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J C Jones

Publications and source records attributed to J C Jones.

At least 91 records · Page 5Linked to original sources
PubMed1993

Immunoglobulin heavy chain constant and heavy chain variable region genes in phylogenetically diverse species of bony fish.

Genomic DNA from 18 phylogenetically diverse species of bony fish was hybridized with probes specific for the channel catfish immunoglobulin heavy chain constant (CH) gene, as well as with immunoglobulin heavy chain variable (VH) probes specific for five channel catfish VH gene families. The results showed that CH probes strongly hybridized only to genomic fragments from other catfish species. In contrast, restricted DNA from most other species hybridized with at least two channel catfish VH probes. In those species whose DNA hybridized with multiple VH probes, the restriction pattern of hybridizing fragments was probe-dependent. These studies suggest that (1) the CH gene defined in channel catfish appears to share similarity only with CH genes in other catfish species, (2) families of VH genes appear to have diverged in early phylogenetic lineages of teleosts, and (3) VH genes similar to those defined in catfish appear to be widely represented in phylogenetically diverse species of teleosts.

Animals↗
PubMed1993

Paraneoplastic syndromes associated with lung cancer.

Paraneoplastic syndromes are caused by systemic factors that are produced at a site distant from the primary tumor or its metastases. Although these syndromes can be observed in a variety of tumor types, they are commonly found in lung cancer, particularly small cell lung cancer. In this review, we focus on recent advances in the diagnosis and treatment of two of the more well-documented paraneoplastic syndromes--endocrinologic and neurologic systemic manifestations of cancer.

Endocrine System Diseases↗
PubMed1993

The matrix secreted by 804G cells contains laminin-related components that participate in hemidesmosome assembly in vitro.

Hemidesmosomes are important adhesion devices found in epithelial cells. They connect the intermediate filament cytoskeleton network with components of the basement membrane zone. 804G cells are an unusual epithelial cell line, since they form bona fide hemidesmosomes when plated on glass or plastic. In this study we tested an hypothesis: that this ability is a consequence of an extracellular component produced by the 804G cells. As probes for our study we generated a rabbit antiserum (J18) and monoclonal antibodies against components of urea-solubilized 804G matrix. Antibodies in the J18 serum recognize major lectin-binding polypeptides of 150, 140 and 135 kDa in the 804G matrix. A monoclonal antibody (5C5) that shows reactivity with the 150 and 135 kDa polypeptides in western immunoblots immunoprecipitates all three molecular mass species, indicating that these polypeptides are part of a matrix complex. Moreover, one, at least, of these matrix elements is immunologically related to laminin, since J18 antibodies selected on fusion protein fragments of a newly characterized laminin variant, laminin B2t (Kallunki et al., J. Cell Biol., 119, 679-694, 1992), react with the 140 kDa polypeptide component of the 804G cell matrix. To undertake functional analyses of 804G matrix, cells of the human epidermal carcinoma line SCC12, which do not assemble bona fide hemidesmosomes in vitro, were cultured on 804G matrix for 24 h and then analysed by confocal immunofluorescence and electron microscopy. In SCC12 cells maintained on 804G cell matrix, hemidesmosomal antigens localize in a distinctive leopard spot pattern that mirrors the distribution of 804G matrix elements. Furthermore, ultrastructural analysis reveals that the 804G cell matrix supports the formation of 'mature' hemidesmosomes by SCC12 cells. Thus 804G cell matrix is a remarkable tool for hemidesmosome studies and it will now be of great importance to determine the exact composition of the 804G matrix, especially its structural and antigenic relationship to laminins.

Animals↗
PubMed1993

Marginal sealing ability of four restorative materials placed in root surfaces.

The sealing ability of four restorative materials, placed in root surface cavities, was assessed by a range of standard in vitro microleakage tests. The rank order of the severity of microleakage associated with the four materials varied with the different tests. Although differences between the performance of unlined amalgam, two different dentine-bonded composites and a glass-ionomer restorative material were detected, most were not statistically significant. None of the materials tested completely eliminated microleakage and so even those materials reported to be adhesive to dentine cannot be considered ideal in the restoration of root surface cavities.

Composite Resins↗
PubMed1992

The role of the basement membrane in differential expression of keratin proteins in epithelial cells.

Extracellular matrix is considered to play an important role in determining the phenotype of cells with which it interacts. Here we have investigated the possibility that extracellular matrix is involved in specifying the pattern of keratin expression in epithelial cells. For these studies, we have developed an explant system in which epithelial cells from one type of stratified epithelial tissue, namely conjunctiva, are maintained on an extracellular matrix substrate derived from a different tissue, namely cornea. These ocular tissues are ideal for such analyses since they express distinct sets of keratins. For example, bovine conjunctival epithelium processed for immunofluorescence is not recognized by antibody preparations against keratin K3 or K12. In contrast, K3 and K12 antibodies generate intense staining in bovine corneal epithelium. At the immunochemical level, conjunctival cells in situ appear to possess no K12 and only trace amounts of K3, whereas corneal epithelial cells in situ possess both K3 and K12. When conjunctival cells are maintained on a corneal substrate with an intact basement membrane for 10 days in vitro they begin to express keratin K12 as determined by immunofluorescence. On the other hand, conjunctival cells that are maintained on a corneal substrate lacking a basement membrane fail to show staining with K12 antibodies. Conjunctival cells begin to show intense staining using K3 antibodies within about 10 days of being placed in culture regardless of their substrate. These results indicate that basement membrane can play a positive role in determining cell-specific expression of certain keratins such as K12. However, other keratins such as K3 may be "unmasked" and/or their expression may be upregulated simply by placing conjunctival epithelial cells in culture. We speculate that in conjunctiva K3 expression is influenced by certain negative exogenous factors. We discuss the possible means of regulation of keratin expression in our model system.

Animals↗
PubMed1992

A comparison of four in vitro marginal leakage tests applied to root surface restorations.

Marginal leakage associated with a variety of restorative materials, placed in root surface cavities of extracted teeth, was assessed by immersing the teeth in either acidified gelatin, eosin dye, silver nitrate or a solution of radiocalcium. The allocation of a score, dependent on the depth of tracer penetration at the interface, allowed comparisons to be made between the leakage tests employed. The rank order of the four leakage tests was generally consistent. Eosin resulted in the most severe leakage, followed by silver nitrate and radiocalcium, whilst acidified gelatin was the least sensitive method for demonstrating marginal leakage. Differences in leakage scores were not, however, always statistically significant. None of the four tests investigated was ideal, although eosin dye was considered to be the most appropriate method of demonstrating marginal leakage associated with root restorations.

Calcium Radioisotopes↗
PubMed1992

Restricted tissue distribution of a 37-kD possible adherens junction protein.

A major polypeptide of M(r) 37,000 was purified from a desmosome-enriched citric acid-insoluble pellet of pig tongue epithelium. The polypeptide was solubilized from the 4-M urea-insoluble pellet with 9 M urea, and extracts were separated by carboxymethyl cellulose and gel filtration chromatography. The 37-kD protein was obtained in milligram quantities as a single band on two-dimensional gels in 30% yield after 21-fold purification from the citric acid-insoluble fraction. The protein is not glycosylated and has a pI of approximately 8.7. Although isolated from a fraction rich in desmosomes, the 37-kD protein is not a desmosomal protein. Indirect immunofluorescence analysis of frozen sections of tongue and other tissues demonstrated that antibodies raised to the 37-kD protein bound only to suprabasal cell layers at punctate regions of the periphery of the cell and was absent from most regions of epidermis, whereas antibodies to desmoplakins I and II, desmosomal proteins, bound similarly but in all epidermal layers. Immunoelectron microscopy localized the 37-kD protein to the cell periphery in regions between, but never in, desmosomes. By immunofluorescence, the 37-kD protein colocalized with actin as well as with vinculin and uvomorulin in oral tissues. Like the 37-kD protein, vinculin and uvomorulin were absent from the basal layer. Based on its appearance, localization, and solubility properties, the 37-kD protein is probably a component of adherens junctions; its restriction to suprabasal cells and exclusion from the epidermis are unique.

Actins↗
PubMed1992

Cytoplasmic domain of the 180-kD bullous pemphigoid antigen, a hemidesmosomal component: molecular and cell biologic characterization.

Using a serum sample of a bullous pemphigoid (BP) patient we have isolated a cDNA clone encoding a portion of a 180-kD polypeptide component of the hemidesmosome, the "BP180 autoantigen." The identity of the clone was confirmed by the generation of a fusion protein antibody that recognizes BP180 in both a basal epithelial cell extract of bovine tongue and extracts of human epidermal cells. Immunoelectron microscopy indicates that the 588-bp cDNA encodes a cytoplasmic fragment of BP180. Furthermore, the wide species reactivity of the fusion protein suggests that this portion of BP180 is highly conserved. In cultured human epidermal cells processed for confocal immunofluorescence microscopy, the fusion protein antibody generates a punctate cell substrate-associated staining pattern that is similar to that seen using BP230 antibodies. Using the original BP180 cDNA we have now isolated additional cDNA clones encoding approximately 1800bp of BP180 the 3' sequence of which overlaps with the sequence detailed in Guidice et al (J Clin Invest 87:734-738, 1991). Secondary structural analyses have been undertaken on the predicted amino acids encoded by the 1800bp. These suggest that the collagen-like sequences of BP180 described by Guidice et al (ibid.) are separated by a putative transmembrane region from the domain of BP180 recognized by our fusion protein antibody. Indeed, BP180 appears to belong to a relatively rare group of proteins in which the N-terminus is located in the cytoplasm and the C-terminus is extracellular. We detail some preliminary biochemical experiments in support of this hypothesis. We discuss possible functions of BP180 and BP230 in the hemidesmosome.

Amino Acid Sequence↗
PubMed1992

Stroke and Parkinson's disease.

BACKGROUND AND PURPOSE: We sought to determine whether the recently reported decreased incidence of stroke and atherosclerotic disease in a university hospital-based Parkinson's disease patient population would be demonstrated in our patient population. METHODS: We performed a retrospective case-control review of the last 119 Parkinson's disease patients discharged from the Middleton Veterans Affairs Hospital Neurology Service to study the incidence of ischemic stroke, myocardial ischemia, tobacco use, and other stroke risk factors. Controls were age and sex matched and were randomly taken from 238 non-Parkinson's disease discharges in which stroke or myocardial infarction was not the reason for hospitalization. RESULTS: The cumulative incidences of ischemic stroke, hypertension, and diabetes mellitus were not significantly different between groups. Myocardial infarction, coronary artery disease, tobacco use, atrial fibrillation, cancer, and ethanol abuse were significantly more prevalent in the controls, whereas dementia and congestive heart failure were the only variables studied that were more prevalent in the Parkinson's disease patients. CONCLUSIONS: Our study failed to demonstrate that Parkinson's disease patients from a Veteran population were protected from ischemic stroke.

Aged↗
PubMed1992

Suicidal ideation and suicide attempts among patients with panic disorder: a survey of two outpatient clinics.

OBJECTIVE: Recent epidemiologic studies found that 20% of subjects with the diagnosis of panic disorder had attempted suicide. This study sought to determine the prevalence of suicidal ideation and suicide attempts among patients with panic disorder and whether the presence of comorbid borderline personality disorder influenced the prevalence of suicidal thoughts and behavior. METHOD: At two outpatient clinics, experienced clinicians conducted retrospective reviews of data from the intake interviews and charts of 59 patients with panic disorder and comorbid borderline personality disorder and 234 patients with panic disorder with or without axis II disorders other than borderline personality disorder. RESULTS: Suicide attempts were reported by 2% of the patients with panic disorder, compared to 25% of the patients with both panic disorder and borderline personality disorder. In addition, 2% of the patients with panic disorder, compared to 27% of the patients with panic disorder and borderline personality disorder, reported suicidal ideation that was judged to be of clinical significance. CONCLUSIONS: The rate of suicidal ideation and suicide attempts for psychiatric outpatients with panic disorder was discrepant with the findings of the earlier studies. The increased suicide risk in this group of patients was associated with borderline personality disorder, increased substance abuse, and affective instability. While 61% of the panic disorder patients and 78% of the patients with both panic disorder and borderline personality disorder reported thinking about death, this must be distinguished from actual suicidal ideation and clinical risk of suicide.

Adult↗
PubMed1992

Hemidesmosomes in the epithelial cell line 804G: their fate during wound closure, mitosis and drug induced reorganization of the cytoskeleton.

Recently, we identified a novel epithelial cell line, 804G, derived from rat bladder, which readily forms hemidesmosomes in vitro. One of the major structural components of the plaques of 804G cell hemidesmosomes is a 230 kDa antigen recognized by autoantibodies in the sera of patients with bullous pemphigoid (BP). An additional polypeptide of 180 kDa also localizes to the hemidesmosome plaque of 804G cells as determined by immunoelectron microscopy. Using confocal fluorescence/phase microscopy, we have employed both 230 kDa and 180 kDa antibody probes to monitor the fate of hemidesmosomes following closure of in vitro wounds, during mitosis, and following drug induced disruption of the cytoskeleton. The punctate cell-substratum associated staining generated by the hemidesmosomal antibodies in stationary unwounded 804G cell cultures is greatly diminished or even lost in cells which enter wound sites, presumably in response to enhanced cell motility. Few, if any hemidesmosomes are observed at the ultrastructural level in cells which have migrated into the wound area. However, as closure of the wound becomes complete, staining along the substratum attached surface of cells returns. During mitosis, there is no obvious loss of hemidesmosomal antigens along the basal surface of 804G cells, and formed hemidesmosomes can be observed in mitotic cells at the ultrastructural level. In 804G cells treated with colchicine, the typical subnuclear pattern of distribution of hemidesmosomal antigens is unaffected. In contrast, following treatment of 804G cells with cytochalasin D, hemidesmosomal antigens become concentrated at the cell periphery and no longer appear in the subnuclear region. Furthermore, formed hemidesmosomes are observed at the cell periphery of cytochalasin D-treated cells by electron microscopy. We suggest that hemidesmosomal plaques are mobile within the plasma membrane. We speculate that hemidesmosomal interactions with extracellular ligands are dynamic and we discuss a possible mechanism by which cytochalasin D induces reorganization of hemidesmosomes along the basal surface of 804G cells.

Actin Cytoskeleton↗
PubMed1992

Use of latex agglutination testing in diagnosing pediatric meningitis.

BACKGROUND: Latex agglutination (LA) tests are ordered frequently on cerebral spinal fluid (CSF) specimens obtained from pediatric patients to identify pathogenic bacteria as early as possible in an acute infection. METHODS: Six hundred ten LA tests were performed on 176 patients suspected of having meningitis. RESULTS: Five patients with meningitis had positive LA tests. We found that the CSF white blood cell (WBC) count, and differential were the best predictors of meningitis. CONCLUSIONS: By limiting the use of LA tests to those patients having CSF with abnormal WBC counts or with positive Gram stains, the number of tests ordered would have been reduced. This practice would greatly reduce laboratory expense.

Adolescent↗
PubMed1992

Adhesion complex formation after small keratectomy wounds in the cornea.

The adhesion complex of the corneal epithelium consists of the hemidesmosome and its associated structures, such as anchoring filaments, lamina densa of the basement membrane, and anchoring fibrils. It contributes to the adhesion of the corneal epithelium to Bowman's layer. To understand the adhesion complex better, an electron microscopic and immunofluorescence analysis was done of the reformation of the adhesion complex in small (1 mm) keratectomy wounds in the guinea pig cornea. In these wounds, the epithelium, hemidesmosomes, basal lamina, anchoring fibrils, and anterior stroma were removed. The wound bed was epithelialized completely by 24 hr after wounding. Immunofluorescence analyses involved the use of antibodies against plaque components of the hemidesmosome, an antibody against laminin, and an antibody against the collagen VII component of anchoring fibrils. At 18 hr after wounding, there was no morphologic evidence of hemidesmosomes at the epithelial-stromal interface. At 24 hr, hemidesmosomes were observed, with or without subjacent lamina densa. Furthermore, plaque components were detected by immunofluorescence in those cells in contact with the wound bed. In contrast, no type VII collagen was detected. On day 7, collagen VII, laminin, and bullous pemphigoid autoantibody markers colocalized along the wound bed as determined by immunofluorescence. However, at the ultrastructural level, even though the lamina densa of the basal lamina was observed primarily where hemidesmosomes were present, it remained incomplete. In this study, the precise temporal sequence in which components are incorporated into the assembling adhesion complex was described during wound healing. Furthermore, the possibility that the hemidesmosomal plaque nucleates the formation of the underlying basal lamina was discussed.

Animals↗
PubMed1991

Gene-specific formation and repair of cisplatin intrastrand adducts and interstrand cross-links in Chinese hamster ovary cells.

We have used three methods to study the formation and repair of intrastrand adducts and interstrand cross-links in the DNA of Chinese hamster ovary cells induced by the anticancer drug cis-diamminedichloroplatinum II (cisplatin). Using atomic absorption spectroscopy, we found that 21% of the total genomic cisplatin adducts were removed at 8 h and 42% at 24 h. We used ABC excinuclease digestion, coupled with out previously reported methodology to quantify DNA in specific genomic regions. These adducts were removed faster in the transcribed dihydrofolate reductase and c-myc genes compared to a noncoding fragment, a region containing the little or nontranscribed c-fos oncogene, and to the overall genome. Interstrand cross-links in specific sequences were quantified by Southern hybridization of denatured-renatured DNA separated on a neutral gel. We found that cross-links were removed more efficiently from the gene regions than intrastrand adducts and, at high levels of cross-linking, removal was similar from transcribed and from nontranscribed regions.

Animals↗
PubMed1991

A novel hemidesmosomal plaque component: tissue distribution and incorporation into assembling hemidesmosomes in an in vitro model.

The hemidesmosome and its associated structures, such as anchoring fibrils, form a complex structure, the polypeptide composition of which has only recently begun to be elucidated. We describe the characterization of a monoclonal antibody, mAb6A5, directed against a 200-kDa polypeptide found in the cytoplasmic-most area of the hemidesmosomal plaque. This 200-kDa polypeptide is immunologically distinct from the 180- and 230-kDa hemidesmosomal plaque components recognized by bullous pemphigoid (BP) autoantibodies. mAb6A5 recognizes hemidesmosomes of stratified squamous epithelia in a number of species, including human tissue. mAb6A5 also recognizes pseudo-stratified epithelium, but not simple or transitional epithelia. During de novo hemidesmosome assembly in an in vitro model of epithelial wound healing, the 200-kDa polypeptide is in most instances deposited at the epithelial-stromal interface after plaque components recognized by BP autoantibodies, but before the collagen type VII component of anchoring fibrils. We discuss possible mechanisms of hemidesmosomal plaque assembly.

Animals↗
PubMed1991

Effect of specific enzyme inhibitors on replication, total genome DNA repair and on gene-specific DNA repair after UV irradiation in CHO cells.

We have studied the effect of some specific enzyme inhibitors on DNA repair and replication after UV damage in Chinese hamster ovary cells. The DNA repair was studied at the level of the average, overall genome and also in the active dihydrofolate reductase gene. Replication was measured in the overall genome. We tested inhibitors of DNA polymerase alpha and delta (aphidicolin), of poly(ADPr) polymerase (3-aminobenzamide), of ribonucleotide reductase (hydroxyurea), of topoisomerase I (camptothecin), and of topoisomerase II (merbarone, VP-16). In addition, we tested the effect of the potential topoisomerase I activator, beta-lapachone. All of these compounds inhibited genome replication and all topoisomerase inhibitors affected the overall genome repair; beta-lapachone stimulated it. None of these compounds had any effect on the gene-specific repair.

Animals↗