Case report: A lung squamous cell carcinoma patient with a rare EGFR G719X mutation and high PD-L1 expression showed a good response to anti-PD1 therapy.

Lung cancer treatment has transitioned fully into the era of immunotherapy, yielding substantial improvements in survival rate for patients with advanced non-small cell lung cancer (NSCLC). In this report, we present a case featuring a rare epidermal growth factor receptor (EGFR) mutation accompanied by high programmed death-ligand 1 (PD-L1) expression, demonstrating remarkable therapeutic efficacy through a combination of immunotherapy and chemotherapy. A 77-year-old male with no family history of cancer suffered from upper abdominal pain for more than half months in August 2020 and was diagnosed with stage IV (cT3N3M1c) lung squamous cell carcinoma (LUSC) harboring both a rare EGFR p.G719C mutation and high expression of PD-L1 (tumor proportion score [TPS] = 90%). Treatment with the second-generation targeted therapy drug Afatinib was initiated on September 25, 2020. However, resistance ensued after 1.5 months of treatment. On November 17, 2020, immunotherapy was combined with chemotherapy (Sintilimab + Albumin-bound paclitaxel + Cisplatin), and a CT scan conducted three months later revealed significant tumor regression with a favorable therapeutic effect. Subsequently, the patient received one year of maintenance therapy with Sintilimab, with follow-up CT scans demonstrating subtle tumor shrinkage (stable disease). This case provides evidence for the feasibility and efficacy of immunotherapy combined with chemotherapy in the treatment of EGFR-mutated and PD-L1 highly expressed LUSC.

[Correlation Between Controlling Nutritional Status Scores and Amputation Risks in Patients with Diabetic Foot Ulcers].

Objective: To retrospectively analyze the clinical features and treatment outcomes of patients with diabetic foot ulcers (DFU), and to investigate the effect of controlling nutritional status (CONUT) scores on the amputation risks and hospital length-of-stay of DFU patients. Methods: A total of 357 DFU inpatients admitted to the Department of Endocrinology, PLA Strategic Support Force Characteristic Medical Center between January 1, 2016 and December 31, 2018 were enrolled and analyzed retrospectively. Based on their CONUT scores, the patients were divided into 3 groups, a normal nutritional status group consisting of patients with CONUT scores 0-1 ( n=100), a mild malnutrition group consisting of patients with CONUT scores 2-4 scores ( n=164), and a moderate-to-severe malnutrition group consisting of patients with CONUT scores≥5 ( n=93). According to whether they underwent amputation, patients were divided into an amputation group ( n=110) and a non-amputation group ( n=247). The clinical characteristics, amputation rate, and hospital length-of-stay were compared between groups with different CONUT scores. Logistic regression was conducted to analyze the independent risk factors of amputation. Results: The total amputation rate of DFU patients was 30.6%. Among all amputations, the major amputation (above-the-ankle amputation) rate was 1.8%, and the minor amputation rate was 98.2%. The amputation rate in patients with mild and moderate-to-severe malnutrition were 1.5 and 3.0 times higher than those in the normal nutritional status group, respectively. Logistic regression analysis showed that the moderate-to-severe nutritional status (5-12 scores), white blood cell, Wagner classification and ankle-brachial index were independent risk factors for amputation. Conclusion: CONUT score is closely associated with amputations in DFU patients. Improving the nutritional status of patients in the early stage could reduce the risk of amputation.

Analgesic effect of auricular point acupressure for acute pain in patients with dementia: study protocol for a randomized controlled trial.

BACKGROUND: Common and frequent as acute pain is, it is often underestimated and undertreated in older people with dementia in nursing homes and inadequate pain management remains an issue. METHODS: The study is designed to be a randomized, sham-controlled trial and is underway in nursing homes located in China. A total of 206 dementia patients are being recruited from nursing homes in Yinchuan, China. They are randomly allocated to an intervention or a controlled group in a 1:1 ratio. The intervention group will be treated with true APP therapy, while the other group will receive APP at sham point stimulation therapy. The patients will be assessed at baseline (T0), at 5 min during performing the intervention (T1), and at 5 min after completion of the intervention (T2). The primary outcome is the level of pain relief at T1 and T2. Physiological parameters, side effects and additional use of analgesics during the procedure, satisfaction from caregivers, and acceptance of patients are evaluated as secondary outcomes. DISCUSSION: The results of this study are expected to verify the analgesic effect of APP for acute pain in patients with mild dementia in nursing homes. It has the potential to prompt APP therapy to be implemented widely in dementia patients with acute pain in nursing homes. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2100047932 . Registered on 27 June 2021. Currently, patient recruitment is ongoing. Recruitment is expected to take place from December 2020 to December 2021.

The mediator role of stigma in the association of mindfulness and social engagement among breast cancer survivors in China.

PURPOSE: This study aims to explore the association between mindfulness and social engagement among Chinese breast cancer survivors (BCSs) and the mediator role of stigma in the relation of mindfulness and social engagement. METHODS: This cross-sectional study was conducted among 937 BCSs from March to April 2021 in Shanghai, China. Data were collected using the Mindful Attention Awareness Scale, the Stigma Scale for Chronic Illness 8-item version, and the index of social engagement. Descriptive statistics, independent-sample t-test, one-way ANOVA, and regression analyses were used to explore the role of stigma in the association of mindfulness and social engagement among Chinese BCSs. RESULTS: Social engagement levels differed significantly by participant's BMI, education level, employment status, personal monthly income, monthly per capita household income. Mindfulness was positively correlated with social engagement, and stigma was negatively correlated with mindfulness and social engagement among Chinese BCSs. Stigma plays a complete mediating role in the relationship between mindfulness and social engagement in BCSs. CONCLUSION: In the practice of individual mindfulness intervention on social engagement of BCSs, health care providers should identify and eliminate the constraints, which restrain the reduction of stigma level while individual mindfulness is being enhanced.

Spin-Dependent Polaron Dynamics in Organic Ferromagnets.

The spin-dependent polaron dynamics in organic ferromagnets under driven electric fields are investigated by using the extended Su-Schrieffer-Heeger (SSH) model coupled with a nonadiabatic dynamics method. It is found that the spin-down polaron with the same spin orientation as the radicals drifts faster than the spin-up one under the same driven electric field. In an applicable range of driven electric fields, the velocity of the spin-down polaron is about 3.4 times that of the spin-up one. The dynamical property of the polaron with each spin (up or down) is asymmetric upon the reversal of the driven electric fields. The diverse dynamical properties of polarons with specific spins can be attributed to the spin nondegenerate polaron energy levels, the dipole moment generated by the asymmetrical polaron charge distributions and the strong electron-lattice coupling in organic ferromagnets. Our findings are expected to be useful for improving organic ferromagnet based spintronic devices.

Optimization and feedback control system of dilution rate for 1,3-propanediol in two-stage fermentation: A theoretical study.

In utilizing glycerol to produce 1,3-propanediol by microbial fermentation, the problems of low utilization rate and poor production performance need to be addressed. Based on the analysis of a mathematical model for 1,3-propanediol production from glycerol by Klebsiella pneumoniae, this study theoretically investigated the effects of the dilution rate and the initial glycerol concentration in a two-stage fermentation process and the feasibility of applying the feedback control methods. First, the optimal operation conditions of initial glycerol concentration and dilution rate were obtained. Through the use of feedback control theory, a control strategy for dilution rate was designed and optimized to shorten the settling time (time required for fermentation to reach stability) from 60.92 to 36.68 h for the first reactor, and from 53.66 to 22.68 h for the second reactor. In addition, the yield of 1,3-propanediol in both two reactors reached up to 0.5 g·g-1 . The simulation results indicated that the feedback control strategy for dilution rate increased the product concentration, reduced the residual glycerol in the fermentation broth, and greatly improved the performance of the fermentation. A feeding strategy of automatic control for dilution rate has been established and will be applied as an effective guiding scheme in automatic continuous fermentations for production of 1,3-propanediol.

First record of disk-footed bat Eudiscopus denticulus (Chiroptera, Vespertilionidae) from China and resolution of phylogenetic position of the genus.

The disk-footed bat Eudiscopus denticulus(Osgood, 1932) is a rare species in Southeast Asia. During two chiropteran surveys in the summer of 1981 and 2019, eight and three small Myotis-like bats with distinct disk-like hindfeet were collected from Yunnan Province, China, respectively. External, craniodental, and phylogenetic evidence confirmed these specimens as E. denticulus, representing a new genus in China. The complete mitochondrial genome consistently showed robust support for E. denticulus as a basal lineage within Myotinae. The coding patterns and characteristics of its mitochondrial genome were similar to that of other published genomes from Myotis. The echolocation signals of the newly collected individuals were analyzed. The potential distribution range of Eudiscopus in Southeast Asia inferred using the MaxEnt model indicated its potential occurrence along the southern border region of Yunnan, China.

Isolation and Genome Sequencing of a Novel Pseudomonas aeruginosa Phage PA-YS35.

Phage PA-YS35 is a novel lytic Pseudomonas aeruginosa phage belonging to the Myoviridae family and was isolated from the sewage of the First Hospital of Jilin University. The biological properties testing indicated that phage PA-YS35 is stable between - 20 and 60 °C and pH 4-9. The one-step growth curve shows that the latent period of PA-YS35 was 9 min, and the burst period was about 21 min by the size of approximately 380 progeny phages per host cell. The genome of phage PA-YS35 is linear double-stranded DNA with a size of 93,296 bp and a GC content of 49.35%. The results from RAST gene annotation analysis showed that the PA-YS35 genome contains 172 open reading frames (ORFs); the function of 41 ORFs can be predicted, whereas the product of remaining 131 ORFs are hypothetical proteins. According to phylogenetic tree of RNA ligase encoding sequence, phage PA-YS35 has a close evolutionary relationship with Pseudomonas phage PAK P1 because both of them are located on the same branch. The study of phage PA-YS35 genome will provide useful information for further research on the interaction between phages and their hosts.

Ensemble optimization of microbial conversion of glycerol into 1, 3-propanediol by Klebsiella pneumoniae.

Using mathematical model and computer simulation to predict biological processes and optimize the target production is an important strategy for optimizing fermentation process. However, the inherent uncertainty of the kinetic model severely limits the predictive capability. In this study, optimize target production, such as productivity and yield of 1, 3-propanediol produced by Klebsiella pneumoniae using glycerol as substrate, the ensemble modeling approach was used to reduce the model's uncertainty for fermentation process as much as possible, and effectively improve its prediction performance. Firstly, through sensitivity analysis, the parameters having significant influence on the model were determined as the adjustable parameters for the ensemble modeling. After comparison, the appropriate threshold coefficient of the model error was determined, and the sampling method was used to generate as many equivalent parameter sets as possible. Each set of parameters was separately applied for the simulation, and all the predicted values were integrated for the weighted average. Therefore, the expected value of the prediction was obtained. Compared with the traditional simulation using single parameter set, the ensemble modeling method achieved the lower relative error between the prediction and the experimental value and the greatly improved model prediction performance. Moreover, the optimal productivity and yield of 1, 3-propanediol and the corresponding operating conditions were obtained, respectively. The ensemble modeling approach effectively compensates for the uncertainties of the model, making its prediction performance more practical, which is important for computer simulations to predict and guide the actual production process.

Dynamic flux balance analysis for microbial conversion of glycerol into 1,3-propanediol by Klebsiella pneumoniae.

To investigate the relationship between the yield of 1,3-propanediol (1,3-PD) and the flux variation in metabolic pathways of Klebsiella pneumoniae, an optimized calculation method was constructed on basis of dynamic flux balance analysis by combining genome-scale flux balance analysis with a kinetic model of extracellular metabolites. Through optimizing calculations, a more completely expanded metabolic pathway was obtained, which includes the previously reported metabolic pathway and additional three pathways or site: a pentose phosphate pathway (PPP) elicited at the dihydroxyacetone (DHA) node to provide more reducing equivalents; a branch of synthetic amino acids at the 3-phosphoglycerate (3PG) node; and the α-ketoglutarate site in the tricarboxylic acid (TCA) cycle leading to anabolic pathways for glutamate and other amino acids. On this basis, the relationships between the dynamic flux distribution of the important nodes in the metabolic pathway and the yield of 1,3-propanediol were analyzed. First, dynamic flux change from DHA to the PPP is positively correlated with the yield. Second, variation in flux in the TCA cycle is also positively correlated with the yield of 1,3-propanediol. In addition, the influence of the feedback loop formed by the cofactor tetrahydrofolate on the flux change of TCA in the amino acid anabolic pathway was examined. These results are of important reference value and have guiding significance for the extension of the glycerol metabolism pathway in K. pneumoniae, the rational transformation of genetic engineering in bacteria, and the optimization of metabolic pathways for industrial production.

Development of sandwich Enzyme-Linked Immunosorbent Assay for the detection of porcine epidemic diarrhea virus in fecal samples.

