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1.
Gen Physiol Biophys ; 43(1): 1-11, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38312030

RESUMO

To investigate the potential functions and regulatory mechanism of circRSU1 on septic acute lung injury (sepsis-ALI) progression. We used lipopolysaccharide (LPS)-stimulated human pulmonary microvascular endothelial cells (HPMECs) to establish the cell model of sepsis-ALI in vitro. qRT-PCR and Western blotting were used for the detection of genes and proteins. The migration and tubulogenesis of HPMECs were assessed by transwell, wound healing, and tube formation assays. Inflammatory factors were detected by ELISA analysis. Cell permeability (PA) was determined by transendothelial resistance (TEER) and fluorescein isothiocyanate (FITC) with transwell assay. The interaction between miR-1224-5p and circRSU1 or ITGA5 (Integrin Subunit Alpha 5) was studied by dual-luciferase reporter and RNA pull-down assays. CircRSU1 expression was decreased after LPS treatment in HPMECs. Functionally, re-expression of circRSU1 in HPMECs could alleviate LPS-induced inflammatory response, the inhibition of cell migration and tube formation and enhancement of cell permeability. Mechanistically, circRSU1 acted as a sponge for miR-1224-5p. LPS treatment enhanced miR-1224-5p expression, and inhibition of miR-1224-5p reversed LPS-evoked HPMEC dysfunction mentioned above. Moreover, miR-1224-5p could abolish the protective effects of circRSU1 on HPMECs. In addition, miR-1224-5p directly targeted ITGA5, and circRSU1 was able to regulate ITGA5 expression via interacting with miR-1224-5p. CircRSU1 could alleviate LPS-induced HPMEC injury by miR-1224-5p/ITGA5 axis, indicating the potential molecular contribution of circRSU1 in sepsis-ALI.


Assuntos
Lesão Pulmonar Aguda , MicroRNAs , RNA Circular , Sepse , Humanos , Lesão Pulmonar Aguda/induzido quimicamente , Apoptose , Células Endoteliais , Lipopolissacarídeos , MicroRNAs/genética , RNA Circular/genética
2.
Int J Mol Sci ; 24(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36769364

RESUMO

Hydrodenitrogenation (HDN) experiments and density functional theory (DFT) calculations were combined herein to study the substituent effects of the nitrogen heterocycle on the HDN behaviors of indole and quinoline. Indole (IND), 2-methyl-indole (2-M-IND), 3-methyl-indole (3-M-IND), quinoline (QL), 2-methyl-quinoline (2-M-QL) and 3-methyl-quinoline (3-M-QL) were used as the HDN reactant on the NiMo/γ-Al2O3 catalyst. Some key elementary reactions in the HDN process of these nitrogen compounds on the Ni-Mo-S active nanocluster were calculated. The notable difference between IND and QL in the HDN is that dihydro-indole (DHI) can directly convert to O-ethyl aniline via the C-N bond cleavage, whereas tetrahydro-quinoline (THQ) can only break the C-N single bond via the full hydrogenation saturation of the aromatic ring. The reason for this is that the -NH and C=C groups of DHI can be coplanar and well adsorbed on the Ni-Mo-edge simultaneously during the C-N bond cleavage. In comparison, those of THQ cannot stably simultaneously adsorb on the Ni-Mo-edge because of the non-coplanarity. Whenever the methyl group locates on the α-C or the ß-C atom of indole, the hydrogenation ability of the nitrogen heterocycle will be evidently weakened because the methyl group increases the space requirement of the sp3 carbon, and the impaction of the C=C groups on the Ni-S-edge cannot provide enough space. When the methyl groups are located on the α-C of quinoline, the self-HDN behavior of 2-M-QL is similar to quinoline, whereas the competitive HDN ability of 2-M-QL in the homologs is evidently weakened because the methyl group on the α-C hinders the contact between the N atom of 2-M-QL and the exposed metal atom of the coordinatively unsaturated active sites (CUS). When the methyl group locates on the ß-C of quinoline, the C-N bond cleavage of 3-methyl-quinoline becomes more difficult because the methyl group on the ß-C increases the steric hindrance of the C=C group. However, the competitive HDN ability of 3-M-QL is not evidently influenced because the methyl group on the ß-C does not evidently hinder the adsorption of 3-M-QL on the active sites.


