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1.
Artigo em Inglês | MEDLINE | ID: mdl-19240369

RESUMO

BACKGROUND: The role of bone morphogenetic proteins (BMPs) in bone healing has been demonstrated in numerous in vivo animal models. BMP-2, -4 and -7 have also been shown to stimulate the differentiation of human and animal stem cells into osteoblasts in vitro. There are, however, contradictory reports of BMPs causing apoptosis and inhibition of proliferation of osteoblastic cells. Therefore, a more complete understanding of the effects of BMP-2, -4 and -7 on human osteoblasts is required. METHODS: Cells of the immortalised human fetal osteoblastic line hFOB 1.19 were exposed to recombinant human (rh) BMP-2, -4 and -7. In addition, primary human osteoblasts were exposed to rhBMP-7. Cell proliferation was measured using a colorimetric assay. Apoptotic cells were detected using the TUNEL assay. RESULTS: The hFOB cells exposed in a dose-dependent manner to rhBMP-2, -4 and -7 had significantly lower rates of proliferation than non-treated cells, (p<0.01 for rhBMP-2, -4 and -7). The proliferation results for rhBMP-7 were replicated using primary human osteoblasts. Additionally, rhBMP-2, -4 and -7 induced a significantly higher rate of apoptosis in the hFOB cells, with a temporal and dose-dependent pattern (p<0.05), irrespective of the presence of serum growth factors. CONCLUSIONS: Despite interest in the potential clinical application of BMPs to improve bone healing, further studies are necessary to determine their full biological function before they can be used confidently in humans.


Assuntos
Apoptose/efeitos dos fármacos , Proteína Morfogenética Óssea 2/farmacologia , Proteína Morfogenética Óssea 4/farmacologia , Proteína Morfogenética Óssea 7/farmacologia , Proliferação de Células/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Proteína Morfogenética Óssea 2/administração & dosagem , Proteína Morfogenética Óssea 4/administração & dosagem , Proteína Morfogenética Óssea 7/administração & dosagem , Linhagem Celular Transformada , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Marcação In Situ das Extremidades Cortadas , Osteoblastos/citologia , Osteoblastos/fisiologia , Proteínas Recombinantes/farmacologia , Fatores de Tempo
2.
J Alzheimers Dis ; 7(4): 325-30, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16131735

RESUMO

Neurodegeneration is associated with increased frequency of neurological soft signs (NSS). We designed the present study to investigate the association between NSS and subjective memory complaints, cognitive function and apolipoprotein E genotype in a community-dwelling sample of volunteers participating in an ongoing longitudinal program investigating predictors of cognitive decline. NSS were found to be associated with apolipoprotein E (APOE) epsilon4 genotype (p = 0.015), age (p = 0.012) and poor cognitive performance, as assessed by the Mini Mental State Examination (p = 0.053). There was no significant difference between subjects with and without memory complaints in relation to the frequency of NSS (p = 0.130). The association with age and the APOE epsilon4 genotype suggests that the systematic investigation of NSS may contribute to identify subjects at risk of clinically significant cognitive decline in later life.


Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/fisiopatologia , Apolipoproteínas E/genética , Transtornos Cognitivos/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Polimorfismo Genético/genética
3.
Hum Reprod ; 13(6): 1506-13, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9688383

RESUMO

Female cigarette smoking has been implicated as having a detrimental effect on in-vitro fertilization (IVF) outcomes mediated through: (i) a diminished ovarian reserve (DOR), and (ii) an elevated pregnancy loss. Research is sparse regarding the effect of male smoking. The objective of this retrospective cohort study was to investigate the effect of male and female smoking on: (i) the collective quality of embryos selected for uterine transfer, and (ii) the likelihood of achieving an ongoing pregnancy at 12 weeks. A total of 498 consecutive IVF treatment cycles were analysed. Female smokers were significantly younger (P < 0.05) and achieved a better modified cumulative embryo score (mCES) (P < 0.05) than female non-smokers. Female age correlated inversely with the number of oocytes collected (r = -0.42, P < 0.01) and the number of oocytes in turn was important in terms of predicting mCES. The decreasing number of oocytes aspirated with increasing age was of a significantly stronger magnitude for female smokers than for female non-smokers (P < 0.05). Multiple logistic regression was used to determine whether smoking affected the likelihood of achieving a 12-week pregnancy. The mCES, tubal infertility and male smoking were found to be significant. Male smoking interacted with male age (P = 0.0164), indicating for male smokers a decrease of 2.4% in the likelihood of achieving a 12-week pregnancy with every 1-year increase in age. This is the first study to show that male smoking has a deleterious effect on pregnancy outcome among IVF patients. Our study supports the increased risk of DOR but fails to support the elevated incidence of pregnancy loss among female smokers. A reduced pregnancy rate was associated with male smoking possibly through pre-zygotic genetic damage. The growing realization of a paternal component of reproductive impairment suggests that studying the male is necessary.


Assuntos
Fertilização in vitro , Resultado da Gravidez , Fumar/efeitos adversos , Estudos de Coortes , Embrião de Mamíferos/fisiologia , Pai , Feminino , Humanos , Masculino , Gravidez , Estudos Retrospectivos , Fatores de Risco
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