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1.
Zhonghua Nei Ke Za Zhi ; 61(5): 559-564, 2022 May 01.
Artículo en Chino | MEDLINE | ID: mdl-35488608

RESUMEN

Objective: To investigate the effect of interleukin-33 (IL-33) on lipopolysaccharide (LPS)-induced permeability of rat cardiac microvascular endothelial cells (RCMECs). Methods: RCMECs were cultured in vitro to be divided into control group, LPS group, IL-33 group and LPS+IL-33 group. The effect of IL-33 on the proliferation of RCMECs was detected by cell counting reagent (CCK8). Fluorescein isothiocyanate (FITC)-dextran assay was used to evaluate the permeability of RCMECs. The expression of vascular endothelial calmodulin, ras homologous gene family (Rho) member A (RhoA) and phosphorylated Rho-associated coiled-coil-containing protein kinase (p-ROCK2) proteins were tested by western blot. High-throughput sequencing and gene ontology (GO) were performed for gene expression in LPS and LPS+IL-33 groups. Results: No significant effect of IL-33 at 10-50 ng/ml on the proliferation of RCMECs was observed (P>0.05). Compared with the control group, the permeability of RCMECs (permeability coefficient ratio 1.404±0.029 vs. 1.000±0.200, P<0.05) was significantly increased in LPS group and the expression of vascular endothelial calmodulin (relative gray value 0.429 5±0.012 9 vs. 0.594 9±0.014 2, P<0.05) was down-regulated, while the permeability of monolayers (permeability coefficient ratio, 0.948±0.013, P<0.01) was decreased in LPS+IL-33 group and the expression of vascular endothelial calmodulin (relative grayscale value 0.549 1±0.012 0, P<0.005) was up-regulated compared with the LPS group. High-throughput sequencing data revealed that the differential genes downregulated in the LPS and LPS+IL-33 groups were associated with cytoskeleton and Rho signaling pathway. Compared with the control group, RhoA (relative gray value 0.211 4±0.009 9 vs. 0.135 0±0.007 6, P<0.000 1) and p-ROCK (relative gray value 0.656 3±0.013 2 vs. 0.503 6±0.036 2, P<0.000 1) protein expression was upregulated in the LPS group. When compared with LPS group, RhoA (relative gray value 0.157 7±0.010 7, P=0.000 2), p-ROCK (relative gray value 0.427 7±0.003 8, P<0.000 1) protein expression was decreased in LPS+IL-33 group. Conclusion: IL-33 may improve LPS-induced hyperpermeability of RCMECs by inhibiting RhoA and p-ROCK protein expression in Rho/Rho-associated coiled-coil-containing protein kinase signaling pathway.


Asunto(s)
Células Endoteliales , Lipopolisacáridos , Animales , Calmodulina/metabolismo , Calmodulina/farmacología , Permeabilidad Capilar/fisiología , Interleucina-33/metabolismo , Interleucina-33/farmacología , Lipopolisacáridos/metabolismo , Lipopolisacáridos/farmacología , Permeabilidad , Proteínas Quinasas/metabolismo , Proteínas Quinasas/farmacología , Ratas
2.
Phys Rev Lett ; 126(20): 201102, 2021 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-34110215

RESUMEN

The measurement of the energy spectrum of cosmic ray helium nuclei from 70 GeV to 80 TeV using 4.5 years of data recorded by the Dark Matter Particle Explorer (DAMPE) is reported in this work. A hardening of the spectrum is observed at an energy of about 1.3 TeV, similar to previous observations. In addition, a spectral softening at about 34 TeV is revealed for the first time with large statistics and well controlled systematic uncertainties, with an overall significance of 4.3σ. The DAMPE spectral measurements of both cosmic protons and helium nuclei suggest a particle charge dependent softening energy, although with current uncertainties a dependence on the number of nucleons cannot be ruled out.

3.
Sci Adv ; 5(9): eaax3793, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31799401

RESUMEN

The precise measurement of the spectrum of protons, the most abundant component of the cosmic radiation, is necessary to understand the source and acceleration of cosmic rays in the Milky Way. This work reports the measurement of the cosmic ray proton fluxes with kinetic energies from 40 GeV to 100 TeV, with 2 1/2 years of data recorded by the DArk Matter Particle Explorer (DAMPE). This is the first time that an experiment directly measures the cosmic ray protons up to ~100 TeV with high statistics. The measured spectrum confirms the spectral hardening at ~300 GeV found by previous experiments and reveals a softening at ~13.6 TeV, with the spectral index changing from ~2.60 to ~2.85. Our result suggests the existence of a new spectral feature of cosmic rays at energies lower than the so-called knee and sheds new light on the origin of Galactic cosmic rays.