Porcine epidemic diarrhea virus (PEDV) causes acute diarrhea and dehydration in new-born piglets with subsequent economic losses to swine industry. In the current study, gene encoding of 381aa-792aa spike protein (S1) with the main epitope relative to virus neutralization of PEDV was amplified by RT-PCR and inserted into vector pET-30A(+). The plasmid was transferred into Escherichia coli BL21 (DE3). Meanwhile, recombinant protein expression was induced by isopropy1-ß-galactopyranoside (IPTG). After denaturation and renaturation of inclusion bodies, the S1 protein was obtained by using purified recombinant S1 protein in immunized female BALB/c mice. Monoclonal antibodies (MAb) against S1 protein, named 4C7 by hybridoma technique were gained successfully. The result showed that MAb can specifically respond to S1 protein and PEDV via ELISA, Western bolt and immunofluorescence assay methods. A sandwich ELISA (S-ELISA) was established by using the captured monoclonal antibodies 4C7. The sensitivity and specificity were compared between S-ELISA and RT-PCR, which showed similar sensitivity and specificity. This work indicated that S-ELISA would be a significant tool alongside a specific diagnostic reagent for PEDV in future.

[Survey on dental caries status of migrant children aged 6-12 years in Minhang district of Shanghai].

PURPOSE: To investigate the prevalence of dental caries among migrant children aged 6-12 years in Minhang district of Shanghai, so as to provide some basic data for children health care. METHODS: Ten thousand and eleven school children in 8 primary schools of Minhang district of Shanghai were investigated by cluster random sampling. Visual examination combined with probe inspection was used to diagnose caries, and then rate of caries and DMFT (decayed，missing and filled teeth) were calculated. SPSS 13.0 software package was used for statistical analysis. RESULTS: The prevalence of caries among children aged 6-12 years was 67.07%, which was significantly higher than that in children from government-owned schools (61.99%)(P<0.01). The prevalence of caries was 75.82% in 6-year-old group and highest compared to other groups. CONCLUSIONS: It can't be optimistic about the caries prevalence among migrant children aged 6-12 years in Minhang district，Shanghai.More attentions should be payed in prevention and early intervention of dental caries for children above 6 years old.

Mitochondrial Membrane Potential-dependent Endoplasmic Reticulum Fragmentation is an Important Step in Neuritic Degeneration.

BACKGROUND: Neuritic degeneration is an important early pathological step in neurodegeneration. AIM: The purpose of this study was to explore the mechanisms connecting neuritic degeneration to the functional and morphological remodeling of endoplasmic reticulum (ER) and mitochondria. METHODS: Here, we set up neuritic degeneration models by neurite cutting-induced neural degeneration in human-induced pluripotent stem cell-derived neurons. RESULTS: We found that neuritic ER becomes fragmented and forms complexes with mitochondria, which induces IP3R-dependent mitochondrial Ca(2+) elevation and dysfunction during neuritic degeneration. Furthermore, mitochondrial membrane potential is required for ER fragmentation and mitochondrial Ca(2+) elevation during neuritic degeneration. Mechanically, tightening of the ER-mitochondria associations by expression of a short "synthetic linker" and ER Ca(2+) releasing together could promote mitochondrial Ca(2+) elevation, dysfunction, and reactive oxygen species generation. CONCLUSION: Our study reveals a dynamic remodeling of the ER-mitochondria interface underlying neuritic degeneration.

[Determination of Flavonoids in Cycas revoluta Leaves by Chemiluminescence-Flow Injection Analysis Method].

OBJECTIVE: To detect flavonoids from Cycas revoluta leaves by means of Chemiluminescence-Flow Injection Analysis (CL-FIA). METHODS: Under alkaline condition, a CL-FIA method was established to determine flavonoids from leaves of Cycas revoluta on the basis of inhibiting effect of flavonoids to the Luminol-H2O2-Cu2+ chemiluminescence system and the reversed flow injection technique. RESULTS: In the range of 2. 0 x 10(-6) ~ 1. 0 x 10(-3) mg/mL, the decrease of CL intensity was correlated with flavonoids concentration while the detection limit was 0. 0265 µg/mL. Under the optimized conditions, the flavonoids of Cycas revoluta leaves were detected with its average rate reaching 1. 61% and RSD 1. 32%. CONCLUSION: Through the interference test and compared with the data of CL-FIA and UV, it is concluded that CL-FIA can be used in the analysis and detection of flavonoids from Cycas revoluta leaves.

Effects of allicin on the proliferation and cell cycle of chondrocytes.

The present study demonstrates the effect of allicin on the proliferation and the cell cycle distribution of the chondrocytes. MTT assay and flow cytometry were used for the evaluation of the effect of allicin on cell proliferative and the cell cycle distribution, respectively of the chondrocytes. The reverse transcription polymerase chain reaction (RT-PCR) and western blot analysis were respectively used for the analysis of mRNA and protein expression levels of cyclin D1, CDK4 and CDK6. The results revealed that exposure of the chondrocytes to allicin at a concentration of 40 µM significantly promoted the cell viability. Treatment of the cells with 10, 20, 30, 40, and 50 µg/mL of allicin enhanced the cell viability by 2.5.47 ± 0.86, 5.43 ± 0.66, 10.74 ± 1.48, 35.89 ± 3.78, and 32.21 ± 2.92%, respectively after 36 h compared to control cells. Allicin exposure caused a marked decrease in the percentage of cells in G0/G1 phase with a subsequent increase in the S phase population. Furthermore, allicin treatment enhanced the expression of cyclin D1, CDK4 and CDK6. Therefore, allicin treatment enhances the proliferation of chondrocytes by promoting the transition from G1 to S phase of the cell cycle through increase in the expression of cyclin D1, CDK4 and CDK6 levels.

Detection of genome-wide copy number variations in two chicken lines divergently selected for abdominal fat content.

BACKGROUND: The chicken (Gallus gallus) is an important model organism that bridges the evolutionary gap between mammals and other vertebrates. Copy number variations (CNVs) are a form of genomic structural variation widely distributed in the genome. CNV analysis has recently gained greater attention and momentum, as the identification of CNVs can contribute to a better understanding of traits important to both humans and other animals. To detect chicken CNVs, we genotyped 475 animals derived from two broiler chicken lines divergently selected for abdominal fat content using chicken 60 K SNP array, which is a high-throughput method widely used in chicken genomics studies. RESULTS: Using PennCNV algorithm, we detected 438 and 291 CNVs in the lean and fat lines, respectively, corresponding to 271 and 188 CNV regions (CNVRs), which were obtained by merging overlapping CNVs. Out of these CNVRs, 99% were confirmed also by the CNVPartition program. These CNVRs covered 40.26 and 30.60 Mb of the chicken genome in the lean and fat lines, respectively. Moreover, CNVRs included 176 loss, 68 gain and 27 both (i.e. loss and gain within the same region) events in the lean line, and 143 loss, 25 gain and 20 both events in the fat line. Ten CNVRs were chosen for the validation experiment using qPCR method, and all of them were confirmed in at least one qPCR assay. We found a total of 886 genes located within these CNVRs, and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses showed they could play various roles in a number of biological processes. Integrating the results of CNVRs, known quantitative trait loci (QTL) and selective sweeps for abdominal fat content suggested that some genes (including SLC9A3, GNAL, SPOCK3, ANXA10, HELIOS, MYLK, CCDC14, SPAG9, SOX5, VSNL1, SMC6, GEN1, MSGN1 and ZPAX) may be important for abdominal fat deposition in the chicken. CONCLUSIONS: Our study provided a genome-wide CNVR map of the chicken genome, thereby contributing to our understanding of genomic structural variations and their potential roles in abdominal fat content in the chicken.

Association of human papillomavirus L1 capsid protein with koilocytosis, expression of p16, and Ki-67, and its potential as a prognostic marker for cervical intraepithelial neoplasia.

OBJECTIVE: To study the relationship between human papillomavirus (HPV) L1 capsid protein (L1) and koilocytosis on ThinPrep cytology tests (TCTs) and the association of HPV L1 with p16 and Ki-67 expression in their corresponding biopsies. STUDY DESIGN: TCTs of 75 patients with high-risk HPV infection were studied for cytologic features of koilocytosis and for HPV L1 expression using combined detection of in situ hybridization and immunocytochemistry. All TCTs had follow-up biopsies on which p16 and Ki-67 were confirmed by immunostaining. RESULTS: Of 75 TCTs, 45 expressed HPV L1, while 23 displayed koilocytosis. All TCTs with koilocytosis expressed HPV L1. HPV L1 was lost in 23.3% of cervical intraepithelial neplasia (CIN) I, 16.7% of CIN II, and 60% of CIN III or higher (carcinoma in situ including suspected minor infiltration), categorized by biopsy, and the difference among CIN grades was statistically significant (chi2, p = 0.015). Expression scores of p16 and Ki-67 were higher in L1 negative cases than in positive cases (1.63 vs. 1.54 for p16; 1.53 vs. 1.32 for Ki-67); however, the difference was not significant (Mann-Whitney test: p = 0.57 for p16, p = 0.27 for Ki-67). CONCLUSION: HPV L1 expression was significantly associated with koilocytosis on TCT, and loss of L1 was associated with increase in CIN grade but not with p16 or Ki-67 expression. Our study suggests that HPV L1 is a more sensitive method than koilocytosis for detecting active HPV infection. Detection of HPV L1 on TCTs of high-risk HPV-infected patients can be helpful in risk assessment and prognostic prediction of CIN.

