Neuropsychiatric symptoms in active construction painters with chronic solvent exposure

A cross-sectional study was performed to assess whether chronic solvent exposure of painters is associated with increased neuropsychologic symptoms. 401 painters and 209 construction workers without solvent exposure, both groups with at least 10 years of employment, were subjected to extensive clinical examinations. Standardized questionnaires were used for medical and occupational history. Painters reported an excess of specific symptoms that could be assigned to mood and behaviour. The differences between specific and unspecific questionnaire outcomes as well as the positive correlation between chronic exposure index and symptom scores support the hypothesis of solvent induced effects. These symptoms are related to life-long solvent exposure rather than current exposure levels. At present the questions of time course and reversibility or irreversibility of symptoms cannot be answered. The predictive value of these symptoms for subsequent neuropsychiatric morbidity remains to be elucidated in a future follow-up study.

Association of the TNFa13 microsatellite with systemic sclerosis in Japanese patients

OBJECTIVES

To elucidate the contribution of microsatellite polymorphisms of TNFa and TNFb alleles to the pathogenesis of systemic sclerosis (SSc) by comparing the allele distribution among populations with different HLA susceptibility genes in SSc.

METHODS

TNFa and TNFb microsatellite polymorphisms were determined by PCR in 54 Japanese and 50 German SSc patients and in normal controls. HLA-DR genotyping was carried out by PCR-SSCP.

RESULTS

The frequency of TNFa13 was significantly increased in Japanese SSc (p=0. 011, OR=8.53, 95% confidence intervals (95%CI)=2.46, 32.51, and p<1. 0 x 10E-5, OR=10.35, 95%CI=4.88, 22.09) and SSc with antitopoisomerase I antibody (a-Scl-70) (p=0.021, OR=33.25, 95%CI=3. 39, 800.76, and p<1.0 x 10E-5, OR=24.42, 95%CI=8.40, 72.83), compared with the German patient group and German controls, respectively. This increase was not only attributable to a higher prevalence of TNFa13 in Japanese compared with Germans (p=0.005, OR=3.55, 95%CI=1.60, 7.85) but was also caused by an increase in SSc, especially in the a-Scl-70 positive patients (p=0.028, OR=6.88, 95%CI=1.16, 22.60) compared with Japanese controls. TNFa13 was positively in linkage disequilibrium with HLA-DRB1*1502 (LD=0.053, t=2.69). Association analysis indicated that both TNFa13 and DRB1*1502 might have comparable probabilities of being susceptibility factors for SSc with a-Scl-70 in Japanese. Prevalences of TNFa6 and 13 were significantly increased and prevalences of TNFa2, and 7 were significantly decreased in Japanese controls as compared with German controls.

CONCLUSION

TNFa13 is a genetic marker for SSc with a-Scl-70 in Japanese patients. Various differences in the prevalences of TNFa alleles between Japanese and German controls were established.

A multidisciplinary cross-sectional study on solvent-related health effects in painters compared with construction workers

OBJECTIVES

The main aim of the study was to examine possible solvent-associated effects on the nervous system in currently employed painters. Special attention was paid to evaluate subtle health effects.

MATERIALS AND METHODS

A total of 401 painters and 209 construction workers without solvent exposure with at least 10 years of professional experience were subjected to a clinical, neurological, psychiatric, neuropsychological and neurophysiological examination. For personal medical and occupational history, standardized questionnaires were used. A quantitative rating of exposure was obtained by expert rating of the respective occupational history without knowledge of the individual test results.

RESULTS

There was no excess of somatic disorders or solvent-associated adverse effects on the nervous system. No distinct effects of solvent exposure on nerve conduction velocities (NCV) or cognition were found. Discrete NCV deficits in painters were not considered a sign of subclinical polyneuropathy. Painters, however, reported an excess of specific symptoms that could be assigned to "mood and behaviour". The differences between specific and non-specific questionnaire outcomes on the one hand and the positive correlation between chronic exposure index and symptom scores on the other hand support the hypothesis of solvent-induced effects. Because data is lacking on past solvent exposure, it is not possible to relate these effects to current exposure limits.

CONCLUSIONS

Currently employed painters differ from controls not exposed to solvents with respect to the frequency of certain symptoms in mood and behaviour. These symptoms are related to life-long solvent exposure rather than to current exposure. At present, the issue of time course and reversibility or irreversibility of these symptoms cannot be answered. The predictive value for subsequent neuropsychiatric morbidity remains to be elucidated in follow-up studies.

