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41.
Bruce E. Lewis Colin Sumida Ming H. Hwang Henry S. Loeb 《Catheterization and cardiovascular interventions》1992,26(4):295-299
Four selected cases of emergent IABP insertion in PV patients are presented. After angiographic documentation of critical iliac stenosis, conservative peripheral angioplasty was performed prior to IABP insertion. No patient experienced a peripheral ischemic event associated with IABP use. © 1992 Wiley-Liss, Inc. 相似文献
42.
GillibertDuplantier J Neaud V Desmoulière A BioulacSage P Rosenbaum J 《Wound repair and regeneration》2005,13(1):A19-A19
Scarring of the cornea, the transparent tissue at the front of the eyeball, is an important cause of visual impairment. A major chemokine upregulated in tear fluid after corneal injury is platelet‐derived growth factor (PDGF), which induces the stromal cells of the cornea (keratocytes) to assume a fibroblastic phenotype. We have investigated the role of PDGF in matrix contraction by human corneal fibroblasts (HCF) using the standard three‐dimensional (3D) fibroblast‐populated collagen matrix model (FPCM).
When stimulated with PDGF, HCF in monolayer (2D) display circular ruffles (CR) on their dorsal surface. Using immunolabeling, we found that CR contain proteins of the Arp2/3 complex, which is required for the assembly of filamentous actin during protrusive activity. This PDGF‐mediated ruffling ability is altered by antibodies or blocking peptides that specifically interfere with the Arp2/3‐mediated pathway of actin polymerization, as well as by the myosin light chain kinase inhibitor, ML9. Preincubation with anti‐PDGF‐BB antibody or with the tyrosine kinase inhibitor, AG1295, also inhibits CR. While PDGF efficiently stimulates HCF‐mediated cell protrusive activity and macroscopic collagen gel contraction in the 3D model, this effect is directly inhibited by all the substances which inhibit CR in 2D, demonstrating a direct involvement of the PDGF‐mediated CR pathway in tissue contraction. Thus, 3D PDGF‐induced matrix contraction by HCF involves the same players as CR, a phenomenon observed in 2D cell cultures: PDGF‐BB receptor, receptor tyrosine kinase, the machinery for filamentous actin assembly (Arp 2/3 complex, Scar and Wasp proteins), and myosin. The functional role of circular ruffling or its equivalent in three‐dimensional fibroblast‐populated collagen matrices seems to be a rapid reorganization of the actin cytoskeleton in preparation for cell‐matrix interaction. 相似文献
When stimulated with PDGF, HCF in monolayer (2D) display circular ruffles (CR) on their dorsal surface. Using immunolabeling, we found that CR contain proteins of the Arp2/3 complex, which is required for the assembly of filamentous actin during protrusive activity. This PDGF‐mediated ruffling ability is altered by antibodies or blocking peptides that specifically interfere with the Arp2/3‐mediated pathway of actin polymerization, as well as by the myosin light chain kinase inhibitor, ML9. Preincubation with anti‐PDGF‐BB antibody or with the tyrosine kinase inhibitor, AG1295, also inhibits CR. While PDGF efficiently stimulates HCF‐mediated cell protrusive activity and macroscopic collagen gel contraction in the 3D model, this effect is directly inhibited by all the substances which inhibit CR in 2D, demonstrating a direct involvement of the PDGF‐mediated CR pathway in tissue contraction. Thus, 3D PDGF‐induced matrix contraction by HCF involves the same players as CR, a phenomenon observed in 2D cell cultures: PDGF‐BB receptor, receptor tyrosine kinase, the machinery for filamentous actin assembly (Arp 2/3 complex, Scar and Wasp proteins), and myosin. The functional role of circular ruffling or its equivalent in three‐dimensional fibroblast‐populated collagen matrices seems to be a rapid reorganization of the actin cytoskeleton in preparation for cell‐matrix interaction. 相似文献
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45.
Van Buskirk Glenn A. González Mario A. Shah Vinod P. Barnhardt Scott Barrett Colin Berge Stephen Cleary Gary Chan Keith Flynn Gordon Foster Thomas Gale Robert Garrison Raymond Gochnour Scott Gotto Amanda Govil Sharad Gray Vivian A. Hammar James Harder Samuel Hoiberg Charles Hussain Ajaz Karp Carol Llanos Hector Mantelle Juan Noonan Patrick Swanson David Zerbe Horst 《Pharmaceutical research》1997,14(7):848-852
Pharmaceutical Research - 相似文献
46.
Colin T Myers 《Emergency medicine Australasia : EMA》1996,8(Z1):51-56
Large volume fluid resuscitation attempting to normalise physiological parameters in hypovolaemic shock has become the accepted management practice during the last 30 years. This doctrine, based on research in the 1950s, teaches that shock increases mortality, aggressive resuscitation improves outcome and normalisation of vital signs protects against multiple organ dysfunction. The wide acceptance of this doctrine is demonstrated by the central role it plays in the American College of Surgeons Advanced Trauma Life Support (ATLS) course and its Australian equivalent the Early Management of Severe Trauma (EMST) course. During the late 1980s, a number of animal research papers demonstrated severe limitations to the earlier work performed in the 1950s and proposed an alternative approach using hypotense or minimal fluid resuscitation. Controlled haemorrhagic shock is hypovolaemic shock in which the source of the bleeding is easily controlled without operation and hence aggressive fluid resuscitation can be pursued with minimum risk. Uncontrolled haemorrhagic shock is hypovolaemic shock due to bleeding which cannot be controlled without surgery. The restoration of blood pressure towards normal levels may lead to dislodgement of thrombus and loss of vascular spasm in damaged vessels, with a subsequent increase in blood loss. It is in this situation that hypotense resuscitation is thought to be of most value. Hypotense resuscitation is defined as the use of fluid resuscitation to maintain blood pressure at lower than normal levels which are sufficient to maintain life, but minimise the risk of exacerbating internal bleeding. Prompted by animal research a number of human studies have been undertaken to clarify the role of fluid resuscitation in uncontrolled haemorrhage. At present, there is wide acceptance of the use of hypotense or minimal volume resuscitation for ruptured abdominal aortic aneurysm and a recent demonstration that morbidity and mortality are decreased by the use of hypotense resuscitation in penetrating truncal trauma. There are however many other clinical situations that may produce uncontrolled haemorrhagic shock about which we have little clinical data to predict appropriate levels of fluid resuscitation. These include ectopic pregnancy, gastro-intestinal haemorrhage and blunt multi-system trauma. This paper will analyse the animal studies that demonstrate the physiological effects of the various fluid resuscitation regimes and discuss all the clinical papers on the subject of hypotense resuscitation. An attempt will then be made to integrate this data into current Australian practice and give broad guidelines on the modern management of uncontrolled haemorrhagic shock, based on minimal volume or hypotense resuscitation. 相似文献
47.
Carmelo Romano Michael A. Sesma Colin T. McDonald Karen O'malley Anthony N. van den Pol John W. Olney 《The Journal of comparative neurology》1995,355(3):455-469
The receptor mGluR5 is a metabotropic glutamate receptor with messenger RNA abundantly present throughout cortex, hippocampus, and caudate/putamen that is also coupled to phosphatidyl inositide hydrolysis and calcium mobilization. In this study, the distribution of mGluR5 was examined in rat brain by immunocytochemistry. The antibody utilized is highly specific and does not cross react with the most closely related other metabotropic glutamate receptor, as determined by Western blot analysis of nonneuronal cells transfected with metabotropic receptor coding sequences. The receptor mGluR5 is widely expressed with the highest density in olfactory bulb, caudate/putamen, lateral septum, cortex, and hippocampus, as confirmed with both immunocytochemistry and Western blot analysis. Electron microscopic studies in hippocampus and cortex indicate that the labeling is mostly on membranes of dendritic spines and shafts. Light and electron microscopic evidence indicates that some mGluR5 immunoreactivity is located in presynaptic axon terminals, suggesting that mGluR5 may function as a presynaptic receptor. 相似文献
48.
Rajabi-Siahboomi Ali R. Bowtell Richard W. Mansfield Peter Davies Martyn C. Melia Colin D. 《Pharmaceutical research》1996,13(3):376-380
Purpose. The purpose of this study was to characterise the water mobility in the gel layer of hydrating HPMC tablets. Water mobility in the gel layer of different HPMCs was studied.
Methods. NMR imaging, a non-invasive technique, has been used to measure the spatial distribution of self-diffusion coefficient (SDC) and T2 relaxation times across the gel layer.
Results. It has been shown that there is a water mobility gradient across the gel layer of HPMC tablets. Although SDC and T2 relaxation times in the outer parts of the gel layer approached that of free water, in the inner parts they decreased progressively. Water mobility and SDC in the gel layer of different HPMCs appeared to vary with degree of substitution of the polymer and the lowest values were obtained across the gel layer of K4M tablets.
Conclusions. Water mobility varies across the gel layer of hydrating HPMC tablets and it is dependent on the degree of substitution of the polymer. 相似文献
49.
D Goossens V Bony P Gane Y Colin J-P Cartron 《Transfusion Clinique et Biologique》2006,13(1-2):164-166
Mice carrying inactivated Rh and Rhag genes were generated by insertional targeting. KO animals exhibited normal growth, development and fertility and both types were indistinguishable at a gross phenotypic level from their wild type littermates. Preliminary analysis revealed that red cells from Rh-/- mice lack Rh protein and have a moderate decrease of Rhag protein, whereas those from Rhag-/- mice have a total absence of Rhag and Rh proteins. Studies are in progress to delineate the antigenic, biochemical and functional abnormalities of red cells from these animals as well as the impact on hematological parameters and erythropoiesis. 相似文献
50.
Colin Pritchard 《International journal of geriatric psychiatry》1992,7(2):125-134
Between 1974 and 1987 there were increases overall in male suicide rates in the USA, with the greatest increases among elderly men. While female suicide levels overall fell in the USA, elderly female suicide rates failed to show the same improvement. Compared with the rest of the western world, suicide rates for elderly people in the USA were among the worst. Suicide was far more prevalent than homicide, but this is not reflected in the media, where homicide is given a high profile but where there is relative silence surrounding suicide among elderly people. 相似文献