RESUMO
p66(shc-/-) mice exhibit prolonged lifespan and increased resistance to oxidative and hypoxic stress. To investigate p66(shc) involvement in human longevity, p66(shc) mRNA and protein were evaluated in fibroblasts from young people, elderly and centenarians, exposed to oxidative or hypoxic stress. Unexpectedly, centenarians showed the highest basal levels of p66(shc). Oxidative stress induced p66(shc) in all samples. At variance, hypoxic stress caused p66(shc) reduction only in cells from centenarians. These changes occurred in absence of any modification of p66(shc) promoter methylation pattern. Intriguingly, in cells from centenarians, p66(shc) induction was affected by p53 codon 72 polymorphism. Thus, cells from centenarians present a peculiar regulation of p66(shc), suggesting that its role in mammalian longevity is more complex than previously thought.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Fibroblastos/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Western Blotting , Células Cultivadas , Códon , DNA/química , DNA/metabolismo , Metilação de DNA , DNA Complementar/metabolismo , Desferroxamina/farmacologia , Desoxirribose/metabolismo , Humanos , Hipóxia , Longevidade , Pessoa de Meia-Idade , Estresse Oxidativo , Regiões Promotoras Genéticas , RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Adaptadoras da Sinalização Shc , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src , Sulfitos/química , Transcrição Gênica , Proteína Supressora de Tumor p53/metabolismoRESUMO
With reference to a case of pregnancy of a patient formerly subjected to tubal sterilization using Pomeroy's technique, the authors define the possibility for tubal stumps to recanalise. Despite the low percentage of failure in tubal sterilization using Pomeroy's technique, the authors conclude that it is advisable to make the earliest possible diagnosis of both intrauterine and extrauterine pregnancy on the basis of suspected symptoms in order to, especially for tubal pregnancies, avoid any tubal sterilization.
PIP: The Pomeroy technique of tubal sterilization is widely used and considered highly effective. Reported in this paper is a case of a pregnancy in a woman from Naples, Italy, who underwent this procedure. The patient requested sterilization during her third cesarean section delivery in 1992 and tubal occlusion was confirmed by a hysterosalpingograph conducted 3 months later. When the patient presented 19 months later with a missed period, an intrauterine pregnancy was found. During the subsequent cesarean section delivery, bilateral tubal exploration revealed that some tubal residual products from the sterilization were still bound by the thread and the stumps graphing. It was assumed that recanalization of the two stumps below the tubal binding was responsible for the conception. A new sterilization was performed after removal of the stumps by the Pomeroy technique 0.5 cm below the canalization.