ANXA2 regulates the behavior of SGC-7901 cells.

ANXA2, a member of the annexin family, is overexpressed and plays important roles in tumor development. However, the significance of ANXA2 expression in gastric carcinoma has not been clarified.To elucidate its roles in growth of gastric cancer, ANXA2 expression in SGC-7901 cells was inhibited with a designated siRNA, then cell proliferation, cell cycling, apoptosis and motility were determined by MTT assay, flow cytometry, Hoechst 33342 staining and wound healing assay, respectively. To further assess the behavior of ANXA2 deleted SGC- 7901 cells, changes of microstructures were observed under fluorescence microscopy, laser scanning confocal microscopy and electron microscopy. We found that inhibition of ANXA2 expression caused cell proliferation to decrease significantly with G1 arrest, motility to be reduced with changes in pseudopodia/filopodia structure and F-actin and ß-tubulin expression, and apoptosis to be enhanced albeit without significance. At the same time, ANXA2 deletion resulted in fewer pseudopodia/filopodia, non-stained areas were increased, contact inhibition among cells reappeared, and expression of F-actin and ß-tubulin was decreased, with induction of polymerized disassembled forms. Taken together, these data suggest that ANXA2 overexpression is important to maintain the malignancy of cancer cells, and this member of the annexin family has potential to be considered as a target for the gene therapy of gastric carcinoma.

Identification of cellular proteome using two-dimensional difference gel electrophoresis in ST cells infected with transmissible gastroenteritis coronavirus.

BACKGROUND: Transmissible gastroenteritis coronavirus (TGEV) is an enteropathogenic coronavirus that causes diarrhea in pigs, which is correlated with high morbidity and mortality in suckling piglets. Information remains limited about the comparative protein expression of host cells in response to TGEV infection. In this study, cellular protein response to TGEV infection in swine testes (ST) cells was analyzed, using the proteomic method of two-dimensional difference gel electrophoresis (2D DIGE) coupled with MALDI-TOF-TOF/MS identification. RESULTS: 33 differentially expressed protein spots, of which 23 were up-regulated and 10 were down-regulated were identified. All the protein spots were successfully identified. The identified proteins were involved in the regulation of essential processes such as cellular structure and integrity, RNA processing, protein biosynthesis and modification, vesicle transport, signal transduction, and the mitochondrial pathway. Western blot analysis was used to validate the changes of alpha tubulin, keratin 19, and prohibitin during TGEV infection. CONCLUSIONS: To our knowledge, we have performed the first analysis of the proteomic changes in host cell during TGEV infection. 17 altered cellular proteins that differentially expressed in TGEV infection were identified. The present study provides protein-related information that should be useful for understanding the host cell response to TGEV infection and the underlying mechanism of TGEV replication and pathogenicity.

Role of endoplasmic reticulum stress in aberrant activation of fluoride-treated osteoblasts.

The aberrant activation of osteoblasts in the early stage is one of the critical steps during the pathogenesis of skeletal fluorosis. The endoplasmic reticulum (ER) stresses and unfolded protein response (UPR) are initiated to alleviate the accumulation of unfolded proteins against cell injury. The previous researches had demonstrated that fluoride induced ER stress in other cells or tissues. In this study, we determined the ER stress and UPR to investigate their roles in aberrant activation of fluoride-treated osteoblasts. The gene expression of bone markers and UPR factors in MC3T3-E1 cells treated with varying doses of fluoride administration was analyzed. Meantime, levels of glutathione and glutathione disulfide were tested by the ultraperformance liquid chromatography-tandem mass spectrometry applications. Our results indicated that a certain dose and period of fluoride administration induced cell proliferation and differentiation, and Runx2 was involved in the regulation of osteoblastic differentiation of MC3T3-E1 cells. Increase trend of Runx2 expression was consistent with change of marker of ER stress. Fluoride caused ER stress and stimulated UPR during the process of osteoblast maturation, while oxidative stress was also active in the occurrence of ER stress. These data indicated that ER stress and UPR were possibly involved in the action of fluoride on osteoblasts.