Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 93
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Optom Vis Sci ; 101(5): 252-262, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38857038

RESUMO

PURPOSE: We aimed to develop a paradigm that can efficiently characterize motion percepts in people with low vision and compare their responses with well-known misperceptions made by people with typical vision when targets are hard to see. METHODS: We recruited a small cohort of individuals with reduced acuity and contrast sensitivity (n = 5) as well as a comparison cohort with typical vision (n = 5) to complete a psychophysical study. Study participants were asked to judge the motion direction of a tilted rhombus that was either high or low contrast. In a series of trials, the rhombus oscillated vertically, horizontally, or diagonally. Participants indicated the perceived motion direction using a number wheel with 12 possible directions, and statistical tests were used to examine response biases. RESULTS: All participants with typical vision showed systematic misperceptions well predicted by a Bayesian inference model. Specifically, their perception of vertical or horizontal motion was biased toward directions orthogonal to the long axis of the rhombus. They had larger biases for hard-to-see (low contrast) stimuli. Two participants with low vision had a similar bias, but with no difference between high- and low-contrast stimuli. The other participants with low vision were unbiased in their percepts or biased in the opposite direction. CONCLUSIONS: Our results suggest that some people with low vision may misperceive motion in a systematic way similar to people with typical vision. However, we observed large individual differences. Future work will aim to uncover reasons for such differences and identify aspects of vision that predict susceptibility.


Assuntos
Sensibilidades de Contraste , Percepção de Movimento , Baixa Visão , Humanos , Percepção de Movimento/fisiologia , Masculino , Feminino , Adulto , Baixa Visão/fisiopatologia , Sensibilidades de Contraste/fisiologia , Acuidade Visual/fisiologia , Pessoa de Meia-Idade , Psicofísica , Adulto Jovem , Teorema de Bayes , Estimulação Luminosa/métodos
2.
J Vis ; 22(12): 7, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36326743

RESUMO

To obtain a single percept of the world, the visual system must combine inputs from the two eyes. Understanding the principles that govern this binocular combination process has important real-world clinical and technological applications. However, most research examining binocular combination has relied on relatively simple visual stimuli and it is unclear how well the findings apply to real-world scenarios. For example, it is well-known that, when the two eyes view sine wave gratings with differing contrast (dichoptic stimuli), the binocular percept often matches the higher contrast grating. Does this winner-take-all property of binocular contrast combination apply to more naturalistic imagery, which include broadband structure and spatially varying contrast? To better understand binocular combination during naturalistic viewing, we conducted psychophysical experiments characterizing binocular contrast perception for a range of visual stimuli. In two experiments, we measured the binocular contrast perception of dichoptic sine wave gratings and naturalistic stimuli, and asked how the contrast of the surrounding context affected percepts. Binocular contrast percepts were close to winner-take-all across many of the stimuli when the surrounding context was the average contrast of the two eyes. However, we found that changing the surrounding context modulated the binocular percept of some patterns and not others. We show evidence that this contextual effect may be due to the spatial orientation structure of the stimuli. These findings provide a step toward understanding binocular combination in the natural world and highlight the importance of considering the effect of the spatial interactions in complex stimuli.


Assuntos
Sensibilidades de Contraste , Visão Binocular , Humanos , Olho
3.
Crit Rev Food Sci Nutr ; 61(5): 756-776, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32255367

RESUMO

Citrus, one of the most popular fruits worldwide, contains various functional components, including flavonoids, dietary fibers (DFs), essential oils (EOs), synephrines, limonoids, and carotenoids. The functional components of citrus attract special attention due to their health-promoting effects. Food components undergo complex biotransformation by host itself and the gut microbiota after oral intake, which alters their bioaccessibility, bioavailability, and bioactivity in the host body. To better understand the health effects of citrus fruits, it is important to understand the in-vivo biotransformation of citrus functional components. We reviewed the biotransformation of citrus functional components (flavonoids, DFs, EOs, synephrines, limonoids, and carotenoids) in the body from their intake to excretion. In addition, we described the importance of biotransformation in terms of health effects. This review would facilitate mechanistic understanding of the health-promoting effect of citrus and its functional components, and also provide guidance for the development of health-promoting foods based on citrus and its functional components.


Assuntos
Citrus , Biotransformação , Carotenoides , Flavonoides , Frutas
5.
Mar Drugs ; 17(11)2019 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-31744059

RESUMO

Nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease closely associated with metabolic syndrome, but there are no validated pharmacological therapies. The aim of this study was to investigate the effect of chitosan oligosaccharide (COS) on NAFLD. Mice were fed either a control diet or a high-fat diet (HFD) with or without COS (200 or 400 mg/kg body weight (BW)) by oral gavage for seven weeks. Administration with COS significantly lowered serum lipid levels in the HFD-fed mice. The hepatic lipid accumulation was significantly decreased by COS, which was attributed to decreased expressions of lipogenic genes and increased expressions of fatty ß-oxidation-related genes. Moreover, pro-inflammatory cytokines, neutrophils infiltration, and macrophage polarization were decreased by COS in the liver. Furthermore, COS ameliorated hepatic oxidative stress by activating the nuclear factor E2-related factor 2 (Nrf2) pathway and upregulating gene expressions of antioxidant enzymes. These beneficial effects were mediated by the activation of the adenosine monophosphate-activated protein kinase (AMPK) signaling pathway. Therefore, COS might be a potent dietary supplement to ameliorate NAFLD.


Assuntos
Quitosana/farmacologia , Dieta Hiperlipídica/efeitos adversos , Inflamação/tratamento farmacológico , Metabolismo dos Lipídeos/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Oligossacarídeos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Citocinas/metabolismo , Inflamação/metabolismo , Lipídeos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo
6.
J Sci Food Agric ; 99(3): 1366-1374, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30094852

RESUMO

BACKGROUND: This study evaluated the effects of dietary zinc oxide nanoparticles (nano-ZnOs) on growth performance, zinc status, intestinal morphology, microflora population, and immune response in weaned piglets. A total of 150 weaned piglets (9.37 ± 0.48 kg) were randomly allotted to five dietary treatments and fed with a basal diet (control), or the basal diet supplemented with nano-ZnOs at 150, 300, or 450 mg kg-1 , and 3000 mg kg-1 ZnO for 21 days. After a feeding test, six pigs from the control, 450 mg kg-1 nano-ZnOs and 3000 mg kg-1 ZnO groups were slaughtered. RESULTS: Compared with the control, dietary supplements of nano-ZnOs and ZnO could improve (P < 0.05) average daily weight gain (ADG), average daily feed intake (ADFI), and villus height to crypt depth ratio in the duodenum and jejunum, and decrease (P < 0.05) diarrhea incidence. Zinc retention in the serum, heart, liver, spleen and kidney of pigs supplemented with nano-ZnOs and ZnO was increased (P < 0.05). Nano-ZnOs decreased (P < 0.05) the zinc excretion compared with conventional ZnO. Lower Escherichia coli counts in the cecum, colon, and rectum were observed (P < 0.05) in the nano-ZnOs group compared with the other groups. Compared with the control, ZnO and nano-ZnOs increased (P < 0.05) the serum concentration of IgA, IL-6, and TNF-α, and decreased (P < 0.05) the concentration of IgM. CONCLUSION: These results indicated that low doses of nano-ZnOs can have beneficial effects on growth performance, intestinal morphology and microflora, and immunity in weanling pigs, which are similar to the effects of pharmacological dosages of conventional ZnO. Nano-ZnOs may reduce mineral excretion, which may reduce environmental challenges. © 2018 Society of Chemical Industry.


Assuntos
Microbioma Gastrointestinal , Intestinos/crescimento & desenvolvimento , Nanopartículas/metabolismo , Suínos/imunologia , Óxido de Zinco/metabolismo , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Suplementos Nutricionais/análise , Feminino , Intestinos/anatomia & histologia , Intestinos/imunologia , Intestinos/microbiologia , Masculino , Nanopartículas/microbiologia , Suínos/crescimento & desenvolvimento , Suínos/metabolismo , Suínos/microbiologia , Desmame
7.
Cell Physiol Biochem ; 46(5): 1779-1792, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29705796

RESUMO

BACKGROUND/AIMS: The intestinal mucosa forms a physical and metabolic barrier against the diffusion of pathogens, toxins, and allergens from the lumen into the circulatory system. Early weaning, a critical phase in swine production, can compromise intestinal barrier function through mucosal damage and alteration of tight junction integrity Maintenance of intestinal barrier function plays a pivotal role in optimum gastrointestinal health. In this study, we investigated the effects of Clostridium tyrobutyricum (C.t) on intestinal barrier dysfunction induced by lipopolysaccharide (LPS) and the underlying mechanisms involved in intestinal barrier protection. METHODS: A Transwell model of IPEC-J2 cells was used to imitate the intestinal barrier. Fluorescence microscopy and flow cytometry were used to evaluate apoptosis. Real-time PCR was used to detect apoptosis-related genes and the downstream genes of the p38/c-Jun N-terminal kinase (JNK) signaling pathways. Western blotting was used to measure the expressions of tight junction proteins and mitogen-activated protein kinases. RESULTS: C.t efficiently maintained trans-epithelium electrical resistance values and intestinal permeability after LPS-induced intestinal barrier disruption. The expressions of tight junction proteins (ZO-1, claudin-1, and occludin) were promoted when IPEC-J2 cells were treated with C.t. Fluorescence imaging and flow cytometry revealed that C.t qualitatively and quantitatively inhibited LPS-induced cell apoptosis. C.t also increased the relative expression of the anti-apoptotic gene Bcl-2 and decreased that of the apoptotic genes Bax and caspase-3/-8. Moreover, the protective effect of C.t on damaged intestinal cell models was associated with suppression of p38 and JNK phosphorylation, negative regulation of the relative expressions of downstream genes including AP-1, ATF-2, ELK-1, and p53, and activation of Stat3 expression. CONCLUSIONS: These findings indicate that C.t may promote intestinal integrity, suggesting a novel probiotic effect on intestinal barrier function.


Assuntos
Apoptose , Clostridium tyrobutyricum/metabolismo , Mucosa Intestinal/citologia , Mucosa Intestinal/microbiologia , Lipopolissacarídeos/metabolismo , Sistema de Sinalização das MAP Quinases , Probióticos/metabolismo , Animais , Linhagem Celular , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Permeabilidade , Suínos
8.
J Clin Lab Anal ; 32(2)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28493522

RESUMO

BACKGROUND: This survey was initiated to estimate the current status of turnaround time (TAT) monitoring of clinical biochemistry in China, provide baseline data for establishment of quality specifications and analyze the impact factors of TAT. METHODS: 738 laboratories were included. Questionnaires involved general information and data of related indicators of TAT during 1 week were provided to participating laboratories. Nine quality indicators were covered, which were medians, 90th and outlier rates of pre-examination, examination, and post-examination TAT. The 25th percentile, median, and 75th percentile of TATs were calculated as optimum, desirable, and minimum quality specifications. Percentages and sigma values were used to describe the outlier rates. Mann-Whitney and Kruskal-Wallis tests were used to identify the potential impacts of TAT. RESULTS: Response rate of this survey was 46.44%. More than 50% of the laboratories indicated they had set up target TATs in three time intervals and monitored TATs generally. The post-examination TAT of most laboratories was 0min, while the pre-examination and examination TAT varied. Sigma values of outlier rates for 45%~60% of laboratories were above 4, while 15%~20% of labs whose sigma values were below 3. Group comparisons suggested nurse or mechanical pipeline transportation, link laboratory information system with hospital information system, and using computer reporting instead of printing report were related to shorter TATs. CONCLUSIONS: Despite of the remarkable progresses of TATs in China, there was also room to improve. Laboratories should strengthen the construction of information systems, identify reasons for TAT delay to improve the service quality continuously.


Assuntos
Testes de Química Clínica/estatística & dados numéricos , Testes de Química Clínica/normas , Laboratórios/estatística & dados numéricos , Ensaio de Proficiência Laboratorial/estatística & dados numéricos , China , Humanos , Inquéritos e Questionários , Fatores de Tempo
9.
Carcinogenesis ; 38(4): 455-464, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28207072

RESUMO

Different cancer chemopreventive agents may act synergistically and their combination may produce enhanced protective effects against carcinogenesis than each individual agent alone. Herein, we investigated the chemopreventive effects of nobiletin (NBT, a citrus polymethoxyflavone) and atorvastatin (ATST, a lipid-lowering drug) in colon cancer cells/macrophages and an azoxymethane (AOM)-induced colon carcinogenesis rat model. The results demonstrated that co-treatments of NBT/ATST produced enhanced growth inhibitory and anti-inflammatory effects on the colon cancer cells and macrophages, respectively. Isobologram analysis confirmed that these interactions between NBT and ATST were synergistic. NBT/ATST co-treatment also synergistically induced extensive cell cycle arrest and apoptosis in colon cancer cells. Oral administration of NBT (0.1%, w/w in diet) or ATST (0.04%, w/w in diet) significantly decreased colonic tumor incidence and multiplicity in AOM-treated rats. Most importantly, co-treatment of NBT/ATST at their half doses (0.05% NBT + 0.02% ATST, w/w in diet) resulted in even stronger inhibitory effects on colonic tumor incidence and multiplicity than did NBT or ATST alone at higher doses. Statistical analysis confirmed that the enhanced chemopreventive activities against colon carcinogenesis in rats by the NBT/ATST combination were highly synergistic. Our results further demonstrated that NBT/ATST co-treatment profoundly modulated key cellular signaling regulators associated with inflammation, cell proliferation, cell cycle progression, apoptosis, angiogenesis and metastasis in the colon of AOM-treated rats. In conclusion, for the first time, our results demonstrated a strong synergy in inhibiting colon carcinogenesis produced by the co-treatment of NBT and ATST, which provided a scientific basis for using NBT in combination with ATST for colon cancer chemoprevention in humans.


Assuntos
Anticarcinógenos/farmacologia , Atorvastatina/farmacologia , Carcinogênese/efeitos dos fármacos , Colo/efeitos dos fármacos , Neoplasias do Colo/prevenção & controle , Flavonas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Azoximetano/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quimioprevenção/métodos , Colo/patologia , Neoplasias do Colo/patologia , Sinergismo Farmacológico , Quimioterapia Combinada/métodos , Células HT29 , Humanos , Masculino , Camundongos , Ratos , Ratos Endogâmicos F344
10.
Am J Public Health ; 107(3): 433-440, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28103075

RESUMO

OBJECTIVES: To evaluate the effectiveness of a community-based liver cancer prevention program on hepatitis B virus (HBV) screening among low-income, underserved Vietnamese Americans at high risk. METHODS: We conducted a cluster randomized trial involving 36 Vietnamese community-based organizations and 2337 participants in Pennsylvania, New Jersey, and New York City between 2009 and 2014. We randomly assigned 18 community-based organizations to a community-based multilevel HBV screening intervention (n = 1131). We randomly assigned the remaining 18 community-based organizations to a general cancer education program (n = 1206), which included information about HBV-related liver cancer prevention. We assessed HBV screening rates at 6-month follow-up. RESULTS: Intervention participants were significantly more likely to have undergone HBV screening (88.1%) than were control group participants (4.6%). In a Cochran-Mantel-Haenszel analysis, the intervention effect on screening outcomes remained statistically significant after adjustment for demographic and health care access variables, including income, having health insurance, having a regular health provider, and English proficiency. CONCLUSIONS: A community-based, culturally appropriate, multilevel HBV screening intervention effectively increases screening rates in a high-risk, hard-to-reach Vietnamese American population.


Assuntos
Hepatite B/etnologia , Neoplasias Hepáticas/etnologia , Neoplasias Hepáticas/prevenção & controle , Neoplasias Hepáticas/virologia , Programas de Rastreamento , Adulto , Asiático , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , New Jersey/epidemiologia , Cidade de Nova Iorque/epidemiologia , Educação de Pacientes como Assunto , Pennsylvania/epidemiologia , Prevalência , Vietnã/etnologia
11.
Nutrients ; 16(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38398817

