Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
Polymers (Basel) ; 16(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-39000642

RESUMO

Wood-plastic composites are becoming increasingly recognized for their sustainability and their potential for use in various production processes. Nevertheless, enhancing their mechanical strength continues to be a difficult challenge. The objective of this research was to improve the mechanical strength of wood-plastic composite components manufactured through selective laser sintering (SLS). This was achieved by integrating a sustainable composite material, Prosopis chilensis (PCP), with polyethersulfone (PES) to form a composite referred to as PCPC. This study showcased the effect of various PCP particle sizes on mechanical strengths, dimensional accuracies (DAs), and surface roughness of PCPC parts manufactured using AFS-360 SLS. Single-layer sintering was employed to assess PCPC powder's formability with varying PCP particle sizes, and various tests were conducted to understand the materials' thermal properties and analyze particle dispersion and microstructure. The results demonstrated that PCP particle sizes ≤ 0.125 mm significantly enhanced the mechanical strength, forming quality, and DA compared to other particle sizes and pure PES. Key findings for PCPC parts with PCP ≤ 0.125 mm included a bending strength of 10.78 MPa, a tensile strength of 4.94 MPa, an impact strength of 0.91 kJ/m2, and a density of 1.003 g/cm3. Post-processing further improved these parameters, confirming that optimizing PCP particle size is crucial for enhancing the mechanical properties and overall quality of PCPC parts produced via SLS.

2.
Inorg Chem ; 62(6): 2951-2957, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36719137

RESUMO

The exploitation of efficient and economical electrocatalysts for hydrogen evolution reaction (HER) is of exceeding interest in renewable clean-energy technologies. Herein, the facile solvothermal reaction of S and chromic acetate in ethylenediamine (en) achieved a novel organic hybrid chromium sulfide [Cr4(µ3-S)4(en)4(SH)4]·0.25H2O (1), which offers a new type of antiferromagnetic cubane-like chromium sulfide cluster with σ-donor en ligands. 1 was utilized in combination with Ni nanoparticles and porous Ni foam (NF) to fabricate a Ni/1/NF electrode as an efficient cathodic catalyst, indicating excellent electrocatalytic property toward HER.

3.
Clin Transl Oncol ; 25(1): 105-113, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36068448

RESUMO

Myelodysplastic syndrome (MDS) consists of a group of hematologic tumors that are derived from the clonal proliferation of hematopoietic stem cells, featuring abnormal hematopoietic cell development and ineffective hematopoiesis. Animal models are an important scientific research platform that has been widely applied in the research of human diseases, especially tumors. Animal models with MDS can simulate characteristic human genetic variations and tumor phenotypes. They also provide a reliable platform for the exploration of the pathogenesis and diagnostic markers of MDS as well as for a drug efficacy evaluation. This paper reviews the research status of three animal models and a new spontaneous mouse model with MDS.


Assuntos
Neoplasias Hematológicas , Síndromes Mielodisplásicas , Animais , Camundongos , Humanos , Síndromes Mielodisplásicas/genética , Células-Tronco Hematopoéticas/patologia , Modelos Animais de Doenças , Hematopoese
4.
Ann Hepatol ; 25: 100538, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34555511

RESUMO

N6-methyladenosine (m6A) is the most thoroughly studied type of internal RNA modification, as this epigenetic modification is the most abundant in eukaryotic RNAs to date. This modification occurs in various types of RNAs and plays significant roles in dominant RNA-related processes, such as translation, splicing, export and degradation. These processes are catalyzed by three types of prominent enzymes: writers, erasers and readers. Increasing evidence has shown that m6A modification is vital for the regulation of gene expression, carcinogenesis, tumor progression and other abnormal changes, and recent studies have shown that m6A is important in the development of hepatocellular carcinoma (HCC). Herein, we summarize the nature and regulatory mechanisms of m6A modification, including its role in the pathogenesis of HCC and related chronic liver diseases. We also highlight the clinical significance and future strategies involving RNA m6A modifications in HCC.


