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1.
Nature ; 600(7887): 49-53, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34666337

RESUMO

The distribution of water in the Moon's interior carries implications for the origin of the Moon1, the crystallization of the lunar magma ocean2 and the duration of lunar volcanism2. The Chang'e-5 mission returned some of the youngest mare basalt samples reported so far, dated at 2.0 billion years ago (Ga)3, from the northwestern Procellarum KREEP Terrane, providing a probe into the spatiotemporal evolution of lunar water. Here we report the water abundances and hydrogen isotope compositions of apatite and ilmenite-hosted melt inclusions from the Chang'e-5 basalts. We derive a maximum water abundance of 283 ± 22 µg g-1 and a deuterium/hydrogen ratio of (1.06 ± 0.25) × 10-4 for the parent magma. Accounting for low-degree partial melting of the depleted mantle followed by extensive magma fractional crystallization4, we estimate a maximum mantle water abundance of 1-5 µg g-1, suggesting that the Moon's youngest volcanism was not driven by abundant water in its mantle source. Such a modest water content for the Chang'e-5 basalt mantle source region is at the low end of the range estimated from mare basalts that erupted from around 4.0 Ga to 2.8 Ga (refs. 5,6), suggesting that the mantle source of the Chang'e-5 basalts had become dehydrated by 2.0 Ga through previous melt extraction from the Procellarum KREEP Terrane mantle during prolonged volcanic activity.

2.
Analyst ; 149(10): 2806-2811, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38683246

RESUMO

We design a p-aminothiophenol (pATP) modified Au/ITO chip to determine nitrite ions in lake water by a ratiometric surface-enhanced Raman scattering (SERS) method based on nitrite ions triggering the transformation of pATP to p,p'-dimercaptoazobenzene (DMAB). Intriguingly, by using the SERS peak (at 1008 cm-1) from benzoic ring deforming as an internal standard instead of the traditional peak at 1080 cm-1, the detection sensitivity of the method was improved 10 times.

3.
Pak J Pharm Sci ; 37(2(Special)): 423-428, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38822545

RESUMO

This study assessed the inhibitory effect of sodium valproate (VPA) on apoptosis of cardiomyocytes in lethally scalded rats. The model of a 50% total body surface area (TBSA) third-degree full-thickness scald was produced, 48 male SD rats were randomly divided into three groups (n = 16), the sham group and the scald group were given an intraperitoneal injection of 0.25ml of saline, the scald +VPA group was given an intraperitoneal injection of VPA (300 mg/kg) after scalded, Each group was subdivided into two subgroups (n=8) according to the two observation time points of 3h and 6h after scald. Apoptotic cardiomyocytes were observed, and myocardial tissue levels of nitric oxide (NO), cysteine protease-3 (caspase-3) activity, hypoxia-inducible factor-1α (HIF-1α), inducible nitric oxide synthase (iNOS), BCL2/adenovirus E1B interacting protein 3 (BNIP3) and caspase-3 protein were measured. Compared with sham scald group, severe scald elevated CK-MB, cardiomyocyte apoptosis rate, caspase-3 activity and protein levels, NO content, and HIF-1α signalling pathway proteins; whereas VPA decreased CK-MB, cardiomyocyte apoptosis rate and inhibited HIF-1α signalling pathway protein expression. In conclusion, these results suggested that VPA inhibited early cardiomyocyte apoptosis and attenuated myocardial injury in lethally scalded rats, which may be related to the regulation of the HIF-1α signalling pathway.


Assuntos
Apoptose , Queimaduras , Subunidade alfa do Fator 1 Induzível por Hipóxia , Miócitos Cardíacos , Ácido Valproico , Animais , Masculino , Ratos , Apoptose/efeitos dos fármacos , Queimaduras/tratamento farmacológico , Queimaduras/metabolismo , Queimaduras/patologia , Caspase 3/metabolismo , Modelos Animais de Doenças , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos Sprague-Dawley , Ácido Valproico/farmacologia
4.
J Surg Res ; 287: 24-32, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36863270

