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1.
Gynecol Oncol ; 150(1): 56-60, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29859673

RESUMO

OBJECTIVE: The Silva invasion pattern-based classification system stratifies endocervical adenocarcinomas (ECAs) into 3 categories corresponding to risk of metastasis and recurrence, but has only been evaluated for HPV-associated ECAs of usual type. We examined whether the Silva system is applicable to all endocervical adenocarcinomas, especially those not associated with HPV. METHODS: Complete slide sets from 341 surgical specimens of ECA were collected from 7 institutions worldwide. All specimens were associated with clinical records covering at least 5 years of follow-up. Tumors were classified as HPV-associated (HPVA) or not (NHPVA) by both morphology and detection of HPV using in situ hybridization. Recurrence and survival were analyzed by multivariate Mantel-Haenszel methods. RESULTS: Most specimens (292; 85.6%) were HPVA, while 49 (14.3%) were NHPVA. All NHPVAs were Silva pattern C, while 76.0% of HPVAs were pattern C, 14.7% pattern A, and 9.3% pattern B. Including both HPVAs and NHPVAs, lymphovascular invasion (LVI) was detected in 0% of pattern A, 18.5% of pattern B and 62.6% of pattern C cases (p < 0.001). None of the pattern A or B cases were associated with lymph node metastases (LNM), in contrast to pattern C cases (21.8%). Among patients with Silva pattern C ECA, those with HPVA tumors had a lower recurrence rate and better survival than those with NHPVA; however, when adjusted for stage at diagnosis, the difference in recurrence and mortality was small and not statistically significant. CONCLUSIONS: Application of the Silva system is only relevant in HPVA cervical adenocarcinoma.


Assuntos
Adenocarcinoma/patologia , Metástase Linfática/imunologia , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/patologia , Neoplasias do Colo do Útero/patologia , Adenocarcinoma/mortalidade , Feminino , Humanos , Recidiva Local de Neoplasia , Fatores de Risco , Taxa de Sobrevida , Neoplasias do Colo do Útero/mortalidade
2.
Br J Cancer ; 112(5): 925-33, 2015 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-25688738

RESUMO

BACKGROUND: Nulliparity is an endometrial cancer risk factor, but whether or not this association is due to infertility is unclear. Although there are many underlying infertility causes, few studies have assessed risk relations by specific causes. METHODS: We conducted a pooled analysis of 8153 cases and 11 713 controls from 2 cohort and 12 case-control studies. All studies provided self-reported infertility and its causes, except for one study that relied on data from national registries. Logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Nulliparous women had an elevated endometrial cancer risk compared with parous women, even after adjusting for infertility (OR=1.76; 95% CI: 1.59-1.94). Women who reported infertility had an increased risk compared with those without infertility concerns, even after adjusting for nulliparity (OR=1.22; 95% CI: 1.13-1.33). Among women who reported infertility, none of the individual infertility causes were substantially related to endometrial cancer. CONCLUSIONS: Based on mainly self-reported infertility data that used study-specific definitions of infertility, nulliparity and infertility appeared to independently contribute to endometrial cancer risk. Understanding residual endometrial cancer risk related to infertility, its causes and its treatments may benefit from large studies involving detailed data on various infertility parameters.


Assuntos
Neoplasias do Endométrio/epidemiologia , Neoplasias do Endométrio/etiologia , Infertilidade Feminina/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Paridade , Fatores de Risco , Autorrelato
3.
Nat Rev Cancer ; 5(12): 977-85, 2005 12.
Artigo em Inglês | MEDLINE | ID: mdl-16341085

RESUMO

Most cases of breast and prostate cancer are not associated with mutations in known high-penetrance genes, indicating the involvement of multiple low-penetrance risk alleles. Studies that have attempted to identify these genes have met with limited success. The National Cancer Institute Breast and Prostate Cancer Cohort Consortium--a pooled analysis of multiple large cohort studies with a total of more than 5,000 cases of breast cancer and 8,000 cases of prostate cancer--was therefore initiated. The goal of this consortium is to characterize variations in approximately 50 genes that mediate two pathways that are associated with these cancers--the steroid-hormone metabolism pathway and the insulin-like growth factor signalling pathway--and to associate these variations with cancer risk.