Th2 cells as effectors in postirradiation pulmonary damage preceding fibrosis in the rat

PURPOSE

Radiation-induced pneumonitis and subsequent pulmonary fibrosis are important dose-limiting complications of radiotherapy. Their pathogenesis is known only in part. T-lymphocytes comprise a significant part of the infiltrating cells but little is known about their role. The aim of this study was to define the function of T-lymphocytes during development of postirradiation pneumonitis and pulmonary fibrosis.

MATERIALS AND METHODS

Rats received a unilateral lung irradiation of 20 Gy. Kinetics of T-lymphocytes isolated from irradiated and non-irradiated lungs were analysed. Subsequent CD4 depletion experiments were performed to affirm the importance of CD4+ T-cells in the development of lung fibrosis. Finally, the T helper-cell subtype of the T-lymphocytes was analysed by determining the cytokine mRNA by RT-PCR.

RESULTS

A selective increase of CD4+ T-cells was observed peaking 4 weeks after irradiation in the irradiated lungs. When rats were depleted of these cells, the postirradiation thickening of parenchyma was significantly reduced as determined by morphometric analysis of lung tissue sections. In addition, it was found that IL-4 mRNA was selectively increased in the CD4+ T-cells isolated from irradiated lungs, which indicates a lymphocyte reactivity dominated by Th2 cells.

CONCLUSION

The results suggest a critical role for Th2 CD4+ T-lymphocytes in the pathogenesis of radiation-induced pneumonitis preceding lung fibrosis.

TNFa and b microsatellites in Germany

Allele frequencies of TNFa and TNFb microsatellites were determined from 315 healthy unrelated Germans (mothers and putative fathers) by means of PCR. They were stably inherited and segregated in a Mendelian way. New mutations were not observed.

Different distribution of HLA class II and tumor necrosis factor alleles (TNF-308.2, TNFa2 microsatellite) in anti-topoisomerase I responders among scleroderma patients with and without exposure to quartz/metal dust

OBJECTIVE

To investigate the influence of quartz/ metal dust exposure on the pathogenesis of systemic sclerosis (SSc; scleroderma), by an immunogenetic comparison of HLA class II and tumor necrosis factor (TNF) alleles in patients with and without exposure.

METHODS

A retrospective study of 30 SSc patients exposed to quartz/metal dust (qSSc) and 50 patients with idiopathic SSc (iSSc) was conducted by DNA-based typing of HLA, TNF-308, and TNFa/b microsatellite alleles.

RESULTS

A neutral or protective haplotype in iSSc anti-topoisomerase I (anti-topo I) responders was found to be a susceptibility haplotype in qSSc patients. HLA-DRB1*0301 (DR3), a component of the extended haplotype HLA-DQA1*0501;B1*0201;DRB1*0301; TNF-308.2;TNFa2/b3, had a decreased frequency in iSSc anti-topo I responders compared with non-responders (P = 0.03, odds ratio [OR] 0.11, 95% confidence interval [95% CI] 0.00-0.95), but a significantly increased frequency in qSSc anti-topo I responders compared with controls and with iSSc anti-topo I responders (P = 0.00004, Pcorr = 0.006, OR 11.38, 95% CI 3.17-44.35 and P = 0.0002, Pcorr = 0.02, OR 30.0, 95% CI 2.05-986, respectively). In contrast, DRB1*1104 (DR5) and DRB1*11/15 (DR5/DR2) with no TNF-308.2 and TNFa2 alleles were prevalent in only the iSSc anti-topo I responders compared with controls (P = 0.0005, Pcorr = 0.04, OR 11.0; 95% CI 2.68-45.93 and P = 0.0002, Pcorr = 0.02, OR 12.43, 95% CI 3.65-40.04, respectively).

CONCLUSION

The mechanisms that lead to the development of anti-topo I in qSSc and iSSc patients are suggested to be distinct, although it is not clear that the two diseases themselves are different.

The pathogenic 16/6 idiotype in patients with silica associated systemic lupus erythematosus (SLE) and uranium miners with increased risk for development of SLE

OBJECTIVE

To investigate the prevalence of the 16/6 idiotype (16/6 Id), a major cross reactive idiotype of anti-DNA antibodies involved in the pathogenesis of experimental lupus, in subjects with an exogenous risk for the development of systemic lupus erythematosus (SLE).

METHODS

The titer of 16/6 Id was determined by ELISA in sera of uranium miners exposed to heavy quartz dust: 15 developed definite and 12 probable SLE, 34 had clinical symptoms, and 27 had only serological signs (medium to high titer anti-dsDNA antibodies) of possible connective tissue disease (CTD) development.

RESULTS

The prevalence of 16/6 Id was higher in all groups compared to healthy blood donors. It was 18.5% in miners with SLE (definite and probable) and 22.2-26.5% in miners with clinical and/or serological signs for developing CTD. All 16/6 Id positive miners were positive for anti-dsDNA antibodies and other autoantibodies associated with CTD. The prevalence of 16/6 Id in anti-dsDNA positive miners correlated slightly with CTD/SLE symptoms: 55.6% in patients with SLE, 47.4% in miners with possible CTD/SLE, and 22.2% in miners without CTD symptoms. Further, at short term followup, disease progressed in 2 miners of the 16/6 Id positive, but not in 16/6 Id negative miners.

CONCLUSION

The detection of 16/6 Id in miners exposed to quartz dust may indicate a higher risk for development of SLE, warranting further studies of the role of 16/6 Id in the development of SLE in a cohort with the same sex, ethnicity, geographic region, and occupation.

Local production of interleukin-4 during radiation-induced pneumonitis and pulmonary fibrosis in rats: macrophages as a prominent source of interleukin-4

Fibrosis of lung tissue is a frequent and serious consequence of radiotherapy of mammary carcinoma. The pathogenesis of radiation-induced pulmonary fibrosis remains unclear. Cytokines such as transforming growth factor beta (TGFbeta) and interleukin-4 (IL-4) have been reported to stimulate collagen synthesis in fibroblasts in vitro. The aim of this study was to document the presence of IL-4 during the development of post-irradiation lung fibrosis. Right lungs of male Fischer rats were irradiated with a single dose of 20 Gy and IL-4 expression in the irradiated lungs was monitored for a period of three months. IL-4 gene transcription as determined by ribonuclease protection assay (RPA) as well as IL-4 synthesis as shown by Western blotting increased in the irradiated lungs reaching a plateau concentration within 3 weeks after irradiation. Enhanced IL-4 production was still detected at day 84 after irradiation. The cellular origin of IL-4 was analyzed by in situ hybridization and two-color immunofluorescence on lung tissue sections and on cytospin preparations of leukocytes obtained from bronchoalveolar lavages. These experiments revealed a substantial IL-4 production by macrophages during development of post-irradiation lung fibrosis.

Monitoring of flaps by measurement of intracapillary haemoglobin oxygenation with EMPHO II: experimental and clinical study

OBJECTIVE

To find out whether measurements of intracapillary haemoglobin oxygenation made with the non-invasive Erlangen microlightguide spectrophotometer (EMPHO II) provided accurate data about the oxygen supply as well as the blood flow to free flaps in rats and humans.

DESIGN

Experimental, and prospective open clinical study.

SETTING

University hospital, Germany. ANIMALS and

SUBJECTS

Thirty male Wistar rats and 20 patients who underwent microsurgical transplant of free flaps (radial forearm, n = 8; osteocutaneous fibula, n = 7; and myocutaneous from the lateral thigh, n = 5).

INTERVENTIONS

Measurement of the haemoglobin oxygenation of the skin before, during, and after transfer of the flap.

MAIN OUTCOME MEASURES

Reproducibility and mean curves for haemoglobin oxygenation and haemoglobin concentration.

RESULTS

All values were reproducible, and there were only slight fluctuations. Uninjured skin in rats (baseline value) oxygenation of the total haemoglobin concentration ranged from 15% to 45% (mean 23%). After the flaps were raised there was a slight increase (to a mean of 37%), probably as a result of reactive hyperaemia. There was a rapid decrease within a few minutes of arterial occlusion, and residual oxygenation of up to 20% after perfusion stopped. The flap was totally deoxygenated after 1 h. Venous occlusion caused a similar pattern and all flaps were deoxygenated by 30 min. In the clinical study ligation of the vascular pedicle caused a massive reduction in values but after anastomosis there was significantly higher haemoglobin oxygenation (P = 0.05) and this continued to increase postoperatively. There were no complications and oxygenation gradually and continuously decreased from the base of the flap to the periphery.

CONCLUSION

The non-invasive EMPHO II provides reliable and easily assessable data about the circulation and supply of oxygen to a transplanted free flap.

Molecular analysis of HLA-DPB1 alleles in idiopathic systemic sclerosis patients and uranium miners with systemic sclerosis

According to clinical mainifestation and autoantibody pattern [anti-Scl-70, anti-centromere antibodies (ACAs)], systemic sclerosis is a connective tissue disease with heterogenous subgroups. PCR-sequence-specific-oligonucleotide typing was used to study the genetic association of HLA-DPB1 alleles in 54 patients with idiopathic systemic sclerosis, 26 uranium miners with systemic sclerosis and 70 unrelated healthy control subjects. Systemic sclerosis patients with and without former employment in mines were divided into two subgroups according to their scleroderma-typical autoantibody specificities--anti-Scl-70 positive and ACA positive--and third subgroup comprising the rest. Statistical analysis revealed a significantly increased frequency of DPB1*1301(p=0.0001, corrected p=0.011) in idiopathic anti-Scl-70-positive systemic sclerosis cases when compared with unexposed controls. In the same group, we observed an enhanced frequency of DPB1*0601 and *1701 alleles. Since these three alleles carry the information for a glutamic acid residue in position 69 of DPB1, we tested the association of this residue with anti-Scl-70 expression. A strong association between anti-Scl-70 positivity in idiopathic systemic sclerosis patients and amino acid residue 69 of DPB1 was observed when compared with anti-Scl-70-negative idiopathic systemic sclerosis patients (p=0.0009) or unrelated controls (p=0.0007). ACA expression was not associated with the presence of any DPB1 allele tested. The data show that anti-Scl-70 expression in idiopathic systemic sclerosis patients is linked with DPB1*1301 whereas anti-Scl-70-positive miners do not show such a DPB1 association. Futhermore, the data indicate that glutamate 69 of DPB1 might be involved in the susceptibility to idiopathic anti-Scl-70 expression.

Systemic lupus erythematosus after heavy exposure to quartz dust in uranium mines: clinical and serological characteristics

Epidemiological, clinical and serological data of uranium miners with symptoms of connective tissue diseases (CTD) were collected during the control examinations for occupational lung diseases since 1975. Twenty eight definite (four or more ARA criteria) and 15 probable (2-3 ARA criteria) SLE were diagnosed. The estimated prevalence among heavily silica exposed uranium miners was up to 93 in 100,000. The only significant differences to nonexposed SLE patients were decreased frequency of arthritis and photosensitivity and the absence of anti-Sm and anti-U1-RNP antibodies. ANA were found in all definite SLE patients examined with the following specificities: anti-dsDNA (in 44.4%), & anti-Ro/SSA (in 55.6%, four cases together with anti-dsDNA) and anti-La/SSB (in 22.2%). The autoantibody profiles of patients with probable SLE were similar, but with a lower frequency of ANA, anti-dsDNA and anti-Ro/SSA. Middle to high-titred autoantibodies to dsDNA, Ro/SSA and La/SSB were detected in 3.2% uranium miners with no (N = 1229) and in 20.6% with some symptoms (one ARA criterion and/or two or more of other CTD typical symptoms, N = 68) of CTD development. We conclude, that the strong exposure to dust with a high content of silica may predispose to or initiate the development of SLE. The detection of SLE-typical antibodies in quartz dust-exposed miners may indicate a higher risk for the development of systemic autoimmune disease.

Anti-CENP-B response in sera of uranium miners exposed to quartz dust and patients with possible development of systemic sclerosis (scleroderma)

OBJECTIVE

To look for anti-CENP-B antibodies and their diagnostic relevance in patients negative and positive for anticentromere antibodies (ACA) with different risk for the development of systemic sclerosis (SSc), including uranium miners exposed to quartz dust.

METHODS

We studied sera of 107 patients with SSc, 121 patients with possible SSc, 202 uranium miners heavily exposed to quartz dust, 14 patients with vibration induced white fingers, and 240 control patients. Subjects were screened for ACA by indirect immunofluorescence on HEp-2 cells (IIF-ACA) and then for anti-CENP-B autoantibodies by an ELISA using eukaryotically expressed human full length recombinant CENP-B protein.

RESULTS

All IIF-ACA positive sera of "idiopathic" SSc (N = 19), "idiopathic possible" SSc (N = 6) and other patients (N = 11), and 17 of 19 IIF-ACA positive sera of miners exposed to silica with (N = 13) and without (N = 6) symptoms of SSc reacted with CENP-B in this assay. Of the 622 IIF-ACA negative sera, 28 were found positive for anti-CENP-B. There was a significant increase of the prevalence of anti-CENP-B antibodies in IIF-ACA negative patients with possible SSc (11 of 109) and in miners exposed to silica (11 of 196) compared to a group of men older than 60 years with diseases or symptoms not related to SSc (1 of 138).

CONCLUSION

(1) CENP-B is also the major target of the IIF-ACA response in diseases other than scleroderma and in the risk group of miners exposed to quartz dust. (2) Anti-CENP-B antibodies can be found in IIF-ACA-negative sera, particularly in those at risk for SSc. (3) The detection of anti-CENP-B antibodies in miners exposed to quartz dust may indicate a high risk group for developing SSc and reveals possibilities for the study of early pathogenetic changes as well as exogenic and endogenic factors involved in the development of this disease.

Measurements of tissue blood flow by the hydrogen clearance technique (HCT): a comparative study including laser Doppler flowmetry (LDF) and the Erlangen micro-lightguide spectrophotometer (EMPHO)

The purpose of this study was to compare the hydrogen clearance technique (HCT) with two different, well-established techniques, i.e., the laser Doppler flowmetry (LDF) and the Erlangen micro-lightguide spectrophotometer (EMPHO), for tissue blood flow measurements in an experimental setting. For the animal experiments, we chose a rat model for arterial and venous flap thrombosis, using the epigastric groin flap. Forty male dark Aguty rats were included in the study. The animals were divided into eight groups, each with a different vascular thrombotic model. HCT was used to collect 1,467 measurements, and 2,934 graphs were recorded; 27 measurements (54 graphs) had to be discarded due to faulty electrode placements and electronic noise. In 19 of the 27 discarded measurements the cause of failure was moving of the awaking animal with disruption of the decay signal. The LDF and EMPHO measurements were performed continuously during each measuring phase. Simple and multiple linear regression and paired t-tests were used to compare the three techniques. The reproducibility of registered blood flow values in phases 1, 3, 6 and 7 varied between 7.8% and 13.6% which is in about the same range as LDF and EMPHO. We could not find a significant difference between the three techniques in this regard. The correlation coefficient for HCT and LDF was r = 0.89. For HCT and EMPHO we found r = 0.67. Sensitivity and specificity values for HCT were both 1.0 in detecting arterial and venous flap thrombosis; for LDF we found values of 0.89 and 0.92, respectively. Sensitivity and specificity values for EMPHO were 0.92 and 0.95, respectively. After careful evaluation of three different techniques (HCT, LDF, and EMPHO) for measurements of local tissue blood flow we came to the conclusion that HCT must be favoured as a reliable tool for quantitative measurement of local tissue blood flow and early diagnosis of arterial and venous flap thrombosis.

Amino acid sequence of the region of beta 2-glycoprotein 1 (gp1) which mediates binding of autoantibodies to the cardiolipin-gp1 complex in humans

Anticardiolipin antibodies (ACA) in sera from patients with autoimmune and infectious diseases were tested for binding to beta 2-glycoprotein 1 (gp1) in order to determine whether human gp1 acts as a cofactor for the binding of ACA to cardiolipin (CL) or as an antigen recognized by ACA. While none of the ACA-positive sera tested recognized gp1 by itself, gp1 was necessary for the binding of ACA to CL in sera from four patients with autoimmune diseases. In three of the four sera the presence of lupus anticoagulant (LA) was detected by prolonged partial thromboplastin time (PTT). Examinations using the bovine equivalent of human gp1 contained in fetal calf serum (FCS) and adult bovine serum (ABS) showed that the human protein can be replaced by the bovine equivalent in the enzyme-linked immunosorbent assay (ELISA). Using affinity-purified antibodies directed against the CL-gp1 complex it was shown that the binding of these antibodies is dependent on the concentration of the bovine gp1 equivalent contained in the formed complex. Similar results found with the human gp1 confirmed this assertion. In order to find out which region of gp1 might mediate the binding between ACA and cardiolipin, we examined to what extent selected oligopeptide sequences of gp1 can substitute for the protein. Peptide P2 (representing the amino acids at positions 268-278 of the gp1 molecule) and gp1 showed about the same binding capacity. Histidine in this peptide seems to be essential for the binding to CL as we found decreased binding with peptides modified in this position. Conclusions from this work show that gp1 does not act as a relevant antigen for ACA, but occupies an essential function in the complex formed with cardiolipin for a certain group of ACA.

[Antinuclear antibodies as early diagnostic criteria of developing collagen disease in quartz dust exposure--a case report]

One and a half years antinuclear autoantibodies (ANA) against Scl-70 and U1-RNP were found in the serum of a quartz dust exposed worker before the clinical manifestation of the progressive systemic sclerosis (PSS). Only a discrete lung fibrosis and an enlargement of the heart was seen at the time of the first autoantibody detection. Because workers with an intensive and long-lasting quartz dust exposition take a high risk to develop PSS a sensitive ANA-screening is indicated at minimum suspicion of chronic collagen disease. The detection of a high ANA-titer in a clinical healthy person may give a hint for the possible future development of such a disease and requires the observation of the clinical course and the paraclinical and immunological parameters. A lung fibrosis and/or an enlargement of the heart in X-ray photographs would indicate visceral early manifestations of the PSS before skin symptoms appear.

The Erlangen micro-lightguide spectrophotometer EMPHO I

The Erlangen micro-lightguide spectrophotometer EMPHO 1 was designed for fast diffuse reflection (remission) spectrophotometry in small tissue volumes. The aim was to construct a compact, modular instrument with a high repetition rate which can be adapted to moving organs, e.g. the beating heart in situ, by the use of highly flexible micro-lightguides. Focusing problems, which cannot be solved when conventional optical devices such as microscopes are used in moving tissues, become negligible. A bandpass interference filter disk, which is rotated by a motor serves as a monochromating unit. One diffuse reflection spectrum in a selected wavelength domain is recorded during each revolution of the motor. Special filter disks, with spectral ranges of 400-520, 500-630, 600-1200 nm can be used for different tasks. The monochromated light is transmitted by means of a flexible fluid-lightguide to a photomultiplier tube. The electrical signal, which is proportional to the light intensity is recorded by an IBM-compatible AT. An analogue to digital converter has been developed for the AD conversion. Sampling of the spectra occurs in steps of 2 nm triggered by a decoding unit, containing an EPROM where the function between the wavelength-angular position characteristic of the filter disk is stored. A decoder wheel mounted on the same axle as the driving motor is used to program the decoder unit and to recall the wavelength position function. The decoding procedure enables a high wavelength reproducibility to be attained. The monochromating device allows a sampling velocity of 100 spectra per second. The EMPHO I has been successfully applied to experiments in the beating heart, the brain, the eye, the liver, the small intestine and the skeletal muscle of mammals. First investigations have also been performed in the heart during open heart surgery and in human skin. The apparatus has a high sampling rate and the small catchment volume allows measurements of remission spectra in tissue volumes supplied by only a few capillaries. The absolute oxygenation and the relative haemoglobin concentration can be determined by on-line computer evaluation of the recorded spectra and displayed on a screen.

Measurements of angular distributions of Rayleigh and Mie scattering events in biological models

Remission spectroscopy in living tissues can only be performed because scattering processes induce a pronounced amount of backscattered light. New types of scattering chambers were constructed in order to investigate the angular distribution of light intensities caused by scattering events typical for living tissues. Different solutions and suspensions containing microspheres, haemoglobin molecules, erythrocytes and liver homogenate were used in order to gain basic information applicable to remission spectrophotometry in tissue. Reflection spectroscopy in biological tissues is only possible because of the scattering properties of the material under observation. Light which penetrates the sample is remitted from the tissue. The remission is caused by the scattering of the light by different biological structures and particles. This scattered light gives information about the optical properties of the particles and structures in an integral form. A scattering chamber for small sample volumes has been developed for measurements of the optical properties of various particles in suspension. Measurements of scattering diagrams from microspheres with an average diameter of 7 microns, artificial particles, haemoglobin solutions, mixtures of microspheres and haemoglobin as well as erythrocytes and mitochondria have been performed. The different optical behaviour of the measured signals is qualitatively discussed.

[Pharmacokinetics and cardiac effect of beta-acetyldigoxin and digitoxin in combination therapy with nifedipine]

The effect of nifedipine (N) on the pharmacokinetics and pharmacodynamics of beta-acetyldigoxin (AD; n = 11) and digitoxin (DGT; n = 10) was studied in 21 patients with cardiac insufficiency stage II-III NYHA. Glycoside plasma concentration and renal excretion as well as electrocardiogram heart rate, atrioventricular transconduction time (PQ), duration of electrical systole corrected for heart rate (QTc), mean amplitude of T waves in leads V2 to V6 (TV2-6) and systolic time intervals total electromechanical systole index (QS21), left ventricular ejection time index (LVETI), pre-ejection period index (PEPI), PEP/LVET-ratio were recorded repeatedly before and during co-administrations of 40-60 mg/day N. Plasma AD concentrations were 0.64 +/- 0.22 ng/ml (mean +/- SD) before and 0.61 +/- 0.21 ng/ml during co-administration of N over 10-14 days, plasma DGT concentrations 13.9 +/- 4.1 ng/ml before and 13.7 +/- 4.5 ng/ml during co-administration of N over 4-6 weeks. Daily glycoside excretion was not affected by treatment with N. Heart rate and PQ-interval were not significantly changed during co-administration of N whereas T-wave flattening was intensified and QT-duration was lengthened. Concomitant treatment of AD and N led to an increase of PEPI and PEP/LVET compared to AD alone in ten patients whereas the systolic time intervals after concomitant treatment of DGT and N in most patients did not differ from those after DGT alone. From our findings we conclude that N had no clinically significant effect on pharmacokinetics and pharmacodynamics of AD or DGT.

[Serologic determination of non-A, non-B hepatitis]

As to the antigens of hepatitis non-A non-B there are controversial opinions concerning existence and demonstrability. Up to now they were not successful neither in standardizing nor in unifying their test systems. On the basis of own investigations of 1,600 sera of patients with hepatitis non-A non-B and of several control groups, no doubt, a high incidence of precipitations among the sera of hepatitis non-A non-B could be established, but we did not succeed in standardizing the material which was uniform also with regard to the causing virus. Since real antigen-antibody reactions are causative for the heterogeneous phenomena, there nature is to establish by means of suitable methods (methods of the 3rd generation, monoclonal antibodies).

[Immunohistologic findings in the liver, spleen, brain and skeletal muscles in fatal cholestatic viral hepatitis (following double infection with hepatitis B and non-A/non-B?)]

We report immunohistological findings in liver, spleen, brain, and skeletal muscle of a 23-year-old woman with hepatitis nonA/nonB caused by contaminated anti-D-globulin. She died in a liver coma. At autopsy, a chronic liver dystrophy with cirrhosis was diagnosed. The necrotic areas of the liver showed a collapse of the reticulin framework, newly formed collagen fibres, and diffuse inflammation with immunohistological evidence of IgG, CIq, C9, and fibrinogen. C4 and C9 could be localised in bile thrombi and in the cytoplasm of pseudotubular transformed hepatocytes. In addition, C9 was found in blood vessel walls. A local distribution of HBsAg was found in the cytoplasm and/or the periphery of liver cells. HBcAg could not be detected in any of 5 different regions of the liver. A serum with antibodies to acute phase antigen of nonA/nonB hepatitis stained the cytoplasm and nuclei of (mostly intact) liver cells focally and their cell membranes diffusely. Patchy deposits of IgA and IgM were demonstrated in liver, brain und spleen. Circulating antibodies to cell nuclei and smooth muscle reacted with the patient's own liver and brain but not with spleen and skeletal muscle.--It is suggested that the manifold immunohistological findings in this patient are an expression of the vain attempt of the organism to clear away antigenic material, probably induced by different hepatitis viruses.

[Demonstration of hepatitis A virus in the feces]

On the basis of own examinations methodology and results of the demonstration of the virus A in the stools and of the proof of antibodies in the serum are described. The parameters of the virus-A-hepatitis which are important for practice are further the basis for diagnosis, therapy and surrounding prophylaxis in routine work. They were compiled in a table.