RESUMO

INTRODUCTION: To establish an animal model of delayed intravenous resuscitation following seawater immersion after hemorrhagic shock (HS). METHODS: Adult male SD rats were randomly divided into three groups: group NI (HS with no immersion), group SI (HS with skin immersion), and group VI (HS with visceral immersion). Controlled HS in rats was induced by withdrawing 45% of the calculated total blood volume within 30 min. In SI group, immediately after blood loss, 0.5 cm below the xiphoid process was immersed in artificial seawater, at (23 ± 1) °C, for 30 min. In VI group, the rats were performed by laparotomy and the abdominal organs were immersed in (23 ± 1) °C seawater for 30 min. Two hours after seawater immersion, the extractive blood and lactated Ringer's solution were delivered intravenously. The mean arterial pressure (MAP), lactate, and other biological parameters were investigated in different time points. The survival rate of 24 h after HS was recorded. RESULTS: After seawater immersion following HS, MAP and abdominal viscera blood flow decreased significantly, and the plasma levels of lactate and the organ function parameters were increased than the baseline. The above changes in VI group were more serious than those in SI and NI group, especially in myocardial and small intestine damage. The hypothermia, hypercoagulation, and metabolic acidosis were also observed after seawater immersion; the injury was more severely in VI group than that of SI group. However, the plasma levels of sodium, potassium, chlorine, and calcium in VI group were significantly higher than those before injury and in the other two groups. In the VI group, the level of plasma osmolality in instant, 2 h, and 5 h after immersion was 111%, 109%, and 108% of the SI group, respectively, all P < 0.01. The 24-h survival rate of VI group was 25%, which was significantly lower than that of SI group (50%) and NI group (70%), P < 0.05. CONCLUSIONS: The model fully simulated the key damage factors and field treatment conditions, reflected the effects of low temperature and hypertonic damage caused by seawater immersion on the severity and prognosis of naval combat wounds, and provided a practical and reliable animal model for the study of field treatment technology of marine combat shock.


Assuntos
Choque Hemorrágico , Ratos , Masculino , Animais , Choque Hemorrágico/complicações , Choque Hemorrágico/terapia , Ratos Sprague-Dawley , Modelos Animais de Doenças , Hemorragia , Ressuscitação , Ácido Láctico
5.
Bioorg Chem ; 133: 106403, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36801790

RESUMO

Our previous studies suggested that N-phenyl aromatic amides are a class of promising xanthine oxidase (XO) inhibitor chemotypes. In this effort, several series of N-phenyl aromatic amide derivatives (4a-h, 5-9, 12i-w, 13n, 13o, 13r, 13s, 13t and 13u) were designed and synthesized to carry out an extensive structure-activity relationship (SAR). The investigation provided some valuable SAR information and identified N-(3-(1H-imidazol-1-yl)-4-((2-methylbenzyl)oxy)phenyl)-1H-imidazole-4-carboxamide (12r, IC50 = 0.028 µM) as the most potent XO inhibitor with close in vitro potency to that of topiroxostat (IC50 = 0.017 µM). Molecular docking and molecular dynamics simulation rationalized the binding affinity through a series of strong interactions with the residues Glu1261, Asn768, Thr1010, Arg880, Glu802, etc. In vivo hypouricemic studies also suggested that the uric acid lowering effect of compound 12r was improved compared with the lead g25 (30.61 % vs 22.4 % reduction in uric acid levels at 1 h; 25.91 % vs 21.7 % reduction in AUC of uric acid) . Pharmacokinetic studies revealed that compound 12r presented a short t1/2 of 0.25 h after oral administration. In addition, 12r has non-cytotoxicity against normal cell HK-2. This work may provide some insights for further development of novel amide-based XO inhibitors.


Assuntos
Radioisótopos de Nitrogênio , Xantina Oxidase , Amidas/farmacologia , Inibidores Enzimáticos/química , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade , Ácido Úrico , Xantina Oxidase/antagonistas & inibidores
6.
Bioorg Med Chem Lett ; 60: 128582, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35077850

RESUMO

A series of 4-(phenoxymethyl)-1H-1,2,3-triazole derivatives were designed, synthesized, and evaluated for their xanthine oxidase (XO) inhibitory activities. Among these compounds, 9m emerged as the most effective XO inhibitor with an IC50 value of 0.70 µM, which was approximately 14-fold more potent than allopurinol. Additionally, compound 9m displayed favorable drug-like properties with ligand efficiency (LE) and lipophilic ligand efficiency (LLE) values of 0.33 and 3.41, respectively. We further explored the binding mode of 9m in complex with XO by molecular docking and molecular dynamics studies. In vivo hypouricemic studies also suggested that 9m could effectively lower the serum uric acid levels of rat. In summary, compound 9m could be a promising lead for further development of XO inhibitors.


