Interphase cytogenetics reveals a high incidence of aneuploidy and intra-tumour heterogeneity in breast cancer

The occurrence of aberrations involving chromosomes 11 and 17 in malignant tissues of breast cancer patients has not yet been studied systematically. Using fluorescence in situ hybridisation (FISH) with centromere-specific probes, we determined chromosome 11 and 17 status in interphase nuclei from primary and/or metastatic breast cancer cells. In all cancerous specimens obtained from 30 patients, FISH identified cells with clonal chromosomal abnormalities, with aneuploidy rates ranging from 6% to 92% (median 59%). There was a gain of centromeric signals for chromosome 11, most likely corresponding to hyperploidy; aberrations of chromosome 17 in specimens from 26 patients (87%) were hyperploid as well; however, four cases (13%) showed loss of chromosome 17 centromeres. All specimens contained heterogeneous aneuploid cell populations with excessive gain of signals in some cases. The pattern of aneuploidy did not appear to correlate with tumour grade/stage and was comparable in primary tumours and corresponding metastatic axillary lymph nodes, indicative of genetic instability early in tumour development. Screening with a panel of FISH probes may lead to enhanced sensitivity and specificity in detecting malignant cells, as demonstrated in this study with effusions which could not be conclusively interpreted as being malignant by cytological criteria.

Preoperative characterization of pigmented skin lesions by epiluminescence microscopy and high-frequency ultrasound

BACKGROUND AND DESIGN

Previous studies have referred to the value of epiluminescence microscopy in the differential diagnosis of pigmented skin lesions and to the possibility of preoperative tumor thickness measurement in malignant melanoma by high-frequency ultrasound. Both noninvasive methods have been combined in this study. The question of improved diagnostic accuracy was discussed. Previously proposed epiluminescence microscopic characteristics of 508 melanocytic lesions and sonographic characteristics of 792 skin tumors were investigated for their sensitivity and specificity. The tumor thickness of 108 malignant melanomas was measured sonographically.

RESULTS

Black dots, irregular pigment network, and grayish-blue areas have been shown to be the most sensitive characteristics, whereas pseudopods, grayish-blue areas, and a whitish veil have been shown to be the most specific epiluminescence microscopic features for malignant melanoma. Sonography alone cannot reliably distinguish between different skin tumors. Preoperatively, the tumor thickness of 85% of the melanomas was assessed correctly concerning the pT stage.

CONCLUSIONS

A 20-MHz ultrasound, in addition to epiluminescence microscopy, may improve the diagnostic accuracy by delivering information about depth and topographic location of skin tumors, but cannot give highly specific information about tissue dignity. It is a reliable tool for tumor thickness measurement for surgical planning.

High-performance liquid chromatographic determination of the rhamnolipids produced by Pseudomonas aeruginosa

The bacterial biosurfactants 3-[3'-(L-rhamnopyranosyloxy)decanoyloxy]decanoic acid (RL-1) and 3-[3'-(2"-O-alpha-L-rhamnopyranosyl-alpha-L-rhamnopyranosyloxy) decanoyloxy]decanoic acid (RL-2) were isolated from Pseudomonas aeruginosa DSM 2659 cultures. An HPLC method was developed for the p-bromophenacyl esters of the rhamnolipids. Separation was obtained within 25 min on a RP C18 column using a linear gradient of water-acetonitrile (30:70 to 0:100) and UV detection (265 and 320 nm). Linearity of response existed for 1.2-25 microg of the RL-1 and 1.8-25 microg of the RL-2-p-bromophenacyl ester (0.9-19.2 microg RL-1 and 1.3-18.0 microg RL-2). The reproducibility of the entire analytical method (extraction, derivatisation) was tested.

Tissue polypeptide-specific antigen (TPS) in monitoring palliative treatment response of patients with gastrointestinal tumours

The new proliferation marker, tissue polypeptide-specific antigen (TPS), representing the specific epitope M3 of tissue polypeptide antigen, and three conventional biochemical markers, CEA, CA 19-9 and CA-195, were analysed in 69 patients with advanced gastrointestinal tumours. The aim of our study was to assess the clinical relevance of these markers and to determine whether their use in monitoring the course of the disease can reduce the need for serial imaging procedures. At baseline, pathologically elevated TPS levels occurred in 90% of patients. CEA was elevated in 73%, CA 19-9 in 59% and CA-195 in 68%. With a detection rate of > 90% in both advanced colorectal (n = 37) and pancreatic cancer (n = 20), and of 75% in gastric cancer (n = 12), TPS was the most sensitive marker in all three tumour types included in this analysis. Serial evaluations of TPS and other biochemical markers were available in 39 patients undergoing palliative systemic chemotherapy. Treatment with a fluorouracil-based regimen resulted in a partial response in 5/27 patients with colorectal cancer, whereas 2/12 patients with pancreatic cancer responded to therapy with a high-dose epirubicin combination regimen. All other patients had disease stabilisation or suffered from progressive disease. When compared with the results of serial CT scanning, the TPS correlated best with the course of the disease, the positive predictive value being 75% for a partial response, 96% for stable disease and partial response combined and 100% for progressive disease. The corresponding values for CEA were 50%, 81% and 62% and were similar to those for CA 19-9 and CA-195. In summary, TPS seems to represent a sensitive, clinically relevant and specific marker of proliferative activity in gastrointestinal cancer. According to our preliminary results in colorectal and pancreatic cancer, TPS may be considered as the primary means of monitoring treatment, and imaging reduced to confirm the response.

Statistical analysis of vibration-induced bone and joint damages

Vibration-induced damages to bones and joints are still occupational diseases with insufficient knowledge about causing and moderating factors and resulting damages. For a better understanding of these relationships also retrospective analyses of already acknowledged occupational diseases may be used. Already recorded detailed data for 203 in 1970 to 1979 acknowledged occupational diseases in the building industry and the building material industry of the GDR are the basis for the here described investigations. The data were gathered from the original documents of the occupational diseases and scaled in cooperation of an industrial engineer and an industrial physician. For the purposes of this investigations the data are to distinguish between data which describe the conditions of the work place (e.g. material, tools and posture), the exposure parameters (e.g. beginning of exposure and latency period) and the disease (e.g. anamnestical and radiological data). These data are treated for the use with sophisticated computerized statistical methods. The following analyses were carried out. Investigation of the connections between the several characteristics, which describe the occupational disease (health damages), including the comparison of the severity of the damages at the individual joints. Investigation of the side dependence of the damages. Investigation of the influence of the age at the beginning of the exposure and the age at the acknowledgement of the occupational disease and herewith of the exposure duration. Investigation of the effect of different occupational and exposure conditions.

Investigations of the suitability of pallesthesiometry in the diagnostics of functional disturbances of the peripheral nervous system

This contribution presents the results of fundamental investigations of the suitability of measurements of vibration sensitivity threshold (pallesthesiometry) as a method for the assessment of vibration-induced nerve impairments. Sinusoidal vibration stimuli are applied at the fingertips of the subjects in this method. The sensitivity threshold of the subjects is determined similar like the hearing threshold in audiometry and is used as a measure for possibly existing nerve disorders. Laboratory and field experiments were carried out by means of a simple to serve and inexpensive pallesthesiometer. The test results proved the suitability of the pallesthesiometry for screening purposes in principle. Concentration and cooperation of the subjects as well as the suitable selection of the investigation frequencies according to the frequency content of the vibration exposure are of essential meaning for comparable and reliable measuring results. Furthermore the rest and vibration-free position of the hand and fingers during the measurement of the thresholds are important to avoid measurement falsifications. A most extensive standardization of the investigation methodology and of the measuring equipment as well as the establishment of normative values of the sensitivity thresholds for different age groups are necessary for a broad application of the pallesthesiometry in practice.