RESUMO

Obesity and its complications constitute a main threat to global human health. The purpose of this investigation was to explore the influences of Clostridium tyrobutyricum (Ct) on lipid metabolism, intestinal barrier function, and intestinal microbiome in obese mice induced by a high-fat diet (HFD). After establishing the obesity model, 107 CFU/mL and 108 CFU/mL C. tyrobutyricum were used to intervene in HFD-fed mice by gavage for six weeks, and indexes related to obesity were measured. In the liver of HFD-fed mice, the results revealed that C. tyrobutyricum reduced liver weight and the levels of triglyceride (TG), total cholesterol (TC), and nonesterified fatty acid (NEFA), along with decreasing red lipid droplets and fat vacuoles. After C. tyrobutyricum intervention, the mRNA expression of peroxisome proliferator-activated receptor-γ (PPARγ) was downregulated, and AMP-activated protein kinase (AMPK), peroxisome proliferator-activated receptor-α (PPARα), adipose triglyceride lipase (ATGL), and hormone-sensitive lipase (HSL) were upregulated in the liver. Additionally, C. tyrobutyricum alleviated intestinal morphology injury caused by HFD, decreased the expression of tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), and IL-1ß in the colon, and upregulated tight junction protein expression. In addition, 16S rRNA sequencing revealed that C. tyrobutyricum increases the diversity of intestinal microbiota. Overall, C. tyrobutyricum improved HFD-induced lipid metabolism disorders, preserved the intestinal barrier's integrity, and modulated the structure of the intestinal microbiome. These findings provide a novel insight into the role of C. tyrobutyricum as a probiotic in regulating lipid metabolism.


Assuntos
Clostridium tyrobutyricum , Microbioma Gastrointestinal , Humanos , Animais , Camundongos , Dieta Hiperlipídica/efeitos adversos , Metabolismo dos Lipídeos , Microbioma Gastrointestinal/fisiologia , Camundongos Obesos , Função da Barreira Intestinal , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Fígado/metabolismo , Obesidade/metabolismo , Camundongos Endogâmicos C57BL
12.
Bioact Mater ; 38: 207-224, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38756201

RESUMO

Healing of fractures or bone defects is significantly hindered by overactivated osteoclasts and inhibited osteogenesis in patients with abnormal bone metabolism. Current clinical approaches using titanium alloys or stainless steel provide mechanical support but have no biological effects on bone regeneration. Therefore, designing and fabricating degradable metal materials with sufficient mechanical strength and bidirectional regulation of both osteoblasts and osteoclasts is a substantial challenge. Here, this study first reported an adaptive biodegradable Zn-0.8 Mg alloy with bidirectional regulation of bone homeostasis, which promotes osteogenic differentiation by activating the Pi3k/Akt pathway and inhibits osteoclast differentiation by inhibiting the GRB2/ERK pathway. The anti-osteolytic ability of the Zn-0.8 Mg alloy was verified in a mouse calvarial osteolysis model and its suitability for internal fracture fixation with high-strength screws was confirmed in the rabbit femoral condyle fracture model. Furthermore, in an aged postmenopausal rat femoral condyle defect model, 3D printed Zn-0.8 Mg scaffolds promoted excellent bone regeneration through adaptive structures with good mechanical properties and bidirectionally regulated bone metabolism, enabling personalized bone defect repair. These findings demonstrate the substantial potential of the Zn-0.8 Mg alloy for treating fractures or bone defects in patients with aberrant bone metabolism.

13.
Front Bioeng Biotechnol ; 11: 1117954, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36777251

RESUMO

Porous tantalum implants are a class of materials commonly used in clinical practice to repair bone defects. However, the cumbersome and problematic preparation procedure have limited their widespread application. Additive manufacturing has revolutionized the design and process of orthopedic implants, but the pore architecture feature of porous tantalum scaffolds prepared from additive materials for optimal osseointegration are unclear, particularly the influence of porosity. We prepared trabecular bone-mimicking tantalum scaffolds with three different porosities (60%, 70% and 80%) using the laser powder bed fusing technique to examine and compare the effects of adhesion, proliferation and osteogenic differentiation capacity of rat mesenchymal stem cells on the scaffolds in vitro. The in vivo bone ingrowth and osseointegration effects of each scaffold were analyzed in a rat femoral bone defect model. Three porous tantalum scaffolds were successfully prepared and characterized. In vitro studies showed that scaffolds with 70% and 80% porosity had a better ability to osteogenic proliferation and differentiation than scaffolds with 60% porosity. In vivo studies further confirmed that tantalum scaffolds with the 70% and 80% porosity had a better ability for bone ingrowh than the scaffold with 60% porosity. As for osseointegration, more bone was bound to the material in the scaffold with 70% porosity, suggesting that the 3D printed trabecular tantalum scaffold with 70% porosity could be the optimal choice for subsequent implant design, which we will further confirm in a large animal preclinical model for better clinical use.

14.
Innovation (Camb) ; 4(6): 100503, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37732016

RESUMO

Bacterial infectious diseases are one of the leading causes of death worldwide. Even with the use of multiple antibiotic treatment strategies, 4.95 million people died from drug-resistant bacterial infections in 2019. By 2050, the number of deaths will reach 10 million annually. The increasing mortality may be partly due to bacterial heterogeneity in the infection microenvironment, such as drug-resistant bacteria, biofilms, persister cells, intracellular bacteria, and small colony variants. In addition, the complexity of the immune microenvironment at different stages of infection makes biomaterials with direct antimicrobial activity unsatisfactory for the long-term treatment of chronic bacterial infections. The increasing mortality may be partly attributed to the biomaterials failing to modulate the active antimicrobial action of immune cells. Therefore, there is an urgent need for effective alternatives to treat bacterial infections. Accordingly, the development of immunomodulatory antimicrobial biomaterials has recently received considerable interest; however, a comprehensive review of their research progress is lacking. In this review, we focus mainly on the research progress and future perspectives of immunomodulatory antimicrobial biomaterials used at different stages of infection. First, we describe the characteristics of the immune microenvironment in the acute and chronic phases of bacterial infections. Then, we highlight the immunomodulatory strategies for antimicrobial biomaterials at different stages of infection and their corresponding advantages and disadvantages. Moreover, we discuss biomaterial-mediated bacterial vaccines' potential applications and challenges for activating innate and adaptive immune memory. This review will serve as a reference for future studies to develop next-generation immunomodulatory biomaterials and accelerate their translation into clinical practice.

15.
Front Psychol ; 13: 1005313, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36211900

RESUMO

It could be claimed that without any doubt the Internet has revolutionized the educational system to a great extent. Even though some are still interested in traditional ways of teaching and learning and also face-to-face classes, technological advances, in particular, social media have changed the English as a foreign language (EFL) contexts in a way that they will not be compatible with any other methods that have long been utilized before. Despite the fact that some studies have been conducted in different learning contexts, to the researcher's best knowledge, attention has not been focused on the importance of social media inside and outside the classroom on EFL students' indulgence. Therefore, the aim of this review is to synthesize the findings of the previous studies to highlight the role of social media in EFL students' engagement throughout class and outside the class in both face-to-face and online classes. To reach this goal, this review first discusses the impact of social media on engagement, and then engagement and its classifications are dealt with. Next, the relationship between using social media and students' engagement is discussed. And finally, some implications are proposed.

16.
Anim Biosci ; 35(8): 1109-1120, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35073660

RESUMO

Antibiotics used to be supplemented to animal feeds as growth promoter and as an effective strategy to reduce the burden of pathogenic bacteria present in the gastro-intestinal tract. However, in-feed antibiotics also kill bacteria that may be beneficial to the animal. Secondly, unrestricted use of antibiotics enhanced the antibiotic resistance in pathogenic bacteria. To overcome above problems, scientists are taking a great deal of measures to develop alternatives of antibiotics. There is convincing evidence that probiotics could replace in-feed antibiotics in poultry production. Because they have beneficial effects on growth performance, meat quality, bone health and eggshell quality in poultry. Better immune responses, healthier intestinal microflora and morphology which help the birds to resist against disease attack were also identified with the supplementation of probiotics. Probiotics establish cross-feeding between different bacterial strains of gut ecosystem and reduce the blood cholesterol level via bile salt hydrolase activity. The action mode of probiotics was also updated according to recently published literatures, i.e antimicrobial substances generation or toxin reduction. This comprehensive review of probiotics is aimed to highlight the beneficial effects of probiotics as a potential alternative strategy to replace the antibiotics in poultry.

17.
Front Psychol ; 13: 1002562, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36186361

RESUMO

Learners' willingness to communicate in a foreign language is regarded as a critical issue in educational contexts, so the role of emotional factors in learners' willingness to communicate has drawn the attention of investigators. This review investigated the studies on the relationship between English as a Foreign Language (EFL) learners' grit, foreign language anxiety, and willingness to communicate. This review showed a significant relationship between learners' grit and willingness to communicate. The earlier studies showed that gritty learners with incessant inspiring efforts are more likely to communicate in a foreign language. This review also indicated that lower anxious learners tend to have more willingness to communicate. Earlier studies also indicated that the theories, such as broaden-and-build, positive psychology, dynamic system, affective filter, and attentional control can justify the relationships between these constructs. Moreover, the study has some pedagogical implications and suggestions for teachers, learners, syllabus designers, material developers, teacher educators, policy-makers, and advisors. The ideas can improve their awareness of teachers' willingness to communicate, grit, and foreign language anxiety in educational environments.

18.
Animals (Basel) ; 12(9)2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35565553

RESUMO

Experiment was designed to analyze the effect of low caloric diets, supplemented with ß-mannanase on growth performance, carcass characteristics, nutrient digestibility, and other parameters in broilers. In this study, 400 broiler chicks were randomly divided into four treatments (Cont: without ß-mannanase; LM-30, MM-60, and HM-90: supplemented with 200, 400, and 600 mg/kg ß-mannanase, respectively). Dietary metabolizable energy (ME) in Cont was standard (starter diet 3100 kcal/kg; finisher diet 3200 kcal/kg) and reduced by 30, 60, and 90 kcal/kg, correspondingly in ß-mannanase-supplemented treatments. The results exhibited that growth performance was not affected by reducing dietary energy levels with supplementation of ß-mannanase. Ileal digestibility of DM and CF was improved (p < 0.01) by supplementation of ß-mannanase at low dietary ME levels. Concerning carcass traits, the relative weight of breast meat, drumstick, and abdominal fat increased (p < 0.05) with ß-mannanase supplementation in low-ME diets. Treatment HM-90 showed significantly (p < 0.05) better results regarding villus height and VH:CD. It could be concluded from the present results that supplementation of ß-mannanase could improve the nutrient digestibility so that it is possible to reduce the dietary energy level without compromising production performance, carcass trails, and meat quality in broilers.

19.
Antioxidants (Basel) ; 11(7)2022 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-35883875

RESUMO

This study was conducted to investigate the protective effect of chitosan oligosaccharide (COS) against lipopolysaccharide (LPS)-induced intestinal injury. The results demonstrated that COS improved the mucosal morphology of the jejunum and colon in LPS-challenged mice. COS alleviated the LPS-induced down-regulation of tight junction protein expressions and reduction of goblet cells number and mucin expression. The mRNA expressions of anti-microbial peptides secreted by the intestinal cells were also up-regulated by COS. Additionally, COS decreased pro-inflammatory cytokine production and neutrophil recruitment in the jejunum and colon of LPS-treated mice. COS ameliorated intestinal oxidative stress through up-regulating the mRNA expressions of nuclear factor E2-related factor 2 and downstream antioxidant enzymes genes. Correlation analysis indicated that the beneficial effects of COS on intestinal barrier function were associated with its anti-inflammatory activities and antioxidant capacity. Our study provides evidence for the application of COS to the prevention of intestinal barrier dysfunction caused by the stress of a LPS challenge.

20.
Front Nutr ; 9: 912591, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35634412

RESUMO

Although resveratrol (RES) is barely detectable in the plasma and tissues upon oral consumption, collective evidence reveals that RES presents various bioactivities in vivo, including anti-inflammation and anti-cancer. This paradox necessitates further research on profiling and characterizing the biotransformation of RES, as its metabolites may contribute profound biological effects. After 4-week oral administration, 11 metabolites of RES were identified and quantified in mice by HPLC-MS/MS, including dihydro-resveratrol (DHR), lunularin (LUN), and conjugates (sulfates and glucuronides) of RES, DHR and LUN. Importantly, DHR, LUN, and their conjugates were much more abundantly distributed in tissues, gastrointestinal tract (GIT), and biological fluids compared to RES and its conjugates. Moreover, we established that DHR and LUN were gut bacteria-derived metabolites of RES, as indicated by their depletion in antibiotic-treated mice. Furthermore, the biological activities of RES, DHR, and LUN were determined at physiologically relevant levels. DHR and LUN exhibited stronger anti-inflammatory and anti-cancer effects than RES at the concentrations found in mouse tissues. In summary, our study profiled the tissue distribution of the metabolites of RES after its oral administration in mice and uncovered the important role of gut microbial metabolites of RES in the biological activities of RES in vivo.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa