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1.
Environ Sci Pollut Res Int ; 27(10): 10910-10924, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31953764

RESUMEN

Discarded industrial zeolite waste and agricultural rice husks have caused a waste of resources. To achieve resource reuse, we proposed an economical method for the preparation of ultramarine pigments via the reclamation of industrial zeolite waste (ZW) and agricultural rice husks (RHs) or previously bio-charred rice husks (BRHs). The optimal blue and green pigments were synthesized by solid state reaction of mixtures of BRH/ZW/Na2CO3/S with mass ratios of 1:2:1:1.5 and 2:2:7:3, respectively, and using a two-step calcination process with a first stage at 500 and a second stage at 800 °C. Furthermore, the blue and green pigments were also obtained using directly RH (instead of BRH) as raw material, but this time with RH/ZW/Na2CO3/S mass ratios of 1:2:2:3 and 1:2:7:3.5 and with first-stage and second-stage calcination temperatures of 400 and 800 °C. This was done to reduce additional chemical reactions (e.g., BRH derived from the pyrolysis of RH). The XRD, FT-IR, Raman, and SEM results suggest that the synthetic blue and green pigments have the sodalite structure containing S3- and S2- radicals. The synthetic green pigment using RH as raw material had the best acid resistance. Additionally, the synthesis of blue and green ultramarine pigments via the reclamation of the industrial zeolite wastes and agricultural rice husks can reduce the costs of the production process.


Asunto(s)
Oryza , Zeolitas , Color , Residuos Industriales , Espectroscopía Infrarroja por Transformada de Fourier
2.
Clin Biomech (Bristol, Avon) ; 41: 34-38, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27918892

RESUMEN

BACKGROUND: Whether muscle weakness is a cause, or result, of degenerative spondylolisthesis is not currently well understood. Little biomechanical evidence is available to offer an explanation for the mechanism behind exercise therapy. Therefore, the aim of this study is to investigate the effects of back muscle weakness on degenerative spondylolisthesis and to tease out the biomechanical mechanism of exercise therapy. METHODS: A nonlinear 3-D finite element model of L3-L5 was constructed. Forces representing global back muscles and global abdominal muscles, follower loads and an upper body weight were applied. The force of the global back muscles was reduced to 75%, 50% and 25% to simulate different degrees of back muscle weakness. An additional boundary condition which represented the loads from other muscles after exercise therapy was set up to keep the spine in a neutral standing position. Shear forces, intradiscal pressure, facet joint forces and von Mises equivalent stresses in the annuli were calculated. FINDINGS: The intervertebral rotations of L3-L4 and L4-L5 were within the range of in vitro experimental data. The calculated intradiscal pressure of L4-L5 for standing was 0.57MPa, which is similar to previous in vivo data. With the back muscles were reduced to 75%, 50% and 25% force, the shear force moved increasingly in a ventral direction. Due to the additional stabilizing force and moment provided by boundary conditions, the shear force varied less than 15%. INTERPRETATION: Reducing the force of global back muscles might lead to, or aggravate, degenerative spondylolisthesis with forward slipping from biomechanical point of view. Exercise therapy may improve the spinal biomechanical environment. However, the intrinsic correlation between back muscle weakness and degenerative spondylolisthesis needs more clinical in vivo study and biomechanical analysis.


Asunto(s)
Músculos de la Espalda/fisiopatología , Debilidad Muscular/fisiopatología , Espondilolistesis/fisiopatología , Adulto , Fenómenos Biomecánicos , Terapia por Ejercicio , Análisis de Elementos Finitos , Humanos , Vértebras Lumbares/fisiología , Masculino , Postura/fisiología , Espondilolistesis/rehabilitación , Articulación Cigapofisaria/fisiología
3.
PLoS One ; 8(9): e73952, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24023916

