ObjectiveA middle cerebral artery occlusion (MCAO) mouse model is established by electrocoagulation of the middle cerebral artery. The study examines the mechanism by which exosomes (EXO) derived from human amniotic mesenchymal stem cells (hAMSCs) improve ischemic stroke and regulate neural ferroptosis-related injury. MethodsThirty-two SPF-grade male C57BL/6J mice aged 6 - 8 weeks were randomly divided into four groups (n=8 per group): sham group (Sham), model group (MCAO), MCAO plus normal saline group (MCAO+NaCl), and MCAO plus exosome group (MCAO+EXO). The mouse MCAO model was established by electrocoagulation of the middle cerebral artery. Mice in the Sham group underwent exposure of the middle cerebral artery without electrocoagulation. Twenty-four hours before MCAO induction, mice in the MCAO+EXO group received a tail vein injection of 100 μL of exosomes derived from the culture supernatant of hAMSCs at a concentration of 9.5×10¹¹ particles/mL. Mice in the MCAO+NaCl group were injected with an equal volume of normal saline via the tail vein. Twenty-four hours after model establishment, neurological deficits were evaluated using the Longa neurological deficit scoring system. Cerebral infarct volume was assessed by 2,3,5-triphenyltetrazolium chloride (TTC) staining. Hematoxylin and eosin (HE) staining was performed to evaluate morphological changes of neurons in the ischemic brain regions. The contents of ferrous iron (Fe²⁺), malondialdehyde (MDA), total glutathione (total GSH), oxidized glutathione (GSSG), and reduced glutathione (GSH) in the infarct core and peri-infarct regions were determined using microcolorimetric assays to evaluate differences among groups. The mRNA expression levels of ferroptosis-related factors, including nuclear factor erythroid 2-related factor 2 (NRF2), solute carrier family 7 member 11 (SLC7A11), and glutathione peroxidase 4 (GPX4) in the infarct core and peri-infarct regions were measured by real-time quantitative PCR. Protein expression levels of NRF2, SLC7A11, and GPX4 in the infarct and peri-infarct regions of each group were analyzed by Western blotting. ResultsCompared with the MCAO group, the Longa neurological deficit score was significantly reduced in the MCAO+EXO group (P<0.01). Prominent cerebral infarction was observed in the MCAO group, whereas the infarct volume ratio was markedly decreased in the MCAO+EXO group compared with the MCAO group (P<0.001). Histopathological analysis revealed that mice in the MCAO group exhibited obvious neuronal damage, including cytoplasmic vacuolar degeneration, nuclear pyknosis and fragmentation, unclear nuclear structure, and disorganized neuronal arrangement, compared with the Sham group. In contrast, neurons in the MCAO+EXO group showed relatively preserved morphology, with intact cellular structures and large, regular nuclei located centrally within the cells. Biochemical analysis demonstrated that Fe²⁺ and MDA levels in the infarct core and peri-infarct regions were significantly increased in the MCAO group compared with the Sham group (P<0.001). These levels were significantly reduced in the MCAO+EXO group compared with the MCAO group (P<0.01). In addition, total glutathione (total GSH), oxidized glutathione (GSSG), and reduced glutathione (GSH) levels were markedly decreased in the MCAO group relative to the Sham group (P<0.01). Compared with the MCAO group, the MCAO+EXO group exhibited significantly increased levels of total GSH and GSH (P<0.001), while no significant change was observed in GSSG levels (P>0.05). Furthermore, both mRNA and protein expression levels of nuclear factor erythroid 2-related factor 2 (NRF2), solute carrier family 7 member 11 (SLC7A11), and glutathione peroxidase 4 (GPX4) were significantly downregulated in the MCAO group compared with the Sham group (P<0.01, P<0.001). In contrast, both mRNA and protein expression levels of NRF2, SLC7A11, and GPX4 were significantly upregulated in the MCAO+EXO group compared with the MCAO group (P<0.05). ConclusionIn the mouse MCAO model, tail vein injection of exosomes derived from hAMSCs can improve motor function, reduce infarct area, protect neuronal cell morphology, and reduce the degree of nerve injury. Exosomes may exert a protective effect by activating the NRF2/SLC7A11/GPX4 pathway and reducing ferroptosis in neuronal cells of MCAO model mice.

