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1.
Chem Commun (Camb) ; 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32578604

RESUMO

A one-dimensional Cd0.6Zn0.4S nanorod (CZS NR) solid solution with rich sulfur vacancies achieved an excellent photocatalytic hydrogen production activity of 59.3 mmol h-1 g-1 under visible irradiation, which is the highest number observed for CdZnS solid solution nanomaterials to date.

2.
Stem Cell Res Ther ; 11(1): 163, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32345350

RESUMO

BACKGROUND: Human embryonic stem cells represent a potentially unlimited source of insulin-producing cells for diabetes therapy. While tremendous progress has been made in directed differentiation of human embryonic stem cells into IPCs in vitro, the mechanisms controlling its differentiation and function are not fully understood. Previous studies revealed that lysine-specific demethylase 1(LSD1) balanced the self-renewal and differentiation in human induced pluripotent stem cells and human embryonic stem cells. This study aims to explore the role of LSD1 in directed differentiation of human embryonic stem cells into insulin-producing cells. METHODS: Human embryonic stem cell line H9 was induced into insulin-producing cells by a four-step differentiation protocol. Lentivirus transfection was applied to knockdown LSD1 expression. Immunofluorescence assay and flow cytometry were utilized to check differentiation efficiency. Western blot was used to examine signaling pathway proteins and differentiation-associated proteins. Insulin/C-peptide release was assayed by ELISA. Statistical analysis between groups was carried out with one-way ANOVA tests or a student's t test when appropriate. RESULTS: Inhibition or silencing LSD1 promotes the specification of pancreatic progenitors and finally the commitment of functional insulin-producing ß cells; Moreover, inhibition or silencing LSD1 activated ERK signaling and upregulated pancreatic progenitor associated genes, accelerating pre-maturation of pancreatic progenitors, and conferred the NKX6.1+ population with better proliferation ability. IPCs with LSD1 inhibitor tranylcypromine treatment displayed enhanced insulin secretion in response to glucose stimulation. CONCLUSIONS: We identify a novel role of LSD1 inhibition in promoting IPCs differentiation from hESCs, which would be emerged as potential intervention for generation of functional pancreatic ß cells to cure diabetes.

3.
Food Funct ; 11(3): 2380-2394, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32129350

RESUMO

Lutein, as a natural nutrient, has many benefits for human health. However, its poor chemical stability and low bioavailability limit the application of lutein in foods. The aim of this study is to design and develop rice protease hydrolysate (RPH)-carboxymethylcellulose (CMC) nanocarriers for efficient delivery of lutein. RPH-CMC nanoparticles were prepared by heating at a ratio of RPH to CMC of 4 : 1 and pH of 6.0 (70 °C, 20 min). The structure of the nanoparticles was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and transmission electron microscopy (TEM). In addition, the stability, in vitro release characteristics, anti-proliferation and drug absorption of lutein-loaded rice protein nanoparticles (Lut-R) and lutein-loaded CMC-RPH nanoparticles (Lut-R-C) were evaluated. The results of in vitro release showed that compared with Lut-R, Lut-R-C could effectively slow down the release of lutein in the stomach (19.55 ± 1.71% and 8.10 ± 0.41%) and accelerate its release after entering the small intestine (76.64 ± 1.47% and 96.07 ± 0.71%). In addition, RPH-CMC nanoparticles had good biocompatibility, and Lut-R-C nanoparticles could effectively inhibit the proliferation of breast cancer cells (MCF-7) with inhibition rate of 70% in a dose-dependent manner when lutein concentration was 20 µM. It was found that lutein uptake rate and amount in Lut-R-C treated cells were always higher than that in Lut-R treated cells. The absorption of Lut-R-C by Caco-2 cells was 90.8 times higher than that of Lut-R cells at 3 h. This study provides a new idea for improving the application of lutein in foods.

4.
World J Clin Cases ; 7(18): 2712-2721, 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31616687

RESUMO

BACKGROUND: Radical gastrectomy with D2 lymph node (LN) dissection is the standard surgical procedure for patients with resectable gastric cancer (GC). In the fifteenth edition of the Japanese Classification of Gastric Carcinoma, the 14v LN (LNs along the root of the superior mesenteric vein) was defined as the regional gastric LN. The efficacy of 14v LN dissection during radical distal gastrectomy for lower-third GC remains controversial. AIM: To analyze whether the addition of 14v LN dissection improved the survival of patients with lower-third GC. METHODS: The data from 65 patients who underwent 14v LN dissection and 65 patients treated without 14v LN dissection were selected using the propensity score-matched method from our institute database constructed between 2000 and 2012. Overall survival was compared between the groups. RESULTS: Overall survival was similar between patients with 14v LN metastasis and those with distant metastasis (P = 0.521). Among patients with pathological stage IIIA disease, those who were treated with 14v LN dissection had a significantly higher overall survival than those treated without it (P = 0.020). Multivariate analysis showed that age < 65 years and pT2-3 stage were independent favorable prognostic factors for prolonged overall survival in patients with pathological stage IIIA disease. Patients with No. 1, No. 6, No. 8a, or No. 11p LN metastasis were at higher risk of having 14v LN metastasis. CONCLUSION: Adding 14v LN dissection to D2 dissection during radical distal gastrectomy may improve the overall survival of patients with pathological stage IIIA lower-third GC.

5.
Adv Mater ; 31(50): e1901414, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31456280

RESUMO

Potassium-ion batteries (KIBs) are a core energy storage device that can meet the need for scalable and affordable stationary applications because they use low-cost and earth-abundant potassium. In addition, KIB shares a similar storage mechanism with current Li-ion batteries. As the key to optimizing a battery's performance, the development of high-performance electrode materials helps to increase the feasibility of KIB technology. In this sense, phosphorus-based materials (i.e., phosphorus and metal phosphide) with high theoretical capacity and low redox potential tick all the right boxes as a material of choice. A rapid glimpse at recent studies on phosphorus-based anode materials for advanced KIBs is provided, covering the synthetic methods, reaction mechanisms, electrochemical properties, and performances. In addition, several promising strategies are highlighted to address the imminent challenges faced by phosphorus-based anode materials, hoping to cast an insightful outlook for possible future direction in this field.

6.
Biomed Pharmacother ; 107: 1093-1103, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30257321

RESUMO

BACKGROUND: As an inorganic compound used to treat various cancers and other diseases, arsenic trioxide (As2O3) has been reported to induce cellular apoptosis in certain kinds of cancers including bladder cancer. The aim of the present study was to elucidate the crucial cooperative role of As2O3 and intravesical bacillus Calmette-Guerin (BCG) immunotherapy and its ability to protect against bladder cancer by targeting the IER3/Nrf2 pathway. METHOD: Initially, an orthotopic bladder cancer model was established in mice by means of intravesical instillation of the human bladder cancer cell line 5637. The expression of IL-6/IL-8 in dendritic cells (DCs) and the proportion of CD4+ cells and ratio of CD4+/CD8+ T cells were subsequently determined. RT-qPCR and Western blot assay methods were employed to determine the expressions of IER3, Nrf2, NQO1, IL-6 and IL-8. Finally, tumor cell apoptosis and the volume and weight of the in vivo tumors were evaluated in an attempt to determine the contributory role of As2O3 in combination with BCG immunotherapy in treating bladder cancer. RESULTS: The additive effect of As2O3 and BCG was demonstrated to promote the expressions of IL-6/IL-8 among DCs. Additionally, the proportion of CD4+ cells, ratio of CD4+/CD8+ T cells and rate of tumor cell apoptosis were all elevated, while decreased in vivo tumor volume and weight were detected. Of importance, we determined the role that ad-shNrf2 (adenoviral vectors expressing shRNA against Nrf2) played in inhibiting the effects of As2O3 on bladder cancer. CONCLUSION: Taken together, the key findings of the present study provide evidence defining the effect of As2O3 on inducing the inhibitory effect of BCG on the development of bladder cancer via the IER3/Nrf2 pathway, highlighting the potential of As2O3 as a treatment option for bladder cancer through its enhancement of intravesical BCG.


Assuntos
Trióxido de Arsênio/administração & dosagem , Vacina BCG/administração & dosagem , Imunoterapia/métodos , Neoplasias da Bexiga Urinária/terapia , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/farmacologia , Administração Intravesical , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/imunologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Trióxido de Arsênio/farmacologia , Vacina BCG/imunologia , Western Blotting , Linhagem Celular Tumoral , Sinergismo Farmacológico , Feminino , Humanos , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C3H , Fator 2 Relacionado a NF-E2/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias da Bexiga Urinária/imunologia
7.
Cancer Manag Res ; 10: 2589-2604, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30127645

RESUMO

Purpose: No consensus exists on the impact of polymorphisms in cytokines (such as interleukin IL-8 and IL-18) on cancer risk; moreover, there is very little evidence regarding head and neck cancer (HNC). Methods: Thus, a meta-analysis including 22 studies with 4731 cases and 8736 controls was conducted to evaluate this association. The summary odds ratio (OR) and corresponding 95% confidence intervals (CIs) for C-X-C motif chemokine ligand 8 (CXCL8, which encodes IL-8) and IL-18 polymorphisms and HNC risk were estimated. Results: The results showed a significantly increased risk of HNC susceptibility for IL18 -137 G/C in five genetic models, but, interestingly, no significant association was found for the CXCL8 -251 A/T polymorphism. When stratified by cancer type, an increased risk of nasopharyngeal cancer was found for both -137 G/C and -251A/T. When the studies were stratified by ethnicity and genotyping method, there were significant associations between Asian populations and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) studies for -137 G/C, and African populations for -251 A/T in some genetic models. A positive association was also found between the population-based groups in some models for -137 G/C; conversely, significantly decreased risk was found among the -251 A/T hospital-based group. Meta-regression was also conducted. The publication year, control source, and cancer type contributed to CXCL8 -251 A/T heterogeneity; however, no factors were found that contributed to IL-18 -137 G/C heterogeneity. Marginal significance was found in the recessive model for IL-18 -137 G/C by Egger's test, whereas no publication bias was detected for CXCL8 -251 A/T. Conclusions: The results indicate that the IL-18 -137 G/C polymorphism is associated with HNC risk, especially nasopharyngeal cancer, in Asian populations and, when using PCR-RFLP, CXCL8 -251 A/T polymorphisms play a complex role in HNC development.

8.
Microb Pathog ; 121: 59-64, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29763725

RESUMO

Toll like receptor 4 (TLR4), eosinophils and mast cells play significant role in host immunity during several pathogenic infections. However in vivo tissue expression of TLR4 and distribution pattern of eosinophils and mast cells in chicken bursa of Fabricius (BF) during Salmonella enterica serovar Typhimurium (STm) infection is poorly studied. Therefore, herein, following immunostaining, we found localization of TLR4 in follicular cortex and medulla and its expression was statistical increased after 36 h and 72 h of STm stimulation. Chromotrope 2R staining revealed that eosinophils were mostly distributed in follicular cortex, inter-follicular spaces and in or around blood vessels and their number in BF were statistical increased after 72 h of STm stimulation. The presence of eosinophils was confirmed using immunostaining with anti-rabbit eosinophil cationic protein antibody. Toluidine blue stained mast cells were mostly distributed in connective tissues between inter-follicular spaces while some were also present in follicular cortex of BF. However, STm stimulation illustrated non-significant effect on the number of mast cells or their de-granulation, instead their number were gradually decreased in BF with advancement in age of chickens. Hence, this study provided novel information about in vivo tissue distribution of TLR4, eosinophils and mast cells in BF during STm infection.


Assuntos
Bolsa de Fabricius/citologia , Bolsa de Fabricius/microbiologia , Salmonelose Animal/imunologia , Receptor 4 Toll-Like/metabolismo , Animais , Bolsa de Fabricius/imunologia , Galinhas , Eosinófilos/imunologia , Regulação da Expressão Gênica , Imuno-Histoquímica , Mastócitos/imunologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Salmonella typhimurium , Receptor 4 Toll-Like/genética
9.
BMC Immunol ; 18(1): 12, 2017 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-28241791

RESUMO

BACKGROUND: Lipopolysaccharide (LPS) induces acute liver injury and the complex mechanisms include the activation of toll like receptor 4 (TLR4) signaling pathway in many species. However, immuno-pathological changes during TLR4 signaling under LPS stress in acute liver injury is poorly understood in avian species. The present investigation was therefore carried out to evaluate these alterations in TLR4 signaling pathway during acute liver injury in young chickens. RESULTS: After intraperitoneal injection of LPS or saline, liver samples were harvested at 0, 2, 6, 12, 24, 36, 72 and 120 h (n = 6 at each time point) and the microstructures were analyzed by hematoxylin and eosin (H&E) staining. Alanine aminotransferase (ALT) and caspase-3 enzyme activity was assessed by enzyme-linked immunosorbent assay (ELISA). Proliferative cell nuclear antigen (PCNA), single stranded DNA (ssDNA) and TLR4 protein expressions were determined by immunohistochemistry. Gene expressions of PCNA, caspase-3, caspase-8, TLR4 and its downstream molecules were analyzed by quantitative polymerase chain reaction (qPCR). LPS injection induced significantly higher ALT activity, severe fatty degeneration, necrotic symptoms, ballooning degeneration, congestion, enhanced inflammatory cell infiltration in liver sinusoids, decreased proliferation, increased apoptosis and significant up-regulation in TLR4 and its downstream molecules (MyD88, NF-κB, TNF-α, IL-1ß and TGF-ß) expression at different time points. CONCLUSIONS: This study indicated that TLR4 signaling and its downstream molecules along with certain cytokines play a key role in acute liver injury in young chickens. Hence, our findings provided novel information about the histopathological, proliferative and apoptotic alterations along with changes in ALT and caspase-3 activities associated with acute liver injury induced by Salmonella LPS in avian species.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/imunologia , Galinhas/imunologia , Fígado/imunologia , Salmonella/imunologia , Receptor 4 Toll-Like/metabolismo , Alanina Transaminase/sangue , Animais , Caspase 3/metabolismo , Feminino , Lipopolissacarídeos/imunologia , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
10.
ACS Appl Mater Interfaces ; 9(6): 5231-5236, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28165717

RESUMO

A conjugated microporous polymer (CMP) material was designed with pore function of cyano and pyridyl groups that act as potential binding sites for Ag+ ion capture. Ultrafine silver nanoparticles (less than 5 nm) were successfully supported on the predesigned CMP material to afford Ag0@CMP composite materials by means of a simple liquid impregnation and light-induced reduction method. Spherical Ag0 nanoparticles with a statistical mean diameter of ca. 3.9 nm were observed and characterized by scanning electron microscopy and transmission electron microscopy. The Ag0@CMP composite materials were consequently exploited as high-performance nanocatalysts for the reduction of nitrophenols, a family of priority pollutants, at various temperatures and ambient pressure. Moreover, the composite nanocatalysts feature convenient recovery and excellent reusability. This work presents an efficient platform to achieve ultrafine metal nanoparticles immobilized on porous supports with predominant catalytic properties by virtue of the structural design and spatial confinement effect available for conjugated microporous polymers.

11.
Front Chem ; 5: 123, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29326925

RESUMO

A family of new composite materials was successfully prepared through the deposition of as-synthesized CdS nanomaterials on lotus-seedpod-derived activated carbon (SAC). The SAC supports derived at different activation temperatures exhibited considerably large surface areas and various microstructures that were of great importance in enhancing photocatalytic performance of CdS@SAC composite materials toward the photodegradation of rhodamine B (RhB) under visible irradiation. The best-performing CdS@SAC-800 showed excellent photocatalytic activity with a rate constant of ca. 2.40 × 10-2 min-1, which was approximately 13 times higher than that of the CdS nanomaterials. Moreover, the estimated band gap energy of CdS@SAC-800 was significantly lowered down to 1.99 eV compared to that of the CdS precursor (2.22 eV), which suggested considerable strength of interface contact between the CdS and SAC support, as well as efficient light harvesting capacity of the composite material. Further photocatalytic study indicated that the SAC supports enhanced the separation of photogenerated electrons and holes in this system. Improved photocatalytic activity of the composite materials was largely due to the increased generation of catalytically active species such as h+, OH•, [Formula: see text] etc. This work provided a facile and low-cost pathway to fabricate photocatalysts for viable degradation of organic dye molecules.

12.
Oncotarget ; 8(65): 108375-108391, 2017 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-29312537

RESUMO

We investigated the mechanisms that induce atrophy of the chicken bursa of Fabricius (BF) upon lipopolysaccharide (LPS) treatment in young chicks. LPS treatment resulted in ∼36% decrease in bursal weight within 36 h (P < 0.01). Histological analysis showed infiltration of eosinophilic heterophils and nucleated oval shaped RBCs in or near blood vessels of the BF from LPS-treated chicks. Scanning electron micrographs showed severe erosion and breaks in the mucosal membrane at 12 h and complete exuviation of bursal mucosal epithelial cells at 36 h. We observed decreased cell proliferation (low PCNA positivity) and increased apoptosis (high TUNEL and ssDNA positivity) in the BF 12-72 h after LPS treatment. RNA-seq analysis of the BF transcriptome showed 736 differentially expressed genes with most expression changes (637/736) 12 h after LPS treatment. KEGG pathway analysis identified TLR4-MAPK-NF-κB/AP-1 as the key signaling pathway affected in response to LPS stimulation. These findings indicate LPS activates the TLR4-MAPK-NF-κB/AP-1 signaling pathway that mediates acute atrophy of the chicken bursa of Fabricius by inducing inflammation and apoptosis.

13.
Avian Pathol ; 45(5): 530-7, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27009347

RESUMO

Endotoxin or lipopolysaccharide (LPS) exposure can cause injury to the respiratory airways and in response, the respiratory epithelia express toll-like receptors (TLRs) in many species. However, its role in the innate immunity in the avian respiratory system is poorly understood. The aim of the present study was to evaluate the effects of LPS on the chicken trachea and lung. After intraperitoneal LPS or saline injection, the trachea and lungs were harvested at 0, 12, 36 and 72 h (n = 6 at each time point) and histopathologically analysed using haematoxylin and eosin and periodic acid-Schiff staining, while TLR4 expression was determined by immunohistochemistry and secretory Immunoglobulin A (SIgA) levels by enzyme-linked immunosorbent assay. After LPS stimulation, we observed a remarkable decrease in the number of goblet cells along with obvious disruption and desquamation of the ciliated epithelium in the trachea, blurring of the boundary between pulmonary lobules, narrowed or indistinguishable lumen of the pulmonary atria and leukostasis in the lungs. Following LPS stimulation, TLR4 protein expression was up-regulated in both the trachea and the lungs and was found on the ciliated columnar cells as well as in the submucosa of the trachea, and in the lungs on parenchymal and immune cells. However, SIgA levels were only up-regulated in the trachea at 12 h following LPS stimulation. Hence, this report provides novel information about the effects of LPS on the microstructure of the lower respiratory tract and it is concluded that its intra-peritoneal administration leads to TLR4-mediated destruction of the tracheal epithelium and pulmonary inflammation along with increased SIgA expression in the tracheal mucosa.


Assuntos
Galinhas/imunologia , Regulação da Expressão Gênica/efeitos dos fármacos , Lipopolissacarídeos/efeitos adversos , Receptor 4 Toll-Like/efeitos dos fármacos , Animais , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Células Caliciformes/efeitos dos fármacos , Células Caliciformes/patologia , Imunoglobulina A Secretora/efeitos dos fármacos , Imunoglobulina A Secretora/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/patologia , Distribuição Aleatória , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/patologia , Receptor 4 Toll-Like/metabolismo , Traqueia/efeitos dos fármacos , Traqueia/patologia , Regulação para Cima/efeitos dos fármacos
14.
Nanoscale ; 8(21): 10928-37, 2016 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-26864500

RESUMO

Engineering hierarchical structures of electrode materials is a powerful strategy for optimizing the electrochemical performance of an anode material for lithium-ion batteries (LIBs). Herein, we report the fabrication of hierarchical TiO2/C nanocomposite monoliths by mediated mineralization and carbonization using bacterial cellulose (BC) as a scaffolding template as well as a carbon source. TiO2/C has a robust scaffolding architecture, a mesopore-macropore network and TiO2-C heterostructure. TiO2/C-500, obtained by calcination at 500 °C in nitrogen, contains an anatase TiO2-C heterostructure with a specific surface area of 66.5 m(2) g(-1). When evaluated as an anode material at 0.5 C, TiO2/C-500 exhibits a high and reversible lithium storage capacity of 188 mA h g(-1), an excellent initial capacity of 283 mA h g(-1), a long cycle life with a 94% coulombic efficiency preserved after 200 cycles, and a very low charge transfer resistance. The superior electrochemical performance of TiO2/C-500 is attributed to the synergistic effect of high electrical conductivity, anatase TiO2-C heterostructure, mesopore-macropore network and robust scaffolding architecture. The current material strategy affords a general approach for the design of complex inorganic nanocomposites with structural stability, and tunable and interconnected hierarchical porosity that may lead to the next generation of electrochemical supercapacitors with high energy efficiency and superior power density.

15.
Neural Regen Res ; 11(11): 1779-1783, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28123420

RESUMO

Proanthocyanidins have been shown to effectively protect ischemic neurons, but its mechanism remains poorly understood. Ginkgo proanthocyanidins (20, 40, 80 mg/kg) were intraperitoneally administered 1, 24, 48 and 72 hours before reperfusion. Results showed that ginkgo proanthocyanidins could effectively mitigate neurological disorders, shorten infarct volume, increase superoxide dismutase activity, and decrease malondialdehyde and nitric oxide contents. Simultaneously, the study on grape seed proanthocyanidins (40 mg/kg) confirmed that different sources of proanthocyanidins have a similar effect. The neurological outcomes of ginkgo proanthocyanidins were similar to that of nimodipine in the treatment of cerebral ischemia/reperfusion injury. Our results suggest that ginkgo proanthocyanidins can effectively lessen cerebral ischemia/reperfusion injury and protect ischemic brain tissue and these effects are associated with antioxidant properties.

16.
Vet Immunol Immunopathol ; 166(3-4): 145-50, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26049167

RESUMO

Toll-like receptors (TLRs) play crucial roles in innate and adaptive immune responses to invading pathogens. TLR4 is responsible for the recognition of bacterial lipopolysaccharide (LPS) in different parts of central nervous system of many vertebrates. To better understand the functions of TLR4 in cerebellum of chicken, present study was designed to identify the cell types that express TLR4 during postnatal stages as well as the changes in its expression in response to LPS challenge. For this purpose, cerebella were collected from chicken aged 1, 14 and 40 days (n=7 in each group) to analyze TLR4 distribution pattern. The cerebella from 14 chickens injected with LPS or sterilizing saline were also collected at Day 14 (n=7 in each group) to investigate changes in TLR4 expression. This expression was analyzed by immunohistochemistry using an anti-TLR4 antibody. TLR4 was constitutively expressed in the Purkinje cell layer, pia mater, neurons in medulla and blood vessels in the cerebellum and LPS stimulation significantly up-regulated TLR4 expression on Day 14 in the chicken cerebellum. This study provides evidence that neurons in chicken cerebellum can express TLR4 in vivo and suggests that these neurons may play an important role in initiating a defense reaction via activation of TLR4.


Assuntos
Cerebelo/metabolismo , Lipopolissacarídeos/farmacologia , Receptor 4 Toll-Like/biossíntese , Fatores Etários , Animais , Cerebelo/química , Cerebelo/efeitos dos fármacos , Galinhas/imunologia , Receptor 4 Toll-Like/análise , Regulação para Cima
17.
PLoS One ; 10(6): e0129596, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26053067

RESUMO

Previous studies revealed that thymus is a targeted immune organ in malnutrition, and high-boron stress is harmful for immune organs. African ostrich is the living fossil of ancient birds and the food animals in modern life. There is no report about the effect of boron intake on thymus of ostrich. The purpose of present study was to evaluate the effect of excessive boron stress on ostrich thymus and the potential role of TLR3/4 signals in this process. Histological analysis demonstrated that long-term boron stress (640 mg/L for 90 days) did not disrupt ostrich thymic structure during postnatal development. However, the numbers of apoptotic cells showed an increased tendency, and the expression of autophagy and proliferation markers increased significantly in ostrich thymus after boron treatment. Next, we examined the expression of TLR3 and TLR4 with their downstream molecular in thymus under boron stress. Since ostrich genome was not available when we started the research, we first cloned ostrich TLR3 TLR4 cDNA from thymus. Ostrich TLR4 was close to white-throated Tinamou. Whole avian TLR4 codons were under purify selection during evolution, whereas 80 codons were under positive selection. TLR3 and TLR4 were expressed in ostrich thymus and bursa of fabricius as was revealed by quantitative real-time PCR (qRT-PCR). TLR4 expression increased with age but significantly decreased after boron treatment, whereas TLR3 expression showed the similar tendency. Their downstream molecular factors (IRF1, JNK, ERK, p38, IL-6 and IFN) did not change significantly in thymus, except that p100 was significantly increased under boron stress when analyzed by qRT-PCR or western blot. Taken together, these results suggest that ostrich thymus developed resistance against long-term excessive boron stress, possibly by accelerating intrathymic cell death and proliferation, which may bypass the TLR3/4 pathway. In addition, attenuated TLRs activity may explain the reduced inflammatory response to pathogens under boron stress.


Assuntos
Aves/fisiologia , Boro/metabolismo , Transdução de Sinais , Estresse Fisiológico , Timo/citologia , Receptor 3 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Sequência de Aminoácidos , Animais , Apoptose/genética , Autofagia/genética , Sequência de Bases , Proliferação de Células , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , Evolução Molecular , Expressão Gênica , Dados de Sequência Molecular , Filogenia , Timo/fisiologia , Receptor 3 Toll-Like/genética , Receptor 4 Toll-Like/genética
18.
Vet Immunol Immunopathol ; 158(3-4): 182-8, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24507560

RESUMO

Toll-like receptor 4 (TLR4) has been suggested to play a regulatory role in immune cell development; however, studies regarding the role of TLR4 in the development of the chick thymus are scarce. In this study, we investigated the distribution and expression pattern of TLR4 in normal chick thymi at different stages of development, in order to better understand the role of TLR4 in chick thymus development. We studied the thymi from 15 chicks, collected at days 7, 21 and 35 of age. The relative change in TLR4 mRNA expression in the chick thymus at different ages was determined by quantitative real-time PCR, and changes in protein expression were analyzed by immunohistochemistry and Western blotting. Furthermore, the distribution of TLR4 in the chick thymus was analyzed by immunohistochemistry, and compared with the distribution of TLR4 expression in juvenile female pigs (gilts). Our results indicated that TLR4 was constitutively expressed in the chick thymus. TLR4 was primarily expressed in the thymic cortico-medullary junction and the medulla, particularly in the epithelial cells of Hassall's corpuscles. The mRNA and protein expression level of TLR4 increased in the thymus with increasing age (p<0.05). Taken together, these results indicate that TLR4 is constitutively expressed by epithelial cells in the chick thymus, suggesting it may participate in thymic development by inducing factors affecting its development.


Assuntos
Proteínas Aviárias/imunologia , Proteínas Aviárias/metabolismo , Timo/crescimento & desenvolvimento , Timo/imunologia , Receptor 4 Toll-Like/metabolismo , Animais , Proteínas Aviárias/genética , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Imuno-Histoquímica , Queratinas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Especificidade da Espécie , Sus scrofa/genética , Sus scrofa/imunologia , Timo/citologia , Receptor 4 Toll-Like/genética
19.
Artigo em Inglês | MEDLINE | ID: mdl-23410454

RESUMO

In this paper, a scheme for specifying contact angle and its hysteresis is incorporated into a multiphase lattice Boltzmann method. The scheme is validated through investigations of the dynamic behaviors of a droplet sliding along two kinds of walls: a smooth (ideal) wall and a rough or chemically inhomogeneous (nonideal) wall. For an ideal wall, the wettability of solid substrates is able to be prescribed. For a nonideal wall, arbitrary contact angle hysteresis can be obtained through adjusting advancing and receding angles. Significantly different phenomena can be recovered for the two kinds of walls. For instance, a droplet on an inclined ideal wall under gravity is impossible to stay stationary. However, the droplet on a nonideal wall may be pinned due to contact angle hysteresis. The steady interface shapes of the droplet on an inclined nonideal wall under gravity or in a shear flow quantitatively agree well with the previous numerical studies. Besides, the complex motion of a droplet creeping like an inchworm could be simulated. The scheme is found suitable for the study of contact line problems with and without contact angle hysteresis.


Assuntos
Algoritmos , Modelos Teóricos , Análise Numérica Assistida por Computador , Reologia/métodos , Simulação por Computador
20.
Vet Immunol Immunopathol ; 153(1-2): 123-7, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23333191

RESUMO

Eosinophils are a type of thymic stromal cell that are present in the thymus of both humans and mice. They participate in regulating T-cell development under non-pathological conditions. However, studies are scarce regarding the role of eosinophils in the development of the thymus in chickens. Therefore, this study investigated the distribution of eosinophils in normal chicken thymi at different stages of development. Seven thymi were obtained from chickens at days 1, 21 and 35 of development. The distribution of eosinophils in the thymi was analyzed by histological and immunohistochemical techniques using Lendrum's chromotrope 2R method and an antibody against eosinophilic cationic protein (ECP), respectively. Eosinophils were constitutively located in the chick thymus. They were mainly distributed in the thymic corticomedullary junction and medulla, especially around vessels and Hassall's corpuscles, and only a few were in the trabeculae among thymic lobules and around vessels. There were none in the cortex. The number of thymic eosinophils decreased with increasing age (P<0.01). These results indicated that eosinophils comprise a type of thymic stromal cells in the chick, which may regulate thymic development, especially during the early stages of development.


Assuntos
Galinhas/imunologia , Eosinófilos/fisiologia , Timo/citologia , Fatores Etários , Animais , Galinhas/crescimento & desenvolvimento , Contagem de Leucócitos , Células Estromais/fisiologia , Timo/crescimento & desenvolvimento
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