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1.
Am J Pathol ; 194(6): 879-893, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38417698

RESUMO

Cholestatic liver diseases encompass a range of organic damages, metabolic disorders, and dysfunctions within the hepatobiliary system, arising from various pathogenic causes. These factors contribute to disruptions in bile production, secretion, and excretion. Cholestatic liver diseases can be classified into intrahepatic and extrahepatic cholestasis, according to the location of occurrence. The etiology of cholestatic liver diseases is complex, and includes drugs, poisons, viruses, parasites, bacteria, autoimmune responses, tumors, and genetic metabolism. The pathogenesis of cholelstatic liver disease is not completely clarified, and effective therapy is lacking. Clarifying its mechanism to find more effective therapeutic targets and drugs is an unmet need. Increasing evidence demonstrates that miRNA and long noncoding RNA are involved in the progression of cholestatic liver diseases. This review provides a comprehensive summary of the research progress on the roles of miRNA and long noncoding RNA in cholestatic liver diseases. The aim of the review is to enhance the understanding of their potential diagnostic, therapeutic, and prognostic value for patients with cholestasis.


Assuntos
Colestase , MicroRNAs , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Colestase/genética , Colestase/metabolismo , Colestase/patologia , Animais , Hepatopatias/genética , Hepatopatias/metabolismo , Hepatopatias/patologia
2.
Br J Haematol ; 202(4): 856-865, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37365147

RESUMO

We aimed to identify the efficacy of haploidentical related donor (HID) haematopoietic stem cell transplantation (HSCT) in adolescent and young adults (AYAs) with acute myeloid leukaemia (AML) in a large cohort. Consecutive AML AYAs (15-39 years old, n = 599) receiving HID HSCT in complete remission (CR) were included. The 3-year cumulative incidence of measurable residual disease occurrence, relapse and non-relapse mortality after HID HSCT was 28.6% (95% CI: 25.0-32.2), 11.6% (95% CI: 9.0-14.2) and 6.7% (95% CI: 4.7-8.7) respectively. The 3-year probability of event-free survival, leukaemia-free survival (LFS) and overall survival (OS) after HID HSCT was 60.7% (95% CI: 56.9-64.8), 81.7% (95% CI: 78.7-84.9) and 85.6% (95% CI: 82.8-88.4) respectively. In multivariable analysis, AML risk category at diagnosis and comorbidity burdens before HID HSCT were independently associated with LFS and OS. Compared to the older adults (≥ 40 years, n = 355) with AML receiving HID HSCT in CR during the same time period, AYAs have a lower incidence of non-relapse mortality and higher probabilities of LFS and OS. Thus, we firstly confirmed the safety and efficacy of HID HSCT in AYAs with AML-CR.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Humanos , Adolescente , Adulto Jovem , Idoso , Adulto , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Indução de Remissão , Estudos Retrospectivos
3.
Ann Hematol ; 102(4): 907-916, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36757444

RESUMO

The rate of intensive care unit (ICU) mortality in patients with hematologic malignancies is high. The risk factors for this were inconsistent across several previous studies, and there is currently no accepted consensus around risk factors for these patients. We aimed to identify which prognostic factors were associated with ICU mortality in critically ill patients with hematologic malignancies, nearly half of which were allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients. In addition, we aimed to compare the characteristics and clinical outcomes of patients with and without allogenic allo-HSCT. In total, 217 patients with hematologic malignancies were enrolled consecutive, 119 (54.8%) of whom underwent HSCT (allo-HSCT: n = 115). All survivors were followed up with until August 1, 2022. The rate of ICU mortality in this cohort was 54.4%: 55.5 and 53.1% for the patients with and without HSCT, respectively (p = 0.724). The probabilities of survival after ICU admission were also comparable between the patients who had allo-HSCT and those who did not. A multivariable analysis revealed that cerebrovascular disease, hyperlactic acidemia on the day of ICU admission, lower platelet count, use of vasoactive drugs, and absence of noninvasive ventilation on the day of ICU admission were independent risk factors for ICU mortality. For patients with three to five of these risk factors, the rate of ICU mortality was as high as 84.6%, which was significantly higher than that of other patients. In this study, the ICU mortality rate in patients with hematologic malignancies was still high, particularly for those with multiple risk factors. However, allo-HSCT was not found to be a risk factor for ICU mortality.


