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1.
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
2.
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
3.
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.

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.
Phys Rev Lett ; 100(10): 101101, 2008 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-18352170

RESUMO

The High Resolution Fly's Eye (HiRes) experiment has observed the Greisen-Zatsepin-Kuzmin suppression (called the GZK cutoff) with a statistical significance of five standard deviations. HiRes' measurement of the flux of ultrahigh energy cosmic rays shows a sharp suppression at an energy of 6 x 10(19) eV, consistent with the expected cutoff energy. We observe the ankle of the cosmic-ray energy spectrum as well, at an energy of 4 x 10(18) eV. We describe the experiment, data collection, and analysis and estimate the systematic uncertainties. The results are presented and the calculation of the statistical significance of our observation is described.

6.
Blood ; 98(8): 2403-11, 2001 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11588037

RESUMO

The specific retention of intravenously administered hemopoietic cells within bone marrow is a complex multistep process. Despite recent insights, the molecular mechanics governing this process remain largely undefined. This study explored the influence of beta(2)-integrins on the homing to bone marrow and repopulation kinetics of progenitor cells. Both antifunctional antibodies and genetically deficient cells were used. In addition, triple selectin-deficient mice were used as recipients of either deficient (selectin or beta(2)) or normal cells in homing experiments. The homing patterns of either beta(2) null or selectin null cells into normal or selectin-deficient recipients were similar to those of normal cells given to normal recipients. Furthermore, spleen colony-forming units and the early bone marrow repopulating activity for the first 2 weeks after transplantation were not significantly different from those of control cells. These data are in contrast to the importance of beta(2)-integrin and selectins in the adhesion/migration cascade of mature leukocytes. The special bone marrow flow hemodynamics may account for these differences. Although early deaths after transplantation can be seen in recipients deficient in CD18 and selectin, these are attributed to septic complications rather than homing defects. However, when beta(2)- or selectin-null donor cells are treated with anti-alpha(4) antibodies before their transplantation to normal or selectin-deficient recipients, a dramatic inhibition of homing (>90%) was found. The data suggest that the alpha(4)beta(1)/vascular cell adhesion molecule-1 pathway alone is capable of providing effective capture of cells within the bone marrow, but if its function is compromised, the synergistic contribution of other pathways, that is, beta(2)-integrins or selectins, is uncovered.


Assuntos
Medula Óssea/fisiologia , Antígenos CD18/fisiologia , Moléculas de Adesão Celular/fisiologia , Transplante de Células-Tronco Hematopoéticas , Integrinas/fisiologia , Receptores de Retorno de Linfócitos/fisiologia , Selectinas/fisiologia , Animais , Células da Medula Óssea/citologia , Transplante de Medula Óssea/fisiologia , Antígenos CD18/genética , Ensaio de Unidades Formadoras de Colônias , Genótipo , Integrina alfa4beta1 , Contagem de Leucócitos , Camundongos , Camundongos Knockout , Proteção Radiológica , Taxa de Sobrevida , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/fisiologia
8.
Blood ; 97(5): 1282-8, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11222371

RESUMO

The hierarchy of cytoadhesion molecules involved in hematopoietic/stem progenitor cell mobilization has not yet been delineated. Previous studies have suggested an important role for alpha4beta1 integrin in this process. To test whether mobilization involves dynamic interactions of alpha4beta1 with other integrins on hematopoietic cells, especially the beta2 integrins, mice and primates were treated with anti-beta1 or anti-beta2 antibodies alone or in combination. A single injection of anti-alpha4beta1 antibody elicited reproducible mobilization in contrast to other antibodies, and 3 injections yielded higher mobilization efficiency than each of the other antibodies. When the anti-beta2 (anti-CD11a or anti-CD18) or anti-alpha5/beta1 integrin antibody was combined with anti-alpha4, an augmentation in mobilization was seen that was either additive or synergistic, depending on the potency of the antibody used. Synergy between anti-alpha4 and anti-CD18 (beta(2)) antibody blockade was seen in primates and confirmed in anti-alpha4-treated CD18-deficient mice. In the latter, there was a 49-fold increase in mobilization with anti-alpha4, much higher than in littermate control animals, in CD18 hypomorphic mice, or in other strains of mice tested. Data from both the antibody blockade and gene-targeted mice suggest that the cooperativity of alpha4beta1 with beta2 integrins becomes evident when they are concurrently inhibited. It is unclear whether this cooperativity is exerted at the stage of reversible adhesion versus migration, and enhancement of and whether the 2 integrins work in a sequential or parallel manner. Whatever the mechanism, the data provide a novel example of beta1 and beta2 integrin crosstalk in stem/progenitor cell mobilization.