Assuntos
Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Triazóis/farmacologia , Xantina Oxidase/antagonistas & inibidores , Animais , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Hiperuricemia/induzido quimicamente , Hiperuricemia/tratamento farmacológico , Hiperuricemia/metabolismo , Ligantes , Modelos Moleculares , Estrutura Molecular , Ácido Oxônico , Ratos , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/química , Ácido Úrico/antagonistas & inibidores , Ácido Úrico/sangue , Xantina Oxidase/metabolismo
7.
Org Biomol Chem ; 20(32): 6418-6422, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35876742

RESUMO

A novel cyclization/hydrolysis of 1,5-enenitriles for the synthesis of valuable pyrrolidine-2,4-diones in the aqueous phase using I2 as the catalyst and tert-butyl hydroperoxide (TBHP) as the oxidant is reported. In the presence of the I2/TBHP system, sulfonyl hydrazides produce sulfonyl radicals, which undergo radical addition, intramolecular cyclization, hydrogen abstraction, and hydrolysis to give the final products. The use of the inexpensive and environmentally friendly I2/TBHP catalytic oxidation system in the aqueous phase makes it a benign and sustainable strategy.


Assuntos
Oxidantes , Água , Catálise , Ciclização , Hidrólise , terc-Butil Hidroperóxido
8.
Org Biomol Chem ; 20(35): 7067-7070, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-35993972

RESUMO

The novel polychloromethylation/acyloxylation of 1,6-enynes with chloroalkanes and diacyl peroxides through dual-role designs has been developed to prepare 2-pyrrolidinone derivatives with polychloromethyl units with the use of an inexpensive copper salt under mild conditions. This strategy includes two dual-role designs, not only improving atomic utilization but also allowing a cleaner process. The wide substrate scope and simple reaction conditions demonstrate the practicability of this protocol.

9.
Mikrochim Acta ; 189(5): 207, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35501414

RESUMO

A specific surface-enhanced Raman scattering (SERS) assay for dopamine (DA) based on an azo derivatization reaction is proposed for the first time by preparation of p-aminothiophenol (PATP)-modified composite SERS substrate, composed of metal-organic framework (MIL-101) decorated with Au and Ag nanoparticles. As the result, the SERS method for detection of the azo reaction between PATP and DA exhibits superior sensitivity, selectivity, and stability. A reasonable linearity in the range 10-6 to 10-10 mol∙L-1 is achieved, and the limit of detection is 1.2 × 10-12 mol∙L-1. The reactive SERS assay is free from interference in complex physiological fluid. The feasibility of the proposed SERS method for the detection of DA levels in fetal bovine serum (FBS) samples and human serum samples is validated by HPLC-MS methods, displaying promising application potential in early disease diagnosis.


Assuntos
Nanopartículas Metálicas , Estruturas Metalorgânicas , Compostos de Anilina , Dopamina , Humanos , Prata , Compostos de Sulfidrila
10.
J Bacteriol ; 203(12): e0012721, 2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-33820796

RESUMO

The intracellular bacterial pathogen Brucella causes persistent infections in various mammalian species. To survive and replicate within macrophages, these bacteria must be able to withstand oxidative stresses and express the type IV secretion system (T4SS) to evade host immune responses. The extracytoplasmic function (ECF) sigma factor system is a major signal transduction mechanism in bacteria that senses environmental cues and responds by regulating gene expression. In this study, we defined an ECF σ bcrS and its cognate anti-σ factor abcS in Brucella melitensis M28 by conserved domain analysis and a protein interaction assay. BcrS directly activates an adjacent operon, bcrXQP, that encodes a methionine-rich peptide and a putative methionine sulfoxide reductase system, whereas AbcS is a negative regulator of bcrS and bcrXQP. The bcrS-abcS and bcrXQP operons can be induced by hypochlorous acid and contribute to hypochlorous acid resistance in vitro. Next, RNA sequencing analysis and genome-wide recognition sequence search identified the regulons of BcrS and AbcS. Interestingly, we found that BcrS positively influences T4SS expression in an AbcS-dependent manner and that AbcS also affects T4SS expression independently of BcrS. Last, we demonstrate that abcS is required for the maintenance of persistent infection, while bcrS is dispensable in a mouse infection model. Collectively, we conclude that BcrS and AbcS influence expression of multiple genes responsible for Brucella virulence traits. IMPORTANCEBrucella is a notorious intracellular pathogen that induces chronic infections in animals and humans. To survive and replicate within macrophages, these bacteria require a capacity to withstand oxidative stresses and to express the type IV secretion system (T4SS) to combat host immune responses. In this study, we characterized an extracytoplasmic function sigma/anti-sigma factor system that regulates resistance to reactive chlorine species and T4SS expression, thereby establishing a potential link between two crucial virulence traits of Brucella. Furthermore, the anti-sigma factor AbcS contributes to Brucella persistent infection of mice. Thus, this work provides novel insights into Brucella virulence regulation as well as a potential drug target for fighting Brucella infections.