Assuntos
Adenosina/análogos & derivados , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/patologia , Adenosina/fisiologia , Humanos
5.
Braz. j. microbiol ; Braz. j. microbiol;48(2): 218-224, April.-June 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-839380

RESUMO

Abstract The severity of Helicobacter pylori-related disease is correlated with the presence and integrity of a cag pathogenicity island (cagPAI). cagPAI genotype may have a modifying effect on the pathogenic potential of the infecting strain. After analyzing the sequences of cagPAI genes, some strains with the East Asian-type cagPAI genes were selected for further analysis to examine the association between the diversity of the cagPAI genes and the virulence of H. pylori. The results showed that gastric mucosal inflammatory cell infiltration was significantly higher in patients with East Asian-type cagPAI genes H. pylori strain compared with mosaicism cagPAI genes H. pylori strain (p < 0.05). H. pylori strains with the East Asian-type cagPAI genes were closely associated with IL-8 secretion in vitro and in vivo compared with H. pylori strains with the mosaicism cagPAI genes (p < 0.01). H. pylori strains with East Asian-type cagPAI genes are able to strongly translocate CagA to host cells. These results suggest that H. pylori strains with East Asian-type cagPAI genes are more virulent than the strains of cagPAI gene/genes that are Western type.


Assuntos
Humanos , Helicobacter pylori/classificação , Helicobacter pylori/genética , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Ilhas Genômicas , Genótipo , Filogenia , Virulência , Análise por Conglomerados , Helicobacter pylori/isolamento & purificação , Fatores de Virulência/genética , Mucosa Gástrica/patologia , Histocitoquímica , Microscopia
6.
Braz. J. Microbiol. ; 48(2): 218-224, abr.-jun. 2017. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-17487

RESUMO

A gravidade da Helicobacter pylori relacionados com a doença está relacionada com a presença e a integridade de uma cag ilha de patogenicidade ( cag PAI). O genótipo de cag PAI pode ter um efeito modificador sobre o potencial patogênico da cepa infectante. Depois de analisar as seqüências de genes de cag PAI, algumas cepas com os genes PAI de cag do tipo do Leste Oriental foram selecionadas para análise posterior para examinar a associação entre a diversidade dos genes PAI cag e a virulência de H. pylori . Os resultados mostraram que a infiltração de células inflamatórias da mucosa gástrica foi significativamente maior em pacientes com genes PAI cag do leste asiáticoH. pylori estirpe em comparação com mosaicismo cag genes PAI H. pylori estirpe ( p <0,05). As cepas de H. pylori com os genes PAI do cag do tipo do Leste Asiático foram intimamente associadas à secreção de IL-8 in vitro e in vivo em comparação com cepas de H. pylori com os genes PAI do mosaicism cag ( p <0,01). As cepas de H. pylori com genes PAI cag do leste asiático são capazes de translocar fortemente CagA para células hospedeiras. Estes resultados sugerem que as cepas de H. pylori com cag do tipo East AsianOs genes PAI são mais virulentos do que as cepas do gene / genes PAI de CAG que são de tipo ocidental.(AU)


Assuntos
Helicobacter pylori/patogenicidade , Virulência , Ilhas Genômicas , Interleucina-8 , Ásia Oriental , Ocidente , Japão , China , Inglaterra
7.
Braz J Microbiol ; 48(2): 218-224, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28130020

RESUMO

The severity of Helicobacter pylori-related disease is correlated with the presence and integrity of a cag pathogenicity island (cagPAI). cagPAI genotype may have a modifying effect on the pathogenic potential of the infecting strain. After analyzing the sequences of cagPAI genes, some strains with the East Asian-type cagPAI genes were selected for further analysis to examine the association between the diversity of the cagPAI genes and the virulence of H. pylori. The results showed that gastric mucosal inflammatory cell infiltration was significantly higher in patients with East Asian-type cagPAI genes H. pylori strain compared with mosaicism cagPAI genes H. pylori strain (p<0.05). H. pylori strains with the East Asian-type cagPAI genes were closely associated with IL-8 secretion in vitro and in vivo compared with H. pylori strains with the mosaicism cagPAI genes (p<0.01). H. pylori strains with East Asian-type cagPAI genes are able to strongly translocate CagA to host cells. These results suggest that H. pylori strains with East Asian-type cagPAI genes are more virulent than the strains of cagPAI gene/genes that are Western type.


Assuntos
Ilhas Genômicas , Genótipo , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Helicobacter pylori/classificação , Helicobacter pylori/genética , Fatores de Virulência/genética , Análise por Conglomerados , Mucosa Gástrica/patologia , Helicobacter pylori/isolamento & purificação , Histocitoquímica , Humanos , Microscopia , Filogenia , Virulência
8.
Hum Immunol ; 77(10): 869-875, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27343992

RESUMO

The aim of this study was to analyze the genetic profiles of 14 killer cell immunoglobulin-like receptor (KIR) genes and 2 pseudogenes of 124 individuals from Tujia ethnic minority residing in Enshi Tujia and Miao autonomous prefecture of Hubei province of China and investigate the genetic relationships between the Tujia ethnic minority and other reported groups for the first time. Sequence specific primer amplification (PCR-SSP) methods were used to genotype the 14 KIR genes and 2 pseudogenes. The observed carrier frequencies (OF) and the gene frequencies (GF) of the KIR genes were measured. Neighbor-joining (N-J) tree and the principal component analysis (PCA) plot were constructed. All individuals were typed positive for the three framework loci KIR3DL3, 2DL4 and 3DL2, as well as for pseudogene KIR3DP1. The gene frequencies of the other KIR genes ranged from 9% in KIR2DS2 to 98% in KIR2DP1 and KIR3DL1. The present study of the KIR genes may be a powerful tool for enriching the Chinese ethnical gene information resources of the KIR gene pool, as well as for the anthropological research.


Assuntos
Etnicidade , Células Matadoras Naturais/imunologia , Pseudogenes/genética , Receptores KIR/genética , Povo Asiático , China , Frequência do Gene , Genética Populacional , Genótipo , Humanos , Desequilíbrio de Ligação , Polimorfismo Genético
9.
Rev. bras. ciênc. avic ; 15(3): 191-197, July-Sept. 2013. tab
Artigo em Inglês | VETINDEX | ID: biblio-1490012

RESUMO

The aim of the present study was to determine whether dietary Bacillus subtilis natto could affect growth performance of Muscovy ducks. A total of 120 hundred Muscovy ducks at the age of 1 day were randomly assigned to four groups (30 Muscovy ducks/group), and fed with diets supplemented with 0% (control group), 0.1%, 0.2%, and 0.4% Bacillus subtilis natto, respectively during the 6-week feeding period. Weight gain, feed intake and feed conversion efficiency of Muscovy ducks were significantly improved by the dietary addition of Bacillus subtilis natto, and the results were more significant in 0.4% dietary Bacillus subtilis natto treatment group; Also, Bacillus subtilis natto reduced Escherichia coli and Salmonella colonies, and increased lactobacilli population in the ileum and the cecum. Biochemical parameters, including total protein, GOT (glutamic oxaloacetic transaminase), GPT (glutamic pyruvic transaminase), AKP (alkaline phosphatase), triiodothyronine (T3) and tetraiodothyronine (T4) contents (pBacillus subtilis natto was added to the diets (p 0.05), and improved duodenum and immune functions. However, the results above were not significantly different between birds fed 0.1% Bacillus subtilis natto supplemented diets and the control group (p>0.05). The results of the present study indicate that diets with 0.4% Bacillus subtilis natto improved the growth performance of Muscovy ducks by increasing the absorption of protein, simulating hormone secretion, suppressing harmful microflora, and improving the duodenal structure and immune functions of Muscovy ducks. It is suggested that Bacillus subtilis natto is a potential candidate to be used use as a probiotic to improve the growth performance of Muscovy ducks.


Assuntos
Animais , Bacillus subtilis/patogenicidade , Patos/crescimento & desenvolvimento , Patos/microbiologia
10.
R. bras. Ci. avíc. ; 15(3): 191-197, July-Sept. 2013. tab
Artigo em Inglês | VETINDEX | ID: vti-28134

RESUMO

The aim of the present study was to determine whether dietary Bacillus subtilis natto could affect growth performance of Muscovy ducks. A total of 120 hundred Muscovy ducks at the age of 1 day were randomly assigned to four groups (30 Muscovy ducks/group), and fed with diets supplemented with 0% (control group), 0.1%, 0.2%, and 0.4% Bacillus subtilis natto, respectively during the 6-week feeding period. Weight gain, feed intake and feed conversion efficiency of Muscovy ducks were significantly improved by the dietary addition of Bacillus subtilis natto, and the results were more significant in 0.4% dietary Bacillus subtilis natto treatment group; Also, Bacillus subtilis natto reduced Escherichia coli and Salmonella colonies, and increased lactobacilli population in the ileum and the cecum. Biochemical parameters, including total protein, GOT (glutamic oxaloacetic transaminase), GPT (glutamic pyruvic transaminase), AKP (alkaline phosphatase), triiodothyronine (T3) and tetraiodothyronine (T4) contents (pBacillus subtilis natto was added to the diets (p 0.05), and improved duodenum and immune functions. However, the results above were not significantly different between birds fed 0.1% Bacillus subtilis natto supplemented diets and the control group (p>0.05). The results of the present study indicate that diets with 0.4% Bacillus subtilis natto improved the growth performance of Muscovy ducks by increasing the absorption of protein, simulating hormone secretion, suppressing harmful microflora, and improving the duodenal structure and immune functions of Muscovy ducks. It is suggested that Bacillus subtilis natto is a potential candidate to be used use as a probiotic to improve the growth performance of Muscovy ducks.(AU)


Assuntos
Animais , Patos/crescimento & desenvolvimento , Patos/microbiologia , Bacillus subtilis/patogenicidade
11.
Braz J Med Biol Res ; 46(5): 460-4, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23797494

RESUMO

Melanocyte loss in vitiligo vulgaris is believed to be an autoimmune process. Macrophage migration inhibitory factor (MIF) is involved in many autoimmune skin diseases. We determined the possible role of MIF in the pathogenesis of vitiligo vulgaris, and describe the relationship between MIF expressions and disease severity and activity. Serum MIF concentrations and mRNA levels in PBMCs were measured in 44 vitiligo vulgaris patients and 32 normal controls, using ELISA and real-time RT-PCR. Skin biopsies from 15 patients and 6 controls were analyzed by real-time RT-PCR. Values are reported as median (25th-75th percentile). Serum MIF concentrations were significantly increased in patients [35.81 (10.98-43.66) ng/mL] compared to controls [7.69 (6.01-9.03) ng/mL]. MIF mRNA levels were significantly higher in PBMCs from patients [7.17 (3.59-8.87)] than controls [1.67 (1.23-2.42)]. There was also a significant difference in MIF mRNA levels in PBMCs between progressive and stable patients [7.86 (5.85-9.13) vs 4.33 (2.23-8.39)] and in serum MIF concentrations [40.47 (27.71-46.79) vs 26.80 (10.55-36.07) ng/mL]. In addition, the vitiligo area severity index scores of patients correlated positively with changes of both serum MIF concentrations (r = 0.488) and MIF mRNA levels in PBMCs (r = 0.426). MIF mRNA levels were significantly higher in lesional than in normal skin [2.43 (2.13-7.59) vs 1.18 (0.94-1.83)] and in patients in the progressive stage than in the stable stage [7.52 (2.43-8.84) vs 2.13 (1.98-2.64)]. These correlations suggest that MIF participates in the pathogenesis of vitiligo vulgaris and may be useful as an index of disease severity and activity.


