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1.
J Pathol Clin Res ; 6(1): 83-93, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31591823

RESUMO

ΔNp63, also known as p40, regulates stemness of normal mammary gland epithelium and provides stem cell characteristics in basal and HER2-driven murine breast cancer models. Whilst ΔNp63/p40 is a characteristic feature of normal basal cells and basal-type triple-negative breast cancer, some receptor-positive breast cancers express ΔNp63/p40 and its overexpression imparts cancer stem cell-like properties in ER+ cell lines. However, the incidence of ER+ and HER2+ tumours that express ΔNp63/p40 is unclear and the phenotype of ΔNp63/p40+ cells in these tumours remains uncertain. Using immunohistochemistry with p63 isoform-specific antibodies, we identified a ΔNp63/p40+ tumour cell subpopulation in 100 of 173 (58%) non-triple negative breast cancers and the presence of this population associated with improved survival in patients with ER- /HER2+ tumours (p = 0.006). Furthermore, 41% of ER+ /PR+ and/or HER2+ locally metastatic breast cancers expressed ΔNp63/p40, and these cells commonly accounted for <1% of the metastatic tumour cell population that localised to the tumour/stroma interface, exhibited an undifferentiated phenotype and were CD44+ /ALDH- . In vitro studies revealed that MCF7 and T47D (ER+ ) and BT-474 (HER2+ ) breast cancer cell lines similarly contained a small subpopulation of ΔNp63/p40+ cells that increased in mammospheres. In vivo, MCF7 xenografts contained ΔNp63/p40+ cells with a similar phenotype to primary ER+ cancers. Consistent with tumour samples, these cells also showed a distinct location at the tumour/stroma interface, suggesting a role for paracrine factors in the induction or maintenance of ΔNp63/p40. Thus, ΔNp63/p40 is commonly present in a small population of tumour cells with a distinct phenotype and location in ER+ and/or HER2+ human breast cancers.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Células-Tronco Neoplásicas/patologia , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Biomarcadores Tumorais/análise , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Feminino , Xenoenxertos , Humanos , Camundongos , Células-Tronco Neoplásicas/metabolismo , Fenótipo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo
2.
J Pathol ; 233(3): 238-46, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24687952

RESUMO

Many human cancers contain missense TP53 mutations that result in p53 protein accumulation. Although generally considered as a single class of mutations that abrogate wild-type function, individual TP53 mutations may have specific properties and prognostic effects. Tumours that contain missense TP53 mutations show variable p53 stabilization patterns, which may reflect the specific mutation and/or aspects of tumour biology. We used immunohistochemistry on cell lines and human breast cancers with known TP53 missense mutations and assessed the effects of each mutation with four structure-function prediction methods. Cell lines with missense TP53 mutations show variable percentages of cells with p53 stabilization under normal growth conditions, ranging from approximately 50% to almost 100%. Stabilization is not related to structural or functional disruption, but agents that stabilize wild-type p53 increase the percentages of cells showing missense mutant p53 accumulation in cell lines with heterogeneous stabilization. The same heterogeneity of p53 stabilization occurs in primary breast cancers, independent of the effect of the mutation on structural properties or functional disruption. Heterogeneous accumulation is more common in steroid receptor-positive or HER2-positive breast cancers and cell lines than in triple-negative samples. Immunohistochemcal staining patterns associate with Mdm2 levels, proliferation, grade and overall survival, whilst the type of mutation reflects downstream target activity. Inhibiting Mdm2 activity increases the extent of p53 stabilization in some, but not all, breast cancer cell lines. The data indicate that missense mutant p53 stabilization is a complex and variable process in human breast cancers that associates with disease characteristics but is unrelated to structural or functional properties. That agents which stabilize wild-type p53 also stabilize mutant p53 has implications for patients with heterogeneous mutant p53 accumulation, where therapy may activate mutant p53 oncogenic function.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama/genética , Mutação de Sentido Incorreto , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Estresse Fisiológico , Proteína Supressora de Tumor p53/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Humanos , Gradação de Tumores , Fenótipo , Conformação Proteica , Estabilidade Proteica , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Relação Estrutura-Atividade , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/metabolismo
3.
Br J Cancer ; 110(8): 2063-71, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24577057

RESUMO

BACKGROUND: Various markers are used to identify the unique sub-population of breast cancer cells with stem cell properties. Whether these markers are expressed in all breast cancers, identify the same population of cells, or equate to therapeutic response is controversial. METHODS: We investigated the expression of multiple cancer stem cell markers in human breast cancer samples and cell lines in vitro and in vivo, comparing across and within samples and relating expression with growth and therapeutic response to doxorubicin, docetaxol and radiotherapy. RESULTS: CD24, CD44, ALDH and SOX2 expression, the ability to form mammospheres and side-population cells are variably present in human cancers and cell lines. Each marker identifies a unique rather than common population of cancer cells. In vivo, cells expressing these markers are not specifically localized to the presumptive stem cell niche at the tumour/stroma interface. Repeated therapy does not consistently enrich cells expressing these markers, although ER-negative cells accumulate. CONCLUSIONS: Commonly employed methods identify different cancer cell sub-populations with no consistent therapeutic implications, rather than a single population of cells. The relationships of breast cancer stem cells to clinical parameters will require identification of specific markers or panels for the individual cancer.


Assuntos
Neoplasias da Mama/genética , Resistencia a Medicamentos Antineoplásicos/genética , Células-Tronco Neoplásicas/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Antígeno CD24/biossíntese , Antígeno CD24/imunologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Receptores de Hialuronatos/biossíntese , Receptores de Hialuronatos/imunologia , Células MCF-7 , Fatores de Transcrição SOXB1/biossíntese , Fatores de Transcrição SOXB1/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Fam Cancer ; 13(2): 249-55, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24509884

RESUMO

Our study aimed to assess the diagnostic utility of magnetic resonance enterography (MRE) compared to capsule endoscopy (CE) for the detection of small bowel polyps in patients with Peutz-Jeghers syndrome (PJS); with findings verified by balloon enteroscopy (BE). Adult patients were prospectively recruited across two tertiary centres and underwent MRE followed by CE, with a subsequent BE performed in patients with significant (≥10 mm) polyps. The primary endpoint was the total number of significant (≥10 mm) small bowel polyps detected. The number of patients with at least one significant polyp, correlation with BE findings, and patients' preferences were secondary endpoints. A total of 20 patients (7 male; mean age 34.9 years) underwent both investigations. The number of polyps ≥10 mm detected by CE was greater than by MRE (47 vs 14 polyps, P = 0.02). The number of patients with at least one significant polyp identified by CE was 11 (55 %) compared with 7 (35 %) identified by MRE (P = 0.25). Subsequent BE in 12 patients identified a total of 26 significant polyps in 8 patients. The positive predictive value of finding a polyp at BE was higher for MRE (100 %) compared to CE (60 %). Overall patient preferences identified CE as the preferred modality. This prospective study demonstrated that CE identifies significantly more small bowel polyps compared with MRE in patients with PJS. Correlation between the two techniques and subsequent BE however was relatively poor.


Assuntos
Endoscopia por Cápsula , Pólipos Intestinais/diagnóstico , Imageamento por Ressonância Magnética , Síndrome de Peutz-Jeghers/complicações , Vigilância da População/métodos , Adulto , Meios de Contraste , Enteroscopia de Duplo Balão , Feminino , Humanos , Pólipos Intestinais/etiologia , Masculino , Preferência do Paciente , Valor Preditivo dos Testes , Estudos Prospectivos
5.
Cancer Chemother Pharmacol ; 71(2): 473-80, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23178956

RESUMO

PURPOSE: Trastuzumab, effective in about 15 % of women with breast cancer, downregulates signalling through the Akt/PI3K and MAPK pathways. These pathways modulate glucose and phospholipid metabolism which can be monitored by [(18)F]FDG-PET and (31)P-NMR spectroscopy, respectively. Here, the relationship between response of HER-2 overexpressing tumours and changes in [(18)F]-FDG incorporation and (31)P-NMR-detectable phosphomonoesters were examined. EXPERIMENTAL: Xenografts derived from HER2-overexpressing MDA-MB-453 human breast tumour cells were grown in SCID mice, treated with trastuzumab for 15 days, then [(18)F]-FDG uptake determined and (31)P-NMR carried out on chemical extracts of the tumours. Western blots were carried out to determine protein expression of Hexokinase II and glut1. RESULTS: [(18)F]-FDG incorporation, Hexokinase II and glut1 protein expression and the concentration of phosphocholine and phosphoethanolamine in chemical extracts subjected to (31)P-NMR were significantly decreased in the xenografts in the trastuzumab-treated mice compared with xenografts from the PBS-injected group. CONCLUSIONS: Changes in FDG incorporation and (31)P-NMR spectral changes can accompany response of HER2-expressing breast cancer xenografts to trastuzumab. This is the first study to show parallel changes in [(18)F]FDG- and (31)P-NMR-detectable metabolites accompany response to targeted anticancer treatment.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Fluordesoxiglucose F18/metabolismo , Transportador de Glucose Tipo 1/análise , Hexoquinase/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Neoplasias Mamárias Experimentais/tratamento farmacológico , Receptor ErbB-2/análise , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , Camundongos SCID , Trastuzumab , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Br J Cancer ; 106(6): 1117-22, 2012 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-22361631

RESUMO

BACKGROUND: Observations that diabetics treated with biguanide drugs have a reduced risk of developing cancer have prompted an enthusiasm for these agents as anti-cancer therapies. We sought to determine the efficacy of the biguanide phenformin in the chemoprophylaxis and in the treatment of oestrogen receptor (ER)-positive MCF7 and receptor triple-negative MDAMB231 xenografts in immunocompromised mice. We also compared the efficacy of phenformin and metformin in the treatment of MDAMB231. METHODS: Immunocompromised mice were divided into groups: (1) phenformin administered for 2 weeks prior to cell injection; (2) established tumours treated with phenformin; (3) established tumours treated with metformin (only for MDAMB231 tumours); (4) untreated controls. Post-treatment tumours, liver and spleen were harvested for further analysis. RESULTS: Phenformin significantly inhibited both the development and growth of MCF7 and MDAMB231 tumours, and for MDAMB231 at greater efficacy than metformin without murine toxicity. The number of mitotic figures was significantly fewer in xenografts treated with phenformin compared with controls. Results suggested that the mechanism of action of phenformin in vivo is consistent with AMPK activation. CONCLUSION: Phenformin has clinical potential as an antineoplastic agent and should be considered for clinical trials both in ER-positive and triple-negative breast cancer.


Assuntos
Anticarcinógenos/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias da Mama/prevenção & controle , Metformina/uso terapêutico , Fenformin/uso terapêutico , Adenilato Quinase/metabolismo , Animais , Anticarcinógenos/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Ativação Enzimática , Feminino , Histonas/metabolismo , Humanos , Antígeno Ki-67/metabolismo , Fígado/enzimologia , Metformina/farmacologia , Camundongos , Camundongos Nus , Fenformin/farmacologia , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/metabolismo , Baço/enzimologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Cancer Res ; 70(23): 9808-15, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21084272

RESUMO

Radiotherapy is a key treatment option for breast cancer, yet the molecular responses of normal human breast epithelial cells to ionizing radiation are unclear. A murine subcutaneous xenograft model was developed in which nonneoplastic human breast tissue was maintained with the preservation of normal tissue architecture, allowing us to study for the first time the radiation response of normal human breast tissue in situ. Ionizing radiation induced dose-dependent p53 stabilization and p53 phosphorylation, together with the induction of p21(CDKN1A) and apoptosis of normal breast epithelium. Although p53 was stabilized in both luminal and basal cells, induction of Ser392-phosphorylated p53 and p21 was higher in basal cells and varied along the length of the ductal system. Basal breast epithelial cells expressed ΔNp63, which was unchanged on irradiation. Although stromal responses themselves were minimal, the response of normal breast epithelium to ionizing radiation differed according to the stromal setting. We also demonstrated a dose-dependent induction of γ-H2AX foci in epithelial cells that was similarly dependent on the stromal environment and differed between basal and luminal epithelial cells. The intrinsic differences between human mammary cell types in response to in vivo irradiation are consistent with clinical observation that therapeutic ionizing radiation is associated with the development of basal-type breast carcinomas. Furthermore, there may be clinically important stromal-epithelial interactions that influence DNA damage responses in the normal breast. These findings demonstrate highly complex responses of normal human breast epithelium following ionizing radiation exposure and emphasize the importance of studying whole-tissue effects rather than single-cell systems.


Assuntos
Mama/efeitos da radiação , Epitélio/efeitos da radiação , Modelos Animais , Animais , Apoptose/efeitos da radiação , Mama/metabolismo , Caspase 3/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Relação Dose-Resposta à Radiação , Ativação Enzimática/efeitos da radiação , Células Epiteliais/metabolismo , Células Epiteliais/efeitos da radiação , Epitélio/metabolismo , Feminino , Histonas/metabolismo , Humanos , Imuno-Histoquímica , Camundongos , Camundongos SCID , Fosforilação/efeitos da radiação , Serina/metabolismo , Fatores de Tempo , Transplante Heterólogo , Proteína Supressora de Tumor p53/metabolismo
8.
J Intern Med ; 268(3): 252-64, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20337854

RESUMO

OBJECTIVE: We hypothesized that there is an association between haemochromatosis genotype C282Y/C282Y and/or iron overload and risk of hypertension and/or left ventricular hypertrophy (LVH). METHODS: We analysed data from a cross-sectional study of the general population including 8992 individuals from the Copenhagen City Heart Study (CCHS), a follow-up study of 36,480 individuals from the Copenhagen General Population Study (CGPS), and a case-only study of 3815 Scandinavians from the Losartan Intervention For End-point Reduction in Hypertension Genetic Substudy (LIFEGEN) with LVH and hypertension. RESULTS: In the CCHS, individuals with C282Y/C282Y versus wild type/wild type had an odds ratio for antihypertensive medication use of 4.8 (1.8-13; P = 0.003). In the CGPS, the corresponding hazard ratio was 1.7 (1.0-2.3; P = 0.003). Also, hazard ratios for antihypertensive medication use in the CGPS were 1.6 (1.0-2.6; P = 0.05) for transferrin saturation > or =80% vs. <50%, and 2.3 (1.3-4.2; P = 0.005) for C282Y/C282Y + transferrin saturation > or =80% vs. wild type/wild type + transferrin saturation <50%. These results were most pronounced in men above 55 years of age. We did not find any association between C282Y/C282Y or iron overload and LVH or hypertension (measured as blood pressure at a single occasion or continuous blood pressure), or LVH with hypertension in the CCHS or with severity of LVH in LIFEGEN. CONCLUSIONS: We found that haemochromatosis genotype C282Y/C282Y and extremely elevated transferrin saturation either separately or combined were associated with increased risk of antihypertensive medication use. Therefore, testing for haemochromatosis genotype C282Y/C282Y and extreme transferrin saturation could be considered in patients with essential hypertension.


Assuntos
Hemocromatose/complicações , Hipertensão/etiologia , Hipertrofia Ventricular Esquerda/etiologia , Sobrecarga de Ferro/complicações , Fatores Etários , Idoso , Anti-Hipertensivos/administração & dosagem , Estudos Transversais , Esquema de Medicação , Uso de Medicamentos/estatística & dados numéricos , Feminino , Seguimentos , Genótipo , Hemocromatose/sangue , Hemocromatose/genética , Humanos , Hipertensão/genética , Hipertrofia Ventricular Esquerda/genética , Sobrecarga de Ferro/genética , Masculino , Pessoa de Meia-Idade , Transferrina/análise
9.
Int J Radiat Biol ; 85(11): 1026-31, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19895279

RESUMO

PURPOSE: With the increasing use of radiation as adjuvant therapy in breast cancer, the effects of gamma radiation on the remaining normal breast are of increasing importance. The complexities of multiple cellular types within breast tissues and the role of the pleiotropic Tumour Protein 53 (TP53, p53) protein with its downstream transcriptional targets and cellular processes may be central to the effects on residual normal breast tissues. CONCLUSION: While a detailed understanding of p53 protein-mediated responses in normal breast tissues remains elusive, p53 appears to have a pivotal role in the effects of gamma radiation on normal breast epithelium, but not stromal cells, which may account for the differing clinical effects of gamma radiation in women treated for breast cancer.


Assuntos
Mama/metabolismo , Mama/efeitos da radiação , Raios gama/efeitos adversos , Proteína Supressora de Tumor p53/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/radioterapia , Feminino , Expressão Gênica/efeitos da radiação , Genes p53/efeitos da radiação , Humanos , Modelos Biológicos , Radioterapia Adjuvante , Transdução de Sinais/efeitos da radiação , Proteína Supressora de Tumor p53/genética
10.
Acta Physiol (Oxf) ; 197 Suppl 673: 1-68, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19744082

RESUMO

AIM: Muscle strength is an excellent indicator of general health when based on reliable measurements. Muscle strength data for a healthy population are rare or non-existent. The aim of the present study was to measure a set of normal values for isometric and isokinetic muscle strength for all the major joint movements of the body and, from these data, to create a basis for comparison of the muscle strength of an individual with the expected value in a normal population. METHODS: A randomly selected group, aged 20-80 years, from the Copenhagen City Heart Study were studied. The group was subgrouped according to age and gender. Isometric and isokinetic muscle strength was measured in each subject across the main joints in the body. A statistical model was developed that encompassed the three main muscle groups: upper limbs, trunk and lower limbs. RESULTS: Muscle strength in healthy men decreases in a linear fashion from the age of 25 years down to between 54% and 89% at the age of 75 years, and seems not highly dependent on any other parameter than age. For women, the muscle strength is dependent on weight and is only related to age from around 40 years of age. The decrease in muscle strength from the age around 40 to 75 years is 48-92%. For most muscle groups, men are 1.5-2 times stronger than women, with the oldest men having strength similar to that observed among the youngest women. CONCLUSION: We developed a model to compare the isometric and isokinetic muscle strength of all the major joint movements of an individual with values for a healthy man or woman at any age in the range of 20-80 years. In all age groups, women have lower muscle strength than men. Men's muscle strength declines with age, while women's muscle strength declines from the age of 41 years.


Assuntos
Contração Isométrica/fisiologia , Força Muscular/fisiologia , Adulto , Fatores Etários , Idoso , Fenômenos Biomecânicos , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Aptidão Física , Padrões de Referência , Fatores Sexuais , Adulto Jovem
11.
Neurology ; 68(13): 1025-31, 2007 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-17389307

RESUMO

OBJECTIVE: We tested the hypothesis that the HFE genotypes H63D/H63D, H63D/wild type, C282Y/H63D, C282Y/C282Y, and C282Y/wild type are risk factors for symptomatic carotid atherosclerosis, ischemic cerebrovascular disease (ICVD), and ischemic stroke. METHODS: We performed an age- and gender-matched case-control study of 701 cases with symptomatic carotid atherosclerosis vs 2,777 controls, and a prospective study of 9,178 individuals from the Danish general population followed for 24 years, during which 504 developed ICVD, of whom 393 had ischemic stroke. RESULTS: Genotype was not consistently associated with symptomatic carotid atherosclerosis. The cumulative incidences of ICVD and ischemic stroke by age were increased for H63D/H63D vs wild type/wild type (log-rank: p = 0.003 and p < 0.001). H63D/H63D vs wild type/wild type had an age- and multifactorially adjusted hazard ratio of 2.0 (95% CI: 1.2 to 3.2; p = 0.007) and 2.1 (1.3 to 3.5; p = 0.004) for ICVD and of 2.4 (1.4 to 4.0; p = 0.001) and 2.8 (1.7 to 4.6; p < 0.001) for ischemic stroke; these remained significant after correction for multiple comparisons. Other hereditary hemochromatosis genotypes were not associated with ICVD or ischemic stroke. CONCLUSIONS: Hereditary hemochromatosis H63D homozygosity predicts a two- to threefold risk of ICVD and ischemic stroke.


Assuntos
Isquemia Encefálica/epidemiologia , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Hemocromatose/epidemiologia , Hemocromatose/genética , Acidente Vascular Cerebral/epidemiologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Doenças das Artérias Carótidas/epidemiologia , Estudos de Casos e Controles , Comorbidade , Análise Mutacional de DNA , Dinamarca/epidemiologia , Feminino , Testes Genéticos , Genótipo , Hemocromatose/fisiopatologia , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco
12.
Calcif Tissue Int ; 79(1): 1-6, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16868669

RESUMO

Using digital X-ray radiogrammetry (DXR) on hand radiographs from a large population-based study, 1,370 postmenopausal women were evaluated in a prospective fashion; fracture occurrence was compared with DXR measurements of historic radiographs. Further, the aim of the study was to evaluate factors affecting DXR bone mineral density (BMD) in this cohort. The study is based on data from a subgroup of women participating in the third Copenhagen City Heart Study and additional data from a questionnaire obtained in 1999. The mean follow-up time was 6.1 years. During the observation period, 245 women suffered a fracture. Odds ratios (ORs) per 1 standard deviation decline in DXR-BMD were statistically significant for fracture in the groups of wrist fractures, proximal humerus fractures, vertebral fractures, and other fractures as well as in the total fracture group. In the hip fracture group, the P value almost reached significance (0.052). The highest ORs (2.4) were found in the group with proximal humerus fractures and in the vertebral fracture group (2.0). In the wrist fracture and hip fracture groups, ORs were 1.7 and 1.4, respectively. The group with other fractures had an OR of 1.7, and the OR in the entire fracture group was 1.6. Age, fracture, and smoking were negatively correlated with DXR-BMD, whereas BMI, age at menopause, hormone replacement therapy, and physical fitness and muscle strength were positively correlated with DXR-BMD. In conclusion, BMD estimated by DXR of the metacarpals predicts later osteoporotic fracture and seems to provide meaningful information on bone mass in epidemiological studies, where DXA measurements are not available.


Assuntos
Absorciometria de Fóton/métodos , Fraturas Ósseas/diagnóstico por imagem , Osteoporose Pós-Menopausa/diagnóstico por imagem , Idoso , Densidade Óssea , Estudos de Casos e Controles , Estudos de Coortes , Intervalos de Confiança , Feminino , Fraturas Ósseas/epidemiologia , Mãos/diagnóstico por imagem , Fraturas do Quadril/diagnóstico por imagem , Fraturas do Quadril/epidemiologia , Humanos , Úmero/diagnóstico por imagem , Úmero/lesões , Estudos Longitudinais , Pessoa de Meia-Idade , Razão de Chances , Osteoporose Pós-Menopausa/epidemiologia , Estudos Prospectivos , Fatores de Risco , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/epidemiologia , População Urbana , Traumatismos do Punho/epidemiologia , Traumatismos do Punho/fisiopatologia
13.
Endoscopy ; 38(6): 613-6, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16612744

RESUMO

BACKGROUND AND STUDY AIMS: The role of acetic acid spray during magnification chromocolonoscopy has not previously been evaluated. We aimed to compare the accuracy of predicting polyp histology at magnification colonoscopy, using acetic acid and indigo carmine, either alone or in combination. PATIENTS AND METHODS: A total of 46 consecutive patients with polyps detected during colonoscopy which measured 10 mm or less were alternately divided into two groups. In group A patients, 1.5 % acetic acid was applied to the mucosa first, followed by indigo carmine spray; in group B patients, the order was reversed. The pit pattern was assessed after application, in real time. All the lesions were resected and examined histologically. RESULTS: Altogether, 37 adenomas and 36 hyperplastic polyps were evaluated. In group A, the diagnostic accuracy after spraying with acetic acid was 95 %, which increased to 98 % after application of indigo carmine. In group B, the accuracy after indigo carmine application was 83 %. After subsequent spraying with acetic acid, images were enhanced in 70 % of patients, with an increase in accuracy to 97 %. The mean time required to obtain an initial clear image with the first dye was 14 seconds for both groups. CONCLUSIONS: This is the first description of the use of acetic acid for pit pattern analysis of colonic polyps. Its ease of use, low cost, and safety, together with its excellent accuracy in the assessment of polyp pit patterns suggest that this method could easily be applied to routine magnification colonoscopy.


Assuntos
Ácido Acético , Pólipos do Colo/diagnóstico , Colonoscopia/métodos , Indicadores e Reagentes/administração & dosagem , Ácido Acético/administração & dosagem , Administração Tópica , Diagnóstico Diferencial , Feminino , Humanos , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
14.
Intern Med J ; 35(4): 234-9, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15836502

RESUMO

Capsule endoscopy represents a significant advance in the investigation of small bowel diseases and the beginning of wireless endoscopic imaging. Capsule endoscopy involves swallowing a video capsule endoscope, which is painless and relatively safe. Its use has been established for suspected small bowel bleeding, and the role of capsule endoscopy in the investigation of inflammatory bowel disease, iatrogenic disease, polyposis syndromes and coeliac disease is evolving. It is likely that in many instances it will become the next test after standard endoscopic evaluation. Early data suggest that capsule endoscopy improves outcome in patients with suspected small bowel bleeding, but more data are required on outcomes for the other indications.


Assuntos
Endoscopia Gastrointestinal/métodos , Endoscópios , Endoscopia Gastrointestinal/tendências , Gastroenteropatias/diagnóstico , Humanos
15.
Cancer Res ; 64(14): 4875-86, 2004 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15256458

RESUMO

The acquisition of resistance to apoptosis, the cell's intrinsic suicide program, is essential for cancers to arise and progress and is a major reason behind treatment failures. We show in this article that small molecule antagonists of the sigma-1 receptor inhibit tumor cell survival to reveal caspase-dependent apoptosis. sigma antagonist-mediated caspase activation and cell death are substantially attenuated by the prototypic sigma-1 agonists (+)-SKF10,047 and (+)-pentazocine. Although several normal cell types such as fibroblasts, epithelial cells, and even sigma receptor-rich neurons are resistant to the apoptotic effects of sigma antagonists, cells that can promote autocrine survival such as lens epithelial and microvascular endothelial cells are as susceptible as tumor cells. Cellular susceptibility appears to correlate with differences in sigma receptor coupling rather than levels of expression. In susceptible cells only, sigma antagonists evoke a rapid rise in cytosolic calcium that is inhibited by sigma-1 agonists. In at least some tumor cells, sigma antagonists cause calcium-dependent activation of phospholipase C and concomitant calcium-independent inhibition of phosphatidylinositol 3'-kinase pathway signaling. Systemic administration of sigma antagonists significantly inhibits the growth of evolving and established hormone-sensitive and hormone-insensitive mammary carcinoma xenografts, orthotopic prostate tumors, and p53-null lung carcinoma xenografts in immunocompromised mice in the absence of side effects. Release of a sigma receptor-mediated brake on apoptosis may offer a new approach to cancer treatment.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Receptores sigma/antagonistas & inibidores , Animais , Apoptose/fisiologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Sinalização do Cálcio/efeitos dos fármacos , Carbazóis/farmacologia , Caspases/metabolismo , Bovinos , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Linhagem Celular Tumoral , Ativação Enzimática , Etilenodiaminas/farmacologia , Haloperidol/farmacologia , Humanos , Isoenzimas/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Nus , Fosfolipase C delta , Piperazinas/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt , Fosfolipases Tipo C/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Receptor Sigma-1
16.
Br J Cancer ; 88(8): 1281-4, 2003 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-12698197

RESUMO

In the treatment of breast cancer, combination chemotherapy is used to overcome drug resistance. Combining doxorubicin and vinorelbine in the treatment of patients with metastatic breast cancer has shown high response rates; even single-agent vinorelbine in patients previously exposed to anthracyclines results in significant remission. Alterations in protein kinase-mediated signal transduction and p53 mutations may play a role in drug resistance with cross-talk between signal transduction and p53 pathways. The aim of this study was to establish the effects of doxorubicin and vinorelbine, as single agents, in combination, and as sequential treatments, on signal transduction and p53 in the breast cancer cell lines MCF-7 and MDA-MB-468. In both cell lines, increased p38 activity was demonstrated following vinorelbine but not doxorubicin treatment, whether vinorelbine was given prior to or simultaneously with doxorubicin. Mitogen-activated protein kinase (MAPK) activity and p53 expression remained unchanged following vinorelbine treatment. Doxorubicin treatment resulted in increased p53 expression, without changes in MAPK or p38 activity. These findings suggest that the effect of doxorubicin and vinorelbine used in combination may be achieved at least in part through distinct mechanisms. This additivism, where doxorubicin acts via p53 expression and vinorelbine through p38 activation, may contribute to the high clinical response rate when the two drugs are used together in the treatment of breast cancer.


Assuntos
Doxorrubicina/farmacologia , Genes p53/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Vimblastina/análogos & derivados , Vimblastina/farmacologia , Neoplasias da Mama , Linhagem Celular Tumoral , Interações Medicamentosas , Feminino , Humanos , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Proteína Supressora de Tumor p53/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Vinorelbina , Proteínas Quinases p38 Ativadas por Mitógeno
17.
Eur Heart J ; 23(4): 315-24, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11812068

RESUMO

AIMS: To evaluate the prevalence and the independent prognosis of electrocardiographic left ventricular hypertrophy by voltage only, ST depression and negative T wave, isolated negative T wave and left ventricular hypertrophy plus ST depression and negative T wave for cardiac morbidity and mortality, without known ischaemic heart disease at baseline. METHODS AND RESULTS: Follow-up data from the Copenhagen City Heart Study were used. Subjects were 5243 men and 6391 women, age range 25-74 years. End-points were (1) myocardial infarction, (2) ischaemic heart disease and (3) cardiovascular disease mortality. Relative risk was age- and sex-adjusted, and multivariately adjusted for known cardiovascular risk factors. During 7 years follow-up, left ventricular hypertrophy plus ST depression and negative T wave had an age-adjusted relative risk of 3.78 (95% confidence interval 2.29-6.25) for myocardial infarction, 4.27 (2.95-6.16) for ischaemic heart disease and 3.75 (2.41-5.85) for cardiovascular disease. A negative T wave, ST depression and negative T wave changes, and left ventricular hypertrophy with negative T wave also carry independent prognostic information for myocardial infarction, ischaemic heart disease and cardiovascular disease. CONCLUSIONS: Electrocardiographic left ventricular hypertrophy with ST depression and negative T wave changes are the electrocardiographic abnormalities with the greatest prognostic information for future cardiac events. Electrocardiographic negative T waves, ST depression and negative T wave abnormalities and left ventricular hypertrophy with negative T waves, also have prognostic information.


Assuntos
Eletrocardiografia , Hipertrofia Ventricular Esquerda/epidemiologia , Adulto , Idoso , Doenças Cardiovasculares/mortalidade , Dinamarca/epidemiologia , Feminino , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Isquemia Miocárdica/mortalidade , Prevalência , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Risco
18.
Lancet ; 358(9291): 1405-9, 2001 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-11705485

RESUMO

BACKGROUND: Although genotyping studies suggest that hereditary haemochromatosis is one of the most common genetic disorders in white people, it is still thought of as an uncommon disease. Our aim was to test the hypothesis that hereditary haemochromatosis is a disease often overlooked in patients with late-onset type 1 diabetes mellitus, a late manifestation of untreated iron overload. METHODS: We did a retrospective study in which we genotyped for the C282Y and H63D mutations in the haemochromatosis gene in 716 unselected Danish patients who developed type 1 diabetes mellitus after age 30 years and 9174 controls from the general Danish population. We also screened for hereditary haemochromatosis by assessment of transferrin saturation. FINDINGS: More patients with diabetes (n=9, relative frequency 1.26%, 95% CI 0.58-2.37) than controls (23, 0.25%, 0.16-0.38) were homozygous for C282Y (odds ratio 4.6, 2.0-10.1, p=0.0001). These patients had unrecognised signs of haemochromatosis. Transferrin saturation and ferritin concentrations ranged from 57% to 102% and 17 microg/L to 8125 microg/L, respectively. Frequency of compound heterozygosity (C282Y/H63D) did not differ between patients with diabetes (eight) and controls (131) (odds ratio 0.8, 95% CI 0.4-1.7). Positive and negative predictive values of transferrin saturation greater than 50%, in identification of C282Y homozygosity, were 0.26 and 1.00, respectively. A saturation of less than 50% therefore excluded C282Y homozygosity, whereas a saturation of more than 50% suggested C282Y homozygosity. INTERPRETATION: Measurement of transferrin saturation followed by genetic testing could prevent liver and heart problems and improve life expectancy in patients with diabetes. Population screening before the onset of diabetes might improve the outlook of patients even further, but will be less cost effective.


Assuntos
Diabetes Mellitus Tipo 1/genética , Hemocromatose/genética , Transferrina/metabolismo , Adulto , Análise de Variância , Dinamarca/epidemiologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/epidemiologia , Feminino , Genótipo , Hemocromatose/complicações , Hemocromatose/epidemiologia , Humanos , Hepatopatias/enzimologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos
19.
APMIS ; 109(7-8): 517-24, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11552949

RESUMO

Veterans who have participated in the Gulf War suffer from a number of symptoms, collectively referred to as the Gulf War Syndrome. It has been hypothesized that a change in the systemic cytokine balance or other changes in immunological parameters could be responsible for some of the symptoms. We analyzed the peripheral blood natural killer (NK) cell activity of 686 Gulf War personnel who had been present in the Persian Gulf area during and immediately after the Gulf War as well as 231 gender and age-matched controls. The test material included individual samples of frozen peripheral blood mononuclear cells kept at -139 degrees C for a period of 50 to 380 days prior to NK cell analysis of freshly thawed cells. Significant differences in NK-cell activity were not observed by direct comparison of the levels of natural cytotoxic activity in the two groups. However, NK-cell cytotoxicity as such decreased due to cryopreservation. Surprisingly, the NK cells obtained from control donors were significantly (p<0.0001) more sensitive to freezing conditions than cells from the Gulf War personnel, leaving the marginal comparison between the two groups untrustworthy, in particular because of the marked difference between the -139 degrees C storage times used for the two groups. Freshly thawed samples of peripheral blood T lymphocytes (CD2+ cells) from 109 randomly selected Gulf War personnel and 68 gender- and age-matched controls were stimulated for 3 days with phytohemagglutinin followed by 4 h activation by phorbol ester and ionomycin, and were stained for intracellular content of interleukin-2, -5, -10 and interferon-gamma. As with natural cytotoxicity, the length of cell storage at -139 degrees C influenced the production of cytokines. No significant differences in the cytokine production between the two groups were observed when the influence of the storage period was taken into consideration. Together, these data suggest that no overall long-term effects on NK-cell function and T-cell cytokine production are present in the Danish Gulf War personnel. Moreover, cryopreservation is a major potential source of bias when studying the physiology of thawed NK and T cells.


Assuntos
Células Matadoras Naturais/imunologia , Síndrome do Golfo Pérsico/imunologia , Adulto , Estudos Transversais , Citocinas/biossíntese , Citotoxicidade Imunológica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Gastrointest Endosc ; 54(1): 79-83, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11427849

RESUMO

BACKGROUND: Methods are needed for propulsion of endoscopes and wireless video capsules along the small intestine. This work aims to test the hypothesis that electrical stimulation could propel an endoscope by stimulating muscular contraction. METHODS: Prototype acrylic ovoid-shaped devices were constructed with 2 stainless steel electrodes mounted on the tapered section. Five devices 15 to 23 mm diameter with a taper of 28 degrees to 40 degrees (included angle) were tested. When these devices were in contact with the bowel wall, electrostimulation was applied causing circular muscle contraction, which when applied to the taper of the ovoid resulted in forward propulsion of the device. The method does not induce peristalsis but works by stimulating local contraction. The device was tested in the small intestine and esophagus of anesthetized pigs. RESULTS: Electrostimulation caused the ovoid to advance rapidly (6 mm/sec) up and down the esophagus by inducing circular esophageal muscle contraction. When stimulated at 15 Hz with 30-ms pulses, the threshold for movement in the small intestine was 12 mA; at 20 mA the device moved reliably in either direction in the small intestine at speeds of up to 4.5 mm/sec and negotiated tight curves. CONCLUSION: Electrostimulation can move endoscopes in the small intestine.


Assuntos
Estimulação Elétrica/instrumentação , Endoscópios Gastrointestinais , Motilidade Gastrointestinal/fisiologia , Animais , Eletrodos , Desenho de Equipamento , Estudos de Viabilidade , Contração Isométrica/fisiologia , Músculo Liso/fisiologia , Peristaltismo/fisiologia , Suínos
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