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Biomedical subjects

J D Folds

Publications and source records attributed to J D Folds.

At least 55 records · Page 3Linked to original sources
PubMed1983

Rocky Mountain spotted fever vaccine in an animal model.

Formalin-killed, purified Rickettsia rickettsii vaccine was evaluated in a guinea pig model of R. rickettsii infection. Vaccinated guinea pigs were partially protected by the vaccine when challenged with virulent, viable rickettsiae. Greater protection was observed when higher doses of vaccine were given and when frequent booster injections were administered. Stimulation of cell-mediated immunity to the vaccine antigens was variable and also appeared to be achieved more reproducibly with booster vaccinations. Serum antibody was elicited by high doses of vaccine and by booster vaccinations. The presence of serum antibody was useful in predicting immunity to challenge with R. rickettsii.

Animals↗
PubMed1983

The influence of immunoglobulin (IgG) on the assembly of fibrin gels.

The presence of immunoglobulin is shown to alter the network structure of gels formed from purified fibrinogen. Turbidity measurements were used to calculate the effect of increasing concentrations of immunoglobulin on the mass-length ratio of fibrin fibers composing the gels. Normal pooled, human IgG was found to reduce the mass-length ratio of fibrin fibers composing the gel from 7 X 10(12) daltons/cm with no immunoglobulin to 1 X 10(12) in the presence of 40 mg/ml. Monoclonal IgGk was found to be more effective in the reduction of the mass-length ratio than normal IgG. This observation indicates that the immunoglobulin must decrease lateral association of fibrin protofibrils. As the mass-length ratio decreased, the rigidity of the gels increased as the immunoglobulin concentration was elevated (1.2 dynes/cm2 with no immunoglobulin to 2.9 at 15 mg/ml). Since the fibrin fiber diameters were decreased, the number of interfiber crosslinks must have been increased to explain the increase in rigidity. Antifibrinogen, antifibrin intermediate, and antithrombin antibody activity of the immunoglobulins were proved unlikely.

Antibodies, Monoclonal↗
PubMed1982

Simultaneous evaluation for terminal deoxynucleotidyl transferase and myeloperoxidase in leukemia.

A technique for dual staining of cells using terminal deoxynucleotidyl transferase (TdT) and myeloperoxidase (MPO) is described. The technique has been applied to cells of two patients. One patient had chronic myelomonocytic leukemia evolving into acute myelomonocytic leukemia. The other patient had chronic myelogenous leukemia in blast crisis. Our findings indicate that TdT and MPO are exclusive markers except for a rare precursor cell with dual staining in one patient. This study supports the concept of acute mixed leukemia.

Acute Disease↗
PubMed1982

Expression of Treponema pallidum antigens in Escherichia coli K-12.

A colony bank of recombinant plasmids harboring Treponema pallidum DNA inserts has been established in Escherichia coli K-12. By using an in situ immunoassay, we identified four E. coli clones that expressed T. pallidum antigens. Thus, recombinant DNA technology may provide powerful new tools for studying the pathogenesis of T. pallidum infection.

Animals↗
PubMed1982

Immune complexes in experimental T. pallidum infection in rabbits.

The polyethylene glycol precipitation method can be used to detect immune complexes in the sera of rabbits experimentally infected with Treponema pallidum. Immune complexes are present in the serum of rabbits infected either intravenously or intratesticularly and only when syphilitic lesions were present. Immune complexes were not observed in the serum of rabbits infected intradermally with T. pallidum.

Animals↗
PubMed1982

Effect of route of infection with Treponema pallidum. In vitro cellular response to treponemal antigens.

We investigated how route of infection with Treponema pallidum affects cellular responses of various lymphoid tissues. Lymphoid cells from spleens and lymph nodes of rabbits infected intradermally with T pallidum showed enhanced in vitro responses to treponemal antigens when cultured in autologous rabbit serum. Intravenous infection with T pallidum increased the responsiveness of splenic lymphocytes to T pallidum antigen only during the time of lesion development; lymph node lymphocytes responded throughout the first 30 days of infection, whereas peripheral blood lymphocytes did not respond to treponemal antigens in vitro. Lymphocytes from spleens and peripheral blood of intratesticularly infected rabbits poorly to T pallidum when cultured in autologous serum, but not when cultured in normal serum; however, lymph node lymphocytes from the same rabbits responded normally to T pallidum antigen in either type of serum.

Animals↗
PubMed1981

A defect in the formation of uropod-bearing lymphocytes (hand-mirror cells) in patients with the Wiskott-Aldrich syndrome.

The formation of a uropod by lymphocytes (hand-mirror cells) represents a morphologic stage of immune activation and motility in lymphocytes. Immune complexes have been previously shown to induce hand-mirror-cell (HMC) formation in human lymphocytes and have been associated with increased number of HMC in acute leukemia. We studied the ability of immune complexes to induce HMC in patients with Wiskott-Aldrich syndrome (WAS), a disease of cellular immune deficiency. Our findings indicate that lymphocytes from patients with WAS adhere to immune complexes but have a defect in their ability to form HMC when compared with normal human lymphocytes. These results support the concept that immune complexes induce HMC formation and that the HMC is related to the normal cellular immune response.

Antibodies, Viral↗
PubMed1981

Terminal deoxynucleotidyl transferase-positive acute myeloblastic leukemia.

Terminal deoxynucleotidyl transferase (TdT) is a biochemical marker for acute lymphoblastic leukemia (ALL). In studies of ALL at diagnosis, there are usually greater than 40% TdT-positive cells by indirect immunofluorescence, whereas acute myeloblastic leukemia (AML) shows less than 1% TdT-positive cells. Rare cases of TdT-positive AML have been reported. We present here three AML patients with TdT in 15%, 45%, and 90% of the leukemic blasts. The diagnosis of AML was established on the basis of morphology and cytochemistry, and the cases included one patient with Auer rods. Myeloperoxidase was present respectively in 20%, 90%, and 5% of the blasts. There was no Philadelphia chromosome present in the three cases. These results may indicate the simultaneous presence of lymphoid and myeloid populations, or the presence of a blast cell with both lymphoid and myeloid markers.

Bone Marrow↗
PubMed1981

Terminal transferase in acute lymphoblast leukemia in remission.

Terminal deoxynucleotidyl transferase (TdT) is a marker for the diagnosis of acute lymphoblastic leukemia. To determine its value as an indicator of bone marrow remission or impending relapse, serial remission marrows (less than 5% blasts) from 49 patients who had acute lymphoblastic leukemia were examined for TdT by immunofluorescence over the period of a year. Thirty-eight patients (78%) had less than 1% TdT-positive cells. Eleven patients (22%) had slightly elevated levels of TdT (2%-7%) at some time during the study. of these eleven, only two had relapses; however, neither patient had greater than 1% TdT-positive cells within the three months before the relapse. Therefore, it appears that the presence of slightly increased numbers of TdT-positive cells in acute lymphoblastic leukemia remission bone marrows (2%-7%) does not denote impending relapse. In addition, most of the patients with acute lymphoblastic leukemia in remission had less than 1% TdT-positive cells.

Acute Disease↗
PubMed1981

Pre-T chronic lymphocytic leukemia with common acute lymphoblastic leukemia antigen. A new immunologic variant.

Chronic lymphocytic leukemia (CLL) is a B cell disorder but occasionally may have the characteristics of a T cell and rarely as a dual T and B cell. A case of pre- T cell and rarely as a dual T and B cell. A case of pre-T CLL with common acute lymphoblastic leukemia antigens is presented. The markers Studies of the bone marrow lymphocytes were +HTLA, +cALL, +EAC, +Ia, -TdT, -E and peripheral blood lymphocytes were +HTLA, +Ia, -cAll, -EAC, -TdT, -E. The poor course of our patient suggests that more detail subtyping of CLL to identify similar subtype may provide additional prognostic information.

Antigens, Neoplasm↗
PubMed1981

Recurrent bacterial meningitis associated with C8 and IgA deficiency.

A patient with recurrent bacterial meningitis who lacked circulating C8, serum IgA, and secretory IgA is reported. The combined absence of C8 and IgA deficiency has not been previously noted. Although the association of disseminated neisserial infection and absence of the terminal complement components is now well established, the deficiency of bactericidal capability as well as mucosal humoral defense may have been additive in predisposing the patient to recurrent meningitis. The pedigree was uninformative regarding possible linkage of these two uncommon genetic errors.

Adolescent↗
PubMed1981

Formation of nonspecific precipitants in sera by counterimmunoelectrophoresis.

Formation of nonspecific precipitants in sera in different kinds of agarose and batches of barbital buffer by routine counterimmunoelectrophoresis was observed. These nonspecific precipitants consistently locating at the cathodal side of the well upon counterimmunoelectrophoresis can lead to the incorrect interpretation that a specific antibody is present in the patient's serum against the antigens tested. This observation indicates the importance of including a negative control (patient's serum alone) with each individual sample tested by counterimmunoelectrophoresis for the detection of specific antibody to reduce false-positives.

Antibodies, Bacterial↗
PubMed1980

A comparative analysis of human IgM rheumatoid factor degradation by purified elastase and total granule extracts from human polymorphonuclear leukocytes.

A modified digestion system using radiolabeled IgM rheumatoid factors (RF) and unlabeled IgG was used to examine IgM RF digestion by human polymorphonuclear leukocyte (PMN) elastase. Upon molecular sieve chromatography, the radioactive fragments coelute with fragments produced by elastase digestion of an IgM protein giving no RF activity. The fragments represent an Fab2-like fragment, an Fab-like fragment, and small peptides. Utilizing this same system, digests were performed at both acid and neutral pH to compare the proteolytic action of purified elastase on IgM RF (Ove) to the action of the total granule extract (TGE) from human PMN. At pH 4.5, purified elastase exhibits low-level protease activity, producing a slightly degraded IgM fragment with a molecular weight of about 800,000 daltons. In contrast, TGE at pH 4.5 completely degrades IgM RF to small peptides. At pH 7.5, the fragments produced by TGE digestion of IgM (Ove) coelute with fragments produced by elastase digestion under the same conditions. Thus elastase appears to be the major granule protease active in IgM RF degradation at the pH characterizing the inflammatory site.

Female↗
PubMed1980

Laboratory diagnosis of Rocky Mountain spotted fever.

To examine the use of the laboratory in the diagnosis of Rocky Mountain spotted fever and to determine the specificity and sensitivity of the Weil-Felix test, hemagglutination, complement fixation, and skin biopsy immunofluorescence in the hospital, we reviewed our experience during th year 1978. Sera were submitted from 142 patients and skin biopsies from 16 patients suspected of having RMSF. Sensitivity rates of methods in the acute phase were skin biopsy, 70%; Proteus OX-19 agglutination, 65%; hemagglutination, 19%; Proteus OX-2 agglutination, 18%; and CF, 0%. Overall specificity rates were skin biopsy, 100%; hemagglutination, 99%; and agglutination of Proteus OX-2 96% and OX-19 78%. Major problems were failure to submit convalescent serum and nonspecificity of Weil-Felix titer of 1:160. Two cases illustrate the importance of skin biopsy and serologic results. Immunofluorescent examination of skin biopsies for Rickettsia rickettsii is the best procedure currently available for early diagnosis.

Adolescent↗
PubMed1980

Interaction of human polymorphonuclear leukocyte (PMN) elastase with human IgM. Production of a factor enhancing PMN migration in vitro.

Digestion in vitro of human monoclonal IgM by human polymorphonuclear leukocyte (PMN) elastase produces small peptides in addition to larger fragments. These small peptides were shown to enhance PMN locomotion in vitro, as tested by the migration-under-agarose assay. The small peptides from elastase degradation of the Fc5u portion of the IgM molecule also increase PMN migration in vitro. The migration-enhancing factor is stable at 60 degrees C for 20 minutes but is inactivated by boiling for 10 minutes, and has a molecular weight which falls between 1,000 and 10,000 daltons.

Cell Movement↗
PubMed1980

Hansenula polymorpha infection in a child with chronic granulomatous disease.

In a patient with chronic granulomatous disease of childhood documented by the nitroblue tetrazolium test, an infection of the mediastinal lymph nodes developed that was caused by Hansenula polymorpha, an ascomycetous yeast. To our knowledge, this yeast has not been previously shown to be an etiologic agent of disease in man. The diagnosis was made by growing the yeast from cultures of several biopsy specimens collected at the time of thoracotomy. Susceptibility testing showed that the yeast was sensitive to amphotericin B. Treatment with amphotericin B reversed this life-threatening episode.

Amphotericin B↗
PubMed1980

Cell-mediated immunity in Treponema pallidum infected rabbits: in vitro response of splenic and lymph node lymphocytes to mitogens and specific antigens.

Peripheral blood lymphocytes from Treponema pallidum infected rabbits respond poorly to mitogen and specific antigens when cultured in the presence of autologous serum. Reactivity of lymphocytes from the spleen and popliteal lymph nodes of T. pallidum infected rabbits have therefore been examined by lymphocyte transformation using the mitogens phytohaemagglutinin (PHA) and concanavalin A (Con A) and extracts of T. pallidum. Spleen cell populations, both T cell enriched (by nylon wool elution) and non-nylon wool treated, which respond to T. pallidum as early as ten days post infection in normal serum, were suppressed in responses to T. pallidum when cultured in autologous serum. The same lymphocytes responded normally to PHA and Con A. Lymph node cells from infected rabbits responded normally to both T. pallidum antigen and mitogens in either autologous or normal rabbit serum. These data indicate that splenic lymphocytes are sensitive to regulatory factors in autologous serum during the early stages of T. pallidum infection whereas lymph node cells are not.

Animals↗