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Biomedical subjects

W F Doe

Publications and source records attributed to W F Doe.

At least 91 records · Page 5Linked to original sources
PubMed1978

Macrophage stimulation by bacterial lipopolysaccharides. II. Evidence for differentiation signals delivered by lipid A and by a protein rich fraction of lipopolysaccharides.

Stimulation of macrophages to lyse tumor cells is a property common to lipopolysaccharide (LPS) extracted from a variety of smooth and rough bacterial strains by several different preparative procedures. The relationship between macrophage stimulation and the structural characteristics of LPS is defined. In protein-free LPS, lipid A bears the stimulatory signal which results in the differentiation of elicited macrophages into killer cells. The polysaccharide moiety is neither stimulatory itself nor does it block the activity of complete LPS on macrophages. Extraction of LPS by the butanol or Boivin procedures produces preparations in which LPS is complexed through its lipid A moiety to a protein rich component, LAP. Isolated LAP delivers a macrophage differentiation signal which is independent of lipid A. The presence of these two structurally distinct constituents in the cell walls of gram-negative bacteria broadens the biological environments in which they can stimulate macrophages in vivo.

Cell Differentiation↗
PubMed1977

Functional characterization of a stable, noncytolytic stage of macrophage activation in tumors.

The state in which macrophages (Mphi) from regressing Moloney sarcomas could kill tumor target cells was a highly labile one which decayed rapidly in vitro. Thereafter, regressor Mphi were noncytolytic. Mphi from several different progressing sarcomas failed to kill, even when challenged with target cells immediately after explantation. Similarly, thioglycollate-induced peritoneal Mphi (TG-Mphi) did not kill. Noncytolygic Mphi derived either from progressing sarcomas or from long-term (up to 96 h) cultures of regressor Mphi were exquisitely sensitive to stimulation by bacterial lipopolysaccharide (LPS); picogram/milliliter amounts induced killing. Similar concentrations of LPS had no demonstrable effect on TG-Mphi. Thus, tumor Mphi generally appeared to have been primed in vivo, with those in regressing sarcomas having additionally acquired cytolytic activity. Inability of progressor Mphi to kill apparently stemmed from lack of, or failure to respond to, the signal needed in vivo to trigger cytolytic activity, rather than the total absence of activation.

Cytotoxicity, Immunologic↗
PubMed1976

Inflammatory cells in solid murine neoplasms. I. Tumor disaggregation and identification of constituent inflammatory cells.

Mechanical and enzymatic methods of disaggregating tumors were studied with the goals of (1) minimizing cell losses while (2) maintaining functional and surface membrane markers needed to objectively identify inflammatory cells (IC)1 in resultant suspensions. Application of the principles and methods described makes accurate estimation of the percentage of each IC type present in neoplasms possible for the first time. Compared to purely mechanical means of disaggregating tumors, all enzyme mixtures tested markedly increased yields of viable cells/g neoplasm. Best results were obtained with a combination of collagenase and a protease of broader substrate range (alpha chymotrypsin, papain, pronase or trypsin). The combination of enzymes that gave the highest yields with the least effect on inflammatory cell markers was trypsin, collagenase and DNAse (TCD). Because mechanical injury appeared to be the greatest single cause of cell loss (the enzymes themselves had little direct effect), potential sources were identified and either eliminated or minimized. With TCD, depending on the tumor system, cell recovery (measured as DNA recovered in cell suspensions) was as high as 50% and yields were as much as 6.9 X 10(8) viable cells/g tumor. Complete disaggregation was not required to obtain representative IC populations from tumor fragments. Neutrophils, eosinophils and mast cells from disaggregated neoplasms were counted in Giemsa stained cytocentrifuge preparations based on their unique morphologic appearances. Macrophages were identified by their capacity to phagocytose zymosan, a function which proved highly resistant to the effect of enzymes. Flourescent microscopic identification of brain associated thymus antigen (BATA) allowed quantification of T lymphocytes, since this marker was virtually unchanged by enzyme exposure. Surface immunoglobulin (Ig) was stripped from B lymphocytes most rapidly by pronase and chymotrypsin, slowly by trypsin and papain, and not at all by collagenase. Ig positive cells therefore could be quantified in suspensions generated by collagenase or very short (20 min) exposure of fragments to trypsin.

Animals↗
PubMed1976

IgA deficiency in one of identical twins.

A disease resembling childhood coeliac disease occurred in one of identical twins. When the twins were investigated at the age of 23 the initial diagnosis could not be substantiated but the twin who had been ill had selective IgA deficiency. Differences dating from early infancy may have been a result of the discordance for IgA deficiency. Thus in some patients environmental influences may be important in either the initiation or the perpetuation of the deficiency.

Adolescent↗
PubMed1976

Biochemical and morphological studies on human jejunal mucosa maintained in culture.

1. The combination of a wire-mesh support with the roller-tube technique is described as a procedure for the culture of human jejunal mucosa in vitro. 2. The technique has been applied to fragments (approximately 10 mg) of jejunal biopsies from both normal subjects and patients with coeliac disease. 3. The cultured tissue has been shown by radio-autography to incorporate [3H]leucine into proteins of the villus epithelial cells and [3H]thymidine into nucleic acid, predominantly by the enteroblasts. 4. Although the tissue protein DNA contents fall during culture, it was found that the combined tissue and medium DNA content remained constant during culture and may be used as a reference for enzyme and biochemical studies on cultured intestinal biopsies.

Cells, Cultured↗
PubMed1976

Radiological and histological findings in six patients with alpha-chain disease.

Detailed radiological and histological features of alpha-chain disease are presented against a background of the clinical and biochemical findings. The separation of this syndrome from other varieties of "Mediterranean" lymphoma is emphasized. The radiologist should in some instances be able to suggest the diagnosis in his differential diagnosis of abnormalities seen on examination of the small bowel. The histopathologist should be able to provide a diagnosis from examination of a peroral jejunal biopsy. One patient with this relatively uncommon disease had evidence of a hypertrophic osteoarthropathy. Two of the six patients had a transient episode of acute abdominal distension which resolved on conservative management.

Adolescent↗
PubMed1975

Mediation systems in bacterial lipopolysaccharide-induced hypotension and disseminated intravascular coagulation. I. The role of complement.

We have studied the role of complement in lipopolysaccharide (LPS)-induced hypotension and disseminated intravascular coagulation (DIC) by comparing the effects of injection of three preparations of LPS from E. Coli 0111:B4, S. minnesota Re595, and S. marcescens. Injections of nonlethal doses of these LPS preparations into normal rabbits produced decreases in mean arterial blood pressure during a 5-h period. When rabbits treated with cobra venom factor (CoF) to deplete C3 were injected with the various LPS preparations, mean arterial pressures fell at a rate and extent essentially identical to that observed in normal rabbits. Rabbits genetically deficient in C6 also demonstrated LPS-induced hypotensive changes. Only minimal, or no changes in plasma C3 levels or serum CH50 values were detected in normal rabbits after LPS injection. Hypotensive changes were also induced in rabbits when complement was rapidly activated by intravenous injection of CoF. In contrast to the hypotension induced by LPS, the fall in arterial pressure associated with the consumption of complement was short lived and required the rapid consumption of considerable amounts of C3. The occurrence of DIC noted in normal rabbits injected with each preparation of LPS was not inhibited in either rabbits treated with cobra factor or in C6-deficient rabbits. The DIC was most pronounced after injection of Re595 and S. marcescens LPS. Injection of the various LPS preparations produced a rapid disappearance of circulating neutrophils and mononuclear cells, which occurred with the same kinetics and to the same extent in normal, CoF-treated, and C6-deficient rabbits. Injection of either Re595 LPS or S. marcescens LPS produced a biphasic disappearance of circulating 51Cr-platelets. In contrast, injection of 0111:B4 LPS affected only slightly the rate of disappearance of 51Cr-platelets. Depletion of C3 by cobra factor treatment had no effect on the disappearance of platelets in animals injected with 0111:B4. In marked contrast cobra factor treatment greatly reduced the initial rapid disappearance of platelets in rabbits injected with either Re595 or S. marcescens LPS, but had no effect in the secondary disappearance phase.

Animals↗
PubMed1975

Subepithelial collagen in intestinal malabsorption.

Intestinal biopsies from 146 patients with adult coeliac disease and 13 patients with intestinal villous atrophy of different aetiology were assessed for the presence of subepithelial collagen and compared with a group of 20 control subjects. Subepithelial collagen was a common and non-specific finding observed in intestinal biopsies from patients suffering from adult coeliac disease (36%) and tropical sprue. In adult coeliac disease the described subepithelial changes usually regress following treatment, though marked subepithelial collagen deposition may indicate a poor prognosis. The study showed that the presence of marked subepithelial collagen in a flat jejunal biopsy does not define a separate clinical entity.

Adult↗
PubMed1974

Alpha-chain disease with clinical, immunological, and histological recovery.

Clinical, immunological, and histological recovery in a patient with alpha-chain disease is described. The patient, a 27-year-old Greek man, presented with severe steatorrhoea, abdominal pain, oedema, and hypogammaglobulinaemia. Treatment with tetracycline produced only temporary remission. Intermittent therapy with prednisone and cyclophosphamide together with antibiotics was followed by clinical recovery, return of histological appearances of the small intestine to normal, and disappearance of free alpha-chain protein from the serum. The patient remained well one year later without treatment.

Adult↗
PubMed1974

Intestinal coccidiosis in a patient with alpha-chain disease.

During an ultrastructural study of small-intestinal mucosa from a patient suffering from alpha-chain disease organisms were identified within the epithelial cytoplasm which showed the fine structural features of the coccidian group. Though coccidiosis is well recognized as causing a diarrhoeal and often lethal illness in animals it has been neglected as a cause of disease in man. Thus this finding may be significant and warrants further investigation into its possible role in the pathogenesis of alpha-chain disease.

Adult↗
PubMed1974

Studies on the nature and significance of connective tissue antibodies in adult coeliac disease and Crohn's disease.

Sera from 92 patients with adult coeliac disease, 20 patients with Crohn's disease, and 89 control patients were tested for the presence and immunoglobulin class of anticonnective tissue antibodies. In adult coeliac disease patients taking a normal diet there was a high frequency of sera positive for connective tissue antibodies and the majority were IgA in class. Following gluten withdrawal, IgA class connective tissue antibody activity was strikingly reduced. No such antibody activity was detected in concentrated jejunal fluid collected from 15 patients with adult coeliac disease, seven of whose sera were positive for connective tissue antibody. Connective tissue antibody activity was not absorbed by fractions of gluten. Similarly, preparations of human reticulin and glomerular basement membrane together with elastin and collagen failed to absorb connective tissue antibody.

Absorption↗
PubMed1973

Antireticulin antibody: incidence and diagnostic significance.

Sera from 101 patients with adult coeliac disease, 46 patients with childhood coeliac disease, 50 patients with dermatitis herpetiformis, and 479 patients with various other diseases, including skin, gastrointestinal, haematological, and immunological disorders, have been tested for the presence of the antireticulin antibody. Positive sera were retested at higher dilutions. Antireticulin antibody was only found in a significant proportion of patients with three diseases, ie, coeliac disease, dermatitis herpetiformis, and Crohn's disease. Antireticulin antibody was present in 38 out of 101 patients (38%) with adult coeliac disease, 27 out of 46 patients (59%) with childhood coeliac disease, 11 out of 50 patients (22%) with dermatitis herpetiformis, and nine out of 38 patients (24%) with Crohn's disease. In the 434 other patients with various disorders the antireticulin antibody was present in only six 1.4%) (two patients were pregnant, one had vitiligo, one had tropical sprue, one had reticulum cell sarcoma, and one had pernicious anaemia). In patients with gluten-sensitive enteropathy, ie, coeliac disease and dermatitis herpetiformis, there was a significantly higher incidence in patients taking a normal diet compared with those on a gluten-free diet. The presence of antireticulin antibody would appear to be particularly helpful in diagnosing childhood coeliac disease as it was found in 22 out of 26 patients (85%) taking a normal diet.

Adult↗