontinence was more common in old patients aged ≥65 years(252(15.2%) vs. 345(10.8%), χ 2=19.313, P<0.001). Family history was more common in patients with cardiogenic syncope compared with other types of syncope (264(24.3%) vs. 754(19.5%), χ 2=11.899, P=0.001). Hypertention(1 480(30.5%)), coronary heart disease(1 057(21.4%)), atrial flutter and atrial fibrillation(359(7.2%)), second degree atrioventricular block(236(4.8%)) were common complications of syncope. The proportion of patients with coronary heart disease was significantly higher in cardiac syncope than that of other types of syncope(417(38.4%) vs. 640(16.6%), χ 2=241.376, P<0.001). Other common complications included cerebrovascular diseases (551 (11.1%)) and diabetes mellitus (632(12.8%)). Conclusions:Neurally mediated syncope is the most common syncope in adult Chinese population. Patients with predisposing conditions and premonitory conditions are younger. Presyncope is more common in women. The proportion of family history and coronary heart disease is higher in patients with cardiogenic syncope.