Assuntos
Leucócitos Mononucleares/química , Fatores Inibidores da Migração de Macrófagos/metabolismo , RNA Mensageiro/metabolismo , Vitiligo/metabolismo , Adolescente , Adulto , Estudos de Casos e Controles , ELISPOT , Feminino , Humanos , Fatores Inibidores da Migração de Macrófagos/análise , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Índice de Gravidade de Doença , Vitiligo/etiologia , Vitiligo/patologia , Adulto Jovem
12.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;46(5): 460-464, maio 2013. graf
Artigo em Inglês | LILACS | ID: lil-675671

RESUMO

Melanocyte loss in vitiligo vulgaris is believed to be an autoimmune process. Macrophage migration inhibitory factor (MIF) is involved in many autoimmune skin diseases. We determined the possible role of MIF in the pathogenesis of vitiligo vulgaris, and describe the relationship between MIF expressions and disease severity and activity. Serum MIF concentrations and mRNA levels in PBMCs were measured in 44 vitiligo vulgaris patients and 32 normal controls, using ELISA and real-time RT-PCR. Skin biopsies from 15 patients and 6 controls were analyzed by real-time RT-PCR. Values are reported as median (25th-75th percentile). Serum MIF concentrations were significantly increased in patients [35.81 (10.98-43.66) ng/mL] compared to controls [7.69 (6.01-9.03) ng/mL]. MIF mRNA levels were significantly higher in PBMCs from patients [7.17 (3.59-8.87)] than controls [1.67 (1.23-2.42)]. There was also a significant difference in MIF mRNA levels in PBMCs between progressive and stable patients [7.86 (5.85-9.13) vs 4.33 (2.23-8.39)] and in serum MIF concentrations [40.47 (27.71-46.79) vs 26.80 (10.55-36.07) ng/mL]. In addition, the vitiligo area severity index scores of patients correlated positively with changes of both serum MIF concentrations (r = 0.488) and MIF mRNA levels in PBMCs (r = 0.426). MIF mRNA levels were significantly higher in lesional than in normal skin [2.43 (2.13-7.59) vs 1.18 (0.94-1.83)] and in patients in the progressive stage than in the stable stage [7.52 (2.43-8.84) vs 2.13 (1.98-2.64)]. These correlations suggest that MIF participates in the pathogenesis of vitiligo vulgaris and may be useful as an index of disease severity and activity.


Assuntos
Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Leucócitos Mononucleares/química , Fatores Inibidores da Migração de Macrófagos/metabolismo , RNA Mensageiro/metabolismo , Vitiligo/metabolismo , Estudos de Casos e Controles , ELISPOT , Fatores Inibidores da Migração de Macrófagos/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Índice de Gravidade de Doença , Vitiligo/etiologia , Vitiligo/patologia
13.
Artigo em Inglês | VETINDEX | ID: vti-759611

RESUMO

The aim of the present study was to determine whether dietary Bacillus subtilis natto could affect growth performance of Muscovy ducks. A total of 120 hundred Muscovy ducks at the age of 1 day were randomly assigned to four groups (30 Muscovy ducks/group), and fed with diets supplemented with 0% (control group), 0.1%, 0.2%, and 0.4% Bacillus subtilis natto, respectively during the 6-week feeding period. Weight gain, feed intake and feed conversion efficiency of Muscovy ducks were significantly improved by the dietary addition of Bacillus subtilis natto, and the results were more significant in 0.4% dietary Bacillus subtilis natto treatment group; Also, Bacillus subtilis natto reduced Escherichia coli and Salmonella colonies, and increased lactobacilli population in the ileum and the cecum. Biochemical parameters, including total protein, GOT (glutamic oxaloacetic transaminase), GPT (glutamic pyruvic transaminase), AKP (alkaline phosphatase), triiodothyronine (T3) and tetraiodothyronine (T4) contents (pBacillus subtilis natto was added to the diets (p 0.05), and improved duodenum and immune functions. However, the results above were not significantly different between birds fed 0.1% Bacillus subtilis natto supplemented diets and the control group (p>0.05). The results of the present study indicate that diets with 0.4% Bacillus subtilis natto improved the growth performance of Muscovy ducks by increasing the absorption of protein, simulating hormone secretion, suppressing harmful microflora, and improving the duodenal structure and immune functions of Muscovy ducks. It is suggested that Bacillus subtilis natto is a potential candidate to be used use as a probiotic to improve the growth performance of Muscovy ducks.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA