Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
1.
Sci Rep ; 7(1): 14291, 2017 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-29085050

RESUMO

Ebola virus disease (EVD) is a contagious, severe and often lethal form of hemorrhagic fever in humans. The association of EVD outbreaks with forest clearance has been suggested previously but many aspects remained uncharacterized. We used remote sensing techniques to investigate the association between deforestation in time and space, with EVD outbreaks in Central and West Africa. Favorability modeling, centered on 27 EVD outbreak sites and 280 comparable control sites, revealed that outbreaks located along the limits of the rainforest biome were significantly associated with forest losses within the previous 2 years. This association was strongest for closed forests (>83%), both intact and disturbed, of a range of tree heights (5->19 m). Our results suggest that the increased probability of an EVD outbreak occurring in a site is linked to recent deforestation events, and that preventing the loss of forests could reduce the likelihood of future outbreaks.


Assuntos
Conservação dos Recursos Naturais/estatística & dados numéricos , Surtos de Doenças/estatística & dados numéricos , Doença pelo Vírus Ebola/epidemiologia , Tecnologia de Sensoriamento Remoto , África Central/epidemiologia , África Ocidental/epidemiologia , Surtos de Doenças/prevenção & controle , Ebolavirus/isolamento & purificação , Doença pelo Vírus Ebola/prevenção & controle , Doença pelo Vírus Ebola/virologia , Atividades Humanas , Humanos , Floresta Úmida , Análise Espaço-Temporal , Árvores/fisiologia
2.
Nurs Times ; 111(10): 16-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26285437

RESUMO

Diabetes and dementia may manifest simultaneously: one is potentially life threatening, the other causes severe, progressive loss of memory and cognitive function. Where they coexist, they present nurses with challenges such as administering life-saving interventions to patients who are unable to give informed consent. This article offers guidance on the clinical and ethical challenges involved in blood glucose monitoring and medicines administration in patients with dementia.


Assuntos
Demência/complicações , Diabetes Mellitus Tipo 2/terapia , Demência/enfermagem , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/enfermagem , Humanos
4.
Bioorg Med Chem Lett ; 22(1): 71-5, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22172695

RESUMO

The design of a new clinical candidate histamine-H(3) receptor antagonist for the potential treatment of excessive daytime sleepiness (EDS) is described. Phenethyl-R-2-methylpyrrolidine containing biphenylsulfonamide compounds were modified by replacement of the sulfonamide linkage with a sulfone. One compound from this series, 2j (APD916) increased wakefulness in rodents as measured by polysomnography with a duration of effect consistent with its pharmacokinetic properties. The identification of a suitable salt form of 2j allowed it to be selected for further development.


Assuntos
Compostos de Bifenilo/química , Compostos de Bifenilo/farmacologia , Antagonistas dos Receptores Histamínicos/química , Pirrolidinas/química , Pirrolidinas/farmacologia , Receptores Histamínicos H3/química , Sulfonas/química , Animais , Área Sob a Curva , Encéfalo/metabolismo , Sistema Nervoso Central/efeitos dos fármacos , Química Farmacêutica/métodos , Desenho de Fármacos , Canal de Potássio ERG1 , Canais de Potássio Éter-A-Go-Go/química , Antagonistas dos Receptores Histamínicos/farmacocinética , Humanos , Concentração Inibidora 50 , Camundongos , Modelos Químicos , Pirrolidinas/antagonistas & inibidores , Ratos , Sono/efeitos dos fármacos , Temperatura , Vigília/efeitos dos fármacos
5.
J Med Chem ; 52(18): 5603-11, 2009 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-19722526

RESUMO

Antagonism of the histamine-H(3) receptor is one tactic being explored to increase wakefulness for the treatment of disorders such as excessive daytime sleepiness (EDS) as well as other sleep or cognitive disorders. Phenethyl-R-2-methylpyrrolidine containing biphenylsulfonamide compounds were shown to be potent and selective antagonists of the H(3) receptor. Several of these compounds demonstrated in vivo activity in a rat model of (R)-alpha-methyl histamine (RAMH) induced dipsogenia, and one compound (4e) provided an increase in wakefulness in rats as measured by polysomnographic methods. However, more detailed analysis of the PK/PD relationship suggested the presence of a common active metabolite which may preclude this series of compounds from further development.


Assuntos
Compostos de Bifenilo/química , Desenho de Fármacos , Agonismo Inverso de Drogas , Antagonistas dos Receptores Histamínicos/química , Antagonistas dos Receptores Histamínicos/farmacologia , Receptores Histamínicos H3/metabolismo , Sulfonamidas/química , Sulfonamidas/farmacologia , Administração Oral , Animais , Antagonistas dos Receptores Histamínicos/administração & dosagem , Antagonistas dos Receptores Histamínicos/farmacocinética , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Sulfonamidas/administração & dosagem , Sulfonamidas/farmacocinética , Sede/efeitos dos fármacos , Vigília/efeitos dos fármacos
7.
J Med Chem ; 51(2): 305-13, 2008 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-18095642

RESUMO

The synthesis and SAR of a novel 3-benzazepine series of 5-HT2C agonists is described. Compound 7d (lorcaserin, APD356) was identified as one of the more potent and selective compounds in vitro (pEC50 values in functional assays measuring [(3)H]phosphoinositol turnover: 5-HT2C = 8.1; 5-HT2A = 6.8; 5-HT2B = 6.1) and was potent in an acute in vivo rat food intake model upon oral administration (ED50 at 6 h = 18 mg/kg). Lorcaserin was further characterized in a single-dose pharmacokinetic study in rat (t1/2 = 3.7 h; F = 86%) and a 28-day model of weight gain in growing Sprague-Dawley rat (8.5% decrease in weight gain observed at 36 mg/kg b.i.d.). Lorcaserin was selected for further evaluation in clinical trials for the treatment of obesity.


Assuntos
Fármacos Antiobesidade/síntese química , Benzazepinas/síntese química , Obesidade/tratamento farmacológico , Agonistas do Receptor 5-HT2 de Serotonina , Animais , Fármacos Antiobesidade/farmacocinética , Fármacos Antiobesidade/farmacologia , Benzazepinas/farmacocinética , Benzazepinas/farmacologia , Linhagem Celular , Ingestão de Alimentos/efeitos dos fármacos , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Estereoisomerismo , Relação Estrutura-Atividade , Aumento de Peso/efeitos dos fármacos
8.
J AOAC Int ; 90(4): 1036-41, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17760341

RESUMO

The number of elevator facilities with laboratories to test shelled corn for aflatoxin on site is increasing. The inherent difficulty in accurately determining the true aflatoxin concentration of a lot of corn may have serious implications. Deviations from the true value are of even greater significance at busy locations where a high throughput is desired. This study was instituted to measure (1) the differences in aflatoxin test results between elevator laboratories and the Louisiana Agricultural Chemistry (LAC) laboratory and (2) the variability in aflatoxin test results associated with sampling, sample preparation, and analysis of shelled corn at such locations. One hundred lots of shelled corn from 10 elevators in Louisiana were analyzed for aflatoxin using the Aflatest method (at elevators and at the LAC laboratory) and high-performance column liquid chromatography (HPLC; LAC laboratory only). Mean aflatoxin levels determined at elevator laboratories were significantly (P < 0.05) lower from those obtained in the LAC laboratory using the Aflatest method. Overall, Aflatest method results were lower than those obtained by HPLC. This difference may be attributed to analyst technical dexterity, difficulty in providing careful attention to detail in a high throughput environment, and/or substandard facilities found at elevators. The total variance was partitioned into the combined sampling plus subsampling variance and analytical variance. The sampling and sample preparation steps accounted for about 91.5% of the total variability. When using the HPLC analytical method, the analytical step contributed only 8.5% to the total variance.


Assuntos
Aflatoxinas/análise , Técnicas de Química Analítica/métodos , Zea mays/química , Agricultura/métodos , Algoritmos , Cromatografia Líquida de Alta Pressão , Análise de Alimentos , Contaminação de Alimentos , Louisiana , Controle de Qualidade , Reprodutibilidade dos Testes , Projetos de Pesquisa
9.
Environ Health Perspect ; 114(12): 1898-903, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17185282

RESUMO

Consecutive outbreaks of acute aflatoxicosis in Kenya in 2004 and 2005 caused > 150 deaths. In response, the Centers for Disease Control and Prevention and the World Health Organization convened a workgroup of international experts and health officials in Geneva, Switzerland, in July 2005. After discussions concerning what is known about aflatoxins, the workgroup identified gaps in current knowledge about acute and chronic human health effects of aflatoxins, surveillance and food monitoring, analytic methods, and the efficacy of intervention strategies. The workgroup also identified public health strategies that could be integrated with current agricultural approaches to resolve gaps in current knowledge and ultimately reduce morbidity and mortality associated with the consumption of aflatoxin-contaminated food in the developing world. Four issues that warrant immediate attention were identified: a) quantify the human health impacts and the burden of disease due to aflatoxin exposure; b) compile an inventory, evaluate the efficacy, and disseminate results of ongoing intervention strategies; c) develop and augment the disease surveillance, food monitoring, laboratory, and public health response capacity of affected regions; and d) develop a response protocol that can be used in the event of an outbreak of acute aflatoxicosis. This report expands on the workgroup's discussions concerning aflatoxin in developing countries and summarizes the findings.


Assuntos
Aflatoxinas/intoxicação , Países em Desenvolvimento , Saúde Pública/métodos , Contaminação de Alimentos/legislação & jurisprudência , Contaminação de Alimentos/prevenção & controle , Humanos , Vigilância da População , Saúde Pública/legislação & jurisprudência , Organização Mundial da Saúde
10.
J Food Prot ; 68(6): 1294-301, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15954723

RESUMO

Qualitative and quantitative comparisons were conducted of commercially available immunodiagnostic devices for the detection of three select agents with oral LD50 values > or = 0.1 mg/kg of body weight. Ricin (oral LD50 > 1 mg/kg), amanitin (oral LD50 approximately 0.1 mg/kg), and T-2 toxin (oral LD50 > 1 mg/kg) were spiked into beverages, produce, dairy, and baked goods and assayed using commercially available enzyme-linked immunosorbent assays (ELISAs) and lateral flow devices. In all cases, the commercial diagnostic kits successfully detected all three select agents at concentrations below what might be a health concern. The considerable difference between the limit of detection of the immunodiagnostic devices employed (typically < or = 0.020 microg/g) and the amount of the select agent necessary to pose a health threat in a single serving of food facilitated the design of protocols for the high throughput screening of food samples. These protocols entailed simple extraction methods followed by sample dilution. Lateral flow devices and sandwich ELISAs for the detection of ricin had no significant background problems due to the food matrices. Competitive ELISAs, which typically have unacceptably high background reactions with food samples, successfully detected amanitin and T-2 toxin.


Assuntos
Amanitinas/isolamento & purificação , Ensaio de Imunoadsorção Enzimática/métodos , Contaminação de Alimentos/análise , Ricina/isolamento & purificação , Toxina T-2/isolamento & purificação , Amanitinas/imunologia , Reações Cruzadas , Relação Dose-Resposta Imunológica , Análise de Alimentos , Kit de Reagentes para Diagnóstico , Ricina/imunologia , Sensibilidade e Especificidade , Toxina T-2/imunologia
11.
J AOAC Int ; 88(1): 156-60, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15759737

RESUMO

Performance Tested Method multiple laboratory validations for the detection of peanut protein in 4 different food matrixes were conducted under the auspices of the AOAC Research Institute. In this blind study, 3 commercially available ELISA test kits were validated: Neogen Veratox for Peanut, R-Biopharm RIDASCREEN FAST Peanut, and Tepnel BioKits for Peanut Assay. The food matrixes used were breakfast cereal, cookies, ice cream, and milk chocolate spiked at 0 and 5 ppm peanut. Analyses of the samples were conducted by laboratories representing industry and international and U.S governmental agencies. All 3 commercial test kits successfully identified spiked and peanut-free samples. The validation study required 60 analyses on test samples at the target level 5 microg peanut/g food and 60 analyses at a peanut-free level, which was designed to ensure that the lower 95% confidence limit for the sensitivity and specificity would not be <90%. The probability that a test sample contains an allergen given a prevalence rate of 5% and a positive test result using a single test kit analysis with 95% sensitivity and 95% specificity, which was demonstrated for these test kits, would be 50%. When 2 test kits are run simultaneously on all samples, the probability becomes 95%. It is therefore recommended that all field samples be analyzed with at least 2 of the validated kits.


Assuntos
Técnicas de Química Analítica/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Análise de Alimentos/métodos , Hipersensibilidade a Amendoim , Alérgenos/análise , Arachis , Cacau , Grão Comestível , Estudos de Avaliação como Assunto , Sorvetes , Laboratórios , Reprodutibilidade dos Testes , Projetos de Pesquisa , Sensibilidade e Especificidade
12.
Bioorg Med Chem Lett ; 15(5): 1467-70, 2005 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15713408

RESUMO

We report on the synthesis, biological evaluation and structure-activity relationships for a series of 3-benzazepine derivatives as 5-HT(2C) receptor agonists. The compounds were evaluated in functional assays measuring [3H] phosphoinositol turnover in HEK-293 cells transiently transfected with h5-HT(2C), h5-HT(2A) or h5-HT(2B) receptors. Several compounds are shown to be potent and selective 5-HT(2C) receptor agonists, which decrease food intake in a rat feeding model.


Assuntos
Benzazepinas , Obesidade/tratamento farmacológico , Agonistas do Receptor 5-HT2 de Serotonina , Animais , Benzazepinas/síntese química , Benzazepinas/farmacologia , Benzazepinas/uso terapêutico , Linhagem Celular , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Ingestão de Alimentos/efeitos dos fármacos , Humanos , Masculino , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
13.
Adv Exp Med Biol ; 504: 173-9, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11922084

RESUMO

Naturally occurring toxicant contamination of foods with mycotoxins is unavoidable and unpredictable and poses a unique challenge to food safety. Aflatoxins are toxic mold metabolites produced by toxigenic strains of Aspergillus species. Primary commodities susceptible to aflatoxin contamination include corn, peanuts and cottonseed and animal-derived foods such as milk when the animal is fed aflatoxin-contaminated feed. Risks associated with aflatoxin-contaminated foods can be reduced through the use of specific processing and decontamination procedures. Factors, which influence the effectiveness of a specific process or procedure, include the chemical stability of the mycotoxin(s), nature of the process, type and interaction with the food/feed matrix and interaction with multiple mycotoxins if present. Practical decontamination procedures must: 1) inactivate, destroy, or remove the toxin, 2) not produce or leave toxic residues in the food/feed, 3) retain the nutritive value of the food/feed, 4) not alter the acceptability or the technological properties of the product, and, if possible, 5) destroy fungal spores. For aflatoxins, multiple processing and/or decontamination schemes have been successful in reducing aflatoxin concentrations to acceptable levels. Physical cleaning and separation procedures, where the mold-damaged kernel/seed/nut is removed from the intact commodity, can result in 40-80% reduction in aflatoxins levels. Processes such as dry and wet milling result in the distribution of aflatoxin residues into less utilized fractions of the commodity. The ammoniation of aflatoxin-contaminated commodities has altered the concentrations as well as toxic and carcinogenic effects of aflatoxin by greater than 99%. Nonbiological materials such as selected anticaking agents covalently bind aflatoxins from aqueous suspensions, diminish aflatoxin uptake by animals, prevent acute aflatoxicosis, and decrease aflatoxin residues in milk. Ultimately, the best processing or decontamination process is one that is approved by regulatory agencies, cost-effective, and reduces the mycotoxin concentration to acceptable levels.


Assuntos
Aflatoxinas/química , Manipulação de Alimentos , Aflatoxinas/antagonistas & inibidores , Aflatoxinas/isolamento & purificação , Amônia/química , Amônia/farmacologia , Animais , Descontaminação , Contaminação de Alimentos/prevenção & controle , Microbiologia de Alimentos , Humanos
14.
Adv Exp Med Biol ; 504: 277-85, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11922095

RESUMO

Control programs set up by the Food and Drug Administration (FDA) for aflatoxin, an unavoidable natural contaminant produced by specific molds that invade a number of feedstuffs and basic foods, provide an example of forces that affect risk assessment and management strategies by a regulatory agency. More recently, on an international scale, efforts to establish international food standards for fumonisin, deoxynivalenol, ochratoxin A, zearalenone, and patulin, as well as for aflatoxin, demonstrate the complexity of developing regulations and/or standards designed to protect consumer health and ensure fair trade practices on a global scale. Current FDA regulations for aflatoxins address public health concerns for potential contamination in basic foods, residues in milk, and animal feeds for numerous commodities and applications. Regulatory limits, sampling and analytical procedures, decontamination and/or diversion to less risk uses for contaminated product are components of mycotoxin control programs. Current efforts by FDA to establish regulatory controls for deoxynivalenol, fumonisin, and patulin add further insight on the role that safety and risk assessment procedures play in the development of action levels and advisories for mycotoxins.


Assuntos
Contaminação de Alimentos/legislação & jurisprudência , Micotoxinas/efeitos adversos , Micotoxinas/análise , Medição de Risco , Estados Unidos
15.
J Food Prot ; 57(2): 150-153, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31113139

RESUMO

Aerobic plate counts (APC), Listeria spp., and Vibrio spp. and antibiotic resistance patterns of Vibrio spp. were determined for imported shrimp from China, Ecuador, and Mexico obtained from wholesale/frozen and retail/previously frozen markets. Statistically significant differences in APC were observed among source countries and wholesale/frozen versus retail/previously frozen samples. Wholesale/frozen shrimp products were consistently excellent quality with respect to APC; higher contamination levels were observed in retail/previously frozen samples. Listeria spp. and L. monocytogenes were isolated from 16.7 and 6.7% of shrimp samples, respectively. Vibrio spp. were present in 63.3% of the samples, more often isolated from shrimp from Mexico or China than Ecuador. The majority of isolates were identified as V. parahaemolyticus (36.7%), V. alginolyticus (26.7%), or V. vulniftcus (16.7%), and 53.7% were resistant to at least one antibiotic. These data reveal that important differences in microbial quality occur in raw shrimp products as a function of source and between retail and Wholesale products.

16.
J Food Prot ; 54(12): 960-965, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31071832

RESUMO

The efficacy of the buffered sodium hypochlorite solution, Bionox, in controlling bacterial contamination was evaluated on fresh-cut poultry (chicken, light and dark meat), fish fillets, fruit, and vegetables. Food products were immersed in a nutrient broth suspension of Salmonella enteritidis (ATCC #13067) for 30 s and allowed to drip/air dry for 10 s prior to exposure to the sanitizing agent. Food products were then each vigorously washed with 100 ml of buffered peptone which was plated in serial dilution on XLD-N agar and incubated at 37°C for 24 h. Typical Salmonella colonies as well as non- Salmonella colonies growing on the XLD-N plates were counted and identified. Results showed the sanitizing solution to be effective in reducing S. enteritidis on all test foodstuffs. Count reductions of 4, 3, and 2 logs per gram on chicken, vegetables, and fruit, respectively, were achieved. Salmonella reductions of two logs were also achieved on fish fillets, but the sanitizer performance depended to some extent on the background bacterial flora present prior to the addition of the Salmonella test organism. The effect of the sanitizing solution on protein functionality, lipid oxidation, and starch degradation was determined using protein dispersibility and solubility assays, peroxide and iodine values, and changes in reducing sugars levels, respectively. Results showed no adverse effects on these parameters after exposure of the food products to the sanitizing solution.

17.
J Food Prot ; 53(9): 777-778, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31018314

RESUMO

Milks obtained from cows fed rations containing aflatoxin-contaminated cottonseed, ammonia-treated aflatoxin-contaminated cottonseed, and uncontaminated cottonseed were tested for mutagenic potential using the Salmonella /mammalian microsome mutagenicity assay using Salmonella typhimurium strains TA98 and TA100. Standard assay protocol was used with S-9 liver homogenate added. Samples including whole milk, nonfat dry milk powder, cream, and reconstituted whole milk were applied directly to the plates in triplicate. As a control, samples of whole milk, reconstituted whole milk, and nonfat dry milk powder from cows fed uncontaminated feed were spiked with aflatoxin B1 and tested for mutagenic activity. High levels of mutagenic activity were observed in all samples from cows exposed to aflatoxin-contaminated cottonseed and the aflatoxin-spiked milks. This high activity was not evident in whole milk and whole milk component samples from cows fed the ammonia-treated aflatoxin-contaminated cottonseed or nonaflatoxin containing cottonseed. A low level of mutagenic potential was evident in whole milk from the ammonia treated group using TA100 tester strain.

18.
J Food Prot ; 44(12): 921-922, 1981 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30856736

RESUMO

Milk from 34 dairy herds was tested over a 12-month period using a mastitis evaluation program in which Streptococcus agalactiae , Staphylococcus aureus and leucocytes were counted. There was a significant decrease in the total mastitic bacterial count ( S. agalactiae plus S. aureus ) over the testing period; however, the curve was bimodal, showing high points in the winter and summer months. The leucocyte count alone was not a good indicator of the mastitic condition of the herd. In approximately 12% of the test results, there was a high bacterial count with a low leucocyte count or a high leucocyte count with a low bacterial count.

19.
J Food Prot ; 40(2): 90-93, 1977 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30731527

RESUMO

14C-Labeled penicillic acid was produced by stationary culture incubation of Penicillium cyclopium (NRRL 1888) on a modified Raulin-Thom broth medium containing 14C-labeled acetate. Approximately 1.2 g of radioactive compound, with a specific activity of 23.0 µCi/mmole, was produced in 9 days in 1500 ml of the broth. Incorporation of the isotope into penicillic acid was 11. 9%. Production of the radiolabeled compound with high specific activity was achieved by correlating the monitoring of expired 14C-CO2 with production of penicillic acid during the fermentation. The effects of various growth substrates, pH, and incubation times on production of non-labeled penicillic acid also were investigated. Results show that sterile rice is an excellent substrate, that among liquid media examined, higher yields were obtained in stationary rather than in shake cultures, and that higher yields of penicillic acid were obtained at pH 3.5 or lower. Simultaneous monitoring of penicillic acid production and 14C-label incorporation is essential to detect and isolate a high yield of labeled compound with high specific activity.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA