Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 175
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Nature ; 596(7870): 80-86, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34349288

RESUMO

Flooding affects more people than any other environmental hazard and hinders sustainable development1,2. Investing in flood adaptation strategies may reduce the loss of life and livelihood caused by floods3. Where and how floods occur and who is exposed are changing as a result of rapid urbanization4, flood mitigation infrastructure5 and increasing settlements in floodplains6. Previous estimates of the global flood-exposed population have been limited by a lack of observational data, relying instead on models, which have high uncertainty3,7-11. Here we use daily satellite imagery at 250-metre resolution to estimate flood extent and population exposure for 913 large flood events from 2000 to 2018. We determine a total inundation area of 2.23 million square kilometres, with 255-290 million people directly affected by floods. We estimate that the total population in locations with satellite-observed inundation grew by 58-86 million from 2000 to 2015. This represents an increase of 20 to 24 per cent in the proportion of the global population exposed to floods, ten times higher than previous estimates7. Climate change projections for 2030 indicate that the proportion of the population exposed to floods will increase further. The high spatial and temporal resolution of the satellite observations will improve our understanding of where floods are changing and how best to adapt. The global flood database generated from these observations will help to improve vulnerability assessments, the accuracy of global and local flood models, the efficacy of adaptation interventions and our understanding of the interactions between landcover change, climate and floods.


Assuntos
Aclimatação , Demografia , Planejamento em Desastres , Inundações/estatística & dados numéricos , Modelos Teóricos , Imagens de Satélites , Bases de Dados como Assunto , Clima Extremo , Humanos , Medição de Risco
2.
Am J Transplant ; 17(4): 944-956, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27801552

RESUMO

T helper 17 (Th17)-dependent autoimmune responses can develop after heart or lung transplantation and are associated with fibro-obliterative forms of chronic rejection; however, the specific self-antigens involved are typically different from those associated with autoimmune disease. To investigate the basis of these responses, we investigated whether removal of regulatory T cells or blockade of function reveals a similar autoantigen bias. We found that Th17 cells specific for collagen type V (Col V), kα1-tubulin, and vimentin were present in healthy adult peripheral blood mononuclear cells, cord blood, and fetal thymus. Using synthetic peptides and recombinant fragments of the Col V triple helical region (α1[V]), we compared Th17 cells from healthy donors with Th17 cells from Col V-reactive heart and lung patients. Although the latter responded well to α1(V) fragments and peptides in an HLA-DR-restricted fashion, Th17 cells from healthy persons responded in an HLA-DR-restricted fashion to fragments but not to peptides. Col V, kα1-tubulin, and vimentin are preferred targets of a highly conserved, hitherto unknown, preexisting Th17 response that is MHC class II restricted. These data suggest that autoimmunity after heart and lung transplantation may result from dysregulation of an intrinsic mechanism controlling airway and vascular homeostasis.


Assuntos
Autoantígenos/imunologia , Colágeno Tipo V/imunologia , Imunidade Celular/imunologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Tubulina (Proteína)/imunologia , Vimentina/imunologia , Adolescente , Adulto , Criança , Feminino , Humanos , Leucócitos Mononucleares , Masculino , Pessoa de Meia-Idade , Adulto Jovem
3.
Am J Transplant ; 14(7): 1512-22, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24866539

RESUMO

IL17-dependent autoimmunity to collagen type V (Col V) has been associated with lung transplant obliterative bronchiolitis. Unlike the T helper 1 (Th1)-dependent immune responses to Tetanus Toxoid (TT), the Th17 response to Col V in lung transplant patients and its Th1/17 variant observed in coronary artery disease patients requires IL-1ß, tumor necrosis factor α and CD14(+) cells. Given the involvement of the P2X7 receptor (P2X7R) in monocyte IL-1ß responses, we investigated its role in Th17-, Th1/17- and Th1-mediated proinflammatory responses. Transfer of antigen-pulsed peripheral blood mononucleated cells (PBMCs) from Col V-reactive patients into SCID mouse footpads along with P2X7R antagonists revealed a selective inhibition of Col V-, but not TT-specific swelling responses. P2X7R inhibitors blocked IL-1ß induction from monocytes, including both Col V-α1 peptide-induced (T-dependent), as well as native Col V-induced (T-independent) responses. Significantly higher P2X7R expression was found on CXCR3(neg) CCR4(+)/6(+) CD4(+) [Th17] versus CXCR3(+)CCR4/6(neg) CD4(+) [Th1] subsets in PBMCs, suggesting that the paradigm of selective dependence on P2X7R might extend beyond Col V autoimmunity. Indeed, P2X7R inhibitors suppressed not only anti-Col V, but also Th1/17-mediated alloimmunity, in a heart transplant patient without affecting anti-viral Epstein-Barr virus responses. These results suggest that agents targeting the P2X7R might effectively treat Th17-related transplant pathologies, while maintaining Th1-immunity to infection.


Assuntos
Transplante de Coração , Imunidade Celular/imunologia , Interleucina-17/imunologia , Transplante de Pulmão , Monócitos/imunologia , Receptores Purinérgicos P2X7/metabolismo , Células Th1/imunologia , Animais , Antineoplásicos/farmacologia , Autoimunidade/imunologia , Colágeno Tipo V/imunologia , Colágeno Tipo V/metabolismo , Citometria de Fluxo , Rejeição de Enxerto/imunologia , Humanos , Hipersensibilidade Tardia , Técnicas Imunoenzimáticas , Interferon gama , Interleucina-17/metabolismo , Camundongos , Camundongos SCID , Monócitos/metabolismo , Monócitos/patologia , Receptores Purinérgicos P2X7/química , Receptores Purinérgicos P2X7/imunologia , Suramina/farmacologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/patologia , Células Th1/metabolismo , Células Th1/patologia
5.
Science ; 230(4726): 663-6, 1985 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-4048951

RESUMO

Intracellular free calcium (Ca2+ i) is thought to be an important second messenger for phagocyte functions. The fluorescent indicator Quin2 was used to measure and visualize [Ca2+]i in human neutrophils during chemotaxis toward, and phagocytosis of, opsonized zymosan. In neutrophils migrating toward zymosan, [Ca2+]i was highest in the lamellipodium. Neutrophils ingesting opsonized zymosan had the highest [Ca2+]i in the pseudopods and periphagosomal cytoplasm. Most of the increase in [Ca2+]i was from extracellular sources. Regional increments in [Ca2+]i are strategically located to modulate such cellular functions as chemotaxis, oxidative activity, and degranulation.


Assuntos
Cálcio/fisiologia , Neutrófilos/fisiologia , Fagocitose , Aminoquinolinas , Quimiotaxia de Leucócito , Humanos , Neutrófilos/metabolismo , Zimosan
6.
J Nutr Health Aging ; 21(10): 180-185, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29300439

RESUMO

BACKGROUND: Sarcopenia is defined as the loss of skeletal muscle mass and function associated with aging. Muscle mass can be reliably and accurately quantified using clinical CT scans but reference measurements are lacking, particularly in healthy US populations. METHODS: Two-phase CT scans from healthy kidney donors (age 18-40) at the University of Michigan between 1999-2010 were utilized. Muscle mass was quantified using two thoracic and two lumbar muscle cross-sectional area (CSA) measures. Indexed measurements were computed as area divided by height-squared. Paired analyses of non-contrast and contrast phases and different Hounsfield Unit (HU) ranges for muscle were conducted to determine their effect on CSA muscle measures. We report the means, standard deviations, and 2SD sarcopenia cutoffs from this population. RESULTS: Healthy population CSA (cm2) cutoffs for N=604 males/females respectively were: 34.7/20.9 (T12 Dorsal Muscle), 91.5/55.9 (T12 Skeletal Muscle), 141.7/91.2 (L3 Skeletal Muscle), 23.5/14.3 (L4 Total Psoas Area), and 23.4/14.3 (L4 Psoas Muscle Area). Height-indexed CSA (cm2/m2) cutoffs for males/females respectively were: 10.9/7.8 (T12 Dorsal Muscle), 28.7/20.6 (T12 Skeletal Muscle), 44.6/34.0 (L3 Skeletal Muscle), 7.5/5.2 (L4 Total Psoas Area), and 7.4/5.2 (L4 Psoas Muscle Area). We confirmed that a mask of -29 to 150 HU is optimal and shows no significant difference between contrast-enhanced and non-contrast CT scan CSA measurements. CONCLUSIONS: We quantified reference values for lumbar and thoracic muscle CSA measures in a healthy US population. We defined the effect of IV contrast and different HU ranges for muscle. Combined, these results facilitate the extraction of clinically valuable data from the large numbers of existing scans performed for medical indications.


