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1.
FASEB J ; 38(5): e23529, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38441524

RESUMO

γδ T cells are becoming increasingly popular because of their attractive potential for antitumor immunotherapy. However, the role and assessment of γδ T cells in head and neck squamous cell carcinoma (HNSCC) are not well understood. We aimed to explore the prognostic value of γδ T cell and predict its abundance using a radiomics model. Computer tomography images with corresponding gene expression data and clinicopathological data were obtained from online databases. After outlining the volumes of interest manually, the radiomic features were screened using maximum melevance minimum redundancy and recursive feature elimination algorithms. A radiomics model was developed to predict γδ T-cell abundance using gradient boosting machine. Kaplan-Meier survival curves and univariate and multivariate Cox regression analyses were used for the survival analysis. In this study, we confirmed that γδ T-cell abundance was an independent predictor of favorable overall survival (OS) in patients with HNSCC. Moreover, a radiomics model was built to predict the γδ T-cell abundance level (the areas under the operating characteristic curves of 0.847 and 0.798 in the training and validation sets, respectively). The calibration and decision curves analysis demonstrated the fitness of the model. The high radiomic score was an independent protective factor for OS. Our results indicated that γδ T-cell abundance was a promising prognostic predictor in HNSCC, and the radiomics model could discriminate its abundance levels and predict OS. The noninvasive radiomics model provided a potentially powerful prediction tool to aid clinical judgment and antitumor immunotherapy.


Assuntos
Neoplasias de Cabeça e Pescoço , Radiômica , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Algoritmos , Calibragem , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem
2.
BMC Genomics ; 25(1): 394, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649832

RESUMO

BACKGROUND: Untargeted metabolomics and proteomics were employed to investigate the intracellular response of yak rumen epithelial cells (YRECs) to conditions mimicking subacute rumen acidosis (SARA) etiology, including exposure to short-chain fatty acids (SCFA), low pH5.5 (Acid), and lipopolysaccharide (LPS) exposure for 24 h. RESULTS: These treatments significantly altered the cellular morphology of YRECs. Metabolomic analysis identified significant perturbations with SCFA, Acid and LPS treatment affecting 259, 245 and 196 metabolites (VIP > 1, P < 0.05, and fold change (FC) ≥ 1.5 or FC ≤ 0.667). Proteomic analysis revealed that treatment with SCFA, Acid, and LPS resulted in differential expression of 1251, 1396, and 242 proteins, respectively (FC ≥ 1.2 or ≤ 0.83, P < 0.05, FDR < 1%). Treatment with SCFA induced elevated levels of metabolites involved in purine metabolism, glutathione metabolism, and arginine biosynthesis, and dysregulated proteins associated with actin cytoskeleton organization and ribosome pathways. Furthermore, SCFA reduced the number, morphology, and functionality of mitochondria, leading to oxidative damage and inhibition of cell survival. Gene expression analysis revealed a decrease the genes expression of the cytoskeleton and cell cycle, while the genes expression associated with inflammation and autophagy increased (P < 0.05). Acid exposure altered metabolites related to purine metabolism, and affected proteins associated with complement and coagulation cascades and RNA degradation. Acid also leads to mitochondrial dysfunction, alterations in mitochondrial integrity, and reduced ATP generation. It also causes actin filaments to change from filamentous to punctate, affecting cellular cytoskeletal function, and increases inflammation-related molecules, indicating the promotion of inflammatory responses and cellular damage (P < 0.05). LPS treatment induced differential expression of proteins involved in the TNF signaling pathway and cytokine-cytokine receptor interaction, accompanied by alterations in metabolites associated with arachidonic acid metabolism and MAPK signaling (P < 0.05). The inflammatory response and activation of signaling pathways induced by LPS treatment were also confirmed through protein interaction network analysis. The integrated analysis reveals co-enrichment of proteins and metabolites in cellular signaling and metabolic pathways. CONCLUSIONS: In summary, this study contributes to a comprehensive understanding of the detrimental effects of SARA-associated factors on YRECs, elucidating their molecular mechanisms and providing potential therapeutic targets for mitigating SARA.


Assuntos
Acidose , Proliferação de Células , Células Epiteliais , Metabolômica , Proteômica , Rúmen , Animais , Rúmen/metabolismo , Rúmen/efeitos dos fármacos , Acidose/veterinária , Acidose/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Bovinos , Proliferação de Células/efeitos dos fármacos , Ácidos Graxos Voláteis/metabolismo , Lipopolissacarídeos , Doenças dos Bovinos/metabolismo , Proteoma/metabolismo
3.
J Dairy Sci ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38395405

RESUMO

Live body weight (LBW) is one of the most important parameters for supervising the growth and development of livestock. The yak (Bos grunniens) is a special species of cattle that lives on the Qinghai-Tibetan Plateau. Yaks are more untamed than regular cattle breeds, thus it is more challenging to measure their LBW. In this study, a YOLOv8 yak detection and LBW estimation models were used to automatically estimate yak LBW in real-time. First, the proper posture (normal posture) and individual yak identification was confirmed and then the YOLOv8 detection model was used for LBW estimation from 2-dimensional (2D) images. Yak LBW was estimated through yak body parameter extraction and a simple linear regression between the estimated yak LBW and the actual measured yak LBW. The results showed that the overall detection performance of yak normal yak posture was described by precision, recall, and mean Average Precision 50 (mAP50) indicators, reaching 81.8, 86.0, and 90.6%, respectively. The best yak identification results were represented by precision, recall, and mAP50 values of 97.8, 96.4, and 99.0%, respectively. The yak LBW estimation model achieved better results for the 12 mo old yaks with shorter hair with R2, root mean square error (RMSE), mean absolute percentage error (MAPE), and Multiple R values of 0.96, 2.43 kg, 1.69%, and 0.98, respectively. The results demonstrate that yak LBW can be estimated and monitored in real-time using this approach. This study has the potential to be used for daily yak LBW monitoring in an unstressed manner and to save considerable labor resources for large-scale livestock farms. In the future, to reduce the limitations caused by the impacts of yak hair and light condition data sets of dairy cows and yaks of different ages will be used to improve and generalize the model.

4.
Langmuir ; 39(37): 13068-13075, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37678181

RESUMO

We present a facile chemical method for fabricating bioinspired microadhesives with significant improved reversible adhesion strength. Four kinds of polysiloxane with gradient varying phenyl contents were synthesized and used to fabricate microadhesives. The chemical structures and mechanical properties, as well as surface properties of the four microadhesives, were confirmed and characterized by ATR-FTIR, DSC, XPS, low-field NMR, tensile tests, and SEM, respectively. The macroadhesion test results revealed that phenyl contents showed remarkable and positive impacts on the macroadhesion performance of microadhesives. The pull-off adhesion strength of microadhesives with 90% phenyl content (0.851 N/cm2) was nearly 300% higher than that of pure PDMS (0.309 N/cm2). The macroadhesion mechanism analysis demonstrates that a larger bulk energy dissipation caused by massive π-π interaction, as well as the hydrophobic interaction and van der Waals forces at the interface synergistically resulted in a significant enhancement of the adhesion performance. Our results demonstrate the remarkable impact of chemical structures on the adhesion of microadhesives, and it is conducive to the further improvement of adhesion properties of bioinspired microadhesives.

5.
Neuroendocrinology ; 113(5): 563-576, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36587608

RESUMO

INTRODUCTION: Accumulating evidence indicates that abnormalities in the composition of gastrointestinal (GI) microbiota play a vital role in stress-related disorders. Both human beings and animals perceive stressful events differently, i.e., resilience or susceptibility. However, the role of GI microbiota in stress resilience/susceptibility and the underlying mechanisms remain largely unknown. METHODS AND RESULTS: Sixty male C57BL/6J mice were exposed to 10-day chronic social defeat stress (CSDS), and 28 were found to be resilient to CSDS. We next analyzed microbiota compositions in the cecum using 16S rDNA gene sequencing, which revealed a significant increase in the relative abundance of Lactobacillus at the genus level in the resilient mice. In subsequent experiments, we found that oral administration of a strain of Lactobacillus (Lactobacillus murinus) for 2 weeks attenuated the increased levels of stress-induced corticosterone and anxiety-like behavior in stress-susceptible mice. The mRNA expression of tryptophan hydroxylase 2 (a rate-limiting enzyme in serotonin [5-HT] synthesis) was also significantly increased in the dorsal raphe nucleus (DR) of stress-susceptible mice. CONCLUSIONS: Lactobacillus contributes to stress resilience, and the DR 5-HT system may play an important role during this process. The above results suggest that certain organisms in the GI tract may play an essential role in stress response and be useful in the prevention and treatment of some stress-related psychiatric disorders, such as depression.


Assuntos
Serotonina , Derrota Social , Humanos , Camundongos , Masculino , Animais , Camundongos Endogâmicos C57BL , Estresse Psicológico/metabolismo , Lactobacillus
6.
Macromol Rapid Commun ; 44(18): e2300191, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37329201

RESUMO

The fabrication of self-healing elastomers with high thermal stability for use in extreme thermal conditions such as aerospace remains a major challenge. A strategy for preparing self-healing elastomers with stable covalent bonds and dynamic metal-ligand coordination interactions as crosslinking sites in polydimethylsiloxane (PDMS) is proposed. The added Fe (III) not only serves as the dynamic crosslinking point at room temperature which is crucial for self-healing performance, but also plays a role as free radical scavenging agent at high temperatures. The results show that the PDMS elastomers possessed an initial thermal degradation temperature over 380 °C and a room temperature self-healing efficiency as high as 65.7%. Moreover, the char residue at 800 °C of PDMS elastomer reaches 7.19% in nitrogen atmosphere, and up to 14.02% in air atmosphere by doping a small amount (i.e., 0.3 wt%) of Fe (III), which is remarkable for the self-healing elastomers that contain weak and dynamic bonds with relatively poor thermal stability. This study provides an insight into designing self-healing PDMS-based materials that can be targeted for use as high-temperature thermal protection coatings.


Assuntos
Elastômeros , Siloxanas , Elastômeros/química , Siloxanas/química , Temperatura , Dimetilpolisiloxanos/química
7.
Macromol Rapid Commun ; 44(21): e2300357, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37602657

RESUMO

Lightweight polyimide foams (PIFs) with exceptional thermal resistance and compressive properties are fabricated by heating polyester ammonium salts (PEASs) which are prepared by copolymerizing 4, 4'-diaminobenzanilide (DABA), 4, 4'-diaminodiphenyl methane (MDA) and 3, 3', 4, 4'-benzophenone tetracarboxylic dianhydride (BTDA). Hydrogen bonds are formed between CONH and CO in the PI chains due to the addition of DABA and the melt viscosity of PEAS precursors increase with increasing content of DABA, which is advantageous to bind the foaming gases for cell expansion. The expansion ratio of PEAS precursors is increased from 633% to 1133% when the molar ratio of MDA/DABA is changed from 10:0 to 6:4. The compressive strength and modulus of PIFM9D1 (i.e., the molar ratio of MDA/DABA is 9:1, foam density: 120.8 kg m-3 ) reach as high as 0.59 and 15.0 MPa, respectively. The PIFs possess prominent thermal performance with the initial thermal degradation temperatures (under both nitrogen and air atmosphere) and glass transition temperatures (as assessed by DSC and DMA) exceeding 511 and 292 °C, respectively. The thermal conductivity of PIFs is lower than 0.049 W m-1 K-1 , which exhibits promising applications for serving as high-temperature thermal insulation materials in the fields of aerospace, marine, and nuclear sectors among others.


Assuntos
Acetanilidas , Gases , Proliferação de Células , Força Compressiva
8.
J Dairy Sci ; 106(2): 1351-1359, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36460498

RESUMO

In this study, we aimed to classify 7 cow behavior patterns automatically with an inertial measurement unit (IMU) using a fully convolutional network (FCN) algorithm. Behavioral data of 12 cows were collected by attaching an IMU in a waterproof box on the neck behind the head of each cow. Seven behavior patterns were considered: rub scratching (leg), ruminating-lying, lying, feeding, self-licking, rub scratching (neck), and social licking. To simplify the data and compare classification performance with or without magnetometer data, the 9-axis IMU data were reduced using the square root of the sum of squares to develop 2 datasets. Comparing the classification accuracy of the 3 models using a window size of 64 with 6-axis data and a window size of 128 with both 6-axis and 9-axis data, the best overall accuracy (83.75%) was achieved using the FCN model with a window size of 128 (12.8 s) using all IMU data. This model achieved classification accuracies of 83.2, 96.5, 92.8, 98.1, 82.9, 87.2, and 45.2% for ruminating-lying, lying, feeding, rub scratching (leg), self-licking, rub scratching (neck), and social licking, respectively. As a sequence of varied and intensive movement, the classification accuracy of behavior patterns related to skin disease was lower; better classification of these behavior patterns could be achieved with full IMU data and a larger window size. In the future, additional data will take into account different data types, such as audio and video data, to further enhance performance. In addition, an adaptive sliding window size will be used to improve model performance.


Assuntos
Comportamento Animal , Movimento , Feminino , Bovinos , Animais , Algoritmos , Ingestão de Alimentos
9.
Anim Biotechnol ; 33(6): 1150-1160, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33530818

RESUMO

This study aimed to investigate the effects of active dry yeast (ADY) on growth performance, rumen microbial composition and carcass performance of beef cattle. Thirty-two finishing beef cattle (yak ♂ × cattle-yaks ♀), with an average body weight of 110 ± 12.85 kg, were randomly assigned to one of four treatments: the low plane of nutrition group (control), low plane of nutrition group + ADY 2 g/head daily (ADY2), low plane of nutrition group + ADY 4 g/head daily (ADY4) and the high plane of nutrition group (HPN). Supplementation of ADY increased average daily gain compared to the control group. The neutral detergent fiber and acid detergent fiber apparent digestibility in HPN group was greater than that in control group. The propionic acid concentration in the rumen in ADY2, ADY4, and HPN groups was greater than that in control group. The Simpson and Shannon indexes in control and HPN groups were higher than that in ADY4 group. At the phylum level, the relative abundance of Firmicutes in the HPN group was higher than that in ADY4 group. The relative abundance of Ruminococcaceae UCG-002 in ADY4 group was higher than that in control and HPN groups. In conclusion, supplementation ADY 4 g/head daily shift the rumen microbial composition of beef cattle fed low plane of nutrition to a more similar composition with cattle fed with HPN diet and produce the similar carcass weight with HPN diet.HighlightsThe ADY can improve the utilization of nitrogen and decrease the negative impact on the environment in beef cattle.Cattle fed low plane of nutrition diet supplemented with ADY 4 g/head daily increased growth performance.Supplementation ADY 4 g/head daily in low plane of nutrition diet might be produced comparable carcass weight to HPN diet.


Assuntos
Microbiota , Rúmen , Bovinos , Animais , Rúmen/metabolismo , Saccharomyces cerevisiae , Fermentação , Ração Animal/análise , Detergentes/metabolismo , Dieta/veterinária , Suplementos Nutricionais
10.
Appl Microbiol Biotechnol ; 105(1): 313-325, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33201274

RESUMO

Investigation of the compositional and functional characteristics of the gastrointestinal bacterial community in beef cattle breeds can improve our understanding of the influence of gastrointestinal tract (GIT) regions and host breeds on the bacterial community. In this study, 16S ribosomal RNA (16S rRNA) gene amplicon sequencing was used to characterize the bacterial communities in the rumen, duodenum, jejunum, ileum, caecum, and colon of Xuanhan yellow cattle (XHC) and Simmental crossbred cattle (SXC). The results showed that the diversity of the bacterial population was different in GIT regions of XHC and SXC (P < 0.05). In total, ten bacterial phyla, sixteen bacterial genera, and nine metabolic pathways were identified in the core bacteria. The phyla Firmicutes, Bacteroidetes, and Proteobacteria were predominant, but their proportions were different in GIT regions (P < 0.05). The diversity, structure, and composition of the bacteria in the rumen were similar between the breeds (P > 0.05), and the indices in the intestine showed significant differences (P < 0.05). Moreover, the composition and structure of the bacterial communities in the rumen, small intestine, and large intestine were different regardless of the breed. Thus, the bacterial communities were different among the gastrointestinal regions in each breed, and the bacterial community in the rumen had more stable characteristics than that in the intestine between two breeds. Further studies may focus on the minor microbial communities and the functions of GIT bacteria to better understand gut-microbe interactions. KEY POINTS: • Differences in bacteria among gastrointestinal regions differ in cattle breeds. • Differences between the breeds in the ruminal bacteria are less pronounced than differences in the intestinal bacteria.


Assuntos
Bactérias , Trato Gastrointestinal , Animais , Bactérias/genética , Bovinos , DNA Bacteriano/genética , RNA Ribossômico 16S/genética , Rúmen
11.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 50(1): 90-96, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-34117845

RESUMO

To investigate the expression of xenotropic and polytropic retrovirus receptor 1 () in papillary thyroid cancer (PTC) and its clinical implication. The HPA and UALCAN databases were used to explore the expression of XPR1 in PTC and normal tissues. The cBioPortal database was used to obtain the clinical data of PTC patients and gene expression profile. The correlation of expression with gender,age,sub-types,T stage,N stage,M stage and clinical stage of patients were analyzed. Cox regression was conducted to analysis the factors affecting the prognosis of PTC patients. The mutation of was assessed through cBioPortal database. GO and KEGG analyses were used to explore the related biological pathway of involved in PTC. HPA database analysis showed that XPR1 was highly expressed in PTC tissue compared with normal tissues. UALCAN analysis displayed that expression was significantly higher in PTC tissue compared with normal tissues (<0.01),and the highest and lowest expressions of were observed in tall cell and follicular sub-type of PTC,respectively. The expression of was correlated with age,sub-types,T stage,N stage and disease stage of PTC patients (<0.05 or <0.01),but was not correlated with gender and M stage (all >0.05). Cox regression analysis showed that was an independent prognostic factor of PTC patients (=2.894,<0.05). The cBioPortal database indicated that the mutation appeared in 6% PTC patients; the mutation type mainly was missense and the mutation point was located at the E615K. Enrichment analysis indicated that might affect the PTC progression through involvement in metabolic pathway. is highly expressed in PTC tissues,which is associated with the prognosis of patients. Metabolic pathway associated with might play an important role in PTC progression,indicating that might be a novel biomarker for diagnosis and treatment of PTC.


Assuntos
Receptores Acoplados a Proteínas G/genética , Receptores Virais/genética , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Prognóstico , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Receptor do Retrovírus Politrópico e Xenotrópico
12.
Biochem Biophys Res Commun ; 515(4): 558-564, 2019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31178144

RESUMO

Radioresistance remains the most challenging issue leading to radiotherapy failure in the treatment of non-small cell lung cancer (NSCLC). The nuclear factor IA (NFIA) is associated with tumor response to treatments in many cancers, but its role in NSCLC radioresistance remains unclear. Here, we established two radioresistant NSCLC cell lines, H226R and H460R, by dose-gradient irradiation to investigate the function of NFIA in NSCLC radioresistance. The results showed a dramatically reduced expression of NFIA in radioresistant cells accompanied with elevated phosphorylation of AKT and ERK, when compared with their parental cells. Overexpression of NFIA restored the sensitivity of radioresistant cells to radiation through increased ionizing radiation (IR)-induced apoptosis and DNA damage by downregulating p-AKT and p-ERK, whereas knockdown of NFIA promoted radioresistance of the parental cells. Our findings suggested that NFIA enhanced cell radiosensitivity by downregulating p-AKT and p-ERK in NSCLC. Our study fills a gap in the field of NFIA and radioresistance, and establishes a mechanistic foundation to improve radiotherapy efficiency in NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Neoplasias Pulmonares/metabolismo , Fatores de Transcrição NFI/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Tolerância a Radiação , Apoptose , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Reparo do DNA , Relação Dose-Resposta à Radiação , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Humanos , Aceleradores de Partículas , Fosforilação , Radiação Ionizante , Transdução de Sinais , Raios X
13.
BMC Cancer ; 18(1): 611, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29848294

RESUMO

BACKGROUND: Activation of c-Met, a receptor tyrosine kinase, induces radiation therapy resistance in non-small cell lung cancer (NSCLC). The activated residual of c-Met is located in lipid rafts (Duhon et al. Mol Carcinog 49:739-49, 2010). Therefore, we hypothesized that disturbing the integrity of lipid rafts would restrain the activation of the c-Met protein and reverse radiation resistance in NSCLC. In this study, a series of experiments was performed to test this hypothesis. METHODS: NSCLC A549 and H1993 cells were incubated with methyl-ß-cyclodextrin (MßCD), a lipid raft inhibitor, at different concentrations for 1 h before the cells were X-ray irradiated. The following methods were used: clonogenic (colony-forming) survival assays, flow cytometry (for cell cycle and apoptosis analyses), immunofluorescence microscopy (to show the distribution of proteins in lipid rafts), Western blotting, and biochemical lipid raft isolation (purifying lipid rafts to show the distribution of proteins in lipid rafts). RESULTS: Our results showed that X-ray irradiation induced the aggregation of lipid rafts in A549 cells, activated c-Met and c-Src, and induced c-Met and c-Src clustering to lipid rafts. More importantly, MßCD suppressed the proliferation of A549 and H1993 cells, and the combination of MßCD and radiation resulted in additive increases in A549 and H1993 cell apoptosis. Destroying the integrity of lipid rafts inhibited the aggregation of c-Met and c-Src to lipid rafts and reduced the expression of phosphorylated c-Met and phosphorylated c-Src in lipid rafts. CONCLUSIONS: X-ray irradiation induced the aggregation of lipid rafts and the clustering of c-Met and c-Src to lipid rafts through both lipid raft-dependent and lipid raft-independent mechanisms. The lipid raft-dependent activation of c-Met and its downstream pathways played an important role in the development of radiation resistance in NSCLC cells mediated by c-Met. Further studies are still required to explore the molecular mechanisms of the activation of c-Met and c-Src in lipid rafts induced by radiation.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Microdomínios da Membrana/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Quinases da Família src/metabolismo , Células A549 , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Proteína Tirosina Quinase CSK , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Humanos , Neoplasias Pulmonares/patologia , Microdomínios da Membrana/efeitos dos fármacos , Microdomínios da Membrana/efeitos da radiação , Fosforilação/efeitos dos fármacos , Fosforilação/efeitos da radiação , Tolerância a Radiação/efeitos dos fármacos , Radiossensibilizantes/farmacologia , beta-Ciclodextrinas/farmacologia
14.
Asian-Australas J Anim Sci ; 29(6): 814-22, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26954167

RESUMO

This study was conducted to determine and compare the effects of yeast yeast culture (YC) and vitamin E (VE) supplementation on endotoxin absorption and antioxidant status in lactating dairy goats suffering from heat stress (HS). Three first lactation Saanen dairy goats (body weight 30±1.5 kg) were surgically fitted with indwelling catheters in the portal vein, mesenteric vein and carotid artery, and were randomly assigned to a 3×3 Latin square design. Dietary treatments were the basal diet, and the basal diet supplemented with either 100 IU VE or 30 g YC. Goats were kept in temperature and humidity-controlled room at 35°C from 8:00 to 20:00 and at 24°C from 20:00 till the next morning at 8:00. The relative humidity was kept at 55%. HS increased dairy goats' rectum temperature and respiration frequency (p<0.01). HS reduced plasma flux rate of milk goats (p<0.01), but the plasma flux rate increased when the animal was under the conditions of the thermo-neutral period (p<0.01). The VE supplementation lowered dairy goats' rectum temperature during thermo-neutral period (p<0.01). Meanwhile, no significant differences were observed between the control and YC treatment in rectum temperature and respiration frequency (p>0.05). Dietary supplementation of VE and YC reduced heat stressed dairy goats' endotoxin concentration of the carotid artery and portal vein (p<0.01). However, the endotoxin concentration of the YC treatment was higher than that of the VE treatment (p<0.01). Both VE and YC supplementation decreased heat stressed dairy goats' absorption of endotoxin in portal vein (p<0.01). The endotoxin absorption of YC treatment was higher than the VE treatment (p<0.01). The addition of VE and YC decreased dairy goats' superoxide dismutase (SOD) concentration during HS and the whole experiment period (p<0.01). The addition of VE lowered SOD concentration during thermo-neutral period (p<0.01). Likewise, the addition of VE and YC lowered dairy goats' malonaldehyde (MDA) concentration during HS and the whole experimental period, and the MDA concentration in the VE treatment was lower than the YC treatment (p<0.05). The addition of VE decreased MDA concentration during thermo-neutral period. On the contrast, the addition of VE increased dairy goats total antioxidant potential (TAP) concentration during HS, thermo-neutral and the whole experimental period (p<0.01). The addition of YC increased TAP concentration only during HS period (p<0.01). It is concluded that both VE and YC are useful in alleviating HS of dairy goats by weakening endotoxin absorption and promoting antioxidant capacity. Compared with YC, VE is much more powerful in easing dairy goats HS.

15.
Tumour Biol ; 35(3): 2343-50, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24146281

RESUMO

The association between the polymorphism of catechol-O-methyltransferase (COMT) Val158Met and breast cancer risk is still inconclusive. We performed a meta-analysis to derive a more precise estimation of the relationship. A total of 18 studies including 5,175 cases and 6,463 controls were involved in this meta-analysis. When all studies were pooled into the meta-analysis, no significantly elevated breast cancer risk was associated with all genetic models (for additive model: OR = 1.273, 95% CI = 0.947-1.711, P heterogeneity = 0.000; P = 0.110; for dominant model: OR = 1.080, 95% CI = 0.945-1.234, P heterogeneity = 0.001; P = 0.259; for recessive model: OR = 1.242, 95% CI = 0.941-1.641, P heterogeneity = 0.000; P = 0.126; for allele comparison model: OR = 1.096, 95% CI = 0.976-1.230, P heterogeneity = 0.000; P = 0.121). In the subgroup analysis by controls source, the same results were found in all genetic models. In summary, this meta-analysis suggests that the COMT Val158Met polymorphism is not a risk factor for breast cancer development. However, large sample and representative population-based studies with homogeneous breast cancer patients and well-matched controls are warranted to confirm this finding.


Assuntos
Povo Asiático/genética , Neoplasias da Mama/genética , Catecol O-Metiltransferase/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Feminino , Humanos , Razão de Chances , Fatores de Risco
16.
Tumour Biol ; 35(1): 351-6, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23979975

RESUMO

Published studies on the association between FAS 1377G>A polymorphism and breast cancer susceptibility were inconclusive. To derive a more precise assessment of the association, a meta-analysis of published studies was performed. PubMed, Embase, and Web of Science were searched for eligible studies on the association between FAS 1377G>A polymorphism and breast cancer susceptibility. Five studies with a total of 2,905 cases and 3,090 controls were included into the meta-analysis. Overall, FAS 1377G>A polymorphism was significantly associated with increased susceptibility to breast cancer (for AA versus GG: odds ratio (OR) = 1.39, 95% confidence interval (95% CI) 1.12-1.72, P = 0.003; for AA/GA versus GG: OR = 1.18, 95% CI 1.06-1.32, P = 0.004; for AA versus GG/GA: OR = 1.28, 95% CI 1.05-1.56, P = 0.015). Subgroup analysis by ethnicity found that FAS 1377G>A polymorphism was significantly associated with increased susceptibility to breast cancer in Asians (for AA versus GG: OR = 1.48, 95% CI 1.16-1.89, P = 0.001; for AA/GA versus GG: OR = 1.24, 95% CI 1.06-1.46, P = 0.008; for AA versus GG/GA: OR = 1.35, 95% CI 1.08-1.69, P = 0.008), but the association was not found in Caucasians. Therefore, the findings of the meta-analysis suggest that FAS 1377G>A polymorphism is significantly associated with increased susceptibility to breast cancer in Asians.


Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Receptor fas/genética , Alelos , Neoplasias da Mama/etnologia , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Razão de Chances , Viés de Publicação
17.
Anticancer Drugs ; 25(6): 683-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24710190

RESUMO

Studies have shown that tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively induces apoptosis in cancer cells. However, breast cancer cells are generally resistant to TRAIL. In the present study, we explored the effect of bufalin on TRAIL-induced breast cancer cell apoptosis. The results showed that bufalin enhanced TRAIL-induced apoptosis in MCF-7 and MDA-MB-231 breast cancer cells by activating the extrinsic apoptotic pathway. Bufalin also promoted the clustering of death receptor 4 (DR4) and DR5 in aggregated lipid rafts. The cholesterol-sequestering agent methyl-ß-cyclodextrin reversed the DR4 and DR5 clustering and reduced bufalin+TRAIL-induced apoptosis. Overall, these results indicate that bufalin enhanced TRAIL-induced apoptosis in breast cancer cells by the partial redistribution of DRs in lipid rafts.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Bufanolídeos/farmacologia , Microdomínios da Membrana/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Colesterol/metabolismo , Feminino , Humanos , beta-Ciclodextrinas/farmacologia
18.
Br J Nutr ; 111(12): 2123-34, 2014 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-24606984

RESUMO

The present study was conducted to test the hypothesis that low concentrations of coated ZnO, as a substitute for a high concentration of ZnO (2250 mg Zn/kg), could improve intestinal immunity function and regulate microbiota composition, thus alleviating the incidence of diarrhoea in weaned piglets. A total of eighty-four cross-bred piglets, weaned at an age of 28 (SEM 1) d, were allocated randomly, on the basis of average initial body weight (7·72 (SEM 0·65) kg), to seven treatment groups as follows: a 250 mg Zn (ZnO)/kg group (low Zn; LZ) and a 2250 mg Zn (ZnO)/kg group (high Zn; HZ) that were offered diets containing ZnO at 250 and 2250 mg Zn/kg, respectively; and five experimental groups in which coated ZnO was added at 250, 380, 570, 760 and 1140 mg Zn/kg basal diet, respectively. The trial lasted 2 weeks. The results indicated that, compared with LZ treatment, supplementation with coated ZnO at 380 or 570 mg Zn/kg reduced (P< 0·05) diarrhoea index, increased (P< 0·05) duodenal villus height and the ratio of villus height:crypt depth, up-regulated (P< 0·05) the gene expression of insulin-like growth factor 1, zonula occludens protein-1, occludin, IL-10 and transforming growth factor ß1, and elevated (P< 0·05) secretory IgA concentration in the jejunal mucosa. Microbiota richness and the Shannon diversity index were also decreased (P< 0·05). Furthermore, piglets in the group fed coated ZnO at 380 or 570 mg Zn/kg did not differ from those in the HZ-fed group in relation to the aforementioned parameters. Collectively, a low concentration of coated ZnO (380 or 570 mg Zn/kg) can alleviate the incidence of diarrhoea by promoting intestinal development, protecting the intestinal mucosal barrier from damage, stimulating the mucosal immune system and regulating the microbiota composition.


Assuntos
Diarreia/veterinária , Imunidade nas Mucosas , Fatores Imunológicos/uso terapêutico , Mucosa Intestinal/imunologia , Doenças dos Suínos/prevenção & controle , Óxido de Zinco/uso terapêutico , Animais , Cruzamentos Genéticos , Diarreia/imunologia , Diarreia/microbiologia , Diarreia/prevenção & controle , Duodeno/crescimento & desenvolvimento , Duodeno/imunologia , Duodeno/microbiologia , Duodeno/ultraestrutura , Ingestão de Energia , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/imunologia , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Regulação da Expressão Gênica no Desenvolvimento , Imunoglobulina A Secretora/análise , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/química , Fatores Imunológicos/metabolismo , Mucosa Intestinal/crescimento & desenvolvimento , Mucosa Intestinal/microbiologia , Mucosa Intestinal/ultraestrutura , Jejuno/crescimento & desenvolvimento , Jejuno/imunologia , Jejuno/microbiologia , Jejuno/ultraestrutura , Lactobacillus/crescimento & desenvolvimento , Lactobacillus/imunologia , Lactobacillus/isolamento & purificação , Microvilosidades/imunologia , Microvilosidades/metabolismo , Microvilosidades/microbiologia , Microvilosidades/ultraestrutura , Sus scrofa , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/metabolismo , Doenças dos Suínos/microbiologia , Comprimidos com Revestimento Entérico , Desmame , Aumento de Peso , Óxido de Zinco/administração & dosagem , Óxido de Zinco/química , Óxido de Zinco/metabolismo
19.
ACS Nano ; 18(4): 3520-3530, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38230635

RESUMO

Conventional carbon fiber felt-reinforced aerogel composites are often used as lightweight thermal protection systems (TPSs) for aerospace craft. However, due to their poor oxidation resistance, they have gradually failed to handle increasingly harsh thermal environments. In this work, a nanoscale composite coating interface of SiC-ZrC ceramic precursor is first constructed on the fiber surface. Subsequently, using the coated fiber felt as a three-dimensional skeleton and through polymerization-induced phase separation, an aerogel composite with excellent thermal protection in extreme thermal environments is prepared. Owing to the in situ ceramization of this nanoscale interface at ultrahigh temperatures, the back temperature of the 12 mm thick aerogel is only 147 °C after exposure to an oxyacetylene flame at 1950 °C for 70 s. Meanwhile, the central region of the aerogel recedes by only 7%. Not only does this work provide a way to enhance aerogels by constructing a self-ceramizable nanoscale interface it is also expected that the developed aerogel composite can be applied in the ultrahigh-temperature thermal protection of future aerospace craft.

20.
ACS Appl Mater Interfaces ; 16(24): 31636-31647, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38848140

RESUMO

Rigid thermal protection materials such as ultra-high-temperature ceramics are desirable for applications in aerospace vehicles, but few materials can currently satisfy the emerging high-temperature sealing requirements for dynamic gaps created by the mismatch of the thermal expansion of different protection layers. Here, we design and fabricate a flexible biomimetic anisotropic deformation composite by multilayer cocuring onto fiber fabrics. It displays superior anisotropic deformation, whose longitudinal expansion ratio is 48 times greater than the transverse expansion ratio at specific temperatures. Furthermore, the ordered carbon structure created by transition-metal-catalyzed graphitization and the C/Si synergistic effect resulting from the combination of biomimetic fiber fabrics and SR enable the in situ formation of a high-temperature-resistant SiC crystalline phase within the char layer, ultimately resulting in exceptional thermal protection properties. By constructing hollow structures in situ, the back temperature of the composite, which is only 4.33 mm thick, is stabilized at 140 °C under the condition of continuous butane flame ablation (1300 °C) for 420 s. Multilayer structure and flexible features can facilitate large-scale preparation and arbitrary cutting and bending, adapted to different thermal protection areas.

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