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1.
Int J Behav Nutr Phys Act ; 16(1): 66, 2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31420000

RESUMO

BACKGROUND: Physical activity has beneficial effects on the health of cancer survivors. We aimed to investigate accelerometer-assessed physical activity and sedentary time in cancer survivors, and describe activity profiles. Additionally, we identify demographic and clinical correlates of physical activity, sedentary time and activity profiles. METHODS: Accelerometer, questionnaire and clinical data from eight studies conducted in four countries (n = 1447) were pooled. We calculated sedentary time and time spent in physical activity at various intensities using Freedson cut-points. We used latent profile analysis to identify activity profiles, and multilevel linear regression analyses to identify demographic and clinical variables associated with accelerometer-assessed moderate to vigorous physical activity (MVPA), sedentary time, the highly active and highly sedentary profile, adjusting for confounders identified using a directed acyclic graph. RESULTS: Participants spent on average 26 min (3%) in MVPA and 568 min (66%) sedentary per day. We identified six activity profiles. Older participants, smokers and participants with obesity had significantly lower MVPA and higher sedentary time. Furthermore, men had significantly higher MVPA and sedentary time than women and participants who reported less fatigue had higher MVPA time. The highly active profile included survivors with high education level and normal body mass index. Haematological cancer survivors were less likely to have a highly active profile compared to breast cancer survivors. The highly sedentary profile included older participants, males, participants who were not married, obese, smokers, and those < 12 months after diagnosis. CONCLUSIONS: Cancer survivors engage in few minutes of MVPA and spend a large proportion of their day sedentary. Correlates of MVPA, sedentary time and activity profiles can be used to identify cancer survivors at risk for a sedentary and inactive lifestyle.


Assuntos
Sobreviventes de Câncer/estatística & dados numéricos , Exercício Físico , Comportamento Sedentário , Acelerometria , Estudos de Coortes , Feminino , Monitores de Aptidão Física , Humanos , Masculino
2.
Breast Cancer Res Treat ; 166(2): 367-381, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28803384

RESUMO

PURPOSE: With only 5-10% of breast cancer cases attributed to genetic inheritance, prevention efforts have focused on modifiable risk factors. Physical activity plays a role in reducing breast cancer risk; however, the interaction between physical activity and other modifiable risk factors, such as obesity, has received little attention. METHODS: A systematic review and meta-analysis was conducted of studies examining the relationship between physical activity and breast cancer and how it may be modified by body mass index (BMI). RESULTS: A total of 29 papers were included: 18 were cohort and 11 were case-control studies. Overall, a significant reduction in the relative risk of breast cancer was found in postmenopausal women with high versus low levels of physical activity for women with a BMI <25 kg/m2 (RR 0.85, 95% CI 0.79, 0.92) and ≥25 kg/m2 (RR 0.87, 95% CI 0.81, 0.93) but not ≥30 kg/m2 (RR: 0.93, 95% CI 0.76, 1.13). Physical activity was not associated with a significant reduction in risk of breast cancer in premenopausal women in any BMI group. CONCLUSION: The results of this meta-analysis suggest that physical activity is associated with a larger breast cancer risk reduction among women who are normal weight or overweight than among women who are obese. Since the included studies used diverse methods for assessment of physical activity and categories of BMI, results should be interpreted with caution and additional work is needed.


Assuntos
Neoplasias da Mama/epidemiologia , Obesidade/complicações , Neoplasias da Mama/prevenção & controle , Estudos de Coortes , Exercício Físico , Feminino , Humanos , Pós-Menopausa , Pré-Menopausa
3.
Br J Cancer ; 109(3): 814-22, 2013 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-23787918

RESUMO

BACKGROUND: Aside from tumour stage and treatment, little is known about potential factors that may influence survival in colorectal cancer patients. The aim of this study was to investigate the associations between physical activity, obesity and smoking and disease-specific and overall mortality after a colorectal cancer diagnosis. METHODS: A cohort of 879 colorectal cancer patients, diagnosed in Western Australia between 2005 and 2007, were followed up to 30 June 2012. Cox's regression models were used to estimate the hazard ratios (HR) for colorectal cancer-specific and overall mortality associated with self-reported pre-diagnosis physical activity, body mass index (BMI) and smoking. RESULTS: Significantly lower overall and colorectal cancer-specific mortality was seen in females who reported any level of recent physical activity than in females reporting no activity. The colorectal cancer-specific mortality HR for increasing levels of physical activity in females were 0.34 (95% CI=0.15, 0.75), 0.37 (95% CI=0.17, 0.81) and 0.41 (95% CI=0.18, 0.90). Overweight and obese women had almost twice the risk of dying from any cause or colorectal cancer compared with women of normal weight. Females who were current smokers had worse overall and colorectal cancer-specific mortality than never smokers (overall HR=2.64, 95% CI=1.18, 5.93; colorectal cancer-specific HR=2.70, 95% CI=1.16, 6.29). No significant associations were found in males. CONCLUSION: Physical activity, BMI and smoking may influence survival after a diagnosis of colorectal cancer, with more pronounced results found for females than for males.


Assuntos
Neoplasias Colorretais/mortalidade , Estilo de Vida , Idoso , Índice de Massa Corporal , Estudos de Casos e Controles , Estudos de Coortes , Neoplasias Colorretais/diagnóstico , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Fumar/epidemiologia , Austrália Ocidental/epidemiologia
4.
Br J Cancer ; 109(9): 2472-80, 2013 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-24022188

RESUMO

BACKGROUND: Research on the possible association between shiftwork and breast cancer is complicated because there are many different shiftwork factors, which might be involved including: light at night, phase shift, sleep disruption and changes in lifestyle factors while on shiftwork (diet, physical activity, alcohol intake and low sun exposure). METHODS: We conducted a population-based case-control study in Western Australia from 2009 to 2011 with 1205 incident breast cancer cases and 1789 frequency age-matched controls. A self-administered questionnaire was used to collect demographic, reproductive, and lifestyle factors and lifetime occupational history and a telephone interview was used to obtain further details about the shiftwork factors listed above. RESULTS: A small increase in risk was suggested for those ever doing the graveyard shift (work between midnight and 0500 hours) and breast cancer (odds ratio (OR)=1.16, 95% confidence interval (CI)=0.97-1.39). For phase shift, we found a 22% increase in breast cancer risk (OR=1.22, 95% CI=1.01-1.47) with a statistically significant dose-response relationship (P=0.04). For the other shiftwork factors, risks were marginally elevated and not statistically significant. CONCLUSION: We found some evidence that some of the factors involved in shiftwork may be associated with breast cancer but the ORs were low and there were inconsistencies in duration and dose-response relationships.


Assuntos
Neoplasias da Mama/epidemiologia , Tolerância ao Trabalho Programado , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/etiologia , Estudos de Casos e Controles , Feminino , Humanos , Estilo de Vida , Pessoa de Meia-Idade , Risco , Fatores de Risco , Inquéritos e Questionários , Austrália Ocidental/epidemiologia , Adulto Jovem
5.
NPJ Quantum Mater ; 8(1): 60, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38666239

RESUMO

FeSe1-xSx remains one of the most enigmatic systems of Fe-based superconductors. While much is known about the orthorhombic parent compound, FeSe, the tetragonal samples, FeSe1-xSx with x > 0.17, remain relatively unexplored. Here, we provide an in-depth investigation of the electronic states of tetragonal FeSe0.81S0.19, using scanning tunneling microscopy and spectroscopy (STM/S) measurements, supported by angle-resolved photoemission spectroscopy (ARPES) and theoretical modeling. We analyze modulations of the local density of states (LDOS) near and away from Fe vacancy defects separately and identify quasiparticle interference (QPI) signals originating from multiple regions of the Brillouin zone, including the bands at the zone corners. We also observe that QPI signals coexist with a much stronger LDOS modulation for states near the Fermi level whose period is independent of energy. Our measurements further reveal that this strong pattern appears in the STS measurements as short range stripe patterns that are locally two-fold symmetric. Since these stripe patterns coexist with four-fold symmetric QPI around Fe-vacancies, the origin of their local two-fold symmetry must be distinct from that of nematic states in orthorhombic samples. We explore several aspects related to the stripes, such as the role of S and Fe-vacancy defects, and whether they can be explained by QPI. We consider the possibility that the observed stripe patterns may represent incipient charge order correlations, similar to those observed in the cuprates.

6.
Science ; 376(6595): 860-864, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35587968

RESUMO

Superconductivity and charge density waves (CDWs) are competitive, yet coexisting, orders in cuprate superconductors. To understand their microscopic interdependence, a probe capable of discerning their interaction on its natural length and time scale is necessary. We use ultrafast resonant soft x-ray scattering to track the transient evolution of CDW correlations in YBa2Cu3O6+x after the quench of superconductivity by an infrared laser pulse. We observe a nonthermal response of the CDW order characterized by a near doubling of the correlation length within ≈1 picosecond of the superconducting quench. Our results are consistent with a model in which the interaction between superconductivity and CDWs manifests inhomogeneously through disruption of spatial coherence, with superconductivity playing the dominant role in stabilizing CDW topological defects, such as discommensurations.

7.
J Exp Med ; 176(4): 1197-201, 1992 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-1402661

RESUMO

The human immunodeficiency virus (HIV) Rev protein is essential for viral structural protein expression (Gag, Pol, and Env) and, hence, for viral replication. In transient transfection assays, mutant forms of Rev have been identified that inhibit wild-type Rev activity and therefore suppress viral replication. To determine whether such transdominant Rev proteins could provide long-term protection against HIV infection without affecting T cell function, T leukemia cell lines were stably transduced with a retroviral vector encoding a transdominant mutant of the Rev protein, M10. While all the M10-expressing cell lines remained infectable by HIV-1, these same cells failed to support a productive replication cycle when infected with a cloned isolate of HIV-1. In addition, two out of three M10-expressing CEM clones were also resistant to highly productive infection by a heterogeneous HIV-1 pool. Expression of M10 did not affect induction of HIV transcription mediated by the kappa B regulatory element or Tat. Importantly, constitutive expression of Rev M10 did not alter the secretion of interleukin 2 in response to mitogen stimulation of EL-4 and Jurkat cells. The inhibition of HIV infection in cells stably expressing a transdominant Rev protein, in the absence of any deleterious effect on T cell function, suggests that such a strategy could provide a therapeutic effect in the T lymphocytes of acquired immunodeficiency syndrome patients.


Assuntos
Produtos do Gene rev/metabolismo , HIV-1/fisiologia , Linfócitos T/fisiologia , Replicação Viral , Células Clonais , Produtos do Gene rev/genética , HIV-1/genética , Humanos , Interleucina-2/biossíntese , Ativação Linfocitária , NF-kappa B/metabolismo , Linfócitos T/microbiologia , Transcrição Gênica , Transfecção , Produtos do Gene rev do Vírus da Imunodeficiência Humana
8.
J Exp Med ; 176(6): 1703-18, 1992 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-1460427

RESUMO

Human immunodeficiency virus (HIV) infection of brain macrophages and astroglial proliferation are central features of HIV-induced central nervous system (CNS) disorders. These observations suggest that glial cellular interactions participate in disease. In an experimental system to examine this process, we found that cocultures of HIV-infected monocytes and astroglia release high levels of cytokines and arachidonate metabolites leading to neuronotoxicity. HIV-1ADA-infected monocytes cocultured with human glia (astrocytoma, neuroglia, and primary human astrocytes) synthesized tumor necrosis factor (TNF-alpha) and interleukin 1 beta (IL-1 beta) as assayed by coupled reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay, and biological activity. The cytokine induction was selective, cell specific, and associated with induction of arachidonic acid metabolites. TNF-beta, IL-1 alpha, IL-6, interferon alpha (IFN-alpha), and IFN-gamma were not produced. Leukotriene B4, leukotriene D4, lipoxin A4, and platelet-activating factor were detected in large amounts after high-performance liquid chromatography separation and correlated with cytokine activity. Specific inhibitors of the arachidonic cascade markedly diminished the cytokine response suggesting regulatory relationships between these factors. Cocultures of HIV-infected monocytes and neuroblastoma or endothelial cells, or HIV-infected monocyte fluids, sucrose gradient-concentrated viral particles, and paraformaldehyde-fixed or freeze-thawed HIV-infected monocytes placed onto astroglia failed to induce cytokines and neuronotoxins. This demonstrated that viable monocyte-astroglia interactions were required for the cell reactions. The addition of actinomycin D or cycloheximide to the HIV-infected monocytes before coculture reduced, > 2.5-fold, the levels of TNF-alpha. These results, taken together, suggest that the neuronotoxicity associated with HIV central nervous system disorders is mediated, in part, through cytokines and arachidonic acid metabolites, produced during cell-to-cell interactions between HIV-infected brain macrophages and astrocytes.


Assuntos
Ácido Araquidônico/metabolismo , Astrócitos/fisiologia , Córtex Cerebral/fisiologia , Citocinas/genética , Citocinas/metabolismo , Dexametasona/farmacologia , Infecções por HIV/fisiopatologia , HIV/fisiologia , Macrófagos/fisiologia , Monócitos/fisiologia , Animais , Elementos Antissenso (Genética) , Astrócitos/efeitos dos fármacos , Sequência de Bases , Neoplasias Encefálicas , Comunicação Celular , Divisão Celular , Células Cultivadas , Córtex Cerebral/citologia , Eicosanoides/isolamento & purificação , Eicosanoides/metabolismo , Feto , HIV/genética , Infecções por HIV/patologia , Humanos , Lipoxigenase/metabolismo , Macrófagos/efeitos dos fármacos , Dados de Sequência Molecular , Neurônios/citologia , Oligodesoxirribonucleotídeos , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , RNA Mensageiro/metabolismo , RNA Viral/genética , RNA Viral/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Células Tumorais Cultivadas
10.
Science ; 253(5015): 71-4, 1991 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-1905842

RESUMO

Cells of the monocyte-macrophage lineage are targets for human immunodeficiency virus-1 (HIV-1) infection in vivo. However, many laboratory strains of HIV-1 that efficiently infect transformed T cell lines replicate poorly in macrophages. A 20-amino acid sequence from the macrophage-tropic BaL isolate of HIV-1 was sufficient to confer macrophage tropism on HTLV-IIIB, a T cell line--tropic isolate. This small sequence element is in the V3 loop, the envelope domain that is the principal neutralizing determinant of HIV-1. Thus, the V3 loop not only serves as a target of the host immune response but is also pivotal in determining HIV-1 tissue tropism.


Assuntos
Movimento Celular/genética , HIV-1/fisiologia , Proteínas do Envelope Viral/genética , Sequência de Aminoácidos , Animais , Quimera , Genes env/fisiologia , HIV-1/genética , Haplorrinos , Dados de Sequência Molecular , Mutação , Provírus , Mapeamento por Restrição , Homologia de Sequência do Ácido Nucleico
11.
Science ; 257(5069): 535-7, 1992 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-1636088

RESUMO

Laboratory isolates of human immunodeficiency virus type-1 (HIV-1) such as HTLV-IIIB are generally T cell line-tropic and highly sensitive to neutralization by soluble CD4 (sCD4), a potential antiviral agent that is undergoing clinical trial. However, many primary HIV-1 isolates are macrophage-tropic and sCD4-resistant. Envelope V3 loop sequences derived from primary HIV-1 isolates were sufficient to confer on HTLV-IIIB not only the tissue tropism but also the degree of sCD4 neutralization resistance characteristic of their HIV-1 strains of origin. Single amino acid changes in the V3 loop enhanced sCD4 resistance by up to tenfold. These observations suggest that the tissue tropism and sCD4 neutralization sensitivity of HIV-1 isolates are regulated by similar mechanisms.


Assuntos
Antígenos CD4/imunologia , Produtos do Gene gag/imunologia , Proteína gp120 do Envelope de HIV/imunologia , HIV-1/imunologia , Subpopulações de Linfócitos T/imunologia , Sequência de Aminoácidos , Animais , Linhagem Celular , Células Cultivadas , HIV-1/isolamento & purificação , Humanos , Cinética , Dados de Sequência Molecular , Testes de Neutralização , Provírus/imunologia , Transfecção , Vírion/imunologia
12.
J Phys Chem A ; 113(19): 5598-601, 2009 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-19371052

RESUMO

Theoretical calculations based on time-dependent density functional theory are used to characterize the electronic absorption spectrum of a heteroleptic Ti-alkoxide molecule, (OPy)(2)Ti(TAP)(2) [OPy = pyridine carbinoxide, TAP = 2,4,6 tris(dimethylamino)phenoxide] under investigation as a photosensitive precursor for use in optically initiated solution synthesis of the metal oxide. Computational results support the assignment of UV absorption features observed in solid-state precursor films to key intrinsic ground-state transitions that involve ligand-to-metal charge transfer and pi-pi* transitions within the cyclic ligand moieties present. The nature of electron density redistribution associated with these transitions provides early insight into the excitation wavelength dependence of photostructural modification previously observed in this precursor system.

13.
Ir Med J ; 102(5): 149-52, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19623811

RESUMO

Many patients with newly diagnosed breast cancer undergo multiple staging investigations. We aimed to assess the use and yield of baseline diagnostic imaging in early-stage breast cancer. A review of all patients diagnosed with breast cancer over five years at a single institution was carried out. 781 patients were included. At diagnosis 266 (34%) patients underwent a bone scan, which showed metastases in 42 (15.8%), of whom 26 (61.9%) were symptomatic with pain. Only two asymptomatic patients had incidental skeletal metastases detected at an estimated cost of euro 50,850 per case. 261 (33.4%) patients underwent hepatic ultrasonography, which showed metastases in 23 (8.8%), of whom 19 (82.6%) had abnormal liver blood tests. Only two patients had incidental hepatic metastases detected at an estimated cost of euro 29,400 per case. The routine use of these imaging modalities to detect metastases in asymptomatic early-stage breast cancer patients is not justified.


Assuntos
Neoplasias da Mama/economia , Alanina Transaminase , Biomarcadores , Osso e Ossos/diagnóstico por imagem , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Diagnóstico por Imagem/economia , Feminino , Humanos , Irlanda , Fígado/diagnóstico por imagem , Testes de Função Hepática , Estadiamento de Neoplasias , Cintilografia , Fatores de Tempo , Ultrassonografia
14.
J Clin Invest ; 97(3): 806-13, 1996 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-8609238

RESUMO

Signal transduction pathways shared by different autocrine growth factors may provide an efficient approach to accomplish clinically significant control of lung cancer growth. In this study, we demonstrate that two autocrine growth factors activate 5-lipoxygenase action of the arachidonic acid metabolic pathway in lung cancer cell lines. Both growth factors increased the production of 5(S)-hydrooxyeicosa-6E,8Z,11Z,14Z-tetraeno ic acid (5-HETE), a major early 5-lipoxygenase metabolic product. Exogenously added 5-HETE stimulated lung cancer cell growth in vitro. Inhibition of 5-lipoxygenase metabolism by selective antagonists resulted in significant growth reduction for a number of lung cancer cell lines. Primary clinical specimens and lung cancer cell lines express the message for the 5-lipoxygenase enzymes responsible for the generation of active metabolites. In vivo evaluation demonstrated that interruption of 5-lipoxygenase signaling resulted in enhanced levels of programmed cell death. These findings demonstrate that 5-lipoxygenase activation is involved with growth factor-mediated growth stimulation for lung cancer cell lines. Pharmacological intervention with lipoxygenase inhibitors may be an important new clinical strategy to regulate growth factor-dependent stages of lung carcinogenesis.


Assuntos
Araquidonato 5-Lipoxigenase/biossíntese , Carcinoma de Células Pequenas/metabolismo , Substâncias de Crescimento/farmacologia , Neoplasias Pulmonares/metabolismo , Transdução de Sinais , Proteínas Ativadoras de 5-Lipoxigenase , Animais , Araquidonato 5-Lipoxigenase/genética , Ácido Araquidônico/antagonistas & inibidores , Ácido Araquidônico/metabolismo , Sequência de Bases , Carcinoma de Células Pequenas/tratamento farmacológico , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Divisão Celular/efeitos dos fármacos , Peptídeo Liberador de Gastrina , Inibidores de Lipoxigenase/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Masoprocol/uso terapêutico , Proteínas de Membrana/biossíntese , Proteínas de Membrana/genética , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Peptídeos/farmacologia , RNA Mensageiro/análise , Somatomedinas/farmacologia
15.
Ir Med J ; 100(1): 327-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17380921

RESUMO

In the Irish Prison service prison is not deemed suitable for babes. Rarely are mothers separated from their children in Ireland as they get temporary release renewed weekly to keep her at home with her baby. The governor explained the system of the prison which I detail below. The women's prison is now known as the Dochas Centre meaning hope, named so by the women themselves. We found that 14 babies lived in the centre with their mothers in the last 4 years. Their length of stay ranged from 2 days to 3 months. Of the 14 babies in prison, five were born to women who were pregnant on admission and the other nine brought their babies with them. Six women are separated from their children, in total 24, due to her incarceration. The implications are that a formal system is needed to plan the baby's admission, stay and discharge with formal links with HSE health and child protection systems where necessary. The HSE and the Irish prison's service are looking at further amalgamation or integration of health care into the prison system.


Assuntos
Cuidado do Lactente/legislação & jurisprudência , Relações Mãe-Filho , Prisioneiros/psicologia , Prisões/normas , Serviços de Saúde Comunitária , Feminino , Humanos , Lactente , Cuidado do Lactente/normas , Recém-Nascido , Irlanda , Masculino
16.
Endocrinology ; 122(3): 967-75, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3277840

RESUMO

Incubation of human placenta membranes with low concentrations (0.1-0.2 mM) of dithiothreitol (DTT) increased insulin binding approximately 1.4-fold, while 10 mM DTT completely inhibited insulin binding. In contrast, treatment of rat adipocyte membranes with 0.5-2.0 mM DTT increased tracer insulin binding 3- to 6-fold, while higher levels of DTT (10 mM) also fully inhibited insulin binding. Scatchard analysis of insulin binding revealed that DTT treatment of adipocyte membranes resulted in an increase in both the high and low affinity dissociation constants. Purification of adipocyte insulin receptors by wheat germ agglutinin-Sepharose chromatography, followed by insulin-agarose affinity chromatography, resulted in loss of DTT stimulation of insulin binding. Comparison of insulin receptors purified from rat adipocytes or human placenta membranes revealed no significant differences in the DTT sensitivities of insulin binding or protein kinase activities. These data suggest that the functional properties of the rat adipocyte insulin receptor are modified by its membrane environment compared to those of insulin receptors in placenta membranes or purified insulin receptors in detergent solution.


Assuntos
Tecido Adiposo/metabolismo , Placenta/metabolismo , Receptor de Insulina/metabolismo , Tecido Adiposo/efeitos dos fármacos , Animais , Ligação Competitiva , Membrana Celular/metabolismo , Cromatografia de Afinidade , Ditiotreitol/farmacologia , Eletroforese em Gel de Poliacrilamida , Feminino , Glutationa/farmacologia , Humanos , Insulina/análogos & derivados , Insulina/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Masculino , Placenta/efeitos dos fármacos , Gravidez , Ratos , Receptor de Insulina/efeitos dos fármacos , Receptor de Insulina/isolamento & purificação
17.
Gene ; 117(2): 243-7, 1992 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-1639271

RESUMO

A 1.6-kb DNA fragment containing the gene encoding apolipoprotein A-I from the mouse, Mus musculus, has been cloned and sequenced. It contains three exons separated by two introns and encodes a secreted polypeptide of 262 amino acids (aa), 238 of which constitute the mature protein. Comparisons with the rat and human proteins indicate moderate levels of shared identity (71 and 66%, respectively), although the overall aa compositions yield proteins with identical pIs (5.4). Kyte-Doolittle analyses of the three proteins indicate that there is no significant difference in the structure of these apolipoproteins.


Assuntos
Apolipoproteína A-I/genética , Sequência de Aminoácidos , Animais , Apolipoproteína A-I/química , Sequência de Bases , Clonagem Molecular , Éxons/genética , Biblioteca Genômica , Íntrons/genética , Camundongos , Dados de Sequência Molecular
18.
Gene ; 36(1-2): 169-71, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-2998931

RESUMO

Restriction endonuclease cleavage site maps have been constructed of plasmids pTX14-1, pTX14-2, and pTX14-3 from Bacillus thuringiensis var. israelensis (Bti).


Assuntos
Bacillus thuringiensis/genética , Enzimas de Restrição do DNA/metabolismo , Plasmídeos , Sequência de Bases , Mutação
19.
Int J Radiat Oncol Biol Phys ; 50(1): 107-11, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11316552

RESUMO

PURPOSE: To investigate the incidence of and variables associated with clinically evident fat necrosis in women treated on a protocol of high-dose-rate (HDR) brachytherapy alone without external-beam whole-breast irradiation for early-stage breast carcinoma. METHODS AND MATERIALS: From 6/1997 until 8/1999, 30 women diagnosed with Stage I or II breast carcinoma underwent surgical excision and postoperative irradiation via HDR brachytherapy implant as part of a multi-institutional clinical Phase I/II protocol. Patients eligible included those with T1, T2, N0, N1 (< or = 3 nodes positive), M0 tumors of nonlobular histology with negative surgical margins, no extracapsular lymph-node extension, and a negative postexcision mammogram. Brachytherapy catheters were placed at the initial excision, re-excision, or at the time of axillary sampling. Direct visualization, surgical clips, ultrasound, or CT scans assisted in delineating the target volume defined as the excision cavity plus 2-cm margin. High activity (192)Ir (3-10 Ci) was used to deliver 340 cGy per fraction, 2 fractions per day, for 5 consecutive days to a total dose of 34 Gy to the target volume. Source position and dwell times were calculated using standard volume optimization techniques. Dosimetric analyses were performed with three-dimensional postimplant dose and volume reconstructions. The median follow-up of all patients was 24 months (range, 12-36 months). RESULTS: Eight patients (crude incidence of 27%) developed clinically evident fat necrosis postimplant in the treated breast. Fat necrosis was determined by clinical presentation including pain and swelling in the treated volume, computed tomography, and/or biopsy. All symptomatic patients (7 of 8 cases) were successfully treated with 3 to 12 months of conservative management. Continuous variables that were found to be associated significantly with fat necrosis included the number of source dwell positions (p = 0.04), and the volume of tissue which received fractional doses of 340 cGy, 510 cGy, and 680 cGy (p = 0.03, p = 0.01, and p = 0.01, respectively). Other continuous variables including patient age, total excised tissue volume, tumor size, number of catheters, number of days the catheters were in place, planar separation, dose homogeneity index (DHI), and uniformity index (UI) were not significant. Discrete variables including the presence/absence of DCIS, sentinel versus full axillary nodal assessment, receptor status, presence/absence of diabetes, and the use of chemotherapy or hormone therapy were not found to have a significant association with the risk of fat necrosis. CONCLUSIONS: In this study of HDR brachytherapy of the breast tumor excision cavity plus margin, treatment was planned and delivered in accordance with the dosimetric parameters of the protocol resulting in a high degree of target volume dose homogeneity. Nonetheless, at a median follow-up of 24 months, a high rate of clinically definable fat necrosis occurred. The overall implant volume as reflected in the number of source dwell positions and the volume of breast tissue receiving fractional doses of 340, 510, and 680 cGy were significantly associated with fat necrosis. Future dosimetric optimization algorithms for HDR breast brachytherapy will need to include these factors to minimize the risk of fat necrosis.


Assuntos
Braquiterapia/efeitos adversos , Neoplasias da Mama/radioterapia , Necrose Gordurosa/etiologia , Lesões por Radiação/etiologia , Adulto , Idoso , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Terapia Combinada , Relação Dose-Resposta à Radiação , Feminino , Humanos , Mastectomia Segmentar , Pessoa de Meia-Idade , Estadiamento de Neoplasias
20.
Int J Radiat Oncol Biol Phys ; 45(4): 885-91, 1999 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-10571194

RESUMO

PURPOSE: Young age and extensive intraductal component (EIC) histology have been shown to be associated with increased local recurrence in women treated with breast conservation therapy. This study was conducted to determine if the status of the lumpectomy specimen margin consistently predicted for residual tumor burden risk irrespective of these variables. METHODS AND MATERIALS: As part of an institutional prospective approach for breast conservation therapy (BCT), 265 cases with AJCC Stage I/II carcinoma with an initial excision margin that was < or =2 mm or indeterminate were subjected to reexcision. The probability of residual tumor (+RE) was evaluated with respect to tumor size, histopathologic subtype (invasive ductal carcinoma, invasive ductal carcinoma with an EIC, and invasive lobular carcinoma), relative closeness of the measured margin, and the extent of margin positivity graded as focal, minimal, moderate, or extensive. The amount of residual tumor was graded as microscopic, small, medium, or large. All variables were analyzed for patient age < or =45 or >45 years. RESULTS: There was no significant difference in the incidence of a +RE according to age < or =45 versus >45 years when the margin was >0 < or =2 mm. Of the patients aged < or =45 years, the incidence of a +RE with a margin that was positive as compared to >0 < or =2 mm was 71% vs. 23%, respectively (p = 0.002). For women >45 years old, the difference in the incidence of +RE comparing margins that were positive or >0 < or =2 mm was not significant at 50% vs. 40%, respectively (p = 0.23). For all cases in aggregate, age < or =45 years was associated with a greater incidence of +RE as compared to patients aged >45 years with the discrepant incidence of a +RE by age strata most pronounced for focally positive margins (60% vs. 18%;p< or =0.05). In a logistic regression analysis, age (per year, as a continuous variable) and an EIC histology were significantly associated with the probability of a +RE (odds ratio [OR] = 0.80, p = 0.05 and OR = 1.9, p = 0.01, respectively). Tumor size was not significant (p = 0.23). In patients with an EIC histology, margin status is generally less predictive for differences in the incidence of a +RE. Further, the overall magnitude of difference in the incidence of a +RE related to age appears to be minimized when an EIC histology is present. In contrast, for cases classified as having non-EIC histology, there is a near-linear relationship for both age strata with respect to margin status and the incidence of a +RE. When histology is classified as non-EIC, age < or =45 years is consistently associated with a greater risk of residual tumor for all margin status categories. When the extent of margin positivity was graded as focal or minimal, residual tumor was semiquantitatively estimated as a medium/large amount in 33% versus 26% of cases aged < or =45 or >45 years, respectively (p = 0.62). CONCLUSION: For positive lumpectomy specimen margins, younger age is associated with an increased residual tumor risk. An EIC histology appears to be associated with an elevated risk of residual tumor irrespective of age and may undermine the predictive utility of margin status. Therefore, age and an EIC histology should be factored into risk assessments for residual tumor that rely upon margin assessment.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Lobular/patologia , Carcinoma Lobular/cirurgia , Mastectomia Segmentar , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasia Residual , Probabilidade , Análise de Regressão , Reoperação , Medição de Risco
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