Pharmacokinetic interaction between epirubicin and the multidrug resistance reverting agent D-verapamil

The potential for a pharmacokinetic interaction between epirubicin and the second-generation multidrug resistance modulating agent D-verapamil (DVPM) has been investigated in six patients with advanced colorectal cancer. Our results indicate that a significant interaction takes place. Enhanced distribution of epirubicin from the serum and altered disposition might, in fact, explain the increased level of myelotoxicity in this pilot as well as in other clinical phase II studies involving DVPM.

Effective second line chemotherapy of advanced breast cancer with navelbine and mitomycin C

The efficacy and toxicity of navelbine 30 mg/m2 administered intravenously (IV) over 30 minutes every 3 weeks, and mitomycin C 15 mg/m2 administered IV every 6 weeks was assessed in 34 patients with metastatic breast cancer refractory to first-line chemotherapy. An overall objective response rate of 35% was achieved (95% confidence interval, 20% to 53%), with an additional 47% of patients maintaining stable disease (SD). Four of 12 patients who responded had received previous anthracycline therapy. Median time to progression for responders and patients with SD was 6.3 months. The median survival of all patients was 8.8 months. Tolerance of this regimen was remarkable. WHO grade 3/4 side effects consisted of granulocytopenia in 12% and thrombocytopenia in 15%, and included only 1 patient each with grade 3 neurotoxicity and local toxicity due to extravasation. Delay of treatment was required for hematologic toxicity in 7 patients, and 5 required dose reductions. In conclusion, navelbine/mitomycin C is an active and well-tolerated regimen that may be considered for second-line treatment. If our results are confirmed by larger analyses of other patients studies, this combination might also warrant further exploration in combination with other active agents for front line chemotherapy of advanced breast cancer.

[Peculiarities of occupational health vibration measurements of manually controlled banging machines]

Specific problems of the measurement of mechanical vibrations on the grips of hand-held tools are discussed in this paper. Especially the measurement on percussive-typ tools, e.g. pneumatic hammers, percussive drills and others, is focussed. The possibilities of affecting the measuring results because of mistakes in the measurement procedure and because of technological peculiarities of the working process are explained and hints for minimizing these influences are given.

Mechanism of enzymatic dehalogenation of pentachlorophenol by Arthrobacter sp. strain ATCC 33790

Pentachlorophenol (PCP) dehalogenase from Arthrobacter sp. strain ATCC 33790 converts PCP to tetrachlorohydroquinone. In labeling experiments with H(2)18O or 18O2, only with H(2)18O was labeled product found. However, unlabeled tetrachlorohydroquinone became labeled after incubation with the enzyme in H(2)18O. Therefore, distinction between an oxygenolytic or a hydrolytic dehalogenation mechanism for the PCP dehalogenase is not possible.

Enzymatic dehalogenation of pentachlorophenol by extracts from Arthrobacter sp. strain ATCC 33790

Arthrobacter sp. strain ATCC 33790 was grown with pentachlorophenol (PCP) as the sole source of carbon and energy. Crude extracts, which were prepared by disruption of the bacteria with a French pressure cell, showed no dehalogenating activity with PCP as the substrate. After sucrose density ultracentrifugation of the crude extract at 145,000 x g, various layers were found in the gradient. One yellow layer showed enzymatic conversion of PCP. One chloride ion was released per molecule of PCP. The product of the enzymatic conversion was tetrachlorohydroquinone. NADPH and oxygen were essential for this reaction. EDTA stimulated the enzymatic activity by 67%. The optimum pH for the enzyme activity was 7.5, and the temperature optimum was 25 degrees C. Enzymatic activity was also detected with 2,4,5-trichlorophenol, 2,3,4-trichlorophenol, 2,4,6-trichlorophenol, and 2,3,4,5-tetrachlorophenol as substrates, whereas 3,4,5-trichlorophenol, 2,4-dichlorophenol, 3,4-dichlorophenol, and 4-chlorophenol did not serve as substrates.