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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.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(1): 24-34, 2020 Jan 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-32132294

RESUMO

OBJECTIVES: To examine the changes of coenzyme Q10 (CoQ10) and ß1,3-galactosyl transferase specific chaperone 1 (C1GALT1C1) in brain of rats with ischemic injury at different time points and to explore the protective mechanism of ultrashort wave (USW) on ischemic brain injury. METHODS: Fifty SD rats were randomly divided into 5 groups (n=10 per group): a sham group (control group) and 4 experimental group (ischemia for 2 h). The 4 experimental groups were set as a model 1 d group, a USW 1 d group, a model 3 d group and a USW 3 d group, respectively. Five rats were randomly selected for 2,3,5-triphenyltetrazoliumchloride (TTC) staining in each experimental group, and the remaining 5 rats were subjected to Western blotting and real-time PCR. The percentage of cerebral infarction volume and the relative expression level of CoQ10 and C1GALT1C1 in the brain were examined and compared. RESULTS: The infarct volume percentage after TTC staining was zero in the sham group. With the progress of disease and USW therapy, the infarct volume percentage was decreased in the experimental groups (all P<0.05); Western blotting and real-time PCR showed that the relative expression level of CoQ10 in the sham group was the highest, while in the experimental groups, the content of CoQ10 showed a upward trend with the extension of disease and USW therapy, with significant difference (all P<0.05). The relative expression level of C1GALT1C1 in the sham group was the lowest, but in the experimental groups, they showed a downward trend with the extension of disease and USW therapy, with significant difference (all P<0.05). CONCLUSIONS: Non-caloric USW therapy may upregulate the expression of CoQ10 to suppress the expression of C1GALT1C1 in rats, leading to alleviating cerebral ischemic reperfusion injury.


Assuntos
Isquemia Encefálica , Traumatismo por Reperfusão , Animais , Encéfalo , Chaperonas Moleculares , Ratos , Ratos Sprague-Dawley , Ubiquinona/análogos & derivados
3.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38564327

RESUMO

The assessment of the concentration and distribution of l6N, derived from 16O in the cooling water exposed to neutron irradiation, is essential for ensuring radiation safety during nuclear reactor operation. The imaging method allows for the visualization of the intensity distribution of these l6N by capturing gamma-rays emitted during their decay process. However, the existing gamma camera is exclusively compatible with gamma-rays below 2 MeV. In this paper, a novel gamma camera featuring a thick double-conical penumbra aperture, a pixelated Lu1.8Y0.2SiO5:Ce scintillator array, and a position-sensitive photomultiplier tube is proposed to address this limitation. This innovative design offers a large field of view (FOV) and is suitable for high energy extended gamma source imaging. The optimization of key parameters of the camera was conducted, and a FOV of 60° and an angular resolution of up to 4.57° were achieved. Imaging simulations, including a simplified model of the primary loop of the pressurized-water reactor by GEANT4 code and image reconstruction using the expectation maximum algorithm, demonstrated that the proposed gamma camera could obtain a satisfactory spatial resolution for diagnosing the distribution of 16N in the primary loop of a nuclear reactor.

