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1.
Exp Cell Res ; : 112090, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32416090

RESUMO

The relationship between Lamin B2 and tumor proliferation and migration is unclear. We explored the impact of Lamin B2 on non-small cell lung cancer (NSCLC) cells. Tissue microarray and immunohistochemistry were combined to evaluate Lamin B2 expression and its relationship with the clinicopathological factors found in NSCLC. Western blotting, immunofluorescence analysis, and bioinformatics were used to investigate the effects of Lamin B2 on various regulatory pathways in cancer. Cytological experiments were conducted to evaluate Lamin B2 expression in tumor cells. We conducted co-immunoprecipitation and chromatin immunoprecipitation to explore the molecular mechanisms underlying the relationship between Lamin B2 and NSCLC and evaluate the results of rescue experiments. Lamin B2 was highly expressed in NSCLC and positively correlated with lymph node metastasis. In NSCLC, Lamin B2 interacted with Cyclin D1, upregulating G9α expression, thus increasing H3K9me2 levels. H3K9me2 binds to the promoter region of the E-cadherin gene (CDH1) to induce CDH1 silencing and promotes cancer cell migration. Thus, we found that Lamin B2 was highly expressed in NSCLC cells and promoted their migration by increasing H3K9me2 levels, which induced E-cadherin gene silencing.

2.
J Int Med Res ; 48(5): 300060520920438, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32363972

RESUMO

BACKGROUND: Mesenchymal stem cells (MSCs) may be used to treat steroid-refractory graft versus host disease (GVHD). However, the effects of MSCs in haploidentical peripheral blood stem cell transplantation (haplo-PBSCT) have not been confirmed in randomized studies. METHODS: We conducted a randomized clinical study to investigate the effects of pre-infusion (1 × 106 cells/kg) MSCs on hematopoietic recovery, Epstein-Barr and cytomegalovirus infection, GVHD, and relapse in patients undergoing haplo-PBSCT. Fifty patients with acute leukemia or myelodysplastic syndrome were randomly divided into an MSC group administered 1 × 106 MSCs/kg 4 to 6 hours before infusion of peripheral stem cells and a control group without MSCs. RESULTS: Mean platelet engraftment time was significantly faster in the MSC compared with the control group (12.28 vs 13.29 days). The mean neutrophil engraftment time was comparable in both groups (10.76 ± 2.40 vs. 10.29 ± 1.72 days). Grade II or above acute GVHD was significantly decreased in the MSC compared with the control group (12% vs. 36%). There were no significant differences in relapse rate or overall survival between the groups. CONCLUSION: These results suggest that pre-infusion single-dose MSCs promote platelet engraftment and decrease severe acute GVHD without increasing relapse rate.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32389803

RESUMO

With the COVID-19 pandemic and the ensuing barriers to the collection and transport of donor cells, it is often necessary to collect and cryopreserve grafts before initiation of transplantation conditioning. The effect on transplantation outcomes in nonmalignant disease is unknown. This analysis examined the effect of cryopreservation of related and unrelated donor grafts for transplantation for severe aplastic anemia in the United States during 2013 to 2019. Included are 52 recipients of cryopreserved grafts who were matched for age, donor type, and graft type to 194 recipients who received noncryopreserved grafts. Marginal Cox regression models were built to study the effect of cryopreservation and other risk factors associated with outcomes. We recorded higher 1-year rates of graft failure (hazard ratio [HR], 2.26; 95% confidence interval, 1.17 to 4.35; P = .01) and of 1-year overall mortality (HR, 3.13; 95% CI, 1.60 to 6.11; P = .0008) after transplantation of cryopreserved compared with noncryopreserved grafts, with adjustment for sex, performance score, comorbidity, cytomegalovirus serostatus, and ABO blood group match. The incidence of acute and chronic graft-versus-host disease did not differ between the 2 groups. Adjusted probabilities of 1-year survival were 73% (95% CI, 60% to 84%) in the cryopreserved graft group and 91% (95% CI, 86% to 94%) in the noncryopreserved graft group. These data support the use of noncryopreserved grafts whenever possible in patients with severe aplastic anemia.

4.
FASEB J ; 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32350948

RESUMO

During human erythroid maturation, Hsp70 translocates into the nucleus and protects GATA-1 from caspase-3 cleavage. Failure of Hsp70 to localize to the nucleus was found in Myelodysplastic syndrome (MDS) erythroblasts and can induce dyserythropoiesis, with arrest of maturation and death of erythroblasts. However, the mechanism of the nuclear trafficking of Hsp70 in erythroblasts remains unknown. Here, we found the hematopoietic transcriptional regulator, EDAG, to be a novel binding partner of Hsp70 that forms a protein complex with Hsp70 and GATA-1 during human normal erythroid differentiation. EDAG overexpression blocked the cytoplasmic translocation of Hsp70 induced by EPO deprivation, inhibited GATA-1 degradation, thereby promoting erythroid maturation in an Hsp70-dependent manner. Furthermore, in myelodysplastic syndrome (MDS) patients with dyserythropoiesis, EDAG is dramatically down-regulated, and forced expression of EDAG has been found to restore the localization of Hsp70 in the nucleus and elevate the protein level of GATA-1 to a significant extent. In addition, EDAG rescued the dyserythropoiesis of MDS patients by increasing erythroid differentiation and decreasing cell apoptosis. This study demonstrates the molecular mechanism of Hsp70 nuclear sustaining during erythroid maturation and establishes that EDAG might be a suitable therapeutic target for dyserythropoiesis in MDS patients.

5.
Zhongguo Gu Shang ; 33(4): 363-7, 2020 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-32351092

RESUMO

OBJECTIVE: To evaluate the effect of femoral and sciatic nerve block in total knee replacement of elderly patients under general anesthesia. METHODS: From July 2017 to July 2019, 60 patients with unilateral total knee replacement were selected, including 35 males and 25 females; aged 66 to 74(70.2±10.3) years;BMI 18 to 25 (21.3 ± 3.5) kg /m2;course 2 to 3 (1.2±0.3) days. The patients were divided into general anesthesia group (G group) 30 cases and general anesthesia plus nerve block group(GNB group) 30 cases. In GNB group, the femoral nerve sciatic nerve block was guided by ultrasound before anesthesia induction, 20 to 25 ml was injected into the femoral nerve puncture point with 0.5% ropivacaine, 15 to 20 ml was injected into the sciaticnerve puncture point, and the total volume was no more than 40 ml. Postoperative intravenous analgesia (PCIA) was performed in two groups. The dosage of propofol and remifentanil was recorded. Forty-eight hours after operation, the incidence of postoperative nausea and vomiting (PONV) and postoperative farsightedness were recorded. When VAS>3, tramadol 2 mg / kg was injected intravenously, and the additional times of tramadol were recorded. Forty-eight hours after operation, patients' satisfaction score was used to record the length of stay. RESULTS: Compared with group G, the dosage of propofol and remifentanil decreased, the incidence of PONV and the number of additional tramadol decreased, and the patients' satisfaction increased (P<0.05). There was no significant difference in the length of stay between two groups (P>0.05). The ROM and HSS scores of two groups after treatment were higher than those before treatment (P<0.05), and the VAS scores were lower than those before treatment (P<0.05). There was no significantdifference in ROM, VAS scores and HSS scores between two groups before treatment (P>0.05). The ROM and HSS scores of the GNB group after treatment were higher than those of the G group (P<0.05), and the VAS scores were lower than those of the G group (P<0.05). CONCLUSION: The application of femoral sciatic nerve block in total knee replacement under general anesthesia in elderly patients has good postoperative analgesic effect, and can reduce the dosage of general anesthesia, reduce PONV, and increase patient satisfaction.

6.
J Dig Dis ; 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32378783

RESUMO

BACKGROUND: The performance of digestive doctors to diagnose the traditional Chinese medicine (TCM) syndrome of functional dyspepsia (FD) is unknown in China. The aim of the study was to compare the diagnostic agreement of TCM syndromes of FD, including postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS) between the digestive doctors and TCM practitioners. METHODS: Patients with PDS or EPS were enrolled in six tertiary referral centers between January 2016 and December 2017. The TCM syndromes of the patients were first diagnosed by digestive doctors who performed TCM differential diagnosis based on the main symptoms. The TCM practitioners further diagnosed the TCM syndrome types of enrolled patients. The agreement of diagnosis between the digestive doctors and TCM practitioners was calculated. The demographic data and composition of TCM syndrome types were collected and analyzed. RESULTS: 160 patients including 81 PDS and 79 EPS were enrolled in this study. The total diagnosis consistency rate between the digestive doctors and TCM practitioners was 86.3%. The diagnosis consistency rate of PDS and EPS was 87.3% and 85.2%, respectively. The most common TCM syndrome type of PDS was liver-stomach disharmony syndrome (33.3%) and spleen-deficiency and Qi-stagnation syndrome (33.3%), while that for EPS was liver-stomach disharmony syndrome (36.7%). CONCLUSIONS: Digestive doctors had a high diagnostic agreement regarding the TCM syndrome types of FD based on the main symptoms differential diagnosis as compared to the TCM practitioners. This would aid the digestive doctors while selecting the Chinese patent medicine for FD based on syndrome differentiation. This article is protected by copyright. All rights reserved.

7.
J Diabetes Res ; 2020: 3695689, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32377518

RESUMO

Background: Banxia Xiexin Decoction (BXXD) reportedly regulates glycolipid metabolism and inhibits pancreatic ß-cell apoptosis. This study is aimed at investigating the protective effect of BXXD on tert-butyl hydroperoxide- (t-BHP-) induced apoptosis in MIN6 cells and the underlying mechanisms. Methods: MIN6 cells were preincubated with BXXD or liraglutide (Li) with or without PI3K inhibitor LY294002 (LY) for 12 h, following which t-BHP was added to induce MIN6 cell apoptosis. The protective effects of BXXD on MIN6 cells were evaluated by detecting cell viability and proliferation and glucose-stimulated insulin secretion (GSIS). The antiapoptotic effects were evaluated by Hoechst 33342 staining and terminal deoxynucleotidyl transferase dUTP nick end labeling assay (TUNEL). Malondialdehyde and glutathione peroxidase content and superoxide dismutase activity were measured using commercial kits. The expression of PI3K/AKT/FOXO1 signaling pathway-related signal molecules, and that of apoptotic indicators Bax, P27, and Caspase-3, was quantified using western blotting. Results: Preincubation with BXXD significantly improved t-BHP-induced proliferation inhibition and apoptosis and enhanced GSIS. t-BHP induced the generation of reactive oxygen species and inhibited the activities of antioxidant enzymes, which could be neutralized by pretreatment with BXXD. BXXD promoted the phosphorylation of AKT and FOXO1 in t-BHP-induced MIN6 cells. Moreover, BXXD attenuated the expression of related apoptotic indicators Bax, P27, and Caspase-3. LY abolished these effects of BXXD. Conclusion: BXXD protected MIN6 cells against t-BHP-induced apoptosis and improved insulin secretory function through modulation of the PI3K/AKT pathway and the downstream FOXO1, thus suggesting a novel therapeutic approach for type 2 diabetes mellitus (T2DM).

8.
Chem Rev ; 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32356657

RESUMO

Metal-organic frameworks (MOFs) are a class of distinctive porous crystalline materials constructed by metal ions/clusters and organic linkers. Owing to their structural diversity, functional adjustability, and high surface area, different types of MOF-based single metal sites are well exploited, including coordinately unsaturated metal sites from metal nodes and metallolinkers, as well as active metal species immobilized to MOFs. Furthermore, controllable thermal transformation of MOFs can upgrade them to nanomaterials functionalized with active single-atom catalysts (SACs). These unique features of MOFs and their derivatives enable them to serve as a highly versatile platform for catalysis, which has actually been becoming a rapidly developing interdisciplinary research area. In this review, we overview the recent developments of catalysis at single metal sites in MOF-based materials with emphasis on their structures and applications for thermocatalysis, electrocatalysis, and photocatalysis. We also compare the results and summarize the major insights gained from the works in this review, providing the challenges and prospects in this emerging field.

9.
J Cell Mol Med ; 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32391634

RESUMO

Acute myeloid leukaemia (AML) remains a therapeutic challenge and improvements in chemotherapy are needed. 4-Amino-2-trifluoromethyl-phenyl retinate (ATPR), a novel all-trans retinoic acid (ATRA) derivative designed and synthesized by our team, has been proven to show superior anticancer effect compared with ATRA on various cancers. However, its potential effect on AML remains largely unknown. Lactate dehydrogenase B (LDHB) is the key glycolytic enzyme that catalyses the interconversion between pyruvate and lactate. Currently, little is known about the role of LDHB in AML. In this study, we found that ATPR showed antileukaemic effects with RARα dependent in AML cells. LDHB was aberrantly overexpressed in human AML peripheral blood mononuclear cell (PBMC) and AML cell lines. A lentiviral vector expressing LDHB-targeting shRNA was constructed to generate a stable AML cells with low expression of LDHB. The effect of LDHB knockdown on differentiation and cycle arrest of AML cells was assessed in vitro and vivo, including involvement of Raf/MEK/ERK signalling. Finally, these data suggested that ATPR showed antileukaemic effects by RARα/LDHB/ ERK-glycolysis signalling axis. Further studies should focus on the underlying leukaemia-promoting mechanisms and investigate LDHB as a therapeutic target.

10.
Biomed Environ Sci ; 33(4): 227-237, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32438960

RESUMO

Objective: This study aimed to assess the association of waist circumference (WC) with all-cause mortality among Chinese adults. Methods: The baseline data were from Shanxi Province of 2002 China Nutrition and Health Survey. The death investigation and follow-up visit were conducted from December 2015 to March 2016. The visits covered up to 5,360 of 7,007 participants, representing a response rate of 76.5%. The Cox regression model and floating absolute risk were used to estimate hazard ratio and 95% floating CI of death by gender and age groups (≥ 60 and < 60 years old). Sensitivity analysis was performed by excluding current smokers; participants with stroke, hypertension, and diabetes; participants who accidentally died; and participants who died during the first 2 years of follow-up. Results: This study followed 67,129 person-years for 12.5 years on average, including 615 deaths. The mortality density was 916 per 100,000 person-years. Low WC was associated with all-cause mortality among men. Multifactor-adjusted hazard ratios ( HR) were 1.60 (1.35-1.90) for WC < 75.0 cm and 1.40 (1.11-1.76) for WC ranging from 75.0 cm to 79.9 cm. Low WC (< 70.0 cm and 70.0-74.9 cm) and high WC (≥ 95.0 cm) groups had a high risk of mortality among women. The adjusted HRs of death were 1.43 (1.11-1.83), 1.39 (1.05-1.84), and 1.91 (1.13-3.22). Conclusion: WC was an important predictor of death independent of body mass index (BMI). WC should be used as a simple rapid screening and predictive indicator of the risk of death.

11.
Eur J Obstet Gynecol Reprod Biol ; 250: 17-23, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32375083

RESUMO

OBJECTIVES: Healthy embryos and endometrial receptivity are keys to the success of in-vitro fertilization and embryo transfer (IVF-ET). Abnormal transvaginal ultrasonography (TVU) findings in the endometrium are a concern during assisted reproductive technology (ART) treatments. Observation of a hyperechogenic endometrial mass (HEM) during controlled ovarian stimulation (COS) in an IVF or intracytoplasmic sperm injection (ICSI) cycle is a dilemma. Here we investigated whether an HEM would affect ART cycle outcomes. STUDY DESIGN: We analyzed all data from patients who underwent IVF or ICSI treatment cycles from January 1, 2009 to December 31, 2016 at our institution. Patients diagnosed with an HEM were included. Each woman was matched with two control subjects of similar age (± 1 year), in terms of the number of cycles, type of infertility (primary or secondary), protocol used for COS, but with no HEM identified by TVU. Baseline characteristics, COS response, and pregnancy outcomes after ET were compared. RESULTS: In all, 1088 patients were diagnosed with an HEM. Of these, 426 met the inclusion criteria and were matched with 852 controls. Baseline characteristics showed no significant differences between the groups. The peak endometrial thickness was significantly greater in the experimental group than in the control group (1.15 ± 0.18 cm vs. 1.08 ± 0.21 cm, p < 0.001). The live birth rates were 43.7% vs 46.2% in the experimental and control groups, respectively. There were no significant between-group differences in the rates of biochemical or clinical pregnancy or abortions at any stage. CONCLUSIONS: Newly diagnosed HEMs < 18 mm in diameter monitored by TVU did not impair the outcomes of ART following COS in this study. If other conditions are suitable, completion of ART cycles should be the appropriate approach in such cases. KEY MESSAGE: Newly diagnosed hyperechogenic endometrial masses measuring <18 mm in diameter monitored by TVU during COS did not adversely affect the outcomes of these IVF/ICSI-ET cycles.

12.
Mov Disord ; 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32392383

RESUMO

BACKGROUND: Paroxysmal kinesigenic dyskinesia is a spectrum of involuntary dyskinetic disorders with high clinical and genetic heterogeneity. Mutations in proline-rich transmembrane protein 2 have been identified as the major pathogenic factor. OBJECTIVES: We analyzed 600 paroxysmal kinesigenic dyskinesia patients nationwide who were identified by the China Paroxysmal Dyskinesia Collaborative Group to summarize the clinical phenotypes and genetic features of paroxysmal kinesigenic dyskinesia in China and to provide new thoughts on diagnosis and therapy. METHODS: The China Paroxysmal Dyskinesia Collaborative Group was composed of departments of neurology from 22 hospitals. Clinical manifestations and proline-rich transmembrane protein 2 screening results were recorded using unified paroxysmal kinesigenic dyskinesia registration forms. Genotype-phenotype correlation analyses were conducted in patients with and without proline-rich transmembrane protein 2 mutations. High-knee exercises were applied in partial patients as a new diagnostic test to induce attacks. RESULTS: Kinesigenic triggers, male predilection, dystonic attacks, aura, complicated forms of paroxysmal kinesigenic dyskinesia, clustering in patients with family history, and dramatic responses to antiepileptic treatment were the prominent features in this multicenter study. Clinical analysis showed that proline-rich transmembrane protein 2 mutation carriers were prone to present at a younger age and have longer attack duration, bilateral limb involvement, choreic attacks, a complicated form of paroxysmal kinesigenic dyskinesia, family history, and more forms of dyskinesia. The new high-knee-exercise test efficiently induced attacks and could assist in diagnosis. CONCLUSIONS: We propose recommendations regarding diagnostic criteria for paroxysmal kinesigenic dyskinesia based on this large clinical study of paroxysmal kinesigenic dyskinesia. The findings offered some new insights into the diagnosis and treatment of paroxysmal kinesigenic dyskinesia and might help in building standardized paroxysmal kinesigenic dyskinesia clinical evaluations and therapies. © 2020 International Parkinson and Movement Disorder Society.

13.
Dev Cell ; 53(4): 473-491.e9, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32386599

RESUMO

The development of single-cell RNA sequencing (scRNA-seq) has allowed high-resolution analysis of cell-type diversity and transcriptional networks controlling cell-fate specification. To identify the transcriptional networks governing human retinal development, we performed scRNA-seq analysis on 16 time points from developing retina as well as four early stages of retinal organoid differentiation. We identified evolutionarily conserved patterns of gene expression during retinal progenitor maturation and specification of all seven major retinal cell types. Furthermore, we identified gene-expression differences between developing macula and periphery and between distinct populations of horizontal cells. We also identified species-specific patterns of gene expression during human and mouse retinal development. Finally, we identified an unexpected role for ATOH7 expression in regulation of photoreceptor specification during late retinogenesis. These results provide a roadmap to future studies of human retinal development and may help guide the design of cell-based therapies for treating retinal dystrophies.

14.
Mol Med Rep ; 22(1): 416-422, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32319667

RESUMO

Bisphenol A (BPA), a xenoestrogen commonly used in plastics, may act as an endocrine disruptor, which indicates that BPA might be a public health risk. The present study aimed to investigate the effect of BPA on 17ß­estradiol (E2)­mediated protection against liver ischemia/reperfusion (I/R) injury, and to identify the underlying mechanisms using a rat model. A total of 56 male Sprague Dawley rats were randomly divided into the following seven groups: i) Sham; ii) I/R; iii) Sham + BPA; iv) I/R + BPA; v) I/R + E2; vi) I/R + E2 + BPA; and vii) I/R + E2 + BPA + losartan [LOS; an angiotensin II (Ang II) type I receptor (ATIR) antagonist]. A rat model of hepatic I/R injury was established by inducing hepatic ischemia for 60 min followed by reperfusion for 24 h. When ischemia was induced, rats were treated with vehicle, E2, BPA or LOS. After 24 h of reperfusion, blood samples and hepatic tissues were collected for histopathological and biochemical examinations. The results suggested that 4 mg/kg BPA did not significantly alter the liver function, or Ang II and AT1R expression levels in the Sham and I/R groups. However, 4 mg/kg BPA inhibited E2­mediated hepatic protection by enhancing hepatic necrosis, and increasing the release of alanine transaminase, alkaline phosphatase and total bilirubin (P<0.05). Moreover, BPA increased serum and hepatic Ang II levels, as well as AT1R protein expression levels in the E2­treated rat model of liver I/R injury (P<0.05). LOS treatment reversed the negative effects of BPA on hepatic necrosis and liver serum marker levels, although it did not reverse BPA­mediated upregulation of serum and hepatic Ang II levels, or hepatic AT1R expression. Therefore, the present study suggested that BPA disrupted E2­mediated hepatic protection following I/R injury, but did not significantly affect healthy or I/R­injured livers; therefore, the mechanism underlying the effects of BPA may be associated with upregulation of the Ang II/AT1R signaling pathway.

15.
J Orthop Surg Res ; 15(1): 146, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32295616

RESUMO

BACKGROUND: Guzhi Zengsheng Zhitongwan (GZZSZTW) is an effective Chinese medicinal formulation for the treatment of osteoarthritis (OA) designed according to the "kidney governing bone" theory, which has been widely used as a golden guide for treating bone and cartilage diseases in traditional Chinese medicine. The aim of this study was to explore the molecular mechanism underlying its effects on the bone and kidney. METHODS: Preparation and quality control were performed as previously described. Since GZZSZTW is orally administered in the form of pills prepared in boiled water, the Chinese materia medica (CMM) mixture of this formula was extracted with distilled water by a reflux method and was then filtered through a 0.45-µm Hollow Fiber Cartridge (GE Healthcare, USA). The filtrate was freeze-dried by a Heto PowerDry LL3000 Freeze Dryer (Thermo, USA) and stored at - 80 °C. The effects of GZZSZTW on gene expression and regulation of both kidney and bone tissues were investigated using a state-of-the-art RNA-seq technology. RESULTS: We demonstrated that GZZSZTW could enhance kidney function and suppress bone formation and resorption by modulating the activities of osteoblast and osteoclast, and might subsequently contribute to the inhibition of osteophyte formation during the process of OA. These effects might be achieved by the synergistic interactions of various herbs and their active components in GZZSZTW, which increased the expression levels of functional genes participating in kidney function, regulation, and repair, and then decreased the expression levels of genes involved in bone formation and resorption. Thus, our findings were consistent with the "kidney governing bone" theory, which has been widely used as a guide in clinical practice for thousands of years. CONCLUSIONS: This study has deepened the current knowledge about the molecular effects of GZZSZTW on bone and kidney regulation. Furthermore, this study might be able to provide possible strategies to further prevent and treat joint diseases by using traditional Chinese medicinal formulations following the "kidney governing bone" theory.

16.
Macromol Rapid Commun ; : e2000001, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32297420

RESUMO

In order to improve the poor solvent resistance and poor temperature resistance caused by traditional sizing agents, crystalline poly(ether ether ketone) (PEEK) is introduced to the interfacial phases of carbon fiber (CF) reinforced PEEK composites by a soluble precursor named PEEK-1,3-dioxolane. By changing the soluble precursor molecular weight and concentration in the sizing solution, the content of PEEK coated on the CF fiber surface can be controlled and the different interfacial properties of the PEEK composites can be obtained. The results shows that, with this method, crystalline PEEK can be completely coated on the CF surface, and the interfacial shear strength of the PEEK composites increases from 43.42 to 83.13 MPa. Due to none of any soluble compounds in the PEEK composites, the interfacial layer is well preserved under organic solvents and hygrothermal conditions, and the interfacial shear strength (IFSS) of the PEEK composites maintained above 85.4% and 90.44%, respectively. Scanning electron microscope clarifies that the mechanism of interface enhancement comes from a better wetting of crystalline PEEK on the fiber surface. Additionally, the sizing system of this investagation has the potential commercial value because of no toxic reagent (such as 2,4,5-trichloro-1-hydroxy-benzene or concentrated sulfuric acid) is required during sizing.

17.
Sci Rep ; 10(1): 6522, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32300174

RESUMO

Moso bamboo (Phyllostachysheterocycla (Carr.) Mitford cv. Pubescens) is an economically valuable plant in bamboo production areas of southern China, for which the management mode is crucial for improving the comprehensive benefits of bamboo forest stands. In this respect, mixed forested areas of bamboo and broad-leaved tree species can provide sound ecological management of bamboo in forestry operations. To further this goal, an outstanding question is to better understand the spatial distribution of soil bacterial communities in relation to the proportion of mixed in bamboo and broad-leaved forest. We analyzed soil bacterial community diversity and composition along a proportional gradient of 0-40% mixed-ratio (as represented by the width and size of the broad-leaved tree crown over the plot area) of bamboo and broad-leaved forest in Tianbao Yan Nature Reserve using the highthroughputsequencing of the 16S rRNA gene.Specifically, the sampling plots for the mixed proportions were divided according to the percentage of summed projected area of live broadleaf tree crowns. The main broad-leaved species in the five mixed ratio plots are the same. Each plot was 20 m × 20 m in size, and a total of 15 plots were established, three per forest ratio class. From each plot, soil samples were taken at the surface (0-10 cm depth) in December 2017. Our analysis revealed that soil bacterial diversity community structure and dominant flora changed under different mixing ratios of bamboo and broad-leaved trees. In the stand with a mixed ratio of 10-20%, the bacterial diversity index is higher; however, the diversity was lowest in the 20-30% stands. Among the 20-30% forest soil, Acidobacteria (Solibacteria, Solibacteriales, Acidobacteriales) was more abundant than in soils from other mixed-ratio stands.Redundancy analysis showed that mixed forest stand structure, soil pH, organic carbon, total nitrogen, and soil moisture all contributed to shaping the bacterial community structure. Changes in microbial communities were associated with species diversity in tree layers, availability of soil nutrients (SOC and TN), and changes in soil physical properties (MS, pH). Together, these empirical results suggest that different mixing ratios in the bamboo-broad-leaved mixed forest could influence the soil bacterial community structure indirectly, specifically by affecting the soil physical and chemical properties of the forest.

18.
FASEB J ; 2020 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-32304342

RESUMO

Our understanding of the molecular mechanisms underlying adaptations to resistance exercise remains elusive despite the significant biological and clinical relevance. We developed a novel voluntary mouse weightlifting model, which elicits squat-like activities against adjustable load during feeding, to investigate the resistance exercise-induced contractile and metabolic adaptations. RNAseq analysis revealed that a single bout of weightlifting induced significant transcriptome responses of genes that function in posttranslational modification, metabolism, and muscle differentiation in recruited skeletal muscles, which were confirmed by increased expression of fibroblast growth factor-inducible 14 (Fn14), Down syndrome critical region 1 (Dscr1) and Nuclear receptor subfamily 4, group A, member 3 (Nr4a3) genes. Long-term (8 weeks) voluntary weightlifting training resulted in significantly increases of muscle mass, protein synthesis (puromycin incorporation in SUnSET assay) and mTOR pathway protein expression (raptor, 4e-bp-1, and p70S6K proteins) along with enhanced muscle power (specific torque and contraction speed), but not endurance capacity, mitochondrial biogenesis, and fiber type transformation. Importantly, weightlifting training profound improved whole-body glucose clearance and skeletal muscle insulin sensitivity along with enhanced autophagy (increased LC3 and LC3-II/I ratio, and decreased p62/Sqstm1). These data suggest that resistance training in mice promotes muscle adaptation and insulin sensitivity with simultaneous enhancement of autophagy and mTOR pathway.

19.
Toxicology ; 438: 152460, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32278050

RESUMO

Synthetic pyrethroids are used as insecticides in agriculture and a variety of household applications worldwide. Pyrethroids are widely distributed in all environmental compartments and the general populations are exposed to pyrethroids through various routes. Pyrethroids have been identified as endocrine-disrupting chemicals (EDCs) which are responsible for the male reproductive impairments. The data confirm pyrethroids cause male reproductive damages. The insecticides exert the toxic effects on male reproductive system through various complex mechanisms including antagonizing androgen receptor (AR), inhibiting steroid synthesis, affecting the hypothalamic-pituitary-gonadal (HPG) axis, acting as estrogen receptor (ER) modulators and inducing oxidative stress. The mechanisms of male reproductive toxicity of pyrethroids involve multiple targets and pathways. The review will provide further insight into pyrethroid-induced male reproductive toxicity and mechanisms, which is crucial to preserve male reproductive health.

20.
Artigo em Inglês | MEDLINE | ID: mdl-32283185

RESUMO

The COVID-19 pandemic has created significant barriers to timely donor evaluation, cell collection, and graft transport for allogeneic hematopoietic stem cell transplantation (allo-HCT). To ensure availability of donor cells on the scheduled date of infusion, many sites now collect cryopreserved grafts before the start of pretransplantation conditioning. Post-transplantation cyclophosphamide (ptCY) is an increasingly used approach for graft-versus-host disease (GVHD) prophylaxis, but the impact of graft cryopreservation on the outcomes of allo-HCT using ptCY is not known. Using the Center for International Blood and Marrow Transplant Research (CIBMTR) database, we compared the outcomes of HCT using cryopreserved versus fresh grafts in patients undergoing HCT for hematologic malignancy with ptCY. We analyzed 274 patients with hematologic malignancy undergoing allo-HCT between 2013 and 2018 with cryopreserved grafts and ptCY. Eighteen patients received bone marrow grafts and 256 received peripheral blood stem cell grafts. These patients were matched for age, graft type, disease risk index (DRI), and propensity score with 1080 patients who underwent allo-HCT with fresh grafts. The propensity score, which is an assessment of the likelihood of receiving a fresh graft versus a cryopreserved graft, was calculated using logistic regression to account for the following: disease histology, Karnofsky Performance Score (KPS), HCT Comorbidity Index, conditioning regimen intensity, donor type, and recipient race. The primary endpoint was overall survival (OS). Secondary endpoints included acute and chronic graft-versus-host disease (GVHD), non-relapse mortality (NRM), relapse/progression and disease-free survival (DFS). Because of multiple comparisons, only P values <.01 were considered statistically significant. The 2 cohorts (cryopreserved and fresh) were similar in terms of patient age, KPS, diagnosis, DRI, HCT-CI, donor/graft source, and conditioning intensity. One-year probabilities of OS were 71.1% (95% confidence interval [CI], 68.3% to 73.8%) with fresh grafts and 70.3% (95% CI, 64.6% to 75.7%) with cryopreserved grafts (P = .81). Corresponding probabilities of OS at 2 years were 60.6% (95% CI, 57.3% to 63.8%) and 58.7% (95% CI, 51.9% to 65.4%) (P = .62). In matched-pair regression analysis, graft cryopreservation was not associated with a significantly higher risk of mortality (hazard ratio [HR] for cryopreserved versus fresh, 1.05; 95% CI, .86 to 1.29; P = .60). Similarly, rates of neutrophil recovery (HR, .91; 95% CI, .80 to 1.02; P = .12), platelet recovery (HR, .88; 95% CI, .78 to 1.00; P = .05), grade III-IV acute GVHD (HR, .78; 95% CI, .50 to 1.22; P = .27), NRM (HR, 1.16; 95% CI, .86 to 1.55; P = .32) and relapse/progression (HR, 1.21; 95% CI, .97 to 1.50; P = .09) were similar with cryopreserved grafts versus fresh grafts. There were somewhat lower rates of chronic GVHD (HR, 78; 95% CI, .61 to .99; P = .04) and DFS (HR for treatment failure, 1.19; 95% CI, 1.01 to 1.29; P = .04) with graft cryopreservation that were of marginal statistical significance after adjusting for multiple comparisons. Overall, our data indicate that graft cryopreservation does not significantly delay hematopoietic recovery, increase the risk of acute GVHD or NRM, or decrease OS after allo-HCT using ptCY.

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