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1.
Sci Rep ; 7(1): 14969, 2017 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-29097670

RESUMO

Approximately 300,000 men around the globe self-identify as Ashkenazi Levites, of whom two thirds were previously shown to descend from a single male. The paucity of whole Y-chromosome sequences precluded conclusive identification of this ancestor's age, geographic origin and migration patterns. Here, we report the variation of 486 Y-chromosomes within the Ashkenazi and non-Ashkenazi Levite R1a clade, other Ashkenazi Jewish paternal lineages, as well as non-Levite Jewish and non-Jewish R1a samples. Cumulatively, the emerging profile is of a Middle Eastern ancestor, self-affiliating as Levite, and carrying the highly resolved R1a-Y2619 lineage, which was likely a minor haplogroup among the Hebrews. A star-like phylogeny, coalescing similarly to other Ashkenazi paternal lineages, ~1,743 ybp, suggests it to be one of the Ashkenazi paternal founders; to have expanded as part of the overall Ashkenazi demographic expansion, without special relation to the Levite affiliation; and to have subsequently spread to non-Ashkenazi Levites.


Assuntos
Cromossomos Humanos Y/genética , Evolução Molecular , Judeus/genética , Frequência do Gene , Variação Genética , Haplótipos , Humanos , Masculino , Filogenia
2.
Cancer Res ; 55(9): 1956-62, 1995 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-7537176

RESUMO

Magnetic resonance imaging has been used to follow noninvasively tumor neovascularization and tumor growth in a model system of multicellular C6 rat glioma spheroids implanted s.c. in nude mice. By positioning a single spheroid approximately 1 cm from the site of incision both the vascularization of the tumor and the wound healing processes were spatially separated and could be simultaneously followed. The model proposed here provides defined initial conditions of tumor geometry and cell proliferative status and separation of initial tumor growth from neovascularization. Magnetic susceptibility relaxation provided an intrinsic marker for blood containing vessels. The implanted spheroid induced vessel growth within 4 days after implantation that was geometrically oriented toward the spheroid and distinct from wound healing at the site of incision. Volume measurements showed a corresponding 4-day lag in growth followed by Gompertz progression. Sham implantation of agarose beads of similar diameter showed no induction of vessel growth, ruling out a direct effect of wound healing. The new vessels penetrating the tumor were highly permeable to the contrast reagent gadolinium-diethylenetriaminepentaacetic acid. This permeability may be due to the action of vascular endothelial growth factor, a major angiogenic growth factor in this system, and a potent permeability factor.


Assuntos
Glioma/irrigação sanguínea , Glioma/patologia , Neovascularização Patológica/fisiopatologia , Animais , Permeabilidade Capilar , Ciclo Celular/fisiologia , Divisão Celular/fisiologia , Imageamento por Ressonância Magnética , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neovascularização Patológica/diagnóstico , Neovascularização Patológica/patologia , Ratos , Células Tumorais Cultivadas
3.
Cancer Res ; 55(1): 153-8, 1995 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-7805026

RESUMO

Cyclocreatine, an analogue of creatine, inhibits tumor cell proliferation in vitro and in vivo. The effects of cyclocreatine in large C6 glioma multicellular spheroids were mapped here by magnetic resonance microscopy. Diffusion-weighted images of C6 glioma spheroids resolved the bright viable rim and the dark necrotic center. Sequential sets of diffusion images, following cyclocreatine administration, showed increasing self-diffusion coefficients of the intracellular water in the viable rim (0.49 x 10(-5) cm2/s for untreated spheroids, 0.62 x 10(-5) cm2/s after 48 h perfusion with 20 mM cyclocreatine). This fact correlated with cellular swelling apparent in histological sections. The radial distribution of cyclocreatine and soluble lipids across perfused C6 spheroids was measured by one-dimensional chemical shift imaging. Cyclocreatine accumulation was prominent throughout the viable cell layer, with no cyclocreatine accumulation in the necrotic center. In both cyclocreatine-treated and control spheroids the lipid signal was highest in the necrotic center and lower in the inner viable cell layer.


Assuntos
Antineoplásicos/farmacologia , Creatinina/análogos & derivados , Glioma/patologia , Animais , Tamanho Celular/efeitos dos fármacos , Células Cultivadas , Creatinina/farmacologia , Espectroscopia de Ressonância Magnética , Ratos , Água/metabolismo
4.
Ann Thorac Surg ; 51(2): 248-52, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1989541

RESUMO

Conduction disturbances after coronary artery bypass grafting may result from compromised septal blood flow. To examine this hypothesis we reviewed the preoperative coronary angiography of 55 consecutive patients undergoing coronary artery bypass grafting. Thirty-five patients had either no lesion or a discrete lesion in the left anterior descending coronary artery that did not include the septal perforator (type I anatomy). Twenty patients had a lesion of the left anterior descending coronary artery at the origin of the first septal branch, a lesion of the first septal artery, or a pair of lesions in the left anterior descending coronary artery that straddled the origin of the first septal artery; all lesions were proximal to the graft site (type II anatomy). None of the patients with type I anatomy had a major conduction disturbance after coronary artery bypass grafting. Eleven of the patients with type II anatomy had major conduction disturbances after coronary artery bypass grafting; right bundle-branch block in 1, right bundle-branch block and left anterior hemiblock in 2, left bundle-branch block in 5, and complete atrioventricular block that required pacemaker implantation in 3 (p less than 0.001). In the 20 patients with type II anatomy, the appearance of conduction disturbances correlated well with the absence of retrograde flow to the septal branches from the right coronary artery (p less than 0.01). Pathological lesions in the left anterior descending coronary artery that compromise flow in the first perforator and that do not provide an adequate circulation produce localized damage and conduction disturbances after coronary artery bypass grafting. This can be predicted from the preoperative angiographic anatomy.


Assuntos
Arritmias Cardíacas/etiologia , Ponte de Artéria Coronária/efeitos adversos , Doença das Coronárias/patologia , Bloqueio Cardíaco/etiologia , Idoso , Angiografia Coronária , Circulação Coronária/fisiologia , Doença das Coronárias/cirurgia , Feminino , Bloqueio Cardíaco/patologia , Bloqueio Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações
5.
J Surg Oncol ; 97(5): 416-22, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18286523

RESUMO

BACKGROUND: This study was conducted to determine survival according to the expression of molecular markers in colorectal cancer (CRC) patients of various ethnic origins. METHODS: Resection of primary tumor was conducted on 171 patients with CRC. Corresponding archived paraffin-embedded blocks were retrieved and tissue microarray (TMA) constructed. Immunohistochemical staining of the TMA for p53, p27 and Ki-67 was quantified by two independent pathologists. Survival was analyzed using the Kaplan-Meier product limit method. RESULTS: With a median follow-up of 65 months, 56 patients (32.7%) died of disease. AJCC stage correlated with disease-free (DFS, P < 0.0001) and overall survival (OS, P < 0.0001). IHC staining was positive for Ki-67 in 77.4%, p53 in 55.8% and p27 in 54.2% of patients. Primary tumor marker expression did not correlate with DFS or OS. The 5-year DFS for Ashkenazi Jews was 75%, significantly higher than Sephardic Jews (SJ) 64% and Palestinian Arabs (PA) 38%, P = 0.001. CONCLUSIONS: Ethnicity among Ashkenazi and SJ and PA appears to have a significant impact on disease outcome in patients with CRC patients, while primary tumor expression of p53, p27 and Ki-67 was unrelated to disease outcome.


Assuntos
Árabes , Neoplasias Colorretais/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Judeus , Antígeno Ki-67/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Fatores Etários , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia , Análise Serial de Proteínas
6.
Magn Reson Med ; 34(2): 213-8, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7476080

RESUMO

The preovulatory rat follicle reaches a diameter of 1 mm with no internal blood vessels. Nutrient supply to the enclosed oocyte depends solely on passive diffusion across the follicular wall and the follicular fluid. Spin-echo and stimulated-echo NMR microscopy experiments were applied here for studying modulations in water diffusion during gonadotropin-induced maturation of perfused rat ovarian follicles (32 degrees C). Two diffusion compartments were observed for the follicular wall. The intracellular water diffusion coefficient, measured at a short diffusion time (9 ms) was 0.28 x 10(-5) cm2/s. Diffusion at long diffusion times was restricted to 16 microns, the size of cells in the follicular wall, and did not change during maturation. In the follicular fluid a transient 26% decrease in the diffusion coefficient was observed 4-7 h after gonadotropin stimulation, a change that is bound to affect the metabolic balance of the oocyte before ovulation.


Assuntos
Água Corporal/efeitos dos fármacos , Gonadotropina Coriônica/farmacologia , Espectroscopia de Ressonância Magnética , Folículo Ovariano/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Animais , Água Corporal/metabolismo , Técnicas de Cultura , Difusão , Espaço Extracelular/efeitos dos fármacos , Espaço Extracelular/metabolismo , Feminino , Líquido Folicular/efeitos dos fármacos , Líquido Folicular/metabolismo , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Aumento da Imagem , Líquido Intracelular/efeitos dos fármacos , Líquido Intracelular/metabolismo , Microscopia , Folículo Ovariano/metabolismo , Folículo Ovariano/fisiologia , Ratos , Ratos Wistar , Células Tecais/efeitos dos fármacos , Células Tecais/metabolismo , Fatores de Tempo
7.
Br J Cancer ; 77(3): 440-7, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9472641

RESUMO

We show here, using high-resolution magnetic resonance imaging, that injured tissue provides a favourable milieu for the neovascularization and growth of C6 glioma spheroids, implanted subcutaneously in nude mice. Moreover, the presence of micro-tumours in an injured tissue inhibited the healing process, leaving an open persistent wound. In correlation with the induced angiogenesis of implanted spheroids in the presence of proximal wounds, a shorter lag period was observed for initiation of tumour growth. This effect was restricted spatially and was observed only for wounds within 5 mm from the tumour. In such proximal wounds, angiogenesis was enhanced in the first days after injury, and vessel regression, which normally starts 4 days after injury, did not occur. Injury causing interference to tumour perfusion promoted tumour vascularization and growth even for more remote incisions, possibly by activating stress-induced angiogenesis. The kinetics of vascularization and growth of these wound-tumour systems sheds light on the clinical observations of increased probability of metastatic recurrence and stimulated regrowth of residual tumour in the site of surgical intervention. High-resolution magnetic resonance imaging could detect the aberrant angiogenic activity of these tumour-wound systems as early as 1 week after injury.


Assuntos
Glioma/irrigação sanguínea , Neovascularização Patológica/etiologia , Ferimentos e Lesões/fisiopatologia , Animais , Imageamento por Ressonância Magnética , Masculino , Camundongos , Ratos , Células Tumorais Cultivadas , Cicatrização
8.
Am J Physiol ; 270(1 Pt 1): C160-9, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8772441

RESUMO

Cyclocreatine (CY), an analogue of creatine, inhibits tumor growth in vivo and proliferation of tumor cells in vitro. The goal of this study was to probe the mechanism of CY transport and cytotoxicity in C6 rat glioma cells and OC238 human ovarian carcinoma cells (creatine kinase activities of 0.16 and 0.016 units/mg protein, respectively). In both cell lines, CY significantly inhibited cell growth with no effect on membrane integrity and on the content of nucleoside triphosphates. An intrinsic 31P-nuclear magnetic resonance (31P-NMR) signal of phosphocreatine, as well as accumulation of phosphocyclocreatine (PCY) after addition of CY, was observed for C6 glioma but not for the OC238 cells. Transport of CY in C6 glioma showed Michaelis-Menten kinetics for an active sodium-dependent component. Transport was reduced more than fivefold in low-glucose medium. The toxicity of CY to C6 glioma cells may be due to PCY accumulation and cellular swelling. Another mechanism must be invoked to explain CY effects on the human ovarian cancer cells in which no PCY accumulation could be detected and no cellular swelling was observed.


Assuntos
Carcinoma/metabolismo , Creatinina/análogos & derivados , Citotoxinas/farmacologia , Glioma/metabolismo , Neoplasias Ovarianas/metabolismo , Animais , Carcinoma/patologia , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular , Creatina Quinase/metabolismo , Creatinina/farmacocinética , Creatinina/farmacologia , Feminino , Glioma/patologia , Glucose/metabolismo , Humanos , Espectroscopia de Ressonância Magnética , Neoplasias Ovarianas/patologia , Fósforo , Ratos , Sódio/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos
9.
Br J Cancer ; 79(9-10): 1392-8, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10188881

RESUMO

The goal of this work was to determine the molecular basis for the induction of tumour vascularization and progression by injury. Magnetic resonance imaging (MRI) studies demonstrated that administration of wound fluid derived from cutaneous injuries in pigs reduced the lag for vascularization and initiation of growth of C6 glioma spheroids, implanted in nude mice, and accelerated tumour doubling time. The former effect can be attributed to the angiogenic capacity of wound fluid as detected in vivo by MRI, and in vitro in promoting endothelial cell proliferation. The latter effect, namely the induced rate of tumour growth, is consistent with the angiogenic activity of wound fluid as well as with the finding that wound fluid was directly mitogenic to the tumour cells, and accelerated growth of C6 glioma in spheroid culture. Of the multiple growth factors present in wound fluid, two key factors, heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF) and platelet-derived growth factor (PDGF), were identified as the dominant mitogens for C6 glioma, and inhibition of their activity using specific neutralizing antibodies suppressed the mitogenic effect of wound fluid on DNA synthesis in C6 glioma. This study suggests that the stimulatory effect of injury on tumour progression can possibly be attenuated by therapeutic targeting directed against a limited number of specific growth factors.


Assuntos
Indutores da Angiogênese/fisiologia , Fator de Crescimento Epidérmico/fisiologia , Neovascularização Patológica/etiologia , Fator de Crescimento Derivado de Plaquetas/fisiologia , Esferoides Celulares/patologia , Ferimentos e Lesões/metabolismo , Indutores da Angiogênese/administração & dosagem , Indutores da Angiogênese/antagonistas & inibidores , Indutores da Angiogênese/metabolismo , Animais , Becaplermina , Divisão Celular , DNA de Neoplasias/biossíntese , Fator de Crescimento Epidérmico/administração & dosagem , Fator de Crescimento Epidérmico/antagonistas & inibidores , Fator de Crescimento Epidérmico/metabolismo , Feminino , Fator 2 de Crescimento de Fibroblastos/administração & dosagem , Fator 2 de Crescimento de Fibroblastos/antagonistas & inibidores , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fator 2 de Crescimento de Fibroblastos/fisiologia , Glioma/irrigação sanguínea , Glioma/patologia , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Imageamento por Ressonância Magnética , Camundongos , Camundongos Nus , Fator de Crescimento Derivado de Plaquetas/administração & dosagem , Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas Proto-Oncogênicas c-sis , Ratos , Suínos
10.
Proc Natl Acad Sci U S A ; 85(20): 7582-6, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2845413

RESUMO

Cellular and viral oncogenes are usually defined on the basis of their ability to elicit neoplastic transformation. However, oncogene activity has also been implicated in the control of differentiation. We have tested whether transfection of primary cultured granulosa cells with various oncogenes can yield cell lines that maintain their differentiated properties. Primary granulosa cells were prepared from diethylstilbestrol-treated immature female rats and transfected with simian virus 40 (SV40) DNA or with SV40 plus activated human Ha-RAS oncogene. Transfection with SV40 plus Ha-RAS yielded cell lines that lost response to gonadotropins but, after 48 hr of stimulation with isoproterenol, cholera toxin, forskolin, or 8-bromoadenosine 3',5'-cyclic monophosphate (8-Br-cAMP), produced progesterone at levels comparable to those of differentiated primary cells. In contrast, cells transformed only by SV40 lost their ability to produce progesterone. Whereas in primary cell cultures progesterone production was already evident after a 3-hr incubation with 1 mM 8-Br-cAMP, in cotransfected cells progesterone production became evident only after 12 hr. All cotransformed cell lines produced SV40 large tumor antigen as well as human RAS p21 protein. The expression of the expected oncogenes in the various cell lines was confirmed by mRNA analysis. These results suggest that the expression of an activated RAS oncogene in granulosa cells can play a role in preserving inducible steroidogenesis.


Assuntos
Genes ras , Células da Granulosa/metabolismo , Progesterona/biossíntese , Vírus 40 dos Símios/fisiologia , Transfecção , Animais , Diferenciação Celular , Linhagem Celular Transformada , Transformação Celular Viral , Células Cultivadas , AMP Cíclico/biossíntese , Feminino , Células da Granulosa/citologia , Células da Granulosa/ultraestrutura , RNA Mensageiro/análise , Ratos
11.
Proc Natl Acad Sci U S A ; 94(24): 13203-8, 1997 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-9371824

RESUMO

We show here that elevated levels of gonadotropins (luteinizing hormone and follicle stimulating hormone), as found in menopause or after ovariectomy, promote growth of human ovarian carcinoma by induction of tumor angiogenesis. Human epithelial ovarian cancer tumors progressed faster in ovariectomized mice. This induced growth could be attributed to the elevated levels of gonadotropins associated with loss of ovarian function because direct administration of gonadotropins also was effective in promoting tumor progression in vivo. On the other hand, gonadotropins had no direct effect on the proliferation of human ovarian cancer cells in vitro. Using MRI, we demonstrated that ovariectomy significantly (P < 0.02) induces neovascularization of human ovarian carcinoma spheroids implanted in nude mice. Moreover, conditioned medium of gonadotropin-treated human ovarian carcinoma cells showed increased mitogenic activity to bovine endothelial cells, and this activity could be blocked by neutralizing antibodies against luteinizing hormone and against vascular endothelial growth factor. Accordingly, gonadotropin stimulation resulted in a dose-dependent-induced expression of vascular endothelial growth factor in monolayer culture as well as in the outer proliferating cells of human ovarian cancer spheroids. These results demonstrate the significance of the elevated levels of gonadotropins, as found in menopause and in all ovarian cancer patients, on the progression of ovarian cancer and could explain the protective effect of estrogen replacement therapy. Based on these results, we suggest that hormonal therapy aimed at lowering the circulating levels of gonadotropins may possibly prolong remission in ovarian cancer by extending tumor dormancy.


Assuntos
Neovascularização Patológica/fisiopatologia , Neoplasias Ovarianas/irrigação sanguínea , Ovário/fisiopatologia , Animais , Fatores de Crescimento Endotelial/genética , Feminino , Hormônio Foliculoestimulante/metabolismo , Humanos , Hibridização In Situ , Hormônio Luteinizante/metabolismo , Linfocinas/genética , Imageamento por Ressonância Magnética , Menopausa , Camundongos , Camundongos Nus , Neoplasias Ovarianas/fisiopatologia , Ovariectomia , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
12.
Am J Perinatol ; 10(3): 194-6, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8517894

RESUMO

Congenital dislocation of the knee was diagnosed antenatally in an abdominal flat plate. This is probably the first time that this condition has been diagnosed prior to delivery. Examination of the newborn after delivery revealed dislocation of the right hip and knee. The obstetric and orthopedic implications and suggested treatment are discussed.


Assuntos
Doenças Fetais/diagnóstico por imagem , Luxação Congênita de Quadril/diagnóstico por imagem , Luxações Articulares/congênito , Articulação do Joelho , Diagnóstico Pré-Natal , Adolescente , Apresentação Pélvica , Feminino , Luxação Congênita de Quadril/terapia , Humanos , Recém-Nascido , Luxações Articulares/diagnóstico por imagem , Luxações Articulares/terapia , Gravidez , Radiografia
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