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Sickle cell disease (SCD) is the most prevalent inherited monogenic pathology in South America. Although children with SCD have normal birthweight, weight deficit is often seen from early childhood. On the other hand, paradoxically, normal final height associated with delayed puberty has been reported from Brazil and Jamaica. This cross-sectional study describes the growth pattern by age and sex in 76 children and adolescents with SCD in Sergipe, north-east Brazil with a median age of 110 months. Median weights and heights for age were below the NCHS standards. The weight and height deficits were statistically significant for boys of all ages, except for 7-year-olds. Most girls have median weights and heights below the NCHS standards but this only becomes statistically significant at 15 years of age. Family channels were calculated from the parents' heights. The observed height was lower than the expected percentile value for the family in seven (41%) children, equal to expected family height in six (35%) and above expected family height in four (24%) of 17 teenagers. Our findings suggest that Brazilian children with SCD do not attain normal height and weight. It is therefore likely that, although maximum height and weight velocity occur significantly later than normal due to delayed puberty, the magnitude of this spurt is less than normal. [ABSTRACT FROM AUTHOR]

Background: Estrogen receptors occur in about two-thirds of breast tumors and endocrine therapy is probably the most important systemic therapy for hormone receptor positive breast cancer. However, after an initial response to hormonal therapy, most tumors develop resistance leading to disease progression. Central mechanisms thought to be involved in this process include: 1) alterations in tumor cell physiology causing insensitivity to drug-induced apoptosis or induction of drug-detoxifying mechanisms; 2) expression of energy-dependent transporters that eject anti-cancer drugs from cells and 3) the emergence of cancer stem-like cell clones that are estrogen-independent and/or antiestrogen resistant. We and others have shown that Notch signaling mediates survival signals in ER+ breast cancer cells; induces expression of drug transporter ABCG2 (BCRP), activates ERa in the absence of estrogen and mediates survival of breast cancer stem-like cells. Previously, we demonstrated a crosstalk between ERa and Notch signaling whereby estrogen inhibits Notch activation and estrogen withdrawal ortamoxifen re-activate Notch, a possible mechanism of resistance. The mechanism of these effects has remained elusive. Methods: we used sub-cellular fractionation and immunofluorescence staining to investigate the total expression and cellular distribution of Notch signaling components in MCF-7 cells treated with 17-p-estradiol, or estrogen-free medium. Results: Our data shows that in cells treated with estrogen-free medium, Notchi is located in the Lipid Rafts (LR) in the plasma membrane, along with Notch signaling components such as presenilin 1 (the catalytic subunit of γ-secretase), ADAM10 and Notch negative regulator NUMB. There is published evidence that γ-secretase is most active in lipid rafts. 17-p-Estradiol modifies the membrane lipid composition and change the localization of Notch and Notch regulators (such as ADAM10, presenilin-1 and NUMB) at the plasma membrane, thereby altering the activation of Notch. These observations are consistent with a model in which the lipid composition of the plasma membrane is a critical factor in regulating the rate of Notch activation. FDA-approved cholesterol lowering drugs affect Notch signaling in ways consistent with this model. Conclusions: Our findings indicate that endocrine therapy affects Notch signaling at least in part through alterations in membrane composition and lipid raft localization of Notch signaling components. [ABSTRACT FROM AUTHOR]