5.
RSC Adv ; 8(6): 2900-2905, 2018 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-35541187

RESUMEN

Methylammonium (MA) and formamidinium (FA) are two typical A site cations in lead halide perovskites. Instability of synthesised crystals will degrade the properties of the photoelectrical device constructed by such perovskites. MAPbI3 and FAPbI3 in cubic crystal structure have been demonstrated to be the most stable at room temperature. Herein we synthesised MA(EA)PbI3 and FA(MA)PbI3 single crystals using an inverse-temperature crystallization strategy by partially substituting the methylammonium (MA) with ethylammonium (EA) and the formamidinium (FA) with methylammonium (MA) respectively. The XRD results show that both crystal structures are cubic, which means organic incorporation can stabilize the crystal structure of lead halide perovskites. The lattice distortion decrease and strain relaxation in single crystals were considered to be the reason leading to higher stability. The single crystals of MA(EA)PbI3 and FA(MA)PbI3 with low trap state density exhibit excellent light-absorbing properties, indicating their potential applications in photoelectric devices.

6.
Ultraschall Med ; 37(6): 609-618, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25919414

RESUMEN

Purpose: To investigate the factors that influence the enhancement patterns of intrahepatic cholangiocarcinomas (ICC) on contrast-enhanced ultrasound (CEUS) and analyze the correlations between the enhancement patterns on CEUS and pathological findings. Materials and Methods: Ninety-six patients with 96 pathologically confirmed ICCs underwent CEUS. CEUS images were retrospectively evaluated for tumor enhancement patterns in the arterial, portal and late phases. The arterial enhancement patterns were correlated with clinicopathological factors. The possible influencing factors were correlated with pathologic findings. Results: Thirty-six patients with ICC demonstrated rim-like enhancement, and 60 exhibited non-rim-like enhancement in the arterial phase on CEUS. The incidence of non-rim-like-enhancing ICCs was higher in patients with cirrhosis and chronic viral hepatitis than patients with no chronic liver disease (p = 0.001). The sizes of the ICCs with homogeneous hyper-enhancement were significantly smaller than those with inhomogeneous hyper-enhancement (p = 0.007). Arterial non-rim-like-enhancing ICCs showed higher microvessel density (MVD) and arterial density (AD) and less fibrous stroma and necrosis than rim-like-enhancing ICCs. Arterial inhomogeneous-enhancing ICCs had lower MVD and AD and much more fibrous stroma and necrosis than homogeneous-enhancing ICCs. Conclusion: The enhancement pattern of ICCs in the arterial phase on CEUS was affected by a liver cirrhosis and chronic viral hepatitis and tumor size. The amount of MVD, AD, fibrous stroma and necrosis in ICC tumors may be responsible for the difference in the enhancement patterns.


Asunto(s)
Neoplasias de los Conductos Biliares/diagnóstico por imagen , Conductos Biliares Intrahepáticos/diagnóstico por imagen , Colangiocarcinoma/diagnóstico por imagen , Medios de Contraste , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Adulto , Anciano , Neoplasias de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos/patología , Colangiocarcinoma/patología , Enfermedad Crónica , Medios de Contraste/farmacocinética , Femenino , Hepatitis B Crónica/diagnóstico por imagen , Hepatitis B Crónica/patología , Humanos , Hígado/diagnóstico por imagen , Hígado/patología , Cirrosis Hepática/diagnóstico por imagen , Cirrosis Hepática/patología , Masculino , Persona de Mediana Edad , Necrosis , Estadificación de Neoplasias , Estudios Retrospectivos , Estadística como Asunto
7.
Eur Rev Med Pharmacol Sci ; 18(14): 2006-12, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25027339