Assuntos
Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Humanos , Prognóstico , Estudos Retrospectivos , Unidades de Terapia Intensiva , Transplante Homólogo , Fatores de Risco , Transplante de Células-Tronco Hematopoéticas/efeitos adversos
4.
Environ Sci Technol ; 57(18): 7174-7184, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37079659

RESUMO

Desert carbon sequestration plays an active role in promoting carbon neutralization. However, the current understanding of the effect of hydrothermal interactions and soil properties on desert carbon sequestration after precipitation remains unclear. Based on the experiment in the hinterland of the Taklimakan Desert, we found that the heavy precipitation will accelerate the weakening of abiotic carbon sequestration in deserts under the background of global warming and intensified water cycle. The high soil moisture can significantly stimulate sand to release CO2 at an incredible speed by rapidly increasing microbial activity and organic matter diffusion. At this time, the CO2 flux in the shifting sand was synergistically affected by soil temperature and soil moisture. As far as soil properties are concerned, with less organic carbon substrate and stronger soil alkalinity, the carbon sequestration of shifting sand is gradually highlighted and strengthened at low temperature. On the contrary, the carbon sequestration of shifting sand is gradually weakened. Our study provides a new way to assess the contribution of desert to the global carbon cycle and improve the accuracy and scope of application.


Assuntos
Sequestro de Carbono , Ecossistema , Clima Desértico , Dióxido de Carbono , Solo/química , Carbono , China
5.
J Clin Lab Anal ; 37(23-24): e24989, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37975330

RESUMO

BACKGROUND: Because of the deficiencies of traditional methods in multivalent rotavirus vaccine potency detection, a cell-based quantitative RT-qPCR assay (C-QPA) was established and validated for specificity, precision, and accuracy. METHODS: In order to further validate the robustness of this method in actual titer detection, the linear range and the practical application under different conditions were tested using monovalent and trivalent rotavirus samples and standards. RESULTS: Results showed that the linear range was 2.0-6.5, 3.9-8.3, and 3.5-8.1 UI (unit of infectivity) for G2, G3, and G4, respectively. Besides, unknown sample with high titer exceeding the linear range can be calculated by dilution. The UIs of serotypes G2, G3, and G4 in monovalent and trivalent rotavirus samples showed a relative deviation ≤4.10%, and the monovalent samples of the same serotype with or without protective agents showed a relative deviation ≤4.28%; the coefficient of variation (CV) of at least 176 tests (548 individual runs) of 3 in vitro-transcribed RNA standards with certain concentrations was not higher than 6.50%; the results of the trivalent samples tested by more than 149 times in 5 years (467 individual runs) showed the CVs lower than 12.66%; 15 samples detected by one laboratory showed a CV lower than 9.83%, while other three samples tested by two independent laboratories showed a CV lower than 6.90%. CONCLUSION: In summary, the C-QPA has good linearity, durability, repeatability, and reproducibility in practical application and has been proved by the authority to be widely used in the production, quality control and release of the recently licensed trivalent vaccine in China.


Assuntos
Infecções por Rotavirus , Vacinas contra Rotavirus , Rotavirus , Humanos , Reprodutibilidade dos Testes , Rotavirus/genética , Infecções por Rotavirus/diagnóstico , China
6.
Anim Biotechnol ; 34(8): 3796-3807, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37409454

RESUMO

The experiment investigated the impacts of FA on the proliferation of bovine mammary gland epithelial cells (BMECs) and to investigate the underlying mechanisms. Supplementation of 10 µM FA elevated the mRNA expression of proliferating cell nuclear antigen (PCNA), cyclin A2 and cyclin D1, and protein expression of PCNA and Cyclin A1. The mRNA and protein expression of B-cell lymphoma-2 (BCL2) and the BCL2 to BCL2 associated X 4 (BAX4) ratio elevated, while that of BAX, Caspase-3 and Caspase-9 reduced by FA. Both Akt and mTOR signaling pathways were activated by FA. Moreover, the stimulation of BMECs proliferation, the alteration of proliferative genes and protein expression, the change of apoptotic genes and protein expression, and the activation of mTOR signaling pathway caused by FA were obstructed by Akt inhibitor. Suppression of mTOR with Rapamycin reversed the FA-modulated promotion of BMECs proliferation and change of proliferous genes and protein expression, with no impact on mRNA or proteins expression related to apoptosis and FA-activated Akt signaling pathway. Supplementation of rumen-protected FA in cow diets evaluated milk yields and serum insulin-like growth factor-1 and estradiol levels. The results implied that the proliferation of BMECs was stimulated by FA through the Akt-mTOR signaling pathway.


Assuntos
Glândulas Mamárias Animais , Proteínas Proto-Oncogênicas c-akt , Feminino , Bovinos , Animais , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Antígeno Nuclear de Célula em Proliferação/farmacologia , Glândulas Mamárias Animais/metabolismo , Serina-Treonina Quinases TOR/genética , Dieta/veterinária , Leite/metabolismo , Células Epiteliais/metabolismo , RNA Mensageiro/genética , Lactação/genética , Suplementos Nutricionais , Ácido Fólico/farmacologia , Ácido Fólico/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/farmacologia
7.
Ecotoxicol Environ Saf ; 265: 115516, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37757626

RESUMO

Mono-2-ethylhexyl phthalic acid (MEHP) is the most toxic metabolite of plasticizer di-2-ethylhexyl phthalic acid (DEHP), and there is limited information available on the effects of MEHP on neurotoxicity. This study aims to examine the neurotoxicity of MEHP and preliminarily explore its potential molecular mechanisms. We found that MEHP impeded the growth of zebrafish embryos and the neurodevelopmental-related gene expression at environmentally relevant concentrations. MEHP exposure also induces oxidative stress response and brain cell apoptosis accompanied by a decrease in acetylcholinesterase (AChE) activity in zebrafish larvae. RNA-Seq and bioinformatics analysis showed that MEHP treatment altered the nervous system, neurogenic diseases, and visual perception pathways. The locomotor activity in dark-to-light cycles and phototaxis test confirmed the abnormal neural behavior of zebrafish larvae. Besides, the immune system has produced a large number of differentially expressed genes related to neural regulation. Inflammatory factor IL1ß and IL-17 signaling pathways highly respond to MEHP, indicating that inflammation caused by immune system imbalance is a potential mechanism of MEHP-induced neurotoxicity. This study expands the understanding of the toxicity and molecular mechanisms of MEHP, providing a new perspective for in-depth neurotoxicity exploration of similar compounds.

8.
J Formos Med Assoc ; 122(6): 458-469, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36725372

RESUMO

BACKGROUND: Trend pattern analysis are lacking for hepatitis B surface antigen (HBsAg) kinetics in chronic hepatitis B (CHB) patients during nucleos(t)ide analogue (Nuc) therapy. We evaluated the trend patterns of HBsAg kinetics by time series analysis and forecasting times to HBsAg seroclearance accordingly. METHODS: A total of 116 CHB patients with documented three-month HBsAg levels during the previous more than five years of Nuc therapy were included. The piecewise linear trends of the autoregressive-moving average (ARMA) model were used for time series analysis of HBsAg kinetics trends. Best fitted models were created for each patient using HBsAg datasets with backtracking capability. Predicted time to HBsAg seroclearance was calculated accordingly. RESULTS: Four trend patterns of HBsAg kinetics were found: no trend (n = 22, 19.0%), single trend (n = 16, 13.8%), biphasic trend with rapid-slow decline (n = 56, 48.2%) and biphasic trend with rise-decline (n = 22, 19.0%). Except for no-trend patients, the trend became slow reduction as HBsAg declined. Only 6.1% of patients continued rapid decline when the initial HBsAg of the last trend reached <100 IU/mL. Last trend slopes < -10 and rise-decline patterns indicate greater chances of achieving HBsAg seroclearance within two years. CONCLUSION: Best fitted ARMA models of HBsAg kinetics can be created individually for patients during Nuc therapy. About 67.2% patients have biphasic trend patterns, suggesting the dynamic nature of HBsAg kinetics over time. Trend patterns and last trend slopes predict individual times to HBsAg seroclearance.


Assuntos
Antígenos de Superfície da Hepatite B , Hepatite B Crônica , Humanos , Hepatite B Crônica/tratamento farmacológico , Vírus da Hepatite B/genética , Antivirais/uso terapêutico , DNA Viral , Antígenos E da Hepatite B
9.
Chin J Traumatol ; 25(1): 27-31, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34702632

RESUMO

PURPOSE: To investigate the clinical value of urine interleukin-18 (IL-8), neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) for the early diagnosis of acute kidney injury (AKI) in patients with ureteroscopic lithotripsy (URL) related urosepsis. METHODS: A retrospective study was carried out in 157 patients with urosepsis after URL. The patients were divided into AKI group and non-AKI group according to the Kidigo guideline and urine IL-8, NGAL and KIM-1 levels were detected by enzyme-linked immunosorbent assay at 0, 4, 12, 24 and 48 h after the surgery. Receiver operating characteristic curve (ROC) was used to evaluate the diagnostic value of these three biomarkers for postoperative AKI. RESULTS: The level of urine IL-8, NGAL and KIM-1 in AKI group was significantly higher than that in non-AKI group at 4, 12, 24 and 48 h (p < 0.01). The ROC analysis showed the combined detection of urine IL-8, NGAL and KIM-1 at 12 h had a larger area under curve (AUC) than a single marker (0.997, 95% CI: 0.991-0.998), and the sensitivity and specificity were 98.2% and 96.7%, respectively. Pearson correlation analysis showed that the levels of urine NGAL at 4, 12, 24 and 48 h in AKI patients were positively correlated with the levels of urine KIM-1 and IL-18 (p < 0.01). CONCLUSION: AKI could be quickly recognized by the elevated level of urine IL-8, NGAL and KIM-1 in patients with URL-related urosepsis. Combined detection of the three urine biomarkers at 12 h after surgery had a better diagnostic performance, which may be an important reference for the early diagnosis of AKI.


Assuntos
Injúria Renal Aguda , Litotripsia , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Biomarcadores , Diagnóstico Precoce , Receptor Celular 1 do Vírus da Hepatite A , Humanos , Interleucina-18 , Interleucina-8 , Lipocalina-2 , Estudos Retrospectivos , Ureteroscopia
10.
Anim Biotechnol ; 31(6): 512-519, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31253064

RESUMO

The study evaluated the effects of branched-chain volatile fatty acids (BCVFA) and fibrolytic enzyme (FE) on rumen development in calves. Forty Holstein male calves at the same ages (15 ± 2.5 days of age) and weights (45 ± 3.3 kg of body weight [BW]) were assigned randomly to four groups with a 2 × 2 factorial arrangement of treatments. Supplemental BCVFA (0 g/d or 18 g/d) and FE (0 g/d or 1.83 g/d) were fed to calves. Data were analyzed as a 2 × 2 factorial arrangement random design by the mixed procedure of SAS. The BCVFA × FE interaction was observed for ruminal propionate, blood growth hormone (GH) and insulin-like growth factor-1 (IGF-1), and GH receptor (GHR) and IGF-1 receptor (IGF-1R) expression in the rumen mucosa. Dry matter intake was higher for BCVFA addition. The higher average daily gain and ruminal volatile fatty acids were observed for BCVFA or FE addition. Stomach weight and the length and width of rumen papillae were higher for BCVFA addition. The higher expression of GHR, IGF-1R and 3-hydroxy-3-methylglutaryl-CoA synthase 1 in rumen mucosa, and blood GH and IGF-1 were observed with BCVFA or FE addition. Blood ß-hydroxybutyrate and acetoacetate were higher for BCVFA addition. The results indicated that rumen development was promoted by BCVFA, but was not affected with FE addition in calves.


