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1.
Biochim Biophys Acta Mol Basis Dis ; 1866(1): 165554, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31513833

RESUMO

Activation of interferon (IFN)-I signaling in B cells contributes to the pathogenesis of systemic lupus erythematosus (SLE). Recent studies have shown that myeloid-derived suppressor cells (MDSCs) significantly expand in SLE patients and lupus-prone MRL/lpr mice and contribute to the pathogenesis of SLE. However, the role of SLE-derived MDSCs in regulating IFN-I signaling activation of B cells remains unknown. Here, we demonstrate that expansions of MDSCs, including granulocyte (G)-MDSCs and monocytic (M)-MDSCs, during the progression of SLE were correlated with the IFN-I signature of B cells. Interestingly, G-MDSCs from MRL/lpr mice, but not M-MDSCs, could significantly promote IFN-I signaling activation of B cells and contribute to the pathogenesis of SLE. Mechanistically, we identified that the long non-coding RNA NEAT1 was over-expressed in G-MDSCs from MRL/lpr mice and could induce the promotion of G-MDSCs on IFN-I signaling activation of B cells through B cell-activating factor (BAFF) secretion. Importantly, NEAT1 deficiency significantly attenuated the lupus symptoms in pristane-induced lupus mice. In addition, there was a positive correlation between NEAT1 and BAFF with the IFN signature in SLE patients. In conclusion, G-MDSCs may contribute to the IFN signature in SLE B cells through the NEAT1-BAFF axis, highlighting G-MDSCs as a potential therapeutic target to treat SLE.

2.
Theor Appl Genet ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31720702

RESUMO

KEY MESSAGE: A total of 12 QTL conferring resistance to tan spot induced by a race 2 isolate, 86-124, were identified in three tetraploid wheat mapping populations. Durum is a tetraploid species of wheat and an important food crop. Tan spot, caused by the necrotrophic fungal pathogen Pyrenophora tritici-repentis (Ptr), is a major foliar disease of both tetraploid durum wheat and hexaploid bread wheat. Understanding the Ptr-wheat interaction and identifying major QTL can facilitate the development of resistant cultivars and effectively mitigate the negative effect of this disease. Over 100 QTL have already been discovered in hexaploid bread wheat, whereas few mapping studies have been conducted in durum wheat. Utilizing resistant resources and identifying novel resistant loci in tetraploid wheat will be beneficial for the development of tan spot-resistant durum varieties. In this study, we evaluated four interconnected tetraploid wheat populations for their reactions to the race 2 isolate 86-124, which produces Ptr ToxA. Tsn1, the wheat gene that confers sensitivity to Ptr ToxA, was not associated with tan spot severity in any of the four populations. We found a total of 12 tan spot-resistant QTL among the three mapping populations. The QTL located on chromosomes 3A and 5A were detected in multiple populations and co-localized with race-nonspecific QTL identified in other mapping studies. Together, these QTL can confer high levels of resistance and can be used for the improvement in tan spot resistance in both hexaploid bread and durum wheat breeding. Two QTL on chromosomes 1B and 7A, respectively, were found in one population when inoculated with a ToxA knockout strain 86-124ΔToxA only, indicating that their association with tan spot was induced by other unidentified necrotrophic effectors, but under the absence of Ptr ToxA. In addition to removal of the known dominant susceptibility genes, integrating major race-nonspecific resistance loci like the QTL identified on chromosome 3A and 5A in this study could confer high and stable tan spot resistance in durum wheat.

