Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 264
Filtrar
1.
Osteoarthritis Cartilage ; 24(11): 1875-1882, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27349459

RESUMO

OBJECTIVE: To evaluate the extent to which elective total hip arthroplasty (THA) and total knee arthroplasty (TKA) for osteoarthritis (OA) restore normal patient-reported physical function in men and women. METHODS: Pain and physical function (WOMAC-PF) were prospectively measured pre- and post-operatively. The relationship between surgical procedure and achieving physical function equivalent to age and sex-matched adults with no hip or knee joint problems was modeled using sex-specific logistic regression. Percent change in function was also compared between groups using sex-specific generalized linear models adjusted for age, BMI, pain, comorbid conditions, time from surgery, and subsequent surgery. RESULTS: Individuals with pre- and post-operative WOMAC data were classified exclusively into either THA (287M:306F) or TKA (239M:424F) groups. The median follow-up was 476 (THA) and 474 (TKA) days for men, and 495 (THA) and 526 (TKA) days for women. MAIN OUTCOME: women with THA compared with TKA were more likely to achieve a normal level of postoperative PF while there were no significant differences between procedures in men. Additional analyses: we found slightly lower preoperative PF in THA compared with TKA. This difference resolved postoperatively in men, but women who underwent THA reported greater improvement and better PF than those who had TKA. CONCLUSION: In women, THA results in greater improvement in WOMAC-PF at approximately 1-year follow-up and better approximates physical function of community-dwelling older adults without OA than TKA does. In contrast, in men, a lack of between-group post-operative WOMAC-PF differences suggests that procedures result in a similar degree of improvement.


Assuntos
Artroplastia do Joelho , Artroplastia de Quadril , Feminino , Humanos , Articulação do Joelho , Masculino , Osteoartrite , Dor
2.
Regul Toxicol Pharmacol ; 70(2 Suppl): S58-68, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24979735

RESUMO

CD-1 mice were exposed to baseline gasoline vapor condensate (BGVC) alone or to vapors of gasoline blended with methyl tertiary butyl ether (G/MTBE). Inhalation exposures were 6h/d on GD 5-17 at levels of 0, 2000, 10,000, and 20,000mg/m(3). Dams were evaluated for evidence of maternal toxicity, and fetuses were weighed, sexed, and evaluated for external, visceral, and skeletal anomalies. Exposure to 20,000mg/m(3) of BGVC produced slight reductions in maternal body weight/gain and decreased fetal body weight. G/MTBE exposure did not produce statistically significant maternal or developmental effects; however, two uncommon ventral wall closure defects occurred: gastroschisis (1 fetus at 10,000mg/m(3)) and ectopia cordis (1 fetus at 2000mg/m(3); 2 fetuses/1 litter at 10,000mg/m(3)). A second study (G/MTBE-2) evaluated similar exposure levels on GD 5-16 and an additional group exposed to 30,000mg/m(3) from GD 5-10. An increased incidence of cleft palate was observed at 30,000mg/m(3) G/MTBE. No ectopia cordis occurred in the replicate study, but a single observation of gastroschisis was observed at 30,000mg/m(3). The no observed adverse effect levels for maternal/developmental toxicity in the BGVC study were 10,000/2000mg/m(3), 20,000/20,000 for the G/MTBE study, and 10,000/20,000 for the G/MTBE-2 study.


Assuntos
Poluentes Atmosféricos/toxicidade , Desenvolvimento Fetal/efeitos dos fármacos , Gasolina/toxicidade , Animais , Feminino , Inalação , Masculino , Camundongos , Medição de Risco , Testes de Toxicidade
3.
J Vet Pharmacol Ther ; 37(5): 486-99, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24628462

