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J W Fries

Publications and source records attributed to J W Fries.

At least 19 recordsLinked to original sources
PubMed1997

N-acetyl cysteine blocks mesangial VCAM-1 and NF-kappa B expression in vivo.

Inducible vascular cell adhesion molecule-1 (VCAM-1) in glomerular mesangial cells (GMC) exposed to lipopolysaccharide (LPS) in vitro involves the activation of nuclear factor-kappa B (NF-kappa B) and its interaction with the proximal VCAM-1 promoter. We used a murine model to assess the effect of the antioxidant, N-acetyl cysteine on GMC activation in vivo. Single intraperitoneal administration of N-acetyl cysteine completely suppressed LPS-induced VCAM-1 expression on the GMC surface. When an oligonucleotide spanning the NF-kappa B binding region of the VCAM-1 promoter was incubated with extracts from the renal cortex of LPS-treated animals, a single nucleoprotein complex formed. This complex was composed of p50 and p65, but not p52, c-Rel, or RelB, and its formation was dramatically inhibited by pretreatment with N-acetyl cysteine, D,L-Buthionine-[S,R]-sulfoximide, a compound that depletes glutathione, augmented VCAM-1 expression inducible with a suboptimal amount of LPS to levels comparable with using 50 micrograms of LPS alone, D,L-Buthionine-[S,R]-sulfoximide also potentiated the p50-p65 binding activity induced with a suboptimal amount of LPS. These data provide a redox-sensitive, transcriptional link between NF-kappa B and VCAM-1 in GMC in vivo and implicate oxidative stress as an important regulatory signal in the pathogenesis of glomerular mesangial cell disorders.

Acetylcysteine↗
PubMed1996

Chondrodysplasia and neurological abnormalities in ATF-2-deficient mice.

Activating transcription factor-2 (ATF-2) is a basic region leucine zipper protein whose DNA target sequence is the widely distributed cAMP response element (CRE). We report here that mice carrying a germline mutation in ATF-2 demonstrated unique actions of ATF-2 not duplicated by other ATF/CREB family members. Mutant mice had decreased postnatal viability and growth, with a defect in endochondral ossification at epiphyseal plates similar to human hypochondroplasia. The animals had ataxic gait, hyperactivity and decreased hearing. In the brain, there were reduced numbers of cerebellar Purkinje cells, atrophic vestibular sense organs and enlarged ventricles. Unlike CREB alpha/delta-deficient mice whose main defect is in long-term potentiation, the widespread abnormalities in ATF-2 mutant mice demonstrate its absolute requirement for skeletal and central nervous system development, and for maximal induction of select genes with CRE sites, such as E-selectin.

Abnormalities, Multiple↗
PubMed1995

Nuclear factor-kappa B mediates induction of vascular cell adhesion molecule-1 in glomerular mesangial cells.

Cultured glomerular mesangial cells (GMCs) can be activated at the transcriptional level by a variety of physiologically relevant factors including cytokines, endotoxin and glycosylated end products. The mechanism with which the signal is transduced from the membrane to the nucleus of these cells is largely unclear. In vascular endothelial cells, the signal transduction pathway involves activation of the pleuripotent transcription factor, NF-kappa B, and leads to increased expression of a variety of genes including vascular cell adhesion molecule-1 (VCAM-1). Here, we demonstrate that TNF-alpha and IL-1 beta transiently induced VCAM-1 mRNA expression in a time dependent manner. TNF-alpha also induced the specific interaction of proteins from GMC nuclei with an oligonucleotide bearing the NF-kappa B binding sites in the VCAM-1 promoter. Electrophoretic mobility shift and supershift analysis indicated that the p65 subunit of NF-kappa B is a component of this induced complex. Finally, reporter activity driven by a VCAM-1 promoter-chloramphenicol acetyltransferase reporter construct increased 8-10 fold following TNF-alpha incubation, or p65 cotransfection. Thus, the p65 subunit of NF-kappa B is activated in GMCs exposed to cytokine and can mediate induction of gene expression.

Animals↗
PubMed1994

Novel cis-acting elements in the human platelet-derived growth factor B-chain core promoter that mediate gene expression in cultured vascular endothelial cells.

Platelet-derived growth factor (PDGF) is a potent mitogen and chemoattractant constitutively expressed by a variety of normal and transformed cells. Transient transfection and deletion analysis of the human c-sis proto-oncogene in cultured vascular endothelial cells revealed a minimal core promoter region extending 82 base pairs upstream from the TATA box. Two novel and functional cis-acting elements were identified within the core that share considerable sequence homology with consensus binding elements for transacting factors of the ETS class and those involved in AP-1 complexes. Deletion or mutation of either the ETS-like site or the AP-1-like site resulted in significant attenuation in the ability of the core to drive transcription. Electrophoretic mobility shift assays revealed that proteins from bovine aortic and human umbilical vein endothelial nuclear extracts bound to these elements in a specific manner and that both sites were essential for protein binding. Ferguson analysis predicted a combined molecular mass of 153 kDa for these proteins. In addition, transient transfection, gel shift, and DNase I footprint analysis were used to identify a functional Sp1 binding site downstream of these elements in the core promoter. By localizing the functional cis-acting elements in the PDGF-B promoter, it may be possible to elucidate the normal transcriptional control of the gene, as well as the mechanisms that activate it in pathologic settings.

Animals↗
PubMed1993

Expression of VCAM-1 and E-selectin in an in vivo model of endothelial activation.

Vascular cell adhesion molecule 1 (VCAM-1) and E-selectin (or endothelial-leukocyte adhesion molecule 1) are inducible endothelial cell adhesion molecules that play a role in the recruitment of leukocytes into sites of inflammation. Information about the spatial and temporal pattern of induced expression of these leukocyte adhesion molecules in vivo is limited. This study reports the expression profile of VCAM-1 and E-selectin in various mouse tissues after lipopolysaccharide administration. Using rat complementary DNA probes for VCAM-1 and E-selectin, Northern blot analysis showed a marked increase in transcript levels for both adhesion molecules in lung, heart, and kidney. Maximal transcript levels for both VCAM-1 and E-selectin were observed at 3-6 hours and declined to low, constitutive levels of expression at 48 hours. Consistent with the Northern blot results, immunoperoxidase analysis revealed focal endothelial cell expression of VCAM-1 in control animals. Following lipopolysaccharide administration, VCAM-1 expression increased dramatically in all vascular beds examined, although the response was heterogeneous. Widespread induced expression of VCAM-1 on cells other than vascular endothelium was not seen. Neither basal nor induced expression correlated with leukocyte adhesion. Signals other than the expression of endothelial leukocyte adhesion molecules are required in vivo for leukocyte infiltration in this murine model of systemic endothelial activation.

Amino Acid Sequence↗
PubMed1992

Nucleotide sequence of rat vascular cell adhesion molecule-1 cDNA.

Vascular cell adhesion molecule 1 (VCAM-1) is an inducible transmembrane protein which is expressed by vascular endothelium following cytokine activation. VCAM-1 mediated the adhesion of certain blood leukocytes and tumor cells via the interaction with its counter-receptor, the integrin VLA4. When initially cloned from interleukin-1 (IL-1) stimulated human umbilical vein endothelial cells, VCAM-1 was reported to contain six immunoglobulin-like domains. However, subsequent cDNA clones and structural analysis of the human gene evealed an alternatively spliced seventh immunoglobulin domain. This seven domain form appears to be the predominant transcript in IL-1 activated endothelium. In this report, the cloning and nucleotide sequence of rat VCAM-1 is described.

Amino Acid Sequence↗
PubMed1991

Gene structure, chromosomal location, and basis for alternative mRNA splicing of the human VCAM1 gene.

Vascular cell adhesion molecule 1 (VCAM-1) is a cell surface glycoprotein adhesive for certain blood leukocytes and tumor cells, which is expressed by activated endothelium in a variety of pathologic conditions including atherosclerosis. Genomic clones encoding the VCAM1 gene were isolated and the organization of the gene was determined. The gene, which is present in a single copy in the human genome, contains 9 exons spanning approximately 25 kilobases of DNA. Exons 2-8 contain C2 or H-type immunoglobulin domains. At least two different VCAM-1 precursors can be generated from the human gene as a result of alternative mRNA splicing events, which include or exclude exon 5. A consensus TATAA element is located upstream of the transcriptional start site. The VCAM1 promoter contains consensus binding sites for NF-kappa B, the GATA family of transcription factors, as well as an AP1 site. The VCAM1 gene was assigned to the 1p31-32 region of chromosome 1 based on the analysis of human-mouse hybrid cell lines and in situ hybridization. Structural analysis of the human VCAM1 gene provides the basis for alternative mRNA splicing and an initial approach to elucidating the regulation of VCAM-1 expression.

Amino Acid Sequence↗
PubMed1991

PDGF B-chain in neurons of the central nervous system, posterior pituitary, and in a transgenic model.

Platelet-derived growth factors (PDGFs) are growth-regulatory molecules that stimulate chemotaxis, proliferation, and increased metabolism of primarily connective tissue cells. In a survey of normal tissues, we found specific immunostaining for PDGF B-chain in neurons, principal dendrites, some axons, and probable terminals throughout the brain, in the dorsal horn of the spinal cord, and in the posterior pituitary of a nonhuman primate (Macaca nemestrina). PDGF activity was extracted from brain cortex and posterior pituitary, and ubiquitous expression of transcripts for the two chains of PDGF and both PDGF receptors was detected throughout the brain and posterior pituitary. A transgenic model was also evaluated in which the chloramphenicol acetyltransferase gene was placed under transcriptional control of the PDGF B-chain promoter. The transgene was preferentially expressed within neural cell bodies in the cortex, hippocampus, and cerebellum. PDGF may act as a neuronal regulatory agent. Neuronal release of PDGF could contribute to nerve regeneration and to glial proliferation that leads to gliosis and scarring.

Animals↗
PubMed1991

Alternative splicing of human VCAM-1 in activated vascular endothelium.

Vascular cell adhesion molecule 1 (VCAM-1)/inducible cell adhesion molecule 110 is a mononuclear leukocyte-selective adhesion molecule, expressed on vascular endothelium following activation by certain cytokines or endotoxin. This inducible transmembrane protein and member of the immunoglobulin gene superfamily was previously reported to contain six immunoglobulinlike domains. Using the polymerase chain reaction, a VCAM-1 cDNA was obtained from mRNA of interleukin-1 (IL-1)-treated cultured human umbilical vein endothelial cells (HUVEC). The cDNA clone contained an additional 276 base-pair (bp) domain, located between domains 3 and 4. This new domain is most homologous to the existing N-terminal domain (domain 1). The internal 276-bp region is encoded by a single exon of the human VCAM-1 gene, indicating that the two forms of mRNA arise by alternative splicing. Both forms of VCAM-1 mRNA were detected by polymerase chain reaction in IL-1-stimulated HUVEC, although the seven-domain form appeared predominant. On the surface of HUVEC only a 110-kd polypeptide, consistent with the seven-immunoglobulinlike domain form of VCAM-1, was detectable by immunoprecipitation. Alternative splicing of the VCAM-1 gene in cytokine-activated endothelium may generate functionally distinct cell-surface adhesion molecules.

Amino Acid Sequence↗
PubMed1990

Genus- and species-specific DNA probes to identify mycobacteria using the polymerase chain reaction.

Differential diagnosis of Mycobacterium tuberculosis, M. avium, and other mycobacteria remains a lengthy process. Recently, the use of DNA probes has been proposed as a new approach for a more specific and rapid diagnosis. Here, we report the cloning and sequencing of a genus-specific probe for Mycobacterium and a species-specific M. avium probe. The genus-specific probe hybridizes with DNA from nine ATCC type strains and 13 isolates of mycobacteria but not to non-mycobacterial DNA. In addition, the cloned fragment could also be amplified by polymerase chain reaction (PCR) in DNa of ten different mycobacterial type strains. The M. avium specific probe hybridizes strongly to sequences amplified in M. avium but not other mycobacterial or non-mycobacterial DNA. Amplification of the target sequence by PCR allowed the detection of 1 fg of all mycobacterial DNA tested for the genus-specific probe and 1 fg of M. avium DNA for the species-specific probe.

Animals↗
PubMed1990

Sequence analysis and amplification by polymerase chain reaction of a cloned DNA fragment for identification of Mycobacterium tuberculosis.

Analysis of the 1,016-base-pair sequence of a putative probe for identification of Mycobacterium tuberculosis revealed two almost identical fragments of 507 and 509 bases. From this sequence two pairs of primers were synthesized (MtbAB and MtbCD), ranging from 18 to 22 nucleotides, for use in polymerase chain reactions (PCRs) with DNA from six reference strains of M. tuberculosis, as well as type strains of M. bovis, M. bovis BCG, M. kansasii, M. avium, M. intracellulare, and M. scrofulaceum. Although there was amplification of DNA from all mycobacterial strains included in the study, when used as probes, a predominant band, fragment CD from M. tuberculosis H37Rv DNA, proved to be more specific for strains of M. tuberculosis than the original probe, pMTb4, was. Amplified fragments from as little as 1 fg of DNA (equivalent to one-fifth of an organism) could be resolved on ethidium bromide-stained gels loaded with a 1/10 volume of PCR. Furthermore, it was possible to amplify specific DNA sequences from frozen M. tuberculosis H37Rv organisms which were thawed prior to PCR.

Base Sequence↗
PubMed1989

Glomerular hypertrophy and epithelial cell injury modulate progressive glomerulosclerosis in the rat.

The effects of glomerular size and visceral epithelial cell integrity upon the development of progressive glomerulosclerosis was studied by superimposing renal ablation on adriamycin-induced nephropathy in rats. Adriamycin alone caused focal epithelial cell injury and proteinuria but minimal segmental glomerulosclerosis. In normal rats, renal ablation was accompanied by mild progressive proteinuria and glomerulosclerosis. However, renal ablation in rats with adriamycin nephropathy caused a dramatic increase in proteinuria and a disproportionately high frequency of segmental glomerulosclerosis. Accelerated glomerular injury after renal ablation in adriamycin-treated rats was associated with substantial glomerular hypertrophy with near doubling of the tuft volume. Morphometric and autoradiographic studies showed that compensatory glomerular hypertrophy occurs without a proportional increase in the number of visceral epithelial cells, leading to a substantial reduction in the density of these cells within the capillary tuft. The severity of segmental glomerulosclerosis showed a significant correlation with the glomerular volume and the reciprocal of the visceral epithelial cell density. Ultrastructural observations indicate that epithelial defects with detachment of the cell processes from the underlying basement membrane are almost invariably seen in areas of segmental glomerulosclerosis with hyalinosis. These findings suggest that the process of progressive glomerulosclerosis is, to a great extent, contingent upon the development of epithelial cell defects, that result from direct injury or from a reduction in the cell density after inordinate compensatory glomerular hypertrophy.

Analysis of Variance↗
PubMed1988

In vivo behavior of murine epidermal cell lines derived from initiated and noninitiated skin.

The in vivo behavior of cell cultures derived from normal and carcinogen-treated mouse epidermis was studied by implanting the cultures in a s.c. vascularized bed protected by a silicone chamber. Cells derived from normal adult mouse epidermis as well as cells derived from tumor-promoter-treated skin were unable to grow in these systems. Conversely, cell lines derived from skin initiated with single doses of N-methyl-N'-nitro-N-nitrosoguanidine or 9,10-dimethyl-1,2-benzanthracene proliferated in these chambers, reforming an epithelial structure. The type of structure in the chambers varied, ranging from formation of almost normal epithelia to atypical invasive behavior. The variable in vivo behavior among the different cell lines may be attributed to the initiation agent, the number of passages of the cultures, random genetic events, the strain of mouse, or a combination of these factors. Most of the cell types used in this study and all the cell lines that were able to grow in these chambers were selected for resistance to Ca-induced terminal differentiation. However, resistance to terminal differentiation according to the Ca2+ switch does not always correlate with the ability to grow in the chambers, since cell lines derived from spontaneous foci of resistance failed to grow in this system. These studies showed some of the possibilities of the SC silicone chambers to study the histogenic potential of cell lines derived from carcinogen-treated epidermis. This system also appears suitable to study the complex relationship between epidermal cells and specialized (dermal) stroma.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1988

Determinants of immune complex-mediated glomerulonephritis.

We have studied the influence of steric factors on the clinico-pathologic expression of immune complex-mediated glomerular diseases, utilizing ferritin as an exogenous antigen. The tracer was planted in the left kidney either in the subepithelial layer of the glomerular capillary wall or on the endothelium and lamina rara interna. Subepithelial immune complex formation resulted in non-inflammatory injury with heterologous and autologous proteinuric phases (115 +/- 16 mg/24 hrs on day 2; 183 +/- 16 mg/24 hrs on day 9) lasting four to five weeks. The glomerular filtration rate of the experimental left kidney was reduced by 19% at day 3, and was increased by 20% at day 12 over right kidney values. Immune complexes persisted for more than seven weeks in the lamina rara externa. In contrast, immune complex deposition on the endothelium and in the lamina rara interna led to acute transient anuria, with a 38% drop in glomerular filtration rate at one hour, massive platelet accumulation, followed by a strong inflammatory response. Proteinuria did not develop. Functional and structural integrity was restored within 24 hours, with complete clearing of immune deposits. We conclude that the distribution of exogenous antigens within the capillary wall determines the structural and functional expression of immune-mediated glomerular diseases.

Animals↗
PubMed1987

Alterations of glomerular podocytic processes in immunologically mediated glomerular disorders.

The importance of the relationship between the alteration of podocytic processes (PP) and proteinuria has been controversial for almost 30 years. In spite of several morphometric studies the range of PP alterations in different proteinuric conditions has gone unnoticed. Thus, we studied the distribution of abnormally broadened PP in different glomerulopathies and in normal controls (children and adults). We found a highly variable mean PP-width in all proteinuric patients, values that were, however, always clearly distinct from normal controls in children and adults. A correlation between the extent of PP alteration and the amount of proteinuria was not found (r = 0.09) for the group as a whole or for the different clinico-pathological entities. In proteinuric patients 15 to 50% of all PP were broadened and covered 40 to 60% of the total length of the peripheral capillary loop. We conclude that the alteration of PP in various proteinuric conditions is variable and does not correlate with the level of proteinuria. These studies further suggest that other mechanisms, possible hemodynamic adaptation in response to the capillary wall injury, might play a role in the permeability changes observed in these patients.

Adult↗