3.
Phytopathology ; 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31609681

RESUMO

Spot blotch caused by Bipolaris sorokiniana and powdery mildew caused by Blumeria graminis f. sp. hordei (Bgh) are two important diseases of barley. To map genetic loci controlling susceptibility and resistance to these diseases, a mapping population consisting of 133 recombinant inbred lines (RILs) was developed from the cross between Bowman and ND5883. A genetic map was constructed for the population with 852 unique single nucleotide polymorphism (SNP) markers generated by sequencing-based genotyping. Bowman and ND5883 showed distinct infection responses (IRs) at the seedling stage to two isolates (ND90Pr and ND85F) of B. sorokiniana and one isolate (Race I) of Bgh. Genetic analysis of the RILs revealed one major gene (Scs6) controls susceptibility to B. sorokiniana isolate ND90Pr and another major gene (Mla8) confers resistance to Bgh isolate Race I, respectively. Scs6 was mapped on chromosome 1H of Bowman as previously reported. Mla8 was also mapped to the short arm of 1H, which was tightly linked but not allelic to the Rcs6/Scs6 locus. QTL analysis identified two QTL, QSbs-1H-P1 and QSbs-7H-P1, responsible for susceptibility to spot blotch caused by B. sorokiniana isolate ND85F in ND5883, which are located on chromosome 1H and 7H, respectively. QSbs-7H-P1 was mapped to the same region as Rcs5, while QSbs-1H-P1 may represent a novel allele conferring seedling stage susceptibility to isolate ND85F. Identification and molecular mapping of the loci for spot blotch susceptibility and powdery mildew resistance will facilitate development of barley cultivars with resistance to the diseases.

4.
Sci Rep ; 9(1): 14974, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628344

RESUMO

Sunflower (Helianthus annuus L.) production is challenged by different biotic and abiotic stresses, among which downy mildew (DM) is a severe biotic stress that is detrimental to sunflower yield and quality in many sunflower-growing regions worldwide. Resistance against its infestation in sunflower is commonly regulated by single dominant genes. Pl17 and Pl19 are two broad-spectrum DM resistance genes that have been previously mapped to a gene cluster spanning a 3.2 Mb region at the upper end of sunflower chromosome 4. Using a whole-genome resequencing approach combined with a reference sequence-based chromosome walking strategy and high-density mapping populations, we narrowed down Pl17 to a 15-kb region flanked by SNP markers C4_5711524 and SPB0001. A prospective candidate gene HanXRQChr04g0095641 for Pl17 was identified, encoding a typical TNL resistance gene protein. Pl19 was delimited to a 35-kb region and was approximately 1 Mb away from Pl17, flanked by SNP markers C4_6676629 and C4_6711381. The only gene present within the delineated Pl19 locus in the reference genome, HanXRQChr04g0095951, was predicted to encode an RNA methyltransferase family protein. Six and eight SNP markers diagnostic for Pl17 and Pl19, respectively, were identified upon evaluation of 96 diverse sunflower lines, providing a very useful tool for marker-assisted selection in sunflower breeding programs.

5.
ChemSusChem ; 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31647183

RESUMO

The efficient hydrodeoxygenation (HDO) of lignin-derived oxygenates is essential but challenging owing to the inherent complexity of feedstock and the lack of effective catalytic approaches. A catalytic strategy has been developed that separates C-O hydrogenolysis and aromatic hydrogenation on different active catalysts with interoperation that can achieve high oxygen removal in lignin-derived oxygenates. The flexible use of tungsten carbide for C-O bond cleavage and a nickel catalyst with controlled particle size for arene hydrogenation enables the tunable production of cyclohexane and cyclohexanol with almost full conversion of guaiacol. Such integration of dual catalysts in close proximity enables superior HDO of bio-oils into liquid alkanes with high mass and carbon yields of 27.9 and 45.0 wt %, respectively. This finding provides a new effective strategy for practical applications.

6.
Front Immunol ; 10: 1824, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31428103

RESUMO

Macrophages play a critical role in the pathogenesis of endotoxin shock by producing excessive amounts of pro-inflammatory cytokines. A pan-caspase inhibitor, zVAD, can be used to induce necroptosis under certain stimuli. The role of zVAD in both regulating the survival and activation of macrophages, and the pathogenesis of endotoxin shock remains not entirely clear. Here, we found that treatment of mice with zVAD could significantly reduce mortality and alleviate disease after lipopolysaccharide (LPS) challenge. Notably, in LPS-challenged mice, treatment with zVAD could also reduce the percentage of peritoneal macrophages by promoting necroptosis and inhibiting pro-inflammatory responses in macrophages. In vitro studies showed that pretreatment with zVAD promoted LPS-induced nitric oxide-mediated necroptosis of bone marrow-derived macrophages (BMDMs), leading to reduced pro-inflammatory cytokine secretion. Interestingly, zVAD treatment promoted the accumulation of myeloid-derived suppressor cells (MDSCs) in a mouse model of endotoxin shock, and this process inhibited LPS-induced pro-inflammatory responses in macrophages. Based on these findings, we conclude that treatment with zVAD alleviates LPS-induced endotoxic shock by inducing macrophage necroptosis and promoting MDSC-mediated inhibition of macrophage activation. Thus, this study provides insights into the effects of zVAD treatment in inflammatory diseases, especially endotoxic shock.

7.
Gen Comp Endocrinol ; 281: 83-90, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-31170402

RESUMO

The function of insulin-like growth factor (Igf) system in ovary has attracted much attention, but the role of Igf binding proteins (Igfbps) in ovary is still largely unknown. In this study, the role of Igfbps in oocyte maturation was investigated in zebrafish. The expression of all eight identified Igfbps except Igfbp6b could be detected in the adult ovary and exhibited differential expression profiles during folliculogenesis. The expression of several Igfbps is dynamically changed during oocyte maturation induced by human chorionic gonadotropin (hCG). By treatment of an Igfbps inhibitor NBI-31772 in vitro, the oocyte maturation could be stimulated in a clear dose-, time- and stage-dependent manner. Such effects were also observed by administration of NBI-31772 in vivo. Igfbps are differentially expressed in both follicular cells and oocytes, but the effect of NBI-31772 could only be found in intact follicles and not in the denuded oocytes. Previous studies have demonstrated that Igf3 is the major Igf member in regulating oocyte maturation of zebrafish. Interestingly, NBI-31772 could increase the effect of Igf3 on oocyte maturation. Furthermore, we found the effect of NBI-31772 on oocyte maturation could be blocked by an Igf type 1 receptor inhibitor BMS-536924 in vitro, suggesting the Igfbps can inhibit the oocyte maturation via Igf/Igf1r pathway. Together, we provided the first evidence in fish that Igfbps inhibit oocyte maturation of zebrafish.

8.
Int Immunopharmacol ; 74: 105691, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31252248

RESUMO

BACKGROUND: A meta-analysis was performed to assess the risk of common adverse events in melanoma patients treated with checkpoint inhibitors. METHODS: Eligible studies were downloaded from PubMed, Embase, and Cochrane databases based on an established strategy. Review manager version 5.3 was used to analyze data. RESULTS: After exclusion of ineligible studies, six studies were finally included in the meta-analysis, which comprised of 2136 patients in intervention group and 1773 patients in control group. There was a difference in low grade risk of pruritus (OR 5.63, 95% CI 2.92-10.85, P < 0.00001), diarrhea/colitis (OR 1.51, 95% CI 1.09-2.09, P = 0.01), but not fatigue (low grade, OR 0.96, 95% CI 0.72-1.29, P = 0.80; high grade, OR 0.72, 95% CI 0.23-2.24, P = 0.57) and some high grade risk between the intervention group and control group. Subgroups analysis revealed that low grade risk of pruritus (OR 8.17, 95% CI 4.29-15.55, P < 0.00001) and high grade risk of pruritus (OR 7.08, 95% CI 1.25-40.09, P = 0.03) were significantly different between patients treated with chemotherapy and those treated with checkpoint inhibitors. But fatigue and diarrhea/colitis were not different between the two groups. CONCLUSION: Checkpoint inhibitors are associated with a higher risk in some side effects than chemotherapy in melanoma patients. Therefore, strategies that reduce the risk of adverse events in patients taking checkpoint inhibitors should be developed.

9.
ChemSusChem ; 12(14): 3271-3277, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31038822

RESUMO

Catalytic lignosulfonate valorization is hampered by the in situ liberation of sulfur that ultimately poisons the catalyst. To overcome this limitation, metal sulfide catalysts were developed that are able to cleave the C-O bonds of lignosulfonate and are resistant to sulfur poisoning. The catalysts were prepared by using the lignosulfonate substrate as a precursor to form well-dispersed carbon-supported metal (Co, Ni, Mo, CoMo, NiMo) sulfide catalysts. Following optimization of the reaction conditions employing a model substrate, the catalysts were used to generate guaiacyl monomers from lignosulfonate. The Co catalyst was able to produce 23.7 mg of 4-propylguaiacol per gram of lignosulfonate with a selectivity of 84 %. The catalysts operated in water and could be recycled and reused multiple times. Thus, it was demonstrated that an inexpensive, sulfur-tolerant catalyst based on an earth-abundant metal and lignosulfonate efficiently catalyzed the selective hydrogenolysis of lignosulfonate in water in the absence of additives.

10.
Front Immunol ; 10: 215, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30809230

RESUMO

Dysregulation of macrophage has been demonstrated to contribute to aberrant immune responses and inflammatory diseases. CD11b, expressed on macrophages, plays a critical role in regulating pathogen recognition, phagocytosis, and cell survival. In the present study, we explored the effect of leukadherin-1 (LA1), an agonist of CD11b, on regulating LPS-induced pro-inflammatory response in macrophages and endotoxic shock. Intriguingly, we found that LA1 could significantly reduce mortalities of mice and alleviated pathological injury of liver and lung in endotoxic shock. In vivo studies showed that LA1-induced activation of CD11b significantly inhibited the LPS-induced pro-inflammatory response in macrophages of mice. Moreover, LA1-induced activation of CD11b significantly inhibited LPS/IFN-γ-induced pro-inflammatory response in macrophages by inhibiting MAPKs and NF-κB signaling pathways in vitro. Furthermore, the mice injected with LA1-treated BMDMs showed fewer pathological lesions than those injected with vehicle-treated BMDMs in endotoxic shock. In addition, we found that activation of TLR4 by LPS could endocytose CD11b and activation of CD11b by LA1 could endocytose TLR4 in vitro and in vivo, subsequently blocking the binding of LPS with TLR4. Based on these findings, we concluded that LA1-induced activation of CD11b negatively regulates LPS-induced pro-inflammatory response in macrophages and subsequently protects mice from endotoxin shock by partially blocking LPS-TLR4 interaction. Our study provides a new insight into the role of CD11b in the pathogenesis of inflammatory diseases.

11.
Biochim Biophys Acta Mol Basis Dis ; 1865(3): 535-546, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30557700

RESUMO

Myeloid-derived suppressor cells (MDSCs) play an immunosuppressive role in the pathogenesis of inflammatory diseases. CD180, a TLR-like protein, can regulate the proliferation and activation of immune cells. However, the roles of CD180 in regulating the accumulation and function of MDSCs have not been investigated. Here, we found that, compared with non-treated controls, the expression of CD180 was significantly elevated in MDSCs, especially granulocytic MDSCs (G-MDSCs), from mice challenged with lipopolysaccharide (LPS). Ligation of CD180 by the anti-CD180 antibody not only blocked the expansion of MDSCs by preventing the phosphorylation of signal transducer and activator of transcription 3 (STAT3), but also reduced the immunosuppressive activity of MDSCs on M1 macrophage polarization through inhibition of Arg-1 expression in vitro. In vivo studies showed that injection of anti-CD180 antibody significantly aggravated pathological lesions in mice challenged with LPS. Furthermore, injection of anti-CD180 antibody inhibited the accumulation of G-MDSCs in mice challenged with LPS and reduced the immunosuppressive activity of G-MDSCs on M1 macrophage polarization. Based on these findings, we conclude that ligation of CD180 contributes to the pathogenesis of endotoxic shock by inhibiting the accumulation and immunosuppressive activity of G-MDSCs, thus providing insight into the function of CD180 in inflammatory diseases.


Assuntos
Anticorpos Monoclonais/farmacologia , Antígenos CD/imunologia , Células Supressoras Mieloides/imunologia , Fator de Transcrição STAT3/fisiologia , Choque Séptico/induzido quimicamente , Choque Séptico/imunologia , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Feminino , Inflamação/induzido quimicamente , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células Supressoras Mieloides/citologia , Células Supressoras Mieloides/efeitos dos fármacos , Ligação Proteica , Choque Séptico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia
12.
Front Immunol ; 9: 2643, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30498494

RESUMO

Activation of TLR7 and TLR9 by endogenous RNA- or DNA-containing ligands, respectively, can lead to hyper-activation of immune cells, including macrophages and DCs, subsequently contributes to the pathogenesis of SLE. CD180, a TLR-like protein, is specifically involved in the development and activation of immune cells. Our previous study and others have reported that CD180-negative B cells are dramatically increased in SLE patients and responsible for the production of auto-antibodies. However, the mode of CD180 expression on macrophages and DCs in SLE remains unclear and the role of CD180 on regulating TLR7- and TLR9-mediated activation of macrophages and DCs are largely unknown. In the present study, we found that the percentages of CD180-negative macrophages and DCs were both increased in SLE patients and lupus-prone MRL/lpr mice compared with healthy donors and wild-type mice, respectively. Notably, ligation of CD180 significantly inhibited the activation of TLR7 and TLR9 signaling pathways in macrophages and DCs through the Lyn-SHP-1/2 axis. What's more, injection of anti-CD180 Ab could markedly ameliorate the lupus-symptoms of imiquimod-treated mice and lupus-prone MRL/lpr mice through inhibiting the activation of macrophages and DCs. Collectively, our results highlight a critical role of CD180 in regulating TLR7- and TLR9-mediated activation of macrophages and DCs, hinting that CD180 can be regarded as a potential therapeutic target for SLE treatment.

13.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 34(11): 961-968, 2018 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-30591103

RESUMO

Objective To study the effect of CD11b agonist leukadherin-1 (LA1) on the aggregation and immunosuppressive function of myeloid-derived suppressor cells (MDSCs) and its therapeutic effect on the condition of endotoxic shock mice. Methods The percentages of MDSCs , granulocytic myeloid-derived suppressor cells(G-MDSCs)and monocytic myeloid-derived suppressor cells(M-MDSCs)in spleen were detected by flow cytometry, after C57BL/6 female mice were injected of LA1 to activate through abdominal cavity for 12 hours and 48 hours. MDSCs were induced from the femur and tibia of C57BL/6 female mice in vitro. The expression levels of immunosuppressive related factors, such as interleukin 10 (IL-10), NADPH oxidase 1 (NOX1) and inducible nitric oxide synthase (iNOS) , were detected by real time quantitative PCR. C57BL/6 female mice were randomly divided into PBS group, LA1 group, PBS combined LPS group and LA1 combined LPS group. Flow cytometry was utilized to detect the ratio changes of MDSCs, G-MDSCs and M-MDSCs as well as the expression of CD86 and CD40 in macrophage, hematoxylin-eosin staining of lung and liver was utilized to detect the pathological injury, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling(TUNEL)was used to detect the apoptosis of pneumonocyte and hepatocyte and mortality analysis was reflected the severity of the disease. Based on the above indicators, we analyzed the effects of LA1 on the aggregation of MDSCs and the condition of mice in endotoxic shock. Results The ratio of MDSCs was increased by LA1 treatment for 12 and 48 hours. Further analysis of the proportions of G-MDSCs showed that LA1 treatment for 12 hours increased the proportions of G-MDSCs compared with the control group. In vitro, mRNA levels of IL-10, NOX1 and iNOS were increased after LA1 treatment in MDSCs. In vivo experiments, compared with the PBS combined LPS group, the proportions of MDSCs and G-MDSCs in LA1 combined LPS group were increased, the injuries of liver and lung were alleviated, the mortalities were reduced, and the activations of macrophage were decreased. Conclusion The activation of CD11b by LA1 alleviates endotoxin shock by promoting the aggregation of MDSCs and the expression of immunosuppressive related factors.


Assuntos
Benzoatos/farmacologia , Antígeno CD11b/agonistas , Células Supressoras Mieloides/citologia , Choque Séptico/tratamento farmacológico , Tioidantoínas/farmacologia , Animais , Feminino , Interleucina-10/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NADPH Oxidase 1/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Distribuição Aleatória , Baço/citologia
14.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 34(8): 695-701, 2018 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-30384867

RESUMO

Objective To investigate the role of interleukin-16 (IL-16) in the development of inflammatory bowel disease (IBD) and clarify its regulatory mechanism involved in the pathogenesis of IBD. Methods Seven-week-old wild-type C57BL/6 (WT) and IL-16 knockout (IL-16-/-) female mice were divided into WT control group, WT dextran sulfate sodium (DSS) treatment group, IL-16-/- control group and IL-16-/- DSS treatment group. The DSS model groups were given the water with 25 g/L DSS for 7 days to establish the IBD models, while the control groups were given the normal water. During the modeling period, the body mass of mice was recorded to calculate the body mass curve. After 7 days, the whole colon of the mice was dissected and the level of IL-16 mRNA in the colon tissue was detected by real-time PCR. The level of IL-16 protein in the colon tissue was detected by ELISA. The expression and localization of IL-16 in the colon tissue were observed by immunofluorescence technique. HE staining was used to detect colonic pathological injury in mice. TUNEL assay was used to detect cell apoptosis of the colon tissue. Flow cytometry was used to detect the number and polarization of macrophages in peritoneal cells (F4/80, CD86). Immunohistochemical staining was used to detect the distribution of macrophages in the colon tissues. Real-time PCR was used to detect IL-6 and IL-12 mRNA levels in the colon tissue, and IL-6 and IL-12 protein levels were detected by ELISA. Results DSS induced high expression of IL-16 in the colon tissue. Compared with WT DSS treatment group, IL-16-/- DSS treatment group showed less changes in body mass, less colon tissue damage, and markedly lower percents of apoptotic cells in the peritoneal or colonic tissues of IL-16-/- mice. What's more, the number of macrophages, the polarization level of M1 macrophages, and the levels of the iconic inflammatory factors IL-6 and IL-12 significantly decreased in IL-16-/- DSS treatment group compared with WT DSS treatment group. Conclusion IL-16 can aggravate DSS-induced IBD by promoting the polarization of M1 macrophages.

15.
Biol Reprod ; 2018 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-30418488

RESUMO

The role of androgenic steroids on ovarian development has attracted much attention in recent years, but the molecular mechanism is still largely unknown. In this study, using zebrafish as a model, we found that the trace metal zinc mediates the action of androgen on oocyte maturation. The ovarian and serum testosterone is transiently stimulated by LH during oocyte maturation. Testosterone could mimic the action of LH on oocyte maturation, and its action appears to be independent of the classical nuclear androgen receptor. Consistent with a recent finding that a zinc transporter (Zip9) has been suggested as a novel androgen receptor, we found the labile zinc concentration could be induced by testosterone in the ovarian follicular cells, and zinc could mimic the action of testosterone on oocyte maturation and signaling. Moreover, the action of testosterone on oocyte maturation could be abolished by the chelation of zinc. Thus, the evidence support the notion that zinc could mediate the action of androgen on oocyte maturation in zebrafish. This finding would shed light on understanding the role of androgen in ovary development and the molecular mechanism of oocyte maturation in fish.

16.
Med Sci Monit Basic Res ; 24: 141-145, 2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-30262799

RESUMO

BACKGROUND Diabetic cardiomyopathy (DCM) is a common but underestimated cause of heart failure in patients with diabetes. This study investigated the myocardial-protective effects of nicorandil (Nic) on rats with DCM. MATERIAL AND METHODS A total of forty-seven 180-220 g male Wistar rats were randomly divided into 4 groups: a control group (control, n=8), a DCM group (DCM, n=13), a nicorandil-pretreated DCM group (Nic1, n=13), and a nicorandil-treated DCM group (Nic2, n=13). A rat model of type 2 diabetes was induced by high-fat and high-sugar diet and intraperitoneal injection of streptozotocin (STZ). Nicorandil (3 mg/kg/d) was orally administrated to rats in the Nic1 group starting at week 4. Nicorandil (3 mg/kg/d) was orally administrated only after the induction of diabetes in the Nic2 group. The serum lipoids, plasma glucose, insulin levels, heart weight index, serum creatine kinase (CK), lactate dehydrogenase (LDH) levels, superoxide dismutase (SOD) activity, and malondialdehyde (MDA) were analyzed in all groups. RESULTS The DCM group showed increased heart weight index, serum LDH, CK, and MDA content and decreased serum SOD activity, as compared with the control group (P<0.05). The DCM-induced increases in heart weight index, serum LDH, CK, and MDA content and decrease in serum SOD activity were attenuated in both Nic1 and Nic2 groups (P<0.05). However, there was no significant difference between Nic1 and Nic2 groups (P>0.05). CONCLUSIONS Nicorandil has protective effects on cardiac hypertrophy in DCM rats through increased SOD activity and decreased MDA content. Therefore, nicorandil may be a therapeutic method for diabetic patients with DCM.

17.
Rev Sci Instrum ; 89(8): 085110, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30184705

RESUMO

Local mean decomposition (LMD) is a self-adaptive method, which has been widely applied to extract early fault signals from bearings. However, mode mixing occurs during the decomposition process. Moreover, in processing signals with strong noise, false frequency components can be generated by variational mode decomposition (VMD). To address these problems, a weak fault extraction method based on VMD is proposed for rolling bearings. This method regards LMD and the combination production function (CPF) as prefilters for VMD. First, LMD is used for denoising the original signal, and then the CPF components that contain the fault information are combined into a new signal. Second, this method determines the decomposition level K of the VMD from the spectral peaks of the recombined signal. Finally, this method decomposes the recombined signal using the VMD. The main contributions of the proposed method are (i) the CPF method is employed for adaptively de-noising, and the power of the fault feature can be improved; (ii) the decomposition level K of the VMD can be determined adaptively. After processing a simulated signal, fault information of the gears and rolling elements is successfully extracted, thereby demonstrating the feasibility of the presented method. Moreover, the feasibility of the proposed method is further demonstrated in a comparison of results with those obtained from the MOMEDA (Multipoint Optimal Minimum Entropy Deconvolution Adjusted) algorithm.

18.
J Am Chem Soc ; 140(37): 11618-11622, 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30176719

RESUMO

A C3-symmetric benzotrithiophene tricarbaldehyde (BTT) is synthesized for the first time with a facile method, which is used to construct BTT-based covalent organic frameworks (COFs) with different pore sizes. Meanwhile, the structure transformations of the COFs under high-temperature ionothermal condition are studied systematically, and the relationships between the regularly changed structures of the further-cross-linked COFs and their supercapacitor performances are investigated. It turns out that dealing with COFs of designated structures under ionothermal condition is a great method to build highly conductive structure-controllable materials for electrochemical applications.

19.
Bioresour Technol ; 264: 382-386, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29983227

RESUMO

An efficient emulsion microreactor was constructed for selective conversion of lignosulfonate via hydrogen transfer reaction based on the self-surfactivity of this natural aromatic polymer. Industrial Raney Ni and isopropanol were used as catalyst and hydrogen donor, respectively. The results showed that the emulsion microreactor has a remarkable process intensification effect on the lignosulfonate depolymerization. Under mild condition of 473 K for 2.0 h, 116.1 mg g-1 of volatile phenolic monomer can be obtained, which is twice of that from other investigated processes without emulsion of this work. In particular, 39.3 mg g-1 of which is composed of 4-ethyl guaiacol, an important and versatile chemical currently from petrochemical industry. Furthermore, the solvent separates to two phases automatically after reaction due to the consumption of lignosulfonate, which makes handy products enrichment and separation. Additionally, the emulsion microreactor is significantly affected by hydrogen donor and is efficient for other lignin sources as well.


Assuntos
Reatores Biológicos , Lignina/análogos & derivados , Catálise , Hidrogênio , Lignina/química , Polimerização
20.
ACS Appl Mater Interfaces ; 10(27): 23112-23121, 2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29923708

RESUMO

Direct dehydrogenation of isobutane to isobutene has drawn extensive attention for synthesizing various chemicals. The Mo-based catalysts hold promise as an alternative to the toxic CrO x- and scarce Pt-based catalysts. However, the low activity and rapid deactivation of the Mo-based catalysts greatly hinder their practical applications. Herein, we demonstrate a feasible approach toward the development of efficient and non-noble metal dehydrogenation catalysts based on Mo-C T hybrid nanowires calcined at different temperatures. In particular, the optimal Mo-C700 catalyst exhibits isobutane consumption rate of 3.9 mmol g-1 h-1 and isobutene selectivity of 73% with production rate of 2.8 mmol g-1 h-1. The catalyst maintained 90% of its initial activity after 50 h of reaction. Extensive characterizations reveal that such prominent performance is well correlated with the adsorption abilities of isobutane and isobutene and the formation of η-MoC species. In contrast, the generation of ß-Mo2C crystalline phase during long-term reaction causes minor decline in activity. Compared to MoO2 and ß-Mo2C, η-MoC plays a role more likely in suppressing the cracking reaction. This work demonstrates a feasible approach toward the development of efficient and non-noble metal dehydrogenation catalysts.

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