RESUMEN

AIM: This study aims to evaluate the clinical efficacy and safety of intravenous Cefoselis injection for the treatment of acute moderate and severe bacterial infections. PATIENTS AND METHODS: A multicenter, double-blind, randomized clinical trial was carried out using Cefepime as control. Patients received 1.0 g of either Cefoselis or Cefepime for moderate infections or 2.0 g for severe infections at an interval of 12 hours for 7 to 14 days. A total of 276 patients (138 with Cefoselis, 138 with Cefepime) with respiratory or urinary tract infections were enrolled in the study. Up to 137 and 124 patients receiving Cefoselis and 132 and 125 patients receiving Cefepime were eligible for the ITT (intent to treat) and PP (per protocol) analyses, respectively. RESULTS: At the end of the treatment, the cure rates and effective rates were 59.68% (74/124) and 93.55% (116/124) with Cefoselis, and 56.00% (74/124) and 90.40% (116/124) with Cefepime. The bacterial eradication rates of the two groups were 90.32% and 93.85%, respectively. No statistical differences were observed on the above-mentioned parameters between the two groups (all p > 0.05). Adverse events, mainly mild aminotransferase elevation and mild leukopenia, were observed in 11.59% (16/138) and 13.77% (19/138) of patients with Cefoselis and Cefepime, respectively (p > 0.05). CONCLUSIONS: Cefoselis is an effective and safe choice against acute moderate and severe respiratory infections and UTI (urinary tract infection).


Asunto(s)
Antibacterianos/administración & dosificación , Infecciones Bacterianas/tratamiento farmacológico , Ceftizoxima/análogos & derivados , Cefalosporinas/administración & dosificación , Enfermedad Aguda , Cefepima , Ceftizoxima/administración & dosificación , Método Doble Ciego , Femenino , Humanos , Masculino , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones Urinarias/tratamiento farmacológico
8.
Genet Mol Res ; 12(3): 2841-51, 2013 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-23359055

RESUMEN

We developed and characterized expressed sequence tags (ESTs)-simple sequence repeats (SSRs) and targeted region amplified polymorphism (TRAP) markers to examine genetic relationships in the persimmon genus Diospyros gene pool. In total, we characterized 14 EST-SSR primer pairs and 36 TRAP primer combinations, which were amplified across 20 germplasms of 4 species in the genus Diospyros. We used various genetic parameters, including effective multiplex ratio (EMR), diversity index (DI), and marker index (MI), to test the utility of these markers. TRAP markers gave higher EMR (24.85) but lower DI (0.33), compared to EST-SSRs (EMR = 3.65, DI = 0.34). TRAP gave a very high MI (8.08), which was about 8 times than the MI of EST-SSR (1.25). These markers were utilized for phylogenetic inference of 20 genotypes of Diospyros kaki Thunb. and allied species, with a result that all kaki genotypes clustered closely and 3 allied species formed an independent group. These markers could be further exploited for large-scale genetic relationship inference.


Asunto(s)
Diospyros/genética , Etiquetas de Secuencia Expresada , Repeticiones de Microsatélite/genética , Cartilla de ADN/genética , Genoma de Planta , Genotipo , Japón , Filogenia
9.
J Nanosci Nanotechnol ; 12(4): 3040-7, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22849063

RESUMEN

Gamma-Fe2.6Ni1.4 nanoparticles were prepared by the arc-discharge method as the precursor and its nitride counterpart of gamma'-Fe2.6Ni14N nanoparticles was synthesized directly through a thermal ammonolysis reaction at the temperature of 673 K for two hours. The resultant product was identified as a homogeneous ternary nitride with nearly spherical shape and average size of about 60.0 nm. The electromagnetic characteristics of gamma'-Fe2.6Ni1.4N derivant and gamma-Fe2.6Ni1.4 precursor have been studied in the frequency range of 2-18 GHz. Compared with the precursor, gamma'-Fe2.6Ni1.4N nanoparticles exhibits an enhanced electromagnetic absorption property resulted from the increased dielectric loss by nitriding process. The optimal reflection loss (RL) of gamma'-Fe2.6Ni1.4N nanoparticles/paraffin composite can reach -39.9 dB at 5.2 GHz in a thickness of 2.29 mm, and the frequency band corresponding RL < -10 dB is over 2.6-18 GHz in the thickness range of 0.78-4.20 mm.

10.
Am J Transplant ; 10(5): 1178-88, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20420630

RESUMEN

In this study, we aimed to investigate the significance of hepatic stellate cells (HSCs) activation in small-for-size fatty liver graft injury and to explore the underlying molecular mechanism in a rat liver transplantation model. A rat orthotopic liver transplantation model using fatty grafts (40% of fatty changes) and cirrhotic recipients was applied. Intragraft gene expression profiles, ultrastructure features and HSCs activation were compared among the rats received different types of grafts (whole vs. small-for-size, normal vs. fatty). The distinct molecular signature of small-for-size fatty graft injury was identified by cDNA microarray screening and confirmed by RT-PCR detection. In vitro functional studies were further conducted to investigate the direct effect of specific molecular signature on HSCs activation. HSCs activation was predominantly present in small-for-size fatty grafts during the first 2 weeks after transplantation, and was strongly correlated with progressive hepatic sinusoidal damage and significant upregulation of intragraft Wnt4 signaling pathway. In vitro suppression of Wnt4 expression could inhibit HSC activation directly. In conclusion, upregulation of Wnt4 signaling led to direct HSC activation and subsequently induced small-for-size fatty liver grafts injury. Discovery of this distinct mechanism may lay the foundation for prophylactic treatment for marginal graft injury in living donor liver transplantation.


Asunto(s)
Transducción de Señal/genética , Animales , Hígado Graso/patología , Perfilación de la Expresión Génica , Células Estrelladas Hepáticas , Trasplante de Hígado/fisiología , Donadores Vivos , Masculino , Análisis de Secuencia por Matrices de Oligonucleótidos , Ratas , Ratas Sprague-Dawley , Procedimientos de Cirugía Plástica , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Regulación hacia Arriba , Proteínas Wnt , Proteína Wnt4
12.
Acta Crystallogr A ; 58(Pt 4): 361-9, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12089459

RESUMEN

As a basis for direct-methods phasing at very low resolution for macromolecular crystal structures, normalized structure-factor algebra is presented for few-atoms structure models with N = 1, 2, 3, em leader equal atoms or polyatomic globs per unit cell. Main results include: [see text]. Triplet discriminant Delta(hk) and triplet weight W(hk) parameters, a approximately 4.0 and b approximately 3.0, respectively, were determined empirically in numerical error analyses. Tests with phases calculated for few-atoms 'super-glob' models of the protein apo-D-glyceraldehyde-3-phosphate dehydrogenase (approximately 10000 non-H atoms) showed that low-resolution phases from the new few-atoms tangent formula were much better than conventional tangent formula phases for N = 2 and 3; phases from the two formulae were essentially the same for N > or = 4.


Asunto(s)
Cristalización , Matemática , Estructura Molecular , Modelos Moleculares
14.
Acta Crystallogr D Biol Crystallogr ; 56(Pt 9): 1148-55, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10957633

RESUMEN

Probabilistic direct-methods phasing theory, originally based on a uniform atomic distribution hypothesis, is shown to be adaptable to a non-uniform bulk-solvent-compensated globbic approximation for protein crystals at low resolution. The effective number n(g) of non-H protein atoms per polyatomic glob increases with decreasing resolution; low-resolution phases depend on the positions of only N(g) = N(a)/n(g) globs rather than N(a) atoms. Test calculations were performed with measured structure-factor data and the refined structural parameters from a protein crystal with approximately 10 000 non-H protein atoms per molecule and approximately 60% solvent volume. Low-resolution data sets with d(min) ranging from 15 to 5 A gave n(g) = ad(min) + b, with a = 1.0 A(-1) and b = -1.9 for the test case. Results of tangent-formula phase-estimation trials emphasize that completeness of the low-resolution data is critically important for probabilistic phasing.


Asunto(s)
Cristalografía por Rayos X/métodos , Pliegue de Proteína , Proteínas/química , Cristalización , Cómputos Matemáticos , Conformación Proteica , Solventes
15.
Acta Crystallogr D Biol Crystallogr ; 56(Pt 4): 451-7, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10739918

RESUMEN

It is shown that for crystals of large proteins at low diffraction resolution, with N approximately 10 000 independent non-H protein atoms and d(min) approximately 8 A, a simple bulk-solvent correction yields the Sayre equation in its classical form, F(h) = q summation operator(k)F(k)F(h - k). In the low-resolution protein case, the proportionality factor becomes q = 1/[( - rho(S))V], where V is the unit-cell volume, rho(S) is the assumed constant electron density in the solvent regions of the crystal and is the average electron density in the protein regions. The classical form of the tangent formula follows from the bulk-solvent-corrected Sayre equation and its validity at low resolution is verified in empirical calculations.


Asunto(s)
Gliceraldehído-3-Fosfato Deshidrogenasas/química , Hidrolasas/química , Proteínas/química , Adenosilhomocisteinasa , Cristalografía por Rayos X/métodos , Análisis de Fourier , Modelos Teóricos , Probabilidad , Solventes
16.
Acta Crystallogr D Biol Crystallogr ; 55(Pt 1): 230-7, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10089414

RESUMEN

Using Harker's [Harker (1953). Acta Cryst. 6, 731-736] idea of spherically averaged polyatomic groups or 'globs' as the units of structure suitable for analyzing low-resolution diffraction data from protein crystals, 'globbic' scattering factors have been calculated for main-chain peptide units and amino-acid side-chain groups to 3 A resolution via Debye's [Debye (1915). Ann. Phys. (Leipzig), 46, 809-823] scattering formula. It is shown that the scattering factors are insensitive to intra-globbic conformational variation and can be approximated fairly well by a single-Gaussian formula, i.e. fg(s) = Zg exp(-1.7Zgs2), where s = (sin theta)/lambda and Zg is the total electron count for the atoms of the glob. Phase errors due to the globbic approximation and their effect on electron-density maps at 3.5 A resolution have been assessed via calculations for the crambin structure; this analysis indicates that the globbic scattering factors will be useful in efforts to develop procedures for direct-methods phasing of diffraction data to approximately 3.5 A resolution from protein crystals.


Asunto(s)
Cristalografía por Rayos X , Conformación Proteica , Interpretación Estadística de Datos , Electroquímica , Modelos Moleculares , Dispersión de Radiación
17.
Acta Crystallogr A ; 53 ( Pt 1): 74-83, 1997 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-9037748

RESUMEN

Results from probabilistic theory for the single-wavelength anomalous-scattering (SAS) Friedel pair, two-phase structure invariants, psi H = phi H + phi-H, are used to show that the SAS three-phase structure invariants, psi HK = phi H + phi K + phi-H-K, tend to positive values that are easily estimated. Appropriate averages of the estimates provide SAS perturbation corrections in the form of positive origin shifts for the probability distribution of psi HK values and for the tangent formula. The theoretical probabilistic results are verified by empirical statistical analyses of model-calculated phases and experimentally measured structure-factor magnitudes for a small-molecule and a protein crystal structure.


Asunto(s)
Química Física/métodos , Proteínas/química , Dispersión de Radiación , Cómputos Matemáticos , Probabilidad , Rayos X
18.
Acta Crystallogr D Biol Crystallogr ; 52(Pt 2): 257-66, 1996 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-15299698

RESUMEN

If the unit-cell distribution of atomic mean-square displacement parameters B = 8pi(2) is assumed to be normal, with mean micro = and variance sigma(2) = <(B-)(2)>, the statistical expectation value of the Debye-Waller factor W(2) = exp(-2Bs(2)), where s = (sin theta)/lambda, is = exp[-2( micro - sigma(2)s(2))s(2)]. This result has been incorporated into procedures for scaling and normalizing measured Bragg intensities to their Wilson expectation values. The procedures can determine both isotropic micro (B) and sigma(B) and anisotropic micro (U(ij)) and sigma(U(ij) distribution parameters. Tests with experimental data and refined structural models for several protein crystals show that the procedures yield reliable normalized structure-factor amplitudes for direct-methods applications, with values of R = summation operator (h)||E(o)| - |E(c)||/ summation operator (h)|E(o)| averaging approximately 5%.

19.
Acta Crystallogr A ; 51 ( Pt 6): 945-7, 1995 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-7488350

RESUMEN

At 3 to 4 A resolution, the electron density of a protein may be modeled by a continuous chain of 'globs' representing the amide region of the peptide backbone and the side-chain residues. Group scattering factors are derived from a trans planar C alpha C = ONC alpha backbone segment and most favored side-chain conformer for 18 different amino acids. Trial calculations indicate that the phase error and crystallographic residual comparing the atomic and 'globic' models rapidly decrease from high to low resolution. At 3 A resolution, the phase error is approximately 80 degrees. These results indicate that the electron density of a protein composed of N amino acid residues may be adequately modeled by 2N globs at low resolution.


Asunto(s)
Proteínas/química , Dispersión de Radiación , Aminoácidos/química , Cristalización , Matemática , Proteínas de Plantas/química , Conformación Proteica , Rayos X
20.
Acta Crystallogr A ; 50 ( Pt 3): 307-11, 1994 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-8024726

RESUMEN

For diffraction data at two wavelengths from a crystal with anomalous scatterers, there are six types of two-phase structure invariants for Friedel pairs. Two of the six are single-wavelength invariants; the other four are mixed-wavelength invariants. It is shown that the latter can be estimated by a straightforward extension of results from the probabilistic direct-methods theory for the single-wavelength anomalous scattering case described in paper I [Hauptman (1982). Acta Cryst. A38, 632-641]. Statistical tests of the mixed-wavelength estimates are reported for small-molecule and macro-molecular examples.


Asunto(s)
Difracción de Rayos X , Matemática , Estructura Molecular
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