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J J Thompson

Publications and source records attributed to J J Thompson.

At least 37 records · Page 2Linked to original sources
PubMed1987

Gradient acrylamide/agarose gels for electrophoretic separation of intact human very low density lipoproteins, intermediate density lipoproteins, lipoprotein a, and low density lipoproteins.

An exponential gradient gel with 0-10% acrylamide and 0.5% agarose was developed for electrophoresis of intact high molecular weight lipoproteins. This system resolves very low density lipoproteins, intermediate density lipoproteins, lipoprotein a, and low density lipoproteins in a size-dependent fashion. The characteristic relative mobility of these species can be determined in relation to protein and colloidal gold reference materials. Electron microscopy of selected lipoprotein fractions confirmed that relative mobility was related to apparent lipoprotein diameter. The composite gel medium can be used with prestained lipoproteins and permits immunoelectroblotting for qualitative analysis of apolipoprotein constituents.

Electrochemistry↗
PubMed1986

Lipoprotein lipase-suppressing mediator in serum of endotoxin-treated rats.

The conditions under which lipoprotein lipase-suppressing mediator is present in serum of endotoxin-treated rats was determined in this study. The suppression of lipoprotein lipase activity in 3T3-L1 cells was used as a bioassay for mediator in serum. Endotoxin (0.1-10 micrograms/ml) and serum from control rats did not suppress lipoprotein lipase activity. Maximum suppression of cell lipoprotein lipase activity (70%) by serum from endotoxic rats required a cell exposure time of 5 h. At the highest dose of endotoxin used (1 mg/100 g), significant suppression was achieved when cells were incubated with 0.5% serum from endotoxic rats (P less than 0.05). Serum obtained 2-3 h after endotoxin injection possessed the maximal ability to suppress lipase activity, but suppressing activity was not present in serum collected 8 h after endotoxin. Rats rendered tolerant to endotoxin by 5 daily injections (0.1 mg/100 g) did not contain detectable levels of mediator in serum after endotoxin injection. The results demonstrate that the presence of lipoprotein lipase activity-suppressing mediator is transitory after in vivo exposure of naive rats to endotoxin, but does not appear in serum of endotoxin tolerant rats.

Animals↗
PubMed1986

Juvenile periodontitis. I. Demonstration of local immunoglobulin synthesis.

The purpose of this investigation was to determine the presence and quantity of immunoglobulin G (IgG) and albumin (ALB) in specified periodontal tissues and serum from patients diagnosed as having juvenile periodontitis (JP), using an immunoelectrophoresis technique and to determine which portion of the lesion generated the greatest local immunoglobulin production. Serum and tissue samples were obtained from 19 patients (ages 13-21 years) who were diagnosed as having JP; 18 were female; 16 were black. Normal, diseased, and granulomatous gingival/periodontal tissues were collected during full thickness flap surgery, then minced, homogenized, and centrifuged. Supernatants containing the gingival/periodontal protein and the serum were electrophoresed against rabbit antihuman IgG and ALB. The relative IgG/ALB ratios in each specimen were plotted against known concentrations of IgG using a least squares analysis to provide evidence for local synthesis. In comparing mean IgG/ALB ratios for all tissue types, it was noted that normal gingiva did not differ significantly from serum. Diseased and granulomatous tissues, taken together or separately, had significantly higher IgG/ALB ratios than normal gingiva or serum, demonstrating that 73.6% of the IgG present was due to local synthesis. However, the greatest amounts of locally produced IgG were found in the granulomatous tissue from the deepest areas of the defects.

Adolescent↗
PubMed1985

Production and characterization of a monoclonal antibody to dog hepatic lipase.

Partially purified dog hepatic lipase was used as antigen to produce monoclonal antibodies in mice. In addition to enzyme-linked immunosorbent assay (ELISA), a reliable and efficient procedure for screening antibodies reacting to hepatic lipase has been developed. A method to distinguish antibodies directing to active site or non-active site epitopes has also been described. We obtained three positive clones that survived after subcloning and expansion. All three monoclonal antibodies possess gamma one (gamma 1) heavy chains and kappa (kappa) light chains. Specificity of monoclonal antibody LDHL No. 537 to dog hepatic lipase was demonstrated by passing post-heparin plasma through its immunoaffinity column. Only dog hepatic lipase was removed by LDHL No. 537 from post-heparin plasma. The immunoaffinity chromatography also demonstrated the co-existence of three enzyme activities (mono- and triacylglycerol lipase and phospholipase A1) on the dog hepatic lipase molecule. The subunit weight of dog hepatic lipase has been estimated at 57500 +/- 600 (n=3) by using immunoaffinity chromatography and the combination of immunoprecipitation and autoradiography methods.

Animals↗
PubMed1985

Identification of a mouse monoclonal antibody, LHLP-1, specific for human Lp(a).

Heretofore, immunologic reagents used to define and quantify human Lp(a) have been polyclonal in origin and therefore heterogeneous in antigenic specificity. We report here the isolation of a mouse monoclonal antibody, LHLP-1, monospecific for Lp(a). The antigen reactive with LHLP-1 was expressed in both lipoprotein Lp(a) as well as apolipoprotein Lp(a) delipidated by SDS treatment; however, disulfide reduction of apolipoprotein Lp(a) inhibited LHLP-1 reactivity. The antigen reactive with LHLP-1 on Lp(a), therefore, appears not to require lipid for expression of its conformationally dependent (disulfide-inhibitable) epitope. Antigen reactivity was virtually absent in the apoB and other proteins contained in very low density, low density, and high density lipoprotein particles. Immunologic quantification of Lp(a) in individual serum samples with a rabbit reference antiserum or LHLP-1 showed good correlation. We conclude that the monoclonal antibody LHLP-1 identifies an antigen unique to Lp(a) and that this antibody may therefore be useful in the further characterization and measurement of human Lp(a).

Animals↗
PubMed1984

Adenocarcinoma of the esophagus: relationship to Barrett mucosa.

Primary adenocarcinoma of the esophagus is thought to be a rare lesion. However, pathologic records at our institution from 1979 to 1982 show that adenocarcinoma accounted for 17 of 89 (19%) of all primary malignant tumors in the esophagus. All 17 cases arose in Barrett mucosa. In eight cases, there was surgically proved involvement of the gastric cardia or fundus. In six of these cases, there was evidence of esophageal dysplasia and/or carcinoma in situ adjacent to or remote from the proximal margin of the tumor. The pathologic findings therefore strongly suggest an esophageal origin of these lesions with subsequent spread into the stomach. Clinical and radiographic findings at presentation were indistinguishable from those of squamous cell carcinoma. However, 10 patients had long-standing reflux symptoms, and Barrett esophagus had presumably been present for some time prior to the development of malignancy. Since adenocarcinoma evolves through a sequence of dysplasia and carcinoma in situ in pre-existing Barrett epithelium, the best hope for improving survival may be periodic endoscopic surveillance of asymptomatic individuals who have this condition.

Adenocarcinoma↗
PubMed1984

Local immunoglobulin synthesis in juvenile periodontitis: initial findings.

An electro-immunoassay technique was used to determine simultaneously immunoglobulin G (IgG) and albumin concentrations in serum and extracts of gingival tissue comprising the pocket wall. Assays of samples obtained from seven patients with juvenile periodontitis (mean age, 18 years) indicated that local synthesis accounted for 72% of the IgG found in the gingiva.

Adolescent↗
PubMed1983

Ileocecal endometriosis presenting with abdominal pain and gastrointestinal bleeding.

A 26-year-old woman with enteric endometriosis presenting with cecocolic intussusception, a cecal mass on barium enema, and gastrointestinal hemorrhage is described. Laparotomy revealed cecocolic intussusception, ileocecal endometrial implants, and cecal mucosal ulceration presumed secondary to ischemia of the intussuscepted bowel. Histopathology showed serosal and subserosal endometrial implants without mucosal invasion. A review of the literature of endometrial bowel disease is presented.

Abdomen↗
PubMed1983

Barrett's metaplasia and adenocarcinoma of the esophagus and gastroesophageal junction.

Most previous studies of Barrett's metaplasia have used biopsy material to document cell, gland, and architectural types, leading to inaccurate or incomplete conclusions. The present study presents data from eight esophagogastrectomy specimens of Barrett's metaplasia with associated neoplasia, which were evaluated topologically by use of dissecting microscopy, specimen radiography, scanning electron microscopy, and routine histologic examination. Barrett's metaplasia was found to be mosaic of cell, gland, and architectural types, showing variable degrees of atrophy and maturation toward intestinal and gastric epithelium. Zonation was not found. Surface mucous, goblet, absorptive, mucous neck, mucous gland, and neuroendocrine cells were found in all cases; Paneth, chief, and parietal cells were found in approximately half. The presence of villar architecture with lining goblet and absorptive cells is unique and can be used to make a biopsy diagnosis. In one case, only a minute residual focus of Barrett's metaplasia was found, suggesting that the pathogenesis of some cases of adenocarcinoma of the lower esophagus and gastric cardia unassociated with Barrett's metaplasia may be the same. Nine cases of adenocarcinoma of the gastroesophageal junction unassociated with Barrett's metaplasia, studied during the same time period, had similar epidemiologic characteristics including mean age, age range, and sex distribution. Multifocal dysplasia and carcinoma in situ were found in all but one case. In two of eight cases adenomatous change was present; one of these resembled a villous adenoma of the colon with malignant degeneration. Barrett's metaplasia thus appears to be important as a precursor of adenocarcinoma in the region of the lower esophagus and gastroesophageal junction. The significance of these findings in relation to previous reports is discussed.

Adenocarcinoma↗
PubMed1983

Barrett esophagus: reticular pattern of the mucosa.

Barrett esophagus is an acquired condition with progressive columnar metaplasia of the esophagus due to chronic reflux esophagitis. The premalignant nature of this entity is well recognized. However, radiologic diagnosis has been limited by the nonspecificity of findings associated with the condition. We recently reviewed 29 cases of pathologically proved Barrett esophagus. Radiologic examinations revealed hiatal hernias, gastroesophageal reflux, esophagitis, and strictures. None of these findings are diagnostic of Barrett esophagus. In seven cases, however, double-contrast radiography also revealed a delicate reticular pattern in the esophagus. In all but one case, there was an adjacent stricture, and this reticular appearance extended distally a short but variable distance from the stricture. To our knowledge, this unusual reticular pattern has not been described previously, and it represents a valuable radiologic sign of Barrett esophagus. The etiology of this finding is uncertain, but correlation with the gross surgical specimen in one case suggests that it results specifically from areas of "villous" metaplasia in Barrett epithelium. This delicate reticular pattern appears to be a specific radiologic criterion for the diagnosis of Barrett esophagus.

Adult↗
PubMed1983

Carcinoma of the gastric cardia in young people.

Carcinoma of the gastric cardia is usually considered a disease of middle-aged or elderly patients and is rarely suspected in young individuals. However, six cases are reported in patients under 45 years of age. The youngest was 26. A review of patient records revealed no obvious predisposing factor to account for the development of cancer at an early age. In four cases, double-contrast upper gastrointestinal examinations revealed a polypoid mass at the cardia. In two cases, however, the true origin of a tumor arising at the cardia was only recognized by obliteration of the normal anatomic landmarks at the cardia associated with irregular areas of ulceration. In all six cases, the tumor extended into the distal esophagus. Five patients presented with dysphagia. Careful radiographic evaluation of the cardia and fundus is therefore essential to rule out an underlying carcinoma of the cardia in all patients with dysphagia, regardless of age.

Adenocarcinoma↗
PubMed1983

Adenocarcinoma of the esophagus in patients with scleroderma.

Three cases of patients with esophageal involvement by scleroderma, chronic reflux esophagitis, and adenocarcinoma of the distal esophagus are presented. An underlying columnar metaplasia (Barrett esophagus) was identified in two patients and postulated in the third. It is believed that scleroderma patients with symptomatic chronic gastroesophageal reflux should be investigated for Barrett epithelium. If it is present, these patients should be followed and considered as having an increased risk for development of adenocarcinoma of the esophagus.

Adenocarcinoma↗
PubMed1982

Case report 210.

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Adult↗
PubMed1982

Expression of DR antigens in freshly frozen human tumors.

DR antigens are thought to function as differentiation antigens and to restrict immune recognition between T cells and B cells, monocyte/macrophages, Langerhan's cells, and endothelial cells. These antigens are commonly found on tissue culture lines from metastatic melanomas and tumors of lymphocyte derivation but are notably uncommon on cell lines from other malignancies. Using frozen tissue sections, a monoclonal antibody (WI 691-13-17) known to detect an epitope common to all DR alloantigens on the beta (light) chain of DR antigens, and a two-step indirect immunoperoxidase technique, DR antigens were found on all metastatic lesions tested and on many primary tumors and their histogenetic precursors. The technique of using monoclonal antibodies in indirect immunoperoxidase staining of freshly frozen tissue allows individual cells to be assessed for antigen expression and presumably more accurately reflects in vivo antigen expression than results obtained from cells selected by tissue culture methods.

Antibodies, Monoclonal↗
PubMed1982

Evidence for local immunoglobulin synthesis in periodontitis.

Periodontitis lesions are characterized by an increased plasma cell infiltrate. These cells have been shown to increase in number with the severity of the disease and in vitro synthesis of immunoglobulins by gingival plasma cells has been shown in tissue culture. This study correlated gingival and serum immunoglobulin levels to reflect the in vivo production of immunoglobulin. An electroimmunoassay technique was employed to determine serum and gingival IgG concentrations simultaneously relative to reference albumin levels in 16 patients with periodontitis. Results indicated that local immunoglobulin synthesis and accumulation occurs at the gingival site. Data obtained demonstrated that an average of 74.56% of the IgG found in gingiva from periodontitis patients was of local origin.

Albumins↗
PubMed1982

Double-contrast enema in pelvic endometriosis.

The radiographic findings on barium enema in 42 patients with endometriosis were reviewed and correlated with those at surgical and laparoscopic examination. Radiographic abnormalities were detected in 27 patients. In nine patients, purely extrinsic mass effect was identified; bowel wall involvement in these patients was not present at laparoscopy. In 16 of 18 patients subsequently shown to have bowel wall involvement, mass effect with fine mucosal crenulation was identified. Annular or polypoid involvement was also noted. Mass effect with crenulation, although not entirely specific, appears to be a characteristic finding in patients with bowel wall involvement due to endometriosis.

Adolescent↗