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1.
Front Cardiovasc Med ; 11: 1348897, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38420263

RESUMO

Introduction: Angiotensin receptor-neprilysin inhibitor (ARNi), comprised of an angiotensin receptor blocker (ARB) and a neprilysin inhibitor (NEPi), has established itself as a safe and effective intervention for hypertension. S086 is a novel ARNi cocrystal developed by Salubris for the treatment of heart failure and hypertension. Methods: Dahl Salt Sensitive (DSS) hypertensive rat model and telemetry system were employed in this study to investigate the anti-hypertensive efficacy of S086 and compare it with the first ARNi-LCZ696. Results and discussion: The study showed that oral administration of S086 dose-dependently lowered blood pressure (P < 0.001). The middle dosage of S086 (23 mg/kg) exhibited efficacy comparable to LCZ696 (68 mg/kg), while also demonstrating superiority at specific time points (P < 0.05). Notably, water consumption slightly decreased post-treatment compared to the vehicle group. Furthermore, there were significant increases in natriuresis and diuresis observed on the first day of treatment with 23 mg/kg and 68 mg/kg S086 (P < 0.001). However, over the course of treatment, the effects in all treatment groups gradually diminished. This study demonstrates the anti-hypertensive efficacy of S086 in DSS hypertensive rat model, offering promising avenues for the clinical development of S086 as a hypertension treatment.

2.
Talanta ; 269: 125458, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38008027

RESUMO

Clustered regularly interspaced short palindromic repeats (CRISPR)/Cas enzymes have been widely applied for biosensor development, combined with various isothermal amplification strategies (IAS) to boost sensitivity and specificity. Currently, the unstable assay and tedious manipulation usually hinder its practical applications. Here, a Cas14a1-advanced LAMP assay (CALA) combined with Rapid Extraction of Bacterial Genomic DNA (REBGD) is proposed for pathogen detection. For rapid CALA, a single stranded fluorescence reporter and ssDNA-gold nanoparticles (AuNPs) are used as signal indicators to establish ultrasensitive and visual platforms. This assay displays precise detection of bacteria, which can achieve an ultrasensitive limit of detection (LOD) 10 aM target genomic DNA. Furthermore, the high reliability of pathogen diagnostic for contrived samples is validated through the rapid visual CALA platform, demonstrating the promising practical testing availability of pathogen detection.


Assuntos
Ouro , Nanopartículas Metálicas , Reprodutibilidade dos Testes , Bioensaio , DNA Bacteriano
3.
J Fungi (Basel) ; 9(5)2023 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-37233307

RESUMO

Soil fungal community characteristics of alpine timberlines are unclear. In this study, soil fungal communities in five vegetation zones across timberlines on the south and north slopes of Sejila Mountain in Tibet, China were investigated. The results show that the alpha diversity of soil fungi was not different between the north- and south-facing timberlines or among the five vegetation zones. Archaeorhizomyces (Ascomycota) was a dominant genus at the south-facing timberline, whereas the ectomycorrhizal genus Russula (Basidiomycota) decreased with decreasing Abies georgei coverage and density at the north-facing timberline. Saprotrophic soil fungi were dominant, but their relative abundance changed little among the vegetation zones at the south timberline, whereas ectomycorrhizal fungi decreased with tree hosts at the north timberline. Soil fungal community characteristics were related to coverage and density, soil pH and ammonium nitrogen at the north timberline, whereas they had no associations with the vegetation and soil factors at the south timberline. In conclusion, timberline and A. georgei presence exerted apparent influences on the soil fungal community structure and function in this study. The findings may enhance our understanding of the distribution of soil fungal communities at the timberlines of Sejila Mountain.

4.
Indian J Pharmacol ; 55(1): 21-26, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36960517

RESUMO

OBJECTIVE: The objective of the study was to compare and observe the therapeutic effect of octreotide and pituitrin in upper gastrointestinal hemorrhage caused by cirrhosis. MATERIALS AND METHODS: In this prospective, randomized, open, single-blind, controlled, and single-center study, patients with upper gastrointestinal hemorrhage induced by cirrhosis were divided into control group (treated with pituitrin) and experimental group (treated with octreotide). The effective time, hemostasis time, and average bleeding volume of the two groups were observed and recorded, and the incidence of adverse reactions, rebleeding rate, and total effective rate of the two groups were compared. RESULTS: One hundred and thirty-two patients with upper gastrointestinal hemorrhage caused by cirrhosis were included from March 2017 to September 2018. By a single-blind method, the patients were randomly divided into control group (n = 66) and experimental group (n = 66). Compared with the control group, the effective time and hemostasis time of the drug were significantly shorter in the experimental group, whereas the average bleeding volume of patients was lower (average P < 0.05). Compare with the control group, the total effective rate was higher in the experimental group, whereas the incidence of adverse reactions was lower (average P < 0.05). During 1-year follow-up, early and late rebleeding rates and hemorrhage-related mortality between the two groups have no difference (average P > 0.05). CONCLUSION: In the treatment of upper gastrointestinal hemorrhage in cirrhosis, octreotide is superior to pituitrin, with advantages of quick onset, short hemostasis time, and less adverse reactions, which is helpful to control the rebleeding rate and bleeding-related mortality.


Assuntos
Octreotida , Hormônios Neuro-Hipofisários , Humanos , Octreotida/uso terapêutico , Método Simples-Cego , Estudos Prospectivos , Hemorragia Gastrointestinal/tratamento farmacológico , Hemorragia Gastrointestinal/etiologia , Cirrose Hepática/complicações , Cirrose Hepática/tratamento farmacológico , Hormônios Neuro-Hipofisários/uso terapêutico , Resultado do Tratamento
5.
J Phys Chem A ; 127(1): 286-299, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36580040

RESUMO

Bio-hybrid fuels are a promising solution to accomplish a carbon-neutral and low-emission future for the transportation sector. Two potential candidates are the heterocyclic acetals 1,3-dioxane (C4H8O2) and 1,3-dioxolane (C3H6O2), which can be produced from the combination of biobased feedstocks, carbon dioxide, and renewable electricity. In this work, comprehensive experimental and numerical investigations of 1,3-dioxane and 1,3-dioxolane were performed to support their application in internal combustion engines. Ignition delay times and laminar flame speeds were measured to reveal the combustion chemistry on the macroscale, while speciation measurements in a jet-stirred reactor and ethylene-based counterflow diffusion flames provided insights into combustion chemistry and pollutant formation on the microscale. Comparing the experimental and numerical data using either available or proposed kinetic models revealed that the combustion chemistry and pollutant formation differ substantially between 1,3-dioxane and 1,3-dioxolane, although their molecular structures are similar. For example, 1,3-dioxane showed higher reactivity in the low-temperature regime (500-800 K), while 1,3-dioxolane addition to ethylene increased polycyclic aromatic hydrocarbons and soot formation in high-temperature (>800 K) counterflow diffusion flames. Reaction pathway analyses were performed to examine and explain the differences between these two bio-hybrid fuels, which originate from the chemical bond dissociation energies in their molecular structures.


Assuntos
Dioxolanos , Poluentes Ambientais , Hidrocarbonetos Policíclicos Aromáticos , Dioxolanos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Dioxanos/análise
6.
Arch Insect Biochem Physiol ; 105(3): e21733, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32895979

