The intracellular parasite Leishmania survives and proliferates in host macrophages. In this study we show that parasitophorous vacuoles of L. mexicana gain access to cytosolic material via two different routes.
View Article and Find Full Text PDFBackground: Living donor liver transplantation has gained wide acceptance as an alternative for children with end-stage liver disease. The standard left lateral segment used in this operation does not provide adequate parenchymal mass to broaden its application to larger children or adults.
Methods: We report two cases of adult to adult living donor liver transplantation using a right hepatic lobe in patients with chronic liver disease.
Bone-forming cells are organized in a multicellular network interconnected by gap junctions. In these cells, gap junctions are formed by connexin43 (Cx43) and connexin45 (Cx45). Cx43 gap junctions form pores that are more permeable to negatively charged dyes such as Lucifer yellow and calcein than are Cx45 pores.
View Article and Find Full Text PDFIt is generally assumed that particles > 1 micron elicit a phagocytic response. To determine whether this is the case, we examined the uptake and transport of IgG-opsonized polystyrene beads of defined size, ranging from 0.2 to 3 microns, by mouse bone marrow-derived macrophages.
View Article and Find Full Text PDFJ Bone Miner Res
February 1998
Mechanical loading is essential to maintain skeletal integrity. Because gap junctions in bone are affected by mechanical factors, we studied whether stretch, an anabolic stimulus for osteoblasts, modulates direct intercellular communication in these cells. Gap junctional communication during stretch was assessed using a newly developed method, the "parachute assay," which allows monitoring of dye diffusion without disruption of the plasma membrane.
View Article and Find Full Text PDFPenicillin-resistant Streptococcus pneumoniae (PRP) is of worldwide concern. Treatment failures and fatalities of meningitis caused by PRP have been reported in other locations but not yet in Israel. We describe an 11-month-old infant with meningitis caused by PRP who failed to respond to initial treatment with cefotaxime.
View Article and Find Full Text PDFBackground: The long-term complications of immunosuppressive therapy such as diabetes, hypercholesterolemia, and hypertension are a major source of morbidity in liver transplant recipients. In this prospective, randomized, open-label study we completely withdrew prednisone (PRED) 14 days after liver transplantation in an effort to decrease these metabolic complications. Patients were maintained on mycophenolate mofetil (MMF) in combination with either cyclosporine (CsA; Neoral formulation) or tacrolimus (TAC).
View Article and Find Full Text PDFConnexin43 (Cx43) forms gap junctions that mediate intercellular communication between osteoblasts. We have examined the effects of prostaglandin E2 (PGE2) and parathyroid hormone (PTH) on gap junctional communication in the rat osteogenic sarcoma cells UMR 106-01. Incubation with either PGE2 or PTH rapidly (within 30 min) increased transfer of negatively charged dyes between UMR 106-01 cells.
View Article and Find Full Text PDFMany cells coordinate their activities by transmitting rises in intracellular calcium from cell to cell. In nonexcitable cells, there are currently two models for intercellular calcium wave propagation, both of which involve release of inositol trisphosphate (IP3)- sensitive intracellular calcium stores. In one model, IP3 traverses gap junctions and initiates the release of intracellular calcium stores in neighboring cells.
View Article and Find Full Text PDFIn the CD4+ T cell lineage, two well-defined differentiated populations are the Th1 and Th2 cells, which stem from a common naive T helper precursor (Thp). In this study, we begin to dissect the signaling pathways selectively used by Th1 or Th2 cells as they mature from a common naive precursor in vitro. We show that the maturing Th1 cells mount a vigorous and specific Ca2+ transient upon contact with immunogenic ligand, which is enhanced over that of the naive progenitor cells.
View Article and Find Full Text PDFConnexins are gap junction proteins that form aqueous channels to interconnect adjacent cells. Rat osteoblasts express connexin43 (Cx43), which forms functional gap junctions at the cell surface. We have found that ROS 17/2.
View Article and Find Full Text PDFPhotography or electronic image acquisition is required to document results obtained from staining protein gels with the fluorescent SYPRO dyes. We found that, when using Polaroid type 667 or 57 instant films, the choice of optical filter combination and photographic exposure time strongly influences protein detection sensitivity limits. Ultraviolet light-blocking Kodak Wratten No.
View Article and Find Full Text PDFInsulin-mediated increases in cytosolic calcium are synchronized among the cells in a pancreatic islet, and result in pulsatile secretion of insulin. Pancreatic beta cells express the gap junction protein connexin43 and are functionally coupled, making gap junctional communication a likely mechanism for the synchronization of calcium transients among islet cells. To define the mechanism by which pancreatic islet cells coordinate calcium responses, we studied mechanically-induced intercellular calcium waves in the communication-deficient rat insulinoma cell line RINm5f, and in RINm5f cells transfected with the gap junction protein connexin43.
View Article and Find Full Text PDFWe previously demonstrated that altered peptide ligands (APL) can partially activate T cells, resulting in multiple distinct functional phenotypes, including the induction of anergy. Such APL stimulate a unique pattern of T cell receptor (TCR) phospho-zeta species, and lack associated ZAP-70 kinase activity. While these data suggested that selective signaling pathways downstream of the TCR/CD3 molecules are activated upon APL stimulation, they did not directly demonstrate this.
View Article and Find Full Text PDFWe have further characterized the sensitivity and specificity of SYPRO Orange protein gel stain and SYPRO Red protein gel stain with native and 2-dimensional polyacrylamide gels and for staining gels prior to Western blot analysis. We found that nucleic acids are not stained by the SYPRO protein gel stains, in contrast to results obtained with commonly used silver staining techniques. Bacterial lipopolysaccharides also stain very weakly with SYPRO dyes in comparison to silver staining.
View Article and Find Full Text PDFWe have developed two new fluorescent dyes, SYPRO Orange protein gel stain and SYPRO Red protein gel stain, to detect proteins in electrophoretic gels. Stained protein bands can be excited by ultraviolet light at approximately 300 nm, or at visible wavelengths, with excitation maxima of 472 nm for the Orange stain and 547 nm for the Red stain. Detection can be documented with sensitivity similar to that achieved with silver stain, using standard UV transilluminators and Polaroid 667 black and white film, CCD cameras, or commercially available laser scanners.
View Article and Find Full Text PDFPatients' understanding of discharge teaching is an essential factor for compliance with medications and follow-up care after an organ transplant. This study compared the knowledge gained by the current method of individualized discharge teaching with that same teaching method plus a videotape. Fifty participants were assigned alternately to two groups.
View Article and Find Full Text PDFImmune cells express plasma membrane receptors for extracellular nucleotides. Both G protein-linked metabotropic and channel-forming ionotropic receptors have been described, although no P2 receptor subtype has been cloned from the immune system thus far. Metabotropic receptors have been described in human B but not T lymphocytes; they have not been found in mouse B and T cells.
View Article and Find Full Text PDFAJNR Am J Neuroradiol
October 1995
We report the angiographic appearance of a posterior communicating artery aneurysm with a fistula to the cavernous sinus, which had been misinterpreted as a direct carotid-cavernous fistula, on which endovascular repair was unsuccessfully attempted.
View Article and Find Full Text PDFAnn Otol Rhinol Laryngol Suppl
September 1995
Many cells express multiple connexins, the gap junction proteins that interconnect the cytosol of adjacent cells. Connexin43 (Cx43) channels allow intercellular transfer of Lucifer Yellow (LY, MW = 443 D), while connexin45 (Cx45) channels do not. We transfected full-length or truncated chicken Cx45 into a rat osteosarcoma cell line ROS-17/2.
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