Assuntos
Brucella melitensis/metabolismo , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Ácido Hipocloroso/farmacologia , Fator sigma/metabolismo , Sistemas de Secreção Tipo IV/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias , Sequência de Bases , Modelos Moleculares , Conformação Proteica , Fator sigma/genética , Sistemas de Secreção Tipo IV/genética
11.
Bioorg Chem ; 117: 105417, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34673452

RESUMO

Our previous work identified a promising isonicotinamide based xanthine oxidase (XO) inhibitor, N-(3-cyano-4-((2-cyanobenzyl)oxy)phenyl)isonicotinamide (1), and concluded that amide is an effective linker in exploring the XO inhibitor chemical space that is completely different from the five-membered ring framework of febuxostat and topiroxostat. Indole, an endogenous bioactive substance and a popular drug construction fragment, was involved in the structural optimization campaign of the present effort. After the installation of some functional groups, N-(1-alkyl-3-cyano-1H-indol-5-yl) was generated and employed to mend the missing H-bond interaction between the 3'-cyano of 1 and Asn768 residue of XO by shortening their distance. In this context, eight kinds of heterocyclic aromatic amide chemotypes were rationally designed and synthesized to investigate the structure-activity relationship (SAR) of amide-based XO inhibitors. The optimized compound a6 (IC50 = 0.018 µM) exhibits 17.2-fold improved potency than the initial compound 1 (IC50 = 0.31 µM). Its potency is comparable to that of topiroxostat (IC50 = 0.013 µM). Molecular docking and molecular dynamics studies proved the existence of the stable H-bond between the cyano group and the Asn768 residue. Moreover, oral administration of a6 (11.8 mg/kg) could effectively reduce serum uric acid levels in an acute hyperuricemia rat model. Liver microsomal stability assay illustrated that compound a6 possesses well metabolic stability in rat liver microsomes. However, the in vivo potency of a6 was much lower than that of topiroxostat, which may be explained by the poor absorption found in the parallel artificial membrane permeability assay (PAMPA). In addition, 6a has non-cytotoxicity against normal cell lines MCF10A and 16HBE. Taken together, this work culminated in the identification of compound 6a as an excellent lead for further exploration of amide-based XO inhibitors.


Assuntos
Amidas/farmacologia , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Indóis/farmacologia , Xantina Oxidase/antagonistas & inibidores , Amidas/química , Amidas/metabolismo , Animais , Bovinos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Feminino , Indóis/química , Masculino , Microssomos Hepáticos/química , Microssomos Hepáticos/metabolismo , Leite/enzimologia , Modelos Moleculares , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Xantina Oxidase/metabolismo
12.
Infect Immun ; 88(11)2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-32778612

RESUMO

Brucella, the causative agent of brucellosis, is a stealthy intracellular pathogen that is highly pathogenic to a range of mammals, including humans. The twin-arginine translocation (Tat) pathway transports folded proteins across the cytoplasmic membrane and has been implicated in virulence in many bacterial pathogens. However, the roles of the Tat system and related substrates in Brucella remain unclear. We report here that disruption of Tat increases the sensitivity of Brucella melitensis M28 to the membrane stressor sodium dodecyl sulfate (SDS), indicating cell envelope defects, as well as to EDTA. In addition, mutating Tat renders M28 bacteria more sensitive to oxidative stress caused by H2O2 Further, loss of Tat significantly attenuates B. melitensis infection in murine macrophages ex vivo Using a mouse model for persistent infection, we demonstrate that Tat is required for full virulence of B. melitensis M28. Genome-wide in silico prediction combined with an in vivo amidase reporter assay indicates that at least 23 proteins are authentic Tat substrates, and they are functionally categorized into solute-binding proteins, oxidoreductases, cell envelope biosynthesis enzymes, and others. A comprehensive deletion study revealed that 6 substrates contribute significantly to Brucella virulence, including an l,d-transpeptidase, an ABC transporter solute-binding protein, and a methionine sulfoxide reductase. Collectively, our work establishes that the Tat pathway plays a critical role in Brucella virulence.


