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Objective This cross-sectional study determined whether acute sensory irritative or (sub)chronic inflammatory effects of the eyes, nose or respiratory tract are observed in employees who are exposed to naphthalene at the workplace. Methods Thirtynine healthy and non-smoking male employees with either moderate (n = 22) or high (n = 17) exposure to naphthalene were compared to 22 male employees from the same plants with no or only rare exposure to naphthalene. (Sub)clinical endpoint measures included nasal endoscopy, smell sensitivity, self-reported work-related complaints and the intensity of naphthalene odor and irritation. In addition, cellular and soluble mediators in blood, nasal lavage fluid (NALF) and induced sputum (IS) were analysed. All measurements were carried out pre-shift on Monday and post-shift on Thursday. Personal air monitoring revealed naphthalene shift concentrations up to 11.6 mg/m3 with short-term peak concentrations up to 145.8 mg/m3 and 1- and 2-naphthol levels (sum) in post-shift urine up to 10.1 mg/L. Results Acute sensory irritating effects at the eyes and upper airways were reported to occur when directly handling naphthalene (e.g., sieving pure naphthalene). Generally, naphthalene odor was described as intense and unpleasant. Habituation effects or olfactory fatigue were not observed. Endoscopic examination revealed mild inflammatory effects at the nasal mucosa of exposed employees in terms of reddening and swelling and abnormal mucus production. No consistent pattern of cellular and soluble mediators in blood, NALF or IS was observed which would indicate a chronic or acute inflammatory effect of naphthalene in exposed workers. Conclusions The results suggest that exposure to naphthalene induces acute sensory irritative effects in exposed workers. No (sub)chronic inflammatory effects on the nasal epithelium or the respiratory tract could be observed under the study conditions described here.

The aim of this study was to evaluate the effect of exposure to manganese (Mn) on fine motor functions. A total of 48 welders and 30 unexposed workers as controls completed questionnaires, underwent blood examinations, and a motor test battery. The shift exposure of welders to respirable Mn was measured with personal samplers. For all subjects accumulations of Mn in the brain were assessed with T1-weighted magnetic resonance imaging. Welders showed normal motor functions on the Movement Disorder Society-Sponsored Revision of the Unified Parkinson Disease Rating Scale part III. Furthermore welders performed excellent on a steadiness test, showing better results than controls. However, welders were slightly slower than controls in motor tests. There was no association between fine motor test results and the relaxation rates R1 in globus pallidus and substantia nigra as MRI-based biomarkers to quantify Mn deposition in the brain.

Objectives Workplace measurements in the past have shown that the applicable occupational exposure limits (OELs) are regularly exceeded in practice when high-emission welding processes are applied. The InterWeld pilot study was planned as part of an intervention study to show under which conditions compliance with the OEL is achievable in gas metal arc welding (GMAW) with solid wire. The investigation focussed on local exhaust ventilation, i.e. captor hoods and welding torches with integrated fume extraction. Methods Forty tests with hand-guided GMAW were configured by experts with regard to all technical parameters and carried out by a professional welder. Effects of protective measures and process parameters on the exposure to respirable welding fumes and airborne manganese (Mn), chromium, nickel, and hexavalent chromium were investigated. Personal sampling was carried out in the welder’s breathing zone outside the face shield at high flow rates (10 l min−1) in order to achieve sufficient filter loading. Particle masses and welding fume concentrations were determined by weighing the sampling filters. Metal concentrations were analysed by inductive coupled plasma mass spectrometry. In order to evaluate the effects on exposure, the measurements were performed under similar conditions. The data were analysed descriptively and with mixed linear models. For measurements below the limit of detection, the exposure level was estimated using multiple imputation. Results Two to five times higher exposures to respirable welding fumes and airborne metals were observed during welding of 10 mm sheets than during welding of 2- or 3-mm sheets. Welding fume and Mn exposure were reduced by 70 and 90% when on-torch extraction or a captor hood was applied. Other airborne metals were reduced to a similar extent. Modifications on welding parameters led to a reduction of exposure against respirable particles by 51 up to 54%. Conclusions Although proper extraction at the point of origin and lower-emitting process variants ensure a drastic reduction in exposure, compliance with current OELs is not guaranteed. In order to ensure adequate health protection, especially at workplaces where thick sheets with long relative arc times are processed, there is a need for technical development.

Hazardous substances in welding and allied processes are the inhalable/respirable substances generated, which are absorbed by the human body (Fig. 1.1). At a certain concentration, these substances may cause a risk to health.

To determine the health and safety program required to protect welder workers, an evaluation of workplace hazards which complies with national, regional or international health and safety regulations (e.g. labour protection law), shall be completed.

Any predominant hazardous substance is called a key component (for a specific combination of process and material). A main component of the welding fume is a component of occupational medical importance, the percentage of which in the welding fume is not predominant, i.e., this component is no key component of the welding fume. Main components shall not be equated with key components.

Despite considerable technical and organisational efforts, full protection from the effects of hazardous substances cannot be attained under today’s operating conditions. Therefore, it is necessary and beyond dispute that, for some operations, necessary technical prevention should be accompanied by preventive occupational medical care. The purpose is avoidance and early detection especially of chronic diseases.

In order to minimise the health hazard to the welder by hazardous substances at the workplace, technical, organisational and—in certain situations—also personal protective measures shall be implemented according to the applicable regulations. The efficiency of the implemented protective measures shall be checked by verification of their efficiency.

The effects can be considered on the basis of the structure of welding fumes (see also Sect. 2.2), as they are gaseous or in the form of particulate matters.

Epidemiological studies and animal tests with ultrafine particles non specifically connected with welding are in principle inhalation tests with rats or other rodents exposed to diesel soot, to technical soot and other particles to evaluate the effect of the size of particles independent of the chemical composition. They show that, depending on the particle surface in contact with the lung, inflammatory, fibrotic (hardening of the lung tissue) or carcinogenic effects may occur.

To minimise the health hazard to the welder posed by hazardous substances encountered in the workplace, engineering, administrative organisational and—in certain situations—personal protective measures, shall be implemented. The effectiveness of the implemented protective measures shall be verified.

Exposure to the bicyclic aromatic hydrocarbon naphthalene occurs in most cases along with other polycyclic aromatic hydrocarbons. Here we report from an investigation of 63 healthy, non-smoking male employees in the abrasives industry where naphthalene is the only relevant chemical exposure. Exposure assessment was performed using a combination of Air and Biological Monitoring over nearly a whole working week (Mo.–Th.). Air measurements were carried out during the shift on Thursday with the GGP mini-sampling system, combining particle and vapour sampling at low flow rates. In urine spot samples, the metabolites 1- and 2-naphthol were measured Mo.–Th. pre- and post-shift (for the reference group only Mo. pre- and Th. post-shift). With regard to naphthalene concentrations measured in air and concentrations of its metabolites (1- and 2-naphthol) in urine, study participants could be divided into a high and a low exposure group, and a reference group. The naphthalene concentration in air was in the range of 0.1–11.6 mg m−3, and naphthol concentrations (sum of 1- and 2-naphthol) in post-shift urine were in the range of

Welders have an increased susceptibility to airway infections with non-typeable Haemophilus influenzae (NTHi), which implicates immune defects and might promote pneumonia and chronic obstructive pulmonary disease (COPD). We hypothesized that welding-fume exposure suppresses Th1-lymphocyte activity. Non-effector CD4+ T-cells from blood of 45 welders (n = 23 gas metal arc welders, GMAW; n = 16 tungsten inert gas welders, TIG; n = 6 others) and 25 non-welders were ex vivo activated towards Th1 via polyclonal T-cell receptor stimulation and IL-12 (first activation step) and then stimulated with NTHi extract or lipopolysaccharide (LPS) (second activation step). IFNγ and IL-2 were measured by ELISA. In the first activation step, IFNγ was reduced in welders compared to non-welders and in the GMAW welders with higher concentrations of respirable particles compared to the lower exposed TIG welders. IFNγ was not influenced by tobacco smoking and correlated negatively with welding-fume exposure, respirable manganese, and iron. In the second activation step, NTHi and LPS induced additional IFNγ, which was reduced in current smokers compared to never smokers in welders as well as in non-welders. Analyzing both activation steps together, IFNγ production was lowest in smoking welders and highest in never smoking non-welders. IL-2 was not associated with any of these parameters. Welding-fume exposure might suppress Th1-based immune responses due to effects of particulate matter, which mainly consists of iron and manganese. For responses to NTHi this is strongest in smoking welders because welding fume suppresses T-cell activation towards Th1 and cigarette smoke suppresses the subsequent Th1-response to NTHi via LPS. Both effects are independent from IL-2-regulated T-cell proliferation. This might explain the increased susceptibility to infections and might promote COPD development.

To investigate the risk of lung cancer after exposure to welding fumes, hexavalent chromium (Cr(VI)), and nickel, we analyzed 3,418 lung cancer cases and 3,488 controls among men from 2 German case-control studies (1988–1996). We developed a welding-process exposure matrix from measurements of these agents, and this was linked with welding histories from a job-specific questionnaire to calculate cumulative exposure variables. Logistic regression models were fitted to estimate odds ratios with confidence intervals conditional on study, and they adjusted for age, smoking, and working in other at-risk occupations. Additionally, we mutually adjusted for the other exposure variables under study. Overall, 800 cases and 645 controls ever worked as regular or occasional welders. Odds ratios for lung cancer with high exposure were 1.55 (95% confidence interval (CI): 1.17, 2.05; median, 1.8 mg/m3 × years) for welding fumes, 1.85 (95% CI: 1.35, 2.54; median, 1.4 μg/m3 × years) for Cr(VI), and 1.60 (95% CI: 1.21, 2.12; median, 9 μg/m3 × years) for nickel. Risk estimates increased with increasing cumulative exposure to welding fumes and with increasing exposure duration for Cr(VI) and nickel. Our results showed that welding fumes, Cr(VI), and nickel might contribute independently to the excess lung cancer risk associated with welding. However, quantitative exposure assessment remains challenging.

The International Agency for Research on Cancer classified welding fumes as carcinogenic to humans, and occupational exposure limits should be established to protect welders. The aim of this study is to estimate exposure levels to inhalable and respirable welding fumes by welding process to use them for exposure assessment in epidemiological studies and to derive occupational exposure limits. In total, 15,473 mass concentrations of inhalable and 9,161 concentrations of respirable welding fumes could be analyzed along with welding-related and sampling information, which were compiled in the German database MEGA between 1983 and 2016. In both particle-size fractions, model-based geometric means of the concentrations were estimated by welding process and material for frequently used welding processes adjusted for sampling time and median-centered for calendar years. The inhalable concentrations were approximately twice the respirable concentrations, with medians of 3 mg/m3 (inter-quartile range: 1.2–7.0 mg/m3) and 1.5 mg/m3 (inter-quartile range: < limit of detection −3.8 mg/m3), respectively. The adjusted geometric means of flux-cored arc welding, metal inert and active gas welding, shielded metal arc welding and torch cutting ranged from 0.9 to 2.2 mg/m3 for respirable welding fumes and from 2.3 to 4.7 mg/m3 for inhalable fumes. In both particle-size fractions, geometric means were between 0.1 and 0.9 mg/m3 when performing tungsten inert gas, autogeneous, resistance, laser, and plasma welding or spraying. Results derived from this large dataset are useful for a quantitative exposure assessment to estimate health risks of welders.

Lead (Pb) is a recognized neurotoxin. Pb2+ can interfere with divalent metal transporters and ion channels and may thus affect other brain metals and cation signaling in neurons. Thereby, cognitive and sensory functions can be impaired. Whereas cognitive effects are well described less is known about olfaction and motor functions in the general population at currently lower exposure levels. The objective of this study was to evaluate the influence of Pb in blood (PbB) on odor identification and fine motor skills within the framework of the Heinz Nixdorf Recall Study (HNRS), a prospective cohort study among an elderly German population. Data on odor identification assessed with Sniffin’ sticks and fine motor test results were collected during the second follow-up of HNRS (2011–2014) in 1188 elderly men aged 55 to 86 years. PbB was determined in 1140 blood samples archived at baseline (2000–2003) and in 796 samples from the second follow-up. The association between PbB and impaired odor identification (normosmia as reference) was estimated with proportional odds ratios (PORs) with 95% confidence intervals (CI). The odds ratios (OR) of substantially impaired dexterity (tapping hits 90th percentile) were estimated with mixed logistic regression models for test results with both hands, where PbB was adjusted for covariates. PbB at baseline (median 32.9 μg/L; 2.27% ≥90 μg/L) was higher than at follow-up (25.9 μg/L; 0.84% ≥90 μg/L). The individual concentrations were correlated (Spearman rs 0.59, 95% CI 0.54 – 0.63). PORs of an impaired odor identification in men with baseline PbB ≥90 μg/L were 1.96 (95% CI 0.94–4.11) and 1.57 (95% CI 0.47–5.19) with follow-up PbB. Fine-motor tests were not affected by elevated PbB with the exception of tapping in men with follow-up PbB ≥50 μg/L (OR 2.14, 95% CI 1.09–4.23). Increasing age had strong effects on all outcomes. Low education was associated with impaired odor identification, tapping, and aiming. Also, alcohol consumption and current smoking affected the test results, particularly steadiness. In this community-based cohort of elderly men, we could confirm indication of an influence of elevated PbB on odor identification. Small numbers of men with elevated PbB due to an on-going trend of decreasing PbB in the general population, strong covariates and multiple comparisons hamper the evaluation of adversity of these effects of PbB on olfaction and dexterity.

Objectives Exposure to nickel (Ni) is widely distributed in the production and processing of steel or alloys. We compiled concentrations of inhalable Ni together with information about the duration of the measurement, analytical method, and workplace characteristics in the MEGA database. Methods This analysis was based on 8052 personal measurements of inhalable Ni collected between 1990 and 2009. Mixed-effects models were applied to the log-transformed Ni concentrations with imputed non-detects to assess the geometric means (GMs) of exposure to Ni in the various occupational settings adjusted by duration of sampling and calendar year. Results Most of measurements (38%) were collected in welders, which we further detailed by welding technique. Major predictor of the concentration was the technique and material in welding-related tasks. Highest exposure levels were estimated for welding materials of high Ni content with gas metal arc welding (48 μg/m 3 ; 95% CI 32–72 μg/m 3 ) and shielded metal arc welding (37 μg/m 3 ; 95% CI 24–57 μg/m 3 ). Furthermore, high GMs were estimated in metal sprayers (33 μg/m 3 ), in the manufacture of batteries (27 μg/m 3 ) and in forging-press operators (25 μg/m 3 ). We did not observe time trends of exposure to Ni in this period. Conclusion Ni concentrations varied considerably between occupations and were influenced by process and Ni content of consumables in welders. In order to assess exposure to Ni in community-based studies, supplemental information on job tasks, processes and materials is essential in addition to job titles.

The aim of this study was to estimate average occupational exposure to inhalable nickel (Ni) using the German exposure database MEGA. This database contains 8052 personal measurements of Ni collected between 1990 and 2009 in adjunct with information on the measurement and workplace conditions. The median of all Ni concentrations was 9 μg/m3 and the 95th percentile was 460 μg/m3. We predicted geometric means (GMs) for welders and other occupations centered to 1999. Exposure to Ni in welders is strongly influenced by the welding process applied and the Ni content of the used welding materials. Welding with consumable electrodes of high Ni content (>30%) was associated with 10-fold higher concentrations compared with those with a low content (

This study aimed to estimate occupational exposure to inhalable hexavalent chromium (Cr(VI)) using the exposure database MEGA. The database has been compiling Cr(VI) concentrations and ancillary data about measurements at German workplaces. We analysed 3659 personal measurements of inhalable Cr(VI) collected between 1994 and 2009. Cr(VI) was determined spectrophotometrically at 540 nm after reaction with diphenylcarbazide. We assigned the measurements to pre-defined at-risk occupations using the information provided about the workplaces. Two-thirds of the measurements were below the limit of quantification (LOQ) and multiply imputed according to the distribution above LOQ. The 75th percentile value was 5.2 μg/m(3) and the 95th percentile was 57.2 μg/m(3). We predicted the geometric mean for 2h sampling in the year 2000, and the time trend of Cr(VI) exposure in these settings with and without adjustment for the duration of measurements. The largest dataset was available for welding (N = 1898), which could be further detailed according to technique. The geometric means were above 5 μg/m(3) in the following situations: spray painting, shielded metal arc welding, and flux-cored arc welding if applied to stainless steel. The geometric means were between 1 μg/m(3) and 5 μg/m(3) for gas metal arc welding of stainless steel, cutting, hard-chromium plating, metal spraying and in the chemical chromium industry. The exposure profiles described here are useful for epidemiologic and industrial health purposes. Exposure to Cr(VI) varies not only between occupations, but also within occupations as shown for welders. In epidemiologic studies, it would be desirable to collect exposure-specific information in addition to the job title.

Cellular fatty acid-binding proteins (FABP) are a highly conserved family of proteins consisting of several subtypes, among them the mammary-derived growth inhibitor (MDGI) which is quite homologous to or even identical with the heart-type FABP (H-FABP). The FABPs and MDGI have been suggested to be involved in intracellular fatty acid metabolism and trafficking. Recently, evidence for growth and differentiation regulating properties of MDGI and H-FABP was provided. Using four affinity-purified polyclonal antibodies against bovine and human antigen preparations, the cellular localization of MDGI/H-FABP in human and mouse tissues and organs was studied. The antibodies were weakly cross-reactive with adipose tissue extracts known to lack H-FABP, but failed to react by Western blot analysis with liver-type FABP (L-FABP) and intestinal-type FABP (I-FABP). MDGI/H-FABP protein was mainly detected in myocardium, skeletal and smooth muscle fibres, lipid and/or steroid synthesising cells (adrenals, Leydig cells, sebaceous glands, lactating mammary gland) and terminally differentiated epithelia of the respiratory, intestinal and urogenital tracts. The results provide evidence that expression of H-FABP is associated with an irreversibly postmitotic and terminally differentiated status of cells. Since all the antisera employed showed spatially identical and qualitatively equal immunostaining, it is suggested that human, bovine and mouse MDGI/H-FABP proteins share highly homologous epitopes.

Mammary gland development is controlled by systemic hormones and by growth factors that might complement or mediate hormonal action. Peptides that locally signal growth cessation and stimulate differentiation of the developing epithelium have not been described. Here, we report that recombinant and wild-type forms of mammary-derived growth inhibitor (MDGI) and heart-fatty acid binding protein (FABP), which belong to the FABP family, specifically inhibit growth of normal mouse mammary epithelial cells (MEC), while growth of stromal cells is not suppressed. In mammary gland organ culture, inhibition of ductal growth is associated with the appearance of bulbous alveolar end buds and formation of fully developed lobuloalveolar structures. In parallel, MDGI stimulates its own expression and promotes milk protein synthesis. Selective inhibition of endogenous MDGI expression in MEC by antisense phosphorothioate oligonucleotides suppresses appearance of alveolar end buds and lowers the beta-casein level in organ cultures. Furthermore, MDGI suppresses the mitogenic effects of epidermal growth factor, and epidermal growth factor antagonizes the activities of MDGI. Finally, the regulatory properties of MDGI can be fully mimicked by an 11-amino acid sequence, represented in the COOH terminus of MDGI and a subfamily of structurally related FABPs. This peptide does not bind fatty acids. To our knowledge, this is the first report about a growth inhibitor promoting mammary gland differentiation.

Journal of occupational medicine and toxicology : JOMT 5(15), (2010). doi:10.1186/1745-6673-5-15, Published by BioMed Central Ltd., London

Objectives To assess level and trend of exposure to hexavalent chromium (Cr(VI)) in chromium-exposed occupations for the estimation of lung cancer risks in community-based studies. Method This analysis was based on 3666 personal measurements and auxiliary data compiled in the German MEGA database from 1988–2009. Cr(VI) was determined spectrophotometrically at 540 nm after reaction with diphenylcarbazide. We assigned jobs tasks with known Cr(VI) exposure using coded and textual information about the workplaces. Measurements below the limit of quantification (LOQ) were multiply imputed according to their distribution above LOQ. Statistical modelling was performed to the log-transformed Cr(VI) concentrations to adjust for duration and reason of sampling. Results Cr(VI) exposure could be assessed for eight out of 30 jobs tasks with known Cr(VI) exposure. The majority of measurements (53%) were collected in welders (N = 1930), which we further detailed by welding technique. Spray painting and the welding of stainless steel with shielded metal welding were associated with adjusted geometric means above 5 µg/m 3 , the permissible exposure level of the U.S. Occupational Safety and Health Administration. We could not detect an overall time trend in the Cr(VI) concentrations. Conclusions Exposure to Cr(VI) varied by occupation and job task, particularly between welding techniques, but less across calendar time. Supplemental occupational questionnaires should be administered in community-based studies when estimating the lung cancer risk of Cr(VI).

The epidermal growth factor receptor (EGFR) is overexpressed in about 48% of human breast cancer tissues. To analyse the role of the EGFR in mammary tumor development we generated transgenic mice expressing the human EGFR under the control of either the MMTV-LTR (MHERc) or the beta-lactoglobulin promoter (BLGHERc). The BLGHERc-transgene was expressed exclusively in the female mammary gland, whereas the MHERc transgene was expressed more promiscuously in other organs, such as ovary, salivary gland and testis. Female virgin and lactating transgenic mice of both strains have impaired mammary gland development. Virgin EGFR transgenic mice developed mammary epithelial hyperplasias, whereas in lactating animals progression to dysplasias and tubular adenocarcinomas was observed. In both strains the number of dysplasias increased after multiple pregnancies. The transgene expression pattern was heterogeneous, but generally restricted to regions of impaired mammary gland development. Highest EGFR transgene expression was observed in adenocarcinomas. By using a whole mount organ culture system to study the differentiation potential of the mammary epithelium, we observed a reduced number of fully developed alveoli and a decrease in whey acidic protein expression. Taken together, EGFR overexpression results in a dramatic effect of impaired mammary gland development in vitro as well as in vivo, reducing the differentiation potential of the mammary epithelium and inducing epithelial cell transformation.

Attempts were made to correlate growth effects induced by oestradiol and tamoxifen with the hormonal regulation of c-erbB-2 protein in experiments in vivo. We report here the responsiveness of four xenotransplanted oestrogen-receptor(ER)-positive and four ER-negative human mammary carcinomas to oestradiol and tamoxifen. Oestradiol in a dose of 0.5 mg/kg significantly increased the growth of the ER-positive mammary carcinomas 3366, MCF-7, 4134 and 4049, but not the ER-negative tumours 4000, 4296 and MT-3. However, within the group of the ER-negative breast carcinomas the tumour 4151 ES deviates from this growth behaviour, as we could prove an estrogen induced growth. The stimulation of tumour growth by oestradiol was always accompanied by a down-regulation of c-erbB-2 protein both in the ER-positive mammary carcinomas and in the ER-negative mammary carcinoma 4151 ES. Tamoxifen significantly inhibited the growth of the ER/PR-positive mammary carcinomas 3366 and MCF-7 but not the ER-positive/PR-negative mammary carcinomas 4049 and 4134. In the group of ER-negative mammary carcinomas only the growth of the oestrogen-responsive tumour 4151 ES was significantly inhibited by tamoxifen. The inhibition of tumour growth by tamoxifen was correlated with a reversion of the oestradiol-induced down-regulation of c-erbB-2, also in the ER-negative/oestradiol-responsive mammary carcinoma 4151 ES. From our results we hypothesize that the oestrogen-dependent growth of ER-negative breast carcinoma 4151 ES could also be correlated with the oestradiol-regulated expression of c-erbB-2 protein.

A method for the cultivation of organ explants from abdominal mammary glands of virgin mice has been established. In a serum-free medium containing aldosterone, prolactin, insulin, and cortisol (APIH medium) mammary gland development was documented by lobuloalveolar morphogenesis. The hormonal requirements for in vitro expression of beta-casein and of the mammary-derived growth inhibitor (MDGI) were tested. To this end, a full length cDNA coding for mouse MDGI was prepared displaying strong homologies to a mouse heart fatty acid binding protein, which is also expressed in the mammary gland. MDGI and beta-casein transcripts were found to be absent in the mammary tissue from primed virgin mice, and were induced upon culture of mammary explants in the APIH medium. An immunohistochemical analysis with specific antibodies against MDGI and casein revealed a different pattern of expression for the two proteins. In the APIH medium, MDGI was expressed mainly in differentiating alveolar cells of the lobuloalveolar structures, whereas beta-casein was present in both ductules and alveoli. The relationship between functional differentiation and MDGI expression was further studied in explants from glands of late-pregnant mice. At this stage of development, MDGI is found both in ducts and in alveoli. If explants were cultured with epidermal growth factor (EGF) and insulin, the lobuloalveolar structure was still present, whereas MDGI disappeared. Reinduction of MDGI expression was achieved by subsequent PIH treatment. Independent on developmental stage, EGF strongly inhibits MDGI mRNA expression. It is concluded that MDGI-expression is associated with functional differentiation in the normal gland.

Eine Therapie der Amyloidosen erscheint theoretisch durch Beeinflussung amyloidogener Faktoren, Hemmung der Amyloidsynthese, Verhinderung der extracellularen fibrillaren Pracipitation oder der Auflosung bereits abgelagerten Amyloids moglich. Experimentell wurde bisher der Einflus von Medikamenten (vor allem Glykocorticoiden, Chemotherapeutica und Antibiotica), physikalischen (Rontgenbestrahlung) und chirurgischen Masnahmen (Thymektomie, Splenektomie) untersucht. Potentiell wirksam sind Verbindungen bzw. Eingriffe mit transskriptionshemmendem oder RES-stimulierendem Effekt. Korrelationen zu ihrer immunsuppressiven oder -steigernden Wirkung ergeben sich nicht. Eine therapeutisch verwertbare induzierte Lyse von Amyloidfibrillen ist nach den derzeitigen Erfahrungen nicht moglich, obwohl an ihrer Resorbierbarkeit kein Zweifel besteht.