Assuntos
Músculo Esquelético/patologia , Músculos Psoas , Sarcopenia , Tomografia Computadorizada por Raios X/normas , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Estudos Retrospectivos , Sarcopenia/complicações , Sarcopenia/patologia
7.
Rev Sci Instrum ; 87(10): 102501, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27802696

RESUMO

This report amplifies and extends prior descriptions of the use of laser Doppler vibrometry (LDV) as a method for assessing cardiovascular activity, on a non-contact basis. A rebreathing task (n = 35 healthy individuals) was used to elicit multiple effects associated with changes in autonomic drive as well as blood gases including hypercapnia. The LDV pulse was obtained from two sites overlying the carotid artery, separated by 40 mm. A robust pulse signal was obtained from both sites, in accord with the well-described changes in carotid diameter over the blood pressure cycle. Emphasis was placed on extracting timing measures from the LDV pulse, which could serve as surrogate measures of pulse wave velocity (PWV) and the associated arterial stiffness. For validation purposes, a standard measure of pulse transit time (PTT) to the radial artery was obtained using a tonometric sensor. Two key measures of timing were extracted from the LDV pulse. One involved the transit time along the 40 mm distance separating the two LDV measurement sites. A second measure involved the timing of a late feature of the LDV pulse contour, which was interpreted as reflection wave latency and thus a measure of round-trip travel time. Both LDV measures agreed with the conventional PTT measure, in disclosing increased PWV during periods of active rebreathing. These results thus provide additional evidence that measures based on the non-contact LDV technique might provide surrogate measures for those obtained using conventional, more obtrusive assessment methods that require attached sensors.


Assuntos
Pressão Sanguínea , Artérias Carótidas/fisiopatologia , Hipercapnia/fisiopatologia , Fluxometria por Laser-Doppler , Análise de Onda de Pulso , Pulso Arterial , Adulto , Feminino , Humanos , Masculino
8.
Circulation ; 104(12 Suppl 1): I92-8, 2001 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-11568037

RESUMO

BACKGROUND: The Queen Elizabeth II Health Sciences Centre uses a weekly peer-review conference of cardiovascular experts to prioritize each surgical case to 1 of 4 queues with the use of standardized criteria of coronary anatomy, stress test result, and symptoms. We examined the hazard of waiting as well as the impact of waiting on surgical outcomes. METHODS AND RESULTS: Analysis was performed for 2102 consecutive patients queued for CABG, aortic valve replacement, or CABG+aortic valve replacement between January 1, 1998, and December 31, 1999. Among 1854 patients undergoing surgery, median waiting times on the respective queues were as follows: in-house urgent group, 8 days; semiurgent A group, 37 days; semiurgent B group, 64 days; and elective group, 113 days. There were 13 deaths (12 cardiac) that occurred during the waiting period (0.7% of the patients). Of the 8.7% patients upgraded to a more urgent queue, 86.1% required hospitalization before surgery. Although female sex was not associated with prolonged waiting time, it was predictive of urgent status (P=0.001). The incidence of postoperative complications was 25.0%, and operative mortality was 2.86%. Both were more frequent among patients undergoing surgery early (P=0.01); however, this difference was attributable to the in-house urgent queue. The median length of stay was 7 days for all patients and was not affected by waiting time. CONCLUSIONS: Death and upgrades while the patients were waiting tended to occur early in the queuing process, and prolonged waiting was not associated with worse surgical outcomes. The cost of reducing waiting times could in part be offset by prevention of hospital admissions among upgraded patients.


