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1.
Proc Biol Sci ; 283(1837)2016 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-27559063

RESUMO

Identifying the amount of prey available is an important part of an animal's foraging behaviour. The risk-sensitive foraging theory predicts that an organism's foraging decisions with regard to food rewards depending upon its satiation level. However, the precise interaction between optimal risk-tolerance and satiation level remains unclear. In this study, we examined, firstly, whether cuttlefish, with one of the most highly evolved nervous system among the invertebrates, have number sense, and secondly, whether their valuation of food reward is satiation state dependent. When food such as live shrimps is present, without training, cuttlefish turn toward the prey and initiate seizure behaviour. Using this visual attack behaviour as a measure, cuttlefish showed a preference for a larger quantity when faced with two-alternative forced choice tasks (1 versus 2, 2 versus 3, 3 versus 4 and 4 versus 5). However, cuttlefish preferred the small quantity when the choice was between one live and two dead shrimps. More importantly, when the choice was between one large live shrimp and two small live shrimps (a prey size and quantity trade-off), the cuttlefish chose the large single shrimp when they felt hunger, but chose the two smaller prey when they were satiated. These results demonstrate that cuttlefish are capable of number discrimination and that their choice of prey number depends on the quality of the prey and on their appetite state. The findings also suggest that cuttlefish integrate both internal and external information when making a foraging decision and that the cost of obtaining food is inversely correlated with their satiation level, a phenomenon similar to the observation that metabolic state alters economic decision making under risk among humans.


Assuntos
Cognição , Decápodes/fisiologia , Comportamento Predatório , Animais , Decapodiformes
2.
J Formos Med Assoc ; 114(9): 820-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24090635

RESUMO

BACKGROUND/PURPOSE: Ultrasonography (US) cannot demonstrate all the etiologies of biliary tract dilatation in patients with jaundice. Thus, we evaluated the etiologic yield of endosonography (EUS) for suspected obstructive jaundice when no definite pathology was found on US. Additionally, we sought to identify the predictors of the most common etiologies. METHODS: We performed a retrospective review of 123 consecutive patients who had undergone EUS for suspected obstructive jaundice when no definite pathology was identified on US. RESULTS: The most common diagnoses included no pathological obstruction (n = 43), pancreatobiliary malignancy (n = 41), and choledocholithiasis (n = 28). Pancreatobiliary malignancy was associated with common bile duct (CBD) dilatation, and fever and elevated alanine aminotransferase were predictors of choledocholithiasis (p < 0.05). The accuracy of EUS was 95.9% (118/123) for overall cause of suspected obstructive jaundice, 100% (40/40) for no pathological finding, 100% (23/23) for ampullary cancer, 100% (13/13) for pancreatic cancer, 75% (3/4) for CBD cancer, and 92.9% (26/28) for choledocholithiasis, respectively. Besides the two patients with focal chronic pancreatitis misdiagnosed as with pancreatic cancer, EUS missed the lesions in one CBD cancer patient and two patients with choledocholithiasis. The overall accuracy of EUS in ascertaining pancreatobiliary malignancy and choledocholithiasis was comparable (97.6%, 40/41 vs. 92.9%, 26/28; p > 0.05). CONCLUSION: Marked CBD dilatation (≥12 mm) should remind us of the high risk of malignancy, and the presence of CBD dilatation and fever is suggestive of choledocholithiasis. Negative EUS findings cannot assure any pathological obstruction in patients with clinically suspected obstructive jaundice.


Assuntos
Coledocolitíase/complicações , Neoplasias do Ducto Colédoco/complicações , Ducto Colédoco/fisiopatologia , Endossonografia , Icterícia Obstrutiva/diagnóstico por imagem , Neoplasias Pancreáticas/complicações , Idoso , Dilatação Patológica , Feminino , Humanos , Modelos Logísticos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
3.
One Health ; 19: 100852, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39129789

RESUMO

Highly pathogenic avian influenza (HPAI) is an important zoonotic disease. The study aims to identify farmer behaviour types to inform the design of behaviour change programmes for mitigating the transmission of HPAI. Therefore, the study utilised multivariate statistical analysis for gaining a better understanding of the relationships among farmers' 30 biosecurity behaviours, the risk of HPAI infection, and distinct features of commercial broiler farmers, which is different from using simple and few binary biosecurity measures. Convenience sampling was used to collect data from 303 Taiwan's farmers among which 40 farmers (13.2%) self-reported having had a HPAI outbreak in the study year while 16 farmers (5.3%) self-reported having had a HPAI outbreak in the past two years. Using categorical principal components analysis and a two-stage cluster analysis, four farmer clusters were identified with distinct features: 1)'Reserved' (4.6%) tended to choose 'No idea' for answering specific questions about HPAI; 2)'Secure' (76.3%) had a higher biosecurity status than the other farms; 3) 'Jeopardised' (16.8%) had a lower biosecurity status than the other farms; 4) 'No-response' (2.3%) tended to skip specific questions about HPAI. The biosecurity status of the 'Reserved' and 'No-response' clusters was undetermined, placing these farms at risk of HPAI infection. Compared to the 'Secure' cluster, the 'Jeopardised' cluster exhibited higher odds of self-reported HPAI in the study year (OR: 2.61, 95% CI: 1.22-5.58) and in the past two years (OR: 4.28, 95% CI: 1.39-13.19). Additionally, the 'Jeopardised' cluster showed increased odds of HPAI recurrence (OR: 4.01, 95% CI: 1.41-11.43). Our study demonstrates that inadequate biosecurity practices can elevate the occurrence or recurrence of HPAI outbreaks. The findings underscore the importance of distinguishing between these clusters to accurately assess the risk of HPAI infection across farms. Furthermore, understanding farmers' behaviours can inform the development of strategies aimed at behaviour change among farmers.

4.
Front Vet Sci ; 10: 1070482, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36846249

RESUMO

Introduction: Traditionally, it is believed that people's behaviours align with their attitudes; however, during COVID-19 pandemic, an attitude-behaviour gap in relation to preventive measures has been observed in recent studies. As such, the mixed-methods research was used to examine the relationships between farmers' biosecurity attitudes and behaviours in Taiwan's chicken industry based on the cognitive consistency theory. Methods: Content analysis of face-to-face interviews with 15 commercial chicken farmers identified their biosecurity responses to infectious disease threats. Results: The results indicated the mismatch of farmers' attitudes and behaviours towards specific biosecurity measures, in that they act differently than they think. The findings of the qualitative research allowed the research team to conduct the subsequent quantitative, confirmatory assessment to investigate the mismatch of farmers' attitudes and behaviours in 303 commercial broiler farmers. Survey data were analyzed to discover the relationships between farmers' attitudes and behaviours in relation to 29 biosecurity measures. The results show a mixed picture. The percentage of the farmers who had the attitude-behaviour gap towards 29 biosecurity measures ranged from 13.9 to 58.7%. Additionally, at the 5% significant level, there is an association between farmers' attitudes and behaviours for 12 biosecurity measures. In contrast, a significant association does not exist for the other 17 biosecurity measures. Specifically, out of the 17 biosecurity measures, the disconnection of farmers' attitudes and behaviours was observed in three specific biosecurity measures such as using a carcass storage area. Discussion: Based on a fairly large sample of farmers in Taiwan, this study confirms the existence of an attitude-behaviour gap in context and applies social theories to provide an in-depth understanding of how infectious diseases are managed in the animal health context. As the results demonstrate the necessity of tailoring biosecurity strategies to address the gap, it is time to reconsider the current approach by understanding farmers' real attitudes and behaviours in relation to biosecurity for the success of animal disease prevention and control at the farm level.

5.
Front Vet Sci ; 9: 959934, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36046509

RESUMO

Commercial poultry is often farmed in high-density facilities, therefore, predisposing exposure to threats of infectious diseases. Studies suggest that it is likely that farmers have little motivation to practise on-farm biosecurity. In Taiwan, where high-density intensive poultry production is commonplace, unfortunately, several avian influenza outbreaks have occurred over the past decade despite the establishment of biosecurity procedures. To develop effective interventions, it is essential to understand the determinants of farmers' biosecurity mindset through systems thinking. In this qualitative study, we directly explored the opinions of Taiwan's chicken farmers, and a grounded theory analysis was performed. The study revealed that farmers allocate resources based on their justification for the optimisation of resource utilisation, and biosecurity is the most concerning challenge. Farmers focus on the economic aspects of their production systems, particularly when the implementation of biosecurity increases production costs, and there are multifaceted, complex barriers to implementing on-farm biosecurity. Although the participant farmers accepted to take major responsibility for disease management, paradoxically, some farmers blamed the practicality of government regulations and government employees' attitudes. Additionally, the farmers rejected the government's intentions to ask farmers to take major responsibility for the outbreaks of avian influenza while some of them intended to ignore the perceived risks. Government interventions that were considered not directly related to biosecurity also negatively influenced farmers' willingness to improve biosecurity. Using the interview results together with information in the scientific literature, we constructed a modified six-level social-ecological model to explain the complex influences of macro socio-economic conditions on farmers' biosecurity mindset. The novelty of this research lies in its wider relevance to Taiwan's chicken production industry in that it provides first-hand evidence-based knowledge to demonstrate a wide number of determinants of farmers' biosecurity mindset. This social-ecological model highlights the importance of systems thinking for the development of behavioural interventions and allows adaptation to the local context. The findings of this study have relevance to Taiwan's chicken production industry and potentially to similar systems in other countries in the wider region and should result in more effective animal health management at the farm level.

6.
Bioorg Med Chem ; 16(5): 2697-706, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-18063374

RESUMO

Two series of 4-benzylideneamino- and 4-phenyliminomethyl-benzenesulfonamide derivatives were designed and synthesized for the evaluation as selective cyclooxygenase-2 (COX-2) inhibitors in a cellular assay using human whole blood (HWB). Extensive structure-activity relationships (SAR) were studied within these series. Several compounds were found to be novel and selective COX-2 inhibitors. Among them, the most potent and selective was 4-(3-carboxy-4-hydroxy-benzylideneamino)benzenesulfonamide (20, LA2135), (IC(50)'s for COX-1: 85.13 microM; COX-2: 0.74 microM; SI: 114.5), being more active COX-2 selective than celecoxib.


Assuntos
Compostos de Benzilideno/síntese química , Compostos de Benzilideno/farmacologia , Inibidores de Ciclo-Oxigenase 2/síntese química , Inibidores de Ciclo-Oxigenase 2/farmacologia , Iminas/química , Sulfonamidas/síntese química , Sulfonamidas/farmacologia , Aminação , Compostos de Benzilideno/química , Plaquetas/efeitos dos fármacos , Plaquetas/enzimologia , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/química , Humanos , Metilação , Estrutura Molecular , Relação Estrutura-Atividade , Sulfonamidas/química , Benzenossulfonamidas
7.
Biomicrofluidics ; 10(3): 034102, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27226813

RESUMO

Here, we report the characterization of the transport of micro- and nanospheres in a simple two-dimensional square nanoscale plasmonic optical lattice. The optical potential was created by exciting plasmon resonance by way of illuminating an array of gold nanodiscs with a loosely focused Gaussian beam. This optical potential produced both in-lattice particle transport behavior, which was due to near-field optical gradient forces, and high-velocity (∼µm/s) out-of-lattice particle transport. As a comparison, the natural convection velocity field from a delocalized temperature profile produced by the photothermal heating of the nanoplasmonic array was computed in numerical simulations. This work elucidates the role of photothermal effects on micro- and nanoparticle transport in plasmonic optical lattices.

9.
Bioorg Med Chem Lett ; 16(17): 4440-3, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16814546

RESUMO

A series of phenylazobenzenesulfonamide derivatives were designed and synthesized for the evaluation as selective cyclooxygenase-2 (COX-2) inhibitors in a cellular assay using human whole blood (HWB) and an enzymatic assay using purified ovine enzymes. Extensive structure-activity relationships (SAR) were studied within this series, and several of selective COX-2 inhibitors have been identified. Among them, compound 8, 4-(4-amino-2-methylsulfanyl-phenylazo)benzenesulfonamide, showed a potent inhibitory activity to the cyclooxygenase enzymes (IC(50)'s for COX-1: 23.28 microM; COX-2: 2.04 microM), being active but less COX-2 selective than celecoxib.


Assuntos
Compostos Azo/síntese química , Compostos Azo/farmacologia , Células Sanguíneas/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase 2/síntese química , Inibidores de Ciclo-Oxigenase 2/farmacologia , Sulfonamidas/síntese química , Sulfonamidas/farmacologia , Compostos Azo/química , Células Sanguíneas/enzimologia , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/química , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Sulfonamidas/química
10.
Bioorg Med Chem Lett ; 12(7): 1013-5, 2002 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-11909706

RESUMO

A new series of trans-stilbene benzenesulfonamide derivatives were designed and synthesized as potential antitumor agents. These new compounds were evaluated in the National Cancer Institute's 60 human tumor cell line in vitro screen. Compounds 9-13 were cytotoxic against several cell lines. Notably, two compounds, 9 and 12, demonstrated selective cytotoxic activity against BT-549 breast cancer (GI(50)=0.205 microM) and HT-29 colon cancer (GI(50)=0.554 microM), respectively.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/toxicidade , Benzeno/química , Neoplasias/tratamento farmacológico , Estilbenos/química , Sulfonamidas/síntese química , Sulfonamidas/toxicidade , Células Tumorais Cultivadas/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Relação Estrutura-Atividade
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