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1.
Int J Obes (Lond) ; 41(10): 1459-1466, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28435162

RESUMO

OBJECTIVE: To examine, in a population-based cohort of 3-year-old children, the association between self-regulation and exposure to the household routines of regular bedtime, regular mealtime and limits on watching television/video, and to determine whether self-regulation and these routines predict the risk of obesity at age 11. METHODS: Analyses included 10 955 children in the nationally representative UK Millennium Cohort Study. When children were age 3, parents reported whether children had a regular bedtime and mealtime, and the amount of television/video watched. Emotional and cognitive self-regulation at age 3 were assessed by parent-report with the Child Social Behaviour Questionnaire. Children's height and weight were measured at age 11 and obesity was defined using the International Obesity Task Force (IOTF) criteria. RESULTS: At age 3, 41% of children always had a regular bedtime, 47% always had a regular mealtime and 23% were limited to ⩽1 h television/video daily. At age 11, 6.2% of children were obese. All three household routines were significantly associated with better emotional self-regulation, but not better cognitive self-regulation. In a multi-variable logistic regression model, including emotional and cognitive self-regulation, all routines and controlling for sociodemographic covariates, a 1-unit difference in emotional self-regulation at age 3 was associated with an OR (95% CI) for obesity of 1.38 (1.11, 1.71) at age 11, and inconsistent bedtimes with an OR (95% CI) for obesity of 1.87 (1.39, 2.51) at age 11. There was no evidence that emotional self-regulation mediated the relationship between regular bedtimes and later obesity. Cognitive self-regulation was not associated with later obesity. CONCLUSIONS: Three-year-old children who had regular bedtimes, mealtimes and limits on their television/video time had better emotional self-regulation. Lack of a regular bedtime and poorer emotional self-regulation at age 3 were independent predictors of obesity at age 11.


Assuntos
Comportamento Infantil , Educação Infantil , Estilo de Vida , Pais , Obesidade Infantil/epidemiologia , Autocontrole , Criança , Pré-Escolar , Exercício Físico , Características da Família , Comportamento Alimentar , Feminino , Humanos , Modelos Logísticos , Estudos Longitudinais , Masculino , Pais/educação , Obesidade Infantil/etiologia , Prevalência , Estudos Prospectivos , Comportamento Sedentário , Sono , Comportamento Social , Televisão , Fatores de Tempo , Reino Unido/epidemiologia
2.
Clin Exp Allergy ; 46(6): 861-70, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26892490

RESUMO

BACKGROUND: Epidemiological surveys indicate that occupants of mold contaminated environments are at increased risk of respiratory symptoms. The immunological mechanisms associated with these responses require further characterization. OBJECTIVE: The aim of this study was to characterize the immunotoxicological outcomes following repeated inhalation of dry Aspergillus fumigatus spores aerosolized at concentrations potentially encountered in contaminated indoor environments. METHODS: Aspergillus fumigatus spores were delivered to the lungs of naïve BALB/cJ mice housed in a multi-animal nose-only chamber twice a week for a period of 13 weeks. Mice were evaluated at 24 and 48 h post-exposure for histopathological changes in lung architecture, recruitment of specific immune cells to the airways, and serum antibody responses. RESULT: Germinating A. fumigatus spores were observed in lungs along with persistent fungal debris in the perivascular regions of the lungs. Repeated exposures promoted pleocellular infiltration with concomitant epithelial mucus hypersecretion, goblet cell metaplasia, subepithelial fibrosis and enhanced airway hyperreactivity. Cellular infiltration in airways was predominated by CD4(+) T cells expressing the pro-allergic cytokine IL-13. Furthermore, our studies show that antifungal T cell responses (IFN-γ(+) or IL-17A(+) ) co-expressed IL-13, revealing a novel mechanism for the dysregulated immune response to inhaled fungi. Total IgE production was augmented in animals repeatedly exposed to A. fumigatus. CONCLUSIONS & CLINICAL RELEVANCE: Repeated inhalation of fungal aerosols resulted in significant pulmonary pathology mediated by dynamic shifts in specific immune populations and their cytokines. These studies provide novel insights into the immunological mechanisms and targets that govern the health outcomes that result from repeated inhalation of fungal bioaerosols in contaminated environments.


Assuntos
Fungos/imunologia , Hipersensibilidade/etiologia , Exposição por Inalação/efeitos adversos , Pneumonia/etiologia , Animais , Anticorpos Antifúngicos/imunologia , Aspergillus fumigatus/imunologia , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Hipersensibilidade/metabolismo , Hipersensibilidade/patologia , Camundongos , Fenótipo , Pneumonia/metabolismo , Pneumonia/patologia , Esporos Fúngicos/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo
3.
J Occup Environ Hyg ; 12 Suppl 1: S82-98, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26583909

RESUMO

Chemical allergens represent a significant health burden in the workplace. Exposures to such chemicals can cause the onset of a diverse group of adverse health effects triggered by immune-mediated responses. Common responses associated with workplace exposures to low molecular weight (LMW) chemical allergens range from allergic contact dermatitis to life-threatening cases of asthma. Establishing occupational exposure limits (OELs) for chemical allergens presents numerous difficulties for occupational hygiene professionals. Few OELs have been developed for LMW allergens because of the unique biological mechanisms that govern the immune-mediated responses. The purpose of this article is to explore the primary challenges confronting the establishment of OELs for LMW allergens. Specific topics include: (1) understanding the biology of LMW chemical allergies as it applies to setting OELs; (2) selecting the appropriate immune-mediated response (i.e., sensitization versus elicitation); (3) characterizing the dose (concentration)-response relationship of immune-mediated responses; (4) determining the impact of temporal exposure patterns (i.e., cumulative versus acute exposures); and (5) understanding the role of individual susceptibility and exposure route. Additional information is presented on the importance of using alternative exposure recommendations and risk management practices, including medical surveillance, to aid in protecting workers from exposures to LMW allergens when OELs cannot be established.


Assuntos
Alérgenos/toxicidade , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/normas , Relação Dose-Resposta Imunológica , Humanos , Hipersensibilidade/etiologia , Hipersensibilidade/imunologia , Doenças Profissionais/induzido quimicamente , Doenças Profissionais/imunologia , Medição de Risco , Níveis Máximos Permitidos
4.
Phys Rev Lett ; 109(2): 023001, 2012 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-23030156

RESUMO

We investigate the dependence of optical-lattice trapping potentials for Rydberg atoms on the angular portion of the atomic wave function. While ground-state atoms are pointlike in relation to an optical-lattice field, Rydberg-atom wave functions extend over a substantial fraction of the lattice period, which leads to a dependence of the lattice trapping potential on the angular portion of the spatial wave function. The angular dependence of the potential is measured using various (j, m(j)) levels of 85Rb Rydberg nD states (50≤n≤65) prepared in a one-dimensional optical lattice (wavelength 1064 nm) and a transverse dc electric field. The measured optical-lattice depths are found to be in agreement with theoretical results.

5.
Clin Radiol ; 67(12): 1207-11, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22784658

RESUMO

Thromboangiitis obliterans (Buerger's disease) is a rare, non-atherosclerotic, segmental, inflammatory vasculitis that most commonly involves small and medium-sized arteries, veins and nerves of the extremities and affects tobacco smokers between the ages of 25 and 45 years. The manifestations of Buerger's disease can be extremely variable and, therefore, awareness of the condition is important for both general and musculoskeletal radiologists. This paper presents the radiological appearance of the sequelae of Buerger's disease involving the upper and lower limbs.


Assuntos
Diagnóstico por Imagem , Extremidades/irrigação sanguínea , Tromboangiite Obliterante/diagnóstico , Adulto , Diagnóstico Diferencial , Humanos , Pessoa de Meia-Idade , Tromboangiite Obliterante/epidemiologia , Tromboangiite Obliterante/fisiopatologia
6.
Phys Rev Lett ; 107(26): 263001, 2011 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-22243153

RESUMO

Rubidium Rydberg atoms are laser excited and subsequently trapped in a one-dimensional optical lattice (wavelength 1064 nm). Efficient trapping is achieved by a lattice inversion immediately after laser excitation using an electro-optic technique. The trapping efficiency is probed via analysis of the trap-induced shift of the two-photon microwave transition 50S→51S. The inversion technique allows us to reach a trapping efficiency of 90%. The dependence of the efficiency on the timing of the lattice inversion and on the trap laser power is studied. The dwell time of 50D(5/2) Rydberg atoms in the lattice is analyzed using lattice-induced photoionization.

7.
Phys Rev E ; 104(5-2): 055205, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34942772

RESUMO

We report on simulations of strong, steady-state collisional planar plasma shocks with fully kinetic ions and electrons, independently confirmed by two fully kinetic codes (an Eulerian continuum and a Lagrangian particle-in-cell). While kinetic electrons do not fundamentally change the shock structure as compared with fluid electrons, we find an appreciable rearrangement of the preheat layer, associated with nonlocal electron heat transport effects. The electron heat-flux profile qualitatively agrees between kinetic- and fluid-electron models, suggesting a certain level of "stiffness," though substantial nonlocality is observed in the kinetic heat flux. We also find good agreement with nonlocal electron heat-flux closures proposed in the literature. Finally, in contrast to the classical hydrodynamic picture, we find a significant collapse in the "precursor" electric-field shock at the preheat layer leading edge, which correlates with the electron-temperature gradient relaxation.

8.
J Exp Med ; 139(5): 1154-74, 1974 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-4132992

RESUMO

Human macrophages derived from in vitro culture of peripheral blood monocytes were studied under a variety of conditions to determine their microbicidal capacity for the obligate intracellular protozoan, Toxoplasma gondii. The effect of macrophages on intracellular Toxoplasma was evaluated morphologically by light and phase microscopy and by autoradiography. When macrophages from dye test (DT)-negative or DT-positive individuals were infected with Toxoplasma in the presence of normal human serum, the organisms were able to multiply intracellularly with resultant destruction of the monolayer. Once organisms were intracellular, the presence of antibody-containing serum in the medium did not alter this inability of the macrophages to kill Toxoplasma. However, when Toxoplasma were incubated in the presence of heat-inactivated DT-positive serum just before infection of the monolayers, the intracellular organisms were inhibited or killed by normal macrophages. Attempts were made to activate macrophages in vitro to kill Toxoplasma. Macrophages incubated in the presence of sensitized lymphocytes and Streptokinase-Streptodornase (SK-SD) or Toxoplasma lysate antigen (TLA) were found to kill Toxoplasma when compared to macrophages incubated in the presence of lymphocytes from DT-negative individuals and TLA or lymphocytes alone. Thus, in vitro induction of resistance (both specifically and nonspecifically) in human macrophages was accomplished by culturing these cells in the presence of specifically sensitized lymphocytes and antigen. These results suggest that, as in the mouse model, activated human macrophages have the ability to inhibit or kill intracellular Toxoplasma and that these cells may be important as effector cells in cell-mediated immunity (CMI) to toxoplasmosis in man.


Assuntos
Macrófagos/imunologia , Toxoplasma/imunologia , Adolescente , Adulto , Anticorpos , Antígenos , Autorradiografia , Células Cultivadas , Humanos , Ativação Linfocitária , Linfócitos/metabolismo , Macrófagos/metabolismo , Masculino , Microscopia de Contraste de Fase , Pessoa de Meia-Idade , Monócitos , Coloração e Rotulagem , Estreptodornase e Estreptoquinase , Timidina/metabolismo , Trítio , Uridina/metabolismo
9.
Phys Rev Lett ; 104(17): 173001, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20482104

RESUMO

We demonstrate the state dependence of the ponderomotive energy shift of Rydberg atoms in an optical lattice using microwave spectroscopy. Unique to Rydberg atoms, this dependence results from a state-dependent aspect ratio between Rydberg-atom size and lattice period. A semiclassical simulation reproduces all features observed in the microwave spectra and indicates the presence of trapped Rydberg atoms.

10.
Eat Weight Disord ; 15(3): e166-72, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21150252

RESUMO

OBJECTIVE: The purpose of the present study was to compare obese patients screening positive or negative for attention deficit/hyperactivity disorder (ADHD) on pretreatment body mass index (BMI), weight loss following a 16 week clinic-based behavioral weight loss program, weight loss attempts, dietary and physical activity habits, perceived difficulty of weight control skills, and eating self-efficacy. DESIGN: Patients who completed a behavioral weight loss program were approached to complete questionnaires on ADHD and eating habits. Medical charts were reviewed to obtain weight at pre- and post-treatment. RESULTS: Participants (N=63) were 75% female, mean age was 49 (SD=10.3), mean body mass index (BMI) was 41.4 kg/m² (SD=6.8) and 30% screened positive for ADHD on the Adult ADHD Symptom Rating Scale. Participants screening positive for ADHD did not have a higher BMI at baseline (p=0.41), but reported more previous weight loss attempts (p=0.01) and lost less weight (p=0.02) than participants who screened negative. Participants screening positive also reported consuming fast food meals more frequently (p=0.04), higher levels of emotional eating (p=0.002), greater difficulty with weight control skills (p=0.01), and lower eating self-efficacy (p=0.001). CONCLUSION: Attention-related problems appear to be common among weight treatment-seeking samples and represent a significant barrier to weight control that has not yet been addressed in the literature.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/terapia , Obesidade/terapia , Autoeficácia , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Índice de Massa Corporal , Peso Corporal , Dietoterapia/psicologia , Terapia por Exercício/psicologia , Comportamento Alimentar/psicologia , Feminino , Promoção da Saúde , Humanos , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/fisiopatologia , Obesidade/psicologia , Inquéritos e Questionários
11.
Chemosphere ; 255: 126864, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32402869

RESUMO

This work demonstrates the ability of aqueous phase corona discharge to chemically reduce bromate and chlorate ions, common disinfection byproducts, to bromide and chloride ions, respectively. A high voltage pulse was applied to a needle electrode, submerged in the target solution, to generate highly reactive oxidative and reductive species in a temperature-controlled reactor. Optimal water matrix conditions were sought through changing the solution pH, temperature, and dissolved oxygen concentration. Additionally, several oxidative species scavengers were investigated, including methanol, ethanol, sucrose, and D-sorbitol. Chemical reduction rates were improved at low pH (3.5). The presence of dissolved oxygen significantly reduced the chemical reduction rate, and thus high solution temperature (50 °C) also achieved better chemical reduction. All oxidative species scavengers improved the chemical reduction rate; however, methanol and ethanol were superior as these compounds generate hydrogen bubbles in the presence of plasma, which deoxygenates the solution further improving the chemical reduction rate. The application of this technology to 30 µM bromate and chlorate solutions, under optimal water matrix conditions and with the addition of 72 g/L-COD methanol, achieved greater than 95% removal of the target compounds within 60 min. Increasing the initial concentration of the target compounds to 300 µM required 90 and 150 min to achieve similar chemical reductions for bromate and chlorate, respectively.


Assuntos
Bromatos/química , Cloratos/química , Poluentes Químicos da Água/química , Brometos/química , Cloretos , Cloro , Desinfecção , Hidrogênio , Concentração de Íons de Hidrogênio , Metanol , Oxirredução , Temperatura , Água/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos
12.
Nanotoxicology ; 14(8): 1096-1117, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32909489

RESUMO

Gold nanoparticles (AuNP) are largely biocompatible; however, many studies have demonstrated their potential to modulate various immune cell functions. The potential allergenicity of AuNP remains unclear despite the recognition of gold as a common contact allergen. In these studies, AuNP (29 nm) dermal sensitization potential was assessed via Local Lymph Node Assay (LLNA). Soluble gold (III) chloride (AuCl3) caused lymph node (LN) expansion (SI 10.9), whereas bulk particles (Au, 942 nm) and AuNP did not. Next, the pulmonary immune effects of AuNP (10, 30, 90 µg) were assessed 1, 4, and 8 days post-aspiration. All markers of lung injury and inflammation remained unaltered, but a dose-responsive increase in LN size was observed. Finally, mice were dermally-sensitized to AuCl3 then aspirated once, twice, or three times with Au or AuNP in doses normalized for mass or surface area (SA) to assess the impact of existing contact sensitivity to gold on lung immune responses. Sensitized animals exhibited enhanced responsivity to the metal, wherein subsequent immune alterations were largely conserved with respect to dose SA. The greatest increase in bronchoalveolar lavage (BAL) lymphocyte number was observed in the high dose group - simultaneous to preferential expansion of BAL/LN CD8+ T-cells. Comparatively, the lower SA-based doses of Au/AuNP caused more modest elevations in BAL lymphocyte influx (predominantly CD4+ phenotype), exposure-dependent increases in serum IgE, and selective expansion/activation of LN CD4+ T-cells and B-cells. Overall, these findings suggest that AuNP are unlikely to cause sensitization; however, established contact sensitivity to gold may increase immune responsivity following pulmonary AuNP exposure.


Assuntos
Alérgenos/toxicidade , Compostos de Ouro/toxicidade , Ouro/toxicidade , Pulmão/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Pele/efeitos dos fármacos , Animais , Proteínas Sanguíneas/metabolismo , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Feminino , Ensaio Local de Linfonodo , Pulmão/imunologia , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Tamanho da Partícula , Pele/imunologia , Propriedades de Superfície
13.
Osteoarthritis Cartilage ; 17(10): 1341-9, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19410029

RESUMO

OBJECTIVE: To investigate the ability of delayed gadolinium-enhanced magnetic resonance (MR) imaging of cartilage (dGEMRIC) and T2 mapping to evaluate the quality of repair tissue after microfracture. DESIGN: Twelve knees from 12 goats were studied. An osteochondral defect (diameter, 6mm; depth, 3mm) with microfracture was created in the weight-bearing aspect of both the medial and lateral femoral condyles. Goats were euthanized at 24 weeks (n=6) and 48 weeks (n=6) postsurgery. Pre-contrast R1 (R1pre) and post-contrast R1 (R1post) measurements for dGEMRIC and a pre-contrast T2 measurement for T2 mapping were performed with a 3T MR imaging system. MR imaging findings were compared with histological and biochemical assessments. RESULTS: In native cartilage, significant correlations were observed between the R1post and the glycosaminoglycan (GAG) concentration, as well as DeltaR1 (difference between the R1pre and R1post) and the GAG concentration (P<0.05). In repair tissue, a significant correlation was observed between DeltaR1 and the GAG concentration (P<0.05), but not between the R1post and the GAG concentration. In both repair tissue and native cartilage, no correlation was observed between T2 and the water concentration or between T2 and the hydroxyproline (HP) concentration. A zonal variation of T2 and a clear dependence of T2 on the angles relative to B0 were observed in native cartilage, but not in repair tissue. CONCLUSION: dGEMRIC with DeltaR1 measurement might be useful for the evaluation of the GAG concentration in repair tissue after microfracture. T2 mapping might be useful for the differentiation of repair tissue after microfracture from native cartilage; however, its potential to assess the specific biochemical markers in native cartilage as well as repair tissue may be limited.


Assuntos
Artroplastia Subcondral , Cartilagem Articular/química , Gadolínio , Glicosaminoglicanos/análise , Traumatismos do Joelho/diagnóstico , Imageamento por Ressonância Magnética/métodos , Animais , Cartilagem Articular/anatomia & histologia , Cartilagem Articular/lesões , Meios de Contraste , Modelos Animais de Doenças , Cabras , Aumento da Imagem/métodos , Traumatismos do Joelho/metabolismo , Traumatismos do Joelho/patologia
14.
Eur Radiol ; 19(3): 701-12, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18815789

RESUMO

Fifty-nine cases of lesions presenting in the patella were identified after review of the databases of four European bone tumour registries. Of the 59 cases, 46% were non neoplastic, 39% were benign and 15% were malignant. The commonest benign neoplasm was giant cell tumour (GCT) (11 cases). Younger patients were more likely to have a benign neoplasm. Lesions in patients less than 40 years of age included giant cell tumour, chondroblastoma, aneurysmal bone cyst (ABC), osteomyelitis, osteoid osteoma and solitary bone cyst. In patients older than 40 years, the following were common lesions: intra-osseous gout, metastasis and intra-osseous ganglion. Expansion of the patella with thinning of cortex was seen more commonly in GCT and brown tumour in hyperparathyroidism. There was associated soft tissue extension in gout and malignant lesions.


Assuntos
Neoplasias Ósseas/patologia , Tumores de Células Gigantes/patologia , Patela/patologia , Adolescente , Adulto , Fatores Etários , Neoplasias Ósseas/diagnóstico , Diagnóstico Diferencial , Feminino , Tumores de Células Gigantes/diagnóstico , Humanos , Masculino , Oncologia/métodos , Pessoa de Meia-Idade , Metástase Neoplásica , Radiologia/métodos
15.
Brain Res ; 1218: 1-12, 2008 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-18513705

RESUMO

During aging, changes in the structure of the cerebral cortex of the rat have been seen, but potential changes in neuron number remain largely unexplored. In the present study, stereological methods were used to examine neuron number in the medial prefrontal cortex and primary visual cortex of young adult (85-90 days of age) and aged (19-22 months old) male and female rats in order to investigate any age-related losses. Possible sex differences in aging were also examined since sexually dimorphic patterns of aging have been seen in other measures. An age-related loss of neurons (18-20%), which was mirrored in volume losses, was found to occur in the primary visual cortex in both sexes in all layers except IV. Males, but not females, also lost neurons (15%) from layer V/VI of the ventral medial prefrontal cortex and showed an overall decrease in volume of this region. In contrast, dorsal medial prefrontal cortex showed no age-related changes. The effects of aging clearly differ among regions of the rat brain and to some degree, between the sexes.


Assuntos
Envelhecimento , Neurônios/fisiologia , Córtex Pré-Frontal/citologia , Caracteres Sexuais , Córtex Visual/citologia , Análise de Variância , Animais , Contagem de Células/métodos , Morte Celular/fisiologia , Feminino , Masculino , Ratos , Ratos Long-Evans
16.
J Clin Invest ; 95(1): 39-45, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7814640

RESUMO

Chronic metabolic acidosis has been previously shown to stimulate protein degradation. To evaluate the effects of chronic metabolic acidosis on nitrogen balance and protein synthesis we measured albumin synthesis rates and urinary nitrogen excretion in eight male subjects on a constant metabolic diet before and during two different degrees of chronic metabolic acidosis (NH4Cl 2.1 mmol/kg body weight, low dose group, and 4.2 mmol/kg body weight, high dose group, orally for 7 d). Albumin synthesis rates were measured by intravenous injection of [2H5ring]phenylalanine (43 mg/kg body weight, 7.5 atom percent and 15 atom percent, respectively) after an overnight fast. In the low dose group, fractional synthesis rates of albumin decreased from 9.9 +/- 1.0% per day in the control period to 8.4 +/- 0.7 (n.s.) in the acidosis period, and from 8.3 +/- 1.3% per day to 6.3 +/- 1.1 (P < 0.001) in the high dose group. Urinary nitrogen excretion increased significantly in the acidosis period (sigma delta 634 mmol in the low dose group, 2,554 mmol in the high dose group). Plasma concentrations of insulin-like growth factor-I, free thyroxine and tri-iodothyronine were significantly lower during acidosis. In conclusion, chronic metabolic acidosis causes negative nitrogen balance and decreases albumin synthesis in humans. The effect on albumin synthesis may be mediated, at least in part, by a suppression of insulin-like growth factor-I, free thyroxine and tri-iodothyronine.


Assuntos
Acidose/metabolismo , Compostos de Nitrogênio/metabolismo , Albumina Sérica/biossíntese , Acidose/induzido quimicamente , Ácidos/sangue , Adulto , Álcalis/sangue , Cloreto de Amônio/efeitos adversos , Análise Química do Sangue , Peso Corporal , Doença Crônica , Humanos , Fator de Crescimento Insulin-Like I/análise , Masculino , Compostos de Nitrogênio/urina , Tiroxina/sangue , Tri-Iodotironina/sangue
17.
Neuroscience ; 145(1): 357-69, 2007 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-17207583

RESUMO

Although many aspects of sensory processing are qualitatively similar in awake and anesthetized subjects, important state-dependent differences are known to exist. To investigate the effects of anesthesia on temporal processing in rat auditory cortex, multi-unit neural responses to trains of broadband clicks were recorded prior to, 15 min following, and 5 h following the administration of a ketamine-based anesthetic. While responses to clicks in isolation were relatively stable between states, responses to subsequent clicks exhibited increases in latency, peak latency, response duration, and post-onset suppression under anesthesia. Ketamine anesthetic reduced the maximum rate at which multi-unit clusters entrained to repeated clicks. No multi-unit clusters entrained to stimulus presentation rates greater than 33 Hz under anesthesia, compared with 85% and 81% in the pre- and post-anesthetic condition, respectively. Anesthesia also induced oscillatory activity that was not present in awake subjects. Finally, ketamine anesthesia abolished all tonic excitatory and suppressive nonsynchronous responses to click trains. The results of this study suggest that ketamine-based anesthesia significantly alters neural coding of broadband click trains in auditory cortex.


Assuntos
Anestesia , Córtex Auditivo/fisiologia , Potenciais Evocados Auditivos/fisiologia , Estimulação Acústica/métodos , Analgésicos/farmacologia , Animais , Eletroencefalografia , Potenciais Evocados Auditivos/efeitos dos fármacos , Feminino , Ketamina/farmacologia , Ratos
18.
Hear Res ; 213(1-2): 107-17, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16466874

RESUMO

This study examines the ability of multi-unit clusters (MUCs) in layer IV/V of primary auditory cortex of the awake rat to respond to a series of broadband click trains. The data from 113 multi-unit clusters were analyzed for synchronous and nonsynchronized responses using several methods. Synchronous responses were measured using window analysis, circular statistics and spectral analysis. Nonsynchronous responses were measured during different time intervals during the click train (first 50 ms, 50-450 ms, and the entire click train). The results demonstrate that multi-unit clusters are capable of synchronizing to clicks at rates up to 166 Hz. The mean synchronization boundary (limiting rate) for the group was found to be 72 Hz. Mean peak response rate, mean response duration, and mean time-to-peak response decreased as the stimulus presentation rate (SPR) increased, resulting in a temporal sharpening of the population response. For fast SPRs (>50 Hz), 50% of MUCs exhibited nonsynchronous responses in which the firing rate increased with SPR, although this activity was most prevalent during the first 50 ms of the response. Sustained increases in firing rate with SPR were seen in 8% of the MUCs, while another 38% of MUCs exhibited sustained decreases during the click train.


Assuntos
Estimulação Acústica/métodos , Córtex Auditivo/fisiologia , Análise de Variância , Animais , Estimulação Elétrica , Eletrodos , Feminino , Ratos , Ratos Sprague-Dawley
19.
J Natl Cancer Inst ; 87(14): 1056-60, 1995 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-7616596

RESUMO

BACKGROUND: Lung cancer is the leading cause of cancer deaths in the United States. A long-standing goal of cancer researchers has been to develop tests that would facilitate earlier diagnosis and treatment of lung cancer and thereby decrease mortality from this disease. Because cancer results from the accumulation of a variety of genetic events (e.g., mutations, rearrangements, and deletions) in genes controlling cell growth and differentiation, these changes might serve as diagnostically useful molecular markers. Activation of the K-ras oncogene by point mutations in codon 12, which occurs in many cases of lung adenocarcinoma, may serve as one such clinically useful molecular marker. For detection of K-ras point mutations in bronchoalveolar lavage fluid, in which small numbers of malignant cells are mixed with a population of predominantly genetically normal cells, the sensitivity of commonly used assays for ras mutations risks false-negative results. PURPOSE: By applying a highly sensitive assay, we investigated whether detection of K-ras codon 12 mutations in samples of bronchoalveolar lavage fluid could be clinically useful in diagnosing lung cancer. METHODS: We developed a highly sensitive assay for detecting K-ras codon 12 mutations based on an enriched polymerase chain reaction (PCR) technique. This technique was applied to 87 specimens of bronchoalveolar lavage fluid specimens that were obtained from 86 patients, and associated tumor biopsy specimens obtained from 35 of these patients who underwent diagnostic bronchoscopy for clinically suspected lung cancer. Statistical comparisons were performed by using the two-tailed Fisher's exact test [corrected]. RESULTS: Of 52 patients with confirmed lung cancer, samples of bronchoalveolar lavage fluid from 16 patients contained K-ras codon 12 mutations, including 14 (56%) of 25 patients with lung adenocarcinomas, one (33%) of three with bronchoalveolar carcinomas, one (20%) of five with large-cell carcinomas, and none of the 14 with squamous cell carcinomas. Mutations were detected in four additional cases in which cancer was suspected but had not been histologically confirmed. Tissue samples from 35 of the patients all yielded the identical K-ras codon 12 genotype found in the corresponding samples of bronchoalveolar lavage fluid. No mutation was found in any sample from 30 patients with diagnoses other than non-small-cell lung cancer. Thus, for those cases in which tissue was available and tested, the sensitivity and specificity of detecting K-ras mutations in bronchoalveolar lavage fluid for diagnosing K-ras mutation-positive lung cancer were both 100%. For nine patients, K-ras mutations were detected in bronchoalveolar lavage fluid obtained during otherwise nondiagnostic bronchoscopies. CONCLUSIONS: Our data demonstrate that sensitive detection of K-ras codon 12 mutations can serve as an important adjunct to cytology in the diagnosis of lung cancer. IMPLICATIONS: Detection of these mutations could lead to earlier cancer diagnosis and less need for invasive diagnostic procedures.


Assuntos
Líquido da Lavagem Broncoalveolar , Carcinoma/diagnóstico , Carcinoma/genética , Genes ras/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Mutação Puntual , Broncoscopia , Estudos de Casos e Controles , Códon , Humanos , Reação em Cadeia da Polimerase
20.
Vasa ; 34(1): 62-5, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15786943

RESUMO

We describe the successful selective coil embolization of an infected superior gluteal pseudoaneurysm secondary to methicillin-resistant Staphylococcus aureus (MRSA) in a 36-year old women. The patient presented with a long history of drug abuse and perisacral abscesses due to chronic sacroilitis. The chosen strategy provides a safe and successful management of infected false gluteal artery aneurysm.


Assuntos
Abscesso/complicações , Falso Aneurisma/terapia , Aneurisma Infectado/terapia , Artrite Infecciosa/complicações , Nádegas/irrigação sanguínea , Embolização Terapêutica , Resistência a Meticilina , Articulação Sacroilíaca , Infecções Estafilocócicas/terapia , Abscesso/diagnóstico , Adulto , Falso Aneurisma/diagnóstico , Aneurisma Infectado/diagnóstico , Angiografia , Artrite Infecciosa/diagnóstico , Bacteriemia/complicações , Bacteriemia/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Infecções Estafilocócicas/diagnóstico , Tomografia Computadorizada por Raios X
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