Assuntos
Antígenos CD18/farmacologia , Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/efeitos dos fármacos , Integrina beta1/farmacologia , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacologia , Células da Medula Óssea/citologia , Antígenos CD18/genética , Antígenos CD18/imunologia , Citocinas/sangue , Citocinas/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Células-Tronco Hematopoéticas/citologia , Integrina alfa4beta1 , Integrina beta1/imunologia , Integrinas/imunologia , Macaca , Masculino , Camundongos , Camundongos Knockout , Receptores de Retorno de Linfócitos/imunologia
9.
Blood ; 96(4): 1267-73, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10942367

RESUMO

Systemic mastocytosis is a disease of mast cell proliferation that may be associated with hematologic disorders. There are no features on examination that allow the diagnosis of systemic disease, and mast cell-derived mediators, which may be elevated in urine or blood, may also be elevated in individuals with severe allergic disorders. Thus, the diagnosis usually depends on results of bone marrow biopsy. To facilitate evaluation, surrogate markers of the extent and severity of the disease are needed. Because of the association of mastocytosis with hematologic disease, plasma levels were measured for soluble KIT (sKIT) and soluble interleukin-2 receptor alpha chain (sCD25), which are known to be cleaved in part from the mast cell surface and are elevated in some hematologic malignancies. Results revealed that levels of both soluble receptors are increased in systemic mastocytosis. Median plasma sKIT concentrations as expressed by AU/mL (1 AU = 1.4 ng/mL) were as follows: controls, 176 (n = 60); urticaria pigmentosa without systemic involvement, 194 (n = 8); systemic indolent mastocytosis, 511 (n = 30); systemic mastocytosis with an associated hematologic disorder, 1320 (n = 7); aggressive mastocytosis, 3390 (n = 3). Plasma sCD25 levels were elevated in systemic mastocytosis; the highest levels were associated with extensive bone marrow involvement. Levels of sKIT correlated with total tryptase levels, sCD25 levels, and bone marrow pathology. These results demonstrate that sKIT and sCD25 are useful surrogate markers of disease severity in patients with mastocytosis and should aid in diagnosis, in the selection of those needing a bone marrow biopsy, and in the documentation of disease progression. (Blood. 2000;96:1267-1273)


Assuntos
Medula Óssea/patologia , Mastocitose/sangue , Mastocitose/patologia , Proteínas Proto-Oncogênicas c-kit/sangue , Receptores de Interleucina-2/sangue , Adolescente , Adulto , Idoso , Biomarcadores , Humanos , Pessoa de Meia-Idade , Prognóstico
10.
J Am Pharm Assoc (Wash) ; 40(2): 174-80, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10730021

RESUMO

OBJECTIVE: To assess factors associated with participation in pharmaceutical care and the benefits of participation--in terms of amount of information about medications, administration of medications, and awareness of side effects. DESIGN: Quasi-experimental design, with a control group. Medication Survey, administered 6 months after pharmaceutical care intervention to participants, refusers, and controls. Logistic regression analyses. SETTING: Three staff clinic pharmacies and three contract clinic pharmacies affiliated with a health maintenance organization (HMO). PATIENTS AND OTHER PARTICIPANTS: Patients with chronic health conditions (asthma, chronic obstructive pulmonary disease, or heart disease) enrolled at six intervention sites, identified through the HMO's electronic pharmacy database. Control sample with the same chronic health conditions, without access to pharmaceutical care (n = 210 participants, 162 refusers, and 368 controls; overall adjusted response rate = 72%). INTERVENTION: Pharmaceutical care, in the form of a comprehensive drug therapy management program. MAIN OUTCOME MEASURES: Predictors of participation, amount of information about medications, use of reminder methods, and awareness of side effects. RESULTS: The following variables were significantly associated with the probability of participating in pharmaceutical care (P < .05): number of medications, employment, income, health status, education, and living situation. Participants were more likely than controls to say they received "a lot of information" from their pharmacist about all aspects of medications (odds ratio [OR], 1.75 to 2.68). Participants were more likely to report leaving their medication container in a visible place and using two or more reminder methods (OR, 1.87 to 1.48). There were no significant differences in the probability of missing doses. Participants were more likely to report experiencing "symptoms or problems" associated with prescription medications (OR, 1.81). CONCLUSION: Pharmaceutical care appears to increase the information given to patients about medications, promote more effective self-administration of medications by encouraging patients to use systematic reminders, and increase awareness of medication side effects.


Assuntos
Doença Crônica/tratamento farmacológico , Educação de Pacientes como Assunto , Satisfação do Paciente , Assistência Farmacêutica/organização & administração , Escolaridade , Feminino , Sistemas Pré-Pagos de Saúde , Humanos , Renda , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Pesquisa
11.
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
12.
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
13.
J Allergy Clin Immunol ; 104(4 Pt 1): 811-9, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10518826

RESUMO

BACKGROUND: Both basophils and T cells are known to secrete IL-4 and IL-13 after activation with either nonspecific stimuli or specific antigen, but the relative contribution of these 2 cell types to overall cytokine production is unclear. OBJECTIVES: To further characterize basophil cytokine production and compare it with that of T cells, we examined the frequency of IL-4- and IL-13-producing basophils and T cells in human PBMCs by means of flow cytometry after activation in allergic asthmatic and normal subjects. METHODS: PBMCs obtained from whole blood after Percoll gradient were activated with specific antigen or ionomycin and fixed. PBMCs were made permeable; stained with antibodies to IgE, CD3, and either IL-4 or IL-13; and analyzed by means of flow cytometry. RESULTS: Preformed cytokines were not detected in unactivated basophils. After ionomycin activation, 60% to 90% of basophils from both control and allergic asthmatic subjects expressed IL-4 and IL-13. Specific antigen induced cytokine expression by 10% to 20% of basophils from the asthmatic group only. After specific antigen activation, basophils accounted for 4 times more IL-4-producing cells than did T cells. IL-4 and IL-13 production at 2 hours was exclusively from basophils. After allergen activation, CD40 ligand was upregulated on a subset of peripheral blood basophils. CONCLUSIONS: These data demonstrate that basophils are the predominant peripheral blood cells that express IL-4 and IL-13 in the first 6 hours after antigen activation and strengthen the putative role of basophils both in IgE production and in the generation of allergic inflammation.


Assuntos
Asma/sangue , Basófilos/metabolismo , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Linfócitos T/metabolismo , Adulto , Alérgenos/farmacologia , Basófilos/efeitos dos fármacos , Ligante de CD40 , Glicoproteínas/imunologia , Humanos , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Testes Cutâneos , Linfócitos T/efeitos dos fármacos
14.
Blood ; 94(7): 2333-42, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10498605

RESUMO

Human mast cells are known to arise from a CD34(+)/c-kit(+) progenitor cell population that also gives rise to neutrophils, eosinophils, basophils, and monocytes. To further characterize cells within the CD34(+)/c-kit(+) population that yield mast cells, this progenitor was additionally sorted for CD13, a myeloid marker known to appear early on rodent mast cells and cultured human mast cells, but not expressed or expressed at low levels on human tissue mast cells; and cultured in recombinant human (rh) stem cell factor (rhSCF), rh interleukin-3 (rhIL-3; first week only), and rhIL-6. Initial sorts revealed that although the majority of cells in culture arose from the CD34(+)/c-kit(+)/CD13(-) cell population, mast cells arose from a CD34(+)/c-kit(+)/CD13(+) progenitor cell that also gave rise to a population of monocytes. Sequential sorting confirmed that CD34(+)/c-kit(+)/CD13(+) cells in CD34(+)/c-kit(+)/CD13(-) sorts gave rise to the few mast cells observed in CD13(-) sorted cells. CD34(+)/c-kit(+)/CD13(+) cells plated as single cells in the presence of various cytokine combinations gave rise to pure mast cell, monocyte, or mixed mast cell/monocyte progeny. Addition of either rh granulocyte-macrophage colony-stimulating factor (rhGM-CSF) or rhIL-5 to the CD34(+)/c-kit(+)/CD13(+) progenitor cell population cultured in rhSCF, rhIL-3, and rhIL-6 did increase the number of total cells cultured and in the case of rhIL-5, did increase total mast cell numbers. Neither rhGM-CSF or rhIL-5 led to additional cell populations, ie, even with the addition of rhGM-CSF or rhIL-5, only mast cells and monocytes grew from CD34(+)/c-kit(+)/CD13(+) cells. Thus, human mast cells and a population of monocytes arise from precursor cells that express CD34, c-kit, and CD13; and within which, are mast cell, monocyte, and mast/monocyte (bipotential) precursors.


Assuntos
Antígenos CD34/biossíntese , Antígenos CD13/genética , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/fisiologia , Mastócitos/citologia , Proteínas Proto-Oncogênicas c-kit/biossíntese , Antígenos CD/biossíntese , Células da Medula Óssea/citologia , Antígenos CD13/análise , Antígenos CD13/biossíntese , Células Cultivadas , Células Clonais , Células-Tronco Hematopoéticas/efeitos dos fármacos , Liberação de Histamina , Humanos , Separação Imunomagnética/métodos , Interleucina-3/farmacologia , Interleucina-6/farmacologia , Mastócitos/efeitos dos fármacos , Mastócitos/fisiologia , Proteínas Recombinantes/farmacologia , Fator de Células-Tronco/farmacologia
16.
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
18.
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
19.
Blood ; 88(7): 2517-30, 1996 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-8839844

RESUMO

Retinoic acid (RA)-induced maturation mediated by the retinoic acid receptor alpha (RAR alpha) has been implicated in myeloid development. We have used differential hybridization analysis of a cDNA library constructed from the murine RA-inducible MPRO promyelocyte cell line to identify immediate-early genes induced by RA during granulocytic differentiation. E3, one of nine sequences identified, was upregulated in an immediate-early manner, with transcript levels peaking after 60 minutes exposure to RA. E3 transcripts were RA-inducible in HL60 cells, but not in an RA-resistant subclone, HL60R, that harbors a mutated RAR alpha gene. However, when HL60R cells were transduced with a functional copy of the RAR alpha gene, RA induced a 10-fold increase in E3 mRNA levels. E3 transcripts are present in the myeloid, B-lymphoid, and erythroid lineages, absent in nonhematopoietic cells, and encode a highly hydrophobic, potentially phosphorylated polypeptide of unknown function with significant homology to a putative protein expressed in myeloid cells. The murine E3 promoter harbors a single bipartite retinoic acid response element which in transient transfection assays conferred RA sensitivity. These results indicate that E3 is a hematopoietic-specific gene that is an immediate target for the activated RAR alpha during myelopoiesis.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Genes Precoces , Células-Tronco Hematopoéticas/efeitos dos fármacos , Proteínas Imediatamente Precoces/genética , Receptores do Ácido Retinoico/fisiologia , Tretinoína/farmacologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Diferenciação Celular , Células Cultivadas , Sequência Consenso , DNA Complementar/genética , Granulócitos/citologia , Células HL-60/efeitos dos fármacos , Células HL-60/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Humanos , Proteínas Imediatamente Precoces/biossíntese , Proteínas Imediatamente Precoces/fisiologia , Leucemia Promielocítica Aguda/patologia , Proteínas de Membrana , Camundongos , Dados de Sequência Molecular , Neoplasias/patologia , Fosforilação , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Receptores do Ácido Retinoico/genética , Sequências Reguladoras de Ácido Nucleico , Receptor alfa de Ácido Retinoico , Homologia de Sequência do Ácido Nucleico , Transfecção
20.
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
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