Assuntos
Nitrogênio , Quinolinas , Hidrogenação , Modelos Teóricos , Indóis/química
3.
Int J Biometeorol ; 66(9): 1787-1796, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35918554

RESUMO

The dysregulation in heat balance, the main cause of exertional heat stroke, occurs not only in midsummer but also in the cold season. Possible causes of this are a reduction in convection and evaporation due to tailwinds and an acceleration of radiant heat inflow. Although the amount of radiant heat that reaches the surface can be estimated, the actual amount of heat that flows into the body cannot be specified yet. This paper made an experimental attempt at this. A device is made up of a temperature controllable heat sink and heat flow detector, which keeps the surface temperature constant and has a heat exchange coefficient comparable to that of the human body surface. The output of this device (total heat exchange) was divided into radiant heat exchange and other heat exchange using a standard radiant heat calibrator, Leslie cube. A phenomenon, in which a wet surface while the surface temperature was low absorbed larger heat than that of the dry surface, was found. And authors named this "hidden heat inflow". As a result of multiple regression analyses, both radiant heat exchange and other heat exchanges are closely related to the surface temperature, and the maximum difference in total heat exchange during the experiment reached 200 kcal/m2/h. It has been suggested that this phenomenon may also occur on the surface of human skin. One of the causes of this "hidden heat inflow" is considered to be the decrease in evaporative cooling due to the decrease in surface temperature. However, this alone cannot explain all of the phenomena, so water vapor aggregation may also be involved. A "hidden heat inflow" as a sufficient heat source for exertional heat stroke or collapse during a marathon race on a cold day was evidenced experimentally.


Assuntos
Golpe de Calor , Temperatura Alta , Temperatura Corporal , Regulação da Temperatura Corporal , Humanos , Temperatura
4.
Biomed Rep ; 16(2): 14, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35070298

RESUMO

The application of next-generation sequencing (NGS) in routine clinical analysis is still limited. The significance of NGS in the identification of pathogens of lower respiratory tract infection should be assessed as part of routine clinical bacterial examinations and chest imaging results. In the present study, the alveolar lavage fluid samples of 30 patients (25 males and 5 females, aged 19-92 years old, with a median age of 62) were examined by routine bacterial culture and NGS, and the results of pathogen detection and identification were compared. Chest imaging showed consolidation in all 30 patients (100%), and pleural effusion in 13 of the 30 patients (43.33%). The routine bacterial culture of the lavage solution was only positive in 14 of the 30 patients (46.6%), and negative in 16 patients (53.33%). However, the positive rate of NGS test results of the lavage fluid was 100%. A total of 12 cases (40%) were completely consistent with the routine bacterial culture test, with 56 other pathogens of mixed infection detected, accounting for the short comings of the routine bacterial examination. Although NGS cannot distinguish between live and dead bacteria, it is still a useful detection technology for accurate diagnosis of clinical infectious diseases. It is worthy of adaptation in the clinic for more effective clinical management and treatment of the lower respiratory airway infection in addition to the routine bacterial culture testing.

5.
Langmuir ; 37(47): 13941-13951, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34780183

RESUMO

High-voltage spinel materials have attracted widespread attention because of their advantages such as good rate performance, low cost, abundant source, and easy preparation. However, the Mn dissolution and Jahn-Teller effect of spinel materials during cycling limit their practical application. In this paper, the allogenic composites (1 - x)Li(Ni0.2Co0.1Mn0.7)2 O4·xLi1.2(Ni0.2Co0.1Mn0.7)0.8O2 (x = 0.05, 0.1, 0.2, 0.3, 0.4, and 0.5) are developed by the carbonate co-precipitation method combined with the high-temperature sintering method, which are certified by the X-ray diffraction (XRD) spectrum and transmission electron microscopy (TEM) image. The results show that the lithium-rich phase of the allogenic composites can effectively improve the initial discharge capacity, alleviate the side reaction between the spinel material and the electrolyte, and improve the cycle stability. This work reveals the relationship between the structure and electrochemical performance of the in situ transformed spinel@Li-rich allogenic composites and provide a new clue to design a high-performance spinel cathode for advanced Li-ion batteries.

