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1.
J Intellect Disabil Res ; 67(2): 123-135, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36437706

RESUMO

BACKGROUND: There is a paucity of research regarding the attitudes of coaches towards training athletes with intellectual disabilities (ID). This is particularly evident for coaches working with athletes with ID that are competing in the innovative Special Olympics (SO) Unified Sports programme. Research on the inclusive impact of sport plays a significant role, not only in sports development but also in the training of sports professionals and coaches, as a sufficient amount of special coaching experience is required to achieve inclusion. For this reason, this study was conducted among professionals coaching tennis with athletes with ID. The purpose of this study was to analyse the attitudes of tennis coaches working with athletes with ID in the SO tennis programme. METHODS: The study was conducted on a sample of internationally recognised elite tennis coaches (n = 78) working with tennis players with ID at two international tennis competitions. A questionnaire and a structured interview were conducted with the coaches to examine the sociometric characteristics of the coaches involved in the research. Findings were then compared with views on professional statements for similarities and differences in their attitudes towards their athletes and their work. RESULTS: Results indicated that coaches felt the most important criteria for a coach working successfully with athletes with ID were (1) a wide range of knowledge, (2) professional expertise, (3) social sensitivity, (4) positive attitude and (5) motivation. Results supported the existing theoretical findings that besides professional expertise and experience, a basic knowledge about disability is needed among coaches working with athletes with ID. CONCLUSIONS: This research was unique in the international scene, in that, although the number of tennis coaches working within the movement of SO is relatively high, to this date, no scientific survey has been focused on them.


Assuntos
Pessoas com Deficiência , Deficiência Intelectual , Esportes , Tênis , Humanos , Atletas , Atitude
2.
Bull Math Biol ; 77(10): 1886-908, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26403421

RESUMO

We employ partial integro-differential equations to model trophic interaction in a spatially extended heterogeneous environment. Compared to classical reaction-diffusion models, this framework allows us to more realistically describe the situation where movement of individuals occurs on a faster time scale than on the demographic (population) time scale, and we cannot determine population growth based on local density. However, most of the results reported so far for such systems have only been verified numerically and for a particular choice of model functions, which obviously casts doubts about these findings. In this paper, we analyse a class of integro-differential predator-prey models with a highly mobile predator in a heterogeneous environment, and we reveal the main factors stabilizing such systems. In particular, we explore an ecologically relevant case of interactions in a highly eutrophic environment, where the prey carrying capacity can be formally set to 'infinity'. We investigate two main scenarios: (1) the spatial gradient of the growth rate is due to abiotic factors only, and (2) the local growth rate depends on the global density distribution across the environment (e.g. due to non-local self-shading). For an arbitrary spatial gradient of the prey growth rate, we analytically investigate the possibility of the predator-prey equilibrium in such systems and we explore the conditions of stability of this equilibrium. In particular, we demonstrate that for a Holling type I (linear) functional response, the predator can stabilize the system at low prey density even for an 'unlimited' carrying capacity. We conclude that the interplay between spatial heterogeneity in the prey growth and fast displacement of the predator across the habitat works as an efficient stabilizing mechanism. These results highlight the generality of the stabilization mechanisms we find in spatially structured predator-prey ecological systems in a heterogeneous environment.


Assuntos
Eutrofização , Cadeia Alimentar , Animais , Ecossistema , Meio Ambiente , Conceitos Matemáticos , Modelos Biológicos
3.
J Anim Breed Genet ; 132(2): 100-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25823836

RESUMO

GRain is freely available software intended to enable and promote testing of hypotheses with respect to purging and heterogeneity of inbreeding depression. The program is based on a stochastic approach, the gene dropping method, and calculates various coefficients from large and complex pedigrees. GRain calculates, together with the 'classical' inbreeding coefficient, ancestral inbreeding coefficients proposed by Ballou, (1997) J. Hered., 88, 169 and Kalinowski et al., (2000) Conserv. Biol., 14, 1375 as well as an ancestral history coefficient (AHC ), defined here for the first time. AHC is defined as the number that tells how many times during pedigree segregation (gene dropping) a randomly taken allele has been in IBD status. Furthermore, GRain enables testing of heterogeneity and/or purging of inbreeding depression with respect to different founders/ancestors by calculating partial coefficients for all previously obtained coefficients.


