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1.
J Contam Hydrol ; 248: 104007, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35405439

RESUMO

Long-term estimates of natural source zone depletion (NSZD) rates for petroleum LNAPL (light non-aqueous phase liquid) sites are not available. One-off measurements are often thought valid over the lifetime of LNAPL sites. In the context of site-wide LNAPL mass estimates, we report site-specific gasoline and diesel NSZD rates spanning 21-26 years. Using depth profiles of soil gases (oxygen, carbon dioxide, methane, volatiles) above LNAPL, NSZD rates were estimated in 1994, 2006 and 2020 for diesel and 1999, 2009 and 2020 for gasoline. Each date also had soil-core mass estimates, which together with NSZD rates allow estimation of the longevity for LNAPL presence. Site-wide coring (in 1992, 2002, 2007) estimated LNAPL mass reductions of 12,000 t. For diesel NSZD, the ratio of NSZD rates for 2006 (16,000-49,000 L/ha/y) to those in 2020 (2600-14,000 L/ha/y) was ~3-6. By 2020, the 1994 diesel NSZD rates would have predicted the entire removal of measured mass (16-42 kg/m2). For gasoline, NSZD rates in 1999 were extremely high (50,000-270,000 L/ha/y) but 9-27 times lower (5800-10,000 L/ha/y) a decade later. The gasoline NSZD rates in 1999 predicted near complete mass removal in 2-12 years, but 10-11 kg/m2 was measured 10 and 21 years later which is 26% of the initial mass in 1999. The outcomes substantiate the need to understand NSZD rate changes over the lifetime of LNAPL-impacted sites.


Assuntos
Petróleo , Poluentes do Solo , Biodegradação Ambiental , Dióxido de Carbono/análise , Gasolina , Solo , Poluentes do Solo/análise
2.
Br Poult Sci ; 61(3): 328-335, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31899948

RESUMO

1. The aim of this study was to investigate the effects of a combined probiotic product (Lactobacillus paracasei, L. plantarum, and L. rhamnosus) on egg quality, sulphur compounds in manure and serum biochemistry of second cycle hens. 2. A total of 48 White Leghorn hens, at 52- to 54 weeks of age, were treated in a completely randomised design with water containing 0 or 1.8375 × 1010 cfu/l of probiotics for 8 weeks. 3. Probiotic supplementation did not affect egg quality. Albumen height and Haugh units were in general lowest in week 2 and highest in week 6. 4. For manure and serum parameters, water with or without probiotics produced statistically similar effects. An interacting trend for increasing concentrations of methyl mercaptan in manure was noted for probiotics x week, and should be further investigated. The week of supplementation significantly affected hydrogen sulphide, dimethyl sulphide, and triglycerides.


Assuntos
Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Água Potável , Lactobacillus , Ração Animal/análise , Animais , Galinhas , Dieta , Suplementos Nutricionais , Ovos , Feminino , Esterco , Óvulo , Compostos de Enxofre
3.
Res Vet Sci ; 122: 64-71, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30463030

RESUMO

Studies show that in poultry houses, hydrogen sulfide (H2S) is present in a much higher concentration than its odor threshold of 10 ppb for humans and has a short-lived deleterious effect on White Leghorns at concentrations of 0.2% H2S. A possible way to reduce H2S emissions (often exhausted into the environment) is to decrease its concentration in manure by adding high fiber byproducts and probiotics in diets. A combination of probiotics (Lactobaccillus paracasei, Lactobaccillus plantarum, and Lactobaccillus rhamnosus at 1.56 mL per 10 L (to provide 3.64 × 106 cfu/L of each species) in chlorinated drinking water and sunflower seed meal (SFM) were evaluated for their early effects on the H2S concentration in manure and specific measurements in serum. Sixty-four White Leghorn inbred crosses (65- to 74-week-old) were randomly allocated into two replicates of four treatments including a Control, Control + Probiotics, Control + Probiotics + 20% SFM, and Control + 20% SFM. After a 7-day acclimation period with different treatments, fecal matter was analyzed for total sulfur (TS), sulfate-sulfur (SO4-S), and H2S while blood serum was analyzed for amylase, calcium, phosphate, cholesterol, and triglycerides. Results indicated that probiotics significantly increased SO4-S, whereas 20% SFM decreased H2S, total sulfur, and increased sulfate sulfur. Dietary supplementation of SFM also significantly decreased serum amylase activity, calcium, and phosphorus.


Assuntos
Ração Animal/análise , Galinhas , Helianthus , Sulfeto de Hidrogênio/química , Lactobacillus , Esterco/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Fibras na Dieta , Probióticos , Distribuição Aleatória , Soro/química
4.
Rev Chil Pediatr ; 89(1): 59-66, 2018 Feb.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29664504

RESUMO

Children and adolescents with rheumatologic diseases require specialized and comprehensive care, but pediatric rheumatologists and immunologists are concentrated in hospitals with specific, high-cost and modern technology. Considering that some patients with juvenile idiopathic arthritis (JIA) live in rural, remote and limited accessibility areas, the use of Telemedicine (TM) can optimize diag nosis, follow-up and prognosis. OBJECTIVE: Reporting 10 years of experience of a mixed care model: face-to-face and distance, using basic TM; the institutional impact, advantages, disadvantages and acceptance informed by parents and patients. PATIENTS AND METHOD: Exploratory, descriptive, and re trospective study with qualitative component. After the authorization of a scientific-ethics committee of the Reloncaví Health Service and the application of informed consent, a review of medical records was carried out and a qualitative survey was applied to parents and children over 14 years of age with JIA, seen between 2005-2015 in the pediatric ambulatory rheumatology polyclinic of Puerto Montt Hospital. RESULTS: The were 27/35 participating patients with JIA attended by a trained pediatrician and assisted by distance (1,000 km) by an immunologist. The 8/35 patients did not answer by choice or change of address. The 70% of parents and patients accepted the model of care and 4% would pre fer sporadic care only by specialists for diagnosis and follow-up. The number of patients transferred annually decreased from 10 to 1. The advantages of the care model outweighed the disadvantages perceived by parents and JIA patients. CONCLUSION: The use of TM tools in JIA decreased transfers, improved follow-up and were considered advantageous by patients and their parents.


Assuntos
Artrite Juvenil/terapia , Acessibilidade aos Serviços de Saúde/organização & administração , Serviços de Saúde Rural/organização & administração , Telemedicina , Adolescente , Criança , Pré-Escolar , Chile , Feminino , Pesquisas sobre Atenção à Saúde , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Hospitais , Humanos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Pesquisa Qualitativa , Estudos Retrospectivos , Serviços de Saúde Rural/estatística & dados numéricos , Telemedicina/métodos , Telemedicina/organização & administração , Telemedicina/estatística & dados numéricos
5.
Rev. chil. pediatr ; 89(1): 59-66, feb. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-900069

RESUMO

Resumen: Niños y adolescentes con enfermedades reumatológicas, requieren atención especializada e integral, sin embargo, reumatólogos e inmunólogos pediátricos se concentran en hospitales con tecnología específica, costosa y moderna. Como algunos pacientes con Artritis idiopática juvenil (AIJ) vive en áreas rurales, lejanas y de accesibilidad limitada, el uso de Telemedicina (TM) puede optimizar el diagnóstico, seguimiento y pronóstico. Objetivo: Mostrar 10 años de experiencia de un modelo de atención mixta: presencial y a distancia, usando TM básica; el impacto institucional, ventajas, des ventajas y aceptación reportados por padres y pacientes. Pacientes y Método: Estudio exploratorio, descriptivo, retrospectivo con componente cualitativo. Previa autorización de comité ético-científico del Servicio de salud del Reloncaví y la aplicación de consentimiento/asentimiento informado, se efectuó revisión de historias clínicas y se aplicó encuesta cualitativa a padres y niños mayores de 14 años con AIJ, atendidos entre 2005-2015 en el policlínico de reumatología infantil Hospital Puerto Montt. Resultados: Participaron 27/35 pacientes con AIJ atendidos por pediatra capacitado, aseso rado a distancia (1.000 km) por inmunólogo. 8/35 pacientes no contestaron por opción o cambio de domicilio. 70 % de padres y pacientes aceptaron el modelo de atención y 4% preferirían atención esporádica solo por especialista para diagnóstico y seguimiento. El número de pacientes trasladados anualmente disminuyó de 10 a 1. Las ventajas del modelo de atención superaron las desventajas per cibidas por padres y pacientes con AIJ. Conclusión: El uso de herramientas de TM en AIJ disminuyó los traslados, mejoró el seguimiento y fue considerado ventajoso por los padres y pacientes.


Abstract: Children and adolescents with rheumatologic diseases require specialized and comprehensive care, but pediatric rheumatologists and immunologists are concentrated in hospitals with specific, high-cost and modern technology. Considering that some patients with juvenile idiopathic arthritis (JIA) live in rural, remote and limited accessibility areas, the use of Telemedicine (TM) can optimize diag nosis, follow-up and prognosis. Objective: Reporting 10 years of experience of a mixed care model: face-to-face and distance, using basic TM; the institutional impact, advantages, disadvantages and acceptance informed by parents and patients. Patients and Method: Exploratory, descriptive, and re trospective study with qualitative component. After the authorization of a scientific-ethics committee of the Reloncaví Health Service and the application of informed consent, a review of medical records was carried out and a qualitative survey was applied to parents and children over 14 years of age with JIA, seen between 2005-2015 in the pediatric ambulatory rheumatology polyclinic of Puerto Montt Hospital. Results: The were 27/35 participating patients with JIA attended by a trained pediatrician and assisted by distance (1,000 km) by an immunologist. The 8/35 patients did not answer by choice or change of address. The 70% of parents and patients accepted the model of care and 4% would pre fer sporadic care only by specialists for diagnosis and follow-up. The number of patients transferred annually decreased from 10 to 1. The advantages of the care model outweighed the disadvantages perceived by parents and JIA patients. Conclusion: The use of TM tools in JIA decreased transfers, improved follow-up and were considered advantageous by patients and their parents.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Artrite Juvenil/terapia , Telemedicina/métodos , Telemedicina/organização & administração , Telemedicina/estatística & dados numéricos , Serviços de Saúde Rural/organização & administração , Acessibilidade aos Serviços de Saúde/organização & administração , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Chile , Estudos Retrospectivos , Serviços de Saúde Rural/estatística & dados numéricos , Pesquisas sobre Atenção à Saúde , Pesquisa Qualitativa , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Hospitais
6.
Br Poult Sci ; 58(5): 536-543, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28547997

RESUMO

1. This study was conducted to evaluate the effects of purine nucleosides on performance, gut morphology, intestinal enzymes and immunity functions in broiler chickens from 0 to 21 d of age. 2. A total of 360 1-d-old male chickens (Cobb 500) were randomly assigned to 4 treatments with 6 replications. Experimental diets consisted of a control without any additives and diets containing 0.1% pure adenosine, 0.1% pure guanosine and 0.1% equal aliquots of pure adenosine and guanosine. Two birds per cage (12 birds per treatment) were killed on d 11 and 21 in order to obtain serum samples for lipid profile, jejunal samples for morphology and mucosal immunity, digestive enzymes for epithelial maturation, and bursa and spleen samples for relative weight of immune organs to live body weight. 3. Birds receiving adenosine in their diets showed a significant increase in body weight and average daily gain and a significantly lower feed conversion ratio compared to the control birds. Villus height and width in jejunal samples also increased significantly in birds supplemented with adenosine. Although maltase was not affected by the experimental diets, adenosine increased alkaline phosphatase and aminopeptidase. Adenosine and its combination with guanosine boosted mucosal immunity as a result of increased IgA production. While there was no significant difference among treatments regarding the relative weight of the spleen, adenosine increased the relative weight of the bursa of Fabricius. Present results also showed that adding guanosine to broiler diets had no significant effects on growth, gut morphology, enzymes activity and immunological indices. 4. In conclusion, the improvement in growth performance, gut morphology and immunity in birds receiving adenosine demonstrated that pure adenosine could be a beneficial feed additive for the poultry industry, while guanosine showed no significant improvement.


Assuntos
Galinhas/fisiologia , Imunidade nas Mucosas/efeitos dos fármacos , Intestinos/fisiologia , Nucleosídeos de Purina/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bolsa de Fabricius/fisiologia , Galinhas/anatomia & histologia , Galinhas/crescimento & desenvolvimento , Galinhas/imunologia , Dieta/veterinária , Suplementos Nutricionais/análise , Mucosa Intestinal/imunologia , Intestinos/enzimologia , Intestinos/crescimento & desenvolvimento , Masculino , Tamanho do Órgão , Nucleosídeos de Purina/administração & dosagem , Distribuição Aleatória , Baço/fisiologia
7.
BMJ Open ; 6(5): e010933, 2016 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-27165648

RESUMO

OBJECTIVES: The aim of this systematic review of randomised controlled trials (RCTs) and controlled trials (non-RCTs, NRCTs) is to investigate the effectiveness and related costs of case management (CM) for patients with heart failure (HF) predominantly based in the community in reducing unplanned readmissions and length of stay (LOS). SETTING: CM initiated either while as an inpatient, or on discharge from acute care hospitals, or in the community and then continuing on in the community. PARTICIPANTS: Adults with a diagnosis of HF and resident in Organisation for Economic Co-operation and Development countries. INTERVENTION: CM based on nurse coordinated multicomponent care which is applicable to the primary care-based health systems. PRIMARY AND SECONDARY OUTCOMES: Primary outcomes of interest were unplanned (re)admissions, LOS and any related cost data. Secondary outcomes were primary healthcare resources. RESULTS: 22 studies were included: 17 RCTs and 5 NRCTs. 17 studies described hospital-initiated CM (n=4794) and 5 described community-initiated CM of HF (n=3832). Hospital-initiated CM reduced readmissions (rate ratio 0.74 (95% CI 0.60 to 0.92), p=0.008) and LOS (mean difference -1.28 days (95% CI -2.04 to -0.52), p=0.001) in favour of CM compared with usual care. 9 trials described cost data of which 6 reported no difference between CM and usual care. There were 4 studies of community-initiated CM versus usual care (2 RCTs and 2 NRCTs) with only the 2 NRCTs showing a reduction in admissions. CONCLUSIONS: Hospital-initiated CM can be successful in reducing unplanned hospital readmissions for HF and length of hospital stay for people with HF. 9 trials described cost data; no clear difference emerged between CM and usual care. There was limited evidence for community-initiated CM which suggested it does not reduce admission.


Assuntos
Administração de Caso/organização & administração , Serviços de Saúde Comunitária/organização & administração , Prestação Integrada de Cuidados de Saúde/organização & administração , Insuficiência Cardíaca/terapia , Hospitalização/estatística & dados numéricos , Administração de Caso/economia , Ensaios Clínicos como Assunto , Serviços de Saúde Comunitária/economia , Custos de Cuidados de Saúde , Insuficiência Cardíaca/economia , Humanos
8.
Eur J Clin Nutr ; 69(2): 282-4, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24642782

RESUMO

Emerging evidence suggests taurolidine reduces the risk of repeated episodes of catheter related blood stream infections (CRBSI) in a subgroup of patients receiving home parenteral nutrition (HPN). We defined 3 indications where taurolidine could be considered and retrospectively analysed data from patients who were treated over a 10 year period to examine the validity of these criteria. Twenty-two patients were identified from a total HPN population of 81, representing 33.2 years of experience. The overall CRBSI rate pre- and post-taurolidine usage was reduced from 5.71 to 0.99 infections per 1000 patient parenteral nutrition days (P-value <0.0001), with reductions identified in each smaller subgroup, confirming previous reports of a significant reduction in infections when taurolidine is used as secondary prophylaxis and providing initial data suggesting the benefit of its use as primary prophylaxis.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Bacteriemia/prevenção & controle , Infecções Relacionadas a Cateter/prevenção & controle , Nutrição Parenteral no Domicílio/efeitos adversos , Seleção de Pacientes , Taurina/análogos & derivados , Tiadiazinas/uso terapêutico , Bacteriemia/epidemiologia , Bacteriemia/etiologia , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/etiologia , Protocolos Clínicos , Humanos , Incidência , Estudos Retrospectivos , Taurina/uso terapêutico
9.
Toxicol Rep ; 1: 373-378, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-28962253

RESUMO

The present study aimed to evaluate the effect of chronic co-exposure to chlorpyrifos (CPF) and deltamethrin (DLT) on erythrocyte osmotic fragility, lipid peroxidation and the ameliorative effect of alpha-lipoic acid (ALA) on erythrocyte fragility. Thirty-six male Wistar rats divided into six groups of six rats each were used for the study. Groups I (S/oil) and II (ALA) were given soya oil (2 ml/kg) and ALA (60 mg/kg), respectively. Rats in group III (DLT) and IV (CPF) were exposed to DLT (6.25 mg/kg) and CPF (4.75 mg/kg) (1/20th of the previously determined LD50 of 125 mg/kg and 95 mg/kg, respectively, over a period of 48 h). Rats in group V (CPF + DLT) were co-exposed to CPF (4.75 mg/kg) and DLT (6.25 mg/kg), while those in group VI (ALA + CPF + DLT) were pretreated with ALA (60 mg/kg) and then co-exposed to CPF and DLT, 45 min later. The treatments were administered by gavage once daily for a period of 16 weeks. Blood collected at the end of the experimental period were analyzed for erythrocyte osmotic fragility and malondialdehyde (MDA) concentration. The study showed that chronic co-exposure to CPF and DLT resulted in an increase in erythrocyte fragility and MDA concentration which were ameliorated by supplementation with alpha-lipoic acid. The study concluded that repeated co-exposure to CPF and DLT elevated erythrocyte fragility probably due to increased lipid peroxidation, and pretreatment with alpha-lipoic acid ameliorated these alterations.

10.
Phytother Res ; 27(7): 1006-11, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22911568

RESUMO

Herbal medicines, especially plant-derived extracts, have been used to treat Type 2 diabetes mellitus (T2DM) for many centuries, and offer the potential of cheap and readily available alternatives to conventional pharmaceuticals in developing countries. Extracts of Gymnema sylvestre (GS) have anti-diabetic activities and have been used as a folk medicine in India for centuries. We have investigated the effects of a novel high molecular weight GS extract termed OSA® on glucose tolerance in insulin-resistant ob/ob mice, and on insulin secretion and synthesis by isolated mouse islets. Single administration of OSA® (500 mg/kg) to ob/ob mice 30 min before an intraperitoneal glucose load improved their abnormal glucose tolerance. In vitro studies indicated that OSA® (0.25 mg/ml) initiated rapid and reversible increases in insulin secretion from isolated mouse islets at substimulatory (2 mM) and stimulatory (20 mM) glucose concentrations. In addition, prolonged treatment (24-48 h) of mouse islets with OSA® elevated the expression of preproinsulin mRNA and maintained the total insulin content of mouse islets in the presence of stimulated insulin secretion. These effects of OSA® are consistent with its potential use as a therapy for the hyperglycemia associated with obesity-related T2DM.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Intolerância à Glucose/tratamento farmacológico , Gymnema sylvestre/química , Hipoglicemiantes/uso terapêutico , Insulina/biossíntese , Ilhotas Pancreáticas/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Insulina/genética , Insulina/metabolismo , Resistência à Insulina , Ilhotas Pancreáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/metabolismo , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , RNA Mensageiro/metabolismo
11.
Hum Exp Toxicol ; 30(1): 19-24, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20378658

RESUMO

Chronic exposure to chlorpyrifos (CPF) has been shown to cause increased lipoperoxidative changes in the erythrocyte membranes. The relationship between chronic CPF-induced lipoperoxidative changes and erythrocyte fragility has not been elucidated. The aim of the present study is to evaluate the role of lipoperoxidation on CPF-induced erythrocyte fragility and the ameliorative effect of vitamin C. Twenty animals divided at random into four groups of five animals each served as subject for this study. Rats in group I served as the control group and were given only soya oil at a dose of 2 mL/kg body weight (b.w.). Rats in group II were dosed with vitamin C (100 mg/kg b.w.) and then supplemented with soya oil (2 mL/kg b.w.), while those in group III were administered with CPF only at a dose of 10.6 mg/kg b.w. (~one-eighth of the previously determined median lethal dose [LD(50)]). Rats in group IV were pretreated with 100 mg/kg b.w. of vitamin C, and then dosed with CPF at a dose of 10.6 mg/kg b.w., 30 min later. The different treatment regimens were orally administered daily for a period of 17 weeks. Blood collected from the animals at the end of the test period were analyzed for erythrocyte osmotic fragility and malonaldehyde (MDA) concentration as an index of lipid peroxidation. The study showed that CPF caused significant increase in erythrocyte fragility and MDA concentration, which were ameliorated by pretreatment with vitamin C. In conclusion, the study showed that CPF-evoked erythrocyte fragility due to increased lipoperoxidative changes was ameliorated by pretreatment with vitamin C.


Assuntos
Antioxidantes/uso terapêutico , Ácido Ascórbico/uso terapêutico , Clorpirifos/toxicidade , Eritrócitos/efeitos dos fármacos , Inseticidas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Animais , Inibidores da Colinesterase/toxicidade , Eritrócitos/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Fragilidade Osmótica , Distribuição Aleatória , Ratos , Ratos Wistar , Testes de Toxicidade Crônica
12.
Poult Sci ; 87(9): 1889-96, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18753459

RESUMO

If freshly dried tomato pomace could be fed to poultry, its naturally occurring alpha-tocopherol would retard lipid oxidation during further processing, long-term frozen storage, and heating of poultry meat; however, the high fiber content in this agricultural by-product adversely affects its use. Experiments were conducted to investigate the chemical composition and in vitro true digestibility of amended (without and with 487 micromol of manganese/g) tomato pomace substrate after treatment with the white-rot fungus Pleurotus ostreatus. In treated pomace without manganese, protein content was improved by 3.1%, cellulose and hemicellulose decreased over time, but lignin degradation was not detected. In addition, treated pomace without manganese showed a significant reduction of in vitro true digestibility. Manganese in pomace inhibited fungal growth and did not enhance lignin degradation. Under the conditions of the experiment, P. ostreatus improved the nutritional composition of tomato pomace; however, it did not reduce lignin. It is possible that manganese amendment at the level used affected gaseous conditions (O(2) consumption and CO(2) evolution rates), important factors that must be considered when attempting to enhance accelerated lignin degradation by P. ostreatus.


Assuntos
Ração Animal/análise , Manganês/química , Pleurotus/química , Solanum lycopersicum , Animais , Manipulação de Alimentos , Fatores de Tempo
13.
Neuroscience ; 154(1): 397-408, 2008 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-18281159

RESUMO

Auditory localization experiments typically either require subjects to judge the location of a sound source from a discrete set of response alternatives or involve measurements of the accuracy of orienting responses made toward the source location. To compare the results obtained by both methods, we trained ferrets by positive conditioning to stand on a platform at the center of a circular arena prior to stimulus presentation and then approach the source of a broadband noise burst delivered from 1 of 12 loudspeakers arranged at 30 degrees intervals in the horizontal plane. Animals were rewarded for making a correct choice. We also obtained a non-categorized measure of localization accuracy by recording head-orienting movements made during the first second following stimulus onset. The accuracy of the approach-to-target responses declined as the stimulus duration was reduced, particularly for lateral and posterior locations, although responses to sounds presented in the frontal region of space and directly behind the animal remained quite accurate. Head movements had a latency of approximately 200 ms and varied systematically in amplitude with stimulus direction. However, the final head bearing progressively undershot the target with increasing eccentricity and rarely exceeded 60 degrees to each side of the midline. In contrast to the approach-to-target responses, the accuracy of the head orienting responses did not change much with stimulus duration, suggesting that the improvement in percent correct scores with longer stimuli was due, at least in part, to re-sampling of the acoustical stimulus after the initial head turn had been made. Nevertheless, for incorrect trials, head orienting responses were more closely correlated with the direction approached by the animals than with the actual target direction, implying that at least part of the neural circuitry for translating sensory spatial signals into motor commands is shared by these two behaviors.


Assuntos
Vias Auditivas/fisiologia , Orientação , Localização de Som/fisiologia , Estimulação Acústica/métodos , Análise de Variância , Animais , Comportamento Animal , Furões , Movimentos da Cabeça , Psicofísica , Fatores de Tempo
14.
Antimicrob Agents Chemother ; 48(4): 1256-71, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15047528

RESUMO

Hyperexpression of the Saccharomyces cerevisiae multidrug ATP-binding cassette (ABC) transporter Pdr5p was driven by the pdr1-3 mutation in the Pdr1p transcriptional regulator in a strain (AD/PDR5(+)) with deletions of five other ABC-type multidrug efflux pumps. The strain had high-level fluconazole (FLC) resistance (MIC, 600 microg ml(-1)), and plasma membrane fractions showed oligomycin-sensitive ATPase activity up to fivefold higher than that shown by fractions from an isogenic PDR5-null mutant (FLC MIC, 0.94 microg ml(-1)). In vitro inhibition of the Pdr5p ATPase activity and chemosensitization of cells to FLC allowed the systematic screening of a 1.8-million-member designer D-octapeptide combinatorial library for surface-active Pdr5p antagonists with modest toxicity against yeast cells. Library deconvolution identified the 4-methoxy-2,3,6-trimethylbenzensulfonyl-substituted D-octapeptide KN20 as a potent Pdr5p ATPase inhibitor (concentration of drug causing 50% inhibition of enzyme activity [IC(50)], 4 microM) which chemosensitized AD/PDR5(+) to FLC, itraconazole, and ketoconazole. It also inhibited the ATPase activity of other ABC transporters, such as Candida albicans Cdr1p (IC(50), 30 microM) and Cdr2p (IC(50), 2 microM), and chemosensitized clinical isolates of pathogenic Candida species and S. cerevisiae strains that heterologously hyperexpressed either ABC-type multidrug efflux pumps, the C. albicans major facilitator superfamily-type drug transporter Ben(R)p, or the FLC drug target lanosterol 14 alpha-demethylase (Erg11p). Although KN20 also inhibited the S. cerevisiae plasma membrane proton pump Pma1p (IC(50), 1 microM), the peptide concentrations required for chemosensitization made yeast cells permeable to rhodamine 6G. KN20 therefore appears to indirectly chemosensitize cells to FLC by a nonlethal permeabilization of the fungal plasma membrane.


Assuntos
Antifúngicos/farmacologia , Fluconazol/farmacologia , Oligopeptídeos/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Adenosina Trifosfatases/antagonistas & inibidores , Candida/efeitos dos fármacos , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Avaliação Pré-Clínica de Medicamentos , Farmacorresistência Fúngica , Células Epiteliais/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Corantes Fluorescentes , Humanos , Testes de Sensibilidade Microbiana , Microscopia Confocal , Oligopeptídeos/toxicidade , Biblioteca de Peptídeos , Rodaminas/metabolismo , Sefarose
15.
Toxicol In Vitro ; 17(4): 471-80, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12849731

RESUMO

Where substances are intended for use in personal products applied to the skin an assessment of potential phototoxic hazard is required. This report describes a tiered testing strategy involving in vitro assays used for the phototoxic hazard assessment of a personal product ingredient (Ingredient X). The initial assay was measurement of a UV/visible absorption spectrum to identify absorption at relevant wavelengths. This was followed by in vitro assays for phototoxicity (3T3 cell neutral red uptake phototoxicity test) and photoallergy (photobinding to human serum albumin). These in vitro screens gave equivocal results for Ingredient X which appeared to suggest a weak phototoxic reaction. To further evaluate the phototoxic hazard of Ingredient X to human skin, a phototoxicity assay using a 3-D human skin model was conducted. Ingredient X did not cause phototoxicity in this assay. Overall conclusions from these studies were that although Ingredient X showed slight intrinsic potential for photoactivation, it was unlikely to present a hazard to human skin. This report illustrates the value in a step-wise strategy of the use of human skin models to help interpret the results of other in vitro phototoxicity assays.


Assuntos
Cosméticos/toxicidade , Dermatite Fototóxica/patologia , Testes de Toxicidade , Células 3T3 , Animais , Química Farmacêutica , Humanos , Camundongos , Modelos Biológicos , Transtornos de Fotossensibilidade/induzido quimicamente , Transtornos de Fotossensibilidade/patologia , Extratos Vegetais/toxicidade , Testes Cutâneos , Espectrofotometria Ultravioleta , Raios Ultravioleta
16.
Clin Microbiol Infect ; 8(2): 85-92, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11952721

RESUMO

OBJECTIVE: To study the emergence of macrolide resistance in throat flora following treatment with clarithromycin or azithromycin. METHODS: Throat samples were collected before and after treatment and plated as a lawn on Columbia blood agar with an erythromycin E test strip. Minimum inhibitory concentrations (MICs) of erythromycin, clarithromycin and azithromycin were determined against isolates of distinct morphology with erythromycin E test MIC results equal to or greater than 2 mg/L. Polymerase chain reaction techniques were used to determine the genetic mechanisms of resistance. RESULTS: There were 749 resistant isolates of which 474 (63%) were streptococci. Only a quarter of the patients had no resistant streptococci before treatment started. There were increases in the numbers of resistant isolates and in the number of patients carrying a resistant flora during and after treatment. The most common genes identified were mefA/E in isolates with low-level resistance and ermA/M in isolates with high-level resistance. CONCLUSIONS: There is a pool of streptococci carrying genes associated with macrolide resistance in the normal respiratory flora of generally healthy adults. Differences between the patients treated with clarithromycin and those treated with azithromycin were difficult to assess because of the large number of patients in each group with macrolide-resistant streptococci before treatment. Although there were some differences these were not statistically significant.


Assuntos
Azitromicina/uso terapêutico , Claritromicina/uso terapêutico , Farmacorresistência Bacteriana/genética , Eritromicina/análogos & derivados , Eritromicina/farmacologia , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/microbiologia , Streptococcus/efeitos dos fármacos , Antibacterianos/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Faringe/microbiologia , Reação em Cadeia da Polimerase , Streptococcus/genética
17.
Bull World Health Organ ; 79(11): 1006-13, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11731807

RESUMO

OBJECTIVE: To demonstrate the value of a national register for surveillance of services for an inherited disorder. METHODS: Data from the United Kingdom Thalassaemia Register and the United Kingdom Register of Prenatal Diagnosis for Haemoglobin Disorders were combined in a database; these registers include all fetuses known to have been diagnosed with beta thalassaemia major, beta thalassaemia intermedia, or haemoglobin E/beta thalassaemia in the United Kingdom. Data were extracted to show outcomes (selective abortion or live birth) of all fetuses and the status of those born with a disorder (alive, dead, successful bone marrow transplant, or lost to follow-up) by parents' region of residence and ethnicity. FINDINGS: At the end of 1999 the register included 1074 patients, 807 of whom were alive and residing in the United Kingdom. A successful bone marrow transplant has been performed for 117 out of 581 (20%) patients born since 1975. Residents of Pakistani origin are now the main group at risk in the United Kingdom, replacing residents of Cypriot origin. This has led to a marked shift in the need for services from the south-east of England to the Midlands and the north of England. Despite the acceptability of prenatal diagnosis, the proportion of affected births remains 50% higher than would be expected, reflecting a widespread failure to deliver timely screening and counselling to carriers. Even though effective treatment is available the annual number of deaths is rising, indicating that better tolerated treatments are needed. CONCLUSION: A national diagnosis register is a powerful instrument for monitoring the treatment and prevention of inherited disorders and for highlighting correctable shortcomings. In view of the increasing possibilities for genetic screening there is a strong case for central funding for such databases within modern health services.


Assuntos
Vigilância da População , Sistema de Registros , Talassemia beta/epidemiologia , Adolescente , Adulto , Transplante de Medula Óssea , Criança , Pré-Escolar , Feminino , Genoma Humano , Necessidades e Demandas de Serviços de Saúde , Humanos , Pessoa de Meia-Idade , Programas Nacionais de Saúde , Gravidez , Resultado da Gravidez , Diagnóstico Pré-Natal , Qualidade da Assistência à Saúde , Reino Unido/epidemiologia , Talassemia beta/diagnóstico , Talassemia beta/genética , Talassemia beta/terapia
18.
Neuroreport ; 12(18): 4061-4, 2001 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-11742238

RESUMO

This study determined the effects of glutamate uptake inhibition on primary-afferent excitatory postsynaptic potentials (DR-EPSPs) in spinal dorsal horn neurones in vitro from naive rats and rats with localised arthritis. The glutamate uptake inhibitor L-PDC (1 mM) significantly reduced DR-EPSP amplitude and duration with a greater reduction in arthritic than in naive rats. The group II/III selective metabotropic glutamate receptor antagonist CPPG (100 microM) reversed L-PDC-induced DR-EPSP inhibition in naive but not arthritic rats. L-AP4 (30 microM), a group III metabotropic agonist, inhibited DR-EPSPs with no difference between naive and arthritic rats. These data suggest the existence of an autoregulatory feedback mechanism that limits spinal postsynaptic excitation especially during inflammation. The putative contribution of metabotropic glutamate receptors to this phenomenon is discussed.


Assuntos
Sistema X-AG de Transporte de Aminoácidos/metabolismo , Artrite Experimental/metabolismo , Glicina/análogos & derivados , Células do Corno Posterior/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Sistema X-AG de Transporte de Aminoácidos/antagonistas & inibidores , Animais , Ácidos Dicarboxílicos/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Retroalimentação Fisiológica/fisiologia , Ácido Glutâmico/metabolismo , Glicina/farmacologia , Técnicas In Vitro , Inibidores da Captação de Neurotransmissores/farmacologia , Propionatos/farmacologia , Pirrolidinas/farmacologia , Ratos , Ratos Wistar , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
19.
J Antimicrob Chemother ; 48(2): 219-23, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11481291

RESUMO

The in vitro activity of daptomycin was assessed in comparison with that of vancomycin and penicillin against a wide range of Gram-positive aerobic clinical isolates. MICs were determined by an agar dilution method on Mueller-Hinton agar (NCCLS/EUCAST) and on Isotonic agar adjusted to contain 50 mg/L free calcium (BSAC). Both media were enriched with 5% horse blood for fastidious organisms. Daptomycin MICs for all 172 staphylococci, including methicillin-susceptible and methicillin-resistant Staphylococcus aureus, Staphylococcus epidermidis and Staphylococcus haemolyticus, were 0.03-0.5 mg/L. For 99 of the 100 enterococci (Enterococcus faecalis, n = 50; Enterococcus faecium, n = 50), including 37 vancomycin-resistant isolates, they were 0.25-2 mg/L. For all 108 beta-haemolytic streptococci, including Streptococcus pyogenes and Streptococcus agalactiae, daptomycin MICs were 0.016- 0.25 mg/L; for 101 alpha-haemolytic streptococci, including Streptococcus pneumoniae and 'viridans' streptococci, they were 0.016-2 mg/L. For miscellaneous vancomycin-resistant isolates including Lactobacillus spp., Lactococcus spp., Leuconostoc spp., Pediococcus spp. and isolates of Enterococcus casseliflavus and Enterococcus gallinarum, daptomycin MICs were 0.03-2 mg/L; MICs for the seven isolates of Listeria monocytogenes were 0.25-4 mg/L. There was little difference between the results on Mueller-Hinton agar and on supplemented Isotonic agar The discrepant results occasionally obtained tended to be one dilution higher on supplemented Isotonic agar. Daptomycin was active (MICs < or = 2 mg/L) against all the isolates tested with the exception of one isolate each of E. faecium and L. monocytogenes (MICs = 4 mg/L). Our results indicate that daptomycin MICs are independent of methicillin and vancomycin MICs.


Assuntos
Antibacterianos/farmacologia , Bactérias Aeróbias/efeitos dos fármacos , Daptomicina/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/isolamento & purificação , Bactérias Aeróbias/isolamento & purificação , Humanos , Técnicas In Vitro , Testes de Sensibilidade Microbiana , Penicilinas/farmacologia , Vancomicina/farmacologia
20.
Brain Res Dev Brain Res ; 128(2): 177-9, 2001 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-11412903

RESUMO

DCG-IV, a type 2 metabotropic glutamate receptor (mGluR2) agonist, was infused into the main olfactory bulb of 1-week-old pups exposed to peppermint odor. A preference for peppermint was demonstrated 24 h later. The data support the proposal that disinhibition at dendrodendritic synapses between granule cells and mitral cells is a critical component of olfactory memory formation in the rat pup olfactory bulb as well as in the accessory olfactory bulb of adult rodents.


Assuntos
Anticonvulsivantes/farmacologia , Ciclopropanos/farmacologia , Aprendizagem por Discriminação/efeitos dos fármacos , Glicina/farmacologia , Bulbo Olfatório/fisiologia , Receptores de Glutamato Metabotrópico/agonistas , Animais , Animais Recém-Nascidos , Condicionamento Psicológico/efeitos dos fármacos , Condicionamento Psicológico/fisiologia , Glicina/análogos & derivados , Memória/efeitos dos fármacos , Memória/fisiologia , Mentha piperita , Microinjeções , Inibição Neural/efeitos dos fármacos , Inibição Neural/fisiologia , Odorantes , Bulbo Olfatório/citologia , Bulbo Olfatório/efeitos dos fármacos , Neurônios Receptores Olfatórios/efeitos dos fármacos , Neurônios Receptores Olfatórios/fisiologia , Extratos Vegetais , Ratos , Ratos Sprague-Dawley , Receptores de Glutamato Metabotrópico/fisiologia , Olfato/fisiologia , Ácido gama-Aminobutírico/fisiologia
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