Objective: To investigate the characteristics and risk factors of an outbreak of acute hemorrhagic conjunctivitis (AHC) in a boarding middle school in Guangdong Province, in order to provide a scientific evidence for effective prevention and control of campus AHC outbreaks. Methods: From September 1st to 28th 2023, case identification was conducted among 559 students and 60 faculty members using standardized definition. Descriptive analysis was conducted on the three distrubution patterns of the outbreak. Questionnaires were designed, and a case-control study was adopted to analyze the possible risk factors of the disease transmission. The propensity score matching (PSM) method was used to control the difference of baseline data. Results: A total of 269 cases of AHC were identified, with an attack rate of 43.46%. The pathogen was confirmed as Coxsackie virus A24 variant (CA24v). Among these, 264 cases were students (attack rate of 47.23%) and 5 were staff (attack rate of 8.33%). A total of 153 pairs of PSM were successfully matched. After PSM matching, there were no statistically significant differences in gender, grade and class between the case group and the control group ( χ 2=0.12, 5.41, 11.24, P >0.05). The results of multivariate Logistic regression analysis showed that middle school students whose towels contacted with others ( OR =1.81), and direct contact with other AHC cases recently ( OR =4.89) were more likely to have AHC; while wearing glasses ( OR =0.43) and frequent use of hand sanitizer ( OR = 0.37 ) were less likely to have AHC ( P <0.05). Conclusion The outbreak of AHC is caused by CA24v, demonstrating rapid spread and extensive impact within the school setting.

BACKGROUND:Ferroptosis-mediated ischemia-reperfusion injury plays a crucial role in the occurrence and progression in pressure ulcers,and there may be pressure ulcer-associated ferroptosis biomarkers,but the mechanism has not been elucidated. OBJECTIVE:To investigate the molecular mechanisms underlying pressure ulcers using bioinformatic analysis,with a focus on identifying differentially expressed genes associated with ferroptosis during the process of pressure ulcer formation,thereby providing novel insights into the clinical treatment of pressure ulcers. METHODS:The single-cell transcriptome sequencing dataset and ferroptosis-related genes were obtained and preprocessed from the Gene Expression Omnibus(GEO)and FerrDb databases.We performed clustering and proportion analyses,metabolic activity and pseudotime analysis,cell communication analysis,ferroptosis gene set cell population identification,and enrichment analysis to determine differentially expressed genes related to ferroptosis.Animal experiments were then conducted for further validation,with 20 Sprague-Dawley rats randomly assigned into a control group and a model group(n=10 per group).The control group received no treatment,while the model group underwent a cycle of ischemia-reperfusion to establish pressure ulcer models.Changes in differentially expressed genes and proteins in the wound tissues of pressure ulcer rats were detected using fluorescent quantitative PCR and western blot,respectively. RESULTS AND CONCLUSION:The single-cell transcriptome sequencing data were clustered into six cell types,with a higher proportion of type 2 and type 3 keratinocytes observed in the pressure ulcer group.There was evident metabolic heterogeneity and evolutionary trajectory among cell populations.Type 2 and type 3 keratinocytes exhibited stronger cell communication,while type 2 keratinocytes demonstrating optimal ligand-receptor interactions.Type 2 keratinocytes demonstrated higher scores for ferroptosis,accompanied by significant upregulation or downregulation of specific genes.A total of 27 Gene Ontology enrichments,20 Kyoto Encyclopedia of Genes and Genomes enrichments,and 24 ferroptosis-related differentially expressed genes,including glutathione peroxidase 4(GPX4)and acyl-CoA synthetase long chain family member 4(ACSL4),were identified.Animal experiments further confirmed the downregulation of GPX4,the ferroptosis-inhibiting protein,and the upregulation of ACSL4,the ferroptosis-promoting protein,in the model group.Overall,these findings indicate the presence of ferroptosis in pressure ulcer tissue.GPX4 and ACSL4 are important genes regulating ferroptosis in pressure ulcer tissues.

Background and purpose:In recent years,domestic radiotherapy equipment and related software have made great progress,and testing the functionality and stability of the equipment and software is an essential step.This paper focused on comparing the differences in intensity-modulated radiation therapy(IMRT)plans dosimetry and organ at risk(OAR)volume calculations for common cancers between uRT-treatment planning system(TPS)and Monaco-TPS,and to evaluate the feasibility of dose calculation for Infinity linac(linear accelerator,Elekta,Sweden)using uRT-TPS.Methods:Twenty cases of rectal cancer,lung cancer,breast cancer and nasopharyngeal carcinoma were selected.The IMRT plans were completed in uRT-TPS and Monaco-TPS.The dose uniformity and conformity,mean dose,maximum dose of planning target volume(PTV)and OAR between two plans under the same prescribed dose of PTV were compared.And the pass rates of two TPS plans validated at the same linear accelerator were compared.Meanwhile,monitor units(MU),source skin distance(SSD)and the volume of OAR in uRT-TPS and Monaco-TPS were compared.Results:Wonderful plans that met the clinical requirements were obtained in uRT-TPS and Monaco-TPS.Comparable uniformity and conformability was received in PTV,and the maximum dose of PTV was reduced by 1.1 Gy for uRT-TPS(P = 0.006).For breast cancer and lung cancer,the dose in lung was lower for Monaco-TPS(P＜0.05).For nasopharyngeal carcinoma,the dose indicators that oral cavity and throat in the uRT-TPS was reduced by 9.2%and 5.1%,respectively.The verification results of absolute point dose(＜3%)and three-dimensional surface dose(＞95%)for both plans met the clinical requirements.The region of interest in uRT-TPS was smaller compared with Monaco-TPS(P＜0.05).Conclusion:A comparable IMRT plan was obtained for common tumors in uRT-TPS and Monaco-TPS.It is feasible to calculate the dose of Infinity linac using uRT-TPS.

Objective:To study the crosstalk between the activating transcription factor 6 (ATF6) and inositol-requiring enzyme 1 (IRE1) - X-box binding protein 1 (XBP1) pathway in oxygen-glucose deprivation/reoxygenation (OGD/R)-injured mouse hippocampal neuronal cell line HT22.Methods:The OGD/R-injured HT22 cell model was used to observe the changes of the indicators of endoplasmic reticulum stress (ERS), cell viability, and apoptosis at different OGD/R time points (0, 3, 6, 12, and 24 hours). HT22 cells in the logarithmic growth phase were randomized into blank control group, control+ATF6 activator (AA147) group, control+IRE1 inhibitor (4μ8c) group, OGD/R model group, OGD/R+AA147 group and OGD/R+4μ8c group (10 μmol/L AA147 or 16 μmol/L 4μ8c was given during the whole process in the AA147 group and 4μ8c group). Western blotting was used to detect the expression of ERS-related proteins [glucose-regulated protein 78 (GRP78), phosphorylated-inositol-requiring enzyme 1 (p-IRE1), and phosphorylated-eukaryotic translation initiation factor-2α (p-eIF2α)], and apoptosis-related proteins (Bcl-2, Bax, caspase-3, and cleaved caspase-3). The mRNA of ERS-related genes, and ATF6 [homocysteine-inducible, endoplasmic reticulum stress-inducible, ubiquitin-like domain member 1 (Herpud1), protein disulfide isomerase associated 4 (Pdia4) and Sel-1 suppressor of lin-12-like (Sel1L)] and spliced XBP1 [XBP1s, include DnaJ heat shock protein family member B9 (Erdj4), Sec24 related gene family, member D (Sec24d) and signal sequence receptor, gamma (Ssr3)] induced transcriptional response-related genes were measured by real-time quantitative polymerase chain reaction (RT-qPCR). A cell counting kit-8 (CCK-8) assay was used to detect the viability of HT22 cells. Immunofluorescence was utilized to test the expression of cleaved caspase-3.Results:Compared with the blank control group, the expression of ERS-related proteins p-IRE1 and p-eIF2α were significantly increased at 12 hours and 3 hours following OGD/R, respectively (p-IRE1/β-actin: 2.09±0.10 vs. 1.00±0.00, p-eIF2α/β-actin: 1.39±0.11 vs. 1.00±0.00, both P < 0.01). The mRNA expressions of ERS-related genes [ATF6, XBP1s, unspliced XBP1 (XBP1u), activating transcription factor 4 (ATF4), CCAAT/EBP homologous protein (CHOP)] were also upregulated in different OGD/R timepoint in HT22 cells, which indicated ERS was activated in OGD/R-stimulated HT22 cells. Compared with the OGD/R model group, the expression of protein p-IRE1 was not changed, but the mRNA of XBP1s and XBP1u were obviously downregulated in the OGD/R+AA147 group [XBP1s (2 -ΔΔCt): 0.76 (0.71, 0.92) vs. 1.13 (1.03, 1.29), XBP1u (2 -ΔΔCt): 0.29±0.05 vs. 0.52±0.04, both P < 0.01], whereas the expressions of XBP1s-induced transcriptional response downstream genes did not change significantly. Compared with the OGD/R model group, the protein of short-form ATF6 (sATF6) and GRP78 were not changed after administration of 4μ8c, neither was the mRNA expression of ATF6-induced transcriptional response-related genes. These results showed that the mRNA expression of XBP1s and XBP1u were inhibited by AA147-induced activation of ATF6, but no crosstalk was observed between the transcriptional response induced by ATF6 and XBP1s. Compared with the blank control group, the cell viability decreased significantly at OGD/R 3 hours [(44.64±5.12) % vs. (99.13±5.76) %, P < 0.01], the ratios of apoptosis-related proteins Bax/Bcl-2 and cleaved caspase-3/caspase-3 were significantly increased at OGD/R 3 hours and OGD 0 hour, respectively (Bax/Bcl-2: 6.15±1.65 vs. 1.00±0.00, cleaved caspase-3/caspase-3: 17.48±2.75 vs. 1.00±0.00, both P < 0.01), which indicated that apoptosis was activated in OGD/R-treated HT22 cells. Compared with the OGD/R model group, the cell viability decreased significantly [(36.52±17.78)% vs. (69.90±9.43)%, P < 0.01], and the ratios of Bax/Bcl-2 and cleaved caspase-3/caspase-3 were significantly upregulated in the OGD/R+AA147 group in HT22 cells (Bax/Bcl-2: 2.06±0.31 vs. 1.10±0.25, cleaved caspase-3/caspase-3: 3.35±0.59 vs. 0.55±0.09, both P < 0.01). Conclusion:Under our experimental conditions, no obvious crosstalk between the transcriptional response induced by ATF6 and XBP1s was observed, while ATF6 activation induced by AA147 suppressed mRNA expression of XBP1s and XBP1u and promoted cell death in OGD/R-treated HT22 cells.

Polyetheretherketone (PEEK) as a new type of thermoplastic engineering plastic, has good biological activity, elastic modulus close to human cortical bone and radiation permeability, and has been widely used in medical field. This study aims to explore the safety and clinical efficacy of using 3D printing personalized PEEK materials to repaire scapular bone defects after bone tumor resection. A total of 6 patients who underwent the implantation of 3D printed PEEK scapular prosthesis from January 2020 to December 2021 in Yunnan Cancer Hospital were retrospectively analyzed. There were 3 males and 3 females, with age ranged from 14 to 52 years. There were 1 case of synovial sarcoma, 1 of Ewing's sarcoma, and 4 of chondrosarcoma. PEEK prosthesis was designed and fabricated based on CT data before surgery. Tumor resection and prosthesis replacement were performed under the premise of ensuring safe surgical boundaries, including 2 cases of total scapular prosthesis replacement and 4 cases of partial scapular prosthesis replacement. The operation time was 90-170 min, and the intraoperative blood loss was 100-400 ml. All 6 patients received satisfactory follow-up, with a tumor progression free survival time of 16-28 months. No tumor recurrence or metastasis was observed, and all patients survived tumor free. At last follow-up, the Constant-Murley shoulder joint score was a minimum of 62 points and a maximum of 68 points. The Japanese Orthopaedic Association's shoulder joint score was 63 points minimum and 78 points maximum. Computer-aided design 3D printing PEEK material prosthesis has certain advantages in the treatment of scapular tumor limb salvage. It has light weight, well adapted, relatively simple installation, good histocompatibility, and can obtain a better appearance and function of the shoulder joint after operation. It can become one of the options for limb salvage treatment of scapular tumor.

BACKGROUND: The study aims to correlate osteogenesis with autophagy during the mineralization induction of MC3T3-e1 through exploring the expression of runt-related transcription factor 2 (RUNX2)/lysosomal-associated transmembrane protein 5 (LAMPT5). METHODS: The induction of mineralization in MC3T3-e1 was followed by detecting the expressions of osteogenesisrelated indexes such as RUNX2, alkaline phosphatase (ALP), osteocalcin (OCN), and LAPTM5 using RT-qPCR and Western blot from 0 to 14 days. Transmission electron microscope was utilised in visualizing the alterations of autophagosomes, which was followed by immunofluorescence detecting the subcellular localization of autophagy-related index sequestosome 1 (P62) and microtubule-associated protein 1 light 3 (LC3) protein and scrutinising the expression of P62 mRNA and P62 and LC3 proteins. RESULTS: Induction of MC3T3-e1 mineralization demonstrated an increased expression of osteogenesis-related indicators such as RUNX2, ALP, OCN, and LAPTM5 (p < 0.05), as evident from the results of RT-qPCR and Western blot. Meanwhile, the expression of autophagosomes increased one day after mineralization induction and then experienced a gradual decline, and enhanced expression of LC3 protein was noted on days 1–2 of mineralization induction but was then followed by a corresponding reduce. In contrast, a continuous increase was reported in the expression of P62 mRNA and protein, respectively (p < 0.05). Up- and down-regulating RUNX2/LAPTM5 expression alone confirmed the aforementioned results. CONCLUSION It was therefore proposed that RUNX2 may be responsible for an early increase and then a gradual decrease in LAPTM5-mediated autophagy through the regulation of its high expression. Meanwhile, increased LAPTM5 expression in osteogenic mineralization presumed that RUNX2/LAPTM5 promoted autophagy and osteogenic expression, which may play a bridging role in the regulation of autophagy and osteogenesis.

Objective: To analyze the epidemiological characteristics and influencing factors of COVID-19 confirmed cases with viral nucleic acid re-positive in anal and/or throat swabs after discharge during the domestic imported epidemic stage in Guangdong Province in early 2020. Methods: The COVID-19 confirmed cases with the onset time before March 1, 2020 in Guangdong Province were collected to analyze the demographic data, epidemiological characteristics, and specimen collection and testing data after discharge. Logistic regression model was used for influencing factors analysis of re-positive cases. Results: A total of 1 286 COVID-19 confirmed cases were included, the M(Q₁,Q₃) of age was 44(32,58)years, 617 cases were male, 224 cases were re-positive in anal and/or throat swabs with the re-positive rate 17.42%. The M(Q₁,Q₃) of age of re-positive cases was 35(23, 50) years, which was younger than that of re-negative cases age was those 46(33, 59) years (P<0.001). With the increase of age, re-positive rate decreased (χ²_trend=52.73, P<0.001). 85.27% (191/224) of re-positive cases were found in 14 d after discharge, the duration time of re-positive status was 13(7, 24) d, and 81.69% (183/224) of re-positive cases were re-tested negative in 28 d after re-positive date. No fever and other symptoms had been observed among re-positive cases during the whole follow-up. No secondary infectious cases had been found among close contacts after 14 d of centralized isolation and sampling screening. Univariate logistic regression model analysis revealed that the influencing factors of the re-positive cases included age, occupation, clusters, clinical types, and admission time. Multivariate logistic regression model analysis revealed that age was an independent risk factor. Conclusions: SARS-CoV-2 viral nucleic acid re-positive is found in COVID-19 confirmed cases after discharge in Guangdong Province. Most re-positive cases are confirmed among 14 d after discharge and re-test to negative among 28 d after re-positive date. Age is an risk factor for re-positive cases after discharge.
COVID-19 ; China/epidemiology* ; Epidemics ; Humans ; Male ; Nucleic Acids ; SARS-CoV-2

A retrospective analysis was made on the effectiveness of with laparoscopy model in hepatoma surgery teaching for general practice residency training. One hundred and forty general practice residents undertook rotation in Department of Hepatobiliary Surgery of Fifth Affiliated Hospital of Zhengzhou University from January to December 2020. Seventy residents received multi-disciplinary team (MDT) with laparoscopy mode in hematoma surgery teaching (study group) and another 70 residents received conventional teaching mode (control group). After completing the study, the teaching effectiveness was compared between two groups. The questionnaire survey showed that the satisfaction score in study group was higher than that in control group (21.10±0.31 vs.17.48±0.35, P<0.05). The scores of clinical skill, graduation examination and case analysis in study group were all higher than those in control group(91.80±4.82 vs. 85.20±4.34, 87.5±4.1 vs. 85.1±3.6, 77.25±3.38 vs. 73.65±3.06, all P<0.05). The study indicates that laparoscopic combined with MDT teaching model can significantly improve the effectiveness of hepatoma surgery study for general practice residents, and is worthy of popularization and application in general surgery teaching.

Objective:To investigate the change of microalbuminuria (MA) in patients with RA and its clinical significance.Methods:From January 2018 to December 2019, data of 75 cases of RA patients were collected from outpatient and inpatient wardsof our hospital, and the data of 75 cases of physical examination wascollected as control. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) anti-cyclic citrullinated peptide (CCP) antibody, blood lipid, Homeostasis model assessment for insulin resistance (HOMA-IR), rheumatoid factor (RF), anti-CCP antibodyand MA levels were measured respectively. RA patients were obtained by ultrasound Carotid intima-media thickness (cIMT) and brachial artery flow mediated diastolic function (FMD) were measured. The statistical analysis was carried out with independent t-test, analysis of variance, Pearson correlation analysis and multiple stepwise regression. Results:The MA level of RA patients was significantly higher than that of the healthy control group [(31±5) mg/L vs (25±4) mg/L, t=5.982, P<0.05]. In RA patients, MA level was positively correlated with course of disease ( r=0.327, P=0.015), HOMA-IR ( r=0.576, P<0.01], CRP ( r=0.212, P=0.027), RF ( r=0.585, P<0.01), disease activity score in 28 joints (DAS28) ( r=0.472, P=0.013), cIMT ( r=0.611, P<0.01) and duration of nonsteroidal anti-inflammatory drugs (NSAIDs) use ( r=0.274, P<0.01), and urineMA level( OR=1.763, P<0.01) were independent correlation factors affecting cIMT. Conclusion:The level of MA in RA patients is significantly higher than that in normal controls, and is correlated with disease activity and subclinical atherosclerosis, which could be another important predictor of disease follow-up and early screening of subclinical atherosclerosis in RA patients.