Assuntos
Endogamia , Software , Animais , Genética Populacional , Linhagem
4.
J Anim Breed Genet ; 130(4): 303-11, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23855632

RESUMO

In a synthetic closed population of Pannon White rabbits, additive (VA ), dominance (VD ) and permanent environmental (VPe ) variance components as well as doe (bF d ) and litter (bF l ) inbreeding depression were estimated for the number of kits born alive (NBA), number of kits born dead (NBD) and total number of kits born (TNB). The data set consisted of 18,398 kindling records of 3883 does collected from 1992 to 2009. Six models were used to estimate dominance and inbreeding effects. The most complete model estimated VA and VD to contribute 5.5 ± 1.1% and 4.8 ± 2.4%, respectively, to total phenotypic variance (VP ) for NBA; the corresponding values for NBD were 1.9 ± 0.6% and 5.3 ± 2.4%, for TNB, 6.2 ± 1.0% and 8.1 ± 3.2% respectively. These results indicate the presence of considerable VD . Including dominance in the model generally reduced VA and VPe estimates, and had only a very small effect on inbreeding depression estimates. Including inbreeding covariates did not affect estimates of any variance component. A 10% increase in doe inbreeding significantly increased NBD (bF d  = 0.18 ± 0.07), while a 10% increase in litter inbreeding significantly reduced NBA (bF l  = -0.41 ± 0.11) and TNB (bF l  = -0.34 ± 0.10). These findings argue for including dominance effects in models of litter size traits in populations that exhibit significant dominance relationships.


Assuntos
Variação Genética , Endogamia , Tamanho da Ninhada de Vivíparos/genética , Animais , Modelos Genéticos , Fenótipo , Coelhos
5.
Mar Pollut Bull ; 188: 114648, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36724670

RESUMO

Estuaries in rainfall poor regions are highly susceptible to climatic and hydrological changes. The Coorong, a Ramsar-listed estuarine-coastal lagoon at the end of the Murray-Darling Basin (Australia), has experienced declining ecological health over recent decades. Twenty years of environmental data were analysed to assess patterns and drivers of water quality changes. Large areas of the Coorong are now persistently hyper-saline (salinity >80 psu) and hypereutrophic (total nitrogen, TN > 4 mg L-1, total phosphorus, TP > 0.2 mg L-1, chlorophyll a > 50 µg L-1) which coincided with reduced flushing due to diminished freshwater inflows and increasing evapo-concentration. Sediment quality also was related to flushing, with higher concentrations of organic carbon, TN, TP and sulfides as salinity increased. While total nutrient levels are very high, dissolved inorganic nutrients are generally low. Increased lagoonal flushing would be beneficial to reduce the hypersalinisation and hypereutrophication and improve ecosystem health.


Assuntos
Ecossistema , Rios , Clorofila A/análise , Eutrofização , Austrália , Nitrogênio/análise , Fósforo/análise , Monitoramento Ambiental , Clorofila/análise
6.
Physiol Int ; 107(1): 55-66, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32598332

RESUMO

Numerous studies indicate that smoking during pregnancy exerts harmful effects on fetal brain development. The aim of this study was to determine the influence of maternal smoking during pregnancy on the early physical and neurobehavioral development of newborn rats. Wistar rats were subjected to whole-body smoke exposure for 2 × 40 min daily from the day of mating until day of delivery. For this treatment, a manual closed-chamber smoking system and 4 research cigarettes per occasion were used. After delivery the offspring were tested daily for somatic growth, maturation of facial characteristics and neurobehavioral development until three weeks of age. Motor coordination tests were performed at 3 and 4 weeks of age. We found that prenatal cigarette smoke exposure did not alter weight gain or motor coordination. Critical physical reflexes indicative of neurobehavioral development (eyelid reflex, ear unfolding) appeared significantly later in pups prenatally exposed to smoke as compared to the control group. Prenatal smoke exposure also resulted in a delayed appearance of reflexes indicating neural maturity, including hind limb grasping and forelimb placing reflexes. In conclusion, clinically relevant prenatal exposure to cigarette smoke results in slightly altered neurobehavioral development in rat pups. These findings suggest that chronic exposure of pregnant mothers to cigarette smoke (including passive smoking) results in persisting alterations in the developing brain, which may have long-lasting consequences supporting the concept of developmental origins of health and disease (DoHAD).


