Cadmium/metabolism* ; Kidney ; Cells, Cultured ; Mitochondria ; Metallothionein/metabolism* ; Liver

Objective To evaluate the rabbit modle of frozen shoulder induced by persistent strain injuries and ice com-pression.Methods Twelve clean,healthy male New Zealand rabbits with a mass of(2 500±500)g were selected and randomly divided into a blank group and a control group with 6 rabbits in each group.In the control group,the rabbits were modeled with persistent strain injuries and ice compression,the general conditions of the rabbits and the active and passive activities of the shoulder joint were observed and their body weights were recorded.MRI was performed on the affected shoulder joints at 6 d and 29 d after modelling to observe the fluid and soft tissue;HE staining was used to observe the morphology of the rabbit bi-ceps longus tendon and the synovial membrane of the joint capsule;Masson staining was used to observe the fibrous deposits of the rabbit biceps longus tendon and the synovial membrane of the joint capsule,and the fibrous deposits were analysed semi-quantitatively by Image J software.Results Six days after the end of modeling,the active movement of the shoulder joints in the control group was limited,the passive movement was not significantly limited,and they walked with a limp;29 days after the end of the modeling,the active and passive movements of the shoulder joints in the model group were severely limited.Com-pared with the blank group(2.50±0.14)kg,the body weight of the model group(2.20±0.17)kg was significantly reduced(P＜0.01).MRI showed that 6 days after modelling,the muscles around the shoulder joint were not smooth in shape,the joint cap-sule structure was narrowed and a large amount of fluid was seen in the joint cavity;29 days after modelling,the muscles around the shoulder joint were rough in shape,structure of the joint capsule was unclear and the fluid in the joint cavity was reduced compared with 6 days after modelling.Pathological staining showed that the long-headed biceps tendon fibres in the control group were disorganised,curled or even broken,and the synovial tissue of the joint capsule was heavily vascularised,with col-lagen fibre deposits and severe inflammatory cell infiltration.The fiber deposition of the long head of biceps brachii in the mod-el group[(23.58±3.41)％,(27.56±3.70)％]and synovial tissue[(41.78±5.59)％,(62.19±7.54)％]were significantly higher than those in the blank group[(1.79±1.03)％,(1.29±0.63)％]at 7 and 30 days after modeling and synovial tissue fiber de-position[(8.15±3.61)％,(11.29±7.10)％],as shown by the semi-quantitative analysis of Masson staining results by Image J software.And the longer the time,the more severe the fibrosis(P＜0.01).Conclusion The behavioral,imaging and pathological findings showed that the rabbit frozen shoulder model with persistent strain injuries and ice compression is consistent with the clinical manifestations and pathogenesis of periarthritis,making it an ideal method for periarthritis research.

Isocitrate dehydrogenase 1 (IDH1) R132H is the most common mutated gene in grade II-III gliomas and oligodendrogliomas. Instead of activating telomerase (a reverse transcriptase which using RNA as a template to extend telomere length), the majority of IDH1^R132H mutant glioma maintain telomere length through an alternative mechanism that relies on homologous recombination (HR), which is known as alterative lengthening of telomere (ALT).The phenotype of ALT mechanism include: ALT associated promyelocytic leukemia protein (PML) bodies (APBs); extrachromosomal telomeric DNA repeats such as C- and T-loops; telomeric sister chromatid exchange (T-SCE), etc. The mechanism of ALT activation is not fully understood. Recent studies have shown that mutation IDH1 contributes to ALT phenotype in glioma cells in at least three key ways. Firstly, the IDH1^R132H mutation mediates RAP1 down-regulation leading to telomere dysfunction, thus ensuring persistent endogenous telomeric DNA damage, which is important for ALT activation. Spontaneous DNA damage at telomeres may provide a substrate for mutation break-induced replication (BIR)‑mediated ALT telomere lengthening, and it has been demonstrated that RAP1 inhibits telomeric repeat-containing RNA, transcribed from telomeric DNA repeat sequences (TERRA) transcription to down-regulate ALT telomere DNA replication stress and telomeric DNA damage, thereby inhibiting ALT telomere synthesis. Similarly, in ALT cells, knockdown of telomere-specific RNaseH1 nuclease triggers TERRA accumulation, which leads to increased replication pressure. Overexpression of RNaseH1, on the other hand, attenuates the recombination capacity of ALT telomeres, leading to telomere depletion, suggesting that RAP1 can regulate the level of replication pressure and thus ALT activity by controlling TERRA expression. Secondly, the IDH1^R132H also alters the preference of the telomere damage repair pathway by down-regulating XRCC1, which inhibits the alternative non-homologous end joining (A-NHEJ) pathway at telomeres and alters cellular preference for the HR pathway to promote ALT. Finally, the IDH1^R132H has a decreased affinity for isocitric acid and NADP+ and an increased affinity for α ketoglutarate (α‑KG) and NADPH, so that the mutant IDH1^R132H catalyzes the hydrogenation of α‑KG to produce 2-hydroxyglutarate (2-HG)in a NADPH-dependent manner. Because 2-HG is structurally similar to α‑KG, which maintains the trimethylation level of H3k9me3 by competitively inhibiting the activity of the α‑KG-dependent histone demethylase KDM4B, and recruits heterochromatin protein HP1α to heterochromatinize telomeres, and promote ALT phenotypes in cooperation with the inactivating of ATRX. In addition, it has been shown that APBs contain telomeric chromatin, which is essentially heterochromatin, and HP1α is directly involved in the formation of APBs. Based on these studies, this article reviews the mechanism of IDH1^R132H mediated telomere dysfunction and the preference of DNA repair pathway at telomeres in cooperate with ATRX loss to promote ALT, which may provide references for clinical targeted therapy of IDH1^R132H mutant glioma.

Circular RNAs (circRNAs) are a kind of non-coding RNA (ncRNA) with covalent closed-loop structure. They have attracted more and more attention because of their high stability, evolutionary conservatism, and tissue expression specificity. It has shown that circRNAs are involved in the development of a variety of diseases including malignant tumors recently. Nasopharyngeal carcinoma (NPC) is a malignant tumor that occurs in the nasopharynx and has a unique ethnic and geographical distribution in South China and Southeast Asia. Epstein-Barr virus (EBV) infection is closely related to the development of NPC. Radiotherapy and chemotherapy are the mainstays of treatment for NPC. But tumor recurrence or distant metastasis is the leading cause of death in patients with NPC. Several studies have shown that circRNAs, as gene expression regulators, play an important role in NPC and affect the progression of NPC. This review mainly summarized the research status of abnormally expressed circRNAs in NPC and EBV-encoded circRNAs. We also discussed the possibility of circRNAs as a therapeutic target, diagnostic and prognostic marker for NPC.

Objective To explore the influence factors and predictors of treatment response after adrenocorticotropic hormone(ACTH)in infantile epileptic spasms syndrome(IESS).Methods A retrospective analysis was conducted on 80 cases of IESS infants(50 males and 30 females)who were diagnosed and treated with ACTH in Chengdu Women's and Children's Central Hospital from January 2016 to December 2020.Patients were divided into effective group(n=39)and ineffective group(n=41)based on their response of ACTH treatment after 28 days,and their clinical data including the patients'basic information,etiology,treatment programmer,per-and post-treatment Kramer scores of electroencephalogram(EEG)hypsarrhythmia severity and so on,were collected to compare and analyze between the two groups.A modified Poisson regression model was constructed to discover predictors of outcome,and the receiver operating characteristic(ROC)curves were used to assess the prognosis evaluation of the positive predictive value.Results The ages at seizure onset ranged from one month and seven days to one year and nine months.Seizure types included simple epileptic spasms in 66 cases and combined with other types(focal and secondarily generalized seizures)in 14 cases.Thirty-two cases had been given anti-seizure medications(ASMs)before ACTH treatment.The median Kramer scores per-treatment and at 14 days post-treatment were 10.0(8.3,12.0)and 6.0(4.0,7.0),respectively.After ACTH treatment,39(48.8%)cases were effective.Compared with the effective group,the ineffective group had significantly higher proportion of abnormal perinatal conditions,unknown aetiology with normal development,ASMs given before ACTH treatment,the dosages of ACTH greater than 2 U/(kg·d),combinations of two or more ASMs,poor control,and still seizure attack after ACTH treatment of 14 days(P<0.05).Additionally,the Kramer scores after ACTH treatment of 14 days in the ineffective group were also significantly higher(P<0.05).The modified Poisson regression model showed that there were significant statistic differences between the two groups on ASMs given before ACTH treatment(RR=0.546,95%CI 0.357-0.833,P=0.005)and Kramer scores of hypsarrhythmia severity(RR=0.701,95%CI 0.620-0.792,P<0.001),while there were no significant differences between the two groups in term of ages,gender,perinatal conditions,etiologies,seizure types,Kramer scores before treatment,time lag between onset and treatment,duration of ACTH treatment,kinds of ASMs combination.ROC curve analysis showed that only Kramer scores at 14 days after ACTH treatment could predict the treatment response with sensitivity and specificity of 92.7%and 84.6%,respectively,with Youden index of 0.773.The area under the ROC curve was 0.930(95%CI 0.873-0.987,P<0.001)and the cut-point of the score was 6,indicating that the higher the Kramer scores at 14 days after ACTH treatment,the worse the treatment response.The treatment response rate would reduce by about 30.0%if the Kramer score increased by one point.Conclusion ASMs given before ACTH treatment may influence the treatment response.Kramer scores greater than 6 at day 14 after ACTH treatment may be used as a predictor of treatment response after ACTH in IESS patients.

Objective To observe the effect of neuromuscular electrical stimulation(NMES)on interleukin-6(IL-6)/STAT3 signaling pathway in mice after spinal cord injury,and to explore the mechanism of its effect on motor function recovery.Methods Seventy-two SPF grade mice were randomly divided into sham operation group,spinal cord injury(SCI)group and NMES group.BMS score,inclined plane test and neuromuscular electrophysiology(EMG)were used to evaluate the recovery of spinal cord injury in mice.Western blotting and Real-time PCR were used to detect the expression of inflammatory factors,IL-6/STAT3,glial fibrillary acidic protein(GFAP)and brain-derived neurotrophic factor(BDNF)in spinal cord tissues of three groups of mice.HE staining was used to observe the pathological changes of spinal cord injury.Results BMS scores and the inclined plane test of mice in the NMES group were higher than those in SCI group(P＜0.05).The maximum amplitude of motor evoked potential in NMES group was higher than that in SCI group(P＜0.05).The expressions of TNF-α,IL-12A and GFAP in the spinal cord of NMES group were lower than that of SCI group(P＜0.05),while the expressions of TGF-β,IL-10 and BDNF were higher than that of SCI group(P＜0.05).The protein expressions of IL-6/STAT3 signaling pathway of NMES group were lower than that of SCI group(P＜0.05).Conclusion Neuromuscular electrical stimulation plays an anti-inflammatory role by inhibiting the IL-6/STAT3 signaling pathway,thereby promoting the recovery of hind limb motor function in mice after spinal cord injury.

Objective:To investigate the effects of overexpression of Nkx2.5 gene on the anti apoptotic ability of bone marrow mesenchymal stem cells (BMSCs) and cardiac function after myocardial infarction.Methods:A cell ischemia model was established by culturing cells under oxygen glucose deprivation/reoxygenat (OGD/R) conditions. The experiment was divided into four groups: bone marrow mesenchymal stem cells cultured under normal conditions (BMSC group), BMSC group cultured under glucose and oxygen deprivation (BMSC+OGD/R group), overexpressed empty vector BMSC group cultured under glucose and oxygen deprivation(BMSC NC+OGD/R group), and overexpressed Nkx2.5 BMSC group cultured under glucose and oxygen deprivation (BMSC Nkx2.5+OGD/R group). The apoptosis rate of BMSCs in each group was detected via flow cytometry, and BMSC protein was extracted. The expression of caspase-3 and pro-caspase-3, caspase-8 and pro-caspase-8, caspase-9, and cytochrome C protein and expression of Nkx2.5 in the BMSCs of each group were detected by Western blot to determine the anti-apoptotic pathway in vitro. The model of myocardial infarction in mice was established by ligating the left anterior descending branch of coronary artery. The experiment was divided into five groups: sham surgery group, myocardial infarction untreated group, myocardial infarction tail vein injection of BMSC group, myocardial infarction tail vein injection of BMSC empty body group, myocardial infarction tail vein injection of BMSC overexpression Nkx2.5 group. The changes of cardiac function in mice were evaluated by echocardiography. Normal distribution econometric data were compared between groups using convenient analysis, and pairwise comparisons were conducted using LSD-t test. Results:The apoptosis rate of the BMSC+OGD/R group (12.98±1.24)% was higher than that of the BMSC group (7.82±0.42)%, and the difference was statistically significant ( P<0.001). The apoptosis rate of the BMSC NKx2.5+OGD/R group (11.26±0.22)% was lower than that of the BMSC+OGD/R group (12.98±1.24)% and the BMSC NC+OGD/R group (13.14±0.70)%, with statistically significant differences ( P<0.05). Compared to BMSC group ((0.36±0.08), (1.13±0.04), (0.36±0.06), (1.12±0.13), (1.23±0.08), (0.60±0.05), (0.67±0.14)), BMSC+OGD/R group ((1.05±0.10), (0.62±0.04), (1.07±0.09), (0.57±0.07), (0.55±0.08), (1.25±0.09), (0.71±0.04)) and BMSC NC+OGD/R group ((1.16±0.16), (0.64±0.06), (1.19±0.16), (0.56±0.06), (0.50±0.06), (1.28±0.06), (0.73±0.04)), the expression of Caspase-3 (0.72±0.08) and pro-caspase-3(0.89±0.09), Caspase-8 (0.63±0.08) and pro-caspase-8(0.85±0.12), Caspase-9 (0.87±0.09), cytochrome C (0.91±0.10), and Nkx2.5 (1.54±0.16) in BMSC Nkx2.5+OGD/R group was statistically significant (all P<0.05). In vivo experiments showed that the heart ejection fraction (29.05±7.07)% of mice treated with BMSC Nkx2.5 after myocardial infarction was significantly improved compared to the BMSC group (16.57±2.09)% and BMSC NC group (18.08±3.27)% (all P<0.05). Conclusion:BMSC Nkx2.5 may enhance the anti-apoptosis ability of BMSCs and improve cardiac function after myocardial infarction by inhibiting the death receptor pathway and the mitochondrial signal pathway .

Cases of human infection with H7 subtype avian influenza virus(AIV)combined with five NA subtypes(N2,N3,N4,N7,and N9)have been reported.This study was aimed at establishing a method for simultaneous detection and dif-ferential diagnosis of H7 and five NA subtypes of AIV.Seven pairs of specific primers were designed according to the conserved sequences of the HA gene of H7 subtype AIV,the NA gene of five NA AIV subtypes,and the M gene of all AIV subtypes.A high-throughput GeXP typing method was established for simultaneous detection of the H7 subtype and the five NA subtypes of AIV by using GeXP multiple gene expression and capillary electrophoresis analysis technology.The specificity and sensitivity of the method were determined,and clinical samples were tested.The specificity results indicated that this method was able to simultaneously detect seven target genes in a single tube;each pair of specific primers was able to detect the corresponding AIV subtype,and the universal detection primers were able to detect all subtypes of AIV,with no cross-reaction with other common avian disease pathogens.Sensitivity results demonstrated that this method was able to simultaneously detect seven target genes with a threshold detection limit was 100 copies/μL.The detection results for 150 clinical samples were consistent with those of viral isolation and identification.The high-throughput GeXP method for simultaneous differential diagnosis of the H7 subtype and five subtypes of AIV established in this study has advantages of high specificity,high sensitivity,rapidity,and simplicity,thus providing a new detection method for the effective prevention and control of AIV.

In black tea,theaflavins (TFs) are one important class of substances that determine sensory quality and have significant medicinal activities. In addition to the four kinds of common TFs,there may be many other theaflavin analogues (TFAs) with similar chemical structures in tea,but the study on them is very limited. Based on the characteristic sub-structure,mass spectrometry (MS) and MS/MS information,a method for screening and annotation of TFAs from the complex ultra high performance liquid chromatography-high-resolution mass spectrometry (UPLC-HRMS) data was proposed in this work. By analyzing the oxidation and polymerization process of a few TFs,the theoretical reaction model of TFs were summarized,which was used to calculate the precursor ion values of potential TFAs. Meanwhile,the diagnostic fragmentation ions and neutral loss of TFAs according to the fragmentation pathways obtained from chemical standards or documented in literatures were summarized. As a result,36 kinds of compounds were successfully annotated based on the calculated precursor ion values and the MS fragmentation patterns,among which 6 kinds of compounds were reported for the first time in tea. In vitro synthesis experiments were carried out to verified the annotation results. Based on the results of quantitation of 36 kinds of TFAs,a partial least squares-discriminant analysis model was used to investigate the changes of these components during black tea manufacturing. The results indicated that these novel TFAs could be used to effectively distinguish the black tea samples before and after fermentation.

Objective To study the pharmacokinetics and bioequivalence of two formulations of rasagiline mesylate tablets in healthy subjects under fasting and fed conditions.Methods The two-period,two-sequence,crossover study design was adopted in the fasting study.Thirty-six subjects were enrolled and given either test preparation or reference preparation 1 mg respectively in two periods.After collecting plasma samples,the plasma concentration of rasagiline was determined by liquid chromatography-tandem mass spectrometry(LC-MS/MS)and the bioequivalence was evaluated using the average bioequivalence(ABE)method.The four-period,two-sequence,fully replicate crossover study design was adopted in the fed study.Forty-eight subjects were enrolled and given the test preparation or the reference preparation at a dose of 1 mg twice respectively in four periods.According to the degree of intra-individual variation of Cmax,AUC0-t and AUC0-∞,the equivalence was evaluated using the reference-scaled average bioequivalence and ABE method,respectively.Results In the fasting study,the pharmacokinetic parameters of rasagiline of the test and reference preparation were as follow:Cmax were(9.70±3.14)and(9.62±3.85)ng·mL-1,AUC0-t were(6.03±1.47)and(6.02±1.95)ng·h·mL-1,AUC0-∞ were(6.13±1.51)and(6.12±1.97)ng·h·mL-1.The 90％confidence interval(CI)of the geometric mean ratio(GMR)were 94.11％-118.06％,99.22％-107.74％and 99.16％-107.44％for Cmax,AUC0-t and AUC0-∞,respectively,which were within the acceptance criteria of 80.00％-125.00％.In the fed study,the pharmacokinetic parameters of rasagiline of the test and reference preparation were as follow:Cmax were(3.00±1.92)and(3.52±1.77)ng·mL-1,AUC0_t were(5.02±1.20)and(5.06±1.20)ng·h·mL-1,AUC0-∞ were(5.11±1.23)and(5.14±1.22)ng·h·mL-1.The 90％CI of GMR were 96.99％-101.19％and 97.17％-101.41％for AUC0-t and AUC0-∞,which were within the acceptance criteria of 80.00％-125.00％.The 95％upper confidence bound of Cmax for were less than"0",and the point estimate of GMR were within the acceptance criteria of 80.00％-125.00％.The incidence of adverse events in fasting and fed studies was 22.86％and 22.92％,respectively,and all adverse events were moderate to mild.Conclusion The two rasagiline mesylate tablets were bioequivalent,and both the formulations were well tolerated.