RESUMEN

CCL21 is known to attract dendritic cells (DCs) and T cells that may reverse tumor-mediated immune suppression. The massive infiltration of tumors by regulatory T cells (Tregs) prevents the development of a successful helper immune response. In this study, we investigated whether elimination of CD4(+) CD25(+) Tregs in the tumor microenvironment using anti-CD25 monoclonal antibodies (mAbs) was capable of enhancing CCL21-mediated antitumor immunity in a mouse hepatocellular carcinoma (HCC) model. We found that CCL21 in combination with anti-CD25 mAbs (PC61) resulted in improved antitumor efficacy and prolonged survival, not only inhibited tumor angiogenesis and cell proliferation, but also led to significant increases in the frequency of CD4(+), CD8(+) T cells and CD11c(+) DCs within the tumor, coincident with marked induction of tumor-specific CD8(+) cytotoxic T lymphocytes (CTLs) at the local tumor site. The intratumoral immune responses were accompanied by the enhanced elaboration of IL-12 and IFN-γ, but reduced release of the immunosuppressive mediators IL-10 and TGF-ß1. The results indicated that depletion of Tregs in the tumor microenvironment could enhance CCL21-mediated antitumor immunity, and CCL21 combined with anti-CD25 mAbs may be a more effective immunotherapy to promote tumor rejection.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Carcinoma Hepatocelular/inmunología , Quimiocina CCL21/metabolismo , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Neoplasias Hepáticas/inmunología , Linfocitos T Reguladores/citología , Linfocitos T Reguladores/inmunología , Animales , Anticuerpos Monoclonales/uso terapéutico , Antígeno CD11c/metabolismo , Carcinoma Hepatocelular/irrigación sanguínea , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Progresión de la Enfermedad , Femenino , Factores de Transcripción Forkhead/metabolismo , Regulación Neoplásica de la Expresión Génica/inmunología , Humanos , Interferón gamma/biosíntesis , Interleucina-12/biosíntesis , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Ratones , Ratones Endogámicos C57BL , Neovascularización Patológica
4.
PLoS One ; 8(9): e74430, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24040244

RESUMEN

The aim of this study was to investigate the prognostic value of chemokine receptor CCR7 expression and intratumoral FOXP3(+) regulatory T cells (Tregs) in gastric cancer. CCR7(+) tumor cells and FOXP3(+) Tregs were assessed by immunohistochemistry in tissue microarrays containing gastric cancer from 133 patients. Prognostic effects of low or high CCR7 and FOXP3 expression were evaluated by Cox regression and Kaplan-Meier analysis, as well as the correlation between CCR7 positive score and intratumoral FOXP3(+) cell number in a longitudinal assessment. The analysis showed that the high expression levels of CCR7 and FOXP3 were detected in 69.9% and 65.4% of cases, respectively. High CCR7 expression in gastric cancer cells was significantly associated with poor overall survival (OS) (P = 0.010) and lymph node metastasis (P = 0.009), and was an independent factor for worse OS (P = 0.023) by multivariate analysis. High numbers of intratumoral FOXP3(+) Tregs significantly correlated with shorter OS (P = 0.021) and lymph node metastasis (P = 0.024), and was also an independent factor for adverse OS (P = 0.035). Furthermore, there was a significantly positive correlation between CCR7 positive score and intratumoral FOXP3(+) cell number (r = 0.949, P<0.001). These results revealed that CCR7 expression in gastric cancer cells and intratumoral FOXP3(+) Tregs could be considered as a co-indicator of clinical prognosis of gastric cancer.


Asunto(s)
Factores de Transcripción Forkhead/genética , Linfocitos Infiltrantes de Tumor/metabolismo , Receptores CCR7/genética , Neoplasias Gástricas/genética , Linfocitos T Reguladores/metabolismo , Anciano , Femenino , Expresión Génica , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Metástasis Linfática , Linfocitos Infiltrantes de Tumor/patología , Masculino , Persona de Mediana Edad , Pronóstico , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Linfocitos T Reguladores/patología , Análisis de Matrices Tisulares
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