Assuntos
Procedimentos Cirúrgicos Cardíacos/normas , Doença das Coronárias/cirurgia , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Avaliação de Processos e Resultados em Cuidados de Saúde , Seleção de Pacientes , Cuidados Pré-Operatórios/métodos , Listas de Espera , Valva Aórtica/cirurgia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/normas , Doença das Coronárias/mortalidade , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/normas , Humanos , Incidência , Tempo de Internação/estatística & dados numéricos , Nova Escócia/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Cuidados Pré-Operatórios/efeitos adversos , Cuidados Pré-Operatórios/economia , Medição de Risco , Fatores Sexuais , Taxa de Sobrevida , Fatores de Tempo
9.
Cell Signal ; 9(1): 53-7, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9067630

RESUMO

Previous studies implicating a role for protein kinase C (PKC) in mediating stimulation of cellular responses by physiological agonists have relied on use of non-specific inhibitors or direct stimulation of PKC by phorbol esters. However, much of this evidence is questionable. Here, we have investigated the effects of a potent and selective PKC inhibitor, Ro 31-8425, on three different responses of human neutrophils stimulated by either a physiological agonist, C5a, or a phorbol ester, PMA. The responses studied were superoxide generation, collagenase secretion and adhesion to endothelial cells. In each case, the PMA-stimulated response was more sensitive to inhibition than the C5a-stimulated response. Even the PMA-stimulated responses differed in their sensitivity to inhibition, with superoxide production being the most sensitive and adhesion at least sensitive. The different sensitivities of the PMA stimulated responses suggest that, although activation of PKC stimulates the responses, either different degrees of activation or different isozymes are required for the different responses. The lower sensitivity of the C5a-stimulated responses in each case suggests that PKC activation, if needed at all, is not rate limiting in these signal transduction pathways. These results emphasize the redundancy in intracellular signal transduction.


Assuntos
Inibidores Enzimáticos/farmacologia , Indóis/farmacologia , Maleimidas/farmacologia , Neutrófilos/efeitos dos fármacos , Proteína Quinase C/antagonistas & inibidores , Transdução de Sinais , Colagenases/metabolismo , Citocalasina B/farmacologia , Glucuronidase/metabolismo , Humanos , Superóxidos/metabolismo
10.
J Leukoc Biol ; 45(5): 389-95, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2540256

RESUMO

Both purified human monocyte interleukin-1 and recombinant interleukin-1 (beta) primed neutrophils for increased superoxide production and chemiluminescence in response to f-met-leu-phe. In addition, purified human monocyte interleukin-1 and recombinant interleukin-1 (beta) altered neutrophil shape. Recombinant interleukin-1 (alpha) used at the same concentration of interleukin-1 (beta) did not prime neutrophils for increased superoxide production after stimulation with f-met-leu-phe. Interleukin-1 expressed by monocytes in response to endotoxin stimulation could act as a modulator of neutrophil function.


Assuntos
Interleucinas/farmacologia , Neutrófilos/efeitos dos fármacos , Superóxidos/biossíntese , Humanos , Técnicas In Vitro , Interleucina-1/farmacologia , Medições Luminescentes , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/citologia , Neutrófilos/metabolismo , Oxirredução/efeitos dos fármacos
11.
Cardiovasc Res ; 51(4): 749-61, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11530108

RESUMO

OBJECTIVE: This study aimed to determine the mode of action of Fas ligand (FasL)/Fas at mediating apoptosis so as to evaluate the potential of FasL in gene therapy for restenosis. METHODS: Passaged human coronary artery smooth muscle (HCASM) cells were infected with recombinant adenoviral vectors expressing murine FasL. Various parameters of FasL expression and apoptosis were measured using FACS, immunofluorescence, calorimetric, and cytotoxicity assays. RESULTS: Most HCASM cells under normal growth conditions expressed Fas and were shown to be susceptible to membrane bound but not soluble FasL. However, some FasL expressing cells survived for up to 7 days. These surviving cells were observed to be spatially distributed and were not in direct physical contact with each other. Upon examination, it was determined that although the majority of the surviving cells expressed FasL, only 30% expressed both Fas and FasL. These cells were capable of inducing apoptosis of target cells and some were also susceptible to FasL expressing cells, provided that the effector and target cells were in close physical contact. FasL/Fas-mediated apoptosis was inhibited by p35, a baculovirus gene that inhibits caspases. Additionally, in contrast to HCASM cells, neither membrane-bound nor soluble FasL induced apoptosis in coronary artery endothelial cells. CONCLUSIONS: FasL expressing HCASM cells do not undergo FasL/Fas mediated "suicide" but kill neighboring cells bearing Fas in a "fratricidal" manner. A small population of HCASM cells expresses no surface Fas. These results imply that HCASM cells transduced in vivo with FasL may serve as "scavengers" and exert a bystander effect on surrounding cells that may be enhanced by co-expression of p35. As FasL-mediated apoptosis occurs in coronary arterial smooth muscle but not endothelial cells, FasL may also offer an advantage over other genes for use in restenosis since the latter may indiscriminately delay re-endothelialization at the sites of gene.


Assuntos
Apoptose/fisiologia , Doença das Coronárias/terapia , Terapia Genética , Glicoproteínas de Membrana/genética , Músculo Liso Vascular/metabolismo , Proteínas Virais , Receptor fas/metabolismo , Adenoviridae/genética , Animais , Proteínas da Membrana Bacteriana Externa/farmacologia , Inibidores de Caspase , Comunicação Celular , Células Cultivadas , Doença das Coronárias/metabolismo , Vasos Coronários , Inibidores Enzimáticos/farmacologia , Proteína Ligante Fas , Expressão Gênica , Vetores Genéticos/administração & dosagem , Humanos , Lipoproteínas/farmacologia , Glicoproteínas de Membrana/metabolismo , Camundongos , Transdução Genética
12.
Endocrinology ; 142(7): 3014-26, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11416023

RESUMO

Uterine artery endothelial cells (UAEC) from pregnant ewes (P-UAEC) demonstrate generally enhanced ability to couple growth factor and G protein-coupled receptors to the ERK-1/2 signaling pathway and stimulate NO production independently of elevated [Ca(2+)]. Herein we investigate the signaling and vasodilator responses to ATP, an agonist that also elevates [Ca(2+)](i) in both NP and P-UAEC, to determine the relative importance of Ca(2+) vs. ERK-1/2 in the activation of eNOS. We observed in both NP-UAEC and P-UAEC that ATP acts through G protein-coupled P(2Y) receptors to activate phospholipase C and dose-dependently elevate [Ca(2+)](i) independently of extracellular Ca(2+). The small reduction in the [Ca(2+)](i) response in NP vs. P-UAEC did not, however, account for the difference in NO production by P-UAEC>>NP-UAEC. ATP had no stimulatory effect on Akt phosphorylation but rapidly stimulated ERK-1/2 phosphorylation in P-UAEC>>NP-UAEC in a manner that correlated with NO production. In both NP- and P-UAEC, both ERK-1/2 and Ca(2+) were absolutely required for eNOS as well as cPLA(2) activation and the Ca(2+) sensitivity of eNOS was enhanced through the cytosolic [Ca(2+)](i) range in P-UAEC>>NP-UAEC. Thus ERK-1/2 may regulate the Ca(2+) sensitivity of eNOS to an even greater extent than is known to occur for cPLA(2).


Assuntos
Cálcio/fisiologia , Endotélio Vascular/fisiologia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Óxido Nítrico Sintase/metabolismo , Fosfolipases A/metabolismo , Prenhez/fisiologia , Útero/irrigação sanguínea , Animais , Artérias/citologia , Artérias/fisiologia , Células Cultivadas , Citosol/enzimologia , Endotélio Vascular/química , Feminino , Óxido Nítrico Sintase Tipo III , Gravidez , Ovinos , Transdução de Sinais/fisiologia
13.
Endocrinology ; 141(3): 1107-17, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10698187

RESUMO

During pregnancy, the uterine vasculature shows a marked increase in vasodilator production [prostacyclin (PGI2) and nitric oxide (NO)] in response to a number of agonists including angiotensin II (AII) and ATP. As a consequence vascular resistance is kept low, and uterine blood flow is maximized to meet the needs of the growing fetus. Studies of the molecular basis underlying this change in control of endothelial NO and PGI2 production have been hampered by the lack of availability of a suitable cell model. To that end we have developed and characterized a new ovine uterine artery endothelial cell (UAEC) culture model derived from nonpregnant (NP) or pregnant (P) ewes. Endothelial cells were isolated from pregnant (120-130 days; n = 6) and nonpregnant (n = 4) ewes and maintained in primary culture. Endothelial cells at passage 4 showed uniform expression of endothelial nitric oxide synthase (eNOS; an endothelial marker) as well as AII type 1 receptor and growth factor receptors and uniform uptake of acetylated low density lipoprotein (a property of endothelial cells not shared by fibroblasts or vascular smooth muscle cells), thus demonstrating cell purity. Expressions of eNOS, cyclooxygenase-1, PGI2 synthase, cytosolic phospholipase A2, AII type 1 receptor, and growth factor receptors are also maintained at passage 4. Mitogenesis is maintained in response to basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), and vascular endothelial growth factor (VEGF) in both NP-UAEC and P-UAEC. The differential production of vasodilators by NP-UAEC and P-UAEC is maintained in a manner similar to that previously reported in vivo. Thus, P-UAEC make NO in response to AII, ATP, bFGF, EGF, and VEGF, whereas NP-UAEC make NO in response to bFGF, EGF, and VEGF only. Similarly, P-UAEC make PGI2 in response to AII, ATP, bFGF, and VEGF, whereas NP-UAEC make PGI2 only in response to ATP and VEGF. As both cytosolic phospholipase A2 and eNOS may be regulated by both Ca2+ and protein kinases, we investigated the effects of these agonists on Ca2+ mobilization and ERK-1/2 phosphorylation. ATP consistently elevates Ca2+ levels in both P-UAEC and NP-UAEC. All other agonists were without acute (0-4 min) effect on Ca2+ in P-UAEC or NP-UAEC. In contrast, all agonists stimulated an acute (10 min) phosphorylation of ERK-1/2 in P-UAEC, whereas only EGF stimulated activation in NP-UAEC. P-UAEC production of PGI2 by agonists of both heptahelical receptors and growth factor receptors correlates closely with ERK-2 phosphorylation alone. For NO, this correlation holds for heptahelical receptor agonists, but additional signaling pathways are also implicated for bFGF and VEGF. In contrast, in NP-UAEC the lack of ERK-2 phosphorylation in response to all agonists other than EGF, and the dissociation between NO or PGI2 production and ERK-2 phosphorylation suggest that alternate pathways play a predominant role.


Assuntos
Comunicação Celular/fisiologia , Endotélio Vascular/metabolismo , Prenhez/fisiologia , Transdução de Sinais/fisiologia , Útero/metabolismo , Vasodilatadores/metabolismo , Angiotensina I/metabolismo , Animais , Western Blotting , Células Cultivadas , Ciclo-Oxigenase 1 , Endotélio Vascular/citologia , Feminino , Imuno-Histoquímica , Isoenzimas/biossíntese , Lipoproteínas LDL/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Mitose/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase Tipo III , Gravidez , Prostaglandina-Endoperóxido Sintases/biossíntese , RNA Mensageiro/biossíntese , Receptores de Angiotensina/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ovinos
14.
Cancer Lett ; 148(1): 87-93, 2000 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-10680597

RESUMO

The presence of an exon 1' sequence in the estrogen receptor alpha (ERalpha) mRNA was detected in different stocks of ER-positive MCF-7 human breast cancer cells by reverse transcriptase polymerase chain reaction (RT-PCR) and ribonuclease protection analysis (RPA), but not by Northern blot analysis. This mRNA, however, was not detectable in ERalpha-positive ZR-75-1 or ERalpha-negative MDA-MB-231 breast cancer cells, suggesting that exon 1' ER mRNA is differentially expressed in some but not all ER-positive cell lines, and then, only at very low levels.


Assuntos
Neoplasias da Mama/genética , Éxons/genética , Expressão Gênica , RNA Mensageiro/genética , Receptores de Estrogênio/genética , Sequência de Bases , Northern Blotting , Neoplasias da Mama/patologia , Clonagem Molecular , Receptor alfa de Estrogênio , Variação Genética/genética , Humanos , Dados de Sequência Molecular , Fases de Leitura Aberta/genética , Regiões Promotoras Genéticas/genética , RNA Mensageiro/isolamento & purificação , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica/genética , Células Tumorais Cultivadas
15.
Cancer Lett ; 113(1-2): 131-9, 1997 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-9065812

RESUMO

Given the important role of the estrogen receptor (ER) in the development and physiology of the breast, it is essential to delineate the mechanisms responsible for its failed expression in some breast tumors. We have cloned and sequenced a portion of the ER upstream regulatory region from the ER-positive MCF-7 and the ER-negative MDA-MB-231 breast cancer cell lines to determine if sequence alterations in this region account for the ER-negative phenotype of some tumors. From this, we identified a number of variations between the sequences, two of which were determined to be associated with a 50% decrease in CAT activity.


Assuntos
Neoplasias da Mama/genética , Receptores de Estrogênio/genética , Sequência de Bases , Neoplasias da Mama/enzimologia , Cloranfenicol O-Acetiltransferase/genética , Cloranfenicol O-Acetiltransferase/metabolismo , Clonagem Molecular , Feminino , Variação Genética , Humanos , Leucócitos , Dados de Sequência Molecular , Sequências Reguladoras de Ácido Nucleico , Homologia de Sequência do Ácido Nucleico , Células Tumorais Cultivadas
16.
Mol Cell Endocrinol ; 158(1-2): 25-36, 1999 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-10630402

RESUMO

The estrogen receptor (ER) serves as a diagnostic marker for the treatment of breast cancer. Patients with ER-positive breast tumors are likely to respond to hormonal therapies, while ER-negative breast cancers are resistant to endocrine therapies. Most ER-negative tumors do not express detectable levels of ER transcript, highlighting the importance of transcriptional regulation. A novel regulatory element which resembles a steroid hormone response element has been identified in the 5'-flanking region of the human ER gene. We observed 3- to 5-fold higher specific binding to this element in nuclear extracts from ER-expressing MCF-7 breast cancer cells compared to ER-negative MDA-MB-231 breast tumor cells. We termed the factor(s) which bind to this cis-element estrogen receptor upstream binding factor-1 (ERUBF-1). In transient transfection assays in MCF-7 cells, the ERUBF-1 binding site elicited a 20-fold increase in luciferase activity over the ER P1, promoter. This enhancer element was significantly more active in the ER-positive MCF-7 cell line compared to the ER-negative MDA-MB-231 cell line. These data indicate that ERUBF-1 plays an important role in the transcriptional regulation of the ER gene in breast cancer.


Assuntos
Elementos Facilitadores Genéticos , Receptores de Estrogênio/genética , Sequência de Bases , Western Blotting , Neoplasias da Mama , Pegada de DNA , DNA de Neoplasias/análise , Feminino , Genes Reporter/genética , Humanos , Luciferases/genética , Luciferases/metabolismo , Dados de Sequência Molecular , Neoplasias Hormônio-Dependentes , Ligação Proteica , Transfecção , Células Tumorais Cultivadas
17.
Am J Med Genet ; 92(5): 336-42, 2000 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-10861663

RESUMO

The purpose of the study was to explore self-concept in women at risk for inheriting the fragile X mutation. Time 1 measures were obtained prior to carrier testing and Time 2 measures were collected approximately 5 months after learning carrier status. The sample consisted of 42 women from 17 families. Measures included the Tennessee Self-Concept Scale (TSCS), the fragile X Visual Analog Scale (VAS), and a structured interview. The TSCS provided a global measure of self-concept and the fragile X VAS and structured interview provided a contextual measure of self related to carrier status. Results indicated that there were no differences initially between carriers and noncarriers and no change from Time 1 to Time 2 on the TSCS. Analysis of the Time 1 fragile X VAS means for the total sample found a reduction in positive feelings about self. Analysis of the Time 2 fragile X VAS found that noncarriers reported improvement in feelings about self, with no change in feelings about self found in the carriers. Responses from the structured interview indicated that the feelings regarding self in the context of genetic testing are not related to global self-concept, but result from concerns regarding the implications of a positive carrier test for themselves and their families. This information highlights areas related to carrier testing that warrant further investigation and may ultimately result in modifications to the genetic counseling.


Assuntos
Síndrome do Cromossomo X Frágil/genética , Triagem de Portadores Genéticos , Adulto , Feminino , Humanos
18.
Am J Med Genet ; 98(1): 37-45, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11426454

RESUMO

This paper reports the results of a longitudinal study of women at-risk to inherit the fragile X mutation. It addresses 1) how upsetting the women perceived their carrier information to be, 2) how serious a problem they perceive fragile X syndrome to be, and 3) descriptions of feelings about the carrier testing process. The study sample consisted of 42 women (20 carriers and 22 noncarriers). There were two measurement times (just prior to carrier testing and after learning actual carrier status). The measures used were a Fragile X Visual Analog Scale and a structured interview. At time 1, being at-risk was reported to be upsetting and fragile X syndrome was perceived to be a serious problem. For the women found to be carriers there was no change from time 1 to time 2 on any of the items. Significant change occurred in the non-carriers. They were significantly less upset at time 2 after receiving the results of their carrier test than at time 1. They also perceived fragile X syndrome to be a more serious problem than they did at time 1 and a more serious problem than the carriers at time 2. Themes found included concerns that carrier status for fragile X syndrome presented a barrier for having healthy biological children and concern for children's and grandchildren's adaptation to their own carrier status. Coping behaviors were activated to manage the emotions related to these concerns. The coping behaviors identified were minimization, acceptance of the possibility of being a carrier, a sense of being able to deal with the outcome of the carrier test, positive comparison, problem solving, and positive interpretation.


Assuntos
Síndrome do Cromossomo X Frágil/psicologia , Testes Genéticos/psicologia , Heterozigoto , Adaptação Psicológica , Adulto , Idoso , Feminino , Síndrome do Cromossomo X Frágil/genética , Humanos , Entrevista Psicológica , Estudos Longitudinais , Pessoa de Meia-Idade , Medição da Dor
19.
Am J Med Genet ; 82(3): 206-11, 1999 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-10215541

RESUMO

Sixty-five parents of individuals affected by fragile X syndrome who attended the National Fragile X Conference in Portland, Oregon (1996), were asked to complete a survey assessing parental level of concern about carrier testing in children at risk for fragile X syndrome. All subjects completed a 15-item paper and pencil Likert response scale measure that was developed specifically for this study. The items included parental rights and duties, psychological adjustment, adaptation, discrimination, harm, childbearing, and interpersonal relationships. The major concern of the parents was that their children have knowledge of their carrier status prior to becoming sexually active and that their children be able to marry informed of their genetic risk. Mothers were significantly more concerned than fathers about raising their children with the knowledge of their carrier status. A sense of parental right to make the decision regarding carrier testing for children was associated with concerns about (1) behavioral or educational problems, (2) knowledge of carrier status prior to sexual activity or marriage, and (3) adjustment of the children to knowledge of their carrier status. As the sample was drawn from a unique population of parents, the results of this survey should be interpreted with caution. The findings of this study suggest a model of parents providing anticipatory guidance for their children to help them adjust to carrier information and for their children to have this knowledge prior to the possibility of reproduction.


Assuntos
Atitude Frente a Saúde , Síndrome do Cromossomo X Frágil/genética , Síndrome do Cromossomo X Frágil/psicologia , Triagem de Portadores Genéticos , Pais/psicologia , Aconselhamento Genético/psicologia , Humanos , Risco , Fatores Sexuais , Inquéritos e Questionários
20.
J Thorac Cardiovasc Surg ; 98(1): 33-6, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2739423

RESUMO

Fourteen patients with isolated stenosis of the left coronary artery ostium underwent vein patch angioplasty. An anterior approach between the aorta and pulmonary artery to expose the left main coronary ostium was used in 12 of 14 patients. There were no deaths, and postoperative angiograms in 13 of the patients showed normal coronary ostial contour with normal runoff. Two perioperative myocardial infarctions were observed. Four of the 14 patients underwent an urgent operation. Isolated coronary ostial stenosis appears to be a distinct clinical entity occurring in younger patients, mostly female, and often with a short clinical course. Unstable pain and hemodynamics are observed. The common pathologic cause of the stenotic lesion is not clear.


Assuntos
Doença das Coronárias/cirurgia , Adulto , Idoso , Angiografia Coronária , Doença das Coronárias/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA