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The iron-based high temperature superconductors exhibit a rich phase diagram reflecting a complex interplay between spin, lattice, and orbital degrees of freedom. The nematic state observed in these compounds epitomizes this complexity, by entangling a real-space anisotropy in the spin fluctuation spectrum with ferro-orbital order and an orthorhombic lattice distortion. A subtle and less-explored facet of the interplay between these degrees of freedom arises from the sizable spin-orbit coupling present in these systems, which translates anisotropies in real space into anisotropies in spin space. We present nuclear magnetic resonance studies, which reveal that the magnetic fluctuation spectrum in the paramagnetic phase of BaFe2As2 acquires an anisotropic response in spin-space upon application of a tetragonal symmetry-breaking strain field. Our results unveil an internal spin structure of the nematic order parameter, indicating that electronic nematic materials may offer a route to magneto-mechanical control.
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We present the design and construction of an NMR probe to investigate single crystals under strain at cryogenic temperatures. The probe head incorporates a piezoelectric-based apparatus from Razorbill Instruments that enables both compressive and tensile strain tuning up to strain values on the order of 0.3% with a precision of 0.001%. 75As NMR in BaFe2As2 reveals large changes to the electric field gradient and indicates that the strain is homogeneous to within 16% over the volume of the NMR coil.
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High dry friction requires intimate contact between two surfaces and is generally obtained using soft materials with an elastic modulus less than 10 MPa. We demonstrate that high-friction properties similar to rubberlike materials can also be obtained using microfiber arrays constructed from a stiff thermoplastic (polypropylene, 1 GPa). The fiber arrays have a smaller true area of contact than a rubberlike material, but polypropylene's higher interfacial shear strength provides an effective friction coefficient of greater than 5 at normal loads of 8 kPa. At the pressures tested, the fiber arrays showed more than an order of magnitude increase in shear resistance compared to the bulk material. Unlike softer materials, vertical fiber arrays of stiff polymer demonstrate no measurable adhesion on smooth surfaces due to high tensile stiffness.
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ABSTRACT Fusarium ear rot and fumonisin contamination are serious problems for maize growers, particularly in the southeastern United States. The lack of maize genotypes highly resistant to infection by Fusarium verticillioides or to fumonisin contamination emphasizes the need for management strategies to prevent contamination by this mycotoxin. Information on the initial appearance of infection and fumonisin contamination of kernels and their increase over time is needed to determine if early harvest may be an appropriate control strategy. Maize ears from replicated studies at two locations in eastern North Carolina were harvested weekly, starting 2 weeks after pollination and continuing for 14 weeks. The percentage of kernels infected with F. verticillioides and the fumonisin contamination in the harvested samples were determined. Kernel infection by F. verticillioides and fumonisin contamination appeared as kernels neared physiological maturity and increased up to the average harvest date for maize in North Carolina. Beyond this date, the concentrations of fumonisin fluctuated. Under years conducive for fumonisin contamination, early harvest (greater than 25% grain moisture) may help reduce the level of contamination.
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We estimate the set dimension and find bounds for the set entropy of a cellular automaton model for single lane traffic. Set dimension and set entropy, which are measures of the information content per cell, are related to the fractal nature of the automaton [S. Wolfram, Physica D 10, 1 (1989); Theory and Application of Cellular Automata, edited by S. Wolfram (World Scientific, Philadelphia, 1986)] and have practical implications for data compression. For models with maximum speed v(max), the set dimension is approximately log((v(max)+2))2.5, which is close to one bit per cell regardless of the maximum speed. For a typical maximum speed of five cells per time step, the dimension is approximately 0.47.
