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

RESUMO

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.


Assuntos
Oryza , Zeolitas , Cor , Resíduos Industriais , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Clin Biomech (Bristol, Avon) ; 41: 34-38, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27918892

RESUMO

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.


Assuntos
Músculos do Dorso/fisiopatologia , Debilidade Muscular/fisiopatologia , Espondilolistese/fisiopatologia , Adulto , Fenômenos Biomecânicos , Terapia por Exercício , Análise de Elementos Finitos , Humanos , Vértebras Lombares/fisiologia , Masculino , Postura/fisiologia , Espondilolistese/reabilitação , Articulação Zigapofisária/fisiologia
3.
PLoS One ; 8(9): e73952, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24023916

RESUMO

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.


Assuntos
Anticorpos Monoclonais/imunologia , Carcinoma Hepatocelular/imunologia , Quimiocina CCL21/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Neoplasias Hepáticas/imunologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/imunologia , Animais , Anticorpos Monoclonais/uso terapêutico , Antígeno CD11c/metabolismo , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Progressão da Doença , Feminino , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica/imunologia , Humanos , Interferon gama/biossíntese , Interleucina-12/biossíntese , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica
4.
PLoS One ; 8(9): e74430, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24040244

RESUMO

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.


Assuntos
Fatores de Transcrição Forkhead/genética , Linfócitos do Interstício Tumoral/metabolismo , Receptores CCR7/genética , Neoplasias Gástricas/genética , Linfócitos T Reguladores/metabolismo , Idoso , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Metástase Linfática , Linfócitos do Interstício Tumoral/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Linfócitos T Reguladores/patologia , Análise Serial de Tecidos
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