University of Texas Southwestern Medical Center

About: University of Texas Southwestern Medical Center is a healthcare organization based out in Dallas, Texas, United States. It is known for research contribution in the topics: Population & Cancer. The organization has 39107 authors who have published 75242 publications receiving 4497256 citations. The organization is also known as: UT Southwestern & UT Southwestern Medical School.

Effect of testosterone and estradiol in a man with aromatase deficiency.

Abstract: Recent reports of disruptive mutations of the genes for the estrogen receptor or for cytochrome P-450 aromatase1–6 have shed new light on the role of estrogen. In females the lack of estrogen due to aromatase deficiency leads to pseudohermaphroditism and progressive virilization at puberty, whereas in males pubertal development is normal. In members of both sexes epiphyseal closure is delayed, resulting in a eunuchoid habitus, and osteopenia is present.6 These findings suggest a crucial role of estrogen in skeletal maturation.1–6 We describe the responses to androgen and estrogen in a man with a novel, homozygous inactivating mutation of . . .

Pervasive roles of microRNAs in cardiovascular biology

Abstract: First recognized as regulators of development in worms and fruitflies, microRNAs are emerging as pivotal modulators of mammalian cardiovascular development and disease. Individual microRNAs modulate the expression of collections of messenger RNA targets that often have related functions, thereby governing complex biological processes. The wideranging functions of microRNAs in the cardiovascular system have provided new perspectives on disease mechanisms and have revealed intriguing therapeutic targets, as well as diagnostics, for a variety of cardiovascular disorders.

The LDL Receptor

Abstract: In this article, the history of the LDL receptor is recounted by its codiscoverers. Their early work on the LDL receptor explained a genetic cause of heart attacks and led to new ways of thinking about cholesterol metabolism. The LDL receptor discovery also introduced three general concepts to cell biology: receptor-mediated endocytosis, receptor recycling, and feedback regulation of receptors. The latter concept provides the mechanism by which statins selectively lower plasma LDL, reducing heart attacks and prolonging life.

Fibroblasts, myofibroblasts, and wound contraction

Abstract: clinical case reconstructed by Guido Majno (1975) from the Hippocratic records describes a wrestler who visits the iatreion (out-patient clinic) to be treated for a shoulder dislocation. With less invasive procedures no longer working to tighten the dislocation, the clinic adopts the drastic measure of inducing wound contraction by poking a hot needle through the skin of the armpit, and \"in this way the cavity, into which the humerous is mostly displaced, is best scarred over and cut off\" In Greek medicine circa 400 B.C.E., familiarity with wound contraction after burn injury already was commonplace. Closure of cutaneous wounds involves three processes: epithelization, connective tissue deposition, and contraction. The contribution of each process varies according to the type of wound. In general, epithelization results in resurfacing of the wound; connective tissue deposition results in replacement of damaged dermis; and contraction brings the margins of open wounds together (Peacock, 1984; Clark, 1988; Mast, 1992). In mammals with loose skin (meaning loosely attached to the underlying tissue layer), wound contraction leads to wound closure with little scarring or loss of function. In humans, whose skin is more firmly attached to underlying tissues, the consequences of contraction are less beneficial, ranging from minimal cosmetic scar in some cases to loss of joint motion or major body deformation in others. Consequently, a distinction has been made between contraction as a normal process of wound closure, and contracture as the abnormal result of the contraction process where signifcant scarring or loss of function occurs (Hunt and Dunphy, 1979). The pathologic consequences of tissue contraction include a variety of conditions ranging from contracture of the fibrous capsule surrounding breast implants to constricture of hollow organs (e.g., the esophagus) after injury (Skalli and Gabbiani, 1988; Rudolph et al., 1992). In contemporary cell biology, research on wound contraction focuses on the wound fibroblast. Skin fibroblasts normally are sessile and quiescent, but shortly after cutaneous wounding, they become activated. Activated fibroblasts migrate to the fibronectin-fibrin wound interface, proliferate, and synthesize a new collagen-containing matrix called granulation tissue. Around the same time, wound contraction begins. Once the wound defect is replaced, the expanded fibroblast population stops dividing and regresses and extracellular matrix remodeling commences (Peacock, 1984; Clark, 1993). Despite the importance of wound contraction for wound