RESUMO

Oral gallium maltolate (GaM) pharmacokinetics (PK) and intestinal tissue (IT) concentrations of elemental gallium ([Ga]) and iron ([Fe]) were investigated in a rabbit model of equine proliferative enteropathy (EPE). New Zealand white does (uninfected controls and EPE-infected, n = 6/group) were given a single oral GaM dose (50 mg/kg). Serial blood samples were collected from 0 to 216 h post-treatment (PT) and IT samples after euthanasia. Serology, qPCR, and immunohistochemistry confirmed, or excluded, EPE. Blood and IT [Ga] and [Fe] were determined using inductively coupled plasma-mass spectrometry. PK parameters were estimated through noncompartmental approaches. For all statistical comparisons on [Ga] and [Fe] α = 5%. The Ga log-linear terminal phase rate constant was lower in EPE rabbits vs. uninfected controls [0.0116 ± 0.004 (SD) vs. 0.0171 ± 0.0028 per hour; P = 0.03]; but half-life (59.4 ± 24.0 vs. 39.4 ± 10.8 h; P = 0.12); Cmax (0.50 ± 0.21 vs. 0.59 ± 0.42 µg/mL; P = 0.45); tmax (1.75 ± 0.41 vs. 0.9 ± 0.37 h; P = 0.20); and oral clearance (6.743 ± 1.887 vs. 7.208 ± 2.565 L/h; P = 0.74) were not. IT's [Ga] and [Fe] were higher (P < 0.0001) in controls. In conclusion, although infection reduces IT [Ga] and [Fe], a 48 h GaM dosing interval is appropriate for multidose studies in EPE rabbits.


Assuntos
Antibacterianos/farmacocinética , Antibacterianos/uso terapêutico , Infecções por Desulfovibrionaceae/microbiologia , Lawsonia (Bactéria) , Compostos Organometálicos/farmacocinética , Compostos Organometálicos/uso terapêutico , Pironas/farmacocinética , Pironas/uso terapêutico , Animais , Infecções por Desulfovibrionaceae/tratamento farmacológico , Feminino , Meia-Vida , Coelhos
4.
J Vet Pharmacol Ther ; 37(6): 571-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24730377

RESUMO

Antimicrobial efficacy against Lawsonia intracellularis is difficult to evaluate in vitro, thus, the effects of gallium maltolate's (GaM) were investigated in a rabbit model for equine proliferative enteropathy (EPE). Juvenile (5-6-week-old) does were infected with 3.0 × 10(8) L. intracellularis/rabbit and allocated into three groups (n = 8). One week postinfection, one group was treated with GaM, 50 mg/kg; one, with doxycycline, 5 mg/kg; and one with a sham-treatment (control). Feces and blood were collected daily and weekly, respectively, to verify presence of L. intracellularis fecal shedding using qPCR, and seroconversion using immunoperoxidase monolayer assay. Rabbits were sacrificed after 1 week of treatment to collect intestinal tissues focusing on EPE-affected sections. Intestinal lesions were confirmed via immunohistochemistry. No difference was noted between treatments regarding EPE-lesions in jejunum (P = 0.51), ileum (P = 0.74), and cecum (P = 0.35), or in L. intracellularis fecal shedding (P = 0.64). GaM and doxycycline appear to have similar efficacy against EPE in infected rabbits.


Assuntos
Antibacterianos/uso terapêutico , Infecções por Desulfovibrionaceae/veterinária , Lawsonia (Bactéria)/efeitos dos fármacos , Compostos Organometálicos/uso terapêutico , Pironas/uso terapêutico , Animais , Infecções por Desulfovibrionaceae/tratamento farmacológico , Infecções por Desulfovibrionaceae/microbiologia , Infecções por Desulfovibrionaceae/patologia , Modelos Animais de Doenças , Feminino , Coelhos , Resultado do Tratamento
5.
Hernia ; 28(2): 537-546, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38261159

RESUMO

PURPOSE: Spigelian hernias arise at the linear semilunaris and account for approximately 1-2% of abdominal hernias. The aetiology is due to a defect of the aponeurosis of the transverse abdominis and when discovered, management is surgical intervention. The aim of this study was to observe operative outcomes for open and minimally invasive repair. METHODS: A retrospective chart review was conducted at two hospitals in Townsville, The Townsville University Hospital and The Mater Private Hospital over a 10-year period (2010 to 2020). A surgical database search (ORMIS & IEMR) was performed at both locations using key search terms, including "spigelian hernia", "laparoscopic", "open". Descriptive statistics were utilised to analyse patient factors and operative outcomes in the public and private setting. RESULTS: 43 cases of Spigelian hernias (25 female, 18 male) were reported over the study period. The average age was 66. There were 36 elective cases and 7 emergency cases. A laparoscopic approach was the preferred method of repair, occurring in 74% of cases. Of these cases, the predominant hernial content was fat only. 65% of cases had a history of prior abdominal surgery unrelated to the "Spigelian belt" location. Complications occurred in 19% of cases. Other variables, such as ethnicity, smoking status, defect size, predisposing factors and recurrence rate, were analysed and did not yield statistical significance. CONCLUSION: Although a small sample size, the data suggest there is no statistically significant difference between operative outcomes, complication rate and predisposing factors between open and minimally invasive case groups.


Assuntos
Hérnia Ventral , Laparoscopia , Adulto , Humanos , Masculino , Feminino , Idoso , Estudos Retrospectivos , Telas Cirúrgicas , Herniorrafia/efeitos adversos , Herniorrafia/métodos , Hérnia Ventral/cirurgia , Abdome/cirurgia , Laparoscopia/efeitos adversos , Laparoscopia/métodos
6.
J Virol ; 84(20): 10671-80, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20686046

RESUMO

A novel assay was developed for Daudi cells in which the antiviral (AV) and antiproliferative (AP) activities of interferon (IFN) can be measured simultaneously. Using this novel assay, conditions allowing IFN AV protection but no growth inhibition were identified and selected. Daudi cells were treated under these conditions, and gene expression microarray analyses were performed. The results of the analysis identified 25 genes associated with IFN-α AV activity. Upregulation of 23 IFN-induced genes was confirmed by using reverse transcription-PCR. Of 25 gene products, 17 were detected by Western blotting at 24 h. Of the 25 genes, 10 have not been previously linked to AV activity of IFN-α. The most upregulated gene was IFIT3 (for IFN-induced protein with tetratricopeptide repeats 3). The results from antibody neutralizing experiments suggested an association of the identified genes with IFN-α AV activity. This association was strengthened by results from IFIT3-small interfering RNA transfection experiments showing decreased expression of IFIT3 and a reduction in the AV activity induced by IFN-α. Overexpression of IFIT3 resulted in a decrease of virus titer. Transcription of AV genes after the treatment of cells with higher concentrations of IFN having an AP effect on Daudi cells suggested pleiotropic functions of identified gene products.


Assuntos
Antivirais/farmacologia , Interferon Tipo I/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Animais , Sequência de Bases , Linhagem Celular , Primers do DNA/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Vírus Elberfeld do Camundongo/efeitos dos fármacos , Vírus Elberfeld do Camundongo/patogenicidade , Análise de Sequência com Séries de Oligonucleotídeos , Interferência de RNA , RNA Interferente Pequeno/genética , Proteínas Recombinantes , Regulação para Cima/efeitos dos fármacos , Vírus da Estomatite Vesicular Indiana/efeitos dos fármacos , Vírus da Estomatite Vesicular Indiana/patogenicidade , Viroses/tratamento farmacológico , Viroses/genética
7.
AJNR Am J Neuroradiol ; 28(2): 226-35, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17296985

RESUMO

BACKGROUND AND PURPOSE: Fractional anisotropy (FA) is a useful measure of connectivity in the brain that can be derived from the diffusion tensor imaging (DTI) dataset. This study investigated the relationship between FA and selected measures of cognition across a broad age group to explore a possible structural basis for cognitive changes with age. METHODS: FA images were generated from DTI data acquired at 1.5T in 87 healthy subjects (age range, 20-73 years). Relationships between a range of cognitive measures and FA were explored using regional and voxel-based analysis. RESULTS: Age and regional average FA were significantly associated in the frontal, parietal, and temporal lobes but not in the occipital lobe. This negative relationship was especially prominent in the prefrontal regions of the frontal lobe, where FA declined at a rate of approximately 3% per decade. Decreased FA in the frontal, temporal, and parietal lobes was associated with poorer cognitive performance in executive maze and in an attention-switching task. A voxel-level analysis of these data revealed that the executive function-FA association was particularly strong and regionally delineated over 2 continuous, bilateral areas extending from the prefrontal cortex to the parietal lobe, with projections to the anterior portions of the thalamus. CONCLUSIONS: We demonstrate a relationship between FA and a measure of executive function-a core cognitive component that is a key feature of cognitive aging. We propose that that FA may provide an early means for the detection of age-related cognitive change and suggest a need for prospective data to explore this association.