Assuntos
Comportamento Animal/efeitos dos fármacos , Doenças do Sistema Nervoso/patologia , Efeitos Tardios da Exposição Pré-Natal/patologia , Fumar/efeitos adversos , Animais , Animais Recém-Nascidos , Peso Corporal , Modelos Animais de Doenças , Feminino , Masculino , Atividade Motora/fisiologia , Doenças do Sistema Nervoso/induzido quimicamente , Gravidez , Efeitos Tardios da Exposição Pré-Natal/etiologia , Efeitos Tardios da Exposição Pré-Natal/psicologia , Ratos , Ratos Wistar , Reflexo/fisiologia
7.
Aquat Toxicol ; 227: 105582, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32823071

RESUMO

While it is likely that ENPs may occur together with other contaminants in nature, the combined effects of exposure to both ENPs and environmental contaminants are not studied sufficiently. In this study, we investigated the acute and sublethal toxicity of PVP coated silver nanoparticles (AgNP) and ionic silver (Ag+; administered as AgNO3) to the marine copepod Calanus finmarchicus. We further studied effects of single exposures to AgNPs (nominal concentrations: low 15 µg L-1 NPL, high 150 µg L-1 NPH) or Ag+ (60 µg L-1), and effects of co-exposure to AgNPs, Ag+ and the water-soluble fraction (WSF; 100 µg L-1) of a crude oil (AgNP + WSF; Ag++WSF). The gene expression and the activity of antioxidant defense enzymes SOD, CAT and GST, as well as the gene expression of HSP90 and CYP330A1 were determined as sublethal endpoints. Results show that Ag+ was more acutely toxic compared to AgNPs, with 96 h LC50 concentrations of 403 µg L-1 for AgNPs, and 147 µg L-1 for Ag+. Organismal uptake of Ag following exposure was similar for AgNP and Ag+, and was not significantly different when co-exposed to WSF. Exposure to AgNPs alone caused increases in gene expressions of GST and SOD, whereas WSF exposure caused an induction in SOD. Responses in enzyme activities were generally low, with significant effects observed only on SOD activity in NPL and WSF exposures and on GST activity in NPL and NPH exposures. Combined AgNP and WSF exposures caused slightly altered responses in expression of SOD, GST and CYP330A1 genes compared to the single exposures of either AgNPs or WSF. However, there was no clear pattern of cumulative effects caused by co-exposures of AgNPs and WSF. The present study indicates that the exposure to AgNPs, Ag+, and to a lesser degree WSF cause an oxidative stress response in C. finmarchicus, which was slightly, but mostly not significantly altered in combined exposures. This indicated that the combined effects between Ag and WSF are relatively limited, at least with regard to oxidative stress.


Assuntos
Copépodes/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Petróleo/toxicidade , Prata/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Copépodes/genética , Copépodes/metabolismo , Interações Medicamentosas , Expressão Gênica/efeitos dos fármacos , Íons , Nanopartículas Metálicas/química , Estresse Oxidativo/genética , Água do Mar/química , Prata/química , Solubilidade , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda , Poluentes Químicos da Água/química
8.
Neurotox Res ; 12(2): 85-93, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17967732

RESUMO

Monosodium glutamate (MSG) treatment of neonatal rodents leads to degeneration of the neurons in the arcuate nucleus, inner retinal layers and various other brain areas. It also causes various changes in the motor activity, sensory performance and learning abilities. We have previously shown that MSG treatment delays the appearance of some reflexes during neurobehavioral development and leads to temporary changes in reflex performance and motor coordination. Investigation of novelty-seeking behavior is of growing importance for its relationship with sensitivity to psychomotor stimulants. Perinatal administration of numerous toxic agents has been shown to influence novelty-seeking behavior in rats, but little is known about the influence of neonatal MSG treatment on the novelty-seeking behavior. The aim of the present study was to compare changes in locomotor, spontaneous exploratory and novelty-seeking behavior in periadolescent rats neonatally treated with MSG. Newborn rats were treated with 4 mg/g MSG subcutaneously on postnatal days 1, 3, 5, 7 and 9. Open-field behavior was tested at 2, 3, 4, 6 and 8 weeks of age. We found that MSG administration led to only temporary increases in locomotor behavior, which was more pronounced during the first few postnatal weeks, followed by a subtle hypoactivity at 2 months of age. Novelty-seeking was tested in four 5-min trials at 3 weeks of age. Trial 1 was in an empty open-field, two identical objects were placed in the arena during trial 2 and 3, and one of them was replaced to a novel object during trial 4. We found that the behavioral pattern of MSG-treated rats was the opposite in all tested signs in the novelty exploration test compared to control pups. In summary, our present study shows that neonatal MSG treatment leads to early temporary changes in the locomotor activity followed by hypoactivity at 2 months of age. Furthermore, MSG-treated rats show a markedly disturbed novelty-seeking behavior represented by altered activity when subjected to a novel object.


Assuntos
Comportamento Exploratório/efeitos dos fármacos , Aditivos Alimentares/farmacologia , Atividade Motora/efeitos dos fármacos , Glutamato de Sódio/farmacologia , Fatores Etários , Análise de Variância , Animais , Animais Recém-Nascidos , Comportamento Animal/efeitos dos fármacos , Feminino , Masculino , Ratos , Ratos Wistar
9.
Biochim Biophys Acta ; 1245(3): 305-10, 1995 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-8541305

RESUMO

In vivo generated nitric oxide, NO, circulates in plasma mainly as an S-nitroso adduct of serum albumin. Compared to free NO, this NO-adduct is relatively long-lived. It exerts EDRF-like effects of vasodilation and platelet inhibition. Free NO is directly inactivated ('quenched') by advanced glycosylation end products (AGEs), glucose-derived protein moieties that form nonenzymatically and accumulate primarily on long-lived tissue proteins. They have been implicated in many of the long-term complications of diabetes mellitus. We found that the antiproliferative effects of thiol-stabilized NO (SNO-BSA) on Con A-stimulated lymphocytes from peripheral blood were even stronger than those of the NO-generating drug SNAP. The antimitogenic activity of SNO-BSA, however, was not significantly enhanced by the low molecular weight NO-carrier glutathione. NO liberated from SNO-BSA in molar excess was almost completely quenched by AGE-BSA. NO-dependent activating effects such as enhanced rate of glucose uptake or generation of cGMP in resting peripheral mononuclear cells (PBMC) and the antiproliferative activity of the NO-carrier BSA on Con A-stimulated cells were thereby abolished. In contrast, advanced glycosylation impaired the ability of BSA to function as NO-carrier, as evidenced by the lack of antiproliferative activity of NO-AGE-BSA and its inability to activate glucose transport or cGMP generation.


Assuntos
Proteínas Sanguíneas/metabolismo , Leucócitos Mononucleares/metabolismo , Óxido Nítrico/metabolismo , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Glucose/metabolismo , Glicosilação , Humanos , Óxido Nítrico/farmacologia , Penicilamina/análogos & derivados , Penicilamina/farmacologia , S-Nitroso-N-Acetilpenicilamina , Soroalbumina Bovina/metabolismo , Vasodilatadores/farmacologia
10.
J Clin Oncol ; 19(2): 551-7, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11208850

RESUMO

PURPOSE: Lesion volume is often used as an end point in clinical trials of oncology therapy. We sought to compare the common method of using orthogonal diameters to estimate lesion volume (the diameter method) with a computer-assisted planimetric technique (the perimeter method). METHODS: Radiologists reviewed 825 magnetic resonance imaging studies from 219 patients with glioblastoma multiforme. Each study had lesion volume independently estimated via the diameter and perimeter methods. Cystic areas were subtracted out or excluded from the outlined lesion. Inter- and intrareader variability was measured by using multiple readings on 48 cases. Where serial studies were available in noncystic cases, a mock response analysis was used. RESULTS: The perimeter method had a reduced interreader and intrareader variability compared with the diameter method (using SD of differences): intrareader, 1.76 mL v 7.38 mL (P < .001); interreader, 2.51 mL v 9.07 mL (P < .001) for perimeter and diameter results, respectively. Of the 121 noncystic cases, 23 had serial data. In six (26.1%) of those 23, a classification difference occurred when the perimeter method was used versus the diameter method. CONCLUSION: Variability of measurements was reduced with the computer-assisted perimeter method compared with the diameter method, which suggests that changes in volume can be detected more accurately with the perimeter method. The differences between these techniques seem large enough to have an impact on grading the response to therapy.


Assuntos
Neoplasias Encefálicas/diagnóstico , Encéfalo/patologia , Glioblastoma/diagnóstico , Imageamento por Ressonância Magnética , Análise Numérica Assistida por Computador , Humanos , Modelos Teóricos , Variações Dependentes do Observador
11.
Sci Total Environ ; 511: 469-76, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25574974

RESUMO

Nanoparticles are emerging contaminants of concern. Knowledge on their environmental impacts is scarce, especially on their interactive effects with other contaminants. In this study we investigated effects of titanium dioxide nanoparticles (TiO2NP) on the blue mussel (Mytilus edulis) and determined their influence on the bioavailability and toxicity of benzo(a)pyrene (B(a)P), a carcinogenic polyaromatic hydrocarbon (PAH). Blue mussels were exposed to either TiO2NP (0.2 and 2.0 mg L(-1)) or B(a)P (20 µg L(-1)) and to the respective combinations of these two compounds. Aqueous contaminant concentrations, the uptake of Ti and B(a)P into mussel soft tissue, effects on oxidative stress and chromosomal damage were analyzed. The uncoated TiO2NP agglomerated rapidly in the seawater. The presence of TiO2NP significantly reduced the bioavailability of B(a)P, shown by lowered B(a)P concentrations in exposure tanks and in mussel tissue. The activities of antioxidant enzyme superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were impacted by the various exposure regimes, indicating oxidative stress in the contaminant exposure groups. While SOD activity was increased only in the 0.2TiO2NP exposure group, CAT activity was enhanced in both combined exposure groups. The GPx activity was increased only in the groups exposed to the two single compounds. In hemocytes, increased chromosomal damage was detected in mussels exposed to the single compounds, which was further increased after exposure to the combination of compounds. In this study we show that the presence of TiO2NP in the exposure system reduced B(a)P uptake in blue mussels. However, since most biomarker responses did not decrease despite of the lower B(a)P uptake in combined exposures, the results suggest that TiO2NP can act as additional stressor, or potentially alters B(a)P toxicity by activation.


Assuntos
Benzo(a)pireno/toxicidade , Mytilus edulis/fisiologia , Nanopartículas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Benzo(a)pireno/metabolismo , Biomarcadores/metabolismo , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Nanopartículas/química , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Titânio/química , Poluentes Químicos da Água/metabolismo
12.
Stroke ; 32(9): 2021-8, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11546891

RESUMO

BACKGROUND AND PURPOSE: The goal of this study was to evaluate the utility of perfusion-weighted CT (PWCT) in predicting final infarct volume and clinical outcome in patients with acute middle cerebral artery (MCA) stroke. METHODS: Twenty-two consecutive patients with MCA stem occlusion who underwent intra-arterial thrombolysis within 6 hours of stroke onset had noncontrast CT and CT angiography with whole-brain PWCT imaging before treatment. Infarct volumes were computed from the initial PWCT and follow-up scans; clinical outcome was measured with the modified Rankin scale. RESULTS: Initial PWCT lesion volumes correlated significantly with final infarct volume (P=0.0002) and clinical outcome (P=0.01). For the 10 patients with complete recanalization, the relationship between initial and final lesion volume was especially strong (R(2)=0.94, P<0.0001, slope of regression line=0.92). For those without complete recanalization, there was progression of lesion volume on follow-up imaging (R(2)=0.50, P=0.01, slope of regression line=1.61). All patients with either initial PWCT lesion volumes >100 mL or no recanalization had poor outcomes (Rankin scores, 4 to 6). Mean admission NIH Stroke Scale scores and mean lesion volumes in the poor outcome group were significantly different compared with the good or fair outcome (Rankin scores, 0 to 3) group (21+/-4 versus 17+/-5, P=0.05, and 106+/-79 versus 29+/-37 mL, P=0.01). Patients with initial volumes <100 mL and partial or complete recanalization all had good (Rankin scores, 0 to 2) or fair (Rankin score, 3) outcomes. CONCLUSIONS: Lesion volumes on admission PWCT images approximate final infarct volume for patients with early complete recanalization of MCA stem occlusion. For those without complete recanalization, there is subsequent enlargement of lesion volume on follow-up. Initial PWCT lesion volumes also have predictive value; volumes >100 mL are associated with a poor clinical outcome. In these highly selected patients, initial PWCT lesion volume was a stronger predictor of clinical outcome than was initial NIH Stroke Scale score.


Assuntos
Infarto Cerebral/diagnóstico por imagem , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Infarto da Artéria Cerebral Média/terapia , Terapia Trombolítica , Tomografia Computadorizada por Raios X/métodos , Doença Aguda , Idoso , Velocidade do Fluxo Sanguíneo , Volume Sanguíneo , Infarto Cerebral/etiologia , Circulação Cerebrovascular , Demografia , Feminino , Humanos , Infarto da Artéria Cerebral Média/complicações , Masculino , Valor Preditivo dos Testes , Intensificação de Imagem Radiográfica , Resultado do Tratamento
13.
Clin Pharmacol Ther ; 26(5): 660-7, 1979 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-498708

RESUMO

The effects of allopurinol on the plasma clearance and metabolism of theophylline in man were investigated under single-dose and multiple-dosing conditions. No change in theophylline clearance was found with the concomitant use of allopurinol but 1-methylxanthine (1MX), a theophylline metabolite not previously described in man, was detected in urine during control and allopurinol treatment phases under both single- and multiple-dosing conditions. 1MX excretion increased at the expense of 1-methyluric acid (1MU) during the allopurinol treatment phase. It is proposed that the secondary biotransformation of 1MX to 1MU is mediated by xanthine oxidase.


Assuntos
Alopurinol , Teofilina/metabolismo , Adulto , Esquema de Medicação , Humanos , Cinética , Masculino , Fumar , Teofilina/sangue , Teofilina/urina , Xantinas/urina
14.
Am J Med ; 93(3): 277-82, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1524079

RESUMO

PURPOSE: A prospective randomized study was conducted over a 23-month period in an adult medical-surgical intensive care unit to determine whether triple-lumen catheters reduce the need for peripheral vascular access and whether they are associated with a higher rate of infection than single-lumen catheters. PATIENTS AND METHODS: After the insertion route, internal jugular or subclavian, was selected by the physician, patients were randomized either to single-lumen or triple-lumen catheter groups. Complementary peripheral vascular access was allowed in both groups. Catheters were removed according to preestablished defined reasons: suspicion of catheter-related sepsis, uselessness of central venous access, duration of catheterization of more than 21 days, discharge from the intensive care unit, or death. RESULTS: Data on 129 central venous catheters were collected from 91 consecutive patients. Twenty-five of 68 patients from the single-lumen group and 1 of 61 patients from the triple-lumen group needed peripheral vascular access (p less than 0.001). Catheter-related sepsis rates, defined either by clinical signs and positive qualitative tip cultures (8.9% versus 11.5%) or by quantitative tip cultures (16.2% versus 11.5%), were identical in the single-lumen and triple-lumen groups (type II error: 8%). CONCLUSION: In intensive care units, the use of triple-lumen catheters is associated with a dramatic decrease in the need for peripheral vascular access. The incidence of central venous catheter-related sepsis appears identical for single- and triple-lumen catheters.


Assuntos
Cateterismo Venoso Central/instrumentação , Cateteres de Demora/efeitos adversos , Cuidados Críticos/métodos , Infecções/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cateterismo Venoso Central/efeitos adversos , Estado Terminal , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
15.
Biotechniques ; 21(6): 1110-4, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8969840

RESUMO

A low order neural network-based filter was designed as a rapid screening agent for single-spanning transmembrane regions in an integrated informatics system. A rapid screening algorithm was seen as a compromise between costly structure-specific techniques and simple rules that gave a high false-positive rate for cDNA. The filter was applied to a library of 2123 anonymous cDNA sequences, which resulted in 61 detections. Evaluation of the detections with two other dissimilar computer prediction algorithms yielded strong transmembrane predictions for 15 of the detections, while 8 of the detections resulted in a definitive negative result. Homology searches performed on the sequences with detection reports yielded 13 homologs in the predicted reading frame, four of which are membrane associated.


Assuntos
DNA Complementar/isolamento & purificação , Testes Genéticos/métodos , Redes Neurais de Computação , Animais , Inteligência Artificial , Sequência de Bases , Reações Falso-Positivas , Biblioteca Gênica , Projeto Genoma Humano , Humanos , Dados de Sequência Molecular , Valor Preditivo dos Testes
16.
Chest ; 114(1): 207-13, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9674471

RESUMO

OBJECTIVE: To evaluate the incidence and risk factors for catheter-related central vein thrombosis in ICU patients. DESIGN: Observational prospective multicenter study. SETTING: An 8-bed surgical ICU, a 10-bed surgical cardiovascular ICU, and a 10-bed medical-surgical ICU. PATIENTS: During an 18-month period, 265 internaljugular or subclavian catheters were included. Veins were explored by duplex scanning performed just before or < 24 h after catheter removal. Suspected risk factors of catheter-related central vein thrombosis were recorded. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Fifty-seven catheters were excluded from the analysis. Therefore 208 catheters were analyzed. Mean age of patients was 64+/-15 years, simplified acute physiologic score was 12+/-5, organ system failure score at insertion was 1+/-1, and mean duration of catheterization was 9+/-5 days. A catheter-related internal jugular or subclavian vein thrombosis occurred in 33% of the cases (42% [95% confidence interval (CI), 34 to 49%] and 10% [95% CI, 3 to 18%], respectively). Thrombosis was limited in 8%, large in 22%, and occlusive in 3% of the cases. Internal jugular route (relative risk [RR], 4.13; 95% CI, 1.72 to 9.95), therapeutic heparinization (RR 0.47; 95% CI, 0.23 to 0.99), and age >64 years (RR, 2.44; 95% CI, 2.05 to 3.19) were independently associated with catheter-related thrombosis. Moreover, the risk of catheter-related sepsis was 2.62-fold higher when thrombosis occurred (p=0.011). CONCLUSIONS: Catheter-related central vein thrombosis is a frequent complication of central venous catheterization in ICU patients and is closely associated with catheter-related sepsis.


Assuntos
Cateterismo Venoso Central/instrumentação , Cuidados Críticos , Veias Jugulares , Sepse/etiologia , Veia Subclávia , Trombose/etiologia , APACHE , Infecções por Acinetobacter , Fatores Etários , Idoso , Anticoagulantes/uso terapêutico , Cateterismo Venoso Central/efeitos adversos , Intervalos de Confiança , Enterobacter , Infecções por Enterobacteriaceae , Feminino , Heparina/uso terapêutico , Humanos , Incidência , Veias Jugulares/diagnóstico por imagem , Infecções por Klebsiella , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Infecções por Pseudomonas , Fatores de Risco , Infecções por Serratia , Infecções Estafilocócicas , Veia Subclávia/diagnóstico por imagem , Trombose/classificação , Fatores de Tempo , Ultrassonografia Doppler Dupla
17.
Arch Surg ; 128(3): 284-8, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8442683

RESUMO

Routine aneurysm culture is frequently performed as it is thought that a positive culture could be a risk factor for secondary graft infection. Five hundred aneurysms, in a series of 796 patients, had microbiologic examination of the thrombus and/or aneurysm wall. Cultures were positive in 185 cases (37%), mostly due to normal skin flora microorganisms (80%), whereas 16 patients (3.2%) had infectious aortitis. Gram-stained smears were positive in nine of these 16 patients compared with two of the other 169. Of the 185 patients with positive culture, after a mean length of follow-up of 35 months, only one had a graft infection that occurred 6 years later and was not due to the same microorganism. Graft sepsis was diagnosed in six of the 296 patients who did not have a positive culture, and was related to clinically obvious locoregional or systemic foci. In this series, positive cultures from aneurysm without rupture or signs of infection were not a risk factor for secondary graft sepsis. Therefore, in cases of asymptomatic unruptured aneurysm, routine culturing is not necessary as a positive result has no pathogenic significance or therapeutic implication.


Assuntos
Aorta Abdominal/microbiologia , Aneurisma da Aorta Abdominal/microbiologia , Bactérias/isolamento & purificação , Infecção da Ferida Cirúrgica/etiologia , Trombose/microbiologia , Idoso , Antibacterianos/uso terapêutico , Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/microbiologia , Aortite/microbiologia , Corynebacterium/isolamento & purificação , Feminino , Seguimentos , Humanos , Incidência , Masculino , Estudos Retrospectivos , Fatores de Risco , Infecções Estafilocócicas , Staphylococcus/isolamento & purificação , Infecção da Ferida Cirúrgica/prevenção & controle
18.
Peptides ; 20(11): 1321-6, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10612446

RESUMO

Previously, the opioid peptide Tyr-D-Ala-Gly-(NMe)Phe-CH2Cl (DAMCK) has been shown to bind irreversibly to mu opioid receptors in vitro. In the present work, the antinociceptive effect of DAMCK has been evaluated. Rats treated systemically with DAMCK (1-100 pg/kg) displayed a dose-dependent increase in tail-flick analgesia that peaked by 15 min, then stayed about the same until 60 min, followed by some decrease over time. Higher doses of DAMCK (10 ng/kg-100 microg/kg) produced a near-maximal antinociceptive effect that remained stable for 4 h. Significant antinociception was still detected 8 h, but not 24 h postinjection. In comparison, the parent peptide DAMGO (Tyr-D-Ala-Gly-(NMe)Phe-Gly-ol) reached maximal effect by about 30 min, followed by a rapid cessation of its antinociceptive response. Naloxone administered before DAMCK antagonized the antinociceptive response of DAMCK, indicating that it was mediated via opioid receptors. Naloxone administered 45 min after DAMCK attenuated the tail-flick response to some extent, but a substantial part (40-60% depending on the peptide concentration and evaluation time) remained unaffected. Central administration of DAMCK also elicited time- and concentration-dependent, profound, opioid receptor mediated, apparently irreversible antinociception.


Assuntos
Clorometilcetonas de Aminoácidos/farmacologia , Analgésicos/farmacologia , Clorometilcetonas de Aminoácidos/administração & dosagem , Analgésicos/administração & dosagem , Animais , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Injeções Intravenosas , Injeções Intraventriculares , Masculino , Ratos , Ratos Wistar
19.
Neurosci Lett ; 328(1): 5-8, 2002 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-12123846

RESUMO

Nociceptin/orphanin FQ (N/OFQ) is a 17-amino acid endogenous neuropeptide ligand for the nociceptin receptor (NOP). We have prepared a [(3)H]-labelled truncated N/OFQ peptide, [(3)H]N/OFQ(1-13)NH(2) and compared its binding characteristics with [(3)H]N/OFQ(1-17)OH and [(125)I]Y(14)N/OFQ(1-17)OH in membranes prepared from Chinese hamster ovary cells expressing the recombinant human NOP (CHO(hNOP)) and the rat cerebrocortex. [(3)H]N/OFQ(1-13)NH(2), [(3)H]N/OFQ(1-17)OH and [(125)I]Y(14)N/OFQ(1-17)OH binding to CHO(hNOP) was concentration dependent and saturable with receptor density (B(max)) and radioligand equilibrium dissociation constant (pK(d)) values (mean +/- SEM) of 1043 +/- 58 fmol/mg protein and 10.35 +/- 0.03, 1348 +/- 44 fmol/mg protein and 10.06 +/- 0.04, and 1169 +/- 76 fmol/mg protein and 10.45 +/- 0.06, respectively. In the rat, B(max) and pK(d) values for [(3)H]N/OFQ(1-13)NH(2) and [(3)H]N/OFQ(1-17)OH were 130 +/- 1 fmol/mg protein and 10.70 +/- 0.03, and 157 +/- 4 fmol/mg protein and 10.34 +/- 0.02, respectively. The binding of all radioligands was displaced by a range of peptide and non-peptide ligands. There was a strong correlation (r(2) = 0.92, P = 0.002) between pK(i) values estimated with [(3)H]N/OFQ(1-13)NH(2) and [(3)H]N/OFQ(1-17)OH. No such correlation was observed in comparison with the [(125)I]-labelled peptide (poor agreement with low affinity N/OFQ(1-9)NH(2), Dynorphin-A and Naloxone benzoylhydrazone). We suggest that [(3)H]N/OFQ(1-13)NH(2) may be a useful alternative to [(3)H]N/OFQ(1-17)OH.


Assuntos
Membrana Celular/metabolismo , Córtex Cerebral/metabolismo , Neurônios/metabolismo , Peptídeos Opioides/metabolismo , Receptores Opioides/metabolismo , Animais , Sítios de Ligação/fisiologia , Células CHO , Cricetinae , Humanos , Radioisótopos do Iodo , Fragmentos de Peptídeos/metabolismo , Ligação Proteica/fisiologia , Ensaio Radioligante/métodos , Ratos , Proteínas Recombinantes de Fusão/metabolismo , Frações Subcelulares , Trítio , Receptor de Nociceptina , Nociceptina
20.
AJNR Am J Neuroradiol ; 20(8): 1491-9, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10512236

RESUMO

BACKGROUND AND PURPOSE: The various stages of multiple sclerosis (MS) are characterized by de- and remyelination as well as by inflammation. Diffusion MR imaging is sensitive to tissue water motion, which might correspond to these pathologic processes. Our purpose was to demonstrate differences in apparent diffusion coefficient (ADC) and diffusion tensor anisotropy in acute and chronic MS plaques and in normal-appearing brain. METHODS: Twelve MS patients underwent conventional and full-tensor diffusion MR imaging with B = 1221 s/mm2. Derivation of trace ADC and calculation of anisotropic scalars, including eccentricity, relative anisotropy (RA), and fractional anisotropy (FA) was performed on a per-pixel basis. Regions of interest of plaques and normal structures were determined on coregistered maps. MS lesions were classified as acute, subacute, or chronic on the basis of their appearance on conventional images and in relation to clinical findings. RESULTS: Seven patients had acute plaques with a concentric arrangement of alternating high and low signal intensity on diffusion-weighted images. In nine acute lesions, plaque centers had high ADC with reduced anisotropy compared with rim, normal-appearing white matter (NAWM), and chronic lesions. The thin rim of diffusion-weighted hyperintensity surrounding the center showed variable ADC and anisotropic values, which were not statistically different from NAWM. Subacute and chronic MS lesions had intermediate ADC elevations/anisotropic reductions. Calculated FA pixel maps were superior to eccentricity or RA maps; however, quality was limited by signal-to-noise constraints. CONCLUSION: ADC and diffusion anisotropic scalars reflect biophysical changes in the underlying pathology of the demyelinating process.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Esclerose Múltipla Crônica Progressiva/diagnóstico , Esclerose Múltipla Recidivante-Remitente/diagnóstico , Adolescente , Adulto , Anisotropia , Encéfalo/patologia , Difusão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
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