Search PubMed⌕ Search

Biomedical subjects

W Tittor

Publications and source records attributed to W Tittor.

At least 37 records · Page 2Linked to original sources
PubMed1982

[New aspects of the pathogenesis of primary biliary cirrhosis, a study of 42 patients (author's transl)].

Studies on 42 patients (38 women, 4 men) with chronic-destructive non-purulent cholangitis or primary biliary cirrhosis demonstrated that the duration of symptoms does not correlate with the histological stages. The shortest duration of symptoms was found in patients in the cirrhotic stage. Enzyme levels measured at the time of diagnosis indicated that--contrary to serum bilirubin and serum copper levels--they did not correlate with the stage of the disease. There was an increased frequency of allergic signs in the past history of this group of patients. Furthermore, in all the women (average age 45) there was a 29% abortion rate. Among the three control groups (no liver disease, chronic-aggressive hepatitis, other forms of liver disease), the one with chronic-aggressive hepatitis also showed a high abortion rate (19.5%).

Abortion, Spontaneous↗
PubMed1982

Validity of monoamine oxidase in serum for diagnosis of liver cirrhosis: estimation of predictive values, sensitivities and specificities.

The validity of monoamine oxidase (EC 1.4.3.4) activity in serum for the diagnosis of fibroproliferative liver disorders was assessed by measuring the specificity, sensitivity and positive and negative predictive values of the enzyme. Enzyme activity was measured in sera of 567 patients including those with biochemically and/or histologically verified non-fibrotic liver diseases (n = 64), liver fibrosis (n = 45), and liver cirrhosis (n = 51). The fraction of liver cirrhotic subjects with pathologically elevated monoamine oxidase activity (greater than 630 U/1) was 0.61, whereas only 0.16 of the cases with liver fibrosis and 0.11 of those with non-fibrotic liver diseases had abnormally high enzyme activities. Among the various categories of diseases tested, significantly increased enzyme activities were confined to liver cirrhosis and chronic active hepatitis. For liver cirrhosis, sensitivities and specificities were calculated as functions of various cut-off (critical) values of monoamine oxidase activity in serum, and with respect to a reference population of healthy men and non-cirrhotic subjects. The predictive value of the positive test result (enzyme activity higher than 720 U/1) at a prevalence of liver cirrhosis of maximum 0.033 (estimated incidence of chronic liver diseases in West Germany) is 0.68 if tested against healthy persons and less than 0.30 if tested against patients with non-liver cirrhotic diseases. It is concluded that monoamine oxidase is probably not helpful in the early diagnosis of fibroproliferative liver dysfunctions but may provide a parameter of complications of cirrhosis, e.g. portal-systemic collateral circulation (portal hypertension).

Chronic Disease↗
PubMed1980

[Age-dependent immunological parameters].

Lymphocyte stimulation, frequency of autoantibodies and concentration of immunoglobuline classes were investigated in 90 persons of 3 age-groups (5--15, 30--40 and 65--95 years of age). An age dependent decrease of MLC- and PhA-reactivity was observed. In contrast, the frequency of autoantibodies and the concentration of IgA increased with age. Individuals with a positive antinuclear factor demonstrated decreased IgA levels. No correlation between lymphocyte stimulation and autoantibody-frequency could be observed.

Adolescent↗
PubMed1980

[Immune response and B hepatitis (author's transl)].

The different forms of chronic hepatitis are due to different individual immune responses after infection with hepatitis B virus. A report is given about specific and unspecific defense mechanisms coming into play after infection, about immunological and immunopathological reactions, and about the pathogenetic significance of these processes. At present unfortunately our knowledge in this particular field is rather limited; more detailed information is needed about humoral, cellular, immune complex related, and autoimmunological events, if one wishes to explain the different courses of hepatitis on these grounds.

Antibody Formation↗
PubMed1978

Presensitization of potential kidney recipients detected by cell kinetic studies in the pooled mixed lymphocyte reaction.

An accelerated response in the pooled mixed lymphocyte reaction (PMLR) and/or the existence of cytotoxic antibodies indicates presensitization of potential kidney recipients. The absence of cytotoxic antibodies does not exclude presensitization, which can be demonstrated by a premature response in the PMLR. However, transfusions may also lead to impaired proliferation. In some patients, blood transfusions induce blocking activities. The possible mechanisms of this phenomenon are discussed. Measuring the immune response by cell kinetic studies with the PMLR gives further information on the immune state of potential kidney recipients.

Cytotoxicity, Immunologic↗
PubMed1977

[T-cell subpopulations in mixed lymphocyte cultured. Model of T-cell interactions].

The present studies have shown that two subpopulations of thymus-dependent lymphocytes may act synergisticaly in the mixed lymphocyte reaction (MLR) in the mouse. One subpopulation was well represented in the young adult thymus and the other in lymph nodes. For optimum synergy, both populations must be allogeneic to the stimulator cells. Pretreatment of either population with mitomycin-C abolished synergy. In a cinetic study lymph node cells were proliferating before thymus cells. A mixture of thymus and lymph node cells (4:1) demonstrated a proliferation pattern like pure lymph node cells. Possibly, in MLC 3 cell types react, a T1- and T2-cell triggered by LD-antigens and a T-effector cell triggered by SD-antigens. These different T-cell subpopulations may interact in MLC.

Animals↗
PubMed1976

[Lymphocyte stimulation of healthy probands with a "Hodgkin's HL-A type" (author's transl)].

Reported correlations between HL-A type and Hodgkin's disease suggest that genetic factors as HL-A associated immune response genes may play a role in the pathogenesis of Hodgkin's disease. Assuming that healthy individuals having a Hodgkin HL-A constellation may demonstrate impaired immune function mitogen stimulation and mixed lymphocyte reaction were carried out. However, lymphocytes of 12 persons with a Hodgkin-HL-A type did not show any abnormality in the in vitro tests when compared to a control group.

Antigen-Antibody Reactions↗
PubMed1975

[Acute leukemia in the terminal phase of Hodgkin's disease: a consequence of the depressed immune function?].

A 52 year old patient suffering from Hodgkin's disease received ionizing radiation and chemotherapy. 7 years after the diagnosis was made he died of acute leukemia. In the recent past similar cases were reported in the literature. There it was suggested that the leukemogenic effect of treatment may be an etiological factor for the development of leukemia. The clinical and experimental data show that the immune function of thymus-dependent lymphocytes is depressed in patients with Hodgkin's disease. According to the Burnet's immune surveillance theory the T-lymphocytes eliminate malignant cells in an early stage. If this T-dependent immune function is depressed - as in Hodgkin's disease - further malignancies may develop.

Acute Disease↗
PubMed1974

Synergy among responding lymphoid cells in the one-way mixed lymphocyte reaction. Interaction between two types of thymus-dependent cells.

The present studies have shown that two subpopulations of thymus-dependent lymphocytes may act synergistically in the mixed lymphocyte reaction (MLR) in the mouse. One subpopulation was well represented in the young adult thymus and the other in lymph nodes. For optimum synergy, both populations must be allogeneic to the stimulator cells. Pretreatment of either population with mitomycin-C abolished synergy. Anti-theta serum abolished both MLR responding and synergizing activities of lymphoid cells. The two thymus-dependent subpopulations were both present in the spleen, and displayed different migratory patterns when injected into irradiated mice: one population went to spleens of the irradiated mice, the other to lymph nodes. The effects of anti-thymocyte serum on the MLR and upon synergy were assessed. While minor differences exist and are herein described, our overall results strongly suggest that in our experiments with synergy in MLR, we may be dealing with the same T(1)- and T(2)-cell subpopulations described by Cantor and Asofsky and coworkers (1, 2, 4, 5, 14) as displaying synergy in the graft-vs.-host reaction.

Animals↗