Assuntos
Envelhecimento/patologia , Córtex Cerebral/patologia , Cognição , Imagem de Difusão por Ressonância Magnética , Adulto , Idoso , Anisotropia , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Lobo Frontal/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Lobo Occipital/patologia , Lobo Parietal/patologia , Psicometria , Lobo Temporal/patologia
8.
J Clin Neurophysiol ; 24(3): 232-43, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17545826

RESUMO

A study was performed to investigate and compare the relative performance of blind signal separation (BSS) algorithms at separating common types of contamination from EEG. The study develops a novel framework for investigating and comparing the relative performance of BSS algorithms that incorporates a realistic EEG simulation with a known mixture of known signals and an objective performance metric. The key finding is that although BSS is an effective and powerful tool for separating and removing contamination from EEG, the quality of the separation is highly dependant on the type of contamination, the degree of contamination, and the choice of BSS algorithm. BSS appears to be most effective at separating muscle and blink contamination and less effective at saccadic and tracking contamination. For all types of contamination, principal components analysis is a strong performer when the contamination is greater in amplitude than the brain signal whereas other algorithms such as second-order blind inference and Infomax are generally better for specific types of contamination of lower amplitude.


Assuntos
Algoritmos , Artefatos , Encéfalo/fisiologia , Eletroencefalografia , Ruído/efeitos adversos , Estatística como Assunto , Piscadela , Mapeamento Encefálico , Humanos , Movimentos Sacádicos , Processamento de Sinais Assistido por Computador
9.
Drug Alcohol Depend ; 164: 1-7, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27207154

RESUMO

Designer drugs are synthetic structural analogues/congeners of controlled substances with slightly modified chemical structures intended to mimic the pharmacological effects of known drugs of abuse so as to evade drug classification. Benzylpiperazine (BZP), a piperazine derivative, elevates synaptic dopamine and serotonin levels producing stimulatory and hallucinogenic effects, respectively, similar to the well-known drug of abuse, methylenedioxymethamphetamine (MDMA). Furthermore, BZP augments the release of norepinephrine by inhibiting presynaptic autoreceptors, therefore, BZP is a "messy drug" due to its multifaceted regulation of synaptic monoamine neurotransmitters. Initially, pharmaceutical companies used BZP as a therapeutic drug for the treatment of various disease states, but due to its contraindications and abuse potential it was withdrawn from the market. BZP imparts predominately sympathomimetic effects accompanied by serious cardiovascular implications. Addictive properties of BZP include behavioral sensitization, cross sensitization, conditioned place preference and repeated self-administration. Additional testing of piperazine derived drugs is needed due to a scarcity of toxicological data and widely abuse worldwide.


Assuntos
Drogas Desenhadas/farmacologia , Alucinógenos/farmacologia , Piperazinas/farmacologia , Contraindicações , Dopamina/metabolismo , Humanos , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Norepinefrina/metabolismo , Serotonina/metabolismo , Transtornos Relacionados ao Uso de Substâncias/etiologia , Proteínas Vesiculares de Transporte de Monoamina/efeitos dos fármacos
10.
Neurosci Biobehav Rev ; 11(4): 341-52, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3325864

RESUMO

One important function of the catecholamine innervation of the cerebral cortex may be the control of attention. Of particular interest are the catecholamine projections to the cerebral cortex from the reticular formation, namely the dopamine neurons of the ventral tegmentum of the midbrain and the noradrenergic neurons of the locus coeruleus in the upper pons. Animal studies implicate noradrenaline and dopamine in a wide range of attention-related behaviours involving search and exploratory activity, distractibility, response rate, discriminability and the switching of attention. Most human studies come from the clinical literature relating to schizophrenia, Parkinson's disease and attention deficit disorder. An association has been claimed in each of these conditions between abnormal catecholamine activity (in particular dopamine) and attentional dysfunction. In particular, difficulty with the attachment of appropriate responses to environmental stimuli, akin to those observed in animals with lesions to central dopamine pathways, indicates a role for dopamine in response selection processes. Overall, the animal and human studies reviewed indicate a role for central noradrenaline and dopamine in the early and late processing of information, respectively.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Dopamina/fisiologia , Norepinefrina/fisiologia , Animais , Transtorno do Deficit de Atenção com Hiperatividade/metabolismo , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Encéfalo/metabolismo , Encefalopatias/metabolismo , Encefalopatias/fisiopatologia , Dopamina/metabolismo , Humanos , Norepinefrina/metabolismo , Primatas , Ratos , Formação Reticular/fisiologia
11.
Neurosci Biobehav Rev ; 11(4): 353-64, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3325865

RESUMO

Part I of this review [17] found evidence from animal and clinical studies of a role for catecholamines in the control of attention. This part of the review examines the results of a systematic study of the acute effects of a number of catecholamine active drugs on measures of attention in normal adults. The results are interpreted within the context of a general capacity model of information processing in which level of arousal determines the capacity to process stimulus information and level of activation the capacity for processing response demands. Whilst the dopamine antagonist, droperidol, and the alpha agonist, clonidine, had similar effects on behavioural indices of processing capacity and reports of the degree of effort required to carry out processing, they differentially affected subjective state and measures of activation and arousal. These differences provide some support for the hypothesis that central noradrenaline and dopamine modulate the capacity for early and late processing of information, respectively, in humans.


Assuntos
Atenção/fisiologia , Catecolaminas/fisiologia , Clonidina/administração & dosagem , Droperidol/administração & dosagem , Metilfenidato/administração & dosagem , Adolescente , Adulto , Catecolaminas/metabolismo , Relação Dose-Resposta a Droga , Humanos , Masculino
12.
Biol Psychiatry ; 34(5): 311-20, 1993 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-8399831

RESUMO

This study investigated event-related potential (ERP) indices of information processing in sufferers of posttraumatic stress disorder (PTSD). ERPs were obtained from 18 PTSD patients and 20 controls while they performed a target discrimination task requiring the detection of infrequent target tones from a background sequence of frequent and infrequent distractor tones. A delayed N2 and an attenuated P3 that failed to differentiate target from distractor tones indicated that patients had abnormal difficulty distinguishing task stimuli of differing relevance. It is proposed that this difficulty is reflected behaviorally in the slowed reaction time by patients to target stimuli and may underlie the disturbed concentration and memory impairments found in PTSD. It may also be related to dysfunction in central noradrenaline function, which has been shown to be both crucial in selective attention and abnormal in PTSD.


Assuntos
Nível de Alerta/fisiologia , Atenção/fisiologia , Eletroencefalografia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Tonsila do Cerebelo/fisiopatologia , Córtex Cerebral/fisiopatologia , Feminino , Humanos , Locus Cerúleo/fisiopatologia , Masculino , Vias Neurais/fisiopatologia , Norepinefrina/fisiologia , Córtex Pré-Frontal/fisiopatologia , Tempo de Reação/fisiologia , Transtornos de Estresse Pós-Traumáticos/psicologia
13.
Biol Psychiatry ; 39(10): 845-56, 1996 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-9172705

RESUMO

This study investigated event-related potential (ERP) indices of information processing in sufferers of panic disorder (PD). ERPs were recorded from 14 PD patients and 15 controls during an auditory target detection task. The task required subjects to discriminate infrequent target tones (p = .14; 2000 Hz) from frequent (p = .72; 1000 Hz) and infrequent (p = .14; 500 Hz) distractor tones. A frontal P300 (P3a) identified in the PD group was characteristic of activity that would be expected to novel, task-irrelevant stimuli and is consistent with junctional pathology involving the prefrontal-limbic pathways. This study provides psychophysiological evidence of an abnormality in PD of the brain's processing of physical changes in the stimulus field that occurs even under conditions of low stimulus load. It may assist in helping to understand the breakdown in information processing that occurs in PD under high load conditions such as crowds and supermarkets.


Assuntos
Potenciais Evocados Auditivos , Transtorno de Pânico/diagnóstico , Adulto , Transtornos de Ansiedade/psicologia , Atenção , Feminino , Humanos , Sistema Límbico/fisiopatologia , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/fisiopatologia , Tempo de Reação
14.
Neuropsychologia ; 29(9): 889-905, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1944884

RESUMO

An index-middle finger (double) tapping task was used to examine hemispheric differences in the planning and execution of skilled finger movements. In two experiments, subjects responded to a simple cue presented tachistoscopically in the left or right visual field, by performing a predetermined number of double taps, (between one and eight inclusive), with either the left or right hand. Reaction times (RT) increased linearly as a function of increasing number of taps, when response sequences were controlled by the left hemisphere. In contrast, an inverse quadratic trend was obtained with right hemisphere control. When both hemispheres were involved in the stimulus-response sequence, the latency function incorporated elements of both trends, suggesting interaction between the hemispheres. The RT trends reflect differences in motor planning between the hemispheres. The conditions engaging only the right or left hemispheres did not differ in motor execution, as measured by tapping duration, variability or errors. However, when both hemispheres were involved there was evidence of interaction, which was evident as interference when the right visual field or left hemisphere was cued but the motor response was under the control of the right hemisphere (left hand). Overall, the results indicate that hand differences in fine motor skill may be determined by hemispheric differences associated with motor preparation rather than response execution.


Assuntos
Lateralidade Funcional , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Análise de Variância , Dedos/fisiologia , Humanos , Masculino , Tempo de Reação , Campos Visuais/fisiologia
15.
Neuropsychologia ; 27(2): 131-9, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2538773

RESUMO

The role of brain catecholamines in covert orienting was tested in normal subjects using a cued reaction time paradigm which measures the directional engagement, disengagement and movement of attention. Droperidol and clonidine were administered intravenously to suppress central dopamine and noradrenaline transmission. Both drugs produced reductions in the cost of invalid cueing without change in the benefit of valid cueing suggesting that both noradrenaline and dopamine are involved in facilitating the disengagement of attention. These results are relevant to the slowed disengagement observed with parietal lesions in monkeys and humans since this region of the cortex associated with visuospatial analysis receives a dense innervation by both dopamine and noradrenaline projections in primates.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Catecolaminas/fisiologia , Orientação/fisiologia , Adolescente , Adulto , Nível de Alerta/fisiologia , Dopamina/fisiologia , Humanos , Masculino , Norepinefrina/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Receptores Adrenérgicos/fisiologia , Receptores Dopaminérgicos/fisiologia
16.
Neuropsychologia ; 30(2): 123-32, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1560891

RESUMO

The ability to orient visual attention covertly was studied in 11 patients who had suffered a moderate or severe closed head injury (CHI) at least 1 year previously. Their performance was compared to nine matched controls using a cued reaction time (RT) task which measured the RT benefit of valid directional cueing and the RT cost of miscueing. The CHI and control groups did not differ in overall RT. Relative to controls, the CHI group showed normal cost but hardly any benefit, indicating that the normal capacity to pre-align attention with a cued location was impaired.


Assuntos
Atenção/fisiologia , Traumatismos Cranianos Fechados/fisiopatologia , Orientação/fisiologia , Adulto , Análise de Variância , Sinais (Psicologia) , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia , Percepção Visual/fisiologia
17.
J Immunol Methods ; 192(1-2): 133-6, 1996 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-8699009

RESUMO

An improved method is described for the detection of Escherichia coli by an enzyme linked immunofilter assay (ELIFA) using nitrocellulose membrane sandwiched between two 96-well plates. The incorporation of a pumping system permits a continuous flow of reagents and/or wash fluids through the membrane and provides an assay procedure capable of detecting 10(3) bacteria per well within 40 min. Quantitative bacterial detection was based on precipitated chromogen determined by scanning densitometry. The procedure represents a significant improvement in assay time and/or sensitivity over previously described ELIFA and ELISA methods for whole bacterial cells.


Assuntos
Escherichia coli/isolamento & purificação , Técnicas Imunoenzimáticas , Escherichia coli/imunologia , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/imunologia , Filtração/métodos , Técnicas Imunoenzimáticas/instrumentação , Sensibilidade e Especificidade
18.
J Immunol Methods ; 141(2): 253-61, 1991 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-1880430

RESUMO

The purpose of this study was to compare and contrast two enzyme immunoassay systems: the enzyme-linked immunosorbent assay (ELISA), which utilizes polystyrene microtiter plates as the adsorptive surface and the enzyme-linked immunoflow assay (ELIFA), which utilizes nitrocellulose membranes. The principal parameter under scrutiny was the denaturing or unfolding effects caused by the interaction of the protein with the adsorptive surfaces in each assay system. These effects were monitored by utilizing two conformationally distinct forms of human C-reactive protein (CRP), the native form of CRP and a denatured form (M-CRP), with a corresponding panel of monoclonal antibodies (MAbs) specific to either CRP or M-CRP. The results show that the ELIFA system was less sensitive than the ELISA system but that the ELIFA assay can be completed in less time than the ELISA. Also, adsorption of native CRP to the polystyrene surface in the ELISA system resulted in conformational changes of the adsorbed native CRP protein such that M-CRP reactive determinants were available for binding with anti-M-CRP MAbs, whereas native CRP adsorbed to the nitrocellulose membrane in the ELIFA system resulted in very limited conversion of CRP to M-CRP reactive epitopes. These results have important implications for development of immunoassays and screening of MAbs for proteins whose conformations may be affected by adsorption to various surfaces.


Assuntos
Anticorpos Monoclonais , Proteína C-Reativa/análise , Ensaio de Imunoadsorção Enzimática , Proteína C-Reativa/imunologia , Cálcio/farmacologia , Colódio , Humanos , Poliestirenos , Conformação Proteica , Desnaturação Proteica
19.
J Med Chem ; 30(7): 1214-8, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3599027

RESUMO

A group of amides and amines related to 4-amino-N-(1-phenylethyl)benzamide, 1, were prepared in a study on the relationship of structure to anticonvulsant activity in this compound. Acylation and alkylation of the amino group of 1 resulted in almost total loss of anticonvulsant activity. Insertion of a methylene between the 4-amino group and the aromatic ring of 1 produced a slight increase in anticonvulsant potency and a significant increase in toxicity. Hydride reduction of the amide carbonyl in 1 also yielded compounds having a slightly lower ED50 against convulsions induced by electroshock and a much lower TD50 in the rotorod assay. Modification of the 1-phenylethyl group of 1 also decreased anticonvulsant potency.


Assuntos
Anticonvulsivantes/síntese química , Benzamidas/síntese química , Animais , Anticonvulsivantes/farmacologia , Anticonvulsivantes/toxicidade , Benzamidas/farmacologia , Masculino , Camundongos , Relação Estrutura-Atividade
20.
J Med Chem ; 30(4): 729-32, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3560164

RESUMO

CCK-30-33 has been identified as the minimum fragment of CCK with nanomolar affinity for the central CCK receptors, as assayed by displacement of [3H]-Boc-beta-alanyl-CCK-30-33 (pentagastrin) in homogenized mouse cerebral cortex. Examination of binding using this assay in the two series Boc-Trp-X-Phe-NH2 when X = Met-Asp (Boc-CCK-30-33), Gly-Asp, Met-Gly, and Gly-Gly and when X = (CH2)n (n = 0-4) reveals that modification of the tetrapeptide reduces affinity to a maximum of micromolar affinity (Boc-Trp-Gly-Asp-Phe-NH2; Ki = 2 X 10(-6) M), whereas in the series when n = 0 and 2 pentamolar affinity is still retained (Boc-Trp-Phe-NH2, Ki = 7 X 10(-5) M; Boc-Trp NH CH2-CH2-CO-Phe-NH2, Ki = 3 X 10(-5) M). Modification of the tetrapeptide CCK-30-33 reduces affinity 1000-fold, whereas di- and tripeptide fragments are identified that reduce affinity only a further 10-fold. This structure-activity relationship establishes a basis to design "peptoid" analogues of CCK that have therapeutic potential.


Assuntos
Córtex Cerebral/análise , Gastrinas/metabolismo , Receptores da Colecistocinina/metabolismo , Tetragastrina/metabolismo , Sequência de Aminoácidos , Animais , Camundongos , Peptoides , Ligação Proteica , Relação Estrutura-Atividade , Tetragastrina/síntese química
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa