High temperature stress induced oxidative stress, gut inflammation and disordered metabolome and microbiome in tsinling lenok trout

Tsinling lenok trout (Brachymystax lenok tsinlingensis Li) is a species of cold-water salmon that faces serious challenges due to global warming. High temperature stress has been found to damage the gut integrity of cold-water fish, impacting their growth and immunity. However, limited research exists on the causal relationship between gut microbial disturbance and metabolic dysfunction in cold-water fish induced by high temperature stress. To address this gap, we conducted a study to investigate the effects of high temperature stress (24 °C) on the gut tissue structure, antioxidant capacity, gut microorganisms, and metabolome reactions of tsinling lenok trout. Our analysis using 16 S rDNA gene sequencing revealed significant changes in the gut microbial composition and metabolic profile. Specifically, the abundance of Firmicutes and Gemmatimonadetes decreased significantly with increasing temperature, while the abundance of Bacteroidetes increased significantly. Metabolic analysis revealed a significant decrease in the abundance of glutathione, which is synthesized from glutamate and glycine, under high temperature stress. Additionally, there was a notable reduction in the levels of adenosine, inosine, xanthine, guanosine, and deoxyguanosine, which are essential for DNA/RNA synthesis. Conversely, there was a significant increase in the abundance of D-glucose 6 P. Furthermore, high temperature stress adversely affects intestinal structure and barrier function. Our findings provide valuable insights into the mechanism of high temperature stress in cold-water fish and serve as a foundation for future research aimed at mitigating the decline in production performance caused by such stress.

Locoregional radiotherapy improves survival outcomes in de novo metastatic nasopharyngeal carcinoma treated with chemoimmunotherapy

BACKGROUND

We aimed to investigate the efficacy of locoregional radiotherapy (LRRT) in patients with de novo metastatic nasopharyngeal carcinoma (dmNPC) receiving chemotherapy combined with anti-programmed cell death receptor-1 monoclonal antibodies (anti-PD-1 mAbs) as first-line treatment and identify optimal candidates for LRRT.

MATERIALS AND METHODS

We enrolled patients with dmNPC receiving platinum-based palliative chemotherapy and anti-PD-1 mAbs followed or not followed by LRRT from four centers. The endpoints were progression-free survival (PFS), objective response rate (ORR), and overall survival (OS). We used the inverse probability of treatment weighting (IPTW) to balance the baseline characteristics of the LRRT and non-LRRT groups to minimize selection bias before comparative analyses. Multivariate analyses were carried out using the Cox proportional hazards model.

RESULTS

We included 163 patients with dmNPC (median follow-up: 22 months). The median PFS was 20 months, and the ORR was 92.0%; the median OS was not achieved. After IPTW adjustments, patients who received LRRT had a significant survival benefit over those not receiving LRRT (median PFS: 28 versus 15 months, P < 0.001). The Epstein-Barr virus DNA (EBV DNA) level after four to six cycles of anti-PD-1 mAbs [weighted hazard ratio (HR): 2.19, 95% confidence interval (CI) 1.22-3.92, P = 0.008] and LRRT (weighted HR: 0.58, 95% CI 0.34-0.99, P = 0.04) were independent prognostic factors. Patients with undetectable EBV DNA levels after four to six cycles of anti-PD-1 mAbs (early EBV DNA clearance) benefitted from LRRT (HR: 0.41, 95% CI 0.22-0.79, P = 0.008), whereas those with detectable levels did not (HR: 1.30, 95% CI 0.59-2.87, P = 0.51).

CONCLUSIONS

Palliative chemotherapy combined with anti-PD-1 mAbs followed by LRRT was associated with improved PFS in patients with dmNPC, especially for patients with early EBV DNA clearance.

[Analysis of changes in reporting and diagnosis of pulmonary tuberculosis among children in Liangshan Yi Autonomous Prefecture, Sichuan Province from 2019 to 2021]

Objective: To compare the characteristics of children's pulmonary tuberculosis (PTB) cases reported from 2019 to 2021 before and during the implementation of the Action Plan to Stop Tuberculosis. Methods: Based on the reported incidence data and population data of child pulmonary tuberculosis (PTB) notified to the Chinese Center for Disease Control and Prevention (CDC) Tuberculosis Information Management System (TBIMS) from 2019 to 2021, the population information and clinically relevant information in different years were compared. Results: From 2019 to 2021, the reported cases of PTB in children were 363, 664 and 655, respectively. The number of reported cases increased significantly. The median age of the cases in children increased from 10.4 years in 2019 to 11.7 years in 2021 (P=0.005) over a three-year period. The etiological positive rate increased significantly from 11.6% (42/363) in 2019 to 32.2% (211/655) in 2021 (P<0.001). The positive rate of molecular testing increased most significantly, which became the main means of etiological detection and accounted for 16.7% (7/42), 62.0% (57/92) and 75.4% (159/211) of the children with positive etiological results, respectively. The resistance rates of isoniazid and rifampicin were analyzed in children with PTB who underwent drug sensitivity tests. The results showed that the resistance rates of isoniazid and/or rifampicin were 2/9, 3.9% (2/51) and 6.7% (11/163), respectively, with an average of 6.7% (15/223) over three years. The median patients' delay was 27 (12, 49) days in 2019. It was reduced to 19 (10, 37) days in 2020 and 15 (7, 34) days in 2021, both significantly lower than 2019 (P=0.009 and 0.000 2, respectively). Conclusion: From 2019 to 2021, the reported numbers of children with PTB and children with positive etiological results increase significantly in Liangshan Prefecture, while the diagnosis delay of patients significantly reduces.

[Construction and evaluation of an artificial intelligence-based risk prediction model for death in patients with nasopharyngeal cancer]

OBJECTIVE

To screen the risk factors for death in patients with nasopharyngeal carcinoma (NPC) using artificial intelligence (AI) technology and establish a risk prediction model.

METHODS

The clinical data of NPC patients obtained from SEER database (1973-2015). The patients were randomly divided into model building and verification group at a 7∶3 ratio. Based on the data in the model building group, R software was used to identify the risk factors for death in NPC patients using 4 AI algorithms, namely eXtreme Gradient Boosting (XGBoost), Decision Tree (DT), Least absolute shrinkage and selection operator (LASSO) and random forest (RF), and a risk prediction model was constructed based on the risk factor identified. The C-Index, decision curve analysis (DCA), receiver operating characteristic (ROC) curve and calibration curve (CC) were used for internal validation of the model; the data in the validation group and clinical data of 96 NPC patients (collected from First Affiliated Hospital of Bengbu Medical College) were used for internal and external validation of the model.

RESULTS

The clinical data of a total of 2116 NPC patients were included (1484 in model building group and 632 in verification group). Risk factor screening showed that age, race, gender, stage M, stage T, and stage N were all risk factors of death in NPC patients. The risk prediction model for NPC-related death constructed based on these factors had a C-index of 0.76 for internal evaluation, an AUC of 0.74 and a net benefit rate of DCA of 9%-93%. The C-index of the model in internal verification was 0.740 with an AUC of 0.749 and a net benefit rate of DCA of 3%-89%, suggesting a high consistency of the two calibration curves. In external verification, the C-index of this model was 0.943 with a net benefit rate of DCA of 3%-97% and an AUC of 0.851, and the predicted value was consistent with the actual value.

CONCLUSIONS

Gender, age, race and TNM stage are risk factors of death of NPC patients, and the risk prediction model based on these factors can accurately predict the risks of death in NPC patients.

[A nationalsurveyandresults analysisof seizure prophylaxis after aneurismal subarachnoid hemorrhage]

Investigate theclinical practice of seizure prophylaxis after aneurysmal subarachnoid hemorrhage in Chinese neurosurgeons.Aquestionnaire for this theme was designed and was sent to respondents through the internet.From July 2021 to October 2021, atotal of forty-three eligible questionnaires were collected. All responders come from affiliated hospitals of medical schools in China. Each of these hospitals admitted more than one hundred patients with aneurysmal subarachnoid hemorrhage per year. Only 9.3% (4/43) of responders disagree with the prophylactic use of anticonvulsants. 86.04% (37/43) of responders perform seizure prophylaxis in clinical practice. Sodium valproate is the most commonly used regimen; 94.59% (35/37) of responders who perform prophylaxis chose this drug. The medication period differs sharply fromlessthan 3 daystolongerthan 14 daysamong different hospitals. The use of EEG was insufficient in Chinese patients. A low seizure rate was reported according to the feedback from Chinese neurosurgeons.In China, seizure prophylaxis after subarachnoid hemorrhage was not yet standardized. Clinicians' mastery of relevant knowledge is still not enough. Carrying out high-quality clinical research can help justify the use of anticonvulsants, which could also positively impact rational drug use.

[Safety and efficacy of left atrial appendage closure combined with patent foramen ovale closure for atrial fibrillation patients with patent foramen ovale]

Objective: To analyze the safety and efficacy of combined left atrial appendage (LAA) and patent foramen ovale (PFO) closure in adult atrial fibrillation (AF) patients complicating with PFO. Methods: This study is a retrospective and cross-sectional study. Seven patients with AF complicated with PFO diagnosed by transesophageal echocardiography (TEE) in Zhoupu Hospital Affiliated to Shanghai University of Medicine & Health Sciences from June 2017 to October 2020 were selected. Basic data such as age, gender and medical history were collected. The atrial septal defect or PFO occluder and LAA occluder were selected according to the size of PFO, the ostia width and depth of LAA. Four patients underwent left atrial appendage closure(LAAC) and PFO closure at the same time. PFO closure was performed during a one-stop procedure of cryoablation combined with LAAC in 2 patients. One patient underwent PFO closure at 10 weeks after one-stop procedure because of recurrent transient ischemic attack (TIA). All patients continued to take oral anticoagulants. TEE was repeated 8-12 weeks after intervention. In case of device related thrombus(DRT), TEE shall be rechecked 6 months after adjusting anticoagulant and antiplatelet drug treatment. Patients were follow-up at 1, 3, 6, 12, 24 months by telephone call, and the occurrence of cardio-cerebrovascular events was recorded. Results: Among the 7 patients with AF, 2 were male, aged (68.0±9.4) years, and 3 had a history of recurrent cerebral infarction and TIA. Average PFO diameter was (3.5±0.8)mm. Three patients were implanted with Watchman LAA occluder (30, 30, 33 mm) and atrial septal defect occluder (8, 9, 16 mm). 2 patients were implanted with LAmbre LAA occluder (34/38, 18/32 mm) and PFO occluder (PF1825, PF2525). 2 patients were implanted with LACbes LAA occluder (24, 28 mm) and PFO occluder (PF2525, PF1825) respectively. The patients were followed up for 12 (11, 24) months after operation. TEE reexamination showed that the position of LAA occluder and atrial septal defect occluder or PFO occluder was normal in all patients. DRT was detected in 1 patient, and anticoagulant therapy was adjusted in this patient. 6 months later, TEE showed that DRT disappeared. No cardiovascular and cerebrovascular events occurred in all patients with AF during follow-up. Conclusions: In AF patients complicated with PFO, LAAC combined with PFO closure may have good safety and effectiveness.

[Prospective clinical study on the influence of implant crown and bridge prostheses characteristics on peri-implant disease]

Objective: To investigate the influence of different characteristics of implant-supported fixed dental prostheses on the incidence of peri-implant disease. Methods: Prospective cohort was established for patients who received implant-supported fixed dental prostheses at the Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University between June 2014 and September 2015. Several patient-related factors, implant prostheses factors, and oral hygiene maintenance factors were collected. The Log-rank test was used to compare the peri-implant disease rates of various factors, and the Cox proportional hazards model was used to conduct multivariate study on single factor significant factors to analyze the impact on the incidence of peri-implant disease. Results: A total of 214 subjects and 351 implants were included in the cohort, the follow-up period was (11.0±3.5) months. Finally, 43.0% (92/214) of patients and 37.3% (131/351) of implants developed peri-implant diseases. The incidence of peri-implant mucositis and peri-implantitis was 41.1% (88/214) and 4.2% (9/214) at the subject level,and 34.2% (120/351) and 3.1% (11/351) at the implant level. Among the factors associated with the implant prosthesis, single factor Log-rank analysis showed that prostheses retention methods, proximal contact of the prostheses, occlusion situation were statistical significance (P<0.05). Multivariate analysis using Cox proportional hazards model showed that screw retention (hazard ratio=2.38, 95%CI: 1.42-3.99), proximal contact loss of the prostheses (hazard ratio=2.36, 95%CI: 1.31-4.27) were independent risk factors for peri-implant disease (P<0.05). Conclusions: Factors such as prostheses retention mode and proximal contact characteristics have important influence on the health status of the implant.

Evaluation of different late left ventricular remodeling definitions for predicting long-term outcomes in acute myocardial infarction patients undergoing percutaneous coronary intervention

Background

Late left ventricular remodeling (LLVR) after the index acute myocardial infarction (AMI) is a common complication, and is associated with poor outcome. However, the optimal definition of LLVR has been debated because of its different incidence and influence on prognosis. At present, there are limited data regarding the influence of different LLVR definitions on long-term outcomes in AMI patients undergoing percutaneous coronary intervention (PCI).

Purpose

To explore the impact of different definitions of LLVR on long-term mortality, re-hospitalization or an urgent visit for heart failure, and identify which definition was more suitable for predicting long-term outcomes in AMI patients undergoing PCI.

Methods

We prospectively observed 460 consenting first-time AMI patients undergoing PCI from January 2012 to December 2018. LLVR was defined as a ≥20% increase in left ventricular end-diastolic volume (LVEDV), or a &gt;15% increase in left ventricular end-systolic volume (LVESV) from the initial presentation to the 3–12 months follow-up, or left ventricular ejection fraction (LVEF) &lt;50% at follow up. These parameters of the cardiac structure and function were measuring through the thoracic echocardiography. The association of LLVR with long-term prognosis was investigated by Cox regression analysis.

Results

The incidence rate of LLVR was 38.1% (n=171). The occurrence of LLVR according to LVESV, LVEDV and LVEF definition were 26.6% (n=117), 31.9% (n=142) and 11.5% (n=51), respectively. During a median follow-up of 2 years, after adjusting other potential risk factors, multivariable Cox regression analysis revealed LLVR of LVESV definition [hazard ratio (HR): 2.50, 95% confidence interval (CI): 1.19–5.22, P=0.015], LLVR of LVEF definition (HR: 16.46, 95% CI: 6.96–38.92, P&lt;0.001) and LLVR of Mix definition (HR: 5.86, 95% CI: 2.45–14.04, P&lt;0.001) were risk factors for long-term mortality, re-hospitalization or an urgent visit for heart failure. But only LLVR of LVEF definition was a risk predictor for long-term mortality (HR: 6.84, 95% CI: 1.98–23.65, P=0.002).

Conclusions

LLVR defined by LVESV or LVEF may be more suitable for predicting long-term mortality, re-hospitalization or an urgent visit for heart failure in AMI patients undergoing PCI. However, only LLVR defined by LVEF could be used for predicting long-term mortality.

Funding Acknowledgement

Type of funding sources: None. Association Between LLVR and outcomesKaplan-Meier Estimates of the Mortality

[Genomic investigation of human Streptococcus suis infection in Shandong Province]

To investigate Streptococcus suis (S.suis) isolated from patients in Shandong province using genomic epidemiology and pathogenologic analysis. To provide the foundation to establish reasonable and accurate prevention and control measures of human S. suis infection. Molecular typing, whole genome phylogenetic tree, virulence gene typing, antibiotic resistance profile and mobile genetic elements carrying antibiotic resistance genes of isolated S. suis strains were investigated. The pathogenicity of isolated strains was also evaluated by comparing their capacity to induce pro-inflammatory cytokine production in vitro. S. suis infections in Shandong province were predominantly due to serotype 2 and sequence type 1 strains. The major symptoms were meningitis. The studied strains could be divided into five lineages. All strains belong to highly pathogenic type in Shandong province,Strains from lineage 2 possessed higher capacity to stimulate pro-inflammatory cytokine production than other strains did, even though other strains belong to highly pathogenic strains. In addition, multiple antibiotic resistance genes and corresponding mobile genetic elements werewidespread in S. suis strains from Shandong province, except strains from lineage 3. High diversities in genome, evolutionary path and pathogenicity of S. suis strains from Shandong province were revealed. It was necessary to surveillant the S. suis strain in genomic level.

Three Novel Structural Variations at MHC and IL12B Predisposing to Psoriasis

BACKGROUND

Structural variations (SVs, defined as DNA variants ≥50 bp) have been associated with various complex human diseases. However, research to screen the whole genome for SVs predisposing to psoriasis is still lacking.

OBJECTIVES

This study aimed to investigate the association of SVs and psoriasis.

METHODS

We performed a genome-wide screen on SVs using an imputation method on 5 independent cohorts with 45,386 subjects from the Chinese Han population. Fine mapping analysis, genetic interaction analysis and RNA expression analysis were conducted to explore the mechanism of SVs.

RESULTS

We obtained 4,535 SVs in total and identified 2 novel deletions (esv3608550, OR=2.73, P<2.00×10^-308 ; esv3608542, OR=0.47, P=7.40×10^-28 ) at 6q21.33 (MHC), 1 novel Alu element insertion (esv3607339, OR=1.22, P=1.18×10^-35 ) at 5q33.3 (IL12B), and confirmed 1 previously reported deletion (esv3587563, OR=1.30, P=9.52×10^-60 ) at 1q21.2 (LCE) for psoriasis. Fine mapping analysis including SNPs and small Insertions/Deletions (InDels) revealed that esv3608550 and esv3608542 were independently associated with psoriasis, and a novel independent SNP (rs9378188, OR=1.65, P=3.46×10^-38 ) was identified at 6q21.33. By genetic interaction analysis and RNA expression analysis, we speculate that the association of 2 deletions at 6q21.33 with psoriasis might relate to their influence on the expression of HLA-C.

CONCLUSIONS

Our study constructed the most comprehensive SV map for psoriasis thus far and enriched the genetic architecture and pathogenesis of psoriasis as well as highlighted the nonnegligible impact of SVs on complex diseases.

[Molecular epidemiology of drug resistance genes and carbapenem resistance of Pseudomonas aeruginosa in rural well water]

Objective: To analyze molecular epidemiological characteristics of drug resistance genes and carbapenem resistance of Pseudomonas aeruginosa (PA) in rural well water. Methods: According to Citation of Natural Mineral Water Inspection (GB 8538-2016), a total of 112 well water samples were tested in Juye county of Shandong province, and PFGE and drug susceptibility test were conducted for the identified PA strains. After PCR identification of carbapenem resistance genes, S1-PFGE and Southern blotting were used to determine the location of drug resistance genes, and combined experiments were used to determine gene transferability. Results: The detection rate of PA in rural well water samples in Juye county of Shandong province was 54.46% (61/112). The 61 strains could be divided into 56 PFGE types. There were 2 strains with 100.00% consistent band types, and there was no obvious predominant band type. The results of drug susceptibility experiments showed that 93.44% (57/61) were multi-drug resistant strains, and there were 2 strains carrying bla_VIM-2, both of which were located on the plasmid, and both of them were transferred horizontally with the plasmid. Conclusion: PA carrying carbapenem resistance genes was detected in well water of rural communities in Juye country, and there is the possibility of horizontal transmission of such resistance genes.

UV response characteristics of mixed-phase MgZnO thin films with different structure distributions, high Iuv/Idark ratios, and fast speed MgZnO UV detectors with tunneling breakdown mechanisms

High-performance ultraviolet (UV) detectors with both high responses and fast speeds are hard to make on homogeneous crystal semiconductor materials. Here, the UV response characteristics of mixed-phase MgZnO thin films with different internal structure distributions are studied. The mixed-phase MgZnO-based detector with the given crystal composition has a high response at both deep UV light (96 A W-1 at 240 nm) and near UV light (80 A W-1 at 335 nm). Meanwhile, because of the quasi-tunneling breakdown mechanism within the device, the high-response UV detector also shows a fast response speed (tr = 0.11 μs) and recovery speed (td1 = 26 μs) at deep UV light, which is much faster than both low-response mixed-phase MgZnO-based UV detectors with other structure constitutions and reported high-response UV devices on homogenous crystal materials. The Idark of the device is just 4.27 pA under a 5 V bias voltage, so the signal-to-noise ratio of the device reached 23852 at 5.5 uW cm-2 235 nm UV light. The new quasi-tunneling breakdown mechanism is observed in some mixed-phase MgZnO thin films that contain both c-MgZnO and h-MgZnO parts, which introduce a high response, signal-to-noise ratio, and fast speed into mixed-phase MgZnO-based UV detectors at weak deep UV light.

Exposure to traffic-related air pollution and changes in exhaled nitric oxide and DNA methylation in arginase and nitric oxide synthase in children with asthma

BACKGROUND

Traffic-related air pollution (TRAP) has been associated with increased risk of airway inflammation in children with asthma. While epigenetic changes could potentially modulate TRAP-induced inflammatory responses, few studies have assessed the temporal pattern of exposure to TRAP, epigenetic changes and inflammation in children with asthma. Our goal was to test the time-lag patterns of personal exposure to TRAP, airway inflammation (measured as fractional exhaled nitric oxide, FeNO), and DNA methylation in the promoter regions of genes involved in nitric oxide synthesis among children with asthma.

METHODS

We measured personal exposure to black carbon (BC) and FeNO for up to 30 days in a panel of children with asthma. We collected 90 buccal cell samples for DNA methylation analysis from 18 children (5 per child). Methylation in promoter regions of nitric oxide synthase (NOS1, NOS2A, NOS3) and arginase (ARG1, ARG2) was assessed by bisulfite pyrosequencing. Linear-mixed effect models were used to test the associations of BC at different lag periods, percent DNA methylation at each site and FeNO level.

RESULTS

Exposure to BC was positively associated with FeNO, and negatively associated with DNA methylation in NOS3. We found strongest association between FeNO and BC at lag 0-6 h while strongest associations between methylation at positions 1 and 2 in NOS3 and BC were at lag 13-24 h and lag 0-24 h, respectively. The strengths of associations were attenuated at longer lag periods. No significant associations between exposure to TRAP and methylation levels in other NOS and ARG isoforms were observed.

CONCLUSIONS

Exposure to TRAP was associated with higher levels of FeNO and lower levels of DNA methylation in the promoter regions of the NOS3 gene, indicating that DNA methylation of the NOS3 gene could be an important epigenetic mechanism in physiological responses to TRAP in children with asthma.

Postoperative radiotherapy option based on mediastinal lymph node reclassification for patients with pN2 non-small-cell lung cancer

Background

In this research, we used the mediastinal lymph node reclassification proposed by the International Association for the Study of Lung Cancer (iaslc) to screen for patients with pathologic N2 (pN2) non-small-cell lung cancer (nsclc) who might benefit from postoperative radiotherapy (port).

Methods

The study enrolled 440 patients with pN2 nsclc who received complete surgical resection and allocated them to one of three groups: N2a1 (single-station skip mediastinal lymph node metastasis), N2a2 (single-station non-skip mediastinal lymph node metastasis), and N2b (multi-station mediastinal lymph node metastasis). Rates of local recurrence at first recurrence in patients receiving and not receiving port were compared using the chi-square test. Overall (os) and disease-free survival (dfs) were then compared using Kaplan-Meier survival analysis with log-rank test. In addition, the factors potentially influencing os and dfs were analyzed using univariate and multivariate Cox regression.

Results

The rate of local recurrence for the N2a2 and N2b groups was significantly lower in patients receiving port (p = 0.044 and p = 0.043 respectively). The log-rank test revealed that, for the N2a1 group, differences in os and dfs were not statistically significant between the patients who did and did not receive port (p = 0.304 and p = 0.197 respectively). For the N2a2 group, os and dfs were markedly superior in patients who received port compared with those who did not (p = 0.001 and p = 0.014 respectively). For the N2b group, os was evidently better in patients who received port compared with those who did not (p = 0.025), but no statistically significant difference in dfs was observed (p = 0.134). Multivariate regression analysis revealed that, in the N2a1 group, port was significantly associated with poor os [hazard ratio (hr): 2.618; 95% confidence interval (ci): 1.185 to 5.785; p = 0.017]; in the N2a2 group, port was associated with improved os (hr: 0.481; 95% ci: 0.314 to 0.736; p = 0.001) and dfs (hr: 0.685; 95% ci: 0.479 to 0.980; p = 0.039).

Conclusions

For patients with pN2 nsclc who receive complete resection, port might be beneficial only for patients with single-station non-skip metastasis (N2a2). Patients with single-station skip metastasis (N2a1) and multi-station metastasis (N2b) might not currently benefit from port.

Magnetism and magnetocaloric effect in TlCo2-x Ni x S2 (0 [Formula: see text] x [Formula: see text] 0.05)

We have investigated the magnetism and magnetocaloric effect of TlCo_2-x Ni _x S₂ (0 [Formula: see text] x [Formula: see text] 0.05). TlCo₂S₂ and TlCo_1.97Ni_0.03S₂ are ferromagnetically ordered below 153 K and 142 K with saturated moment 0.82 [Formula: see text] [Formula: see text]/Co and 0.80 [Formula: see text] [Formula: see text]/Co, respectively, while TlCo_1.95Ni_0.05S₂ shows ferromagnetic transition at 132 K. The magnetism displays slightly itinerant character, as inferred from the Rhodes-Wohlfarth ratio. An unusual historical dependence of magnetization in TlCo_1.95Ni_0.05S₂ is consistently observed by scanning both the temperature and magnetic field. The isothermal magnetic entropy change ([Formula: see text] S [Formula: see text]) of TlCo₂S₂ and TlCo_1.95Ni_0.05S₂ are calculated by Maxwell relation and a temperature averaged entropy change is adopted to estimate the figure of merit for the compounds.

Oxidative stress mediated mitochondrial damage plays roles in pathogenesis of diabetic nephropathy rat

OBJECTIVE

Diabetic nephropathy (DN) is considered as a complication of diabetes and accounts for about 40%. Reactive oxygen species (ROS) level continues to increase in DN. However, whether specific ROS levels can alleviate renal damage by improving mitochondrial function has not been investigated.

MATERIALS AND METHODS

DN model was established by intraperitoneal injection of streptozotocin (STZ). The rats were divided into normal group, STZ model group, and N-acetylcysteine (NAC) group. Fasting blood glucose was tested to assess the modeling. The renal injury was evaluated by using hematoxylin-eosin (HE) staining and periodate-Schiff staining. Serum creatinine and 24 h urinary protein levels were determined by renal function detection kit. The levels of ROS and malondialdehyde (MDA) were assessed by the kit to evaluate the effects of oxidative stress and NAC in rats. The mitochondrial damage marker Cyto C level was detected by Western blot.

RESULTS

Blood glucose, serum creatinine, and urinary protein levels were significantly increased in model group compared with the normal group (p<0.05). Blood glucose levels, serum creatinine, and urinary protein levels were markedly improved after the ROS and MDA levels reduced by NAC. Meanwhile, glomerular hypertrophy, mesangial matrix accumulation, and severe renal injury were observed in the model group. NAC administration markedly improved glomerular morphology and mesangial matrix aggregation. Cyto C expression in the model group increased significantly compared with normal control group (p<0.05), while NAC effectively inhibited Cyto C levels.

CONCLUSIONS

Oxidative stress-mediated mitochondrial damage is an important part of the pathogenesis of DN. Inhibition of ROS production can be a potential target for DN treatment.