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1.
Philos Trans A Math Phys Eng Sci ; 379(2195): 20190543, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33641467

RESUMO

Projections of precipitation extremes in simulations with global climate models are very uncertain in the tropics, in part because of the use of parameterizations of deep convection and model deficiencies in simulating convective organization. Here, we analyse precipitation extremes in high-resolution simulations that are run without a convective parameterization on a quasi-global aquaplanet. The frequency distributions of precipitation rates and precipitation cluster sizes in the tropics of a control simulation are similar to the observed distributions. In response to climate warming, 3 h precipitation extremes increase at rates of up to [Formula: see text] in the tropics because of a combination of positive thermodynamic and dynamic contributions. The dynamic contribution at different latitudes is connected to the vertical structure of warming using a moist static stability. When the precipitation rates are first averaged to a daily timescale and coarse-grained to a typical global climate-model resolution prior to calculating the precipitation extremes, the response of the precipitation extremes to warming becomes more similar to what was found previously in coarse-resolution aquaplanet studies. However, the simulations studied here do not exhibit the high rates of increase of tropical precipitation extremes found in projections with some global climate models. This article is part of a discussion meeting issue 'Intensification of short-duration rainfall extremes and implications for flash flood risks'.

2.
Spinal Cord ; 54(9): 750-3, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26927296

RESUMO

OBJECTIVE: To measure body mass index (BMI) and ambulation changes for a morbidly obese, 47-year-old man with chronic motor-incomplete tetraplegia after gastric sleeve surgery. DESIGN/METHOD: A morbidly obese man, BMI=44 kg m(-)(2), with chronic C5 AIS D tetraplegia underwent elective gastric sleeve surgery. Assessment of BMI and function via the 6-minute walk test (6MWT), 10-meter walk test (10MWT) and ambulation parameters (CIR Systems/GAITRite, Franklin, NJ, USA) was performed preoperatively and at 12, 24, 36 and 52 weeks postoperatively, and additionally after 3 weeks of both a prescribed coached (3 × /week facility based) and a non-coached (3 × /week home based) walking program initiated at 52 weeks. A step activity monitor assessed daily ambulation preoperatively, prior to and during the third and sixth week of the walking program. RESULTS: Results included a 34.3% peak BMI decrease at 52 weeks post surgery and a peak increase in 6MWT distance of 58% at 52 weeks post surgery, 10MWT preferred speed of 56% at 55 weeks and step activity monitor of 82% at 58 weeks post surgery. At 58 weeks, gait data demonstrated a decrease in double limb stance of 38% and decrease in base of support of 72%. CONCLUSION/CLINICAL RELEVANCE: This empirical case assessment of BMI and functional mobility before and after gastric sleeve surgery may encourage further investigation into mobility and general health effects post gastric procedures for people with chronic motor-incomplete spinal cord injury.


Assuntos
Cirurgia Bariátrica/métodos , Transtornos Neurológicos da Marcha/etiologia , Obesidade/etiologia , Obesidade/cirurgia , Quadriplegia/complicações , Redução de Peso/fisiologia , Índice de Massa Corporal , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Quadriplegia/cirurgia , Caminhada
3.
Ann Oncol ; 26(7): 1340-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26003169

RESUMO

BACKGROUND: Chromosomal instability (CIN) has been shown to be associated with drug resistance and poor clinical outcome in several cancer types. However, in oestrogen receptor (ER)-negative breast cancer we have previously demonstrated that extreme CIN is associated with improved clinical outcome, consistent with a negative impact of CIN on tumour fitness and growth. The aim of this current study was to validate this finding using previously defined CIN thresholds in a much larger prospective cohort from a randomised, controlled, clinical trial. PATIENTS AND METHODS: As a surrogate measurement of CIN, dual centromeric fluorescence in situ hybridisation was performed for both chromosomes 2 and 15 on 1173 tumours from the breast cancer TACT trial (CRUK01/001). Each tumour was scored manually and the mean percentage of cells deviating from the modal centromere number was used to define four CIN groups (MCD1-4), where tumours in the MCD4 group were defined as having extreme CIN. RESULTS: In a multivariate analysis of disease-free survival, with a median follow-up of 91 months, increasing CIN was associated with improved outcome in patients with ER-negative cancer (P trend = 0.03). A similar pattern was seen in ER-negative/HER2-negative cancers (Ptrend = 0.007). CONCLUSIONS: This prospective validation cohort study further substantiated the association between extreme CIN and improved outcome in ER-negative breast cancers. Identifying such patients with extreme CIN may help distinguish good from poor prognostic groups, and therefore support treatment and risk stratification in this aggressive breast cancer subtype.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Instabilidade Cromossômica , Receptores de Estrogênio/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antraciclinas/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Receptor ErbB-2/metabolismo , Receptores de Progesterona/metabolismo , Taxa de Sobrevida , Taxoides/administração & dosagem , Adulto Jovem
4.
Br J Cancer ; 110(4): 1053-7, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24366306

RESUMO

BACKGROUND: Invasive lobular breast cancer (ILC) and lobular carcinoma in situ (LCIS) are characterised by loss of E-cadherin expression. However germline CDH1 mutations are rare in cases of ILC with no family history of hereditary diffuse gastric cancer (HDGC) and have not been described in women with LCIS. METHODS: We screened the CDH1 gene in 50 cases of bilateral LCIS/ILC using Sanger sequencing and MLPA. RESULTS: Sanger sequencing revealed four pathogenic germline mutations, including a novel splicing mutation (c.48+1G>A). The remaining three (c.1465insC, c.1942G>T, c.2398delC) have been previously described. All four cases had bilateral LCIS +/- ILC and no family history of gastric cancer. CONCLUSION: CDH1 germline mutations have not been previously described in women with LCIS. We have shown that germline CDH1 mutations are associated with early onset of bilateral LCIS with or without ILC in women without a family history of gastric cancer. CDH1 mutation screening should be considered in women with early onset of bilateral LCIS/ILC with no family history of HDGC.


Assuntos
Neoplasias da Mama/genética , Caderinas/genética , Carcinoma in Situ/genética , Carcinoma Lobular/genética , Antígenos CD , Sequência de Bases , Neoplasias da Mama/patologia , Carcinoma Lobular/patologia , Feminino , Mutação em Linhagem Germinativa/genética , Humanos , Pessoa de Meia-Idade , Análise de Sequência de DNA
5.
Spinal Cord ; 52(4): 287-91, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24534779

RESUMO

STUDY DESIGN: Prospective assessment as part of initial evaluations for randomized-controlled trial participation. OBJECTIVES: To determine the test-retest reliability of peak VO2 testing during both robotically assisted body weight supported treadmill training (RABWSTT) and arm cycle ergometry and to assess whether a relationship exists between these two measurements in individuals with chronic motor incomplete spinal cord injury (CMISCI). METHODS: Twenty-one participants with CMISCI enrolled in a 3- month, RABWSTT randomized-controlled trial. As part of their baseline assessments, individuals underwent VO2 peak assessments twice on separate days during both RABWSTT and arm cycle ergometry using a metabolic cart. RESULTS: Peak oxygen consumption measured at baseline correlated significantly between repeated tests in the RABWSTT (r=0.96, P<0.01) and the arm ergometer (r=0.95, P<0.01). A Pearson correlation (r=0.87, P<0.01) existed between the peak VO2 measurements obtained using RABWSTT and arm ergometry, although Bland-Altman analysis suggested a more limited relationship with a bias of 1.1 favoring arm ergometry. This relationship was stronger for individuals with tetraplegia than for people with paraplegia. CONCLUSION/CLINICAL RELEVANCE: Determination of VO2 peak during both RABWSTT and arm ergometry in individuals with CMISCI is highly reproducible. Furthermore, a moderate correlation exists between peak VO2 measured during RABWSTT and arm cycle ergometry in this population for individuals with tetraplegia. This correlation offers implications for future cardiovascular testing of individuals with CMISCI, as two reliable peak VO2 measurement techniques are possible.


Assuntos
Teste de Esforço/métodos , Exercício Físico/fisiologia , Consumo de Oxigênio/fisiologia , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/reabilitação , Adulto , Idoso , Braço/fisiopatologia , Doença Crônica , Feminino , Humanos , Extremidade Inferior/fisiopatologia , Masculino , Pessoa de Meia-Idade , Paraplegia/diagnóstico , Paraplegia/etiologia , Paraplegia/fisiopatologia , Paraplegia/reabilitação , Estudos Prospectivos , Quadriplegia/diagnóstico , Quadriplegia/etiologia , Quadriplegia/fisiopatologia , Quadriplegia/reabilitação , Ensaios Clínicos Controlados Aleatórios como Assunto , Reprodutibilidade dos Testes , Robótica , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/diagnóstico
6.
Opt Lett ; 38(22): 4686-9, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24322106

RESUMO

We present a pulsed fiber laser system with average power up to 265 W, pulse energy up to 10.6 mJ, pulse duration adjustable in the range 500 ps-500 ns, repetition rate fully controllable from single-shot operation up to 1 MHz, and the ability to control peak power independently of pulse energy. The system has a compact, all-spliced construction. Such a versatile laser will have wide applications in materials processing.

7.
Nat Med ; 5(9): 1071-5, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10470088

RESUMO

APC is often cited as a prime example of a tumor suppressor gene. Truncating germline and somatic mutations (or, infrequently, allelic loss) occur in tumors in FAP (familial adenomatous polyposis). Most sporadic colorectal cancers also have two APC mutations. Clues from attenuated polyposis, missense germline variants with mild disease and the somatic mutation cluster region (codons 1,250-1,450) indicate, however, that APC mutations might not result in simple loss of protein function. We have found that FAP patients with germline APC mutations within a small region (codons 1,194-1,392 at most) mainly show allelic loss in their colorectal adenomas, in contrast to other FAP patients, whose 'second hits' tend to occur by truncating mutations in the mutation cluster region. Our results indicate that different APC mutations provide cells with different selective advantages, with mutations close to codon 1,300 providing the greatest advantage. Allelic loss is selected strongly in cells with one mutation near codon 1,300. A different germline-somatic APC mutation association exists in FAP desmoids. APC is not, therefore, a classical tumor suppressor. Our findings also indicate a new mechanism for disease severity: if a broader spectrum of mutations is selected in tumors, the somatic mutation rate is effectively higher and more tumors grow.


Assuntos
Polipose Adenomatosa do Colo/genética , Neoplasias Colorretais/genética , Genes APC/genética , Mutação em Linhagem Germinativa/genética , Modelos Genéticos , Mutação/genética , Adenoma/genética , Adenoma/patologia , Polipose Adenomatosa do Colo/patologia , Alelos , Sequência de Bases , Códon/genética , Neoplasias Colorretais/patologia , Análise Mutacional de DNA , Éxons/genética , Saúde da Família , Fibromatose Agressiva/genética , Fibromatose Agressiva/patologia , Mutação da Fase de Leitura/genética , Deleção de Genes , Frequência do Gene , Humanos
8.
Ir Med J ; 102(9): 294-5, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19902650

RESUMO

We report the case of a 35 year patient from Nigeria who presented with fever and splenomegaly. The initial diagnosis was Salmonellosis. However, relapsing symptoms lead to a re-evaluation and ultimately a diagnosis of Multicentric Castleman's Disease (MCD). There is no gold standard treatment but our patient responded to Rituximab and Highly active anti-retroviral therapy. MCD is a rare, aggressive disease that should be considered in a HIV positive patient presenting with fever and significant lymphadenopathy.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Hiperplasia do Linfonodo Gigante/diagnóstico , Herpesvirus Humano 8 , Fatores Imunológicos/uso terapêutico , Adulto , Anti-Infecciosos/uso terapêutico , Anticorpos Monoclonais Murinos , Hiperplasia do Linfonodo Gigante/tratamento farmacológico , Hiperplasia do Linfonodo Gigante/patologia , Hiperplasia do Linfonodo Gigante/cirurgia , Ciprofloxacina/uso terapêutico , Humanos , Masculino , Rituximab , Esplenomegalia
9.
Method Innov ; 12(1)2019.
Artigo em Inglês | MEDLINE | ID: mdl-35465616

RESUMO

Our objective was to model process variation of Emergency Medical Service teams responding to simulated pediatric emergencies and determine if sequence alignment distinguishes performance quality. We performed a retrospective process analysis by watching and coding activities in videos from standardized simulations of 42 Emergency Medical Service teams. Teams were classified into high- or low-performing groups based on the Clinical Teamwork Scale™. Activities were coded according to resuscitation tasks, performer, and times. We used ClustalG to align task sequences within and between groups, and measured similarity. Teams within and between performance levels had an average sequence similarity of 52 ± 7% and 50 ± 7%. Teams performed clinically appropriate tasks that varied in prioritization, for example, performing compressions or connecting the EKG monitor early. There was no statistical difference in gross similarity between groups but specific differences in prioritization may have had clinically meaningful implications. Alignment could improve by accounting for task duration and concurrency.

10.
Oncogene ; 25(49): 6544-53, 2006 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-16702952

RESUMO

We analysed chromosome 16q in 106 breast cancers using tiling-path array-comparative genomic hybridization (aCGH). About 80% of ductal cancers (IDCs) and all lobular cancers (ILCs) lost at least part of 16q. Grade I (GI) IDCs and ILCs often lost the whole chromosome arm. Grade II (GII) and grade III (GIII) IDCs showed less frequent whole-arm loss, but often had complex changes, typically small regions of gain together with larger regions of loss. The boundaries of gains/losses tended to cluster, common sites being 54.5-55.5 Mb and 57.4-58.8 Mb. Overall, the peak frequency of loss (83% cancers) occurred at 61.9-62.9 Mb. We also found several 'minimal' regions of loss/gain. However, no mutations in candidate genes (TRADD, CDH5, CDH8 and CDH11) were detected. Cluster analysis based on copy number changes identified a large group of cancers that had lost most of 16q, and two smaller groups (one with few changes, one with a tendency to show copy number gain). Although all morphological types occurred in each cluster group, IDCs (especially GII/GIII) were relatively overrepresented in the smaller groups. Cluster groups were not independently associated with survival. Use of tiling-path aCGH prompted re-evaluation of the hypothetical pathways of breast carcinogenesis. ILCs have the simplest changes on 16q and probably diverge from the IDC lineage close to the stage of 16q loss. Higher-grade IDCs probably develop from low-grade lesions in most cases, but there remains evidence that some GII/GIII IDCs arise without a GI precursor.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/genética , Cromossomos Humanos Par 16 , Invasividade Neoplásica/genética , Hibridização de Ácido Nucleico/métodos , Análise Serial de Tecidos/métodos , Aberrações Cromossômicas , Quebra Cromossômica , Análise por Conglomerados , DNA de Neoplasias , Amplificação de Genes , Deleção de Genes , Ligação Genética , Humanos , Perda de Heterozigosidade , Modelos Estatísticos , Estadiamento de Neoplasias
11.
Oncogenesis ; 6(10): e388, 2017 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-28991260

RESUMO

Triple negative breast cancer (TNBC) is an aggressive subtype with relatively poor clinical outcomes and limited treatment options. Chemotherapy, while killing cancer cells, can result in the generation of highly chemoresistant therapeutic induced senescent (TIS) cells that potentially form stem cell niches resulting in metastases. Intriguingly, senescent cells release significantly more extracellular vesicles (EVs) than non-senescent cells. Our aim was to profile EVs harvested from TIS TNBC cells compared with control cells to identify a potential mechanism by which TIS TNBC cells maintain survival in the face of chemotherapy. TIS was induced and confirmed in Cal51 TNBC cells using the chemotherapeutic paclitaxel (PTX) (Taxol). Mass spectrometry (MS) analysis of EVs harvested from TIS compared with control Cal51 cells was performed using Ingenuity Pathway Analysis and InnateDB programs. We demonstrate that TIS Cal51 cells treated with 75 nM PTX for 7 days became senescent (senescence-associated ß-galactosidase (SA-ß-Gal) positive, Ki67-negative, increased p21 and p16, G2/M cell cycle arrest) and released significantly more EVs (P=0.0002) and exosomes (P=0.0007) than non-senescent control cells. Moreover, TIS cells displayed an increased expression of the multidrug resistance protein 1/p-glycoprotein. MS analysis demonstrated that EVs derived from senescent Cal51 cells contained 142 proteins with a significant increased fold change compared with control EVs. Key proteins included ATPases, annexins, tubulins, integrins, Rabs and insoluble senescence-associated secretory phenotype (SASP) factors. A fluorescent analogue of PTX (Flutax-2) allowed appreciation of the removal of chemotherapy in EVs from senescent cells. Treatment of TIS cells with the exosome biogenesis inhibitor GW4869 resulted in reduced SA-ß-Gal staining (P=0.04). In summary, this study demonstrates that TIS cells release significantly more EVs compared with control cells, containing chemotherapy and key proteins involved in cell proliferation, ATP depletion, apoptosis and the SASP. These findings may partially explain why cancer senescent cells remain viable despite chemotherapeutic challenge.

12.
Cancer Res ; 59(7): 1433-6, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10197608

RESUMO

How does breast cancer progress? There is evidence both to support (S. W. Duffy et al., Br. J. Cancer, 64: 1133-1138, 1991; R. Rajakariar et al., Br. J. Cancer, 71: 150-154, 1995) and refute (M. Hakama et al., Lancet, 345: 221-224, 1995; R. R. Millis et al., Eur. J. Cancer, 34: 548-553, 1998) the hypothesis of dedifferentiation; the theory that as breast cancers grow they evolve from well differentiated (grade I) to poorly differentiated (grade III) tumors. We provide evidence to support the view that the majority of grade I tumors do not progress to grade III tumors. Comparative genomic hybridization was used to screen entire genomes of a large sample (40 grade I and 50 grade III) of invasive ductal breast carcinomas, stratified by grade. We found distinct genetic differences between grade I and grade III tumors. Significantly, we found that 65% of grade I tumors lost the long arm of chromosome 16 compared with only 16% of grade III tumors. This pattern of loss leads us to conclude that the majority of grade I tumors do not progress to grade III tumors. These findings have important implications because they suggest that different breast tumor grades may have distinct molecular origins, pathogenesis, and behavior and, therefore, potentially present distinct molecular targets for research and treatment.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Aberrações Cromossômicas , Cromossomos Humanos Par 16 , Feminino , Humanos , Hibridização de Ácido Nucleico
13.
Leukemia ; 30(5): 1005-17, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26710887

RESUMO

The prognosis for patients multiple myeloma (MM) has improved substantially over the past decade with the development of new, more effective chemotherapeutic agents and regimens that possess a high level of anti-tumor activity. In spite of this important progress, however, nearly all MM patients ultimately relapse, even those who experience a complete response to initial therapy. Management of relapsed MM thus represents a vital aspect of the overall care for patients with MM and a critical area of ongoing scientific and clinical research. This comprehensive manuscript from the International Myeloma Working Group provides detailed recommendations on management of relapsed disease, with sections dedicated to diagnostic evaluation, determinants of therapy, and general approach to patients with specific disease characteristics. In addition, the manuscript provides a summary of evidence from clinical trials that have significantly impacted the field, including those evaluating conventional dose therapies, as well as both autologous and allogeneic stem cell transplantation. Specific recommendations are offered for management of first and second relapse, relapsed and refractory disease, and both autologous and allogeneic transplant. Finally, perspective is provided regarding new agents and promising directions in management of relapsed MM.


Assuntos
Mieloma Múltiplo , Guias de Prática Clínica como Assunto , Antineoplásicos/uso terapêutico , Gerenciamento Clínico , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Mieloma Múltiplo/terapia , Recidiva , Terapia de Salvação/métodos
14.
Arch Intern Med ; 143(9): 1719-25, 1983 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6615094

RESUMO

One hundred six postmyocardial infarction subjects who either achieved a mean work load of less than seven mets on treadmill testing, who were rated as anxious and/or depressed, or who met both criteria, participated in a controlled study comparing the rehabilitation effectiveness of exercise therapy and group counseling. Each intervention lasted 12 weeks. Follow-up evaluations were scheduled at three months, six months and one year. Exercise substantially increased mean work capacity, decreased fatigue, lessened anxiety and depression, and promoted independence and sociability. Counseling substantially reduced depression and promoted a sense of friendliness, and decreased interpersonal friction as well as greater independence and sociability. The control group reported no substantial change on any measured factor. Neither counseling nor exercise had an effect on mortality though subjects in the exercise group reported fewer major cardiovascular sequelae.


Assuntos
Terapia por Exercício , Infarto do Miocárdio/reabilitação , Psicoterapia de Grupo , Idoso , Ansiedade/reabilitação , Depressão/reabilitação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Arch Intern Med ; 142(13): 2269-74, 1982 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7149870

RESUMO

As part of the National Exercise and Heart Disease Project, 223 postcoronary men, aged 30 to 64, were randomly assigned to moderate exercise or control groups. Levels of total plasma cholesterol, high- and low-density lipoprotein (HDL and LDL) cholesterol, and triglycerides were measured. At baseline, alcohol intake, weight, and skin-fold thickness but not treadmill work capacity correlated with triglyceride or HDL cholesterol levels. After one year, no clinically important change in lipid levels was observed in either group. Using multiple regression analysis of the combined groups, changes in several independent variables, including work capacity change, were not predictive of changes in lipid levels. Thus, changes in levels of fitness and/or regular exercise did not substantially influence HDL cholesterol or other lipid levels.


Assuntos
Lipoproteínas/sangue , Esforço Físico , Adulto , Colesterol/sangue , Humanos , Lipídeos/sangue , Lipoproteínas HDL/sangue , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Risco
16.
Gene ; 200(1-2): 177-83, 1997 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-9373153

RESUMO

We have mapped the human ORFX gene to chromosome 9q34 and determined its complete gene structure. Comparison with RING3, the human MHC-linked homologue on 6p21.3, shows the two gene structures to be highly conserved but with an approximate threefold expansion in the ORFX introns. RING3 and ORFX are found to be ubiquitously expressed in human adult and foetal tissues. Evidence suggests that the two genes may have arisen from an ancient duplication in a common ancestral chromosome.


Assuntos
Cromossomos Humanos Par 6 , Cromossomos Humanos Par 9 , Complexo Principal de Histocompatibilidade , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Serina-Treonina Quinases/genética , Proteínas de Ligação a RNA/biossíntese , Proteínas de Ligação a RNA/genética , Transcrição Gênica , Adulto , Sequência de Bases , Sítios de Ligação , Células Cultivadas , Mapeamento Cromossômico , Sequência Consenso , Sequência Conservada , Feto , Ligação Genética , Humanos , Hibridização in Situ Fluorescente , Íntrons , NF-kappa B/metabolismo , Fatores de Transcrição
17.
Int J Radiat Oncol Biol Phys ; 46(4): 1019-24, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10705025

RESUMO

PURPOSE: Long-term preclinical studies using continuous, low-dose-rate vascular brachytherapy with (32)P beta-emitting stents have yielded largely disappointing results. In contrast, a shorter half-life, higher dose-rate (90)Y beta-emitting stent more closely mimics the delivery dose rate characteristics of clinically effective beta- and gamma-wire and balloon brachytherapy devices. We evaluated the dose response characteristics of a (90)Y beta-emitting stent in the canine coronary injury model and hypothesized that this device would reduce neointimal formation. METHODS: Seventy-seven (90)Y beta-emitting coronary stents (15 mm BXTM, 3.0- and 3.5-mm diameter) were implanted in 26 normal dogs (20-25 kg) using a randomized, blinded study design. Stent activity included nonradioactive controls (n = 24), 4.5 microCi (n = 15), 8 microCi (n = 12), 16 microCi (n = 18), and 32 microCi (n = 8). Histologic endpoints were assessed at 3 months. RESULTS: Luminal stenosis and neointimal area were similar in control stents and low-activity (4.5 and 8 microCi) (90)Y stents. Higher activity stents (16 and 32 microCi) were associated with significant adverse effects. Frequent total occlusions (5 of 18 stents, 28%; p = 0.008) and a 40% increase in neointimal area (p = 0.024 vs. control) occurred in the 16 microCi group. Incomplete neointimal healing and a trend for reduced neointimal cell density were evident only in the 16- and 32-microCi group. CONCLUSION: Despite unique characteristics (2.7 day half-life and a higher dose rate) of (90)Y beta-emitting coronary stents, they have an adverse effect on neointimal formation, including frequent total occlusions at high activity levels. Incomplete healing, present 90 days (33 half-lives) after stent placement, indicates prolonged recovery from radiation injury.


Assuntos
Braquiterapia/métodos , Vasos Coronários/efeitos da radiação , Stents , Túnica Íntima/efeitos da radiação , Radioisótopos de Ítrio/uso terapêutico , Animais , Braquiterapia/instrumentação , Vasos Coronários/lesões , Cães , Relação Dose-Resposta à Radiação , Método Duplo-Cego , Meia-Vida , Radioisótopos de Fósforo/uso terapêutico , Distribuição Aleatória , Stents/efeitos adversos , Túnica Íntima/lesões
18.
Am J Cardiol ; 85(4): 416-20, 2000 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10728943

RESUMO

The relation of maximal exercise systolic pressure to physical conditioning and to mortality was determined in 641 men with > or =1 myocardial infarctions. Each performed a standardized multistage exercise test before randomized assignment either to an exercise group or a control group and at scheduled periodic intervals over 3 years. This study compares 123 men with maximal exercise systolic pressures (MESP) of < or =140 mm Hg with 518 men whose maximal exercise systolic pressure was > or =140 mm Hg. At baseline, the 2 groups were comparable for age, entry time since the occurrence of the qualifying cardiac event, and reported use of antihypertensive medications. Men with low MESP used more beta blockers, had lower systolic pressure measurements at rest and by definition at maximal exercise, and lower work capacity than men with higher levels of MESP. Men with low MESP experienced: (1) no reduction in mortality with exercise conditioning (p<0.86), and (2) a significantly higher mortality rate over 3 years (p<0.003) compared with men with higher levels of MESP. The relation of a low MESP to mortality persisted: (1) whether MESP or work capacity increased from the baseline exercise test to the last performed exercise test, and (2) whether it was measured at low (<6 METs) or high (> or =6 METs) levels of work capacity. We conclude that low maximal exercise systolic blood pressure is a predictor of mortality and is associated with an ineffective training response in men with myocardial infarction.


Assuntos
Pressão Sanguínea/fisiologia , Terapia por Exercício , Exercício Físico/fisiologia , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Causas de Morte , Tolerância ao Exercício , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/reabilitação , Prognóstico , Taxa de Sobrevida , Sístole
19.
Am J Cardiol ; 86(12): 1398-400, A6, 2000 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11113426

RESUMO

This randomized, double-blind trial found that tissue plasminogen activator activity increased and plasminogen activator inhibitor-1 activity decreased significantly more with exercise during placebo treatment than during treatment with beta blockade. These results suggest that beta blockade blunts the fibrinolytic response to maximal exercise.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Antifibrinolíticos/farmacologia , Esforço Físico/fisiologia , Propranolol/farmacologia , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Adulto , Análise de Variância , Atenolol/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Interações Medicamentosas , Fibrinolíticos/sangue , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Placebos , Inibidor 1 de Ativador de Plasminogênio/sangue , Descanso/fisiologia , Inibidores de Serina Proteinase/sangue , Ativador de Plasminogênio Tecidual/sangue
20.
Br J Pharmacol ; 94(1): 212-8, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-2900036

RESUMO

1. The isolated perfused lung of the ferret was used to study the effects of dopamine receptor agonists and antagonists. Under constant flow, a fall in pulmonary artery pressure reflects a vasodilator response. Since tone is normally low, agonists were given during hypoxic pulmonary vasoconstriction to enable detection of dilator responses. 2. Vasodilator responses were produced by bolus doses of dopamine over the range 0.1 to 5.0 micrograms kg-1, and by the selective DA1 agonist SK&F 38393 (1-phenyl-7,8-dihydroxy-2,3,4,5-tetrahydro-1H-3-benzazepine hydrochloride). 3. The dopamine response was blocked by low doses of the selective DA1-antagonist SCH23390 (R-(+)-8-chloro-2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3-benzazepine-7- ol maleate), and by sulpiride. 4. The vasodilator response to the relatively selective DA2-agonist N,N-di-n-propyl dopamine occurred only at high dose and was incompletely blocked by the selective DA2 antagonist domperidone at a cumulative dose of 10 mg kg-1. 5. Thus dopamine receptors of the DA1 type may mediate vasodilatation in the ferret pulmonary circulation, but no evidence was obtained for the existence of DA2-receptors.


Assuntos
Carnívoros/fisiologia , Dopamina/farmacologia , Furões/fisiologia , Circulação Pulmonar/efeitos dos fármacos , Vasodilatadores , Animais , Anti-Hipertensivos/farmacologia , Antipsicóticos/farmacologia , Benzazepinas/farmacologia , Dopamina/análogos & derivados , Relação Dose-Resposta a Droga , Técnicas In Vitro , Masculino , Sulpirida/farmacologia
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