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1.
Plant Cell ; 35(11): 4133-4154, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37542517

RESUMO

Phytohormones play indispensable roles in plant growth and development. However, the molecular mechanisms underlying phytohormone-mediated regulation of fiber secondary cell wall (SCW) formation in cotton (Gossypium hirsutum) remain largely underexplored. Here, we provide mechanistic evidence for functional interplay between the APETALA2/ethylene response factor (AP2/ERF) transcription factor GhERF108 and auxin response factors GhARF7-1 and GhARF7-2 in dictating the ethylene-auxin signaling crosstalk that regulates fiber SCW biosynthesis. Specifically, in vitro cotton ovule culture revealed that ethylene and auxin promote fiber SCW deposition. GhERF108 RNA interference (RNAi) cotton displayed remarkably reduced cell wall thickness compared with controls. GhERF108 interacted with GhARF7-1 and GhARF7-2 to enhance the activation of the MYB transcription factor gene GhMYBL1 (MYB domain-like protein 1) in fibers. GhARF7-1 and GhARF7-2 respond to auxin signals that promote fiber SCW thickening. GhMYBL1 RNAi and GhARF7-1 and GhARF7-2 virus-induced gene silencing (VIGS) cotton displayed similar defects in fiber SCW formation as GhERF108 RNAi cotton. Moreover, the ethylene and auxin responses were reduced in GhMYBL1 RNAi plants. GhMYBL1 directly binds to the promoters of GhCesA4-1, GhCesA4-2, and GhCesA8-1 and activates their expression to promote cellulose biosynthesis, thereby boosting fiber SCW formation. Collectively, our findings demonstrate that the collaboration between GhERF108 and GhARF7-1 or GhARF7-2 establishes ethylene-auxin signaling crosstalk to activate GhMYBL1, ultimately leading to the activation of fiber SCW biosynthesis.


Assuntos
Fibra de Algodão , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ácidos Indolacéticos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Gossypium/genética , Gossypium/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Etilenos/metabolismo , Parede Celular/metabolismo
2.
BMC Nephrol ; 25(1): 174, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773467

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is a common postoperative complication in patients who undergo radical nephrectomy for renal tumours. However, the factors influencing long-term renal function require further investigation. OBJECTIVE: This study was designed to investigate the trends in renal function changes and risk factors for renal function deterioration in renal tumour patients after radical nephrectomy. METHODS: We monitored changes in renal function before and after surgery for 3 years. The progression of renal function was determined by the progression and degradation of CKD stages. Univariate and multivariate logistic regression analyses were used to analyse the causes of renal function progression. RESULTS: We analysed the data of 329 patients with renal tumours who underwent radical nephrectomies between January 2013 and December 2018. In this study, 43.7% of patients had postoperative acute kidney injury (AKI), and 48.3% had CKD at advanced stages. Further research revealed that patients' renal function stabilized 3 months after surgery. Additionally, renal function changes during these 3 months have a substantial impact on the progression of long-term renal function changes in patients. CONCLUSION: AKI may be an indicator of short-term postoperative changes in renal function. Renal function tests should be performed in patients with AKI after radical nephrectomy to monitor the progression of functional impairment, particularly within the first 3 months after radical nephrectomy.


Assuntos
Injúria Renal Aguda , Neoplasias Renais , Nefrectomia , Complicações Pós-Operatórias , Insuficiência Renal Crônica , Humanos , Nefrectomia/efeitos adversos , Masculino , Neoplasias Renais/cirurgia , Feminino , Pessoa de Meia-Idade , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/fisiopatologia , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Idoso , Progressão da Doença , Fatores de Risco , Taxa de Filtração Glomerular , Rim/fisiopatologia , Estudos Retrospectivos , Testes de Função Renal
3.
Proc Natl Acad Sci U S A ; 118(35)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34429362

RESUMO

The popularly reported energy storage mechanisms of potassium-ion batteries (PIBs) are based on alloy-, de-intercalation-, and conversion-type processes, which inevitably lead to structural damage of the electrodes caused by intercalation/de-intercalation of K+ with a relatively large radius, which is accompanied by poor cycle stabilities. Here, we report the exploration of robust high-temperature PIBs enabled by a carboxyl functional group energy storage mechanism, which is based on an example of p-phthalic acid (PTA) with two carboxyl functional groups as the redox centers. In such a case, the intercalation/de-intercalation of K+ can be performed via surface reactions with relieved volume change, thus favoring excellent cycle stability for PIBs against high temperatures. As proof of concept, at the fixed working temperature of 62.5 °C, the initial discharge and charge specific capacities of the PTA electrode are ∼660 and 165 mA⋅h⋅g-1, respectively, at a current density of 100 mA⋅g-1, with 86% specific capacity retention after 160 cycles. Meanwhile, it delivers 81.5% specific capacity retention after 390 cycles under a high current density of 500 mA⋅g-1 The cycle stabilities achieved under both low and high current densities are the best among those of high-temperature PIBs reported previously.

4.
Proc Natl Acad Sci U S A ; 118(21)2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34011610

RESUMO

In terms of ideal future energy storage systems, besides the always-pursued energy/power characteristics, long-term stability is crucial for their practical application. Here, we report a facile and sustainable strategy for the scalable fabrication of carbon aerogels with three-dimensional interconnected nanofiber networks and rationally designed hierarchical porous structures, which are based on the carbonization of bacterial cellulose assisted by the soft template of Zn-1,3,5-benzenetricarboxylic acid. As binder-free electrodes, they deliver a fundamentally enhanced specific capacitance of 352 F ⋅ g-1 at 1 A ⋅ g-1 in a wide potential window (1.2 V, 6 M KOH) in comparison with those of bacterial cellulose-derived carbons (178 F ⋅ g-1) and most activated carbons (usually lower than 250 F ⋅ g-1). The as-assembled supercapacitors exhibit an ultrahigh capacitance of 297 F ⋅ g-1 at 1 A ⋅ g-1, remarkable energy density (14.83 Wh ⋅ kg-1 at 0.60 kW ⋅ kg-1), and extremely high stability, with 100% capacitance retention for up to 65,000 cycles at 6 A ⋅ g-1, representing their superior energy storage performance when compared with that of state-of-the-art supercapacitors of commercial activated carbons and biomass-derived analogs.

5.
BMC Genomics ; 24(1): 502, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37648999

RESUMO

BACKGROUND: As an important reproductive hormone, melatonin plays an important role in regulating the reproductive activities of sheep and other mammals. Hu sheep is a breed favoring for meat, with prolific traits. In order to explore the relationship between melatonin and reproductive function of Hu sheep, 7,694,759 SNPs were screened out through the whole genome sequencing analysis from high and low melatonin production Hu sheep. RESULTS: A total of 68,673 SNPs, involving in 1126 genes, were identified by ED association analysis. Correlation analysis of SNPs of AANAT/ASMT gene and MTNR1A/MTNR1B gene were carried out. The melatonin level of CG genotype 7,981,372 of AANAT, GA genotype 7,981,866 of ASMT and GG genotype 17,355,171 of MTNR1A were higher than the average melatonin level of 1.64 ng/mL. High melatonin Hu sheep appear to have better multiple reproductive performance. CONCLUSIONS: By using different methods, three SNPs which are associated with high melatonin production trait have been identified in Hu sheep. These 3 SNPs are located in melatonin synthetase AANAT/ASMT and receptor MTNR1A, respectively. Considering the positive association between melatonin production and reproductive performance in ruminants, these three SNPs can be served as the potential molecular markers for breading Hu sheep with the desirable reproductive traits.


Assuntos
Melatonina , Ovinos/genética , Animais , Melatonina/genética , Polimorfismo de Nucleotídeo Único , Fenótipo , Genótipo , Pão , Mamíferos
6.
Int J Colorectal Dis ; 38(1): 82, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36971914

RESUMO

PURPOSE: There is not enough information to position medications for the treatment of Crohn's disease (CD). Therefore, using a network meta-analysis and systematic review, we evaluated the efficacy and safety of combination therapy and infliximab (IFX) monotherapy in CD patients. METHODS: We identified randomized controlled trials (RCTs) in CD patients who were given IFX-containing combination therapy versus IFX monotherapy. Induction and maintenance of clinical remission were the efficacy outcomes, while adverse events were the safety outcomes. The surface under cumulative ranking (SUCRA) probabilities was used to assess ranking in the network meta-analysis. RESULTS: In total, 15 RCTs with 1586 CD patients were included in this study. There was no statistical difference between different combination therapies in induction and maintenance of remission. In terms of inducing clinical remission, IFX + EN (SUCRA: 0.91) ranked highest; in terms of maintaining clinical remission, IFX + AZA (SUCRA: 0.85) ranked highest. There was no treatment that was significantly safer than the others. In terms of any adverse events, serious adverse events, serious infections, and infusion/injection-site reactions, IFX + AZA (SUCRA: 0.36, 0.12, 0.19, and 0.24) was ranked lowest for all risks; while IFX + MTX (SUCRA: 0.34, 0.06, 0.13, 0.08, 0.34, and 0.08) was rated lowest for risk of abdominal pain, arthralgia, headache, nausea, pyrexia, and upper respiratory tract infection. CONCLUSION: Indirect comparisons suggested that efficacy and safety of different combination treatments are comparable in CD patients. For maintenance therapies, IFX + AZA was ranked highest for clinical remission and lowest for adverse events. Further head-to-head trials are required.


Assuntos
Doença de Crohn , Humanos , Infliximab/efeitos adversos , Doença de Crohn/tratamento farmacológico , Imunossupressores/uso terapêutico , Metanálise em Rede , Indução de Remissão
7.
BMC Urol ; 23(1): 52, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36997995

RESUMO

INTRODUCTION: Neobladder urolithiasis is a rare but important delaying complication of orthotopic urinary diversion. We report a case of Hem-o-Lok (HOLC) migration into the neobladder with giant stone formation after orthotopic neobladder cystectomy. CASE REPORT: We report a case of a 57-year-old man with frequent urination and occasional discharge of stones 3 years after a laparoscopic orthotopic neobladder cystectomy. Computed tomography revealed a large round 3.5 cm calculus. An endoscopic neocystolitholapaxy was performed, and a Hem-o-Lok was found in the center of the stone. CONCLUSION: We described the case presentation, treatment and analysis of etiology of stone formation to avoid such complication.


Assuntos
Cálculos , Laparoscopia , Derivação Urinária , Masculino , Humanos , Pessoa de Meia-Idade , Cistectomia , Instrumentos Cirúrgicos
8.
Heart Surg Forum ; 26(3): E271-E276, 2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37401434

RESUMO

BACKGROUND: To analyze the clinical effect of debranching thoracic endovascular aortic repair combined with ascending aortic banding. METHODS: The clinical data of patients who underwent a debranching thoracic endovascular aortic repair combined with ascending aortic banding at Anzhen Hospital (Beijing, China) between January 2019 and December 2021 were reviewed to evaluate the occurrence and outcomes of postoperative complications. RESULTS: A total of 30 patients underwent a debranching thoracic endovascular aortic repair combined with ascending aortic banding. There were 28 male patients (93.3%) with an average age of 59.9 ± 11.8 years. Twenty-five patients underwent simultaneous surgery and five patients had staged surgery. Postoperatively, two patients developed complete paraplegia (6.7%), three patients developed incomplete paraplegia (10%), two patients developed cerebral infarction (6.7%), and one patient developed femoral artery thromboembolism (3.3%). No patient died during the perioperative period, and one patient (3.3%) died during the follow-up period. None of the patients underwent retrograde type A aortic dissection during the perioperative and postoperative follow-up periods. CONCLUSIONS: Banding the ascending aorta with a vascular graft to restrict its movement and to serve as the proximal anchoring area of the stent graft can reduce the risk of retrograde type A aortic dissection.


Assuntos
Aneurisma da Aorta Torácica , Correção Endovascular de Aneurisma , Correção Endovascular de Aneurisma/métodos , Humanos , Estudos Retrospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Dissecção Aórtica/cirurgia , Dissecção da Aorta Ascendente , Stents , Prótese Vascular , Resultado do Tratamento , Complicações Pós-Operatórias , Aneurisma da Aorta Torácica/cirurgia
9.
J Cardiovasc Pharmacol ; 80(2): 251-260, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35416804

RESUMO

ABSTRACT: Sodium ferulate (SF) is the sodium salt of ferulic acid, which is one of the effective components of Angelica sinensis and Lignsticum chuanxiong , and plays an important role in protecting the cardiovascular system. In this study, myocardial hypertrophy was induced by angiotensin II 0.1 µmol/L in neonatal Sprague-Dawley rat ventricular myocytes. Nine groups were designed, that is, normal, normal administration, model, L-arginine (L-arg 1000 µmol/L), SF (50, 100, 200 µmol/L) group, and N G -nitro-L-arg-methyl ester 1500 µmol/L combined with SF 200 µmol/L or L-arg 1000 µmol/L group, respectively. Cardiomyocyte hypertrophy was confirmed by observing histological changes and measurements of cell diameter, protein content and atrial natriuretic factor, and ß-myosin heavy chain levels of the cells. Notably, SF could inhibit significantly myocardial hypertrophy of neonatal rat cardiomyocytes in a concentration-dependent manner without producing cytotoxicity, and the levels of nitric oxide, NO synthase (NOS), endothelial NOS, and cyclic guanosine monophosphate were increased, but the level of cyclic adenosine monophosphate was decreased in cardiomyocytes. Simultaneously, levels of protein kinase C beta, Raf-1, and extracellular regulated protein kinase 1/2 (ERK1/2) were downregulated, whereas levels of mitogen-activated protein kinase phosphatase-1 were significantly upregulated. All the beneficial effects of SF were blunted by N G -nitro-L-arg-methyl ester. Overall, these findings reveal that SF can inhibit angiotensin II-induced myocardial hypertrophy of neonatal rat cardiomyocytes, which is closely related to activation of endothelial NOS/NO/cyclic guanosine monophosphate, and inhibition of protein kinase C and mitogen-activated protein kinase signaling pathways.


Assuntos
Angiotensina II , Óxido Nítrico Sintase Tipo III , Angiotensina II/metabolismo , Animais , Cardiomegalia/induzido quimicamente , Cardiomegalia/tratamento farmacológico , Cardiomegalia/prevenção & controle , Ácidos Cumáricos , GMP Cíclico/metabolismo , Ésteres , Guanosina Monofosfato/metabolismo , Guanosina Monofosfato/farmacologia , Miócitos Cardíacos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
10.
Br J Nutr ; 127(12): 1761-1773, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-34321122

RESUMO

The present study evaluated effects of dietary supplementation with tryptophan (Trp) on muscle growth, protein synthesis and antioxidant capacity in hybrid catfish Pelteobagrus vachelli♀ × Leiocassis longirostris♂. Fish were fed six different diets containing 2·6 (control), 3·1, 3·7, 4·2, 4·7 and 5·6 g Trp/kg diet for 56 d, respectively. Results showed that dietary Trp significantly (1) improved muscle protein content, fibre density and frequency of fibre diameter; (2) up-regulated the mRNA levels of PCNA, myf5, MyoD1, MyoG, MRF4, IGF-I, IGF-II, IGF-IR, PIK3Ca, TOR, 4EBP1 and S6K1; (3) increased phosphorylation levels of AKT, TOR and S6K1; (4) decreased contents of MDA and PC, and increased activities of CAT, GST, GR, ASA and AHR; (5) up-regulated mRNA levels of CuZnSOD, CAT, GST, GPx, GCLC and Nrf2, and decreased Keap1 mRNA level; (6) increased nuclear Nrf2 protein level and the intranuclear antioxidant response element-binding ability, and reduced Keap1 protein level. These results indicated that dietary Trp improved muscle growth, protein synthesis as well as antioxidant capacity, which might be partly related to myogenic regulatory factors, IGF/PIK3Ca/AKT/TOR and Keap1/Nrf2 signalling pathways. Finally, based on the quadratic regression analysis of muscle protein and MDA contents, the optimal Trp requirements of hybrid catfish (21·82-39·64 g) were estimated to be 3·94 and 3·93 g Trp/kg diet (9·57 and 9·54 g/kg of dietary protein), respectively.


Assuntos
Antioxidantes , Peixes-Gato , Animais , Antioxidantes/metabolismo , Suplementos Nutricionais/análise , Triptofano , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Peixes-Gato/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Dieta , Músculos/metabolismo , Proteínas Musculares/metabolismo , RNA Mensageiro , Ração Animal/análise , Proteínas de Peixes/genética
11.
J Card Surg ; 37(10): 3426-3427, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35916149

RESUMO

A stented elephant trunk graft entrapped in the false lumen during Sun's procedure (total arch replacement combined with stented elephant trunk implantation) is a serious complication with an extremely high mortality rate. This article describes a case of a patient who was successfully saved with the use of thoracic endovascular aortic repair.


Assuntos
Aneurisma da Aorta Torácica , Dissecção Aórtica , Implante de Prótese Vascular , Procedimentos Endovasculares , Dissecção Aórtica/cirurgia , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Prótese Vascular , Implante de Prótese Vascular/métodos , Procedimentos Endovasculares/métodos , Humanos , Stents , Resultado do Tratamento
12.
Br J Nutr ; 123(2): 121-134, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31637992

RESUMO

The experiment was conducted to investigate the effects of dietary threonine (Thr) on growth performance and muscle growth, protein synthesis and antioxidant-related signalling pathways of hybrid catfish Pelteobagrus vachelli♀ × Leiocassis longirostris♂. A total of 1200 fish (14·19 (se 0·13) g) were randomly distributed into six groups with four replicates each, fed six diets with graded level of Thr (9·5, 11·5, 13·5, 15·4, 17·4 and 19·3 g/kg diets) for 56 d. Results showed (P < 0·05) that dietary Thr (1) increased percentage weight gain, specific growth rate, feed efficiency and protein efficiency ratio; (2) up-regulated growth hormone (GH), insulin-like growth factor 1 (IGF-1), proliferating cell nuclear antigen, myogenic regulation factors (MyoD, Myf5, MyoG and Mrf4) and myosin heavy chain (MyHC) mRNA levels; (3) increased muscle protein content via regulating the protein kinase B/target of rapamycin signalling pathway and (4) decreased malondialdehyde and protein carbonyl contents, increased catalase, glutathione-S-transferase, glutathione reductase and GSH activities, up-regulated mRNA levels of antioxidant enzymes related to NFE2-related factor 2 and γ-glutamylcysteine ligase catalytic subunit. These results suggest that Thr has a potential role to improve muscle growth and protein synthesis, which might be due to the regulation of GH-IGF system, muscle growth-related gene, antioxidative capacity and protein synthesis-related signalling pathways. Based on the quadratic regression analysis of specific growth rate, the Thr requirement of hybrid catfish (14·19-25·77 g) was estimated to be 13·77 g/kg of the diet (33·40 g/kg of dietary protein).


Assuntos
Ração Animal/análise , Peixes-Gato/crescimento & desenvolvimento , Peixes-Gato/metabolismo , Músculos/efeitos dos fármacos , Treonina/administração & dosagem , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Peixes-Gato/genética , Quimera/crescimento & desenvolvimento , Quimera/metabolismo , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Músculos/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
13.
J Am Soc Nephrol ; 30(10): 1910-1924, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31416818

RESUMO

BACKGROUND: Mutations in the transient receptor potential channel 6 (TRPC6) gene are associated with an inherited form of FSGS. Despite widespread expression, patients with TRPC6 mutations do not present with any other pathologic phenotype, suggesting that this protein has a unique yet unidentified role within the target cell for FSGS, the kidney podocyte. METHODS: We generated a stable TRPC6 knockout podocyte cell line from TRPC6 knockout mice. These cells were engineered to express wild-type TRPC6, a dominant negative TRPC6 mutation, or either of two disease-causing mutations of TRPC6, G109S or K874*. We extensively characterized these cells using motility, detachment, and calpain activity assays; immunofluorescence; confocal or total internal reflection fluorescence microscopy; and western blotting. RESULTS: Compared with wild-type cells, TRPC6-/- podocytes are less motile and more adhesive, with an altered actin cytoskeleton. We found that TRPC6 binds to ERK1/2 and the actin regulatory proteins, caldesmon (a calmodulin- and actin-binding protein) and calpain 1 and 2 (calcium-dependent cysteine proteases that control the podocyte cytoskeleton, cell adhesion, and motility via cleavage of paxillin, focal adhesion kinase, and talin). Knockdown or expression of the truncated K874* mutation (but not expression of the gain-of-function G019S mutation or dominant negative mutant of TRPC6) results in the mislocalization of calpain 1 and 2 and significant downregulation of calpain activity; this leads to altered podocyte cytoskeleton, motility, and adhesion-characteristics of TRPC6-/- podocytes. CONCLUSIONS: Our data demonstrate that independent of TRPC6 channel activity, the physical interaction between TRPC6 and calpain in the podocyte is important for cell motility and detachment and demonstrates a scaffolding role of the TRPC6 protein in disease.


Assuntos
Calpaína/fisiologia , Adesão Celular , Movimento Celular , Citoesqueleto/fisiologia , Podócitos/fisiologia , Podócitos/ultraestrutura , Canal de Cátion TRPC6/fisiologia , Animais , Camundongos , Camundongos Knockout
14.
Toxicol Appl Pharmacol ; 379: 114615, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-31175882

RESUMO

Mercury (Hg) is generally considered as a toxic metal; yet the biological outcomes of Hg-containing compounds are highly dependent upon their chemical forms. We hypothesize that mercury sulfide (HgS) is different from HgCl2 and methylmercury (MeHg) in producing intestinal Hg absorption and disruption of gut microbiome. To test this hypothesis, mice were given orally with HgS (α-HgS, 30 mg/kg), Zuotai (ß-HgS, 30 mg/kg), HgCl2 (33.6 mg/kg, equivalent Hg as HgS), or MeHg (3.1 mg/kg, 1/10 Hg as HgS) for 7 days. Accumulation of Hg in the duodenum and ileum after HgCl2 (30-40 fold) and MeHg (10-15 fold) was higher than HgS and Zuotai (~2-fold). HgCl2 and MeHg decreased intestinal intake peptide transporter-1 and Ost-ß, and increased ileal bile acid binding protein and equilibrative nucleoside transporter-1. The efflux transporters ATP-binding cassette sub-family C member-4 (Abcc4), Abcg2, Abcg5/8, and Abcb1b were increased by HgCl2 and to a lesser extent by MeHg, while HgS and Zuotai had minimal effects. Bacterial DNA was extracted and subjected to 16S rDNA sequencing. Operational taxonomic unit (OTU) results showed that among the 10 phyla, HgS increased Firmicutes, Proteobacteria, while HgCl2 increased Bacteroidetes, Cyanobacteria and decreased Firmicutes; among the 79 families, HgS increased Rikenellaceae, Lactobacillaceae, Helicobacteraceae, and decreased Prevotellaceae, while HgCl2 increased Odoribacteraceae, Porphyromonadaceae, and decreased Lactobacillaceae; among the 232 genus/species, HgS and Zuotai affected gut microbiome quite differently from HgCl2 and MeHg. qPCR analysis with 16S rRNA confirmed sequencing results. Thus, chemical forms of mercury are a major determinant for intestinal Hg accumulation, alterations in transporters and disruption of microbiome.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Absorção Intestinal/efeitos dos fármacos , Cloreto de Mercúrio/toxicidade , Compostos de Mercúrio/farmacocinética , Animais , Duodeno/metabolismo , Microbioma Gastrointestinal/genética , Íleo/metabolismo , Íleo/patologia , Masculino , Proteínas de Membrana Transportadoras/efeitos dos fármacos , Proteínas de Membrana Transportadoras/metabolismo , Compostos de Mercúrio/toxicidade , Camundongos , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase em Tempo Real
15.
Liver Int ; 39(3): 427-439, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30079536

RESUMO

Oleanolic acid (OA) is a triterpenoid that exists widely in fruits, vegetables and medicinal herbs. OA is included in some dietary supplements and is used as a complementary and alternative medicine (CAM) in China, India, Asia, the USA and European countries. OA is effective in protecting against various hepatotoxicants, and one of the protective mechanisms is reprogramming the liver to activate the nuclear factor erythroid 2-related factor 2 (Nrf2). OA derivatives, such as CDDO-Im and CDDO-Me, are even more potent Nrf2 activators. OA has recently been shown to also activate the Takeda G-protein-coupled receptor (TGR5). However, whereas a low dose of OA is hepatoprotective, higher doses and long-term use of OA can produce liver injury, characterized by cholestasis. This paradoxical hepatotoxic effect occurs not only for OA, but also for other OA-type triterpenoids. Dose and length of time of OA exposure differentiate the ability of OA to produce hepatoprotection vs hepatotoxicity. Hepatotoxicity produced by herbs is increasingly recognized and is of global concern. Given the appealing nature of OA in dietary supplements and its use as an alternative medicine around the world, as well as the development of OA derivatives (CDDO-Im and CDDO-Me) as therapeutics, it is important to understand not only that they program the liver to protect against hepatotoxic chemicals, but also how they produce hepatotoxicity.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Fígado/efeitos dos fármacos , Ácido Oleanólico/efeitos adversos , Substâncias Protetoras/efeitos adversos , Animais , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Citoproteção , Relação Dose-Resposta a Droga , Humanos , Fígado/metabolismo , Fígado/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Medição de Risco , Fatores de Risco , Transdução de Sinais , Fatores de Tempo
16.
Nanotechnology ; 30(47): 475708, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31507271

