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1.
Clin Exp Immunol ; 189(1): 36-46, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28295207

RESUMO

The role of viral infections in adverse pregnancy outcomes has gained interest in recent years. Innate immune pattern recognition receptors (PRRs) and their signalling pathways, that yield a cytokine output in response to pathogenic stimuli, have been postulated to link infection at the maternal-fetal interface and adverse pregnancy outcomes. The objective of this study was to investigate the expression and functional response of nucleic acid ligand responsive Toll-like receptors (TLR-3, -7, -8 and -9), and retinoic acid-inducible gene 1 (RIG-I)-like receptors [RIG-I, melanoma differentiation-associated protein 5 (MDA5) and Laboratory of Genetics and Physiology 2(LGP2)] in human term gestation-associated tissues (placenta, choriodecidua and amnion) using an explant model. Immunohistochemistry revealed that these PRRs were expressed by the term placenta, choriodecidua and amnion. A statistically significant increase in interleukin (IL)-6 and/or IL-8 production in response to specific agonists for TLR-3 (Poly(I:C); low and high molecular weight), TLR-7 (imiquimod), TLR-8 (ssRNA40) and RIG-I/MDA5 (Poly(I:C)LyoVec) was observed; there was no response to a TLR-9 (ODN21798) agonist. A hierarchical clustering approach was used to compare the response of each tissue type to the ligands studied and revealed that the placenta and choriodecidua generate a more similar IL-8 response, while the choriodecidua and amnion generate a more similar IL-6 response to nucleic acid ligands. These findings demonstrate that responsiveness via TLR-3, TLR-7, TLR-8 and RIG-1/MDA5 is a broad feature of human term gestation-associated tissues with differential responses by tissue that might underpin adverse obstetric outcomes.


Assuntos
Proteína DEAD-box 58/metabolismo , Helicase IFIH1 Induzida por Interferon/metabolismo , Placenta/imunologia , RNA Helicases/metabolismo , Receptores de Reconhecimento de Padrão/imunologia , Receptores Toll-Like/metabolismo , Feminino , Humanos , Imunidade Inata , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Ácidos Nucleicos/imunologia , Poli I-C/imunologia , Gravidez , Receptores Imunológicos , Transdução de Sinais , Técnicas de Cultura de Tecidos , Receptores Toll-Like/agonistas
2.
Phys Rev Lett ; 104(16): 161101, 2010 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-20482038

RESUMO

We report studies of ultrahigh-energy cosmic-ray composition via analysis of depth of air shower maximum (X(max)), for air shower events collected by the High-Resolution Fly's Eye (HiRes) observatory. The HiRes data are consistent with a constant elongation rate d/d[log(E)] of 47.9+/-6.0(stat)+/-3.2(syst) g/cm2/decade for energies between 1.6 and 63 EeV, and are consistent with a predominantly protonic composition of cosmic rays when interpreted via the QGSJET01 and QGSJET-II high-energy hadronic interaction models. These measurements constrain models in which the galactic-to-extragalactic transition is the cause of the energy spectrum ankle at 4x10(18) eV.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31025885

RESUMO

Objective: Susceptibility-weighted imaging (SWI) has been used to identify neurodegeneration in amyotrophic lateral sclerosis (ALS) through qualitative gross visual comparison of signal intensity. The aim of this study was to quantitatively identify cerebral degeneration in ALS on SWI using texture analysis. Methods: SW images were acquired from 17 ALS patients (58.4 ± 10.3 years, 13M/4F, ALSFRS-R 41.2 ± 4.1) and 18 healthy controls (56.3 ± 17.6 years, 9M/9F) at 4.7 tesla. Textures were computed within the precentral gyrus and basal ganglia and compared between patients and controls using ANCOVA with age and gender as covariates. Texture features were correlated with clinical measures in patients. Texture features found to be significantly different between patients and controls in the precentral gyrus were then used in a whole-brain 3D texture analysis. Results: The texture feature autocorrelation was significantly higher in ALS patients compared to healthy controls in the precentral gyrus and basal ganglia (p < 0.05). Autocorrelation correlated significantly with clinical measures such as disease progression rate and finger tapping speed (p < 0.05). Whole brain 3D texture analysis using autocorrelation revealed differences between ALS patients and controls within the precentral gyrus on SWI images (p < 0.001). Conclusion: Texture analysis on SWI can quantitatively identify cerebral differences between ALS patients and controls.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Progressão da Doença , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Esclerose Lateral Amiotrófica/metabolismo , Encéfalo/metabolismo , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Estudos Prospectivos
4.
J Steroid Biochem Mol Biol ; 112(4-5): 179-85, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18955142

