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Biomedical subjects

F Hardt

Publications and source records attributed to F Hardt.

At least 73 records · Page 4Linked to original sources
PubMed1978

Hepatitis B virus infections among Danish dentists.

Since type B hepatitis is generally regarded as an occupational risk for dentists, the participants at the 1976 annual meeting of the Danish Dental Association were examined for hepatitis B surface antigen (HBsAg) and antibody to HBsAg (anti-HBs). A total of 1,338 dentists (89% of the dentists at the meeting and 29% of all Danish dentists) were included in the study by completion of a questionnaire and by radioimmunoassay of a blood sample for HGsAg and anti-HBs. None of the dentists was HBsAg-positive, but 110 (8.2%) had anti-HBs. An increasing frequency of anti-HBs was found with increasing age, but the figures were similar to the findings in a control population. Evidence is presented that hepatitis found before admittance to or during the time at dental school was predominantly not of type B. In contrast, type B hepatitis predominated during the professional activity of the dentists. On the basis of the serological findings in 29% of all Danish dentists, it is concluded that dentists cannot be regarded as a high-risk group for hepatitis B.

Aging↗
PubMed1978

Humoral and cellular immunity in sarcoidosis.

The Kveim reaction was studied in vivo in 50 patients with sarcoidosis. Commonwealth Serum Laboratories Kveim material and a new Danish Kveim material gave 14 and 8 positive reactions respectively, as well as 6 and 8 equivocal reactions. Forty-six of the patients were also tested in vitro for cell mediated immunity to the Danish Kveim material, using both the leucocyte migration agarose technique and the capillary technique. No significant migration inhibition or stimulation were found. A tuberculin skin test was performed in 49 of the patients, and in 45 a dinitrochlorobenzene sensitivity titer was determined. Both tests revealed a depression of the cell mediated immunity. The serum levels of immunoglobulins IgG, IgA, IgM, IgD, and IgE were determined. The serum of each patient was also examined to determine if organ-non-specific and granulocyte-specific antinuclear factors of IgG class, antibodies against native DNA, rheumatoid factor, mitochondrial antibodies, antibodies against thyroid cytoplasm, and parietal cell antibodies were present. IgG levels were above normal in 28 patients; IgE was above normal in 10 patients, 4 of whom were atopics or had an atopic disposition. Organ-non-specific antinuclear factors were present in 17 patients.

Adult↗
PubMed1977

Liver-cell-membrane autoantibody specific for inflammatory liver diseases.

With an immunofluorescence technique using rabbit hepatocytes isolated by a non-enzymatic method an autoantibody directed against liver-cell-membrance was identified. Sera from 361 patients with various liver diseases and 274 patients with primary non-hepatic diseases-many associated with non-organ-specific auto-antibodies-were examined. The antibody (LMA) was found in 27 out of 72 patients with hepatitis-B-surgace antigen (HBsAg)-negative chronic active hepatitis and in 17 out of 28 patients with HBsAg-negative non-alcoholic cirrhosis. Only two patients had LMA and HBsAg, and both had chronic active hepatitis. One patient with extrhepatic disease was found to have LMA, and this patient had biochemical evidence of liver disease. Hence there is a close correlation between the presence of LMA and HBsAg-negative chronic inflammatory liver diseases and its detection may help in diagnosis.

Adult↗
PubMed1977

Circulating T and B lymphocytes and immunoglobulin containing cells in the liver in chronic active liver disease.

The number of circulating T and B lymphocytes was estimated in 25 patients with biopsy-verified chronic non alcoholic liver disease. Fifteen of these had circulating HBSAg and/or anti-HBSAg and 10 were without these markers of HB virus infection. In both groups of patients a significant decrease of T cells and a parallel significant increase in null cells was found, but any difference with respect to T and null cells in patients in the two groups was not observed. Liver biopsies from five of the patients with and four without HBSAg and/or anti-HBSAg were studied for the presence of immunoglobulin bearing cells. In three out of five liver biopsies from the HBSAg and/or Ab positive patients and in two out of the four liver biopsies from the HBSAg and anti-HBSAg negative patients, a heavy periportal infiltration with plasma cells was found. However, the number and classes of the immunoglobulin containing cells could not be correlated either to the histological evaluation of the stage of activity of the liver disease or to the markers for HB virus infection. The immunological findings in the two groups of patients with chronic liver disease seem to be of the same nature and are most likely a consequence of the liver disease and not the cause of it.

Adult↗
PubMed1977

Humoral and cell-mediated immunity to hepatitis B virus antigen in a haemodialysis-renal transplantation unit.

Hepatitis B surface antigen (HBsAg), the corresponding antibody (anti-HBs), the antibody to hepatitis B core antigen (anti-HBc), and the cellular immune response to purified HBsAg (leucocyte migration inhibition test: LMT-HBsAg) were determined in 19 staff members, 11 long-term haemodialysis patients, and 22 renal transplant patients in a haemodialysis-renal transplantation unit. Past or present infection, as expressed by the presence of circulating anti-HBs or HBsAg, was found in 30 cases (58 per cent) (11 staff members, six dialysis patients and 13 transplant patients). Anti-HBc was found in all the ten HBsAg positive cases--all patients--and in 15 out of 20 anti-HBs positive cases. Four staff members and seven patients had positive LMT-HBsAg; of these only one patient had HBsAg, whereas seven cases had anti-HBs. Neither the antibody determination nor the leucocyte migration inhibition assay disclosed any significant difference between patients and staff which could explain the different course of the hepatitis B virus infection in the two groups.

Antibody Formation↗
PubMed1977

Localisation of e-antigen in nuclei of hepatocytes in HBsAg-positive liver diseases.

By the direct immunofluorescence technique 19 liver biopsies were examined for the presence of the e-antigen associated with the hepatitis B virus infection. With the use of double incubation and blocking experiments with FITC and Rhodamine labelled antisera against hepatitis B core antigen and e-antigen, evidence is presented that the e-antigen is localised in the nuclei of the hepatocytes. We conclude that the e-antigen and the core antigen are not identical, although they are often present simultaneously in the nucleus of the hepatocyte.

Cell Nucleus↗
PubMed1977

Humoral and cell-mediated immunity to hepatitis B virus antigens in acute and chronic liver disease.

The humoral immune response to hepatitis B virus antigens and the cell-mediated immunity to hepatitis B surface antigen (HBsAg) were investigated in 12 healthy persons and 56 patients with various liver diseases. In patients with acute viral hepatitis type B, anti-hepatitis B core antigen was present constantly in serum in all phases, and after clinical recovery simultaneously with anti-HBs. A transitory cellular immune response to HBsAg was demonstrated at the time the antigen was cleared, while a patient with persisting HBs antigenaemia and another with transient hepatitis Bc antigen showed no response during the course of the disease. Cellular immune response to HBsAg was present only infrequently in patients with chronic liver disease type B and non-B, thus suggesting that a cellular immunity to HBsAg is not a prerequisite for the development of these conditions.

Acute Disease↗
PubMed1976

Estimation of lymphocyte subpopulations in the peripheral blood of patients with sarcoidosis.

Lymphocyte subpopulations in the peripheral blood of 36 sarcoidosis patients and 36 age- and sex-matched controls were determined, using the sheep erythrocyte rosette (SRBC-R) technique and immunofluorescence staining with whole rabbit anti-human immunoglobulin antisera. In the patient group the total number of lymphocytes, SRBC-R lymphocytes, and IgM-positive lymphocytes was reduced in comparison to in the control group. In the patient group no correlation could be found between any of the lymphocyte subpopulations and disease stage, cutaneous involvement of the disease, or cutaneous reactivity to purified protein derivative and dinitrochlorobenzene.

Adolescent↗
PubMed1976

Immunological studies in sarcoidosis: a comparison of disease activity and various immunological parameters.

We found it valuable to separate the heterogeneous types of sarcoidosis into more homogeneous groups on the basis of activity and duration of the disease. This view is supported in the present study by the finding of a marked depression of T-cell function in patients with chronic-active sarcoidosis. Patients with acute or chronic-inactive disease had only moderately depressed T-cell function as measured by tuberculin skin test and DNCB index. These results are in agreement with those of some previous investigations. The remainder of the abnormal findings, particularly low total number of circulation T lymphocytes, elevated serum IgG levels, and presence of autoantibodies, could not be correlated to disease activity, extent of the disease, or T-cell function. We have found no explanation for the presence of autoantibodies but suspect that they may be nonspecifically related to the disease process.

Adolescent↗
PubMed1976

Antral gastrin cells. A correlation between the number of gastrin cells and the total concentration of gastrin in serum and in antral mucosa. A pilot investigation.

Correlation between the gastrin cell number of delineated by immunohistological staining and the gastrin content in blood and antral mucosa has been studied in biopsies from the antral region of the human stomach. With a semiquantitative score system of the antral gastrin cells, we found correlation between the number of cells and the gastrin content in mucosa and serum and the grade of atrophic pyloric gastritis in 52 patients with different gastric diseases. It is concluded that further studies will be necessary before it is possible to estimate the total mass of gastrin cells and thereby compare different clinical groups.

Adult↗