RESUMO

The excellent mechanical properties of single- and few-layer graphene have been well-quantified and evidenced by computational methods and local indentation measurements. However, there are less experimental reports on the in-plane mechanical properties of multilayer graphene sheets, despite many practical applications in flexible electronic and energy devices (e.g. graphene flexible electronic display, battery, and storage devices) are actually based on these thicker nanosheets. Here, in-plane fracture behaviors of multilayer graphene nanosheets with thicknesses between ∼10 and 300 nm (∼10-1000 layers) are characterized and quantified by in situ scanning electron microscopy and transmission electron microscopy under tensile loading. We found that, generally, the fracture strengths of graphene nanosheets decrease as the thickness (or layers) increases; however, the fracture strain of thinner graphene sheets is less than that of thicker sheets. The fracture process of the thicker nanosheets includes the initial flattened stage, the stable elastic stage, and the rapid fracture with brittle characteristics, while the thinner nanosheets show obvious delamination between the atomic layers at fracture. This work provides critical experimental insights into the tensile fracture behavior of multilayer two-dimensional materials and a better understanding on their realistic mechanical performance for potential flexible device and composite applications.

17.
Int Heart J ; 60(5): 1196-1200, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31484862

RESUMO

Malignant arrhythmia is a fast cardiac arrhythmia that can lead to a hemodynamic abnormality within a short time, most of which is ventricular tachycardia or ventricular fibrillation (VF), which should be managed in time. Both organic and nonorganic cardiac diseases have the potential to cause malignant arrhythmia. We report a noteworthy case of malignant arrhythmia in a teenager during exercise. Transthoracic echocardiography, cardiac magnetic resonance (CMR), electrophysiological study, magnetic resonance imaging of the brain, electroencephalography, chest X-ray, and blood tests were all normal. Twelve-lead electrocardiography showed incomplete right bundle branch block (IRBBB). Two heterozygous missense variants of the desmocollin-2 gene (DSC2, c.G2446A/p.V816M) and desmoplakin gene (DSP, c.G3620A/p.R1207K) were detected in the peripheral blood of this teenager and his father by genetic testing, which encoded a desmosomal protein that was related to arrhythmogenic right ventricular cardiomyopathy (ARVC). In these two rare variants, DSC2 V816M has been reported but uncertain significance, whereas DSP R1207K is never reported. Therefore, the two site variants in DSC2 and DSP genes are likely to become a new research focus for diagnosis and treatment of ARVC in the future. Meanwhile, this report emphasizes that, in addition to a standard set of laboratory tests and examinations, genetic testing may be useful for analyzing the causes of malignant arrhythmia.


Assuntos
Arritmias Cardíacas/etiologia , Bloqueio de Ramo/genética , Desmocolinas/genética , Eletrocardiografia/métodos , Predisposição Genética para Doença , Adolescente , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/genética , Bloqueio de Ramo/complicações , Bloqueio de Ramo/diagnóstico , Ecocardiografia/métodos , Testes Genéticos/métodos , Humanos , Masculino , Linhagem , Prognóstico , Doenças Raras , Medição de Risco , Índice de Gravidade de Doença
18.
Fish Physiol Biochem ; 45(5): 1627-1647, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31161532

RESUMO

The 56-day feeding trial was carried out to investigate the effects of dietary tryptophan (Trp) on growth performance, digestive and absorptive enzyme activities, intestinal antioxidant capacity, and appetite and GH-IGF axis-related genes expression of hybrid catfish (Pelteobagrus vachelli♀ × Leiocassis longirostris♂). A total of 864 hybrid catfish (21.82 ± 0.14 g) were fed six different experimental diets containing graded levels of Trp at 2.6, 3.1, 3.7, 4.2, 4.7, and 5.6 g kg-1 diet. The results indicated that dietary Trp increased (P < 0.05) (1) final body weight, percent weight gain, specific growth rate, feed intake, feed efficiency, and protein efficiency ratio; (2) fish body protein, lipid and ash contents, protein, and ash production values; (3) stomach weight, stomach somatic index, liver weight, intestinal weight, length and somatic index, and relative gut length; and (4) activities of pepsin in the stomach; trypsin, chymotrypsin, lipase, and amylase in the pancreas and intestine; and γ-glutamyl transpeptidase, Na+, K+-ATPase, and alkaline phosphatase in the intestine. Dietary Trp decreased malondialdehyde content, increased antioxidant enzyme activities and glutathione content, but downregulated Keap1 mRNA expression, and upregulated the expression of NPY, ghrelin, GH, GHR, IGF1, IGF2, IGF1R, PIK3Ca, AKT1, TOR, 4EBP1, and S6K1 genes. These results indicated that Trp improved hybrid catfish growth performance, digestive and absorptive ability, antioxidant status, and appetite and GH-IGF axis-related gene expression. Based on the quadratic regression analysis of PWG, SGR, and FI, the dietary Trp requirement of hybrid catfish (21.82-39.64 g) was recommended between 3.96 and 4.08 g kg-1 diet (9.4-9.7 g kg-1 of dietary protein).


