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1.
Opt Lett ; 45(10): 2874-2877, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32412490

RESUMEN

A series of theoretical and experimental results has proved that harmonics below/above the band gap are produced mainly by the intraband current/interband polarization for solids in strong mid-infrared laser pulses. However, which mechanism dominates the harmonic process is still debated. In this work, based on simulating high-order-harmonic generation from an MgO crystal in a linearly polarized mid-infrared laser by solving semiconductor Bloch equations, we demonstrate that harmonics just below the band gap originate from the interference between intraband and interband currents. Furthermore, it is found that intensities of harmonics just below the band gap are apparently enhanced with an increase in the incident laser's strength. By analyzing the band dispersion and the transition dipole moment of the 001-cut MgO crystal, this can be attributed to the interband polarization between two conduction bands.

2.
Int J Syst Evol Microbiol ; 70(1): 65-70, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31517595

RESUMEN

A Gram-stain-negative, strictly aerobic, catalase-positive and oxidase-positive bacterium, designated strain YIM MLB12T, was isolated from estuary sediment sampled at Maliao River where it flows into a plateau lake (Dianchi) in Yunnan, south-west PR China. Cells were non-motile and rod-shaped. Growth was observed at 15-35 °C (optimum, 25-30 °C), pH 6.0-10.0 (optimum, pH 7.0-8.0) and in the presence of 0-7 % (w/v) NaCl (optimum, 0.5-2 %). Results of phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM MLB12T formed a tight phylogenic lineage with members of the genus Lampropedia and was closely related to 'Lampropedia puyangensis' 2-bin with 98.3 % sequence similarity and had low similarities to the type strains of Lampropediahyalina ATCC 11041T (96 %) and Lampropedia cohaerens CT6T (95.5 %). Average nucleotide identity and in silico DNA-DNA hybridization values between strain YIM MLB12T and 'L. puyangensis' KCTC 32235 were 76.5 and 22.6 %, respectively. Strain YIM MLB12T contained ubiquinone-8 as the major quinone. The predominant cellular fatty acids were summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), C16 : 0, C10 : 0 3-OH, summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c), C12 : 0 3-OH and C14 : 0. The polar lipid profile of strain YIM MLB12T was composed predominantly of diphosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine and phosphatidylglycerol. The major polyamine was spermidine. The genomic DNA G+C content of strain YIM MLB12T was 56.8 mol%. Based on its genotypic and chemotaxonomic features and results of phenotypic analyses, strain YIM MLB12T represents a novel species of the genus Lampropedia, for which the name Lampropediaaestuarii sp. nov. is proposed. The type strain is YIM MLB12T (=KCTC 42886T=CGMCC 1.17071T).


Asunto(s)
Comamonadaceae/clasificación , Estuarios , Filogenia , Ríos/microbiología , Microbiología del Agua , Técnicas de Tipificación Bacteriana , Composición de Base , China , Comamonadaceae/aislamiento & purificación , ADN Bacteriano/genética , Ácidos Grasos/química , Sedimentos Geológicos/microbiología , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Espermidina/química , Ubiquinona/química
3.
Opt Express ; 27(23): 34392-34404, 2019 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-31878487

RESUMEN

Band structure and transition dipole moment play important roles in high-order harmonic generation from solid materials. In this work we provide a new all-optical technique to reconstruct the momentum-dependent transition dipole moment using the harmonic spectrum from MgO crystal driven by an ultrashort mid-infrared laser pulse. Under the influence of the ultrashort laser pulse, the emitted photon energy and the crystal momentum form a one-to-one match, in the same way between the intensity of the harmonic above the minimum bandgap and the square of the amplitude of the transition dipole moment, resulting in a realization of directly probing the transition dipole moment. Our all-optical method paves a way to image the two-dimensional transition dipole moment of crystals with the inversion symmetry.

4.
Blood Coagul Fibrinolysis ; 35(5): 271-278, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38874905

RESUMEN

Immune-mediated thrombotic thrombocytopenia purpura (iTTP) is a rare microvascular disease characterized by severe disseminated microvascular thrombose-bleeding syndrome. Caplacizumab has been approved for the treatment of iTTP in combination with Plasma Exchange (PE) and immunosuppressive therapy, but its role in iTTP therapy remains uncertain. Therefore, we conducted a meta-analysis to investigate the safety and efficacy of caplacizumab for the treatment of patients with iTTP. We searched electronic databases (PubMed, Embase, Cochrane Library, and Scopus) and reference lists of relevant articles to find articles published from 2015 to 2022. The time to normalization of the platelet count of the group caplacizumab is shorter than the group placebo (SMD = -0.72; 95% CI -0.88 to -0.56; P  < 0.05). Caplacizumab reduced the incidence of mortality (OR = 0.41; 95% CI 0.18-0.92; P  < 0.05), exacerbations (OR = 0.10; 95% CI 0.05-0.18; P  < 0.05), and recurrence (OR = 0.17; 95% CI 0.06-0.50; P  < 0.05). However, the bleeding events in the caplacizumab group were higher than those in the placebo group, especially severe bleeding events. There was no difference in ADAMTS13 activity and thromboembolic events between the two groups. Our analysis indicated that caplacizumab is effective and well tolerated for the treatment of iTTP. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42022362370.


Asunto(s)
Púrpura Trombocitopénica Trombótica , Anticuerpos de Dominio Único , Humanos , Púrpura Trombocitopénica Trombótica/tratamiento farmacológico , Púrpura Trombocitopénica Trombótica/terapia , Anticuerpos de Dominio Único/uso terapéutico , Intercambio Plasmático/métodos , Resultado del Tratamiento
5.
Curr Med Sci ; 41(1): 87-93, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33582911

RESUMEN

Insulin resistance is an essential characteristic of type 2 diabetes mellitus (T2DM), which can be induced by glucotoxicity and adipose chronic inflammation. Mesenchymal stem cells (MSCs) and their exosomes were reported to ameliorate T2DM and its complications by their immunoregulatory and healing abilities. Exosomes derived from MSCs contain abundant molecules to mediate crosstalk between cells and mimic biological function of MSCs. But the role of exosomes derived from human umbilical cord mesenchymal stem cells (hUC-MSCs) in insulin resistance of human adipocytes is unclear. In this study, exosomes were harvested from the conditioned medium of hUC-MSCs and added to insulin-resistant adipocytes. Insulin-stimulated glucose uptake was measured by glucose oxidase/peroxidase assay. The signal pathway involved in exosome-treated adipocytes was detected by RT-PCR and Western blotting. The biological characteristics and function were compared between hUC-MSCs and human adipose-derived mesenchymal stem cells (hAMSCs). The results showed that hAMSCs had better adipogenic ability than hUC-MSCs. After induction of mature adipocytes by adipogenesis of hAMSC, the model of insulin-resistant adipocytes was successfully established by TNF-α and high glucose intervention. After exosome treatment, the insulin-stimulated glucose uptake was significantly increased. In addition, the effect of exosomes could be stabilized for at least 48 h. Furthermore, the level of leptin was significantly decreased, and the mRNA expression of sirtuin-1 and insulin receptor substrate-1 was significantly upregulated after exosome treatment. In conclusion, exosomes significantly improve insulin sensitivity in insulin-resistant human adipocytes, and the mechanism involves the regulation of adipokines.


Asunto(s)
Adipocitos/metabolismo , Exosomas/metabolismo , Resistencia a la Insulina , Células Madre Mesenquimatosas/metabolismo , Adipocitos/citología , Diferenciación Celular , Células Cultivadas , Glucosa/metabolismo , Humanos , Insulina/metabolismo , Leptina/metabolismo , Células Madre Mesenquimatosas/citología , Sirtuina 1/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Cordón Umbilical/citología
6.
ACS Appl Mater Interfaces ; 12(42): 47840-47847, 2020 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-32981314

RESUMEN

Adenosine triphosphate (ATP) is mainly produced in mitochondria and plays an important role in lots of pathological processes such as colitis. Unfortunately, to date, few suitable fluorescence probes have been developed for monitoring the ATP level in colitis. Herein, a fluorescence nanoprobe named NIR@ZIF-90 is proposed and prepared by encapsulating a rhodamine-based near-infrared (NIR) dye into zeolitic imidazolate frameworks (ZIF-90). The nanoprobe is nonfluorescent because the emission of NIR is suppressed by the encapsulation, while in the presence of ATP, the framework of ZIF-90 is dissembled to release NIR and thus NIR fluorescence at 750 nm is observed. The nanoprobe shows high sensitivity to ATP with a 72-fold increase and excellent selectivity to ATP over other nucleotides. Moreover, with low cytotoxicity and good mitochondria-targeted ability, NIR@ZIF-90 is used to image ATP in colorectal cancer cells (HCT116). In addition, due to the NIR emission, the nanoprobe is further employed to successfully monitor the ATP level in a colitis mouse model. To the best of our knowledge, the nanoprobe is the first example to study colitis in vivo with the guidance of ATP, which will provide an efficient tool for understanding colitis.


Asunto(s)
Adenosina Trifosfato/análisis , Colitis/diagnóstico por imagen , Colorantes Fluorescentes/química , Estructuras Metalorgánicas/química , Imagen Óptica , Animales , Colitis/inducido químicamente , Sulfato de Dextran , Modelos Animales de Enfermedad , Células HCT116 , Humanos , Imidazoles/química , Rayos Infrarrojos , Ratones , Estructura Molecular , Tamaño de la Partícula , Propiedades de Superficie , Zeolitas/química
7.
Chem Commun (Camb) ; 55(95): 14307-14310, 2019 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-31713549

RESUMEN

A novel hepatocyte-targeting near-infrared fluorescent probe named Gal-NIR is developed. Gal-NIR shows ratiometric response to ONOO- with high sensitivity and selectivity. Moreover, the probe can accurately target the hepatocyte, and thus is used for assessing drug-induced hepatotoxicity and its remediation by using hepatoprotective medicines in living cells and mice.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Colorantes Fluorescentes/análisis , Hepatocitos/efectos de los fármacos , Imagen Óptica , Ácido Peroxinitroso/análisis , Acetaminofén/administración & dosificación , Acetaminofén/farmacología , Animales , Línea Celular Tumoral , Colorantes Fluorescentes/administración & dosificación , Colorantes Fluorescentes/química , Humanos , Rayos Infrarrojos , Ratones , Ratones Endogámicos BALB C , Estructura Molecular
8.
Medicine (Baltimore) ; 97(2): e9482, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29480835

RESUMEN

Using bone biopsy samples, we examined whether osteolytic cytokine profile is changed in situ in bone samples of metastatic multiple myeloma, and whether this creates an environment of lysis within the bone to which it has spread. This also produces the clinical features of increased circulating plasma calcium, and deleterious effects on the kidney.Using multiple myeloma biopsy and cell extracts from bone metastatic lesions, Bruton kinase, a tyrosine kinase, was demonstrated to be translocated to the membrane. Several transcription factors were upregulated included activin A, inflammatory transcription activator like such as nuclear factor kappa B, and specific bone lytic factor such as receptor activator of nuclear factor kappa-B ligand that is known to drive osteoclastogenesis as opposed to a osteogenic environment. The transcript for Bruton kinase was also elevated in its expression.Cytokines that support osteolytic activity such as a proliferation-inducing ligand, RANTES (regulated on activation, normal T cell expressed and secreted), interleukin-8, and activin A were upregulated. Tartrate resistant acid phosphatase (TRAP)-positive osteoclastic enzymatic activity was significantly elevated in the bone microenvironment in metastatic multiple myeloma. Several tyrosine kinase inhibitors, including inhibitors for Bruton kinase such as ibrutinib have been developed. The results of the present study provide evidence that multiple myeloma possess signal transduction mechanisms to support a bone lytic environment.The results provide a preliminary molecular basis to design specific inhibitors for management of bone metastasis of multiple myeloma.


Asunto(s)
Neoplasias Óseas/enzimología , Neoplasias Óseas/secundario , Membrana Celular/enzimología , Mieloma Múltiple/enzimología , Osteogénesis/fisiología , Proteínas Tirosina Quinasas/metabolismo , Activinas/metabolismo , Agammaglobulinemia Tirosina Quinasa , Anciano , Quimiocina CCL5/metabolismo , Humanos , Masculino , Persona de Mediana Edad , FN-kappa B/metabolismo , ARN Mensajero/metabolismo , Fosfatasa Ácida Tartratorresistente/metabolismo
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