4.
Adv Clin Exp Med ; 32(11): 1265-1277, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37191448

RESUMO

BACKGROUND: Diabetic kidney disease (DKD) is closely related to autophagy and inflammation. The mTOR/unc-51 like autophagy activating kinase 1 (ULK1) signaling axis is involved in the regulation of autophagy. Ultrashort wave (USW) therapy has been extensively studied in inflammatory diseases. However, the therapeutic effect of USW on DKD and the role of the mTOR/ULK1 signaling axis in USW interventions remain uncertain. OBJECTIVES: This study aimed to explore the therapeutic effects of USW on DKD rats and the role of the mTOR/ULK1 signaling axis in USW interventions. MATERIAL AND METHODS: A DKD rat model was established using a high-fat diet (HFD)/sugar diet and streptozocin (STZ) induction. The optimal duration of USW intervention was determined using different USW treatments. The levels of metabolism, inflammation and fibrosis associated with kidney injury in rats were measured. Western blot analysis was performed on the related indexes of autophagy and the mTOR/ULK1 signaling axis. RESULTS: In DKD rats, microalbuminuria (MAU), glucose (GLU), creatinine (CRE), and blood urea nitrogen (BUN) levels decreased after the USW intervention. Levels of interleukin (IL)-1ß, inducible nitric oxide synthase (iNOS), immunoglobulin M (IgM), immunoglobulin G (IgG), IL-18, tumor necrosis factor alpha (TNF-α), and IL-6 decreased in the USW group compared to the model group. The IL-10 and arginase (Arg-1) levels were increased in the USW group. The content of fibrosis-related indexes (vascular endothelial growth factor (VEGF), fibronectin (FN), type IV collagen, and type I collagen) decreased in the urine of the DKD rats. After USW treatment, LC3B and Beclin1 levels increased, while the level of p62 decreased. The levels of nephrin, podocin and synaptopodin increased. Ultrashort wave could reduce p-mTOR/mTOR ratios and increase ULK1 expression. After the overexpression of ULK1, the levels of LC3B and Beclin1 were higher in the overexpression (oe)-ULK1 group than in the oe-negative control (NC) group, while the level of p62 decreased. After mTOR activation, LC3B and ULK1 expression decreased, while CRE, BUN, MAU, and GLU levels increased. CONCLUSIONS: Ultrashort wave alleviated kidney injury induced by the HFD/sugar diet and STZ. The USW intervention reversed the decreased autophagy levels in the DKD rats. The mTOR/ULK1 signaling axis mediated USW to promote autophagy.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Ratos , Animais , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/prevenção & controle , Proteína Beclina-1/farmacologia , Fator A de Crescimento do Endotélio Vascular , Serina-Treonina Quinases TOR/metabolismo , Inflamação , Autofagia , Fibrose , Açúcares/farmacologia , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo
5.
Rev Sci Instrum ; 93(4): 043104, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35489950

RESUMO

The uncertainties of spot size and position need to be clarified for x-ray sources as they can affect the detecting precision of the x-ray probe beam in applications such as radiography. In particular, for laser-driven x-ray sources, they would be more significant as they influence the inevitable fluctuation of the driving laser pulses. Here, we have employed the penumberal coded aperture imaging technique to diagnose the two-dimensional spatial distribution of an x-ray emission source spot generated from a Cu solid target irradiated by an intense laser pulse. Taking advantage of the high detection efficiency and high spatial resolution of this technique, the x-ray source spot is characterized with a relative error of ∼5% in the full width at half maximum of the intensity profile in a single-shot mode for general laser parameters, which makes it possible to reveal the information of the unfixed spot size and position precisely. Our results show the necessity and feasibility of monitoring the spot of these novel laser-driven x-ray sources via the penumbral coded aperture imaging technique.

6.
Appl Radiat Isot ; 166: 109299, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32911439

RESUMO

The work aimed to calculate the radiation biological shielding performance of particle reinforced metal matrix composite (PRMMCs) using more reasonable model instead of conventional Uniform Filling Model, also attempted to provide a basis for the radiation shielding optimal design of such materials. Firstly, RSA (Random Sequential Adsorption) Model and GRM (Grid Random Model) were established based on MATLAB and Monte Carlo Particle transport program MCNP, and then advantages and disadvantages of them were compared. Later, the influences of metal matrix type, particle (B4C) content, particle shape and particle shape parameters on the biological shielding performance of materials were calculated under different energy neutrons and different thickness shield using random models. Finally, the optimal aspect ratio of regular hexahedral B4C was calculated by Genetic Algorithm combined with MATLAB and MCNP. It indicated that GRM could be applied to radiation shielding calculation of PRMMCs.

7.
J Microbiol Methods ; 86(1): 78-81, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21473889

RESUMO

Detection and identification of bacterial etiology in urine is critical for accurate diagnosis and subsequent rational treatment of urinary tract infections (UTIs). Urine culture followed by a series of biochemical reactions is currently the standard method for detecting and distinguishing microorganisms associated with UTIs. The whole procedure commonly takes more than 24h. Here we developed a new system combining 16S rRNA gene broad-range PCR with pyrosequencing technology that allows for bacteria detection and identification in urine in 5h. To evaluate this system for rapid diagnosis of bacteriuria, 768 urine specimens were collected from patients with suspected UTIs and were tested side-by-side using standard urine culture-based identification method and the pyrosequencing method. The results from pyrosequencing correlated well with those from traditional culture-based identification method. The overall agreement between these two methods reached 98.0% (753/768). In addition, we tested the sensitivity of pyrosequencing method and determined that urine bacterial numbers as low as 10(4)cfu/ml could be accurately detected and identified. In conclusion, compared with traditional biochemical method, the PCR-pyrosequencing system significantly improved the detection and identification of bacteriuria with shorter time, higher accuracy, and higher throughput, thus allowing earlier pathogen-adapted antibiotic therapy for patients.


Assuntos
Bactérias/isolamento & purificação , Análise de Sequência de DNA/métodos , Infecções Urinárias/diagnóstico , Infecções Urinárias/microbiologia , Urina/microbiologia , Bactérias/classificação , Bactérias/genética , Humanos
8.
Oncol Rep ; 25(2): 503-11, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21152870

RESUMO

Protease-activated receptor 2 (PAR2) is a G-protein-coupled receptor and its activation has been associated with the pathogenetic progress in certain cancers. Toll-like receptor 4 (TLR4), one member of Toll-like receptors family, is mainly contributed to the innate immune response. However, recent studies have shown that TLR4 is aberrantly expressed in various types of carcinomas and may correlate with tumor progression. Previously, we reported that PAR2 could be expressed in human colon cancer cell line (SW620) and its activation by some stimulants was able to facilitate cell proliferation and migration. In our recent preliminary experiment, it was found that SW620 cells also had TLR4 expression. Thus, we considered that PAR2 and TLR4 could have some collaborative roles in SW620 cells. In the current study, the cross-inducible expression of PAR2 and TLR4 on SW620 cells was investigated, and the functional roles of their activation on the behavior of SW620 cells were evaluated. It was found that activation of PAR2 with PAR2-AP (PAR2 agonist, 100 µM) enhanced TLR4 releasement and vice versa. The activation of PAR2 or TLR4 (with LPS, 100 ng/ml) could promote SW620 cell proliferation and migration, and the phosphorylation of ERK1/2 but not p38MAPK, as well as the expression of interleukin 8 (IL-8) and tissue factor (TF). Whereas the caspase-7 expression was decreased under PAR2 or TLR4 activation. Furthermore, ERK1/2 inhibitor (U0126, at 10 µM) could intervene in all regulating effects of PAR2 or/and TLR4. Collectively, this study demonstrated that both PAR2 and TLR4 activation on SW620 cells can trigger the phosphorylation of ERK1/2, regulate the expression of IL-8, TF and caspase-7, thereby promote the proliferation and migration of cells.


Assuntos
Carcinoma/patologia , Neoplasias do Colo/patologia , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Receptor PAR-2/agonistas , Receptor 4 Toll-Like/agonistas , Carcinoma/genética , Carcinoma/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lipopolissacarídeos/farmacologia , Proteína Quinase 3 Ativada por Mitógeno/fisiologia , Oligopeptídeos/farmacologia , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Receptor Cross-Talk/efeitos dos fármacos , Receptor Cross-Talk/fisiologia , Receptor PAR-2/genética , Receptor PAR-2/metabolismo , Receptor PAR-2/fisiologia , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Receptor 4 Toll-Like/fisiologia , Regulação para Cima/efeitos dos fármacos
9.
Int J Mol Med ; 24(4): 557-62, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19724897

RESUMO

Growing evidence suggests that autoantibodies directly contribute to hypercoagulability in the antiphospholipid syndrome (APS). One proposed mechanism is the antibody-induced expression of tissue factor (TF) by blood monocytes. Annexin A2 (ANX2), a mediator of cell surface-specific plasmin generation, was identified to mediate endothelial cell activation by anti-beta2-glycoprotein I (anti-beta 2 GPI) antibody. Our previous study suggested that ANX2 was also involved in anti-beta 2 GPI/beta 2 GPI-induced TF expression on monocytes. In the current study, it was further demonstrated that beta 2 GPI interacts with ANX2 not only in a cell-dependent form but also in a cell-free system. To further confirm the effects of ANX2 on anti-beta 2 GPI/beta 2 GPI-induced TF expression, an ANX2 cDNA-containing vector was transfected into HEK 293T cells which had originally little ANX2, then cells were treated by anti-beta 2 GPI/beta 2 GPI complex. It was found that transfected HEK 293T cells could express more TF both at mRNA and protein levels than that of no-transfected cells. On the other hand, the TF expression was dramatically decreased in the THP-1 cells in which the ANX2 RNA interference was performed. In conclusion, these results indicate that ANX2 on cell surface functions as a mediator boosting TF expression on monocytes induced by anti-beta 2 GPI/beta 2 GPI complex, which is contributed to the thrombotic events in APS.


Assuntos
Anexina A2/fisiologia , Complexo Antígeno-Anticorpo/farmacologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Tromboplastina/metabolismo , beta 2-Glicoproteína I/imunologia , beta 2-Glicoproteína I/metabolismo , Anexina A2/genética , Linhagem Celular , Expressão Gênica/efeitos dos fármacos , Humanos , Tromboplastina/genética
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