Assuntos
Ração Animal , Celulase , Ácidos Graxos Voláteis/farmacologia , Rúmen , Animais , Bovinos , Endo-1,4-beta-Xilanases , Distribuição Aleatória , Rúmen/efeitos dos fármacos , Rúmen/crescimento & desenvolvimento , Rúmen/metabolismo , Aumento de Peso/efeitos dos fármacos
11.
Chemistry ; 25(15): 3930-3938, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30561861

RESUMO

A series of three Mo2 dimers bridged by a meta-phenylene group has been studied in terms of electronic coupling (EC) and electron transfer (ET) in comparison with the para isomers. Optical analyses on the mixed-valence complexes indicate that by replacing a para-phenylene bridge with a meta one, the EC between the two Mo2 centers is dramatically weakened; consequently, the ET rates (ket ) are lowered by two to three orders of magnitude. In the para series, the EC parameters (Hab ) and ET rates (ket ) are greatly affected by O/S atomic alternation of the bridging ligand. However, for the meta analogues, similar EC and ET parameters are obtained, that is, Hab =300-400 cm-1 and ket ≈109  s-1 . These results suggest that through-σ-bond and/or through-space coupling channels become operative as the π conjugation is disabled. DFT calculations reveal that destructive quantum interference features seen for the meta series arise from the cancellation of two π-conjugated coupling pathways.

12.
Neurochem Res ; 44(11): 2527-2535, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31515677

RESUMO

Mas-related G-protein-coupled receptor subtype C (MrgC) has been shown to play an important role in the development of bone cancer pain. Ubiquitination is reported to participate in pain. However, whether MrgC ubiquitination plays a role in bone cancer pain remains unclear. To answer this question, we designed and performed this study. Osteosarcoma cells were implanted into the intramedullary space of the right femurs of C3H/HeJ mice to induce progressive bone cancer pain. MrgC agonist bovine adrenal medulla 8-22 (BAM 8-22) or MrgC antagonist anti-MrgC antibody were injected intrathecally on day 14 after bone cancer pain was successfully induced. The pain behaviors, the MrgC ubiquitination levels and intracellular calcium concentration in spinal neurons were measured before and after injection, respectively. With comparison to normal and sham group, mice in tumor group exhibited serious bone cancer pain on day 14, and the level of MrgC ubiquitination and intracellular calcium concentration in spinal neurons was significantly higher. Intrathecal injection of BAM 8-22 significantly alleviated bone cancer pain, increased the MrgC ubiquitination level and decreased intracellular calcium concentration in spinal neurons; however, these effects were reversed by administration of anti-MrgC antibody. Our study reveals that MrgC ubiquitination participates in the production and maintenance of bone cancer pain in mice, possibly through the regulation of intracellular calcium concentration in mice spinal neurons.


Assuntos
Neoplasias Ósseas/metabolismo , Cálcio/metabolismo , Dor do Câncer/metabolismo , Neurônios/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Medula Espinal/metabolismo , Analgésicos/uso terapêutico , Animais , Anticorpos/imunologia , Dor do Câncer/tratamento farmacológico , Linhagem Celular Tumoral , Masculino , Camundongos Endogâmicos C3H , Fragmentos de Peptídeos/uso terapêutico , Processamento de Proteína Pós-Traducional , Coelhos , Receptores Acoplados a Proteínas G/imunologia , Medula Espinal/citologia , Ubiquitinação
13.
J Sci Food Agric ; 99(13): 5826-5833, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31206694

RESUMO

BACKGROUND: Considering the insufficient ruminal synthesis of folic acid (FA), the higher degradability of FA, and the reduction of sodium selenite (SS) by ruminal microbes into non-absorbable elemental Se, this study evaluated the effects of rumen-protected FA (RPFA) and rumen-protected SS (RPSS) on lactation performance, nutrient digestion and blood metabolites in dairy cows. RESULTS: Dry matter (DM) intake and milk composition were unaltered, milk and milk fat yields were higher for both supplements, and milk protein yield was higher for RPFA addition. Digestibility of DM, neutral detergent fibre and acid detergent fibre was higher for both supplements, whereas that of organic matter and crude protein was higher for RPFA addition. Ruminal pH and ammonia N were lower, and concentration of total volatile fatty acids was higher for both supplements. Activity of cellobiase and xylanase was higher for RPFA addition, whereas that of pectinase and protease was higher for both supplements. The populations of total ruminal fungi, protozoa, Ruminococcus flavefaciens and Butyrivibrio fibrisolvens were higher for both supplements. The RPFA × RPSS interaction was significant for α-amylase activity, total ruminal bacteria and R. albus populations; these three variables were increased by RPSS but the increase was greater when cows were also fed RPFA. CONCLUSION: The results indicated that addition of RPFA or RPSS improved lactation performance, nutrient digestibility and ruminal fermentation in dairy cows by stimulating ruminal microbial growth and enzyme activity. © 2019 Society of Chemical Industry.


Assuntos
Bovinos/fisiologia , Suplementos Nutricionais/análise , Ácido Fólico/administração & dosagem , Rúmen/metabolismo , Selenito de Sódio/administração & dosagem , Amônia/metabolismo , Animais , Bovinos/microbiologia , Digestão , Ácidos Graxos Voláteis/metabolismo , Feminino , Fermentação , Ácido Fólico/metabolismo , Microbioma Gastrointestinal , Lactação , Leite/química , Leite/metabolismo , Rúmen/microbiologia , Selenito de Sódio/metabolismo
14.
Phys Rev Lett ; 120(16): 165001, 2018 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-29756949

RESUMO

The first octahedral spherical hohlraum energetics experiment is accomplished at the SGIII laser facility. For the first time, the 32 laser beams are injected into the octahedral spherical hohlraum through six laser entrance holes. Two techniques are used to diagnose the radiation field of the octahedral spherical hohlraum in order to obtain comprehensive experimental data. The radiation flux streaming out of laser entrance holes is measured by six flat-response x-ray detectors (FXRDs) and four M-band x-ray detectors, which are placed at different locations of the SGIII target chamber. The radiation temperature is derived from the measured flux of FXRD by using the blackbody assumption. The peak radiation temperature inside hohlraum is determined by the shock wave technique. The experimental results show that the octahedral spherical hohlraum radiation temperature is in the range of 170-182 eV with drive laser energies of 71 kJ to 84 kJ. The radiation temperature inside the hohlraum determined by the shock wave technique is about 175 eV at 71 kJ. For the flat-top laser pulse of 3 ns, the conversion efficiency of gas-filled octahedral spherical hohlraum from laser into soft x rays is about 80% according to the two-dimensional numerical simulation.

15.
Inorg Chem ; 57(12): 7455-7467, 2018 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-29809000

RESUMO

The large bridging ligand 9,10-anthracenedicarboxylate and its thiolated derivatives have been employed to assemble two dimolybdenum complex units and develop three Mo2 dimers, [Mo2(DAniF)3]2(µ-9,10-O2CC14H8CO2), [Mo2(DAniF)3]2(µ-9,10-OSCC14H8COS), and [Mo2(DAniF)3]2(µ-9,10-S2CC14H8CS2) (DAniF = N, N'-di( p-anisyl)formamidinate), for the study of conformation dependence of the electronic coupling between the two Mo2 centers. These compounds feature a large deviation of the central anthracene ring from the plane defined by the Mo-Mo bond vectors, with the torsion angles (ϕ = 50-76°) increasing as the chelating atoms of the bridging ligand vary from O to S. Consequently, the corresponding mixed-valence complexes do not exhibit characteristic intervalence charge transfer absorptions in the near-IR spectra, in contrast to the phenylene and naphthalene analogues, from which these systems are assigned to the Class I in Robin-Day's scheme. Together with the phenylene and naphthalene series, the nine total mixed-valence complexes in three series complete a transition from the electronically uncoupled Class I to the strongly coupled Class II-III borderline via moderately coupled Class II and permit a systematic mapping of the bridge conformation effects on electronic coupling. Density functional theory calculations show that the HOMO-LUMO energy gap, corresponding to the metal (δ) to ligand (π*) transition energy, and the magnitude of HOMO-HOMO-1 splitting in energy are linearly related to cos2 ϕ. Therefore, our experimental and theoretical results concur to indicate that the coupling strength decreases in the order of the bridging units: phenylene > naphthalene > anthracene, which verifies the through-bond superexchange mechanism for electronic coupling and electron transfer.

16.
J Sci Food Agric ; 98(6): 2098-2104, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28941230

RESUMO

BACKGROUND: Lactation performance of dairy cow has considerably increased with animal breeding and management improvement in recent years. Ruminal net synthesised pantothenic acid is insufficient to meet the requirement of high producing dairy cows. The objective was to investigate the effects of rumen-protected pantothenate (RPP) on lactation performance, ruminal fermentation, nutrient digestion and blood metabolites in dairy cows. RESULTS: Dry matter (DM) intake tended to increase, whereas milk yields, milk fat percentage and yield, body condition score (BCS) changes and net energy output except for maintenance increased linearly with increasing RPP supplementation. Ruminal pH and ammonia N concentration tended to decrease, total VFA tended to increase, while acetate-to-propionate ratio increased linearly with increasing RPP supplementation. Digestibilities of DM, organic matter and crude protein increased linearly, but neutral detergent fibre and acid detergent fibre digestibility tended to increase. Blood glucose, total protein, non-esterified fatty acids, pantothenic acid, pantothenate kinase, succinyl CoA, acyl carrier protein and acetyl CoA also increased linearly with increasing RPP supplementation. CONCLUSION: The results indicated that supplementary RPP improved lactation performance, nutrient digestion and blood parameters in a dose-dependent manner, and the optimal dose was 12 g RPP per cow per day in the current study. © 2017 Society of Chemical Industry.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Suplementos Nutricionais/estatística & dados numéricos , Ácido Pantotênico/administração & dosagem , Rúmen/metabolismo , Amônia/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Glicemia/análise , Bovinos/sangue , Bovinos/microbiologia , Suplementos Nutricionais/análise , Digestão , Feminino , Fermentação , Lactação , Leite/metabolismo , Silagem/análise
17.
Environ Microbiol ; 18(2): 525-41, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25471302

RESUMO

Currently, knowledge about the impact of high-grain (HG) feeding on rumen microbiota and metabolome is limited. In this study, a combination of the 454 pyrosequencing strategy and the mass spectrometry-based metabolomics technique was applied to investigate the effects of increased dietary grain (0%, 25% and 50% maize grain) on changes in whole ruminal microbiota and their metabolites using goat as a ruminant model. We observed a significant influence of HG feeding in shaping the ruminal bacterial community structure, diversity and composition, with an overall dominance of bacteria of the phylum Firmicutes along with a low abundance of Bacteriodetes in the HG group. High-grain feeding increased the number of ciliate and methanogens, and decreased the density of anaerobic fungi and the richness of the archaeal community. The metabolomics analysis revealed that HG feeding increased the levels of several toxic, inflammatory and unnatural compounds, including endotoxin, tryptamine, tyramine, histamine and phenylacetate. Correlation analysis on the combined datasets revealed some potential relationships between ruminal metabolites and certain microbial species. Information about these relationships may prove useful in either direct (therapeutic) or indirect (dietary) interventions for ruminal disorders due to microbial compositional shifts, such as ruminal acidosis.


Assuntos
Dieta , Grão Comestível/metabolismo , Microbioma Gastrointestinal/fisiologia , Cabras/microbiologia , Metaboloma/fisiologia , Rúmen/microbiologia , Acidose , Animais , Archaea/isolamento & purificação , Bactérias/isolamento & purificação , Cilióforos/isolamento & purificação , Fungos/isolamento & purificação , Metabolômica , Zea mays/metabolismo
18.
Phys Rev Lett ; 117(2): 025002, 2016 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-27447512

RESUMO

The first spherical hohlraum energetics experiment is accomplished on the SGIII-prototype laser facility. In the experiment, the radiation temperature is measured by using an array of flat-response x-ray detectors (FXRDs) through a laser entrance hole at four different angles. The radiation temperature and M-band fraction inside the hohlraum are determined by the shock wave technique. The experimental observations indicate that the radiation temperatures measured by the FXRDs depend on the observation angles and are related to the view field. According to the experimental results, the conversion efficiency of the vacuum spherical hohlraum is in the range from 60% to 80%. Although this conversion efficiency is less than the conversion efficiency of the near vacuum hohlraum on the National Ignition Facility, it is consistent with that of the cylindrical hohlraums used on the NOVA and the SGIII-prototype at the same energy scale.

19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(8): 2414-9, 2016 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-30073826

RESUMO

Surface broadband emissivity in the thermal infrared region is an important parameteras for the studies of the surface energy balance. This paper analyzed and offered an equation to estimate the surface broadband emissivity for the spectral domains 8~14 µm against the MODIS data, and then, the distribution characteristic of surface emissivity for Taklimakan Desert was obtained with this equation. Firstly, along two highways crossing the Taklimakan Desert, twenty sample sites were selected and their spectral of broadband emissivity were observed with Fourier Transform Infrared spectrometer (FTIR). Secondly, using the Moderate Resolution Imaging Spectrometer (MODIS) land surface temperature and emissivity product MOD11A1 and MOD11C1, derived emissivities in three thermal infrared channels 29 (8.4~8.7 µm), 31 (10.78~11.28 µm) and 32 (11.77~12.27 µm) and MODIS surface reflectance products MOD09A1, derived reflectance in near-infrared channel 7 (2.105~2.155 µm), developing an empirical regression equation to convert these spectral emissivities and reflectance to a broadband emissivity. The FTIR data were used to determine the coefficients of the regression equation, another part of FTIR data were used to investigate the accuracy of equation. It was found that the equation consist of MODIS channels 29, 31 and 32 has more accuracy; furthermore, the accuracy is improved when channel 7 data was added in the regression equation. The root mean square error (RMSE) and Bias were 0.004 5 and 0.000 1, respectively. Comparing to other six equations originated from literatures, which also estimate the surface broadband emissivity from narrowband emissivities. The RMSE and Bias of our equation are lower one order and two orders of magnitude than other six equations, respectively. Lastly, our equation is applied in the Taklimakan Desert area to build a distribution image of emissivity based on MODIS data. It demonstrates that the emissivity of Taklimakan Desert is in the range of 0.880~0.910 over the central regions, the averaged value is 0.906; The emissivity is in the range of 0.910~0.940 where the areas covered by spare vegetation; The emissivity is in range of 0.950~0.980 where the regions near to the oasis.

20.
J Surg Res ; 199(2): 601-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26163326

RESUMO

BACKGROUND: Simvastatin reduces ventilator-induced lung injury and is regularly used in clinical practice. This study aimed to test the hypotheses that long-term use of simvastatin could affect the incidence and severity of ventilator-induced lung injury after mechanical ventilation, and the process may involve heme oxygenase-1 (HO-1). MATERIALS AND METHODS: Forty healthy adult Sprague-Dawley rats were randomly divided into four groups, namely control, ventilation, simvastatin, and simvastatin + ventilation groups. Saline (control and ventilation groups) or 10 mg kg(-1) d(-1) simvastatin (simvastatin and simvastatin + ventilation groups) was administered by gavage to the animals for 4 wk. Mechanical ventilation (tidal volume 50 mL/kg) was then applied for 4 h to the ventilation and simvastatin + ventilation groups. Lung tissues were harvested for hematoxylin-eosin staining and pathologic examination, and HO-1 contents were measured by immunoblotting and polymerase chain reaction. RESULTS: A severe pathologic damage was observed in rats that underwent mechanical ventilation. Interestingly, protein concentration, wet/dry weight ratio, myeloperoxidase activity, and malondialdehyde level were increased, and superoxide dismutase activity decreased, in lung tissues after mechanical ventilation. The pathologic damage was substantially alleviated in rats treated with simvastatin before mechanical ventilation: reduced protein concentration, wet/dry weight ratio, myeloperoxidase activity, and malondialdehyde level, and increased superoxide dismutase activity in lung tissues, compared with the ventilation group. Both mechanical ventilation and simvastatin administration induced HO-1 messenger RNA and protein expression in lung tissues. CONCLUSIONS: Long-term administration of simvastatin significantly reduces the inflammatory response and pulmonary injury induced by mechanical ventilation, potentially by upregulating HO-1 in lung tissues.


Assuntos
Heme Oxigenase (Desciclizante)/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Respiração Artificial/efeitos adversos , Sinvastatina/administração & dosagem , Lesão Pulmonar Induzida por Ventilação Mecânica/prevenção & controle , Animais , Modelos Animais de Doenças , Pulmão/enzimologia , Pulmão/patologia , Malondialdeído/metabolismo , Peroxidase/metabolismo , Distribuição Aleatória , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Regulação para Cima/efeitos dos fármacos , Lesão Pulmonar Induzida por Ventilação Mecânica/enzimologia , Lesão Pulmonar Induzida por Ventilação Mecânica/patologia
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