RESUMO

This study aimed to determine the relationship between volatile compounds of Picea likiangensis var. linzhiensis cone and host selection of Dioryctria abietella. During the infestation of P. likiangensis var. linzhiensis by D. abietella, their cones and branches emitted volatile compounds, which were extracted using CH2 Cl2 extraction and XAD2 adsorption methods, and were analyzed using gas chromatography-mass spectrometry. Before and after overwintering, D. abietella larva preferred annually infested cones and their extracts, and adult D. abietella preferred to lay eggs on annually infested cones and healthy cones of the year, and the oviposition rate of adult D. abietella was 72% on branches with healthy cones of the year, and no egg was laid on branches with annually healthy cones or branches without cones. The volatile compounds after infestation, α- and ß-pinene, were significantly higher in cones than those in other tissues; however, myrcene in cones was significantly lower than those in other tissues. The annually infested cones produced ß-caryophyllene and (1S)-(-)-ß-pinene, while the annually healthy cones and branches produced myrcene and 3-carene. The annually infested cones and their extracts attracted D. abietella larvae, while that of healthy cones and annually infested cones attracted the adults, indicating that the terpene compounds: α-pinene, ß-pinene, (1S)-(-)-ß-pinene, limonene, and ß-caryophyllene are attractive to D. abietella, and the terpene compounds-myrcene and 3-carene-from the branch tissues may be repulsive to D. abietella.


Assuntos
Mariposas/fisiologia , Picea/química , Compostos Orgânicos Voláteis/química , Animais , Larva/fisiologia , Mariposas/crescimento & desenvolvimento , Oviposição/fisiologia , Picea/parasitologia , Componentes Aéreos da Planta/química
7.
Plant Dis ; 104(8): 2044-2047, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32452717

RESUMO

Colletotrichum asianum is a worldwide plant pathogen causing serious fruit or leaf anthracnose diseases on a variety of plant hosts such as mango, coffee berry, chili, and other potential hosts, and it is distributed widely in Asia, America, Africa, and Oceania. This is the first genome resource available for C. asianum. The draft genome assembly will allow further analysis of species diversity and evolutionary mechanisms, and may serve as a foundation for genetic analysis that leads to greater understanding of interactions between plants and fungal pathogens.


Assuntos
Colletotrichum , Mangifera , Frutas , Doenças das Plantas , Folhas de Planta
8.
Exp Ther Med ; 17(5): 3701-3708, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30988755

RESUMO

Human T-cell leukemia virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia/lymphoma (ATL). Following viral infection with HTLV-1, certain infected cells exhibit clonal proliferation. Additional genetic and epigenetic changes in these clonally proliferating cells provide them with the selective advantage of growth, which eventually results in ATL. The precise mechanism, however, has yet to be completely elucidated. It has previously been established that APOBEC3 enzymes are potent host-antiviral restriction factors. Conversely, previous studies have reported that the A3B level is increased in tumor virus infections, such as those caused by HBV and HPV, suggesting that A3B exerts a function as a mutagen. Therefore, the present study analyzed the expression of APOBEC3 family members in various HTLV-1 infection states. No significant differences were observed in the expression between healthy donors and patients with HTLV-1-associated myelopathy. Although no significant changes in the expressions of A3C, A3D, A3F and A3G between uninfected and HTLV-1-infected mice were observed, an increased A3B expression was observed in a short-term humanized mouse model following HTLV-1 infection. In a long-term humanized mouse model following HTLV-1 infection, the gene expression array data exhibited an apparent increase in A3B and CADM1, which are indicators of ATL. Collectively, the results of the present study suggest that A3B is likely involved in the development of ATL in HTLV-1-infected humanized mice.

9.
Phys Rev E ; 97(1-1): 013103, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29448413

RESUMO

We report an electrohydrodynamic instability in a premixed stagnation flame under manipulations of a dc electric field. This instability occurs when the electric field strength is at a certain value below the breakdown threshold, which is 0.75 kV/cm in the experimental setup. Above this value the flame front suddenly transits from a substrate-stabilized near-flat shape to a nozzle-stabilized conical surface, accompanied by a jump in the electric current through the flame field. At the transition moment, the flame spontaneously propagates upstream to the nozzle while the flow velocity at the upstream of the flame front decreases to zero, as revealed by high-speed photographs and PIV measurements. These phenomena indicate a transient balance between the fluid inertia and the electric body force around the instability threshold. A quantitative model suggests that the flame instability can be explained by a positive feedback loop, where the electric field applies a nonuniform electric body force, pulling the flame front upstream, and the pulled flame front in turn enhances the local electric body force. The electrohydrodynamic instability occurs when the electric pulling is strong enough and both the growth rates and the magnitudes of the electric body force on flame exceed those of the fluid dynamic pressure.

10.
J Chem Phys ; 147(24): 244305, 2017 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-29289134

RESUMO

Physical dimerization of polycyclic aromatic hydrocarbons (PAHs) has been investigated via molecular dynamics (MD) simulation with the ReaxFF reactive force field that is developed to bridge the gap between the quantum mechanism and classical MD. Dynamics and kinetics of homo-molecular PAH collision under different temperatures, impact parameters, and orientations are studied at an atomic level, which is of great value to understand and model the PAH dimerization. In the collision process, the enhancement factors of homo-molecular dimerizations are quantified and found to be larger at lower temperatures or with smaller PAH instead of size independent. Within the capture radius, the lifetime of the formed PAH dimer decreases as the impact parameter increases. Temperature and PAH characteristic dependent forward and reverse rate constants of homo-molecular PAH dimerization are derived from MD simulations, on the basis of which a reversible model is developed. This model can predict the tendency of PAH dimerization as validated by pyrene dimerization experiments [H. Sabbah et al., J. Phys. Chem. Lett. 1(19), 2962 (2010)]. Results from this study indicate that the physical dimerization cannot be an important source under the typical flame temperatures and PAH concentrations, which implies a more significant role played by the chemical route.

11.
Phys Rev Lett ; 114(9): 093401, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25793812

RESUMO

The absorption-ablation-excitation mechanism in laser-cluster interactions is investigated by measuring Rayleigh scattering of aerosol clusters along with atomic emission from phase-selective laser-induced breakdown spectroscopy. For 532 nm excitation, as the laser intensity increases beyond 0.16 GW/cm^{2}, the scattering cross section of TiO_{2} clusters begins to decrease, concurrent with the onset of atomic emission of Ti, indicating a scattering-to-ablation transition and the formation of nanoplasmas. With 1064 nm laser excitation, the atomic emissions are more than one order of magnitude weaker than that at 532 nm, indicating that the thermal effect is not the main mechanism. To better clarify the process, time-resolved measurements of scattering signals are examined for different excitation laser intensities. For increasing laser intensity, the cross section of clusters decreases during a single pulse, evincing the shorter ablation delay time and larger ratios of ablation clusters. Assessment of the electron energy distribution during the ablation process is conducted by nondimensionalizing the Fokker-Planck equation, with analogous Strouhal Sl_{E}, Peclet Pe_{E}, and Damköhler Da_{E} numbers defined to characterize the laser-induced aerothermochemical environment. For conditions where Sl_{E}≫1, Pe_{E}≫1, and Da_{E}≪1, the electrons are excited to the conduction band by two-photon absorption, then relax to the bottom of the conduction band by electron energy loss to the lattice, and finally serve as the energy transfer media between laser field and lattice. The relationship between delay time and excitation intensity is well correlated by this simplified model with quasisteady assumption.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(11): 2980-3, 2009 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-20101968

RESUMO

FT-Raman and surface enhanced Raman spectra (SERS) of norfloxacin and norfloxacin capsule on the silver colloidal substrate were recorded, and the vibrational and enhanced peaks were assigned; interactions of norfloxacin and DNA were researched. The experimental results proved that the characteristic vibrations of capsule's content and NFX standard, which is v(C-F), vs(O-C-O), v(C=C), did not change, while the changes in molecular skeleton's vibrations were substantial. Additives do not affect the Raman spectroscopy of norfloxacin substantively. An analytical method for detecting norfloxacin medcine can be established by FT-Raman. Without any ions, the interaction is mainly caused by the inserting-action mode between the ring of norfloxacin and the double helix structure of DNA, and norfloxacin could interact with DNA directly, providing reliable evidence for antibacterial mechanism of quinoxalone antibiotics.


Assuntos
DNA/química , Norfloxacino/química , Análise Espectral Raman
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