Parathyroid Hormone Hormone-Related Protein and the PTH Receptor Regulate Angiogenesis of the Skin

In developing organs, parathyroid hormone (PTH)/parathyroid hormone-related protein (PTHrP) receptor (PPR) signaling inhibits proliferation and differentiation of mesenchyme-derived cell types resulting in control of morphogenic events. Previous studies using PPR agonists and antagonists as well as transgenic overexpression of the PPR ligand PTHrP have suggested that this ligand receptor combination might regulate the anagen to catagen transition of the hair cycle. To further understand the precise role of PTHrP and the PPR in the hair cycle, we have evaluated hair growth in the traditional K14-PTHrP (KrP) and an inducible bitransgenic PTHrP mice. High levels of PTHrP trangene expression limited to the adult hair cycle resulted in the production of shorter hair shafts. Morphometric analysis indicated that reduced proliferation in the matrix preceded the appearance of thinner hair follicles and shafts during late anagen. CD31 staining revealed that the late anagen hair follicles of the KrP mice were surrounded by reduced numbers of smaller diameter capillaries as compared to controls. Moreover, the fetal skins of the PTHrP and PPR knockouts (KOs) had reciprocal increases in the length, diameter, and density of capillaries. Finally, crossing the KrP transgene onto a thrombospondin-1KO background reversed the vascular changes as well as the delayed catagen exhibited by these mice. Taken together, these findings suggest that PTHrP's influence on the hair cycle is mediated in part by its effects on angiogenesis

Matrix Rigidity Induces Osteolytic Gene Expression of Metastatic Breast Cancer Cells

Nearly 70% of breast cancer patients with advanced disease will develop bone metastases. Once established in bone, tumor cells produce factors that cause changes in normal bone remodeling, such as parathyroid hormone-related protein (PTHrP). While enhanced expression of PTHrP is known to stimulate osteoclasts to resorb bone, the environmental factors driving tumor cells to express PTHrP in the early stages of development of metastatic bone disease are unknown. In this study, we have shown that tumor cells known to metastasize to bone respond to 2D substrates with rigidities comparable to that of the bone microenvironment by increasing expression and production of PTHrP. The cellular response is regulated by Rho-dependent actomyosin contractility mediated by TGF-ß signaling. Inhibition of Rho-associated kinase (ROCK) using both pharmacological and genetic approaches decreased PTHrP expression. Furthermore, cells expressing a dominant negative form of the TGF-ß receptor did not respond to substrate rigidity, and inhibition of ROCK decreased PTHrP expression induced by exogenous TGF-ß. These observations suggest a role for the differential rigidity of the mineralized bone microenvironment in early stages of tumor-induced osteolysis, which is especially important in metastatic cancer since many cancers (such as those of the breast and lung) preferentially metastasize to bone

ACC/AHA/ASE 2003 Guideline Update for the Clinical Application of Echocardiography: Summary Article: A Report of the American College of Cardiology/American HeartAssociation Task Force on Practice Guidelines (ACC/AHA/ASE Committee to Update the 1997 Guidelines for the Clinical Application of Echocardiography)

"The previous guideline for the use of echocardiography was published in March 1997. Since that time, there have been significant advances in the technology of echocardiography and growth in its clinical use and in the scientific evidence leading to recommendations for its proper use. Each section has been reviewed and updated in evidence tables, and where appropriate, changes have been made in recommendations. A new section on the use of intraoperative transesophageal echocardiography (TEE) is being added to update the guidelines published by the American Society of Anesthesiologists and the Society of Cardiovascular Anesthesiologists. There are extensive revisions, especially of the sections on ischemic heart disease; congestive heart failure, cardiomyopathy, and assessment of left ventricular (LV) function; and screening and echocardiography in the critically ill. There are new tables of evidence and extensive revisions in the ischemic heart disease evidence tables. Because of space limitations, only those sections and evidence tables with new recommendations will be printed in this summary article. Where there are minimal changes in a recommendation grouping, such as a change from Class IIa to Class I, only that change will be printed, not the entire set of recommendations. Advances for which the clinical applications are still being investigated, such as the use of myocardial contrast agents and three-dimensional echocardiography, will not be discussed.

Paris universal exposition MDCCCLXXVIII. The catalogue of the United States collective exhibition of education,

Half-title: United States exhibition of education.Prefatory note.--Statement of the theory of education in the United States.--Statistical summaries from the Annual report of the United States commissioner of education for the year 1876.--Official scheme of the educational exposition.--Catalogue of exhibits: 1. United States bureau of education. 2. Alphabetical list.--Appendix: 1. Circular issued in preparing the exhibition. 2. Extract from the Report of the commissioner of education for 1876.Mode of access: Internet

Morphology and development of the gynoecium in Centrolepidaceae: The most remarkable range of variation in Poales

This paper explores the relative impacts of reduction and polymerization on the evolution of reproductive structures in the small but morphologically diverse family Centrolepidaceae. Centrolepidaceae are closely related to Restionaceae and belong to the large order Poales, which also includes the grasses. In the largest genus of Centrolepidaceae, Centrolepis, the reproductive structures are viewed either as highly unusual aggregations of reduced flowers (the pseudanthial interpretation) or as unique flowers evolved through extreme reduction in the androecium, usually accompanied by a drastic increase in carpel number and elaboration of the entire gynoecium. Comparative data are here presented on gynoecia of all three genera of Centrolepidaceae; these data strongly support the latter (euanthial) interpretation. The combined phenomenon of carpel multiplication and decrease in stamen number is unexpected in a predominantly wind-pollinated lineage. Applying a pseudanthial interpretation would create a considerable morphological gap with reproductive structures of other Poales, whereas accepting a euanthial concept allows an almost continuous morphological series with related taxa

Ciência, técnica e as expedições da marinha de guerra norteamericana, U.S. Navy, em direção à América Latina (1838-1901) Science, techniques, and U.S. naval expeditions toward Latin America (1838-1901)

Este artigo tem por objetivo mapear as expedições realizadas pela U. S. Navy - a marinha de guerra dos Estados Unidos - em direção à América Latina, no século XIX. Foram realizadas doze viagens no período, mostrando o interesse norte-americano pela região desde a década de 1830.<br>This article focuses on U.S. Navy expeditions set a course from United States to Latin America in nineteenth century. Twelve expeditions as a whole were accomplished in that period, showing the American concern in that region, since 1830 decade