RESUMO

Estrogen exposure and metabolism may play an important role in the development of estrogen-sensitive cancers in postmenopausal women. In this study we investigated whether past oral contraceptive (OC) administration or current dietary isoflavonoids (IF) affected expression and/or activity of steroid hormone-metabolizing cytochrome P450 (CYP) enzymes using complementary primate and cell culture models. One-hundred-eighty-one female cynomolgus macaques were randomized to receive OC or nothing for 26 months premenopausally, then ovariectomized and randomized to one of three diets for 36 months: an IF-depleted soy protein isolate (Soy-) diet, a Soy diet with IF (Soy+), or a Soy- diet supplemented with conjugated equine estrogens (CEE). Prior OC-treatment significantly reduced CYP gene expression in the mammary gland (< or =60% of OC-). Dietary IFs had no effect on CYP expression, while CEE-treatment decreased CYP1A1 and increased CYP3A4 mRNA in a tissue-specific manner. For in vitro studies, we measured effects of the isoflavonoids genistein, daidzein and equol on CYP activity using intact V79 cells stably transfected to express CYP1A1, CYP1B1, or CYP3A4. All three IFs significantly altered CYP activity in a dose-dependent and isoform-specific manner (20-95% inhibition versus controls). These results suggest potential mechanisms for prior OC and dietary IF effects on cancer risk in estrogen-responsive tissues.


Assuntos
Hidrocarboneto de Aril Hidroxilases/metabolismo , Anticoncepcionais Orais/farmacologia , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP3A/metabolismo , Isoflavonas/farmacologia , Animais , Linhagem Celular , Ilhas de CpG/efeitos dos fármacos , Cricetinae , Cricetulus , Citocromo P-450 CYP1B1 , Dieta , Equol , Feminino , Expressão Gênica/efeitos dos fármacos , Genisteína/farmacologia , Fígado/enzimologia , Macaca fascicularis , Glândulas Mamárias Animais/enzimologia , RNA Mensageiro/metabolismo
5.
Mol Cell Biol ; 14(8): 5558-68, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8035830

RESUMO

The myeloperoxidase (MPO) and neutrophil elastase genes are expressed specifically in immature myeloid cells. The integrity of a polyomavirus enhancer core sequence, 5'-AACCACA-3', is critical to the activity of the murine MPO proximal enhancer. This element binds two species, myeloid nuclear factors 1 alpha and 1 beta (MyNF1 alpha and -beta), present in 32D cl3 myeloid cell nuclear extracts. The levels of the MyNF1s increase during early 32D cl3 cell granulocytic differentiation. Both MyNF1 alpha and -beta supershift with an antiserum raised by using a peptide derived from the N terminus of polyomavirus enhancer-binding protein 2/core-binding factor (PEBP2/CBF) alpha subunit. The specific peptide inhibits these supershifts. In vitro-translated PEBP2/CBF DNA-binding domain binds the murine MPO PEBP2/CBF site. An alternate PEBP2/CBF consensus site, 5'-GACCGCA-3', but not a simian virus 40 enhancer core sequence, 5'-TTCCACA-3', binds the MyNF1s in vitro and activates a minimal murine MPO-thymidine kinase promoter in vivo. The murine neutrophil elastase gene 100-bp 5'-flanking sequences contain several functional elements, including potential binding sites for PU.1, C/EBP, c-Myb, and PEBP2/CBF. The functional element 5'-GGCCACA-3' located at positions -66 to 72 differs from the PEBP2/CBF consensus (5'-PuACCPuCA-3') only by an A-to-G transition at position 2. This DNA element binds MyNF1 alpha and -beta weakly. The N terminis of two PEBP2/CBF alpha subunit family members, PEBP2 alpha A and PEBP2 alpha B (murine AML1), are nearly identical, and 32D c13 cl3 cells contain both corresponding mRNAs. Since t(8;21), t(3;21), and inv(16), associated with myeloid leukemias, disrupt subunits of PEBP2/CBF, we speculate that the resulting oncoproteins, AML1-ETO, AML1-EAP, AML1-Evi1, and CBF beta-MYH11, inhibit early myeloid differentiation.


Assuntos
Proteínas de Ligação a DNA/genética , Regulação Enzimológica da Expressão Gênica , Leucócitos/enzimologia , Proteínas de Neoplasias , Elastase Pancreática/genética , Peroxidase/genética , Regiões Promotoras Genéticas , Fatores de Transcrição/genética , Animais , Sequência de Bases , Sítios de Ligação , Clonagem Molecular , Subunidade alfa 1 de Fator de Ligação ao Core , Subunidades alfa de Fatores de Ligação ao Core , Subunidade beta de Fator de Ligação ao Core , Fatores de Ligação ao Core , Técnicas In Vitro , Elastase de Leucócito , Camundongos , Dados de Sequência Molecular , Proteínas Nucleares/metabolismo , Oligodesoxirribonucleotídeos/química , RNA Mensageiro/genética , Fator de Transcrição AP-2
6.
Exp Hematol ; 28(2): 140-7, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10706069

RESUMO

OBJECTIVE: The Asp816Val c-kit activating mutation is detectable in the peripheral blood cells of some patients with mastocytosis and in lesional skin biopsies obtained from adult patients with urticaria pigmentosa. These observations led to the conclusion that this mutation is present in mast cells and mast cell precursors that express c-kit. However, the distribution of the Asp816Val mutation among hematopoietic lineages is unknown. To determine the distribution of the Asp816Val mutation among hematopoietic lineages and to explore its relationship to clinical disease, we examined cells bearing differentiation markers for myelomonocytic cells as well as T and B lymphocytes, in both peripheral blood and bone marrow obtained from patients with mastocytosis. MATERIALS AND METHODS: The presence of Asp816Val c-kit mutation in cells magnetically sorted from peripheral blood or bone marrow according to surface differentiation markers was studied by reverse transcriptase polymerase chain reaction (RT-PCR) restriction fragment length polymorphism (RFLP) analysis. The surface expression of c-kit was determined by flow cytometry. RESULTS: The mutation was detectable by RT-PCR in at least one cell lineage in the bone marrow in 7 of 7 patients examined and in the peripheral blood of 11 of 11 adult patients with urticaria pigmentosa and indolent disease. The mutation was identified most frequently in B cells and myeloid cells. Flow cytometric analysis demonstrated that the differentiated cells expressing mutated c-kit were negative for surface KIT. CONCLUSION: These results are consistent with the conclusion that the c-kit Asp816Val mutation occurs in an early progenitor cell and is carried by myelomonocytic cells, T cells, and B cells in addition to mast cells. However, unlike mast cells, these myelomonocytic cells, T cells, and B cells do not concomitantly express surface c-kit and thus may be less susceptible to the effects of this mutation.


Assuntos
Linfócitos B/metabolismo , Mastocitose/genética , Monócitos/metabolismo , Mutação , Proteínas Proto-Oncogênicas c-kit/genética , Linfócitos T/metabolismo , Adulto , Idoso , Linhagem da Célula , Feminino , Humanos , Lactente , Masculino , Mastocitose/sangue , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-kit/biossíntese , Fator de Células-Tronco/metabolismo
7.
Biochem Pharmacol ; 32(5): 827-30, 1983 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-6838630

RESUMO

The effect of metformin (N,N-dimethylbiguanide) on the rate-limiting enzymes of cholesterol metabolism was observed. 3-Hydroxy-3-methylglutaryl-CoA reductase (HMG-CoA reductase) and acyl-CoA-cholesterol acyltransferase (ACAT) activities were estimated in hepatic microsomal and intestinal cell preparations from normal and alloxan-diabetic rats. Metformin administration had no effect on either hepatic enzyme. Intestinal ACAT activity was significantly decreased in the metformin-treated rats when compared with controls (P less than 0.001). Intestinal HMG-CoA reductase activity was not significantly affected. Diabetic rats showed a significantly higher intestinal HMG-CoA reductase activity when compared with controls (P less than 0.001). Intestinal ACAT activity in the diabetic group was similar to control values. Metformin administration to diabetic rats caused a marked decrease in both intestinal HMG-CoA reductase activity (P less than 0.001) and ACAT activity (P less than 0.002). It is concluded that the effect of metformin on the intestinal cholesterol enzyme system may be responsible for its cholesterol-lowering action.


Assuntos
Aciltransferases/metabolismo , Colesterol/metabolismo , Hidroximetilglutaril-CoA Redutases/metabolismo , Intestinos/enzimologia , Metformina/farmacologia , Microssomos Hepáticos/enzimologia , Esterol O-Aciltransferase/metabolismo , Animais , Diabetes Mellitus Experimental/enzimologia , Masculino , Ratos , Ratos Endogâmicos
9.
Obstet Gynecol ; 95(3): 391-5, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10711550

RESUMO

OBJECTIVE: To review the experience of women who conceived after developing mastocytosis and who were observed at the National Institutes of Health. METHODS: We reviewed our patient database for the years 1984-1998 to identify women with mastocytosis who had conceived. We then reviewed each woman's record, asked each woman to complete a questionnaire, and with permission wrote outside hospitals to obtain records of each labor and delivery. RESULTS: We identified eight women who had become pregnant. These women delivered a total of 11 live infants. In approximately a third of the pregnancies, patients experienced worsening of symptoms. They often used fewer medications during pregnancy because of safety concerns, and no greater incidence of adverse reactions was noted. Antihistamines were used most commonly, followed by oral prednisone. Medications used during delivery were well tolerated and included epidural analgesics. Neonates were generally healthy. None to date have developed urticaria pigmentosa or systemic mastocytosis. CONCLUSION: A subset of women with mastocytosis might have had exacerbated mastocytosis during and after pregnancy, but labor and delivery progressed normally. Infants were born generally healthy and were without mastocytosis. Thus there appears to be no absolute contraindication to pregnancy for women with mastocytosis, although women should be aware that the choice to have a child is not without some added risk.


Assuntos
Mastocitose , Complicações na Gravidez , Resultado da Gravidez , Adulto , Analgesia Obstétrica , Feminino , Humanos , Mastocitose/complicações , Gravidez , Prurido/etiologia , Estudos Retrospectivos
10.
J Emerg Med ; 8(5): 575-82, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2254605

RESUMO

Pregnant women in American society today are at significant risk of injury during a period when physiologic responses to trauma, as well as expected findings of physical examination and laboratory evaluation are altered by the on-going pregnancy. Changes in anatomy, hemodynamics, respiratory function, gastrointestinal function, and hematologic and hemostatic parameters impact upon the approach to the evaluation and management of injured pregnant women. Maternal outcome is dependent on the nature and extent of injury and on the delivery of appropriate care. Fetal outcome relates to the magnitude of direct injury and the maternal physiologic response. It is imperative that all physicians involved in clinical evaluation and management of injured pregnant women understand the changes engendered by pregnancy and their effects upon the mother, the fetus, and the decision-making process. The best way to secure a favorable outcome for both mother and fetus is a standardized planned approach to care provided by a team cognizant of these changes.


Assuntos
Complicações na Gravidez/diagnóstico , Ferimentos e Lesões/diagnóstico , Testes de Coagulação Sanguínea , Feminino , Humanos , Testes de Função Renal , Gravidez , Complicações na Gravidez/sangue , Testes de Função Respiratória , Útero/lesões , Ferimentos e Lesões/sangue
11.
Behav Modif ; 22(3): 243-61, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9722474

RESUMO

The purpose of this study was to examine the trainability of anticipation in intermediate tennis players. In particular, the study examined whether video presentations could improve on-court tennis serve returns. A series of separate A-B designs across 6 participants was implemented, with baseline and intervention scores for on-court serve-return performance being recorded. Intervention consisted of 2 phases: a training phase and an on-court testing phase. The training phase, which employed a changing criterion design, consisted of a series of tennis-serve video presentations that were replayed with gradually increasing speed. All serves were occluded on racquet/ball contact, and participants were asked to predict the type, depth, and width of the serve. Following completion of the training phase, participants were again tested on their ability to return tennis serves on the tennis court. On-court results suggested that anticipation ability and performance did improve as a result of the intervention.


Assuntos
Terapia Comportamental , Destreza Motora , Tênis/psicologia , Adulto , Aptidão/fisiologia , Atenção , Tomada de Decisões , Feminino , Humanos , Masculino , Tempo de Reação , Tênis/fisiologia , Gravação de Videoteipe
12.
Health Phys ; 60(5): 691-3, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-1850391

RESUMO

Phosphogypsum is the by-product resulting from phosphoric acid or phosphate fertilizer production. The phosphate are used in these chemical processes contains the naturally occurring radioactive material U and all its subsequent decay products. During processing, the U generally remains in the phosphoric acid product, while the daughter, 226Ra, tends to be concentrated in the phosphogypsum. Phosphogypsum has physical properties that make it useful as a sub-base for roadways, parking lots, and similar construction. A radiological evaluation, to determine exposures to workers mixing this material with a stabilizing agent (portland cement), was performed at a South Louisiana phosphoric acid chemical plant. Measurements of the 226Ra content of the phosphogypsum showed an average of 1.1 +/- 0.3 Bq g-1 (0.7-1.7 Bq g-1). The average measured gross gamma exposure rate on the phosphogypsum pile corresponded to a dose equivalent rate of 0.368 +/- 0.006 mu Sv h-1 (0.32-0.42 mu Sv h-1). Radon daughter concentrations measured on top of the phosphogypsum pile ranged from 0.0006 to 0.001 working levels. An analysis of the airborne 226Ra concentrations showed only background levels.


Assuntos
Sulfato de Cálcio , Indústria Química , Exposição Ocupacional , Ácidos Fosfóricos , Resíduos Radioativos , Eliminação de Resíduos , Bismuto/análise , Chumbo/análise , Polônio/análise , Rádio (Elemento)/análise , Produtos de Decaimento de Radônio
13.
Health Phys ; 63(6): 681-5, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1428889

RESUMO

Scale formation in oilfield piping and equipment has been a problem for petroleum companies. In the past, scale waste from cleaning of piping and equipment has been considered nonhazardous. Naturally occurring radioactive material in the form of 226Ra and, to a lesser degree, 228Ra with their associated decay products have recently been discovered in the scale. Due to the lower abundance and short half-life, 228Ra is not addressed in this paper. 226Ra, an alpha emitter, is a potential internal hazard to workers from the inhalation and ingestion of the dust produced during descaling or pipe cleaning operations. Along with this, a higher-than-normal background gamma exposure rate is seen where the pipe cleaning was routinely done. An evaluation of the radiation hazards associated with a retired pipe cleaning field was performed. Gamma exposure rates, 226Ra concentration, and 226Ra leachability were examined using scale containing soil from the field. Radon emanation from the soil was also determined.


Assuntos
Contaminação de Equipamentos , Exposição Ocupacional , Petróleo , Rádio (Elemento) , Partículas alfa , Raios gama , Humanos , Radônio
14.
Health Phys ; 68(3): 406-10, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7860314

RESUMO

Tank battery sites have historically been used for the initial processing of crude oil which separates water and sediment from the produced oil. Typically, one or more producing wells is connected to a tank battery site consisting of storage and separation tanks. Historical operating practices also included a production holding pit for increased separation of oil, water, and sediment. The sediment remaining in the pit is composed of an oily, viscous material called sludge. Under certain circumstances, this sludge may contain naturally occurring radioactive material. The methodology required for reclamation of the production holding pits consisted of removal of soil and sludge from the pits with controlled land-spreading to achieve biodegradation of the hydrocarbons. The purpose of this study was to perform a radiological characterization on representative tank battery sites that had been reclaimed in the above fashion. The average gamma radiation exposure rates encountered ranged from 2.1-7.2 pC kg-1 s-1. The average concentration of 226Ra for the tank battery sites ranged from 0.5-2.3, 0.5-2.8, and 0.3-3.2 Bq g-1 for soil depths of 0-15, 15-30, and 30-51 cm, respectively. Average radon flux measurements ranged from 29.7-211.8 mBq m-2 s-1. Measurements of the radon emanation coefficient of NORM ranged from 3-7%.


Assuntos
Combustíveis Fósseis , Exposição Ocupacional , Centrais Elétricas , Rádio (Elemento)/análise , Radônio/análise , Raios gama , Humanos , Doses de Radiação , Monitoramento de Radiação/métodos , Estados Unidos , United States Environmental Protection Agency
15.
Health Phys ; 73(5): 794-9, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9378655

RESUMO

A computer code was developed to simulate the bremsstrahlung dose rate distribution patterns produced by the CAMD electron storage ring. These bremsstralung dose rate distributions were measured along the interior surface of the shield walls (short walls perpendicular to the bending magnets) with TLD chips. Electron losses for each specific magnet was determined by running the computer code and varying the electron loss parameters to fit the measured dose rate distributions. It was determined that (1) bending magnet No. 1 (closest to the injection septum) loses 2.7 x 1010 electrons per minute during electron injection. The loss rate for each of the subsequent seven bending magnets during injection varies from about 25% to 33% of this number; (2) the magnet immediately subsequent to the bending magnet loses more electrons than the magnet immediately prior to the bending magnet does; and (3) the computer code may be used to predict potential problems such as misalignment.


Assuntos
Simulação por Computador , Elétrons , Modelos Teóricos , Proteção Radiológica , Síncrotrons , Desenho de Equipamento , Luz , Magnetismo , Fótons
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