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1. Inhibition of p38 MAP kinase has been investigated extensively as a potential therapy for cytokine-mediated diseases such as autoimmune and inflammatory diseases. SB-242235 (1-(4-piperidinyl)-4-(4-fluorophenyl)-5-(2-methoxy-4-pyrimidinyl) imidazole) is a potent and selective p38 MAP kinase inhibitor; the preclinical pharmacokinetics of SB-242235 have been described previously. The present studies were conducted to describe the in vitro metabolic rates and routes of SB-242235 metabolism, to characterize its in vivo preclinical metabolism, and to use these data to aid in the prediction of the pharmacokinetic behaviour of SB-242235 in man. 2. SB-242235 was metabolically stable in rat, dog, monkey and human hepatic microsomes, isolated hepatocytes and liver slices in vitro. The in vivo preclinical metabolism studies were consistent with the in vitro findings; SB-242235 was minimally metabolized, and was primarily excreted unchanged in the urine (45 and 67% of the administered dose in the rat and monkey, respectively). 3. Allometric scaling using various correction factors predicted that SB-242235 would have low clearance in man with a predicted half-life ranging from 11.5 to 18.7h. This prediction was consistent with the observed mean half-life of 16.4h in the first-in-man study for SB-242235. An allometric scaling method with a correction for interspecies differences in glomerular filtration rate provided the most accurate prediction of the pharmacokinetic behaviour of SB-242235 in humans, although the clinical data also highlight potential difficulties in conducting prospective allometry.
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Inibidores Enzimáticos/farmacocinética , Imidazóis/farmacocinética , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Piridinas/farmacocinética , Animais , Bile/metabolismo , Biotransformação , Cromatografia Líquida de Alta Pressão , Cães , Fezes/química , Humanos , Macaca fascicularis , Masculino , Espectrometria de Massas , Microssomos Hepáticos/metabolismo , Ratos , Especificidade da Espécie , Proteínas Quinases p38 Ativadas por MitógenoRESUMO
We examined whether exposure to polychlorinated biphenyls (PCBs) around puberty would produce hyperactivity and impulsiveness in adult Sprague-Dawley rats. Randomly assigned groups consumed food containing environmental concentrations of Aroclor 1248, PCB-contaminated St. Lawrence River carp, or corn oil (control). All received operant training to a final multiple (mult) 120-s, fixed interval (FI), 5-min extinction (EXT) schedule. Pressing rates of both exposed groups for drops of water averaged more than 1.5 times that of controls, especially toward the end of the 120-s interval. This overactivity included bursts with short (< or =0.5 s) interresponse times (IRTs), behavior characteristic of hyperactive boys and genetically hyperactive rats. The exposed groups also overreacted to the decreases in reinforcement density associated with transition to the final schedule. The results were interpreted in terms of the possible alterations in the animals' reinforcement mechanisms and the possible neurotoxic effects of PCB exposure.
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Arocloros/toxicidade , Carpas , Contaminação de Alimentos , Comportamento Impulsivo/induzido quimicamente , Atividade Motora/efeitos dos fármacos , Bifenilos Policlorados/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Atenção/efeitos dos fármacos , Condicionamento Operante/efeitos dos fármacos , Masculino , New York , Ratos , Ratos Sprague-Dawley , Esquema de ReforçoRESUMO
A study was conducted to assess the extent to which the consumption of local fish contaminated with p,p'-dichlorodiphenyl dichloroethylene (p,p'-DDE), mirex, and hexachlorobenzene (HCB) has impacted the concentrations of these compounds in the milk of nursing Mohawk women residing along the St. Lawrence River. From 1986 to 1992, 97 Mohawk women were interviewed, and each donated a one-time sample of at least 50 ml of breast milk. The comparison population consisted of 154 Caucasians from other rural areas in New York State. After adjustment for potential confounders, Mohawk mothers who gave birth from 1986 to 1990 had significantly higher geometric mean p,p'-DDE milk concentrations than did the control group, but no significant differences were observed from 1991 to 1992. In contrast, mirex was significantly elevated among the Mohawks throughout the study period, while HCB showed no difference at any point. Mohawk women with the greatest estimated cumulative lifetime exposure to p,p'-DDE from local fish consumption had a significantly higher geometric mean milk level of that compound relative to control women, but no differences in mirex or HCB concentrations in breast milk by local fish consumption were found. The reduction in breast milk p,p'-DDE concentrations among the Mohawk women from 1986 to 1990 parallels a corresponding decrease in local fish consumption, and may be the result of the advisories that have been issued over the past decade recommending against the consumption of local fish by pregnant and nursing Mohawk women. Elevations in the concentrations of mirex in the breast milk of the Mohawks are consistent with the fact that it is a common contaminant in the region and throughout the Lake Ontario-St. Lawrence River Basin.
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Diclorodifenil Dicloroetileno/farmacocinética , Contaminação de Alimentos , Fungicidas Industriais/farmacocinética , Hexaclorobenzeno/farmacocinética , Inseticidas/farmacocinética , Leite Humano/química , Mirex/farmacocinética , Alimentos Marinhos , Adulto , Animais , Diclorodifenil Dicloroetileno/análise , Dieta , Exposição Ambiental , Feminino , Peixes , Fungicidas Industriais/análise , Hexaclorobenzeno/análise , Humanos , Inseticidas/análise , Mirex/análise , New York/epidemiologiaRESUMO
This study examined the association of contaminated fish consumption and polychlorinated biphenyl (PCB) body burden by comparing the similarity of the congener pattern in yellow perch, caught near the point source of industrial pollution, and in other local fish to the pattern found in the breast milk of Mohawk women from Akwesasne, a Native American community located along the St. Lawrence River in New York, Ontario, and Quebec. The similarity is defined by the weighted Euclidean distance between two congener patterns. Ninety-seven Mohawk mothers participated and provided samples of breast milk. One hundred fifty-four nursing women from the Supplemental Nutrition Program for Women, Infants and Children (WIC) of Warren and Schoharie counties, New York, who gave birth during the same time period, were used as the comparison group. Results revealed that the breast milk of the Mohawk women, who ate the most local fish, had a congener pattern that more closely resembled that of perch caught near the waste site or average sampled fish caught in the Reserve than Mohawk women who ate less fish or the controls. The outcome demonstrates how PCBs may be "fingerprinted" as they migrate offsite from industrial sources and ultimately result in human exposure.
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Peixes , Contaminação de Alimentos , Indígenas Norte-Americanos/estatística & dados numéricos , Exposição Materna/estatística & dados numéricos , Leite Humano/química , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise , Animais , Estudos de Casos e Controles , Ingestão de Alimentos , Feminino , Humanos , New York/epidemiologia , Ontário/epidemiologia , GravidezRESUMO
Irrigated pastures are significant contributors of phosphorus (P) to inland watercourses, with much of the P coming from applied fertilizer. It was hypothesized that the timing of P fertilizer application relative to irrigation regulates P concentrations in runoff and infiltrating water. To test this hypothesis, a two-by-two factorial experiment was conducted on twelve 8- x 30-m border-irrigated bays growing perennial pasture. Phosphorus fertilizer in the form of single superphosphate (44 kg P ha(-1)) was surface-broadcast onto the bays when the nominal change in soil water deficit reached 0 or 50 mm (U.S. Class A pan evaporation minus rainfall). Following fertilizer application, the bays were again irrigated when the nominal soil water deficit between fertilizing and the subsequent irrigation reached either 0 or 50 mm. The volume of water applied, runoff volume, and changes in soil water content were recorded for the three irrigations following fertilizer application. Total phosphorus (TP) and filtrable reactive phosphorus (FRP, <0.45 microm) concentrations in runoff and at depths of 0.1, 0.3, and 0.6 m in the soil were also measured. Soil water content at fertilizer application had less effect on P concentrations in runoff and soil water than the additional time between fertilizing and irrigating. By allowing a deficit of 50 mm between fertilizer application and irrigation, the average concentration of P in runoff and moving below a soil depth of 0.1 m was approximately halved. To maximize fertilizer use efficiency and minimize environmental effects, a delay should occur between applying P fertilizer and irrigating perennial pasture.
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Fertilizantes , Fósforo/análise , Poluentes da Água/análise , Agricultura/métodos , Fatores de Tempo , Movimentos da Água , Poluição da Água/prevenção & controleAssuntos
Fígado/patologia , Sarcoidose/diagnóstico , Redução de Peso , Fosfatase Alcalina/sangue , Anorexia/etiologia , Paralisia de Bell/diagnóstico , Paralisia de Bell/etiologia , Biópsia por Agulha , Diabetes Mellitus Tipo 2/complicações , Diagnóstico Diferencial , Feminino , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/isolamento & purificação , Anticorpos Anti-Hepatite A , Anticorpos Anti-Hepatite/sangue , Humanos , Hipertensão/complicações , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Órbita/patologia , Antro Pilórico/patologia , Sarcoidose/complicações , Transaminases/sangueRESUMO
OBJECTIVE: To examine the relationship of premorbid variables, injury severity, and cognitive and functional status to outcome 1 year after traumatic brain injury (TBI) and to assess the feasibility of multivariate path analysis as a way to discover those relationships. DESIGN: Prospective, longitudinal. SETTINGS: Level I trauma center, acute inpatient rehabilitation hospital. PATIENTS: One hundred seven subjects (87 men, 20 women; mean age, 33.91 +/- 14.2 yr) who had experienced severe TBI, typically from motor vehicle crashes. INTERVENTIONS: Acute medical and rehabilitation care. MAIN OUTCOME MEASURES: Disability Rating Scale, Community Integration Questionnaire, and return to employment. Evaluated in acute rehabilitation, and at 6 and 12 months' postinjury. RESULTS: Path analyses revealed that premorbid factors had significant relationships with injury severity, functional skills, cognitive status, and outcome; injury severity affected cognitive and functional skills; and cognitive status influenced outcome. No significant relationships were found between injury severity and emotional status, injury severity and outcome, emotional status and outcome, and functional skills and outcome. CONCLUSIONS: Multivariate analysis is important to understanding outcome after TBI. Injury severity, as measured in this study, is less important to 12-month outcome than the premorbid status of the person and the difficulties (particularly cognitive deficits) exhibited at follow-up 6 months after the trauma.
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Lesões Encefálicas/diagnóstico , Lesões Encefálicas/reabilitação , Adulto , Feminino , Humanos , Masculino , Modelos Teóricos , Análise Multivariada , Prognóstico , Estudos Prospectivos , Fatores de Risco , Índices de Gravidade do Trauma , Resultado do TratamentoRESUMO
OBJECTIVE: To correlate serum glycolic acid levels with clinical severity and outcome in ethylene glycol poisoning and to determine if glycolic acid levels are predictive of renal failure and the need for hemodialysis. METHODS: We measured serum ethylene glycol and glycolic acid levels by gas chromatography/mass spectrometry for 41 admissions (39 patients) for ethylene glycol ingestion and performed retrospective chart reviews. RESULTS: Eight patients died, all of whom developed acute renal failure. Of the survivors, 15 also developed acute renal failure, whereas 18 did not. Of those with normal renal function, 8 had glycolic acid levels below detection limits (< 0.13 mmol/L) despite ethylene glycol levels as high as 710 mg/dL; 7 of these patients coingested ethanol. Pertinent initial laboratory data for each group are as follows (mean; range): Deceased: pH 6.99 (6.82-7.22); bicarbonate, 4.8 mmol/L (2-9); anion gap, 28.6 mmol/L (24-40); glycolic acid, 23.5 mmol/L (13.8-38.0); ethylene glycol, 136.5 mg/dL (6-272). Survived/acute renal failure: pH 7.07 (6.75-7.32); bicarbonate, 5.6 mmol/L (1-12); anion gap, 28.7 mmol/L (18-41); glycolic acid, 20.2 mmol/L (10.0-30.0); ethylene glycol, 238.8 mg/dL (12-810). No acute renal failure with glycolic acid > 1.0 mmol/L: pH 7.29 (7.12-7.46); bicarbonate, 14.7 mmol/L (4-23); anion gap, 16.5 mmol/L (10-26); glycolic acid, 6.8 mmol/L (2.6-17.0); ethylene glycol, 269.1 mg/dL (6-675). No acute renal failure with glycolic acid < 1.0 mmol/L: pH 7.41 (7.38-7.47); bicarbonate, 23.4 mmol/L (17-25); anion gap, 11.8 mmol/L (8-18); glycolic acid, 0.1 mmol/L (0-0.66); ethylene glycol, 211 mg/dL (8-710). The mean time postingestion to admission generally correlated with severity as follows: deceased, > or = 10.4 h; survived/acute renal failure, > or = 9.9 h; no acute renal failure with glycolic acid > 1.0 mmol/L, > or = 6.2 h; no acute renal failure with glycolic acid < 1.0 mmol/L, > or = 3.7 h. Hematuria was more prevalent than oxaluria (86% and 41%, respectively), but neither was individually predictive of acute renal failure. Good correlations were found between glycolic acid levels and anion gap (r2 = 0.7724), pH (r2 = 0.7921), and bicarbonate (r2 = 0.6579); poor correlations (r2 < 0.0023) occurred between ethylene glycol levels and glycolic acid, pH, anion gap, and bicarbonate. Measured ethylene glycol values were highly correlated with ethylene glycol values calculated from the osmolal gap (r2 = 0.9339), but the latter overestimates the true value by about 7%, on average. An initial glycolic acid level > or = 10 mmol/L predicts acute renal failure with a sensitivity of 100%, a specificity of 94.4%, and an efficiency of 97.6%. Ethylene glycol levels are not predictive of acute renal failure or central nervous system manifestations of toxicity. If only ethylene glycol values are available (measured or calculated), an initial anion gap > 20 mmol/L is 95.6% sensitive and 94.4% specific for acute renal failure when ethylene glycol is present. Likewise, initial pH < 7.30 is 100% sensitive and 88.5% specific for acute renal failure. CONCLUSION: We propose glycolic acid > 8 mmol/L as a criterion for the initiation of hemodialysis in ethylene glycol ingestion. Patients with glycolic acid < 8 mmol/L probably do not need dialysis, regardless of the ethylene glycol concentration, when metabolism of ethylene glycol is therapeutically inhibited. In the absence of glycolic acid values, an anion gap > 20 mmol/L or pH < 7.30 predicts acute renal failure.
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Etilenoglicol/intoxicação , Glicolatos/sangue , Intoxicação/sangue , Intoxicação/terapia , Diálise Renal , Bicarbonatos/sangue , Biomarcadores , Doenças do Sistema Nervoso Central/induzido quimicamente , Doenças do Sistema Nervoso Central/patologia , Etilenoglicol/sangue , Cromatografia Gasosa-Espectrometria de Massas , Hematúria/metabolismo , Homicídio , Humanos , Concentração de Íons de Hidrogênio , Hiperoxalúria/metabolismo , Testes de Função Renal , Concentração Osmolar , Estudos Retrospectivos , Suicídio , Tentativa de Suicídio , Resultado do TratamentoRESUMO
Traumatic aortic rupture is a significant cause of fatalities in frontal automobile crashes. However, such ruptures are difficult to reproduce experimentally in cadaveric surrogates, and it is difficult to observe dynamic aortic response in situ. So, the aortic injury mechanism or mechanisms remains in dispute. This study is a staged investigation of the physical parameters and mechanisms of human aortic rupture. The investigation includes both experimental study of local and global viscoelastic properties and failure properties of aortas using aortic tissue samples, excised aortas in vitro, and whole human aortas in situ in cadaver thoraxes. This study is the first phase in a staged programme to develop a finite element computer model of aorta injury to examine the mechanisms of aorta injury in automobile crashes. The high-rate local biaxial properties of porcine aorta tissue are determined from samples taken from the isthmus region, the most common area of failure in traumatic aorta injury. Using porcine aortas, similar in structure and physical characteristics to human aortic tissue, biaxial oscillatory response is determined at large strains and high strain rates. From this data, a hyperelastic material model with a failure threshold is developed that is in good agreement with local property data determined from oscillatory tests at 20 Hz and 65 Hz. Further, whole aorta tests are performed using pressure application with aortic pressure time histories similar in onset rate to those seen in cadaveric sled testing. These tests establish the ultimate stretch ratio and strain to failure for human aorta specimens. The specimens show no significant difference in response between the in situ tests and the in vitro tests. This indicates either that the internal thoracic boundary conditions may not be important in the stress and strain level of aorta failure or that the number of in situ tests (3) was too small to establish a difference. A Weibull survival analysis of the whole aorta failure tests shows significant dependence of aortic ultimate stretch ratio on age. A 50% risk of failure is 852 kPa in the circumferential direction and 426 kPa in the longitudinal direction. For pressure, the 50% risk of failure for all the tests is approximately 101 kPa. This increases to greater than 120 kPa for subjects below 68 years.
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Outcome studies examining recovery from traumatic brain injury (TBI) often fail to provide a clear understanding of the time course of cognitive, emotional, and behavioural recovery. The present study represents an effort to prospectively study individuals with TBI at fixed intervals, specifically 6 and 12 months post-injury with a window of +/- 1 month. Seventy-two individuals with new-onset TBI underwent neuropsychological evaluation and clinical interview at 6 and 12 months post-injury. Results revealed significant improvements in cognitive abilities, including memory, processing speed, language abilities, and constructional skills. There were significant gains in community integration and involvement in productive activities, but limitations in driving activities remained. Although individuals with mild-moderate TBI performed better than individuals with severe TBI, both groups demonstrated equivalent rates of recovery across domains. The results of this study provide important information regarding the time course of TBI recovery.
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Lesões Encefálicas/reabilitação , Cognição , Emoções , Ajustamento Social , Atividades Cotidianas , Adolescente , Adulto , Idoso , Análise de Variância , Condução de Veículo , Lesões Encefálicas/fisiopatologia , Lesões Encefálicas/psicologia , Feminino , Seguimentos , Escala de Coma de Glasgow , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos Prospectivos , Recuperação de Função Fisiológica , Fatores de TempoRESUMO
The pharmacological and pharmacokinetic profile of SB-222200 [(S)-(-)-N-(alpha-ethylbenzyl)-3-methyl-2-phenylquinoline-4-car boxami de], a human NK-3 receptor (hNK-3R) antagonist, was determined. SB-222200 inhibited (125)I-[MePhe(7)]neurokinin B (NKB) binding to Chinese hamster ovary (CHO) cell membranes stably expressing the hNK-3 receptor (CHO-hNK-3R) with a K(i) = 4.4 nM and antagonized NKB-induced Ca(2+) mobilization in HEK 293 cells stably expressing the hNK-3 receptor (HEK 293-hNK-3R) with an IC(50) = 18.4 nM. SB-222200 was selective for hNK-3 receptors compared with hNK-1 (K(i) > 100,000 nM) and hNK-2 receptors (K(i) = 250 nM). In HEK 293 cells transiently expressing murine NK-3 receptors (HEK 293-mNK-3R), SB-222200 inhibited binding of (125)I-[MePhe(7)]NKB (K(i) = 174 nM) and antagonized NKB (1 nM)-induced calcium mobilization (IC(50) = 265 nM). In mice oral administration of SB-222200 produced dose-dependent inhibition of behavioral responses induced by i.p. or intracerebral ventricular administration of the NK-3 receptor-selective agonist, senktide, with ED(50) values of approximately 5 mg/kg. SB-222200 effectively crossed the blood-brain barrier in the mouse and rat. The inhibitory effect of SB-222200 against senktide-induced behavioral responses in the mouse correlated significantly with brain, but not plasma, concentrations of the compound. Pharmacokinetic evaluation of SB-222200 in rat after oral administration (8 mg/kg) indicated sustained plasma concentrations (C(max) = about 400 ng/ml) and bioavailability of 46%. The preclinical profile of SB-222200, demonstrating high affinity, selectivity, reversibility, oral activity, and central nervous system penetration, suggests that it will be a useful tool compound to define the physiological and pathophysiological roles of NK-3 receptors, in particular in the central nervous system.
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Encéfalo/efeitos dos fármacos , Quinolinas/farmacologia , Receptores da Neurocinina-3/antagonistas & inibidores , Animais , Encéfalo/metabolismo , Células CHO , Cálcio/metabolismo , Cricetinae , Relação Dose-Resposta a Droga , Humanos , Técnicas In Vitro , Iris/efeitos dos fármacos , Iris/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fragmentos de Peptídeos/farmacologia , Quinolinas/farmacocinética , Coelhos , Ratos , Ratos Sprague-Dawley , Substância P/análogos & derivados , Substância P/farmacologiaRESUMO
OBJECTIVE: To establish the validity of the Orientation Log (O-Log) by comparison with the Galveston Orientation and Amnesia Test (GOAT). DESIGN: Correlation of daily measures of orientation. SETTING: Acute rehabilitation hospital. SUBJECTS: Sixty-eight inpatients receiving rehabilitation following traumatic brain injury (TBI). PRIMARY MEASURES: The O-Log and GOAT. RESULTS: There was a significant correlation between the GOAT and O-Log (r = .901, P<.001). A cutoff of 25 on the O-Log was found to be comparable with the 75 cutoff on the GOAT. The scales were equivalent in measuring duration of posttraumatic amnesia. CONCLUSIONS: The O-Log is a valid measure of orientation for people with TBI and offers some advantages in administration over the GOAT.
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Lesões Encefálicas/psicologia , Orientação , Escalas de Graduação Psiquiátrica/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Lesões Encefálicas/reabilitação , Feminino , Humanos , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Psicometria , Padrões de Referência , Reprodutibilidade dos Testes , Índices de Gravidade do TraumaRESUMO
This study evaluated the ability of the Orientation Log (O-Log) to predict cognitive outcome at rehabilitation discharge, as well as future neuropsychological outcome. The hypothesis was that patients who demonstrated better orientation upon admission would achieve superior functional cognitive outcome at discharge and on subsequent neuropsychological assessment. Sixty individuals receiving inpatient rehabilitation following a new-onset TBI participated. Orientation data was collected using the O-Log during morning bedside rounds. Outcome data was collected at 6 and 12 months post-injury. Significant correlations were found between the O-log and measures of memory, executive functioning, basic verbal skills, and estimated intellectual ability. When compared to the other predictor variables, step-wise multiple regression analyses revealed that the minimum O-Log score was the primary significant predictor of performance on six neuropsychological and functional outcome measures. Results of this study suggest that evaluating orientation with the O-Log during acute rehabilitation may reflect level of injury severity and aid in predicting cognitive outcome.
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Lesões Encefálicas/reabilitação , Transtornos Cognitivos/reabilitação , Testes Neuropsicológicos , Orientação , Atividades Cotidianas/classificação , Adolescente , Adulto , Idoso , Avaliação da Deficiência , Feminino , Escala de Coma de Glasgow , Humanos , Masculino , Pessoa de Meia-Idade , Alta do Paciente , Prognóstico , Resultado do TratamentoRESUMO
The current study was designed to assess the pattern and concentration of prenatal PCB exposure in the newborns of women who consumed Great Lakes fish. We compared the pattern and concentration of umbilical cord blood PCBs of 145 women who reported never having consumed Great Lakes fish to 134 women who reported consuming at least 40 PCB-equivalent fish lbs of Great Lakes fish in their lifetime (Lonky et al., 1996). Although the average levels of total PCBs in cord blood were exceedingly low (approximately 1.0 ppb), the data clearly indicated that both the proportion (mol%) and the absolute concentration (ppb) of the most heavily chlorinated and persistent PCB homologues (homologues C17-C19) were markedly elevated in the cord blood of fish eaters. This effect grew markedly as a function of the total PCBs detected in the sample. Moreover, the concentration of the most heavily chlorinated PCB homologues was significantly dependent on how recently the fish were consumed relative to pregnancy. The order of highly chlorinated PCB concentration was consumed fish throughout pregnancy > consumed fish up until pregnancy > stopped consuming fish in 1984 > never consumed Lake Ontario fish. In contrast, PCB homologues of light (Cl1-Cl3) or moderate (Cl4-Cl6) chlorination were unrelated to fish consumption. Analysis of the relationship between the PCB homologues in cord blood and their homologues in breast milk provided further converging evidence of these findings. While PCB homologues of light (Cl1-Cl3) or moderate (Cl4-Cl6) chlorination did not correlate with their breast milk homologues, the most persistent and heavily chlorinated PCB homologues (Cl7-Cl9) were significantly and positively correlated with breast milk levels. These data indicate that the most heavily chlorinated PCBs provide valid and reliable exposure information in a lean medium such as cord blood. We conclude that maternal consumption of Great Lakes fish increases the risk of prenatal exposure to the most heavily chlorinated PCB homologues.
Assuntos
Poluentes Ambientais/análise , Peixes , Contaminação de Alimentos , Bifenilos Policlorados/análise , Efeitos Tardios da Exposição Pré-Natal , Adulto , Animais , Ingestão de Alimentos , Exposição Ambiental/análise , Feminino , Sangue Fetal/química , Great Lakes Region , Humanos , Recém-Nascido , Leite Humano/química , Gravidez , Medição de Risco , Cordão Umbilical/químicaRESUMO
A study was conducted to assess local fish consumption patterns and their relationship to concentrations of total polychlorinated biphenyls (PCBs) in the serum of Mohawk men residing near three hazardous waste sites. From 1992 to 1995, 139 men were interviewed and donated a 20-ml venous blood sample. The results indicated that the men ate a mean of 21.2 local fish meals during the past year, compared with annual means of 27.7 meals 1-2 years before and 88.6 meals more than 2 years before (P<0.001 for test of trend). This change is probably a consequence of advisories issued against the consumption of local fish, since 97% of the men were aware of the advisories and two-thirds had changed their behavior as a result. Multiple regression analysis revealed that serum PCB levels increased with age (beta=0.036, P<0.001) and local fish consumption (beta=0.088, P=0.006). The data suggest that local fish consumption has contributed to body burdens in this population and that the advisories have been effective in modifying local fish consumption habits.