Causal effect of air pollution on the risk of cardiovascular and metabolic diseases and potential mediation by gut microbiota

BACKGROUND

Epidemiological studies have explored the relationship between air pollution and cardiovascular and metabolic diseases (CVMDs). Accumulating evidence has indicated that gut microbiota deeply affects the risk of CVMDs. However, the findings are controversial and the causality remains uncertain. To evaluate whether there is the causal association of four air pollutants with 19 CVMDs and the potential effect of gut microbiota on these relationships.

METHODS

Genetic instruments for particulate matter (PM) with aerodynamic diameter < 2.5 μm (PM2.5), <10 μm (PM10), PM2.5 absorbance, nitrogen oxides (NOx) and 211 gut microbiomes were screened. Univariable Mendelian randomization (UVMR) was used to estimate the causal effect of air pollutants on CVMDs in multiple MR methods. Additionally, to account for the phenotypic correlation among pollutant, the adjusted model was constructed using multivariable Mendelian randomization (MVMR) analysis to strength the reliability of the predicted associations. Finally, gut microbiome was assessed for the mediated effect on the associations of identified pollutants with CVMDs.

RESULTS

Causal relationships between NOx and angina, heart failure and hypercholesterolemia were observed in UVMR. After adjustment for air pollutants in MVMR models, the genetic correlations between PM2.5 and hypertension, type 2 diabetes mellitus (T2DM) and obesity remained significant and robust. In addition, genus-ruminococcaceae-UCG003 mediated 7.8 % of PM2.5-effect on T2DM.

CONCLUSIONS

This study firstly provided the genetic evidence linking air pollution to CVMDs and gut microbiota may mediate the association of PM2.5 with T2DM. Our findings highlight the significance of air quality in CVMDs risks and suggest the potential of modulating intestinal microbiota as novel therapeutic targets between air pollution and CVMDs.

[Clinical analysis of 14 patients aged ≤ 50 years with high-risk multiple myeloma treated with allogeneic hematopoietic stem cell transplantation]

Objective: To evaluate the efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in young patients with high-risk multiple myeloma (HRMM) and analyzed the factors affecting patient prognosis. Methods: In this retrospective study, we analyzed the clinical data of 14 patients with HRMM with cytogenetic abnormalities or high-risk biological factors who underwent allo-HSCT at the Hematopoietic Stem Cell Transplantation Center of the Institute of Hematology & Blood Diseases Hospital between November 2016 and November 2022. Results: There were seven males and seven females included in the study, with a median age of 39.5 (31-50) years at the time of allo-HSCT. The median number of treatment lines before transplantation was 2 (1-6) . Before allo-HSCT, 42.9% (6/14) of the patients did not achieve complete remission, while 35.7% (5/14) of the patients achieved measurable residual disease positivity. After transplantation, all patients were evaluated for their treatment response, and the overall response rate was 100% (14/14) . All 14 patients successfully underwent allo-HSCT, with median engraftment times for neutrophils and platelets of 11 (10-14) days and 13 (9-103) days, respectively. Acute grade Ⅱ-Ⅳ graft-versus-host disease (GVHD) occurred in five patients (35.7%) , and two patients (14.3%) developed moderate-to-severe chronic GVHD. The median follow-up time after allo-HSCT was 18.93 (4.10-72.53) months, with an expected 2-year transplant-related mortality rate of 7.1% (95% CI 0%-21.1%) and an expected 2-year overall survival rate of 92.9% (95% CI 80.3%-100.0%) . Moreover, the expected 1-year and 2-year progression-free survival rates were 92.9% (95% CI 80.3%-100.0%) and 66.0% (95% CI 39.4%-100.0%) , respectively, and the 2-year cumulative incidence of relapse was 28.9% (95% CI 0%-56.7%) . Upfront allo-HSCT following complete remission after induced therapy and the presence of chronic GVHD might be favorable prognostic factors. Conclusion: allo-HSCT is an effective treatment for improving the prognosis of young patients with HRMM.

[Efficacy and safety of allogeneic hematopoietic stem cell transplantation for the treatment of primary myelofibrosis]

Objective: To evaluate the efficacy and safety of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for the treatment of primary myelofibrosis (PMF) patients. Methods: A total of 14 cases of PMF who underwent allo-HSCT from December 2008 to December 2022 were analyzed retrospectively, including 8 males and 6 females with a median age [M(Q1, Q3)]of 36 (24, 42) years. Three-year overall survival (OS), disease free survival (DFS), cumulative incidence of relapse (CIR), transplantation-related mortality (TRM) were analyzed. Meanwhile, the complications were followed up by telephone and outpatient appointments for 49.6 (9.0,93.1) months. Results: All patients received myeloablative conditioning regimens (MAC). All patients had successful engraftment, and the median time of neutrophils and platelet engraftment were 13.5 (11.8, 18.0) days and 19.5 (13.5, 24.5) days, respectively. Ⅱ-Ⅳ acute graft versus host disease (GVHD) occurred in 3 cases, while chronic GVHD in 8 cases. The rate of 3-year OS,DFS,CIR and TRM were (92.9±6.9)%, (76.0±12.2)%, (38.6±2.7)% and (7.1±0.5)% respectively after a median follow-up time of 1 489.0 (270.3,2 794.8) days. Two patients died from treatment-related complications, one of which died 39 days after transplantation due to heart failure caused by severe anemia, the other patient died 6 years after relapse due to pulmonary infection. Conclusion: Allo-HSCT can be used as a safe and effective approach to treat PMF.

Long-term potentiation-based screening identifies neuronal PYGM as a synaptic plasticity regulator participating in Alzheimer's disease

Synaptic dysfunction is an important pathological hallmark and cause of Alzheimer's disease (AD). High-frequency stimulation (HFS)-induced long-term potentiation (LTP) has been widely used to study synaptic plasticity, with impaired LTP found to be associated with AD. However, the exact molecular mechanism underlying synaptic plasticity has yet to be completely elucidated. Whether genes regulating synaptic plasticity are altered in AD and contribute to disease onset also remains unclear. Herein, we induced LTP in the hippocampal CA1 region of wild-type (WT) and AD model mice by administering HFS to the CA3 region and then studied transcriptome changes in the CA1 region. We identified 89 genes that may participate in normal synaptic plasticity by screening HFS-induced differentially expressed genes (DEGs) in mice with normal LTP, and 43 genes that may contribute to synaptic dysfunction in AD by comparing HFS-induced DEGs in mice with normal LTP and AD mice with impaired LTP. We further refined the 43 genes down to 14 by screening for genes with altered expression in pathological-stage AD mice without HFS induction. Among them, we found that the expression of Pygm, which catabolizes glycogen, was also decreased in AD patients. We further demonstrated that down-regulation of PYGM in neurons impaired synaptic plasticity and cognition in WT mice, while its overexpression attenuated synaptic dysfunction and cognitive deficits in AD mice. Moreover, we showed that PYGM directly regulated energy generation in neurons. Our study not only indicates that PYGM-mediated energy production in neurons plays an important role in synaptic function, but also provides a novel LTP-based strategy to systematically identify genes regulating synaptic plasticity under physiological and pathological conditions.

[Efficacy and safety of allogeneic hematopoietic stem cell transplantation in the treatment of 28 patients with hepatitis-related aplastic anemia]

Objective: To evaluate the efficacy and safety of HLA-haploidentical hematopoietic stem cell transplantation (allo-HSCT) for hepatitis-related aplastic anemia (HRAA) patients. Methods: Retrospective analysis was performed on hepatitis-associated aplastic anemia patients who received haplo-HSCT at our center between January 2012 and June 2022. October 30, 2022 was the final date of follow-up. Results: This study included 28 HRAA patients receiving allo-HSCT, including 18 males (64.3% ) and 10 females (35.7% ), with a median age of 25.5 (9-44) years. About 17 cases of severe aplastic anemia (SAA), 10 cases of very severe aplastic anemia (VSAA), and 1 case of transfusion-dependent aplastic anemia (TD-NSAA) were identified. Among 28 patients, 15 patients received haplo-HSCT, and 13 received MSD-HSCT. The 2-year overall survival (OS) rate, the 2-year failure-free survival (FFS) rate, the 2-year transplant-related mortality (TRM) rate, the 100-day grade Ⅱ-Ⅳ acute graft-versus-host disease (aGVHD) cumulative incidence rate, and the 2-year chronic graft-versus-host disease (cGVHD) cumulative incidence rate were 81.4%, 81.4% (95% CI 10.5% -20.6% ), 14.6% (95% CI 5.7% -34.3% ), 25.0% (95% CI 12.8% -45.4% ), and 4.2% (95% CI 0.6% -25.4% ), respectively. After transplantation, all patients had no significant liver function damage. Compared with the MSD-HSCT group, only the incidence of cytomegaloviremia was significantly higher in the haplo-HSCT group [60.0% (95% CI 35.2% -84.8% ) vs 7.7% (95% CI 0-22.2% ), P=0.004]. No statistically significant difference in the Epstein-Barr virus was found in the 2-year OS, 2-year FFS, 2-year TRM, and 100-day grade Ⅱ-Ⅳ aGVHD cumulative incidence rates and 2-year cGVHD cumulative incidence rate. Conclusion: Allo-HSCT is safe and effective for HRAA, and haplo-HSCT can be used as a safe and effective alternative for newly diagnosed HRAA patients who cannot obtain HLA-matched sibling donors.

[Immunogenicity and safety of revaccination of 23-valent pneumococcal polysaccharide vaccine in people aged 60 years and above]

Objective: To evaluate the immunogenicity and safety of revaccination of 23-valent pneumococcal polysaccharide vaccine (PPV23) in elderly people aged ≥60 years. Methods: The elderly aged ≥60 years with 1 dose of PPV23 vaccination were selected as revaccination group and those without history of pneumococcal vaccine immunization were selected as the first vaccination group. One dose of PPV23 was administered to both groups, and the first blood samples were collected before vaccination while the second blood samples were collected on day 28-40 after vaccination. ELISA was used to detect the concentrations of anti-specific serotype Streptococcus pneumoniae podocyte polysaccharide immunoglobulin G, and the safety of the vaccination was evaluated after 30 days. Results: The geometric mean concentration (GMC) of antibody to 23 serotypes before the vaccination (0.73-13.73 μg/ml) was higher in revaccination group than in the first vaccination group (0.39-7.53 μg/ml), the GMC after the vaccination (1.42-31.65 μg/ml) was higher than that before the vaccination (0.73-13.73 μg/ml) in the revaccination group, and the GMC after the vaccination (1.62-43.76 μg/ml) was higher than that before the vaccination (0.39-7.53 μg/ml) in the first vaccination group; the geometric mean growth multiple in revaccination group (2.16-3.60) was lower than that in the first vaccination group (3.86-16.13); The mean 2-fold antibody growth rate was lower in revaccination group (53.68%, 95%CI: 52.30%-55.06%) than in the first vaccination group (93.16%, 95%CI: 92.18%- 94.15%), all differences were significant (P<0.001). After the vaccination, 13 serotypes of GMC were higher in the first vaccination group than in revaccination group (P<0.001), the differences were not significant for 10 serotypes of GMC (P>0.05). The incidence of local adverse reaction was 19.20% and 13.27% in revaccination group and the first vaccination group, respectively (P=0.174). Conclusions: The antibody level in ≥60 years people who received one dose of PPV23 after a 5-year interval was still higher than that in unvaccinated people. The antibody level decreased after 5 years of the first vaccination, and the antibody level could be rapidly increased by one more dose vaccination, but the overall immune response was lower than that of the first vaccination; revaccination with PPV23 has a good safety.

[Effect and safety of 10-day decitabine-containing conditioning regimen for allogeneic hematopoietic stem cell transplantation in 31 patients with acute myeloid leukemia/myelodysplastic syndrome]

Objective: To investigate the early effect and safety of allogeneic hematopoietic stem cell transplantation (allo-HSCT) with a 10-day decitabine-containing conditioning regimen in the treatment of acute myeloid leukemia (AML) /myelodysplastic syndrome (MDS) . Methods: From April 2021 to May 2022, 31 AML/MDS patients who received allo-HSCT with a 10-day decitabine-containing conditioning regimen were analyzed. Results: AML (n=10), MDS-AML (n=6), CMML-AML (n=1), and MDS (n=14) were identified in 31 patients, 16 males, and 15 females, with a median age of 41 (20-55) yr. Neutrophils and platelets were successfully implanted in 31 patients (100%), with a median implantation duration of 12 (9-30) and 14 (9-42) days, respectively. During the preconditioning period, 16 patients (51.6%) developed oral mucositis, with 15 cases of Ⅰ/Ⅱ grade (48.4%) and one case of Ⅲ grade (3.2%). After transplantation, 13 patients (41.9%) developed CMV viremia, six patients (19.4%) developed hemorrhagic cystitis, and four patients (12.9%) developed a local infection. The median time of acute graft versus host disease (aGVHD) following transplantation was 33 (12-111) days. The cumulative incidence of aGVHD and Ⅲ/Ⅳ grade aGVHD was 41.9% (95% CI 26.9%-61.0%) and 22.9% (95% CI 13.5%-47.5%), respectively. There was no severe cGVHD, and mild and moderate chronic GVHD (cGVHD) incidence was 23.5% (95% CI 12.1%-43.6%). As of November 30, 2022, only one of the 31 patients had relapsed, with a 1-yr cumulative relapse rate (CIR) of 3.2% (95% CI 0.5%-20.7%). There was only one relapse patient death and no non-relapse deaths. The 1-yr overall survival (OS) and disease-free survival (DFS) rates were 92.9% (95% CI 80.3%-100%) and 96.8% (95% CI 90.8%-100%), respectively. Conclusions: A 10-day decitabine-containing conditioning regimen for allo-HSCT reduced relapse and was safe and feasible in treating AML/MDS.

[Survival efficacy of MDS/AML patients with TP53 abnormal received allogeneic hematopoietic stem cell transplantation]

Objective: TP53-abnormal MDS/acute myeloid leukemia (AML) patients' allogeneic hematopoietic stem cell transplantation (allo-HSCT) treatment's effectiveness and influencing factors should be studied. Methods: 42 patients with TP53 gene status change MDS/AML who underwent allo-HSCT from 2014.8.1 to 2021.7.31 at the Hematology Hospital of the Chinese Academy of Medical Sciences were the subject of a retrospective analysis. The 42 patients were divided into three groups: the TP53 deletion group (group A) , TP53 mono-alle mutation group (group B) , and TP53 multi-hit group (group C) . The differences in clinical features and prognostic factors after transplantation were analyzed. Results: There were 42 MDS/AML patients, including 21 patients with MDS, and 21 patients with AML. The median follow-up period was 34.0 (7.5-75.0) months and the median patient age at the time of transplantation was 41.5 (18-63) years old. The total OS was 66.3% (95% CI 53.4%-82.4%) in 3 years after transplantation, and EFS was 61.0% (95% CI 47.7%-78.0%) in 3 years. For 3 years after receiving hematopoietic stem cell transplantation, there were no statistically significant differences in 3-year OS and EFS in groups A, B, and C (P≥0.05) . The 3 years OS was 82.5% (95% CI 63.1%-100.0%) in group A, 60.6% (95% CI 43.5%-84.4%) in group B, and 57.1% (95% CI 30.1%-100.0%) in group C. Univariate analysis revealed that the number of co-mutant genes, pre-HSCT treatment, and disease type did not affect prognosis, while age, karyotype, co-mutation, positive blast cell before transplantation, and positive blast cell after transplantation were common prognostic factors for OS and EFS (P<0.1) . MRD levels before transplantation were found to be independent risk factors for OS (P=0.037, HR=33.40, 95% CI 1.24-901.17) in a multivariate analysis. Conclusion: Patients with MDS/AML who have TP53 mutations can benefit from allo-HSCT, but patients with complex karyotypes have a worse prognosis. Meanwhile, the final flow cytometry (FCM) monitoring blast cell test before HSCT has a certain guiding significance for prognostic assessment.

Serum glycolipids mediate the relationship of urinary bisphenols with NAFLD: analysis of a population-based, cross-sectional study

BACKGROUND

Bisphenol A (BPA) and its substitutes bisphenol S (BPS) and bisphenol F (BPF) are endocrine-disrupting chemicals widely used in consumer products, which have been proposed to induce various human diseases. In western countries, one of the most common liver diseases is non-alcoholic fatty liver disease (NAFLD). However, studies on the associations of the three bisphenols with NAFLD in human beings are scarce.

METHODS

We included 960 participants aged ≥ 20 years from the NHANES 2013-16 who had available data on levels of urinary BPA, BPS and BPF. The hepatic steatosis index (HSI) > 36 was used to predict NAFLD. Logistic regression analysis and mediation effect analysis were used to evaluate the associations among bisphenols, glycolipid-related markers and NAFLD.

RESULTS

A total of 540 individuals (56.3%) were diagnosed with NAFLD, who had higher concentrations of BPA and BPS but not BPF than those without NAFLD. An increasing trend in NAFLD risks and HSI levels was observed among BPA and BPS tertiles (p for trend < 0.05). After adjustment for confounders, elevated levels of BPA or BPS but not BPF were significantly associated with NAFLD. The odds ratio for NAFLD was 1.581 (95% confidence intervals [CI]: 1.1-2.274, p = 0.013) comparing the highest with the lowest tertile of BPA and 1.799 (95%CI: 1.2462.597, p = 0.002) for BPS. Mediation effect analysis indicated that serum high-density lipoprotein cholesterol and glucose had a mediating effect on the relationships between bisphenols and NAFLD.

CONCLUSIONS

The present study showed that high exposure levels of BPA and BPS increased NAFLD incidence, which might be mediated through regulating glycolipids metabolism. Further studies on the role of bisphenols in NAFLD are warranted.

[Efficacy of basiliximab in the treatment of 87 cases of steroid-refractory or steroid-dependent acute graft-versus-host disease]

Objective: To evaluate the efficacy and prognosis of basiliximab in the treatment of steroid-refractory or steroid-dependent acute graft-versus-host disease (SR/SD-aGVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) . Methods: Clinical data of 87 patients with SR/SD-aGVHD in the skin, intestine, and liver after allo-HSCT at the Institute of Hematology & Blood Diseases Hospital Transplantation Center from January 2015 to December 2018 were retrospectively analyzed. The administration plan of basiliximab was as follows: 20 mg for adults and children weighing ≥35 kg and 10 mg for children weighing<35 kg. The drug was administered once on the 1st, 4th, and 8th days, respectively, and then once weekly. The efficacy was evaluated on the 7th, 14th, 21st, and 28th days after basiliximab treatment. Results: ①There were 51 males (58.6%) and 36 females (41.4%) , with a median (range) age of 34 (4-63) years. There were 54 cases of classic aGVHD, 33 of late aGVHD, 49 of steroid-refractory aGVHD, and 38 of steroid-dependent aGVHD. ②Thirty-five patients (40.2%) achieved complete remission (CR) , 23 (26.4%) achieved partial remission (PR) , and 29 had no remission (NR) . The total effective rate[overall response rate (ORR) ] was 66.7% (58/87) . ③The ORR of the classic and late aGVHD groups was 77.8% (42/54) and 48.5% (16/33) , respectively. ④The median (range) follow-up time was 154 (4-1813) days, the 6-month overall survival (OS) rate of the 87 patients was 44.8% (95% CI 39.5%-50.1%) and the 1-year OS was 39.4% (95%CI 34.2%-44.3%) . ⑤After treatment with basiliximab, the 6-month OS in the CR (35 cases) , PR (23 cases) , and NR (29 cases) groups was 80.0% (95%CI 73.2%-86.8%) , 39.1% (95%CI 28.9%-49.3%) , and 6.9% (95%CI 2.2%-11.6%) , respectively (χ(2)=34.679, P<0.001) , and the 1-year OS was 74.3% (95%CI 66.9%-81.7%) , 30.4% (95%CI 20.8%-40.0%) , and 3.4% (95%CI 0%-6.8%) , respectively (χ(2)=43.339, P<0.001) . The OS of the classic and late aGVHD groups was 57.4% (95%CI 50.7%-64.1%) and 24.2% (95%CI 16.7%-31.7%) , respectively (χ(2)=9.109, P=0.004) , and the 1-year OS was 51.9% (95%CI 45.1%-58.7%) and 18.2% (95%CI 11.5%-24.9%) , respectively (χ(2)=9.753, P=0.003) . ⑥Univariate and multivariate analyses showed that late aGVHD (OR=3.121, 95%CI 1.770-5.503, P<0.001) , Minnesota score high-risk group before medication (OR=3.591, 95%CI 1.931-6.679, P<0.001) , active infection before medication (OR=1.881, 95%CI 1.029-3.438, P=0.040) , and impairment of important organ function caused by non-GVHD (OR=3.100, 95%CI 1.570-6.121, P=0.001) were independent risk factors affecting the efficacy of basiliximab. Conclusion: Basiliximab has good efficacy and safety for SR/SD-aGVHD, but not in patients with late aGVHD, high-risk group of Minnesota score, and infection or impaired function of important organs.

Association of FMO3 rs1736557 polymorphism with clopidogrel response in Chinese patients with coronary artery disease

PURPOSE

Dual antiplatelet therapy with aspirin and clopidogrel is commonly used for coronary artery disease (CAD) patients undergoing percutaneous coronary intervention to prevent stent thrombosis and ischemic events. However, some patients show high on-treatment platelet reactivity (HTPR) during clopidogrel therapy. Genetic factors such as loss-of-function variants of CYP2C19 are validated to increase the risk of HTPR. Flavin-containing monooxygenase 3 (FMO3) is reported to be associated with potency of platelet responsiveness and thrombosis. This study aimed to explore the association between FMO3 rs1736557 polymorphism and clopidogrel response.

METHODS

Five hundred twenty-two Chinese CAD patients treated with dual antiplatelet therapy were recruited from Xiangya Hospital. After oral administration of 300 mg loading dose (LD) clopidogrel for 12-24 h or 75 mg daily maintenance dose (MD) clopidogrel for at least 5 days, the platelet reaction index (PRI) was determined by vasodilator-stimulated phosphoprotein-phosphorylation assay. FMO3 rs1736557, CYP2C19*2, and CYP2C19*3 polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTS

Mean PRI value was significantly higher in CYP2C19 poor metabolizers (PMs) and intermediate metabolizers (IMs) than the extensive metabolizers (EMs) (p < 0.001). In addition, FMO3 rs1736557 AA homozygotes showed significantly lower PRI as compared with carriers of the major rs1736557 G allele in the entire cohort and in the MD cohort (p = 0.011, p = 0.008, respectively). The risk of HTPR was decreased significantly in carriers of the rs1736557 A allele (AA vs GG: OR = 0.316, 95% CI: 0.137-0.726, p = 0.005; AA vs GA: OR = 0.249, 95% CI: 0.104-0.597, p = 0.001; AA vs GG+GA: OR = 0.294, 95% CI: 0.129-0.669, p = 0.002), and the association was observed mainly in patients carrying the CYP2C19 LOF allele and in those administered with MD.

CONCLUSION

The FMO3 rs1736557 AA genotype was related to an increased the antiplatelet potency of clopidogrel in Chinese CAD patients. Additional studies are required to verify this finding.

A Pathogenic Variant p.Phe177Val in PSEN1 Causes Early-Onset Alzheimer's Disease in a Chinese Family

Familial Alzheimer’s disease (FAD) present as a positive family history of cognitive decline, with early onset and an autosomal dominant inheritance pattern. FAD is mainly caused by the mutations in the genes encoding for amyloid precursor protein (APP), presenilin-1 (PSEN1), and presenilin-2 (PSEN2). In the present study, we identified a variant (c.529T > G, p.Phe177Val) in PSEN1 across three generations in a Chinese family with FAD using whole-exome sequencing. The mean age of onset was 39 years (range: 37 to 40 years) in this family. In cell transfection studies, the mutant PSEN1 protein carrying p.Phe177Val increased both the production of Aβ42 and the ratio of Aβ42 over Aβ40, as compared to wild-type PSEN1. Our results confirm the pathogenicity of PSEN1 p.Phe177Val variant in FAD and broaden the clinical phenotype spectrum of FAD patients with PSEN1 p.Phe177Val variant.

Cortical Damage Associated With Cognitive and Motor Impairment in Hereditary Spastic Paraplegia: Evidence of a Novel SPAST Mutation

To determine the cortical mechanism that underlies the cognitive impairment and motor disability in hereditary spastic paraplegia (HSP), nine HSP patients from a Chinese family were examined using clinical evaluation, cognitive screening, and genetic testing. Controls were matched healthy subjects. White-matter fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD; tract-based spatial statistics), cortical thickness (FreeSurfer), and subcortical gray matter (FIRST) based on T1-weighted MRI and diffusion tensor imaging were analyzed. A novel mutation in the SPAST gene (NM_014946.3, c.1321+2T>C) was detected. Patients had motor disability and low Montreal Cognitive Assessment (MoCA) scores. Patients showed significantly decreased total gray- and white-matter volumes, corpus callosum volume, cortical thickness, and subcortical gray-matter volume as well as significantly lower FA and AD values and significantly higher MD and RD values in the corpus callosum and corticospinal tract. Cortical thickness, subcortical gray-matter volume, and MoCA score were negatively correlated with disease duration. Cortical thickness in the right inferior frontal cortex was negatively correlated with Spastic Paraplegia Rating Scale score. Cortical thickness and right hippocampus volume were positively correlated with the MoCA score and subscores. In conclusion, brain damage is not restricted to the white matter in SPG4-HSP patients, and widespread gray-matter damage may account for the disease progression, cognitive impairment, and disease severity in SPG4-HSP.

[Outcomes of 138 myelodysplastic syndrome patients with HLA-matched sibling donor allogeneic hematopoietic stem cell transplantation]

目的

评价人组织相容性抗原（HLA）匹配同胞供者外周血干细胞移植（MSD-PBSCT）治疗骨髓增生异常综合征（MDS）的疗效。

方法

回顾性总结2005年9月至2017年12月接受MSD-PBSCT治疗的138例MDS患者临床资料，观察患者总生存（OS）率、无病生存（DFS）率、复发（RR）率及非复发死亡率（NRM），分析影响移植预后的危险因素。

结果

①中位随访1 050（4~4 988）d，3年OS率、DFS率分别为（66.6±4.1）%、（63.3±4.1）%，3年累积RR率、NRM分别为（13.9±0.1）%、（22.2±0.1）%。②单因素分析显示，发生Ⅲ~Ⅳ度急性移植物抗宿主病（aGVHD）、造血干细胞移植合并症指数（HCT-CI）≥2分组和修订的国际预后积分系统（IPSS-R）极高危组的OS率均显著降低[（42.9±13.2）%对（72.9±4.2）%，χ²=8.620，P=0.003；（53.3±7.6）%对（72.6±4.7）%，χ²=6.681，P=0.010；（53.8±6.8）%对（76.6±6.2）%、（73.3±7.7）%，χ²=6.337，P=0.042]。MDS伴有原始细胞过多-2（MDS-EB2）和MDS转化急性髓系白血病（MDS-AML）患者，移植前接收化疗或去甲基化治疗不改善OS[（60.4±7.8）%对（59.2±9.6）%，χ²=0.042，P=0.838]。③多因素分析显示，HCT-CI是影响移植后OS和DFS的独立危险因素（P=0.012，HR=2.108，95%CI 1.174~3.785；P=0.008，HR=2.128，95%CI 1.219~3.712）。

结论

HCT-CI评价MDS患者移植后预后优于IPSS-R预后分组；发生Ⅲ~Ⅳ度aGVHD是影响移植后OS的不良预后因素；MDS-EB2和MDS-AML患者可以不化疗直接行MSD-PBSCT。

Analysis on safety assessment of Tephrosia vogelii Hook to Apis cerana cerana

Tephrosia vogelii Hook was excellent insecticidal plant, it was introduced into China and planted over a large area in Guangdong province. The main active components of T. vogelii was rotenone and it widely found in leaves and pods of T. vogelii. This paper study of the safety assessment of T. vogelii flowers to worker bees. In this paper, the content of rotenone in T. vogelii petal, nectar, pollen, pistil, and stamen samples were investigated by HPLC, and tested the toxicity of T. vogelii flowers for Apis cerana cerana during 24 h. The dissipation and dynamic of rotenone in A. c. cerana different biological compartments were investigated under indoor conditions during 24 h. The results showed, The LT₅₀ of T. vogelii flowers to worker bees were collected from the eastern, western, southern, northern and top were 13.95, 24.17, 12.55, 26.48, and 18.84 h, the haemolymph of worker bees have the highest content of rotenone, the least accumulation of rotenone in workers bee's thorax, and the rate of dissipation was slowly during the whole study. In conclusion, the results showed the T. vogelii create security risks to worker bees under some ecosystems.

[Outcomes and prognostic factors of myelodysplastic syndrome patients with allogeneic hematopoietic stem cell transplantation]

目的

评价异基因造血干细胞移植（allo-HSCT）治疗骨髓增生异常综合征（MDS）的疗效，并分析预后相关因素。

方法

回顾性分析2010年1月至2018年3月接受allo-HSCT治疗的165例MDS患者，主要观察患者总体生存（OS）率、无病生存（DFS）率、复发率及非复发死亡率（NRM），并分析影响预后的危险因素。

结果

全部165例患者中，男105例，女60例，3年OS、DFS率分别为72.5%（95%CI 64.9%~80.1%）、67.4%（95%CI 59.2%~75.6%），3年累积复发率为12.1%（95%CI 7.0%~18.6%），NRM为20.4%（95%CI 14.2%~27.6%）。多因素分析显示，allo-HSCT合并症指数（HCT-CI）是影响OS的独立危险因素（P=0.042，HR=2.094，95%CI 1.026~4.274）。对于难治性贫血伴原始细胞增多（RAEB）及转化为急性髓系白血病（sAML）患者，移植前应用化疗或去甲基化治疗对总体OS无影响[（67.0±7.5）%对（57.7±10.9）%，χ²=0.025，P=0.874]。

结论

allo-HSCT是治疗MDS的有效手段，非复发死亡是影响生存的主要原因。移植前化疗或去甲基化治疗或许不能使RAEB和sAML患者获益。

[Decitabine-based conditioning regimen is feasible and effective in the treatment of myelodysplastic syndrome and chronic myelomonocytic leukemia]

目的

探讨含地西他滨预处理方案异基因造血干细胞移植（allo-HSCT）治疗骨髓增生异常综合征（MDS）、MDS转变急性髓系白血病（MDS-AML）及慢性粒-单核细胞白血病（CMML）的疗效及安全性。

方法

回顾性分析2013年3月1日至2015年5月25日接受包含地西他滨预处理allo-HSCT治疗的22例MDS、CMML、MDS-AML患者的临床资料。

结果

①全部22例患者中男14例、女8例，中位年龄42.5（24~56）岁；MDS 14例，CMML、MDS-AML各4例。②15例采用地西他滨（20 mg·m⁻²·d⁻¹× 5 d）+白消安+环磷酰胺+氟达拉滨+阿糖胞苷预处理方案，7例采用地西他滨+白消安+氟达拉滨+阿糖胞苷预处理方案。无关供者移植、单倍型移植预处理加用兔抗人胸腺细胞免疫球蛋白（ATG）2.5 mg·kg⁻¹·d⁻¹×4 d。③22例（100%）患者均获得粒细胞植入，中位植入时间为13（12~18）d；21例（95.5%）患者获得血小板植入，中位植入时间为16（13~81）d。④急性GVHD、Ⅲ/Ⅳ度急性GVHD发生率分别为（41.3±10.6）%、（18.4±9.7）%；慢性GVHD、广泛型慢性GVHD发生率分别为（56.4±11.3）%、（36.4±12.1）%。⑤8例发生巨细胞病毒（CMV）血症；18例发生感染，其中6例发生于骨髓抑制期，12例发生于造血重建后；2年、3年非复发死亡率分别为（13.9±7.4）%、（24.3±9.5）%。⑥随访至2018年3月31日，14例患者存活，2年、3年总生存率分别为（77.3±8.9）%、（67.9±10.0）%；2年、3年无复发生存率分别为（72.7±9.5）%、（63.6±10.3）%。

结论

对于MDS、CMML和MDS-AML患者而言，包含地西他滨预处理allo-HSCT是一种安全可行的治疗方法。

The Associations of PMF1, ICAM1, AGT, TRIM65, FBF1, and ACOX1 Variants With Leukoaraiosis in Chinese Population

Background: Leukoaraiosis (LA) is shown as white matter hyperintensities on T2-weighted magnetic resonance imaging brain scans. Together with candidate gene association studies (CGAS), multiple genome-wide association studies (GWAS) have reported large numbers of single nucleotide polymorphisms (SNPs) to be associated with LA in European populations. To date, no replication studies have been reported in independent Chinese samples.

Methods: Here, we performed a candidate gene association study comprising 220 Chinese subjects with LA and 50 controls. Thirty-nine polymorphisms on 32 risk genes were selected from previous studies, and they were genotyped through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Genetic association analysis was firstly performed in all subjects with LA. Then, the same analysis was conducted in the six random sampling cohorts of 50 LA patients, respectively. Data analyses on the associations of SNPs with LA risk were evaluated through Pearson’s χ² and multivariate logistic regression tests.

Results: We found that eight polymorphisms in six genes (PMF1, ICAM1, TRIM65, AGT, FBF1, and ACOX1) were significantly associated with LA in the genetic association tests. Except for those eight gene variants, 24 other polymorphisms were not found to be significantly associated with LA in general genetic model, dominant model, recessive model, or multiplicative model. Among those eight polymorphisms, rs2984613 in PMF1 showed significant association with LA in the cohort of 220 LA subjects, and such significant association remained in both general genetic model (OR: 0.262, 95% CI: 0.091–0.752, p_adj = 0.030) and recessive model (OR: 0.323, 95% CI: 0.119–0.881, p_adj = 0.038) when controlling for clinical variables. Seven other significant variants (rs5498 in ICAM1, rs699 in AGT, rs2305913 in FBF1, rs1135640 in ACOX1, and rs3760128, rs7214628, and rs7222757 in TRIM65) were identified in those six random sampling tests that were conducted in the adjusted cohorts of 50 LA patients. In addition, except for rs699 which showed detrimental effect and represented a risk variant for LA, seven other polymorphisms seemed to exert protective effects on LA and to reduce the risk of LA. It is necessary to confirm these associations in an independent cohort.

Conclusions: This first replication study on multiple genes in an independent Chinese population did not replicate any risk polymorphisms for LA other than rs 699 in AGT but revealed the significantly negative associations of PMF1, ICAM1, TRIM65, FBF1, and ACOX1 polymorphisms with LA. It not only supported the strong ethnic differences in the genetics of LA but also indicated that those six identified genes may be involved in Chinese white matter lesions. Larger scales of CGAS and GWAS are necessary to confirm and decipher those ethnic-Han specific risk genes for LA in China.

Inhibition of Phosphoglycerate Mutase 5 Reduces Necroptosis in Rat Hearts Following Ischemia/Reperfusion Through Suppression of Dynamin-Related Protein 1

PURPOSE

Necroptosis is an important form of cell death following myocardial ischemia/reperfusion (I/R) and phosphoglycerate mutase 5 (PGAM5) functions as the convergent point for multiple necrosis pathways. This study aims to investigate whether inhibition of PGAM5 could reduce I/R-induced myocardial necroptosis and the underlying mechanisms.

METHODS

The SD rat hearts (or H9c2 cells) were subjected to 1-h ischemia (or 10-h hypoxia) plus 3-h reperfusion (or 4-h reoxygenation) to establish the I/R (or H/R) injury model. The myocardial injury was assessed by the methods of biochemistry, H&E (hematoxylin and eosin), and PI/DAPI (propidium iodide/4',6-diamidino-2-phenylindole) staining, respectively. Drug interventions or gene knockdown was used to verify the role of PGAM5 in I/R (or H/R)-induced myocardial necroptosis and possible mechanisms.

RESULTS

The I/R-treated heart showed the injuries (increase in infarct size and creatine kinase release), upregulation of PGAM5, dynamin-related protein 1 (Drp1), p-Drp1-S616, and necroptosis-relevant proteins (RIPK1/RIPK3, receptor-interacting protein kinase 1/3; MLKL, mixed lineage kinase domain-like); these phenomena were attenuated by inhibition of PGAM5 or RIPK1. In H9c2 cells, H/R treatment elevated the levels of PGAM5, RIPK1, RIPK3, MLKL, Drp1, and p-Drp1-S616 and induced mitochondrial dysfunctions (elevation in mitochondrial membrane potential and ROS level) and cellular necrosis (increase in LDH release and the ratio of PI⁺/DAPI⁺ cells); these effects were blocked by inhibition or knockdown of PGAM5.

CONCLUSIONS

Inhibition of PGAM5 can reduce necroptosis in I/R-treated rat hearts through suppression of Drp1; there is a positive feedback between RIPK1 and PGAM5, and PGAM5 might serve as a novel therapeutic target for prevention of myocardial I/R injury.

[Effects of preexisting donor-specific HLA antibodies for graft failure in un-manipulated haploidentical hematopoietic stem cell transplantation]

目的

探讨单倍体相合造血干细胞移植中HLA供者特异性抗体（DSA）对干细胞植入的影响以及处理方法。

方法

采用免疫磁珠液相芯片技术，对2016年6月至2017年5月拟行单倍体相合造血干细胞移植患者进行HLA抗体及DSA的检测，对已完成移植患者进行DSA与植入失败相关性分析，检测移植前后DSA水平，探索针对DSA的处理方法。

结果

共检测了92例拟行单倍体相合造血干细胞移植患者的HLA抗体，其中16例（17.4%）存在HLA抗体，6例（6.5%）DSA阳性。在常规清髓性预处理单倍体相合移植中，26例DSA阴性患者中有24例成功植入，仅有2例发生植入失败，而采用常规预处理的4例DSA阳性患者中仅有1例成功植入，其余3例发生植入失败，二组患者植入率差异有统计学意义[92.3%（24/26）对25.0%（1/4），χ²=8.433，P=0.004]。多因素分析显示，DSA是影响供者干细胞植入的唯一因素[OR=12.0（95% CI 1.39~103.5），P=0.024]。6例DSA阳性的患者中，4例次在移植时采取了针对DSA的措施，均获得供者干细胞顺利植入，其中3例HLA-Ⅰ类DSA阳性患者（首次移植2例、二次移植1例）在输入供者干细胞之前输入供者血小板，另1例HLA-Ⅰ、HLA-Ⅱ类DSA并存患者在二次移植时更换供者并给予全身放疗、利妥昔单抗及供者血小板输注。

结论

DSA是导致单倍体相合造血干细胞植入失败的关键因素，移植前应进行常规检查，DSA阳性患者应选用DSA阴性供者；无合适供者时，应采取适当措施降低DSA水平以促进干细胞植入。

[Application of low-dose ATG for GVHD prophylaxis in patients undergoing PBSCT aged over forty years old]

目的

探讨在供、受者年龄均≥40岁同胞相合外周血干细胞移植（MSD-PBSCT）移植物抗宿主病（GVHD）预防方案中增加低剂量抗胸腺细胞球蛋白（ATG）的效果。

方法

回顾性分析2013年3月至2017年4月行MSD-PBSCT且供、受者年龄均≥40岁恶性血液病患者的临床资料。43例患者在常规急性GVHD预防方案（环孢素A或他克莫司联合短疗程甲氨蝶呤）中加入ATG 1.5 mg·kg⁻¹·d⁻¹×3 d（ATG组），55例患者应用常规GVHD预防方案（对照组）。

结果

①ATG组中性粒细胞植入中位时间短于对照组[13（11~17）d对14（12~24）d，P=0.001]，血小板植入中位时间差异无统计学意义[14（11~43）d对15（11~42）d，P=0.071）]。②ATG组+100 d内急性GVHD累积发生率低于对照组[25.6%（95%CI 13.7%~39.3%）对49.1%（95%CI 35.2%~61.6%），P=0.018]，Ⅱ~Ⅳ度急性GVHD、慢性GVHD发生率差异无统计学意义[18.6%（95%CI 8.6%~31.5%）对23.6%（95%CI 13.4%~35.6%），P=0.509；49.6%（95%CI 31.6%~65.3%）对56.4%（95%CI 41.4%~69.0%），P=0.221]。③ATG组与对照组移植后1年巨细胞病毒血症累积发生率差异无统计学意义[21.1%（95%CI 10.3%~34.5%）对31.1%（95%CI 18.8%~44.2%），P=0.429]。④ATG组及对照组移植后2年累积复发率[24.0%（95%CI 11.5%~38.9%）对24.0%（95%CI 12.1%~38.2%），P=0.608]、非复发死亡率[10.2%（95%CI 3.1%~22.1%）对21.6%（95%CI 9.4%~37.0%），P=0.411]及无病生存率[65.8%（95%CI 50.3%~81.3%）对54.4%（95%CI 37.7%~71.1%），P=0.955]差异均无统计学意义，但ATG组移植后2年总生存率优于对照组[83.8%（95%CI 71.8%~90.0%）对58.0%（95%CI 42.2%~73.9%），P=0.019]。

结论

对于年龄较大的MSD-PBSCT患者，在常规GVHD预防方案基础上加入低剂量ATG可以显著降低移植后急性GVHD发生率、改善OS率，病毒感染发生率和复发率无明显增加。

[Expression characteristics and prognosis significance of miRNA-181a in acute myeloid leukemia with normal karyotype]

目的

探讨核型正常急性髓系白血病（CN-AML）患者微RNA（miRNA）-181a的表达水平及其与预后的关系。

方法

采用实时荧光定量PCR法检测120例初诊原发CN-AML患者骨髓单个核细胞miRNA-181a的表达水平，PCR后采用直接测序方法检测IDH1、IDH2、NPM1、FLT3-ITD、DNMT3A和CEBPα突变。分析miRNA-181a表达与基因突变、其他临床指标和预后的关系。

结果

miRNA-181a高表达组和低表达组患者中位总生存（OS）时间分别为25.0和15.0个月（P<0.05）；中位无复发生存（RFS）时间分别为21.4和11.2个月（P<0.001）。miRNA-181a高表达组患者HGB水平、完全缓解率、NPM1野生型比例均较低表达组高，差异有统计学意义（P值均<0.05）；用Cox回归模型多因素分析显示，miRNA-181a高表达是影响CN-AML患者预后的独立因素（HR=2.219，95%CI 1.601~2.432，P=0.018）。

结论

miRNA-181a高表达是独立于临床指标和高频基因突变的预后良好的标志物，miRNA-181a表达水平可作为CN-AML预后的重要指标。

[Allogeneic hematopoietic stem cell transplantation for treatment of refractory and relapsed acute myeloid leukemia: outcomes and prognostic factors]

目的

评价异基因造血干细胞移植（allo-HSCT）治疗难治/复发急性髓系白血病（AML）的疗效，并对预后相关因素进行分析。

方法

回顾性分析allo-HSCT治疗99例难治/复发AML患者总体生存（OS）率、无病生存（DFS）率、移植物抗宿主病（GVHD）发生率、移植相关死亡率（TRM）及复发率，并分析影响预后的危险因素。

结果

全部99例患者中男59例，女40例，中位年龄为35（6~58）岁，均接受清髓性预处理。所有患者中性粒细胞均达植入标准，中位植活时间为14（9~25）d。移植后100 d Ⅱ~Ⅳ度急性GVHD累积发生率为27.3%（95% CI 18.9%~36.3%）；2年慢性GVHD累积发生率为33.9%（95%CI 24.6%~43.5%），其中广泛型慢性GVHD累积发生率为9.3%（95%CI 4.5%~16.1%）。移植后3年OS、DFS、TRM率分别为45.0%（95%CI 34.6%~55.4%）、45.0%（95%CI 34.8%~55.2%）、19.7%（95%CI 12.4%~28.3%），复发率为36.6%（95%CI 26.9%~46.4%）。多因素分析显示，影响OS的独立危险因素包括移植前未缓解[P=0.009，HR=2.21（95%CI 1.22~4.04）]、初诊WBC>50×10⁹/L[P=0.024，HR=2.11（95%CI 1.11~4.02）]、供者年龄>35岁[P=0.031，HR=1.96（95%CI 1.06~3.60）]、移植后未发生慢性GVHD[P=0.008，HR=0.38（95%CI 0.18~0.78）]。根据移植前危险因素（移植前未缓解、初诊WBC>50×10⁹/L、供者年龄>35岁）进行危险度分组，具有0、1、2~3个危险因素患者的3年OS率分别为75.0%、46.9%、15.4%（χ²=26.873，P<0.001）。

结论

allo-HSCT是挽救性治疗难治/复发AML的有效手段，复发是影响生存的主要原因。移植前缓解状态、发病时WBC水平、供者年龄及移植后是否发生慢性GVHD是难治/复发AML患者allo-HSCT预后的独立影响因素。

[Improved outcome by optimized conditioning regimens with an increased dose of cyclophosphamide in allogeneic peripheral blood stem cell transplantation for severe aplastic anemia]

Objective: To respectively analyze the impact of conditioning regimens with a dose-decreased cyclophosphamide (Cy) on the outcome in fully matched sibling donor (MSD) peripheral blood stem cell transplantation (PBSCT) for severe aplastic anemia (SAA) . Methods: Two conditioning regimens with different doses of Cy (150 mg/kg or 120 mg/kg) in combination with fludarabine (Flu) and antithymocyte globulin (ATG) for MSD-PBSCT were investigated in 51 patients with acquired SAA. Results: Overall survival and failure-free survival in patients received 150 mg/kg of Cy (Cy150 cohort) or 120 mg/kg (Cy120 cohort) were 93.5% vs 90.0% (χ(2)=0.170, P=0.680) and 90.3% vs 85.0% (χ(2)=0.285, P= 0.594) respectively. However, either acute or chronic graft-versus-host disease risks were higher in Cy120 cohort than in Cy150 cohort (HR=3.89, 95% CI 1.21-12.53, P=0.023; HR=4.48, 95% CI 1.40-14.32, P= 0.011, respectively) . No difference was found for opportunistic infections or graft failure between two cohorts. Conclusion: Cy at a dose of 150 mg/kg, in combination with Flu and ATG, was more effective than that of 120 mg/kg Cy to produce improved clinical outcome in the setting of acquired SAA patients after MSD-PBSCT.

[Prognostic significance of early phase donor chimerism after allogeneic peripheral blood stem cell transplantation]

Objective: To evaluate the prognostic significance of early phase full donor chimerism (FDC) after myeloablative allogeneic peripheral blood stem cell transplantation (allo-PBSCT). Methods: The clinical data of 72 hematological patients received myeloablative allo-PBSCT from Feb. 2016 to Jul. 2017 were analyzed retrospectively. The median age was 36.5 years (range 4-59), 44 were males and 28 females. Of the donors, there were 35 HLA matched sibling donors, 27 haploidentical donors and 10 unrelated donors. Polymerase chain reaction amplification of short tandem repeat sequence (PCR-STR) was used to detect donor cell chimerism (DC) rate of recipient bone marrow at one, two and three months after transplantation. Results: The median follow-up was 462 d (range: 47-805 d), 55 cases were still alive, and 45 cases were disease-free survival (DFS) at the end of follow-up. The 2-year overall survival (OS) and DFS were (68.9±7.7)% and (59.5±6.3)%, respectively. A number of 16 cases underwent relapses, with 2-year cumulative incidence of (24.1±5.3)%. The median time of recurrence was 157(32-374) d. Forty cases (55.6%) developed acute graft-versus-host diseases (aGVHD), with median time of 35.5 (13-90) d. Chronic GVHD (cGVHD) occurred in 23 patients (31.9%), with median time of 169 (94-475) d. Univariate analysis found the following factors were not related to OS, DFS or relapse rate (RR), including age, sex, blood type and sex of donor-recipient, occurrence of aGVHD and cGVHD. The OS and DFS in cases reached FDC and no FDC at two months after transplantation were (85.2±6.9)% vs (66.1±7.7)% (P=0.051) and (76.7±7.7)% vs (48.9±8.1)% (P=0.021), respectively. The RR rate in FDC group was lower than that in no FDC group [(16.6±6.8)% vs (30.4±7.8)%, P=0.187, respectively]. Conclusion: The present study confirmed the important value for predicting the prognosis with whether or not the patients reached FDC at the early phase after allo-PBSCT. The OS and DFS in cases with FDC at two months after transplantation were significantly higher than those of no FDC patients.

Association of N6AMT1 rs2254638 Polymorphism With Clopidogrel Response in Chinese Patients With Coronary Artery Disease

Dual antiplatelet treatment with aspirin and clopidogrel is the standard therapy for patients undergoing percutaneous coronary intervention (PCI). However, a portion of patients suffer from clopidogrel resistance (CR) and consequently with recurrence of cardiovascular events. Genetic factors such as loss-of-function variants of CYP2C19 contribute a lot to CR. Recently, the N-6-adenine-specific DNA methyltransferase 1 (N6AMT1) rs2254638 polymorphism is reported to be associated with clopidogrel response. To validate the association between N6AMT1 rs2254638 polymorphism and clopidogrel response, 435 Chinese CAD patients receiving aspirin and clopidogrel were recruited. N6AMT1 rs2254638 and CYP2C19^*2/^*3 polymorphisms were genotyped. Platelet reaction index (PRI) was measured by VASP-phosphorylation assay after treated with a 300 mg loading dose (LD) clopidogrel or 75 mg daily maintenance dose (MD) clopidogrel for at least 5 days. There was a significant difference in PRI between LD cohort and MD cohort. Carriers of CYP2C19^*2 allele showed significantly increased PRI in the entire cohort and in respective of the MD and LD cohorts (p < 0.001, p = 0.003, p < 0.001, respectively). However, carriers of CYP2C19^*3 allele exhibited significantly higher PRI only in the entire cohort and LD cohort (p = 0.023, p = 0.023 respectively). PRI value was significantly higher in CYP2C19 PM genotyped patients as compared with those carrying the IM genotypes and EM genotype (p < 0.001). Besides, carriers of the rs2254638 C allele showed significantly higher PRI in entire cohort and in the LD cohort (p = 0.023, p = 0.008, respectively). When the patients were grouped into clopidogrel resistance (CR) and non-clopidogrel resistance (non-CR) groups, CYP2C19^*2 was associated with increased risk of CR in the entire cohort, the LD cohort and the MD cohort (p < 0.001, p < 0.001, and p = 0.019, respectively). Carriers of the rs2254638 C allele also showed increased risk of CR in the entire cohort and the LD cohort (p = 0.024, and p = 0.028, respectively). N6AMT1 rs2254638 remained as a strong predictor for CR (TC vs. TT: OR = 1.880, 95% CI = 1.099–3.216,p = 0.021; CC vs. TT: OR = 1.930, 95% CI = 1.056-3.527, p = 0.032; TC + CC vs. TT: OR = 1.846, 95%CI = 1.126–3.026, p = 0.015) after adjustment for confounding factors. Our study confirmed the influence of CYP2C19^*2 and rs2254638 polymorphisms on clopidogrel resistance in Chinese CAD patients. Both CYP2C19^*2 and N6AMT1 rs2254638 polymorphism may serve as independent biomarkers to predict CR.

Correlation between NADPH oxidase-mediated oxidative stress and dysfunction of endothelial progenitor cell in hyperlipidemic patients

BACKGROUND/AIMS

NADPH (nicotinamide adenine dinucleotide phosphate) oxidase (NOX)-mediated oxidative stress plays a key role in promotion of oxidative injury in the cardiovascular system. The aim of this study is to evaluate the status of NOX in endothelial progenitor cells (EPCs) of hyperlipidemic patients and to assess the correlation between NOX activity and the functions EPCs.

METHODS

A total of 30 hyperlipidemic patients were enrolled for this study and 30 age-matched volunteers with normal level of plasma lipids served as controls. After the circulating EPCs were isolated, the EPC functions (migration, adhesion and tube formation) were evaluated and the status of NOX (expression and activity) was examined.

RESULTS

Compared to the controls, hyperlipidemic patients showed an increase in plasma lipids and a reduction in EPC functions including the attenuated abilities in adhesion, migration and tube formation, concomitant with an increase in NOX expression (NOX2 and NOX4), NOX activity, and reactive oxygen species production. The data analysis showed negative correlations between NOX activity and EPC functions.

CONCLUSIONS

There is a positive correlation between the NOX-mediated oxidative stress and the dysfunctions of circulating EPCs in hyperlipidemic patients, and suppression of NOX might offer a novel strategy to improve EPCs functions in hyperlipidemia.

Incidence and risk factors of leukoaraiosis from 4683 hospitalized patients: A cross-sectional study

Leukoaraiosis (LA) refers to white matter hyperintensities or white matter lesions (WMLs) on magnetic resonance imaging (MRI) scans of the brain; this disease is associated with an increased risk of stroke, dementia, and cognitive decline. The aims of the study are to assess the incidence of LA and its associated risk factors in a Chinese population.A hospital-based cross-sectional study was conducted that included 4683 patients who were 40 years or older. Data collected included age, sex, hypertension, diabetes, smoking, drinking, homocysteine (HCY), and low-density lipoprotein cholesterol (LDL-C) levels in the blood in addition to brain MRI information. We examined the relationship of those putative risk factors with LA, LA occurrence, and LA progression through single-factor and multivariate analyses.Of the total subjects, 58.3% (2731/4683 cases) suffered from LA. LA was more frequent amongst elderly females, particularly in those older than 60, compared to men. The incidence of LA increased with age. Age, sex, hypertension, diabetes, smoking, and HCY levels all were risk factors for LA. Amongst those risk factors, both smoking and high HCY levels were associated with the onset process of LA. Moreover, the multivariate logistic analysis revealed that both drinking and abnormal LDL-C levels were positive regulators in the progression process of LA.This study revealed that the incidence of LA is high in hospitalized patients in China; moreover, age, sex, hypertension, diabetes mellitus, smoking, drinking, and abnormal HCY and LDL-C levels were found to be associated with overall LA risk, LA onset, or LA progression. These results provide insight into strategies for the prevention and treatment of LA.

Dysfunction of endothelial progenitor cells in hyperlipidemic rats involves the increase of NADPH oxidase derived reactive oxygen species production

NADPH oxidase (NOX) is a major source of reactive oxygen species (ROS) in the body and it plays a key role in mediation of oxidative injury in the cardiovascular system. The purposes of this study are to evaluate the status of NOX in endothelial progenitor cells (EPCs) of hyperlipidemic rats and to determine whether NOX-derived ROS promotes the dysfunction of EPCs. The rats were fed on a high-fat diet for 8 weeks to establish a hyperlipidemic rat model, which showed the increased plasma lipids and the impaired functions of circulating EPCs (including the reduced abilities in migration and adhesion) accompanied by an increase in NOX activity and ROS production. Next, EPCs were isolated from normal rats and they were treated with oxidized low-density lipoprotein (ox-LDL) (100 μg/mL) for 24 h to induce a dysfunctional model in vitro. In agreement with our findings in vivo, ox-LDL treatment increased the dysfunctions of EPCs concomitant with an increase in NOX activity and ROS production; these phenomena were reversed by the NOX inhibitor. Based on these observations, we conclude that NOX-derived ROS involved in the dysfunctions of circulating EPCs in hyperlipidemic rats and inhibition of NOX might provide a novel strategy to improve EPC functions in hyperlipidemia.

Characterization and parameterization of aerosol cloud condensation nuclei activation under different pollution conditions

To better understand the cloud condensation nuclei (CCN) activation capacity of aerosol particles in different pollution conditions, a long-term field experiment was carried out at a regional GAW (Global Atmosphere Watch) station in the Yangtze River Delta area of China. The homogeneity of aerosol particles was the highest in clean weather, with the highest active fraction of all the weather types. For pollution with the same visibility, the residual aerosol particles in higher relative humidity weather conditions were more externally mixed and heterogeneous, with a lower hygroscopic capacity. The hygroscopic capacity (κ) of organic aerosols can be classified into 0.1 and 0.2 in different weather types. The particles at ~150 nm were easily activated in haze weather conditions. For CCN predictions, the bulk chemical composition method was closer to observations at low supersaturations (≤0.1%), whereas when the supersaturation was ≥0.2%, the size-resolved chemical composition method was more accurate. As for the mixing state of the aerosol particles, in haze, heavy haze, and severe haze weather conditions CCN predictions based on the internal mixing assumption were robust, whereas for other weather conditions, predictions based on the external mixing assumption were more accurate.

[A three years longitudinal follow-up study of pulmonary function changes in patients with chronic obstructive pulmonary disease]

OBJECTIVE

To investigate the characteristics and the risk factors of pulmonary function in patients with chronic obstructive pulmonary disease (COPD) for a 3 year follow-up.

METHODS

Subjects diagnosed as COPD were followed up for 3 years in the Management Center of Chronic Respiratory Disease at XINQIAO Hospital from September 2009 to June 2012.This was a retrospective study. Parameters related to respiratory function mainly first second forced expiratory volume (FEV1), COPD assessment test (CAT), 6 minutes walking distance (6MWD) and acute exacerbation were recorded during follow-up.

RESULTS

Although the majority of patients were treated with drugs such as inhaled corticosteroid combined with long-term bronchial dilatation during the three years, FEV1 decreased progressively. The average annual decline of FEV1 was(31.80±61.99)ml, translating into a mean annual decline of(3.74±6.18)%. However, there were significant differences in changes of FEV1. Approximately, FEV1 in 78.3% (47/60) patients decreased, only 21.7%(13/60) patients kept stable FEV1. There was a correlation between decrease of FEV1, FEV1%predicted and the exacerbation (r=0.298, 0.361, 0.273; P<0.05). Logistic regression showed that the positive bronchodilator reversibility and the initial FEV1 were the independent factors associated with significant changes in FEV1 (respectively, OR=5.54, 95%CI 1.55-19.73; OR=8.28, 95%CI 1.42-48.32).

CONCLUSION

The changes of pulmonary function in patients with COPD are heterogeneous, although most patients are treated in a standard way. Nearly 80% patients still represent deterioration of pulmonary function. Decline of FEV1 is closely related to the initial pulmonary function and bronchodilator reversibility.

Phosphorylation of Nonmuscle Myosin Light Chain Promotes Endothelial Injury in Hyperlipidemic Rats Through a Mechanism Involving Downregulation of Dimethylarginine Dimethylaminohydrolase 2

Suppression of dimethylarginine dimethylaminohydrolase (DDAH) activation is related to endothelial dysfunction in hyperlipidemia, and nonmuscle myosin regulatory light chain (nmMLC₂₀) has been show to exert transcriptional function in regulation of gene expression. This study aims to explore whether the suppression of DDAH activation promotes endothelial injury under the condition of hyperlipidemia and whether nmMLC₂₀ can regulate DDAH expression in a phosphorylation-dependent manner. The rats were fed with high-fat diet for 8 weeks to establish a hyperlipidemic model, which showed an increase in plasma lipids and endothelial injury, accompanied by an elevation in myosin light chain kinase (MLCK) activity, phosphorylated nmMLC₂₀ (p-nmMLC₂₀) level, and asymmetric dimethylarginine (ADMA) content as well as a reduction in DDAH2 expression, DDAH activity, and nitric oxide (NO) content. Next, human umbilical vein endothelial cells (HUVECs) were incubated with oxidized low-density lipoprotein (ox-LDL; 100 μg/mL) for 24 hours to establish a cellular injury model in vitro. Consistent with the finding in vivo, ox-LDL induced HUVECs injury (apoptosis and necrosis) concomitant with an increase in MLCK activity, p-nmMLC₂₀ level (in total or nuclear proteins), and ADMA content as well as a reduction in DDAH2 expression, DDAH activity, and NO content; these phenomena were attenuated by MLCK inhibitor. Either in hyperlipidemic rats or in ox-LDL-treated HUVECs, there was not significant change in DDAH1 expression. Based on these observations, we conclude that the suppression of DDAH2 expression might account for, at least partially, the vascular endothelial dysfunction in hyperlipidemia, and nmMLC₂₀ plays a role in suppression of DDAH2 expression in a phosphorylation-dependent manner.

Involvement of NADPH oxidases and non-muscle myosin light chain in senescence of endothelial progenitor cells in hyperlipidemia

NADPH oxidase (NOX)-derived reactive oxygen species (ROS) is involved in endothelial dysfunction of hyperlipidemia, and non-muscle myosin regulatory light chain (nmMLC20) is reported to have a transcriptional function in regulation of gene expression. The purposes of this study are to determine whether NOX-derived ROS can promote endothelial progenitor cell (EPC) senescence and whether nmMLC20 can regulate NOX expression through a phosphorylation-dependent manner. The rats were subjected to 8 weeks of high-fat diet feeding to establish a hyperlipidemic model, which showed an increase in plasma lipids and the accelerated senescence and reduced number of circulating EPCs, accompanied by an increase in myosin light chain kinase (MLCK) and NOX activities, p-nmMLC20 level, NOX (NOX2, NOX4) expression, and H2O2 content. Next, EPCs isolated from normal rats were incubated with ox-LDL (100 μg/mL) for 24 h to establish a senescent model in vitro. Consistent with our in vivo findings, ox-LDL treatment increased the senescence of EPCs concomitant with an increase in MLCK and NOX activities, p-nmMLC20 level (in total or nuclear proteins), NOX expression, and H2O2 content; these phenomena were reversed by MLCK inhibitor. NOX inhibitor achieved similar results to that of MLCK inhibitor except that there is no effect on MLCK activity and p-nmMLC20 level. Furthermore, knockdown of nmMLC20, NOX2, or NOX4 led to a down-regulation in NOX and a reduction in ox-LDL-induced EPC senescence. These results suggest that NOX-derived ROS promotes the senescence of circulating EPCs in hyperlipidemia and nmMLC20 may play a transcriptional role in the upregulation of NOX through a phosphorylation-dependent manner.

Significant concentration changes of chemical components of PM1 in the Yangtze River Delta area of China and the implications for the formation mechanism of heavy haze-fog pollution

Since the winter season of 2013, a number of persistent haze-fog events have occurred in central-eastern China. Continuous measurements of the chemical and physical properties of PM1 at a regional background station in the Yangtze River Delta area of China from 16 Nov. to 18 Dec., 2013 revealed several haze-fog events, among which a heavy haze-fog event occurred between 6 Dec. and 8 Dec. The mean concentration of PM1 was 212μgm(-3) in the heavy haze-fog period, which was about 10 times higher than on clean days and featured a peak mass concentration that reached 298μgm(-3). Organics were the largest contributor to the dramatic rise of PM1 on heavy haze-fog days (average mass concentration of 86μgm(-3)), followed by nitrate (58μgm(-3)), sulfate (35μgm(-3)), ammonium (29μgm(-3)), and chloride (4.0μgm(-3)). Nitrate exhibited the largest increase (~20 factors), associated with a significant increase in NOx. This was mainly attributable to increased coal combustion emissions, relative to motor vehicle emissions, and was caused by short-distance pollutant transport within surrounding areas. Low-volatility oxidized organic aerosols (OA) (LV-OOA) and biomass-burning OA (BBOA) also increased sharply on heavy haze-fog days, exhibiting an enhanced oxidation capacity of the atmosphere and increased emissions from biomass burning. The strengthening of the oxidation capacity during the heavy pollution episode, along with lower solar radiation, was probably due to increased biomass burning, which were important precursors of O3. The prevailing meteorological conditions, including low wind and high relative humidity, and short distance transported gaseous and particulate matter surrounding of the sampling site, coincided with the increased pollutant concentrations mainly from biomass-burning mentioned above to cause the persistent haze-fog event in the YRD area.

Salviaolate Protects Rat Brain from Ischemia-Reperfusion Injury through Inhibition of NADPH Oxidase

Salviaolate is a group of depside salts isolated from Danshen (a traditional Chinese herbal medicine), with ≥ 85 % of magnesium lithospermate B. This study aims to investigate whether salviaolate is able to protect the rat brain from ischemia/reperfusion injury and the underlying mechanisms. Rats were subjected to 2 h of cerebral ischemia and 24 h of reperfusion to establish an ischemia/reperfusion injury model. The neuroprotective effects of salviaolate at different dosages were evaluated. A dosage (25 mg/kg) was chosen to explore the neuroprotective mechanisms of salviaolate. Neurological function, infarct volume, cellular apoptosis, nicotinamide adenine dinucleotide phosphate-oxidase activity, and H2O2 content were measured. In a nerve cell model of hypoxia/reoxygenation injury, magnesium lithospermate B was applied. Cellular apoptosis, lactate dehydrogenase, nicotinamide adenine dinucleotide phosphate-oxidase activity, and H2O2 content were examined. Ischemia/reperfusion treatment significantly increased the neurological deficit score, infarct volume, and cellular apoptosis accompanied by the elevated nicotinamide adenine dinucleotide phosphate-oxidase activity and H2O2 content in the rat brains. Administration of salviaolate reduced ischemia/reperfusion-induced cerebral injury in a dose-dependent manner concomitant with a decrease in nicotinamide adenine dinucleotide phosphate-oxidase activity and H2O2 production. Magnesium lithospermate B (20 mg/kg) and edaravone (6 mg/kg, the positive control) achieved the same beneficial effects as salviaolate did. In the cell experiments, the injury (indicated by apoptosis ratio and lactate dehydrogenase release), nicotinamide adenine dinucleotide phosphate-oxidase activity and H2O2 content were dramatically increased following hypoxia/reoxygenation, which were attenuated in the presence of magnesium lithospermate B (10(-5) M), VAS2870 (nicotinamide adenine dinucleotide phosphate-oxidase inhibitor), or edaravone (10(-5) M). The results suggest that salviaolate is able to protect the brain from ischemia/reperfusion oxidative injury, which is related to the inhibition of nicotinamide adenine dinucleotide phosphate-oxidase and a reduction of reactive oxygen species production.

Mitochondrial aldehyde dehydrogenase, a potential drug target for protection of heart and brain from ischemia/reperfusion injury

Mitochondrial aldehyde dehydrogenase (ALDH2) is an isoenzyme of aldehyde dehydrogenases (ALDH), a group of enzymes that are responsible for clearance of aldehydes in the body. In animal myocardial or cerebral ischemia/ reperfusion (I/R) models, accumulation of toxic aldehydes, such as 4-hydroxy-2-nonenal and malondialdehyde, is thought to be an important mechanism for myocardial and cerebral I/R injury. Among the isoenzymes of ALDH, ALDH2 is believed to play a major role in clearance of toxic aldehydes. Thus, ALDH2 might be a potential drug target for protection of the heart or brain from I/R injury. Indeed, some of the newly identified ALDH2 activators (such as Alda-1) have demonstrated beneficial effects on heart and brain I/R injury. In addition, ALDH activity is present at high levels in some stem or progenitor cells, known as ALDH bright (ALDH(br)) cells, which possess potential value in treating patients with myocardial ischemia. The main purpose of this review is 1) to summarize recent findings regarding the role of ALDH2 in protection of heart or brain from I/R injury, 2) to list the available ALDH2 activators with their potency, selectivity and clinical potentials, and 3) to provide a rationale for ALDH(br) cells in clinical therapeutic value.

A novel function of nuclear nonmuscle myosin regulatory light chain in promotion of xanthine oxidase transcription after myocardial ischemia/reperfusion

Nuclear myosin regulates gene transcription and this novel function might be modulated through phosphorylation of the myosin regulatory light chain (p-MLC20). Nonmuscle MLC20 (nmMLC20) is also present in the nuclei of cardiomyocytes and a potential nmMLC20 binding sequence has been identified in the promoter of the xanthine oxidase (XO) gene. Thus, we investigated its function in the regulation of XO transcription after myocardial ischemia/reperfusion (IR). In a rat model of myocardial IR and a cardiomyocyte model of hypoxia/reoxygenation (HR) injury, the cardiac or cell injury, myosin light chain kinase (MLCK) content, XO expression and activity, XO-derived products, and level of nuclear p-nmMLC20 were detected. Coimmunoprecipitation (co-IP), chromatin immunoprecipitation, DNA pull-down, and luciferase reporter gene assays were used to decipher the molecular mechanisms through which nmMLC20 promotes XO expression. IR or HR treatment dramatically elevated nuclear p-nmMLC20 level, accompanied by increased XO expression, activity, and products (H2O2 and uric acid), as well as the IR or HR injury; these effects were ameliorated by inhibition of MLCK or knockdown of nmMLC20. Our findings from these experiments demonstrated that nuclear p-nmMLC20 binds to the consensus sequence GTCGCC in the XO gene promoter, interacts with RNA polymerase II and transcription factor IIB to form a transcription preinitiation complex, and hence activates XO gene transcription. These results suggest that nuclear p-nmMLC20 plays an important role in IR/HR injury by transcriptionally upregulating XO gene expression to increase oxidative stress in myocardium. Our findings demonstrate nuclear nmMLC20 as a potential new therapeutic target to combat cardiac IR injury.

Nuclear cardiac myosin light chain 2 modulates NADPH oxidase 2 expression in myocardium: a novel function beyond muscle contraction

Recent studies demonstrated that NADPH oxidase 2 (NOX2) expression in myocardium after ischemia-reperfusion (IR) is significantly upregulated. However, the underlying mechanisms remain unknown. This study aims to determine if nuclear cardiac myosin light chain 2 (MYL2), a well-known regulatory subunit of myosin, functions as a transcription factor to promote NOX2 expression following myocardial IR in a phosphorylation-dependent manner. We examined the phosphorylation status of nuclear MYL2 (p-MYL2) in a rat model of myocardial IR (left main coronary artery subjected to 1 h ligation and 3 h reperfusion) injury, which showed IR injury and upregulated NOX2 expression as expected, accompanied by elevated H₂O₂ and nuclear p-MYL2 levels; these effects were attenuated by inhibition of myosin light chain kinase (MLCK). Next, we explored the functional relationship of nuclear p-MYL2 with NOX2 expression in H9c2 cell model of hypoxia-reoxygenation (HR) injury. In agreement with our in vivo findings, HR treatment increased apoptosis, NOX2 expression, nuclear p-MYL2 and H₂O₂ levels, and the increases were ameliorated by inhibition of MLCK or knockdown of MYL2. Finally, molecular biology techniques including co-immunoprecipitation (Co-IP), chromatin immunoprecipitation (ChIP), DNA pull-down and luciferase reporter gene assay were utilized to decipher the molecular mechanisms. We found that nuclear p-MYL2 binds to the consensus sequence AGCTCC in NOX2 gene promoter, interacts with RNA polymerase II and transcription factor IIB to form a transcription preinitiation complex, and thus activates NOX2 gene transcription. Our results demonstrate that nuclear MYL2 plays an important role in IR injury by transcriptionally upregulating NOX2 expression to enhance oxidative stress in a phosphorylation-dependent manner.

Inhibition of myosin light chain kinase reduces NADPH oxidase-mediated oxidative injury in rat brain following cerebral ischemia/reperfusion

Previous studies have demonstrated that nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX)-mediated oxidative stress plays a key role in brain injury following cerebral ischemia/reperfusion (I/R) and myosin regulatory light chain kinase (MLCK) has been reported to be involved in NOX activation in lung endothelium. This study was performed to explore the correlation between MLCK and NOX following cerebral I/R and the underlying mechanisms. Sprague-Dawley (SD) rats were subjected to 2 h middle cerebral artery occlusion and 24 h reperfusion to establish a model of focal cerebral I/R injury. At the end of experiments, neurological function, infarct volume, cellular apoptosis, activities of MLCK and NOX, messenger RNA (mRNA) and protein expression of NOX (NOX1-NOX4), phosphorylation level of myosin regulatory light chain (MLC20) and hydrogen peroxide (H2O2) level were determined. The results showed that I/R treatment led to increase in neurological deficit score, infarct volume and cellular apoptosis, accompanied by the elevated activities of MLCK and NOX, expressions of NOX2 and NOX4, levels of phosphorylation MLC20 and H2O2, these effects were attenuated by MLCK specific inhibitor (ML-7). NOX inhibitors (diphenylene iodonium (DPI) or apocynin) were able to achieve similar results to that of ML-7 except no effect on MLCK activity and MLC20 phosphorylation. These results suggest that activation of MLCK contributes to cerebral I/R oxidative injury through upregulation of NOX2 and NOX4 expression, which is involved in phosphorylation of MLC20.

The CELSR1 polymorphisms rs6007897 and rs4044210 are associated with ischaemic stroke in Chinese Han population

BACKGROUND

Recently, CELSR1 was identified by genome-wide association studies (GWAS) as a susceptibility gene for ischaemic stroke (IS) in Japanese individuals.

AIM

The goal was to examine whether CELSR1 variants are associated with IS in the Chinese Han population.

SUBJECTS AND METHODS

This study genotyped two single nucleotide polymorphisms (SNPs) of CELSR1, rs6007897 and rs4044210, in a Chinese sample of 569 IS cases and 581 controls and assessed their genotype and allele associations with IS.

RESULTS

The results showed that rs6007897 and rs4044210 variants of CELSR1 were significantly (p < 0.01) associated with IS. These associations remained after adjustment for age, gender, smoking status, hypertension, diabetes mellitus and hypercholesterolemia. In addition, a significant association was observed of rs6007897 and rs4044210 of CELSR1 with large artery atherosclerosis (LAA), a sub-type of IS (p < 0.01).

CONCLUSION

Taken together, the present study has proven for the first time that CELSR1 is a susceptibility gene for IS in the Chinese Han population, especially for LAA.

Abrupt transition from ferromagnetic to antiferromagnetic of interfacial exchange in perpendicularly magnetized L1(0)-MnGa/FeCo tuned by Fermi level position

An abrupt transition of the interfacial exchange coupling from ferromagnetic to antiferromagnetic was observed in the interface of perpendicularly magnetized L10-MnGa/Fe1-xCox epitaxial bilayers when x was around 25%. By considering the special band structure of the MnGa alloy, we present a model explaining this transition by the spin-polarization reversal of Fe1-xCox alloys due to the rise of the Fermi level as the Co content increases. The effect of interfacial exchange coupling on the coercive force (Hc) and the spin-dependent tunneling effect in perpendicular magnetic tunnel junctions (pMTJs) based on the coupled composite were also studied. Changes from the normal spin valve to inverted magnetoresistance loops corresponding to the coupling transition were observed in pMTJs with MnGa/Fe1-xCox as an electrode.

Alda-1 reduces cerebral ischemia/reperfusion injury in rat through clearance of reactive aldehydes

Many studies demonstrate that accumulation of reactive aldehydes plays an important role in cellular oxidative injury and aldehyde dehydrogenase 2 (ALDH2)-mediated detoxification of reactive aldehydes is thought as an endogenous protective mechanism against cell injury. This study was performed to explore whether Alda-1, a newly identified ALDH2 activator, was able to protect brain against ischemia/reperfusion injury through clearance of reactive aldehydes. In a rat model of focal cerebral ischemia/reperfusion injury, neurological function, infarct volume, cellular apoptosis, mortality, ALDH2 activity and protein expression, contents of 4-hydroxy-2-nonenal (4-HNE), and malondialdehyde (MDA) were determined. The results showed that ischemia/reperfusion treatment led to increase in neurological deficit score, infarct volume, cellular apoptosis, and mortality accompanied by the elevated levels of reactive aldehydes (4-HNE and MDA). There was no significant change in ALDH2 activity and protein expression. Alda-1 treatment at both dosages (15 mg/kg × 2 or 50 mg/kg × 2, i.g.) was able to increase the activity of ALDH2 and decrease the accumulation of reactive aldehydes concomitantly with the improvement of brain injury (decrease in infarct volume, cellular apoptosis, and mortality) and neurological function (decrease in neurological deficit score). However, Alda-1 treatment did not affect ALDH2 protein expression. Our results suggest that the protective effect of Alda-1 on cerebral ischemia/reperfusion injury is related to ALDH2 activation and clearance of reactive aldehydes.