Assuntos
Apetite/efeitos dos fármacos , Peixes-Gato/genética , Peixes-Gato/fisiologia , Cruzamentos Genéticos , Intestinos/efeitos dos fármacos , Triptofano/farmacologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Antioxidantes/metabolismo , Dieta/veterinária , Digestão/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônio do Crescimento/genética , Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/metabolismo , Intestinos/enzimologia , Intestinos/fisiologia , Triptofano/administração & dosagem
19.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(6): 573-579, 2019 Jun.
Artigo em Zh | MEDLINE | ID: mdl-31208512

RESUMO

OBJECTIVE: To study the clinical value of serum neuroglobin in evaluating hypoglycemic brain injury in neonates. METHODS: A total of 100 neonates with hypoglycemia were enrolled as subjects. According to amplitude-integrated EEG (aEEG) findings and/or clinical manifestations, they were divided into symptomatic hypoglycemic brain injury group (n=22), asymptomatic hypoglycemic brain injury group (n=37) and hypoglycemic non-brain injury group (n=41). The three groups were compared in terms of blood glucose, duration of hypoglycemia, levels of neuroglobin and neuron-specific enolase (NSE), and modified aEEG score. The correlation of neuroglobin with NSE and modified aEEG score was analyzed. The receiver operating characteristic (ROC) curve was plotted. RESULTS: Compared with the asymptomatic hypoglycemic brain injury and hypoglycemic non-brain injury groups, the symptomatic hypoglycemic brain injury group had significantly lower blood glucose and modified aEEG score, significantly higher neuroglobin and NSE levels, and a significantly longer duration of hypoglycemia (P<0.05). Compared with the hypoglycemic non-brain injury group, the asymptomatic hypoglycemic brain injury group had significantly lower blood glucose and modified aEEG score, significantly higher neuroglobin and NSE levels, and a significantly longer duration of hypoglycemia (P<0.05). Neuroglobin was positively correlated with NSE and duration of hypoglycemia (r=0.922 and 0.929 respectively; P<0.05) and negatively correlated with blood glucose and modified aEEG score (r=-0.849 and -0.968 respectively; P<0.05). The areas under the ROC curve of neuroglobin, NSE and modified aEEG score were 0.894, 0.890 and 0.941 respectively, and neuroglobin had a sensitivity of 80.8% and a specificity of 95.8% at the optimal cut-off value of 108 mg/L. CONCLUSIONS: Like NSE and modified aEEG score, serum neuroglobin can also be used as a specific indicator for the assessment of brain injury in neonates with hypoglycemia and has a certain value in clinical practice.


Assuntos
Lesões Encefálicas , Neuroglobina/sangue , Eletroencefalografia , Humanos , Hipoglicemiantes , Recém-Nascido , Fosfopiruvato Hidratase
20.
Small ; 14(20): e1704085, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29665233

RESUMO

As the critical feature sizes of integrated circuits approaching sub-10 nm, ultrathin gold nanowires (diameter <10 nm) have emerged as one of the most promising candidates for next-generation interconnects in nanoelectronics. Also due to their ultrasmall dimensions, however, the structures and morphologies of ultrathin gold nanowires are more prone to be damaged during practical services, for example, Rayleigh instability can significantly alter their morphologies upon Joule heating, hindering their applications as interconnects. Here, it is shown that upon mechanical perturbations, predamaged, nonuniform ultrathin gold nanowires can quickly recover into uniform diameters and restore their smooth surfaces, via a simple mechanically assisted self-healing process. By examining the local self-healing process through in situ high-resolution transmission electron microscopy, the underlying mechanism is believed to be associated with surface atomic diffusion as evidenced by molecular dynamics simulations. In addition, mechanical manipulation can assist the atoms to overcome the diffusion barriers, as suggested by ab initio calculations, to activate more surface adatoms to diffuse and consequently speed up the self-healing process. This result can provide a facile method to repair ultrathin metallic nanowires directly in functional devices, and quickly restore their microstructures and morphologies by simple global mechanical perturbations.

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