Assuntos
Proteínas de Bactérias/metabolismo , Brucella melitensis/patogenicidade , Brucelose/metabolismo , Sistema de Translocação de Argininas Geminadas/metabolismo , Virulência/fisiologia , Animais , Camundongos , Estresse Fisiológico/fisiologia
13.
J Cell Physiol ; 234(5): 6783-6800, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30317578

RESUMO

Malignant gliomas are aggressive primary neoplasms that originate in the glial cells of the brain or the spine with notable resistance to standard treatment options. We carried out the study with the aim to shed light on the sensitization of resveratrol to temozolomide (TMZ) against glioma through the Wnt signaling pathway. Initially, glioma cell lines with strong resistance to TMZ were selected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Then, the glioma cells were subjected to resveratrol, TMZ, Wnt signaling pathway inhibitors, and activators. Cell survival rate and inhibitory concentration at half maximum value were detected by MTT, apoptosis by flow cytometry, and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining, in vitro proliferation by hanging drop method and ß-catenin translocation into nuclei by TOP/FOP-FLASH assay. The expressions of the Wnt signaling pathway-related and apoptosis-related factors were determined by western blot analysis. Nude mice with glioma xenograft were established to detect tumorigenic ability. Glioma cell lines T98G and U138 which were highly resistant to TMZ were selected for subsequent experiments. Resveratrol increased the efficacy of TMZ by restraining cell proliferation, tumor growth, and promoting cell apoptosis in glioma cells. Resveratrol inhibited Wnt2 and ß-catenin expressions yet elevated GSK-3ß expression. Moreover, the Wnt signaling pathway participates in the sensitivity enhancing of resveratrol to TMZ via regulating O 6 -methylguanine-DNA methyltransferase (MGMT) expression. Resveratrol sensitized TMZ-induced glioma cell apoptosis by repressing the activation of the Wnt signaling pathway and downregulating MGMT expression, which may confer new thoughts to the chemotherapy of glioma.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Resveratrol/farmacologia , Temozolomida/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Camundongos , Camundongos Nus , O(6)-Metilguanina-DNA Metiltransferase/metabolismo
14.
J Cell Mol Med ; 22(11): 5322-5332, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30079502

RESUMO

The carbohydrate response element-binding protein (ChREBP), also referred to as MLXIPL, plays a crucial role in the regulation of glucose and lipid metabolism. Existing studies have shown an association between genetic variations of the ChREBP gene and lipid levels, such as triglycerides and high-density lipoprotein cholesterol. However, mechanistic studies of this association are limited. In this study, bioinformatic analysis revealed that the polymorphism rs1051943A occurs in the complementary binding sequence of miR-1322 in the ChREBP 3'-untranslated region (UTR). Studies of potential mechanisms showed that the A allele could facilitate miR-1322 binding, and luciferase activity significantly decreased when co-transfected with a ChREBP 3'-UTR luciferase reporter vector and miR-1322 mimics in HepG2 cells. Furthermore, miR-1322 significantly regulated the expression of ChREBP downstream genes and reduced the synthesis of lipids. The expression of miR-1322 was up-regulated by glucose and palmitic acid stimulation. Population studies showed that rs1051943-A allele was only found in the Han Chinese and Uighur ethnic groups, different from European populations (G allele frequency = 0.07). In summary, we provide evidence that the rs1051943 A allele creates a functional miR-1322 binding site in ChREBP 3'-UTR and post-transcriptionally down-regulates its expression, possibly associated with levels of plasma lipids and glucose.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Metabolismo dos Lipídeos/genética , Lipídeos/sangue , MicroRNAs/genética , Regiões 3' não Traduzidas , Alelos , Animais , Sítios de Ligação/genética , Glicemia/genética , Regulação da Expressão Gênica/genética , Células Hep G2 , Humanos , Lipídeos/genética , Polimorfismo de Nucleotídeo Único/genética , Elementos de Resposta/genética , Triglicerídeos/genética , Triglicerídeos/metabolismo
15.
J Surg Res ; 225: 166-174, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29605028

RESUMO

BACKGROUND: The carrier of hydroxyethyl starch (HES) may play a critical role in kidney injury in fluid resuscitation. This study aimed mainly to compare effects of pyruvate-enriched saline with normal saline (NS) and acetate Ringer's (AR) solution as a carrier in HES130/0.4 on kidney function in rats subjected to severe burns. METHODS: Using a lethal burn model, 140 rats were randomly allocated in seven groups (n = 20): sham group (group S); no fluid after burn (group N); burn resuscitated with NS (group NS); burn resuscitated with pyruvate saline (group PS); burn resuscitated with AR plus pyruvate-HES (group SP); burn resuscitated with AR plus acetate-HES (group SA), and burn resuscitated with AR plus NS-HES (group SN). A low volume (18.75 mL·kg-1 during 12 h) of HES130/0.4 was infused with the ratio of 1:1 to crystalloids. Renal surface blood flow, blood creatinine and blood urea nitrogen, early sensitive indicators of kidney function: alpha-1 microglobulin, cystatin-C, and neutrophil gelatinase-associated lipocalin in blood and urine, and kidney tissue water contents were determined. Renal histopathological alterations with Paller scores were also measured at 8 h and 24 h after burn (n = 10), respectively. RESULTS: The results showed in a comparable manner that group SP was the best in three HES groups and group PS was superior to group NS in renal preservation; group SP appeared significantly beneficial compared with group PS in renal surface blood flow, cystatin-C, neutrophil gelatinase-associated lipocalin, water contents, and Paller scores at 8-h or both time points after burn, respectively (all P < 0.05). CONCLUSIONS: The carrier of HES130/0.4 played a crucial role in kidney injury in fluid resuscitation of rats subjected to severe burns. Pyruvate-enriched HES130/0.4 was superior and HES130/0.4, per se, might be not renocytotoxic, but renoprotective. Further studies are warranted.


Assuntos
Injúria Renal Aguda/terapia , Queimaduras/terapia , Portadores de Fármacos/química , Hidratação/métodos , Derivados de Hidroxietil Amido/administração & dosagem , Substâncias Protetoras/administração & dosagem , Ácido Pirúvico/química , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/patologia , Animais , Queimaduras/complicações , Estado Terminal/terapia , Modelos Animais de Doenças , Humanos , Infusões Intravenosas , Soluções Isotônicas/administração & dosagem , Rim/efeitos dos fármacos , Rim/patologia , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
16.
Proc Natl Acad Sci U S A ; 112(17): 5342-7, 2015 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-25870265

RESUMO

We report the surface exploration by the lunar rover Yutu that landed on the young lava flow in the northeastern part of the Mare Imbrium, which is the largest basin on the nearside of the Moon and is filled with several basalt units estimated to date from 3.5 to 2.0 Ga. The onboard lunar penetrating radar conducted a 114-m-long profile, which measured a thickness of ∼5 m of the lunar regolith layer and detected three underlying basalt units at depths of 195, 215, and 345 m. The radar measurements suggest underestimation of the global lunar regolith thickness by other methods and reveal a vast volume of the last volcano eruption. The in situ spectral reflectance and elemental analysis of the lunar soil at the landing site suggest that the young basalt could be derived from an ilmenite-rich mantle reservoir and then assimilated by 10-20% of the last residual melt of the lunar magma ocean.

17.
Am J Emerg Med ; 34(3): 525-30, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26794285

RESUMO

OBJECTIVE: Pyruvate can reduce lipid peroxidation, which plays a critical role in organ injury, in various models. However, it is not fully understood if this inhibition occurs in resuscitation of hemorrhagic shock (HS). This study examines effects of pyruvate Ringer solution (PR) in this respect in rats. METHODS: Rats, subjected to 45% blood loss, were randomly allocated to the 3 groups (n = 18): HS with no fluid resuscitation (group NR), HS resuscitated with lactated Ringer solution (LR) (group LR), and HS resuscitated with PR (group PR). Mean arterial pressure, plasma levels of thiobarbituric acid reactive substances (TBARS), and superoxide dismutase were measured at various time points until 360 minutes after hemorrhage. Visceral organs were harvested at the end for evaluations of the TBARS, antioxidant enzyme, and tissue water content. Other 54 rats with identical procedures without sampling were documented for 24-hour survival rates (n = 18) after fluid resuscitation. RESULTS: Pyruvate Ringer solution significantly increased mean arterial pressure and decreased blood TBARS levels after lethal HS. It also reduced TBARS concentrations and glutathione peroxidase activities but significantly enhanced glutathione reductase activities in most organs and greatly improved the ratios of reduced glutathione over oxidized glutathione in various organs in group PR, compared to group LR. Furthermore, PR significantly improved various organ function and water contents relative to LR. Group PR showed a more than 2-fold higher 24-hour survival rate of group LR. CONCLUSIONS: Pyruvate Ringer solution alleviated organ edema and injury and prompted survival partially through inhibition of lipid peroxidation in various organs in severe HS rats.


Assuntos
Peroxidação de Lipídeos/fisiologia , Insuficiência de Múltiplos Órgãos/terapia , Estresse Oxidativo/efeitos dos fármacos , Ácido Pirúvico/metabolismo , Ressuscitação/métodos , Choque Hemorrágico/terapia , Animais , Soluções Isotônicas/metabolismo , Masculino , Insuficiência de Múltiplos Órgãos/etiologia , Ácido Pirúvico/administração & dosagem , Ratos , Ratos Sprague-Dawley , Solução de Ringer , Choque Hemorrágico/complicações , Análise de Sobrevida
18.
Ophthalmology ; 122(12): 2399-406, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26391463

RESUMO

PURPOSE: To estimate prevalence of visual field (VF) loss in superior and inferior hemifields in binocular VFs in a large sample of patients with bilateral glaucoma. DESIGN: Retrospective cohort study. PARTICIPANTS: Glaucoma patients and suspects attending 4 regionally different secondary-care eye clinics in the United Kingdom. METHODS: Binocular integrated visual fields (IVFs) using a best location method were constructed for 16 642 patients with bilateral VF loss. A significant VF defect was defined as 3 or more VF locations less than a certain sensitivity threshold, such as 20 dB. Patients were classified as having a VF defect in the inferior hemifield, superior hemifield, both hemifields, or neither hemifield. The criteria for number of locations and sensitivity threshold (in decibels) were varied across a large range of values. In addition, factor analysis was applied to the sensitivity values (in decibels) of the IVFs to determine common defect patterns in an automated fashion. MAIN OUTCOME MEASURES: Ratio of patients with binocular VF defects in the superior compared with the inferior areas of the IVF. RESULTS: Estimates of the ratio of patients having binocular VF defects in the superior compared with the inferior region of the IVF ranged from 2.1 (95% confidence interval, 2.1-2.4) to as high as 5.1 (95% confidence interval, 4.7-5.5), depending on the defect criteria used. Fewer than 10% of those patients exhibiting relatively early binocular VF loss had a defect confined to the inferior region only. Common patterns of binocular VF loss were dominated chiefly by superior hemifield defects. CONCLUSIONS: In a clinical population of patients with measurable VF loss in both eyes, superior-only binocular VF loss is more common than inferior-only loss. These estimates, derived from large collections of electronic medical records, are useful for interpreting findings about location of binocular VF loss impacting everyday activities and examining visual disability in glaucoma.


Assuntos
Glaucoma de Ângulo Aberto/diagnóstico , Hemianopsia/diagnóstico , Doenças do Nervo Óptico/diagnóstico , Visão Binocular , Campos Visuais , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pressão Intraocular , Masculino , Estudos Retrospectivos , Limiar Sensorial , Tonometria Ocular , Visão Binocular/fisiologia , Acuidade Visual/fisiologia , Testes de Campo Visual
19.
J Surg Res ; 193(1): 344-54, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25091341

RESUMO

BACKGROUND: Recent findings showed advantages of a novel pyruvate-enriched oral rehydration solution (Pyr-ORS) in resuscitation of burns. This study focused on effects of Pyr-ORS on the visceral blood perfusion (VBP), gastrointestinal function, and survival rate, compared with the bicarbonate-based World Health Organization-guided oral rehydration solution (WHO-ORS), during intragastric rehydration of lethal hemorrhagic shock in rats. METHODS: Sixty adult rats were subjected to 45% total blood volume loss and were randomly allocated to the following three groups (n = 20): group NR (no fluid resuscitation), group PORS (oral Pyr-ORS rehydration), and group BORS (oral WHO-ORS rehydration), respectively. Other 10 rats were served as group NH (the sham group). Enteral rehydration lasted for 4 h after hemorrhage. The mean arterial pressure (MAP), VBP, and plasma enzymes activities of heart, liver, and kidney, and intestinal fatty acid binding protein were measured. Liver, kidney, and ileum were harvested for the evaluation of activities of oxidative enzymes and intestinal barrier protein (ZO-1). Other 84 rats with identical procedures without sampling were observed for their 24-h survival rates. RESULTS: Pyr-ORS was more effective in enhancing the MAP and VBP, inhibiting tissue oxidative damage, and improving organ function, compared with WHO-ORS. Hypoxic lactic acidosis was fully corrected in group PORS in 4 h, whereas it worsened in group BORS, and the 24-h survival rate was twice higher in group PORS than in group BORS (45.8 versus 20.8%, P < 0.05). CONCLUSIONS: A small amount of pyruvate in Pyr-ORS was more therapeutically beneficial than equivalent bicarbonate in WHO-ORS and greatly raised survival in enteral rehydration of lethal hemorrhagic shock. The Pyr-ORS may be an ideal oral fluid in resuscitation of hypovolemic shock, especially in prehospital and resource-poor settings.


Assuntos
Hidratação/métodos , Ácido Pirúvico/farmacologia , Ressuscitação/métodos , Choque Hemorrágico/tratamento farmacológico , Acidose Láctica/tratamento farmacológico , Acidose Láctica/metabolismo , Animais , Bicarbonatos/farmacologia , Modelos Animais de Doenças , Glucose/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Cloreto de Potássio/farmacologia , Distribuição Aleatória , Ratos Sprague-Dawley , Choque Hemorrágico/metabolismo , Cloreto de Sódio/farmacologia , Taxa de Sobrevida , Resultado do Tratamento , Vísceras/irrigação sanguínea
20.
J Surg Res ; 195(1): 89-98, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25619463

RESUMO

BACKGROUND: We have recently proved electroacupuncture (EA) ST36 exerted an anti-inflammatory effect in the early phase of intra-abdominal adhesion formation. Evidences indicate that the anti-inflammatory effect of EA ST36 involves a cholinergic anti-inflammatory pathway-dependent mechanism via the vagus nerve. However, the exact effects and accurate vagal modulation of acupuncture in prevention of postoperative intra-abdominal adhesion formation has not been thoroughly evaluated. MATERIALS AND METHODS: Sprague-Dawley rats subjected to abdominal adhesion lesions operation at the cecum and abdominal wall were randomly divided into six groups as follows: (a) EAN: EA non-channel acupoints; (b) EA: EA ST36 after abdominal lesions; (c) VGX/EA: vagotomy (VGX) after abdominal lesions, then EA ST36; (d) VGX/EAN: VGX after abdominal lesions, then EAN; (e) α-BGT/EA: intraperitoneal injection of α-bungarotoxin (α-BGT, an antagonist of α7 subunit of cholinergic nicotinic receptor) before EA ST36, and (f) α-BGT/EAN group: α-BGT injection before EAN. Seven days after abdominal surgical lesions, the levels of tumor necrosis factor-α (TNF-α) and vascular endothelial growth factor (VEGF) in the adhesive tissue were evaluated, macroscopic observation and histopathologic evaluation of adhesion formation and assessment of angiogenesis by immunohistochemical staining of platelet endothelial cell adhesion molecule-1 (CD31) were performed. RESULTS: EA ST36 reduced TNF-α and VEGF levels in adhesive tissue homogenates 7 d after surgery, whereas vagotomy or intraperitoneal injection of α-BGT before EA ST36 reversed its suppressive effects. EA at non-channel acupoints with or without vagotomy or intraperitoneal injection of α-BGT before EA had no suppressive effects on TNF-α and VEGF levels. EA ST36 alleviated the adhesion formation, with both of macroscopic and histopathologic adhesion scores significantly lower than those of the EAN group (1.56 ± 0.29 versus 3.00 ± 0.82, 1.35 ± 0.4 versus 3.91 ± 0.8, respectively, both P < 0.05). Compared with the EAN group, EA ST36 significantly decreased angiogenesis evidenced by reduced CD31 positive microvessel density in adhesive tissue. CONCLUSIONS: EA ST36 might reduce the postoperative local inflammatory response, attenuate the angiogenesis, and alleviate the adhesion formation partly via activating the cholinergic anti-inflammatory mechanism.


Assuntos
Eletroacupuntura , Aderências Teciduais/prevenção & controle , Técnicas de Fechamento de Ferimentos Abdominais , Animais , Ceco/patologia , Inflamação/metabolismo , Inflamação/prevenção & controle , Masculino , Neovascularização Patológica/metabolismo , Neovascularização Patológica/prevenção & controle , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Distribuição Aleatória , Ratos Sprague-Dawley , Aderências Teciduais/patologia , Fator de Necrose Tumoral alfa/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
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