6.
RSC Adv ; 9(21): 11951-11959, 2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35517022

RESUMO

Recent results have evidenced that carbon plays an important role in stabilizing the structure of the active phase in catalysts. In this work, carbon-coated alumina was prepared by applying polydopamine (PDA) as a sacrificial carbon source to modify the surface properties of γ-alumina, which then was used as a support to prepare supported NiMo catalysts for hydrodesulfurization (HDS) of dibenzothiophene (DBT). NiMo/Al2O3 catalysts exhibited limited hydrodesulfurization performances due to their strong metal-support interaction. Herein, we report an unexpected phenomenon that sacrificial carbon layers can be constructed on the surface of the Al2O3 support from the carbonization of polydopamine (PDA) and mediated the interaction between the active site and support. Through the removal of carbon layers and sulfidation, the resulting NiMo catalysts exhibit excellent performance for HDS reaction of dibenzothiophene (DBT), which is associated with adequate loading of residual carbon species, leading to an enhanced amount of active species under sulfidation conditions. Moreover, the facile synthetic strategy can be extended to the stabilization of the active phase on a broad range of supports, providing a general approach for improving the metal-support interaction supported nanocatalysts.

7.
Planta ; 232(4): 873-86, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20632186

RESUMO

Promoters from an ACC oxidase gene (PtACO1) and its nearly identical paralog (NIP) (PtACO2) of loblolly pine (Pinus taeda L.) were recovered from genomic DNA using PCR amplification. Transgenic Arabidopsis plants harboring genetic constructs from which beta-glucuronidase (GUS) expression was driven by the full-length (pACO1:GUS, pACO2:GUS) or truncated (pACO1-1.2:GUS, pACO2-1.2:GUS) loblolly pine ACC oxidase gene promoters displayed distinctive patterns of expression for the different promoter constructs. Both full-length promoter constructs, but not those using truncated promoters, responded to indole-3-acetic acid (IAA) and wounding. Both pACO1:GUS and pACO1-1.2:GUS responded to pathogen attack, while neither version of the pACO2 promoter responded to infection. In the inflorescence stalks, the full-length pACO1 promoter construct, but not the truncated pACO1-1.2:GUS or either pACO2 construct, responded to bending stress. When flowering transgenic Arabidopsis plants were placed in a horizontal position for 48 h, expression from pACO2:GUS, but not the other constructs, was induced on the underside of shoots undergoing gravitropic reorientation. The expression pattern for the pACO2:GUS construct in transgenic Arabidopsis was consistent with what might be expected for a gene promoter involved in the compression wood response in loblolly pine. Although near complete sequence identity between PtACO1 and PtACO2 transcripts prevented quantitation of specific gene products, the promoter expression analyses presented in this study provide strong evidence that the two ACC oxidase genes are likely differentially expressed and responded to different external stimuli in pine. These results are discussed with respect to the potential functional differences between these two genes in loblolly pine.


Assuntos
Aminoácido Oxirredutases/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Pinus taeda/enzimologia , Pinus taeda/genética , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/metabolismo , Regiões Promotoras Genéticas/genética , Aminoácido Oxirredutases/genética , Arabidopsis/genética , Arabidopsis/microbiologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , Ácidos Indolacéticos/farmacologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/microbiologia
8.
Fundam Clin Pharmacol ; 23(2): 189-96, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19298236

RESUMO

To study the releasing properties and tissue-targeting characteristics of methotrexate-loaded red blood cells (MTX-RBCs), pharmacokinetics and tissue distributions of intravenous injected MTX-RBCs and free MTX were compared. MTX-RBCs were made from rat erythrocytes using a hypertonic method. After i.v. injection of MTX-RBCs or free MTX to rats, both plasma and tissue homogenate samples at each time-point were collected and analyzed by RP-HPLC. From this data, pharmacokinetic parameters and tissue distributions of MTX were obtained. MTX-RBCs were successfully produced by the hypertonic method. After i.v. injection, MTX-RBCs displayed more than three times longer half-life and MRT than free MTX, and the velocity of MTX clearance from plasma was much slower. The ratio of area under the concentration time curve (AUC)(tissue) to AUC(plasma) in the liver was clearly higher than that for other organs after MTX-RBCs administration; MRT in the liver was also longer. This study has demonstrated that the hypertonic method for making MTX-RBCs has led to a preparation with slow release properties as well as liver-targeting characteristics in rats. This approach offers considerable potential for the treatment of tumors in liver, which would merit further investigation.


Assuntos
Antimetabólitos Antineoplásicos/farmacocinética , Portadores de Fármacos/química , Eritrócitos/química , Metotrexato/farmacocinética , Animais , Antimetabólitos Antineoplásicos/administração & dosagem , Área Sob a Curva , Cromatografia Líquida de Alta Pressão , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos , Meia-Vida , Injeções Intravenosas , Fígado/metabolismo , Masculino , Metotrexato/administração & dosagem , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
9.
Clin Exp Pharmacol Physiol ; 33(11): 1066-72, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17042916

RESUMO

1. The Aim Of The Present Study Was To Test The Efficacy Of The Novel Endothelin (Et) Receptor Antagonist CPU0507 In Treating Rat Hypoxic Pulmonary Hypertension (Ph) In Vivo And In Vitro And To Explore The Role Of The Et-1 System In The Disease. 2. Male Sprague-dawley Rats (220 +/- 20 G) Were Divided Into Four Groups: (I) Control; (Ii) Untreated Hypoxic (28 Days Hypoxia); (Iii) Hypoxic Rats Treated In The Last 5 Days Of Hypoxia With Nifedipine(5 Mg/kg Per Day, P.o.); And (Iv) Hypoxic Rats Treated In The Last 5 Days Of Hypoxia With CPU0507 (20 Mg/kg Per Day, S.c.). Effects Of Treatments On Haemodynamics And Biochemical Data, As Well As Functional Assessments Of The Isolated Pulmonary Artery, Were Determined In Vivo And In Vitro. 3. It Was Found That CPU0507 Reduced The Elevated Pulmonary Arterial Pressure And Right Heart Weight Index And Restored Abnormalities In Nitric Oxide (No), Malondialdehyde And No Synthase (Nos) In The Serum And Superoxide Dismutase, Hydroxyproline And Nos In Pulmonary Homogenates. In Addition, CPU0507 Restored Altered Pulmonary Vasoconstrictor And Vasodilator Responses. Vascular Constriction And Dilatation Of Untreated Pulmonary Arteries Were Reverted Effectively Towards Normal Following Exposure Of Artery Rings To CPU0507 In Vitro. 4. In Conclusion, The Results Indicate That Hypoxic Ph Is Relieved Significantly By CPU0507 In Vivo And In Vitro And The Effects Are Presumed To Be Mediated By Suppression Of The Et-reactive Oxygen Species Axis.


Assuntos
Antagonistas dos Receptores de Endotelina , Hipertensão Pulmonar/tratamento farmacológico , Artéria Pulmonar/efeitos dos fármacos , Tiadiazóis/farmacologia , Vasoconstrição/efeitos dos fármacos , Animais , Anti-Hipertensivos/farmacologia , Coração/efeitos dos fármacos , Hipóxia , Masculino , Estrutura Molecular , Miocárdio/patologia , Nifedipino/farmacologia , Ratos , Ratos Sprague-Dawley , Tiadiazóis/química , Vasodilatação/efeitos dos fármacos
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