Health Services in China

In the face of the adverse condition of overpopulation, limited resources and technological backwardness shared by the developing nations, at least one country, the People's Republic of China, is attempting to devise a health system which rejects Western standards of medical care and its inherent biases and is geared rather to meet the needs of the local population. This system relies on extensive and often intensive use of traditional practitioners, health teams and medical auxiliaries in an attempt to make health and medical care available to most of China's 80% rural population. By focusing on training and deployment of medical and health personnel, the Chinese are seeking to avoid the burden of large investments in curative medicine accessible only to wealthy urban elites which plagues many other developing countries

The pituitary TGFb1 system as a novel target for the treatment of resistant prolactinomas

Prolactinomas are the most frequently observed pituitary adenomas and most of themrespond well to conventional treatment with dopamine agonists (DAs). However, a subsetof prolactinomas fails to respond to such therapies and is considered as DA-resistantprolactinomas (DARPs). New therapeutic approaches are necessary for these tumors.Transforming growth factor b1 (TGFb1) is a known inhibitor of lactotroph cell proliferationand prolactin secretion, and it partly mediates dopamine inhibitory action. TGFb1 is secretedto the extracellular matrix as an inactive latent complex, and its bioavailability is tightlyregulated by different components of the TGFb1 system including latent binding proteins,local activators (thrombospondin-1, matrix metalloproteases, integrins, among others), andTGFb receptors. Pituitary TGFb1 activity and the expression of different components of theTGFb1 system are regulated by dopamine and estradiol. Prolactinomas (animal models andhumans) present reduced TGFb1 activity as well as reduced expression of several componentsof the TGFb1 system. Therefore, restoration of TGFb1 inhibitory activity represents a noveltherapeutic approach to bypass dopamine action in DARPs. The aim of this review is tosummarize the large literature supporting TGFb1 important role as a local modulator ofpituitary lactotroph function and to provide recent evidence of the restoration of TGFb1activity as an effective treatment in experimental prolactinomasFil: Recouvreux, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Cedars Sinai Medical Center; Estados UnidosFil: Camilletti, María Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Rifkin, Daniel B.. University of New York; Estados UnidosFil: Diaz, Graciela Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentin

Plasminogen Activator in Differentiating Mouse Keratinocytes

The activity of the serine protease plasminogen activator (PA) was measured in cell lysates from primary mouse keratinocyte cultures as well as from a number of established mouse keratinocyte lines. Enzyme activity was generally higher in the transformed lines than in the primary cultures; however, among the lines tested, those that expressed the highest degree of morphologic differentiation had the highest levels of cell-associated PA. In both the normal (primary) and transformed (established) keratinocyte cultures, PA activity increased when cultures reached confluence and morphologic evidence of differentiation was noted. The highest specific activity of the enzyme was found in cells shed from differentiating cultures, which consisted predominantly of detergent-resistant cornified envelopes. As the cultures differentiated and these cells were shed from the culture surface, the total cell-associated PA activity of the culture decreased accordingly. In both the normal and transformed keratinocyte cultures, peak PA activity occurred at a time when DNA synthesis was declining. These findings indicate that as keratinocytes differentiate, their intracellular levels of PA increase. The modulation of this endogenous keratinocyte enzyme may play an important, although as yet undefined, role in the normal maturation and terminal differentiation of these cells

Latent TGF-β binding protein-3 (LTBP-3) requires binding to TGF-β for secretion

AbstractLatent transforming growth factor-β (TGF-β) binding protein (LTBP)-1, which is easily secreted, has been shown to enhance the secretion of TGF-β. Here we show that another member of the LTBP family, LTBP-3, is not secreted by several cell types, but secretion occurs after coexpression with TGF-β. The secretion of LTBP-3 requires complexing of LTBP-3 with Cys33 of the TGF-β propeptide

A Unifying View of Multiple Kernel Learning

Recent research on multiple kernel learning has lead to a number of approaches for combining kernels in regularized risk minimization. The proposed approaches include different formulations of objectives and varying regularization strategies. In this paper we present a unifying general optimization criterion for multiple kernel learning and show how existing formulations are subsumed as special cases. We also derive the criterion's dual representation, which is suitable for general smooth optimization algorithms. Finally, we evaluate multiple kernel learning in this framework analytically using a Rademacher complexity bound on the generalization error and empirically in a set of experiments

Modification of mammalian cell shape: Redistribution of intracellular actin by SV40 virus, proteases, cytochalasin B and dimethylsulfoxide

Pollack and Rifkin describe how different chemical substances alter the morphology of normal cells

PROTEASES PRODUCED BY NORMAL AND MALIGNANT CELLS IN CULTURE

The production of plasminogen activators (PA) is associated with the neoplastic transformation of many types of cells. A number of the phenotypic changes associated with transformation are dependent, at least in part, upon the generation of plasmin by the PA secreted by these cells. One of these changes, the loss of intra­ cellular actin-containing cables in neoplastic cells, can be correlated with the level of extracellular proteases. Moreover, these same proteases can cause the disappear­ ance of actin-containing cables in normal cells when sup­ plied exogenously. Therefore, plasmin acting from the external side of the plasma membrane appears to be cap­ able of causing the dissolution of these intracellular structures, The control of PA synthesis in two cell types, chick embryo fibroblasts infected with a temper­ ature-sensitive mutant of Rous sarcoma virus and human embryonic lung cells, has been examined. Induction of PA requires both RNA and protein synthesis. Deinduction of PA also requires a new RNA and, perhaps, protein to be made. If the synthesis of this RNA is inhibited, PA pro­ duction can continue for many hours under conditions that are normally non-pemissive