Assuntos
Neoplasias da Mama/genética , Genes Neoplásicos , Penetrância , Neoplasias da Próstata/genética , Neoplasias da Mama/metabolismo , Estudos de Coortes , Feminino , Hormônios Esteroides Gonadais/metabolismo , Humanos , Masculino , Neoplasias da Próstata/metabolismo
4.
Ann Oncol ; 24 Suppl 8: viii37-viii41, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24131968

RESUMO

Mammographic density (MD), representing connective and epithelial tissue (fibroglandular tissue, FGT) is a major risk factor for breast cancer. In an analysis of an autopsy series (Bartow SA, Pathak DR, Mettler FA. Radiographic microcalcification and parenchymal patterns as indicators of histologic "high-risk" benign breast disease. Cancer 1990; 66: 1721-1725, Bartow SA, Pathak DR, Mettler FA et al. Breast mammographic pattern: a concatenation of confounding and breast cancer risk factors. Am J Epidemiol 1995; 142: 813-819), MD was found to be strongly correlated with the collagen and epithelial content of the breast (Li T, Sun L, Miller N et al. The association of measured breast tissue characteristics with MD and other risk factors for breast cancer. Cancer Epidemiol Biomarkers Prev 2005; 14: 343-349), and another report showed that breast epithelium was highly concentrated in the areas of collagen concentration (Hawes D, Downey S, Pearce CL et al. Dense breast stromal tissue shows greatly increased concentration of breast epithelium but no increase in its proliferative activity. Breast Cancer Res 2006; 8: R24). Collagen comprises the overwhelming majority of the FGT, occupying an area on the slides obtained from the autopsy series some 15 times the area of glandular tissue. The relationship of MD with breast cancer risk appears likely to be due to a major extent to increasing epithelial cell numbers with increasing MD. FGT is also seen in breast magnetic resonance imaging (breast MRI) and, as expected, it has been shown that this measure of FGT (MRI-FGT) is highly correlated with MD. A contrast-enhanced breast MRI shows that normal FGT 'enhances' (background parenchymal enhancement, BPE) after contrast agent is administered(Morris EA. Diagnostic breast MR imaging: current status and future directions. Radiol Clin North Am 2007; 45: 863-880, vii., Kuhl C. The current status of breast MR imaging. Part I. Choice of technique, image interpretation, diagnostic accuracy, and transfer to clinical practice. Radiology 2007; 244: 356-378), and a recent study suggests that BPE is also a major breast cancer risk factor, possibly as important as, and independent of MD (King V, Brooks JD, Bernstein JL et al. BPE at breast MR imaging and breast cancer risk. Radiology 2011; 260: 50-60). BPE is much more sensitive to the effects of menopause and tamoxifen than is FGT (King V, Gu Y, Kaplan JB et al. Impact of menopausal status on BPE and fibroglandular tissue on breast MRI. Eur Radiol 2012; 22: 2641-2647, King V, Kaplan J, Pike MC et al. Impact of tamoxifen on amount of fibroglandular tissue, BPE, and cysts on breast MRI. Breast J 2012; 18: 527-534). Changes in MD and BPE may be most useful in predicting response to chemopreventive agents aimed at blocking breast cell proliferation. More study of the biological basis of the effects of MD and BPE is needed if we are to fully exploit these factors in developing chemopreventive approaches to breast cancer.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Imageamento por Ressonância Magnética , Glândulas Mamárias Humanas/anormalidades , Mama/patologia , Densidade da Mama , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Mamografia , Fatores de Risco
5.
Sports Biomech ; : 1-12, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33660587

RESUMO

Our purpose was to compare the mechanical properties of the protective outer shells of various athletic helmets in their final, fully manufactured form. Sections were taken from 3 different helmet shells (Bauer RE-AKT hockey helmet, Cascade R lacrosse helmet, and Riddell Speedflex football helmet) at 4 different locations (front, side, top, and rear) for a total of 12 test specimens. The 4 specimens from each helmet shell were potted together in epoxy resin moulds and mechanically polished. The hardness, elastic modulus and phase angle were measured using dynamic nanoindentation performed at 100 Hz with an oscillation amplitude of 1 nm (rms). Repeated ANOVA analysis was used to compare each of the dependent variables for each of the 3 helmets across the 4 different locations. The interaction between helmet type and location was significant for hardness (F6,63 = 2.84, P = 0.032, Pη2 = 0.21), elastic modulus (F6,63 = 6.412, P < 0.001, Pη2 = 0.38), and phase angle (F6,63 = 7.65, P < 0.001, Pη2 = 0.42). Polycarbonate has a higher ability to dissipate mechanical energy making it the recommended superior choice for helmet shells. In addition, the results lead us to speculate that manufacturing causes changes in the molecular weight or the distribution of fillers across locations for polyethylene but not for polycarbonate since mechanical properties are fairly uniform over the surface of football helmets, at least within a given helmet.

6.
J Exp Med ; 152(1): 31-40, 1980 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-7400755

RESUMO

A human monocyte-like cell line, U937, when grown in continuous culture, does not secrete lysosomal enzymes or migrate towards chemotactic factors. When the cells are stimulated by lymphokines, however, they develop the ability both to migrate directionally and to secrete enzymes in response to several types of chemoattractants. The development, by stimulated cells, of chemotactic and secretory responses to one class of chemoattractants, the N- formylated peptides, is accompanied by the appearance on the cells of specific binding sites for these substances. Using tritiated N-formyl- methionyl-leueyl-phenylalanine (fMet-Leu-[(3)H]Phe) as a ligand, it was determined that unstimulated U937 cells possess no detectable binding sites. However, after stimulation with lymphocyte culture supernates for 24, 48, and 72 h, they developed 4,505 (+/-) 1,138, 22,150(+/-) 4,030, and 37,200 (+/-) 8,000 sites/cell, respectively. The dissociation constants for the interaction of fMet-Leu-[SH]Phe with the binding sites were approximately the same regardless of stimulation time and ranged between 15 and 30 nM. The binding of fMet-Leu-[(3)H]Phe by stimulated U937 cells was rapid and readily reversed by the addition of a large excess of unlabeled peptide. The affinity of a series of N-formylated peptides for binding to U937 cells exactly reflected the potency of the peptides in inducing lysosomal enzyme secretion and chemotaxis. The availability of a continuous human monocytic cell line that can be induced to express receptors for N-formylated peptides will provide a useful tool not only for the characterization of such receptors but also for the delineation of regulatory mechanisms involved in cellular differentiation and the chemotactic response.


Assuntos
Fatores Quimiotáticos/metabolismo , Linfocinas/farmacologia , Metionina/análogos & derivados , Monócitos/fisiologia , N-Formilmetionina/análogos & derivados , Oligopeptídeos/metabolismo , Receptores de Droga/metabolismo , Sítios de Ligação , Ligação Competitiva , Linhagem Celular , Quimiotaxia de Leucócito , Glucuronidase/metabolismo , Humanos , Cinética , Lisossomos/enzimologia , Monócitos/citologia , Monócitos/metabolismo , Muramidase/metabolismo , N-Formilmetionina/metabolismo , N-Formilmetionina Leucil-Fenilalanina , Fatores de Tempo , Trítio
7.
J Exp Med ; 148(1): 93-102, 1978 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-353219

RESUMO

Several tissue culture lines of 6C3HED, a murine lymphoma, were more susceptible to immunologic destruction in vivo than the highly virulent 6C3HED line maintained by serial intramuscular transplantation. The attenuated tissue culture cells were rejected by normal syngeneic recipients, but thymectomized mice were unable to reject attenuated cells. In such mice, the growth rate of attenuated cells was equivalent to the growth rate of virulent cells in normal syngeneic mice. The increased susceptibility of attenuated cells to destruction by syngeneic hosts was shown to correlate with decreased production by the tumor cells of a macrophage chemotaxis inhibitor, and not with altered antigen density. In addition, when inhibitor isolated from virulent cells was administered to mice challenged with attenuated cells, the latter cells became virulent in vivo. When attenuated and virulent cells were administered simultaneously in the same host, the attenuated cells were able to develop into progressively growing tumors. The data suggest that the successful growth of neoplastic cells in normal may require tumor cells to produce factors which subvert the ability of the host to mobilize macrophages rapidly at the tumor site.


Assuntos
Quimiotaxia , Linfoma/imunologia , Fatores Inibidores da Migração de Macrófagos/imunologia , Macrófagos/imunologia , Animais , Antígenos de Neoplasias , Linhagem Celular , Masculino , Camundongos , Neoplasias Experimentais/imunologia , Timo/imunologia , Virulência
9.
Br J Cancer ; 100(5): 834-9, 2009 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-19174821

RESUMO

We investigated the association between urinary tract infections (UTIs) and transitional cell carcinoma of the bladder in a population-based case-control study in Los Angeles covering 1586 cases and age-, gender-, and race-matched neighbourhood controls. A history of bladder infection was associated with a reduced risk of bladder cancer among women (odds ratio (OR), 0.66; 95% confidence interval (CI), 0.46-0.96). No effect was found in men, perhaps due to power limitations. A greater reduction in bladder cancer risk was observed among women with multiple infections (OR, 0.37; 95% CI, 0.18-0.78). Exclusion of subjects with a history of diabetes, kidney or bladder stones did not change the inverse association. A history of kidney infections was not associated with bladder cancer risk, but there was a weak association between a history of other UTIs and slightly increased risk among men. Our results suggest that a history of bladder infection is associated with a reduced risk of bladder cancer among women. Cytotoxicity from antibiotics commonly used to treat bladder infections is proposed as one possible explanation.


Assuntos
Carcinoma de Células de Transição/epidemiologia , Carcinoma de Células de Transição/etiologia , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/etiologia , Infecções Urinárias/epidemiologia , Adulto , Carcinoma de Células de Transição/patologia , Estudos de Casos e Controles , Regulação para Baixo , Feminino , Humanos , Los Angeles/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Caracteres Sexuais , Fumar/epidemiologia , Neoplasias da Bexiga Urinária/patologia
10.
Br J Cancer ; 100(6): 993-1001, 2009 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-19240718

RESUMO

Low-moderate risk alleles that are relatively common in the population may explain a significant proportion of the excess familial risk of ovarian cancer (OC) not attributed to highly penetrant genes. In this study, we evaluated the risks of OC associated with common germline variants in five oncogenes (BRAF, ERBB2, KRAS, NMI and PIK3CA) known to be involved in OC development. Thirty-four tagging SNPs in these genes were genotyped in approximately 1800 invasive OC cases and 3000 controls from population-based studies in Denmark, the United Kingdom and the United States. We found no evidence of disease association for SNPs in BRAF, KRAS, ERBB2 and PIK3CA when OC was considered as a single disease phenotype; but after stratification by histological subtype, we found borderline evidence of association for SNPs in KRAS and BRAF with mucinous OC and in ERBB2 and PIK3CA with endometrioid OC. For NMI, we identified a SNP (rs11683487) that was associated with a decreased risk of OC (unadjusted P(dominant)=0.004). We then genotyped rs11683487 in another 1097 cases and 1792 controls from an additional three case-control studies from the United States. The combined odds ratio was 0.89 (95% confidence interval (CI): 0.80-0.99) and remained statistically significant (P(dominant)=0.032). We also identified two haplotypes in ERBB2 associated with an increased OC risk (P(global)=0.034) and a haplotype in BRAF that had a protective effect (P(global)=0.005). In conclusion, these data provide borderline evidence of association for common allelic variation in the NMI with risk of epithelial OC.


Assuntos
Predisposição Genética para Doença , Oncogenes , Neoplasias Ovarianas/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Classe I de Fosfatidilinositol 3-Quinases , Feminino , Genes erbB-2 , Genótipo , Haplótipos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras) , Proteínas ras/genética
11.
Magn Reson Med ; 61(3): 615-25, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19235262

RESUMO

The poor prognosis associated with malignant glioma is largely attributable to its invasiveness and robust angiogenesis. Angiogenesis involves host-tumor interaction and requires in vivo evaluation. Despite their versatility, few studies have used mouse glioma models with perfusion MRI approaches, and generally lack longitudinal study design. Using a micro-MRI system (8.5 Tesla), a novel dual bolus-tracking perfusion MRI strategy was implemented. Using the small molecule contrast agent Magnevist, dynamic contrast enhanced MRI was implemented in the intracranial 4C8 mouse glioma model to determine K(trans) and v(e), indices of tumor vascular permeability and cellularity, respectively. Dynamic susceptibility contrast MRI was subsequently implemented to assess both cerebral blood flow and volume, using the macromolecular superparamagnetic iron oxide, Feridex, which circumvented tumor bolus susceptibility curve distortions from first-pass extravasation. The high-resolution parametric maps obtained over 4 weeks, indicated a progression of tumor vascularization, permeability, and decreased cellularity with tumor growth. In conclusion, a comprehensive array of key parameters were reliably quantified in a longitudinal mouse glioma study. The syngeneic 4C8 intracerebral mouse tumor model has excellent characteristics for studies of glioma angiogenesis. This approach provides a useful platform for noninvasive and highly diagnostic longitudinal investigations of anti-angiogenesis strategies in a relevant orthotopic animal model.


Assuntos
Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/fisiopatologia , Compostos Férricos , Glioma/irrigação sanguínea , Glioma/fisiopatologia , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Neovascularização Patológica/patologia , Animais , Velocidade do Fluxo Sanguíneo , Linhagem Celular Tumoral , Meios de Contraste , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Peso Molecular , Permeabilidade
12.
J Cell Biol ; 91(1): 221-6, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7298717

RESUMO

Chemotactic factors have been shown to inhibit the methylation of phosphatidylethanolamine in macrophages without affecting total phospholipid synthesis. It would thus be anticipated that newly synthesized membranes of macrophages exposed to chemoattractants would have an increased ratio of phosphatidylethanolamine to its methylated derivatives. These ratios were measured directly in newly synthesized phospholipids of plasma membranes isolated from guinea pig peritoneal macrophages. The phosphatidylethanolamine: methylated phospholipid ratio in such plasma membranes was increased by 53 to 111% upon exposure of the cells to chemotactic factors. This increase was due to decreased synthesis of methylated phospholipids and not to altered formation of phosphatidylethanolamine or activation of phospholipases. Methylated phospholipid ratios were also studied in the leading front lamellipodia isolated from macrophages migrating under chemotactic and nonchemotactic conditions. The phosphatidylethanolamine:methylated phospholipid ratios were increased up to fourfold in lamellipodia of macrophages migrating towards chemotactic agents when compared to those from cells migrating randomly. Biophysical changes in the plasma membrane produced by an increase in the ratio of phosphatidylethanolamine:methylated phospholipids as a result of exposure of cells to chemoattractants may be required for sustained directed migration.


Assuntos
Quimiotaxia de Leucócito , Macrófagos/fisiologia , Fosfatidiletanolaminas/metabolismo , Animais , Membrana Celular/metabolismo , Fatores Quimiotáticos/farmacologia , Complemento C5/farmacologia , Cobaias , Lipídeos de Membrana/metabolismo , Metilação , N-Formilmetionina/análogos & derivados , N-Formilmetionina/farmacologia , N-Formilmetionina Leucil-Fenilalanina , Oligopeptídeos/farmacologia , Fosfatidilcolinas/metabolismo
13.
J Cell Biol ; 98(2): 444-8, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6319428

RESUMO

The binding characteristics of the oligopeptide chemoattractant receptor on guinea pig macrophages and macrophage membrane preparations were characterized using detailed binding studies and computer analysis. Viable macrophages bound the radiolabeled chemoattractant N-formyl-methionyl-leucyl-[3H]phenylalanine with single dissociation constant (KD) of 18.4 +/- 4.6 nM with 15,300 +/- 1,800 sites per cell. Binding data from membrane preparations indicated the presence of two classes of binding sites with KD of 1.5 +/- 0.4 nM and 25.5 +/- 11.0 nM. Approximately 23% of the receptors were in the high affinity state. In the presence of added guanine nucleotide di- or triphosphates, the high affinity receptors in the membrane preparations were converted to low affinity states with no change in the total receptor number. Nonhydrolyzable derivatives of GTP were most potent in converting the receptor from its high to low affinity state. These data suggest that the affinity state of the oligopeptide chemoattractant receptor in macrophages is regulated by guanine nucleotides and GTPase, implying that the transduction mechanisms of this receptor may be controlled by a guanine nucleotide regulatory unit.


Assuntos
Nucleotídeos de Guanina/farmacologia , Macrófagos/metabolismo , N-Formilmetionina Leucil-Fenilalanina/metabolismo , Oligopeptídeos/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Membrana Celular/metabolismo , Computadores , Cobaias , Cinética , Receptores de Superfície Celular/efeitos dos fármacos , Receptores de Formil Peptídeo , Relação Estrutura-Atividade
14.
Science ; 209(4455): 493-5, 1980 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-6248959

RESUMO

The chemotaxis of leukocytes appears to be initiated by the binding of chemotactic factors to the surface of these cells. N-Formylated peptides induce chemotaxis and lysosomal enzyme secretion of leukocytes; because these peptides are available in a purified radiolabeled form, they have been useful in the characterization of receptors for chemotactic factors. Equine polymorphonuclear leukocytes secrete lysosomal enzymes but do not exhibit chemotaxis in respone to the N-formylated peptides, even though they have a high-affinity cell surface receptor for these agents. The specificity of the equine receptor resembles the specificity of the receptor on chemotactically responsive leukocytes from other species. Equine polymorphonuclear leukocytes may thus be an excellent model for the study of the events that lead to a biological response following receptor occupancy.


Assuntos
Leucócitos/fisiologia , Oligopeptídeos/fisiologia , Receptores de Superfície Celular/fisiologia , Animais , Quimiotaxia , Cavalos , Cinética , Leucócitos/metabolismo , Oligopeptídeos/sangue , Receptores de Formil Peptídeo , Relação Estrutura-Atividade
15.
Science ; 192(4237): 370-2, 1976 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-946556

RESUMO

The accumulation of macrophages at neoplastic sites may be an important event in immunologically mediated tumor killing. The implantation of syngeneic neoplasms in mice, however, was found to depress the animal's ability to localize macrophages at inflammatory sites. A low-molecular-weight (6,000 to 10,000) factor released by growing neoplasms that inhibits the accumulation of macrophages in vivo and chemotactic responsiveness in vitro was identified. The factor is active in the inhibition of macrophages and is ineffectual at retarding the migration of polymorphonuclear leukocytes. Neoplastic cells may thus abrogate immunosurveillance by releasing products that prevent potentially tumoricidal macrophages from accumulating at sites of developing malignancies.


Assuntos
Quimiotaxia , Macrófagos/imunologia , Neoplasias Experimentais/imunologia , Animais , Linhagem Celular , Fibrossarcoma/imunologia , Linfoma não Hodgkin/imunologia , Macrófagos/fisiologia , Camundongos , Camundongos Endogâmicos C3H , Peso Molecular , Neoplasias Experimentais/análise , Neutrófilos/imunologia , Neutrófilos/fisiologia , Solubilidade
16.
Science ; 249(4971): 902-5, 1990 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-2392680

RESUMO

A general measure of the rate of senescence is the acceleration of mortality rate, represented here by the time required for the mortality rate to double (MRD). Rhesus monkeys have an MRD close to that of humans, about 8 years; their shorter life-span results mainly from higher mortality at all ages. In contrast, some groups with short life-spans (rodents and galliform birds) have shorter MRDs and faster senescence. On the basis of the Gompertz mortality rate model, one may estimate the MRD from the maximum life-span (tmax) and the overall population mortality rate. Such calculations show that certain birds have MRDs that are as long as that of humans. These results show that high overall mortality rates or small body sizes do not preclude slow rates of senescence.


Assuntos
Envelhecimento , Grupos de População Animal , Hominidae , Mortalidade , Adolescente , Adulto , Animais , Aves , Humanos , Mamíferos , Matemática , Modelos Estatísticos
17.
Science ; 254(5035): 1131-8, 1991 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-1957166

RESUMO

This is the threshold of an era when many of the most prevalent human cancers can, to a significant extent, be prevented through life-style changes or medical interventions. For lung cancer, the leading cause of cancer deaths in the United States, the major cause, cigarette smoking, is known and strategies for reducing smoking are slowly succeeding. Dietary changes can reduce the risk of developing large bowel cancer, the second most common cancer overall. The etiology of the major cancer in women, cancer of the breast, is sufficiently well understood that large-scale medical intervention trials are imminent. Recent changes in the incidence and mortality of these and the other major human cancers are reviewed with a brief explanation as to why these changes have occurred, followed by a summary of the state of knowledge regarding the major causes of cancer.


Assuntos
Neoplasias/prevenção & controle , Dieta , Hormônios/fisiologia , Humanos , Neoplasias/epidemiologia , Neoplasias/etiologia , Plantas Tóxicas , Estudos Prospectivos , Nicotiana , Estados Unidos
18.
Science ; 259(5095): 633-8, 1993 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-8381558

RESUMO

The use of oral contraceptives in the United States during the past three decades has led to a dramatic decline in the incidence of cancers of the ovary and endometrium. The magnitude of these declines was predictable both from epidemiologic data and from the biologic effects of oral contraceptives on these tissues. Although the incidence of breast cancer has not been substantially affected by current oral contraceptives, it may be possible to develop alternative forms of contraception that provide protection against all three cancers. The major goal of hormonal chemoprevention of cancer is to reduce cell proliferation in the relevant epithelial tissue. New chemopreventive agents such as tamoxifen exemplify the application of this principle.


Assuntos
Anticarcinógenos/uso terapêutico , Neoplasias da Mama/prevenção & controle , Anticoncepcionais Orais/uso terapêutico , Neoplasias do Endométrio/prevenção & controle , Neoplasias Ovarianas/prevenção & controle , Progestinas/uso terapêutico , Tamoxifeno/uso terapêutico , Inibidores de 5-alfa Redutase , Adulto , Fatores Etários , Idoso , Androstenos/uso terapêutico , Azasteroides/uso terapêutico , Neoplasias da Mama/epidemiologia , Neoplasias do Endométrio/epidemiologia , Neoplasias do Endométrio/mortalidade , Terapia de Reposição de Estrogênios , Feminino , Finasterida , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/mortalidade , Neoplasias da Próstata/prevenção & controle , Reino Unido/epidemiologia , Estados Unidos/epidemiologia
19.
Neuropediatrics ; 40(3): 103-11, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20020394

RESUMO

OBJECTIVE: The aim of this study is to describe the long-term neurological, neuropsychological and neuroradiological sequelae and to determine prognostic factors for neurological outcome in children with neuroblastoma-associated opsoclonus-myoclonus-ataxia (OMA) syndrome. METHODS: Data on medical history were collected for the study patients. Examinations with grading of neurological signs, neuropsychological tests and brain magnetic resonance imaging with spectroscopy were performed during a follow-up clinic. RESULTS: Fourteen subjects entered the study. All had localized neuroblastoma and they were evaluated after a median of 7.8 years. Patients with a chronic/multiphasic neurological course received steroids combined with intravenous immunoglobulins in the majority of cases. 71% presented neurological sequelae and 62% had a full-scale IQ below the normal range. All patients showed at least some deficit in the neuropsychological functions assessed (language, visual-motor integration, memory, attention and motor ability). Long-term deficits were more frequently detected in patients with an interval of more than 2 months between OMA onset and its diagnosis, even if in most comparisons statistical significance was not reached. Cerebellar atrophy, observed in 36% of patients, was not associated with the neurological outcome. CONCLUSIONS: Persisting disability is present in most children with neuroblastoma-associated OMA. However, our results support the role of an early diagnosis of OMA in reducing sequelae and encourage the use of new immunosuppressive therapies.


Assuntos
Neoplasias Encefálicas/complicações , Neuroblastoma/complicações , Síndrome de Opsoclonia-Mioclonia/complicações , Neoplasias Encefálicas/diagnóstico por imagem , Criança , Pré-Escolar , Transtornos Cognitivos/etiologia , Progressão da Doença , Feminino , Humanos , Imunoglobulinas/administração & dosagem , Testes de Inteligência , Estudos Longitudinais , Masculino , Neuroblastoma/diagnóstico por imagem , Exame Neurológico , Testes Neuropsicológicos , Síndrome de Opsoclonia-Mioclonia/diagnóstico por imagem , Síndrome de Opsoclonia-Mioclonia/tratamento farmacológico , Cintilografia , Estudos Retrospectivos , Distúrbios da Fala/etiologia , Estatísticas não Paramétricas , Esteroides/uso terapêutico , Adulto Jovem
20.
J Neuroimmunol ; 201-202: 221-6, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18687475

RESUMO

Opsoclonus-myoclonus syndrome or Dancing Eye Syndrome (OMS/DES) is a rare neurological disorder of children, which associates with neuroblastoma (NB) in approximately 50% of cases. We examined sera from five patients with (OMS-NB(+)) and five without NB (OMS-NB(-)) for autoantibodies. OMS-NB(-) IgG bound to the surface of a NB cell line, whereas IgG from OMS-NB(+) and from NB patients without OMS/DES bound only to permeabilised cells. Both OMS-NB(+) and OMS-NB(-) reduced proliferation of NB cells. We also present a case report of a child with OMS/DES without NB who made a complete recovery without treatment. Serum antibodies at presentation bound to the surface and decreased NB cell proliferation but had decreased 9 weeks later when the child was asymptomatic. These results demonstrate that sera from some OMS/DES patients contain IgG antibodies that are potentially pathogenic.


Assuntos
Autoanticorpos/sangue , Proliferação de Células/efeitos dos fármacos , Síndrome de Opsoclonia-Mioclonia/imunologia , Análise de Variância , Animais , Autoanticorpos/farmacologia , Canais de Cálcio/imunologia , Linhagem Celular , Cerebelo/metabolismo , Pré-Escolar , Feminino , Citometria de Fluxo/métodos , Glutamato Descarboxilase/metabolismo , Humanos , Lactente , Masculino , Neuroblastoma/sangue , Neuroblastoma/complicações , Neuroblastoma/imunologia , Síndrome de Opsoclonia-Mioclonia/sangue , Síndrome de Opsoclonia-Mioclonia/complicações , Canais de Potássio/metabolismo , Ligação Proteica/efeitos dos fármacos , Radioimunoensaio/métodos , Ratos , Tetrazóis/metabolismo , Fatores de Tempo
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