Skeletal growth: A major determinant of bone's structural diversity in women and men

Skeletal fragility in advanced age has its antecedence in growth because the variance in bone traits achieved during growth is an order of magnitude greater than rates of loss during aging. Factors modifying skeletal morphology such as exercise and nutrition are likely to be best during growth. At puberty, appendicular growth decelerates while axial growth accelerates. Sex differences in bone length, width, mass, and strength emerge largely during puberty. In late puberty, there is slowing of longitudinal bone growth. The effects of illness during growth depend on the maturational stage at the time of disease exposure, not just the “severity” of the illness. In particular, growth of the distal radius is more rapid at the distal metaphysis, and at this site the longitudinal growth outpaces bone formation upon the surfaces of trabeculae emerging from the growth plate, delaying their coalescence

Immunoexpression of cleaved caspase-3 shows lower apoptotic area indices in lip carcinomas than in intraoral cancer

ABSTRACT Objective This study aimed to evaluate apoptosis by assessing cleaved caspase-3 immunoexpression in hyperplastic, potentially malignant disorder (PMD), and malignant tumors in intraoral and lower lip sites. Material and Methods A retrospective study using paraffin blocks with tissues from patients with inflammatory fibrous hyperplasia (IFH), actinic cheilitis, oral leukoplakia, lower lip and intraoral squamous cell carcinoma (SCC) was performed. The tissues were evaluated by immunohistochemical analysis with anti-cleaved caspase-3 antibody. Apoptotic area index was then correlated with lesion type. Results From 120 lesions assessed, 55 (46%) were cleaved caspase-3-positive. The SCC samples (n=40) had the highest apoptotic area indices (n=35; 87.5%). Significant differences were detected between SCCs and PMDs (p=0.0003), as well as SCCs and IFHs (p=0.001), regarding caspase-3 immunopositivity. Carcinomas of the lower lip had lower apoptotic area indices than intraoral cancer (p=0.0015). Conclusions Cleaved caspase-3 immunoexpression showed differences in oral SCCs and PMDs and demonstrated a distinct role of apoptosis in carcinogenesis of intraoral and lower lip cancer. In future, the expression of cleaved caspase-3 with other target molecules in oral cancer may be helpful in delineating the prognosis and treatment of these tumors