[Robotic-assisted mobilization for an effective mobilization in a COVID-19 patient with ECMO treatment]

An effective (early) mobilization in COVID-19 intensive care patients with ECMO treatment is very important. Sedation, extracorporeal procedures with the danger of circuit malfunction, large lumen ECMO cannulas with a risk of dislocation and a very severe neuromuscular weakness are factors that could deem mobilization beyond stage 1 of the ICU mobility score (IMS) in some cases difficult or impossible; however, early mobilization is a key point of the ABCDEF bundle to counteract pulmonary complications, neuromuscular dysfunction and enable recovery. The case of a 53-year-old, previously healthy and active male patient with a severe and complicated course of COVID-19 and pronounced ICU-acquired weakness is described. While receiving ECMO the patient could be mobilized using a robotic system. Due to severe and rapidly progressing pulmonary fibrosis, additional low-dose methylprednisolone therapy (Meduri protocol) was implemented. Under this multimodal treatment the patient was successfully weaned from the ventilator and decannulated. Robotic-assisted mobilization has the potential to be a novel and safe therapeutic option for a customized and highly effective mobilization in ECMO patients.

Harmonizing and supporting infection control training in Europe

Healthcare-associated infection (HCAI), patient safety, and the harmonization of related policies and programmes are the focus of increasing attention and activity in Europe. Infection control training for healthcare workers (HCWs) is a cornerstone of all patient safety and HCAI prevention and control programmes. In 2009 the European Centre for Disease Prevention and Control (ECDC) commissioned an assessment of needs for training in infection control in Europe (TRICE), which showed a substantial increase in commitment to HCAI prevention. On the other hand, it also identified obstacles to the harmonization and promotion of training in infection control and hospital hygiene (IC/HH), mostly due to differences between countries in: (i) the required qualifications of HCWs, particularly nurses; (ii) the available resources; and (iii) the sustainability of IC/HH programmes. In 2013, ECDC published core competencies for infection control and hospital hygiene professionals in the European Union and a new project was launched ['Implementation of a training strategy for infection control in the European Union' (TRICE-IS)] that aimed to: define an agreed methodology and standards for the evaluation of IC/HH courses and training programmes; develop a flexible IC/HH taxonomy; and implement an easily accessible web tool in 'Wiki' format for IC/HH professionals. This paper reviews several aspects of the TRICE and the TRICE-IS projects.

Training infection control and hospital hygiene professionals in Europe, 2010: agreed core competencies among 33 European countries

The harmonisation of training programmes for infection control and hospital hygiene (IC/HH) professionals in Europe is a requirement of the Council recommendation on patient safety. The European Centre for Disease Prevention and Control commissioned the 'Training Infection Control in Europe' project to develop a consensus on core competencies for IC/HH professionals in the European Union (EU). Core competencies were drafted on the basis of the Improving Patient Safety in Europe (IPSE) project's core curriculum (CC), evaluated by questionnaire and approved by National Representatives (NRs) for IC/HH training. NRs also re-assessed the status of IC/HH training in European countries in 2010 in comparison with the situation before the IPSE CC in 2006. The IPSE CC had been used to develop or update 28 of 51 IC/HH courses. Only 10 of 33 countries offered training and qualification for IC/HH doctors and nurses. The proposed core competencies are structured in four areas and 16 professional tasks at junior and senior level. They form a reference for standardisation of IC/HH professional competencies and support recognition of training initiatives.

[Outbreak with Ralstonia pickettii caused by contaminated magnesium vials]

HISTORY

In February 2013, 5 patients in an intensive care unit (ICU) were found to have positive blood cultures with Ralstonia pickettii within one week. Because all patients got intravenous therapy, improper work of a staff member was suspected. Some days later, a 6th patient was found with a positive blood culture of Ralstonia pickettii in another department of the hospital.

INVESTIGATIONS

Hygienic investigations showed no evidence of failures in preparation of intravenous therapy. All patients were on different intravenous drugs, but every patient had received glucose 5 % and magnesium. We examined samples of glucose and magnesia as well as samples from environment. RESULTS AND COURSE: Glucose and magnesium samples were examined by membrane filter method. Ralstonia pitteckii was detected in some Magnesium vials. We concluded, that contamination of Magnesium vials might have been the reason for blood stream infection of patients. Pharmacists and authorities were informed and all vials were collected and replaced by vials from another company. Later a nationwide recall of Magnesium vials was performed by the producing company. No further Ralstonia pickettii was found in blood cultures in our hospital.

CONCLUSION

Unusual pathogens in blood cultures should lead to reflection of rarer causes such as contamination of medicines.

[Evaluation of time, attendance of medical staff, and resources during stereotactic radiotherapy/radiosurgery : QUIRO-DEGRO Trial]

BACKGROUND

The German Society of Radiation Oncology ("Deutsche Gesellschaft für Radioonkologie", DEGRO) initiated a multicenter trial to develop and evaluate adequate modules to assert core processes and subprocesses in radiotherapy. The aim of this prospective evaluation was to methodical assess the required resources (technical equipment and medical staff) for stereotactic radiotherapy/radiosurgery.

MATERIAL AND METHODS

At two radiotherapy centers of excellence (University Hospitals of Heidelberg and Marburg/Giessen), the manpower and time required for the implementation of intra- and extracranial stereotactic radiotherapy was prospectively collected consistently over a 3-month period. The data were collected using specifically developed process acquisition tools and standard forms and were evaluated using specific process analysis tools.

RESULTS

For intracranial (extracranial) fractionated stereotactic radiotherapy (FSRT) and radiosurgery (RS), a total of 1,925 (270) and 199 (36) records, respectively, could be evaluated. The approximate time needed to customize the immobilization device was median 37 min (89 min) for FRST and 31 min (26 min) for RS, for the contrast enhanced planning studies 22 and 27 min (25 and 28 min), for physical treatment planning 122 and 59 min (187 and 27 min), for the first and routine radiotherapy sessions for FSRT 40 and 13 min (58 and 31 min), respectively. The median time needed for the RS session was 58 min (45 min). The corresponding minimal manpower needed was 2 technicians for customization of the immobilization device, 2.5 technicians and 1 consultant for the contrast-enhanced planning studies, 1 consultant, 0.5 resident and 0.67 medical physics expert (MPE) for physical treatment planning, as well as 1 consultant, 0.5 resident, and 2.5 technicians for the first radiotherapy treatment and 2.33 technicians for routine radiotherapy sessions.

CONCLUSION

For the first time, the resource requirements for a radiotherapy department for the maintenance, protection and optimization of operational readiness for the application of intra- and extracranial stereotactic radiotherapy was determined methodically.

[Managing EHEC in hospital routine]

BACKGROUND

During May and June 2011 an outbreak of enterohemorrhagic Escherichia coli (EHEC) occurred in Germany. More than 4000 patients were infected of which 800 developed hemolytic uremic syndrome (HUS) as a severe complication. Reports in the press led to great concern in the general population. Many people with diarrhea reported to hospitals in order to exclude EHEC infections.

METHODS

We describe the management of patients with suspected infectious diarrhea at the university hospital of Essen. A hospital with a significant number of immunocompromised patients.

RESULTS

One important measure to handle the surge of contagious patients was to establish a multidisciplinary coordination team under leadership and guidance of the Department of Nephrology and the Department of Hospital Hygiene. Suspected infectious patients were separated in a modified emergency room. A new ward for infectious diseases was established to isolate in-patients.

CONCLUSION

In our hospital the management of EHEC outbreak enabled us to treat these additional infectious patients without hampering the treatment of the other patients. As a result we plan the implementation of a coordination team for future epidemics.

Evaluation of time, attendance of medical staff, and resources during radiotherapy for breast cancer patients. The DEGRO-QUIRO trial

BACKGROUND AND PURPOSE

To conform to recommendations regarding the treatment of breast cancer, an estimation of costs and personnel to assure treatment is required. To date no recommendations based on real time measurements are available. The DEGRO (German Society of Radiation Oncology), therefore, initiated a prospective multicenter evaluation of core procedures of radiotherapy. In this analysis, the results regarding human resources and room occupation during the treatment of breast cancer are presented.

PATIENTS AND METHODS

Three academic radiation oncology centers (Erlangen, Münster, Mannheim) prospectively documented their workflow and working time for all breast cancer patients from July-October 2008. Subsequently, a statistical analysis was performed.

RESULTS

The longest working time of physicians was the definition of the target volume and organs at risk (mean 33 min). Furthermore, physicians needed much time for general tasks, which included conversations. Physicists needed the most time for treatment planning and authorization (64 min), whereas technicians were mostly needed in day-to-day radiotherapy treatment (15 min, 31 min including verification). Despite significant differences in specific steps between centers, overall working times and room occupation were comparable and representative. Special procedures (intraoperative radiotherapy/multicatheter brachytherapy) required considerable amounts of additional working time of physicians and physicists.

CONCLUSION

In this prospective analysis, data of human resources and room occupation during treatment of breast cancer are presented for the first time. Each patient consumes about 12 h of human resources for treatment and 3.75 h for general tasks (physicians 4.7 h, physicists 1.8 h, and technicians 9.2 h).

Time management in radiation oncology: development and evaluation of a modular system based on the example of rectal cancer treatment. The DEGRO-QUIRO trial

PURPOSE

The goal was to develop and evaluate a modular system for measurement of the work times required by the various professional groups involved in radiation oncology before, during, and after serial radiation treatment (long-term irradiation with 25-28 fractions of 1.8 Gy) based on the example of rectal cancer treatment.

MATERIALS AND METHODS

A panel of experts divided the work associated with providing radiation oncology treatment into modules (from the preparation of radiotherapy, RT planning and administration to the final examination and follow-up). The time required for completion of each module was measured by independent observers at four centers (Rostock, Bamberg, Düsseldorf, and Offenbach, Germany).

RESULTS

A total of 1,769 data sets were collected from 63 patients with 10-489 data sets per module. Some modules (informed consent procedure, routine treatments, CT planning) exhibited little deviation between centers, whereas others (especially medical and physical irradiation planning) exhibited a wide range of variation (e.g., 1 h 49 min to 6 h 56 min for physical irradiation planning). The mean work time per patient was 12 h 11 min for technicians, 2 h 59 min for physicists, and 7 h 6 min for physicians.

CONCLUSION

The modular system of time measurement proved to be reliable and produced comparable data at the different centers. Therefore, the German Society of Radiation Oncology (DEGRO) decided that it can be extended to other types of cancer (head and neck, prostate, and breast cancer) with appropriate modifications.

Outbreak due to a Klebsiella pneumoniae strain harbouring KPC-2 and VIM-1 in a German university hospital, July 2010 to January 2011

We describe the epidemiology and characteristics of the pathogen and patients (n=7) associated with an outbreak of a carbapenem-resistant Klebsiella pneumoniae (CRKP) strain in a German university hospital from July 2010 to January 2011. Species identification and detection of carbapenem resistance were carried out using standard microbiological procedures. Carbapenemases were detected by phenotypic methods and specific polymerase chain reactions (PCRs). DNA fingerprinting profiles were performed with repetitive sequence-based PCR. Medical records of colonised or infected patients were retrospectively reviewed. Antibiotic resistance profiles, PCR-specific amplification products and genotyping demonstrated that the outbreak occurred because of the spread of a single CRKP clone harbouring both KPC-2 and VIM-1. Five of the seven patients had invasive infections with the CRKP strain; the deaths of four of them were directly related to the infection. Early implementation of infection control interventions brought about efficient containment of further cross-transmission. Rapid dissemination of carbapenemase-producing Enterobacteriaceae is a serious concern in patient care and is a problem that has emerged in western Europe.

Outbreak due to a Klebsiella pneumoniae strain harbouring KPC-2 and VIM-1 in a German university hospital, July 2010 to January 2011

We describe the epidemiology and characteristics of the pathogen and patients (n=7) associated with an outbreak of a carbapenem-resistant Klebsiella pneumoniae (CRKP) strain in a German university hospital from July 2010 to January 2011. Species identification and detection of carbapenem resistance were carried out using standard microbiological procedures. Carbapenemases were detected by phenotypic methods and specific polymerase chain reactions (PCRs). DNA fingerprinting profiles were performed with repetitive sequence-based PCR. Medical records of colonised or infected patients were retrospectively reviewed. Antibiotic resistance profiles, PCR-specific amplification products and genotyping demonstrated that the outbreak occurred because of the spread of a single CRKP clone harbouring both KPC-2 and VIM-1. Five of the seven patients had invasive infections with the CRKP strain; the deaths of four of them were directly related to the infection. Early implementation of infection control interventions brought about efficient containment of further cross-transmission. Rapid dissemination of carbapenemase-producing Enterobacteriaceae is a serious concern in patient care and is a problem that has emerged in western Europe.

[Waste management in hospitals. Current situation in the state of North Rhine-Westphalia]

In 20 hospitals in North Rhine-Westphalia in-plant handling wastes and the delivery of the waste to the disposer were examined. Deficits were seen regarding risk assessment and operating instructions, support by company doctors, personal protection equipment, and break areas for the waste collecting personnel. Also the qualification of the waste management officer and his/her time contingent, correct declaration of the wastes, the training of the waste collecting personnel, the cleaning of multi-use containers and transportation vehicles, storage of the wastes at the collecting points, and the use of sharp collecting boxes were to be partly criticized. Consequences and recommendations are given, concerning the company's obligations (e.g., provide risk assessment, operating instructions), waste management officer (e.g., qualification, enough time contingent, regular inspections), waste collecting personnel (e.g., training courses), industrial safety (e.g., protection equipment, break area wash places), company doctors, transportation vehicles in the house (e.g., regular cleaning), one-way collectors (e.g., labelling at the site of the collection), multi-use collectors (e.g., cleaning), and compressing containers (e.g., larger maintenance openings).

Environmental sampling of particulate matter and fungal spores during demolition of a building on a hospital area

Demolition or renovation works adjacent to hospitals pose risks of fungal airborne infections. During November 2005 and March 2006 an old building with three floors was demolished on the area of University Hospital of Essen. To prevent dust exposure the building was sealed up by impermeable plastic foil and mechanical disruption of structures was accomplished using excavators. Dust emission was minimised by water jet. To determine if there were any infectious risks for patients from emissions from the demolition work we monitored particle and fungal concentration of the air before and during demolition. Air sampling was performed at seven positions around the building and weather conditions were monitored at the same time. Concentrations of ultrafine particles, particles > or =0.3, > or =0.5 and > or =1 microm were significantly higher during demolition than before, but only by small factors (ultrafine particles 1.6-fold, particles > or =0.3 microm 1.6-fold, particles > or =0.5 microm 2.9-fold and particles > or =1 microm 3.3-fold). Concentrations of moulds which could be cultured at 37 degrees C did not differ between the two periods (median before demolition: 66 cfu/ m3; median during demolition: 80 cfu/m3). Concentrations of moulds which grew at 22 degrees C correlated significantly with temperature and humidity and were significantly higher before (median: 510 cfu/m3) than during the demolition period (median: 210 cfu/m3). We conclude that the fungal infection risks for patients during demolition work in hospital areas is not increased by demolition if protective measures are in place.

Success of MRSA eradication in hospital routine: depends on compliance

BACKGROUND

To prevent transmission of MRSA, eradication by antiseptic washings and nasal ointment is recommended. There are few studies, which investigated the success of eradication of MRSA carriage during everyday clinical working conditions and results are controversial. We wanted to assess the effectiveness of MRSA eradication procedures--especially octenidine whole body washings and mupirocin nasal ointment--under conditions of everyday life.

PATIENTS AND METHODS

We retrospectively analyzed the files of all patients who were admitted to the medical department of a tertiary care hospital between 1999 and 2004 and who were infected or colonized by MRSA. According to hospital's standards of care patients should have been washed with octenidine and should have got mupirocin nasal ointment only in case of nasal carriage. Patients were regarded as MRSA-eradicated when swabs taken on three consecutive days, earliest, three days after discontinuation of antiseptic and antiinfective procedures were without proof of MRSA.

RESULTS

Only 6% of patients were eradicated. MRSA could be cultured from swabs taken on dismissal of 60% of patients. Fifteen percent of patients had only one or two negative series of swabs. In 19% of patients success of eradication remained unknown. Besides we found that under every day clinical working conditions compliance with several tasks of the eradication protocol was insufficient.

CONCLUSION

Under every day clinical working conditions MRSA eradication is successful only in few patients. Whole body washings should be tested in detailed studies before they should become a recommendation for eradication of MRSA.

[Hygiene in home care. A study with home care providers]

We studied the implementation of infection control guidelines of 9 providers of home care in the German Ruhr area. The study included 22 nurses, and 214 home care patients were seen. The following main problems were identified: Qualified infection control staff is lacking, infection control protocols are lacking or are not adapted, the cooperation with family doctors often is problematic, there are deficits in hand hygiene and great deficits with clothing hygiene and waste disposal. We suggest improvements for some care tasks, e.g., handling of urinary catheters, infusions and prescription of tracheostomy tubes.

[Experiences with anthrax emergency measures during 2001 and 2002 in the city of Essen]

After the terrorist attacks of 11 September 2001 suspected cases of anthrax also occurred in Germany. No case could be confirmed. From October 2001 to November 2002 the fire brigade of the city of Essen was called in 110 cases of suspected anthrax contamination. In 78 cases specimens were transported to diagnostic laboratories, in 22 cases persons were transported. Only in the first few days patients with suspected contamination had to stay in hospital and underwent chemoprophylaxis. Cooperation between the fire brigade, the local health authorities and the hygienists of the involved hospitals was very intense. It seems necessary to evaluate all the German experiences with suspected anthrax cases to develop risk estimations for different exposure situations and to develop specific recommendations for decontamination, disinfection and initial therapy.

Fire eater's risk: lipoid pneumonia following aspiration of a liquid hydrocarbon mixture

Acute aspiration of a liquid hydrocarbon mixture by fire eaters may cause severe lipoid pneumonia. The toxic effect of ingested hydrocarbon chains depends on their length and biophysical qualities. We report the case of a patient who accidentally aspirated a hydrocarbon liquid resulting in a lipoid pneumonia. The pathomechanism, diagnostic work-up, and the therapeutic approach are discussed.

[Occupational lead poisoning due to deficient protective measures at the work place]

Occupational lead poisoning due to deficient protective measures at the work place.

HISTORY AND ADMISSION FINDINGS

A 27-year-old man who was working in the mixing plant of a company manufacturing synthetic materials, was admitted with colicky upper abdominal pain, loss of appetite and postprandial nausea for 3 weeks. On examination he had pain without guarding over the abdomen.

INVESTIGATIONS

He had a normochronic anaemia (haemoglobin 12.5. g/dl). Ultrasound of the abdomen revealed splenomegaly. Gastroscopy excluded an ulcer. Deep duodenal biopsy showed Giardia intestinalis histologically.

DIAGNOSIS, TREATMENT AND COURSE

As part of the differential diagnosis of abdominal colic and anaemia, lead poisoning was found, with the lead level markedly elevated to 1776 microgram/l. Penicillamine treatment rapidly reduced the blood lead level, but it had not yet become normal after 4 months. Exposure to lead at his work place was discovered. Subsequent tests there by the federal agency for occupational protection revealed massive deficiencies in protective measures.

CONCLUSION

In present conditions abdominal colic must be viewed as a cardinal symptom of lead poisoning. Blood levels must be obtained as part of the differential diagnosis of abdominal pain of uncertain aetiology. If the diagnosis has been established and an occupational risk is possible, the appropriate occupational organizations and, if necessary, federal agency must be informed in order to exclude occupational exposure to lead. In Germany there still exist marked deficiencies in the protection of workers occupationally exposed to lead. Notification is essential to protect others similarly at risk.

Biomarkers of genetic damage and inflammation in blood and bronchoalveolar lavage fluid among former German uranium miners: a pilot study

Former East German uranium miners who are known to have been exposed to radon are estimated to be at high risk for lung carcinogenesis. Among these miners over 200 occupationally caused lung cancer cases are expected to occur each year, resulting in a total of 7,000-24,000 excess lung cancer cases in the coming years. It is still unknown whether there is a correlation between biomarkers and the exposure of the uranium miners to ionizing radiation that might enable us to trace those miners with high lung cancer risk. The primary aim of this pilot study was to test the possibility of performing a biomarker study in this unique cohort of former uranium miners in spite of several limitations that had to be taken into consideration when comparing them with healthy controls, such as old age, age-dependent diseases and potential confounding artefacts from dissimilar smoking patterns. The second aim was to test a range of biomarkers for DNA damage and inflammation in leukocytes and bronchoalveolar fluid for their ability to detect biological effects. In this cohort of miners we found an increased frequency of chromosomal aberrations in blood lymphocytes and an increased prevalence of both fibronectin and tumour necrosis factor alpha in the bronchoalveolar fluid.

Efficiency of continuous positive airway pressure versus theophylline therapy in sleep apnea: comparative sleep laboratory studies on objective and subjective sleep and awakening quality

Sleep apnea is the most common sleep-related breathing disorder characterized by repetitive episodes of hypoxemia. Therapies include behavioral, surgical, orthodontic, pneumological, and pharmacological interventions. The aim of the present study was to compare the efficiency of pneumological therapy by nasal continuous positive airway pressure (CPAP) versus a pharmacological approach with theophylline (Respicur retard(R) 400 mg) on respiratory variables as well as objective and subjective sleep and awakening quality in patients with moderate sleep apnea measured by polysomnography and psychometry. Under CPAP therapy all respiratory variables improved and normalized, while under theophylline only the apnea-hypopnea index and the desaturation index improved but still did not return to normal values. Regarding sleep initiation and maintenance, CPAP therapy prolonged sleep latency and reduced movement time, while patients treated with theophylline showed reduced total sleep period, total sleep time and sleep efficiency. Sleep architecture demonstrated an increase in deep sleep and REM stages under CPAP therapy, and remained unchanged under theophylline. Concerning subjective sleep and awakening quality, both treatments improved well-being in the morning. Regarding objective awakening quality, reaction time performance was improved in both groups. In conclusion, CPAP treatment is more effective than theophylline regarding respiratory variables as well as the normalization of sleep maintenance and sleep architecture in sleep apnea patients.

p53 mutations and codon 213 polymorphism of p53 in lung cancers of former uranium miners

PURPOSE

There is a high prevalence of G-->T transversions of p53 in lung cancers of smokers. One study has reported a special "hotspot" mutation at codon 249 of p53 in lung cancers of former uranium miners. The aim of our study was to look for mutational spectra of p53 in former German uranium miners with lung cancers.

METHODS

We investigated 16 patients with lung cancer who had worked as uranium miners in Germany and 13 lung cancer patients without a mining history of the same region. By means of the polymerase chain reaction and sequencing we looked for mutations in exons 5 7 of the p53 gene.

RESULTS

We could not find any suggestion of hotspot mutations. The only G-->T mutation in former uranium miners was detected in the only nonsmoker. In 3 patients (19% of the total) we found a codon 213/3 polymorphism.

CONCLUSIONS

The results indicate that G-->T transversions do not seem to be very common mutations in p53 in lung cancers probably caused by radiation. Therefore, p53 may be mutated early in lung cancer development if radiation exposure is a critical factor in carcinogenesis. In accordance with studies of thyroid cancer patients in the Chernobyl region, our results may indicate an overrepresentation of codon 213/3 polymorphism in p53 in radiation-caused cancers.

Elevated DNA single-strand breakage frequencies in lymphocytes of welders exposed to chromium and nickel

DNA damage (alkaline filter elution) and sister chromatid exchange (SCE) frequencies were measured in lymphocytes of 39 welders and 39 controls. The welders showed a significantly higher rate of DNA single-strand breakages and significantly elevated SCE values. These results are not in accordance with those of a former study in which only DNA-protein cross-links were measured. The different results may be explained on the basis of different exposure levels for chromium(VI) and nickel. Both methods are not specific but sensitive enough to measure genotoxic damage after occupational exposure to chromium(VI) and nickel in the range of threshold values for the workplace on a collective basis. Additionally, the results indicate that DNA single-strand breakage and DNA-protein cross-links show different increases depending on the exposure levels for chromium and nickel.

[Geriatric assessment--the Vienna model]

Geriatric Assessment is a structured interdisciplinary process for the diagnosis of the functional status and potential for rehabilitation of geriatric inpatients. This paper describes the possibilities and scope of the Vienna Model of Geriatric Assessment oriented in terms of practicability and focused implementation of resources. By using this multidimensional proceeding the rehabilitation-quotient of patients has increased more than 39%. From this point of view Geriatric Assessment in a geriatric hospital is a practical instrument to prevent hospitalization, to increase survival at home, and to improve functional status in elderly patients.

DNA single strand breakage, DNA adducts, and sister chromatid exchange in lymphocytes and phenanthrene and pyrene metabolites in urine of coke oven workers

OBJECTIVES

To investigate the specificity of biological monitoring variables (excretion of phenanthrene and pyrene metabolites in urine) and the usefulness of some biomarkers of effect (alkaline filter elution, 32P postlabelling assay, measurement of sister chromatid exchange) in workers exposed to polycyclic aromatic hydrocarbons (PAHs).

METHODS

29 coke oven workers and a standardised control group were investigated for frequencies of DNA single strand breakage, DNA protein cross links (alkaline filter elution assay), sister chromatid exchange, and DNA adducts (32P postlabelling assay) in lymphocytes. Phenanthrene and pyrene metabolites were measured in 24 hour urine samples. 19 different PAHs (including benzo(a)pyrene, pyrene, and phenanthrene) were measured at the workplace by personal air monitoring. The GSTT1 activity in erythrocytes and lymphocyte subpopulations in blood was also measured.

RESULTS

Concentrations of phenanthrene, pyrene, and benzo(a)pyrene in air correlated well with the concentration of total PAHs in air; they could be used for comparisons of different workplaces if the emission compositions were known. The measurement of phenanthrene metabolites in urine proved to be a better biological monitoring variable than the measurement of 1-hydroxypyrene. Significantly more DNA strand breaks in lymphocytes of coke oven workers were found (alkaline filter elution assay); the DNA adduct rate was not significantly increased in workers, but correlated with exposure to PAHs in a semiquantitative manner. The number of sister chromatid exchanges was lower in coke oven workers but this was not significant; thus counting sister chromatid exchanges was not a good variable for biomonitoring of coke oven workers. Also, indications for immunotoxic influences (changes in lymphocyte subpopulations) were found.

CONCLUSIONS

The measurement of phenanthrene metabolites in urine seems to be a better biological monitoring variable for exposure to PAHs than measurement of hydroxypyrene. The alkaline filter elution assay proved to be the most sensitive biomarker for genotoxic damage, whereas the postlabelling assay was the only one with some specificity for DNA alterations caused by known compounds.

Biomonitoring of urinary aromatic amines and arylamine hemoglobin adducts in exposed workers and nonexposed control persons

The renal excretion of arylamines in occupationally exposed and nonexposed subjects was measured by a gas chromatography-electron capture detector method. Additionally, in the occupationally exposed persons hemoglobin adduct levels of arylamines were determined by a liquid chromatography-electrochemical detector method, together with the individual acetylator status. The aromatic amines aniline, p-toluidine, 2-naphthylamine, and 4-chloro-o-toluidine were detected in the urine of nonsmoking subjects who were not occupationally exposed to arylamines. Significantly higher concentrations of aniline, o-toluidine, m-toluidine, 2-naphthylamine, and 4-methyl-1,3-phenylenediamine could be observed in the urine of smoking control persons in comparison to nonsmokers. Comparison of smokers and nonsmokers in a group of workers primarily exposed to aniline and 4-chloroaniline revealed significant differences (P < 0.05) in the formation of 4-aminodiphenyl hemoglobin adducts and in the renal excretion of 2-naphthylamine. The slow acetylators in this group produced significantly more hemoglobin adducts of aniline and 4-chloroaniline than did the fast acetylators. In slow acetylators among the smoking workers there was a significant increase in the formation of 4-aminodiphenyl hemoglobin adducts and in the renal excretion of 4-chloroaniline and m-toluidine. The results indicate that there are influences of smoking habits and acetylator status on the levels of arylamine hemoglobin adducts as well as urinary arylamine concentrations. Hemoglobin adducts seem to be good parameters for monitoring aniline and 4-chloroaniline exposure at the workplace, especially if the acetylator polymorphism can be taken into account. 4-Aminodiphenyl hemoglobin adducts might be good parameters for monitoring individual smoking habits. The determination of urinary arylamine concentrations provides additional information concerning acute exposures to aromatic amines.

[New data on syncarcinogenesis in tumors of exogenous origin]

Little is known about syncarcinogenic effects of occupational and environmental substances although it is supposed that different exogenous factors may play critical roles in the development of many human tumors. Epidemiologic results prove syncarcinogenesis for asbestos exposure and smoking (lung cancer), radon exposure and smoking (lung cancer), exposure to aromatic amines and smoking (bladder cancer) and alcohol abuse and smoking (oral, larynx and oesophagus cancer). Animal experiments point to additive effects in carcinogenesis for different nitrosamines and substances like benzo(a)pyrene, carbon tetrachloride, ethanol, vinyl chloride and ionising radiation. It can be concluded from modern concepts of carcinogenesis that syncarcinogenic mechanisms may not only result from genotoxicity but also from influences on cell proliferation and mitogenesis as well as toxicokinetics, DNA repair, intercellular communication, immune system and hormonal effects. New methods of molecular epidemiology seem very promising to study syncarcinogenic effects in animals and humans.

The metameric pattern of the head mesoderm--does it exist?

It is a long-standing question whether the paraxial head mesoderm of vertebrate embryos is segmentally organized into somites like the trunk or not. On the one hand, no somites are seen in the anterior head mesoderm in vertebrate embryos, on the other hand, such a segmental pattern has been described under the name of somitomeres. In order to investigate the patterning of mesodermal cells in the head of avian embryos we performed scanning electron microscopy, computer assisted reconstructions of the head mesoderm and density analyses of head mesoderm cells. We observed regional differences within the head mesoderm of avian embryos, but we could not see a consistent somitomeric pattern in the head mesoderm. In sum, we consider that the avian head mesoderm is not arranged in a metameric pattern.

Comparison of the single breath with the intrabreath method for the measurement of the carbon monoxide transfer factor in subjects with and without airways obstruction

BACKGROUND

Measurement of the carbon monoxide transfer factor (TLCO) has traditionally been performed using the single breath method but recently the intrabreath method has been developed. The aim of this study was to compare the two methods in the clinical evaluation of patients with obstructive and non-obstructive pulmonary disorders.

METHODS

Measurements of TLCO with the intrabreath method were carried out on a study sample composed of 50 patients with non-obstructive disorders and 50 with airways obstruction (FEV1/FVC < 70%) either before or after a single breath measurement of the TLCO had been performed. The method involves the continuous analysis of a single slow expirate using a computerised rapid multigas infrared analyser. TLCO, alveolar volume (VA), TLCO/VA, and inspired vital capacity (IVC) values were obtained for both groups by both methods.

RESULTS

When measured with the intrabreath method the group with airways obstruction showed lower TLCO and TLCO/VA values than the non-obstructive group. VA was higher in both patient groups when measured with the intrabreath technique. The same test also showed higher TLCO values with the intrabreath method in the group with non-obstructive disorders and lower TLCO/VA values with the intrabreath method in those with airways obstruction. The corresponding parameters obtained by the two methods correlated closely, with no correlation between the magnitude of the differences with the magnitude of the readings. An index of gas mixing indicated a better distribution of the inspired air for the intrabreath method than for the single breath method. The VA values obtained with the intrabreath method showed a closer agreement to the actual total lung capacities measured by body plethysmography.

CONCLUSION

The intrabreath method of determining TLCO is comparable to the traditional single breath method. Measurement of alveolar volume by the intrabreath method approximates more closely to total lung capacity, even in subjects with airways obstruction.