Analysis of the genotoxic activity of four N-nitroso compounds by the Drosophila mosaic test.

Mutagenic activity of 4 nitroso compounds of environmental importance - N-nitroso-morpholine, dinitrosopiperazine, N,N'-dinitroso-pyridinol-carbamate and N-methyl-N-nitroso-p-toluenesulfonamide - was tested by the Drosophila mosaic test. Larvae were fed with the nitroso-compound-containing food for 2-4 days, and when they had developed into adults, their wings were screened for mosaic spots. All 4 compounds were positive. This finding supports the conclusion that the mosaic test - besides other test procedures - may become a tool for identifying mutagens.

Cytogenetic effect of the thiocarbamate herbicides butylate, molinate and vernolate in the mouse bone marrow micronucleus test.

Three thiocarbamate herbicides, butylate (S-ethyl-diisobutylthiocarbamate), vernolate (S-propyl dipropylthiocarbamate) and molinate (S-ethyl-N,N-hexamethylenethiocarbamate) were assayed for cytogenetic effect in the mouse bone marrow micronucleus test. Butylate was inactive in bone marrow, vernolate caused a marginal increase in the incidence of micronucleated polychromatic erythrocytes only at a high toxic dose level. Molinate, the N,N-hexamethylene derivative was, however, strongly active in the bone marrow, causing a high frequency of micronucleated erythrocytes, even at subtoxic concentrations.

Long-term carcinogenicity bioassay of the herbicide atrazine in F344 rats.

In Fischer F344/LATI rats of both sexes the herbicide atrazine was given in the diet at concentrations of 0, 375 and 750 ppm for 126 weeks. Food and water consumption was similar in the treated and control groups. Feeding of atrazine resulted in dose-dependent depression of body weight gain in both sexes. There was no difference in the survival among the females. The males in the treated groups lived significantly longer than the controls. Exposure to atrazine resulted in significantly increased incidence of mammary tumors in the high dose male group. Uterine carcinomas were observed at a dose-related, significantly increased incidence. The number of combined leukemias/lymphomas increased in the treated males and females, but it was statistically significant only for females. The total number of malignant tumors showed a dose-related increase in both sexes. Other tumors and nontumorous lesions occurred at background level and were not influenced by treatment.

Changes of chloroplast ultrastructure and carbohydrate level in festuca, achillea and sedum during drought and after recovery.

The changes of chloroplast ultrastructure and carbohydrate level in C(4) sclerophyllous Festuca vaginata, C(3) malacophyllous Achillea ochroleuca and CAM succulent Sedum sexangulare were investigated during naturally induced drought and after subsequent recovery. Chloroplasts of the species show some characteristic changes due to drought: decreased volume, permanent adhesions within the grana, partitions become thinner, lipid droplets increase in number and size. Contraction of the stroma, swelling and blistering of thylakoids are characteristic of Sedum chloroplast and mesophyll chloroplasts of Festuca. Structure of bundle sheath chloroplasts of C(4) Festuca scarcely shows changes during drought and after recovery. During drought and subsequent recovery in the chloroplasts onf Achillea the slightest changes of the stromal and grana lamellae region can be observed. During drought starch grains are characteristic of chloroplasts of Achillea and Sedum; they disappear after recovery. Achillea and Sedum leaves contain more starch during drought than after recovery, while the starch content in Festuca is unchanged. There is more soluble sugar in Festuca and Sedum during drought than after recovery, although the amount of soluble sugar in Achillea is decreased during drought.

Different electrophoretypes of human rotaviruses in Hungary.

Polyacrylamide gel electrophoresis of rotaviral double-stranded ribonucleic acid (RNA) extracted directly from faecal specimens collected in three different parts of Hungary was applied to characterize and distinguish 21 randomly selected viral isolates. This technique made it possible to define 7 different electrophoretypes. Of the isolates 11 exhibited an identical "long" electrophoretic migration pattern. "Short" RNA pattern was found in two cases, and one atypical rotavirus was also revealed. This is the first description of rotavirus RNA electrophoretypes in Hungary.

Genotoxicity of selected herbicides.

Twenty-two herbicides were studied in 67 tests for induction of DNA damage, gene mutation and chromosomal changes in vitro and in vivo. Triazine and urea-type herbicides were found to be inactive in all but one test. Of 4 thiocarbamates, molinate and vernolate caused chromosomal changes, namely increased incidence of sister chromatid exchanges and chromosomal aberrations in vitro and increased frequency of micronucleated polychromatic erythrocytes in mouse bone marrow. These compounds, however, did not cause gene mutation and only molinate gave equivocal positive result in bacterial repair test. Out of 11 miscellaneous herbicides, ethofumesate, alachlor, dichlorprop and fluorodifen proved to be positive only in one or two tests. In the light of clastogenicity of some thiocarbamates, serious consideration should be given to start animal carcinogenicity studies with these chemicals.

Mutagenicity and PAH content of airborn particulates and of fallen dusts from two Hungarian towns and emission samples from aluminum reduction and power plants.

Urban air particulates (suspended particles and settling dust), furthermore dust emitted by a Soderberg aluminum reduction plant and a coal burning power plant from an industrial town, Ajka (30,000 inhabitants) were analysed for PAH content (liquid chromatography) and mutagenicity (Salmonella microsome test). Air particulates from Papa--a town of similar size without considerable heavy industry--and corresponding plant emission from Inota, a third town in the study, served as controls. The dust content and the PAH concentration, as well as the mutagenic potency of the air in Ajka were higher than in Papa. Mutagenicity of the airborne particulates showed a clear seasonality with a winter maximum and a summer minimum in both towns. The mutagenic potency of air correlated well with the air BaP and total PAH content in Ajka, but not in Papa. The amounts of extractable organic material and mutagenic potency as calculated for unit quantity of airborne particulate matter was higher in the Papa samples. Similar differences between the two towns were observed in the case of fallen dust, too. On the basis of examination of emitted dust, it can be stated, that in the mutagenicity of urban air, the aluminum plant emission plays a considerably higher role than the power plant emission, which is the main component of air dust pollution in Ajka.

[First isolation of Borrelia burgdorferi (Lyme spirochaeta) from ticks in Hungary]. / A Borrelia burgdorferi (Lyme spirochaeta) elsö hazai izolálása kullancsokból.

31 field collected Ixodes ricinus adult ticks were investigated for the Lyme-disease spirochete. 5/31 Ixodes ricinus contained Borrelia burgdorferi. The spirochete was successfully cultivated in four cases, and they were found in two ticks by immunofluorescence technique and dark field microscopy, as well. Two of the isolated strains were tested by Western blot. The antigen pattern in both strains showed marked bands in 41 and 60 kD antigen, but only a week band appeared at 32 kD, with the lack of the OspB. The mechanism of infection and the way of prevention is discussed.

The influence of refractory ceramic fibres on pulmonary morphology, redox and immune system in rats.

Refractory ceramic fibres (RCF) were studied in male SPRD rats by both in vivo long term sequential and in vitro methods. RCF was administered by single intratracheal instillation and the lungs were examined at the end of months 1, 3 and 6 after exposure. In addition, the direct toxicity of the fibres was examined in a primary culture of alveolar macrophages (AM) and in pneumocytes type II (T2). Pulmonary morphological changes, a number of parameters of the redox system, such as activity of extracellular Cu,Zn/superoxide dismutase (EC-SOD), total glutathione content of the lungs (GSH) and immunoglobulins in bronchoalveolar lavage (IgA, IgG, IgM) and in the blood were measured. The composition of the original RCF and the elemental content of the lung tissue were compared by energy dispersive x-ray analysis (EDXA) before and after exposure. Macrophage alveolitis became confluent and moderate fibrosis developed by the end of month 3, and after 6 months of exposure the intensity decreased to the level of the first month. The RCF did not significantly influence the activity of EC-SOD or the total glutathione content of the lungs. Although aluminium and silicon could be demonstrated by EDXA in the lung tissue at the end of month 3, these elements were no longer detectable by the end of month 6. The RCF decreased IgA significantly in bronchoalveolar lavage (BAL). The main components of RCF induced pulmonary alterations, whereas no significant change could be detected in EC-SOD and GSH. Injuries caused by direct toxicity could be observed in the cell membranes only at the highest concentration. On the basis of these results RCF can be determined as moderately toxic fibres.

Induction of malignant lymphomas in swiss mice by n-nitroso compounds formed in vivo.

Malignant lymphomas were induced in Swiss mice treated intragastrically with methyl-2-benzimidazole carbamate (MBC, BCM, Carbendazim) and given sodium nitrite in their drinking water. The tumours appeared between 82 and 164 days after the beginning of treatment. In 30 mice given MBC and sodium nitrite, 10 lymphosarcomas were found. In the proliferating tumour cells, intracytoplasmic type-A virus particles were demonstrated by electron microscopy. No tumours were found in animals given MBC only. The findings demonstrate the possibility of in vivo formation of N-nitroso derivatives from MBC.

Incidence of enteritis of Enterobacteriaceae isolates possessing human colonization factor antigen. New human colonization factors.

Of 462 Enterobacteriaceae strains including 435 Escherichia coli isolated from 250 patients, 298 haemagglutinating (HA) cultures were classified into 36 different HA groups. Sixteen of them belonged to Evan's I or II groups, although none possessed CF I or CF II antigen detectable by slide agglutination. Seventy-seven strains showed 4+ mannose resistant (MR) HA with human (53), bovine (2), chicken (6), guinea pig (7) or human and guinea pig (9) erythrocytes. These strains were significantly more frequent in patients under one year of age. Eighty-eight percent of the typable strains belonged to E. coli serogroups O1, O2, O4, O6, O18. HA positivity and fimbrial structures were correlated in 2 isolates (15/1, O18a, c:-K77: H-; 12/2/1 O1: K1: H .). Fimbriae of the two strains exhibited adhesive properties. Their fimbrial antigens differed serologically from each other and from those of the reference strains H 10407 and PB 176. Forty-nine of 4+ human MRHA strains showed variable reactions in the two sera for the new fimbrial antigens.

Virulence factors of Escherichia coli. I. Mannose resistant haemagglutinating capacity is associated with serogroup but not with site of infection.

Different serogroups of Escherichia coli strains originating from faeces (patients with enteritis 244, healthy individuals 225), urine (pyelonephritis 111, cystitis 130, asymptomatic bacteriuria 59) and other extraintestinal sources (blood 30, cerebrospinal fluid 15, wound 13, autopsy material 9, umbilicus 8, vagina 20, throat 13 and nose swabs 5) were examined for mannose resistant haemagglutination of human A erythrocytes (MRHA hum.). The most frequent serogroups were O1, O2, O4, O6, O7, O18 and O75 uniformly among faecal (26.5%), urinary (34%) and other extraintestinal (57.9%) strains. Haemagglutinating activity was significantly more frequent in these serogroups than in others (p less than 0.001). There was no significant association between MRHA positivity and origin of the serogroups. It has been concluded that MRHA hum. property of an E. coli strain depends on its serogroup rather than its origin. As these serogroups are the most frequent in the intestinal flora, it is assumed that their physiological function is to colonize the bowel and their pathological significance is to provide a source for extraintestinal infection.

Virulence factors of Escherichia coli. III. Correlation with Escherichia coli pathogenicity of haemolysin production, haemagglutinating capacity, antigens K1, K5, and colicinogenicity.

A total of 1156 Escherichia coli strains including 489 faecal, 384 urinary, 283 other extraintestinal isolates was compared for haemolysin production (Hly), mannose resistant haemagglutinating activity (MRA), presence of antigens K1 and K5 and colicinogenicity (Col). K1 capsule which was demonstrated only in a few serogroups (O1, O2, O7, O18) occurred more frequently among extraintestinal (32.1%) than among faecal (4.3%) or urinary (7.3%) isolates. In the incidence of antigen K5 there was no difference between faecal and urinary (3.3%; 3.1%) or between urinary and other extraintestinal (5.3%) isolates belonging mainly to serogroups O2, O6, O18 and O75. Col+ isolates occurred frequently in all samples (23.5% of faecal, 31.7% of urinary and 43.4% of other extraintestinal strains), they being significantly more frequent in serogroups O1, O2, O7, O18 than in others. A close association existed between K1+ and Col+ properties, mainly (24.4%) among strains isolated from extraintestinal sources other than urine. The frequent coexistence of K1+ and Col+ in serogroups O1, O2, O7, O18 offers a further explanation for the extraintestinal pathogenicity of these serogroups. Neither Hly+ and K1+, nor Hly+ and Col+ were associated. MRA+ and K1+ correlated mainly in serogroups O1, O2 but never occurred simultaneously in serogroup O18. Connection between MRA+ and Hly+ was not associated with other virulence factors (K1, Col). The results showing a close connection among certain serogroups (O1, O2, O4, O6, O7, O18) and certain markers of pathogenicity (MRA, Hly, K1, Col) support the concept that E. coli strains have a clonal connection.

[A full-term second abdominal pregnancy]. / Donosena sekundarna abdominalna trudnoca.

A case is described of abdominal pregnancy in a 27-year-old patient with a previous salpingectomy of the right tube performed because of tubal pregnancy. The patient was hospitalized in the 22nd to the 28th week of pregnancy on suspicion of imminent abortion. Clinical and ultrasound examinations indicated intrauterine pregnancy, by just before the expected date of delivery, clinical symptoms suggested abdominal pregnancy. The oxytocin test was negative. Following laparotomy a live normal girl was born, weighting 3200 g. The placenta was inserted at the front wall and the right horn of the uterus from the outer side. In the right horn there was an opening at the site of the oviduct excision. Because of profuse bleeding, the uterus was amputated supravaginally.

Mutagenicity of emission and immission samples around industrial areas.

Urban air particulates (suspended particles and settling dusts), as well as dusts emitted by a Söderberg aluminium production plant and a coal-burning power plant, in the industrial town of Ajka were analysed for polycyclic aromatic hydrocarbon (PAH) content (liquid chromatography) and mutagenicity (Salmonella microsome test). The same parameters for air particulates from Pápa (a town of similar size without much heavy industry) were analysed and compared to those from Ajka. The dust content, PAH concentration and the mutagenic potency of the air in Ajka were higher than in Pápa. Mutagenicity of airborne particulates showed a clear seasonality with a winter maximum and a summer minimum in both towns. The mutagenic potency of air correlated well with the benzo[a]pyrene (BP) and PAH content in Ajka but not in Pápa. The amounts of extractable organic material and mutagenic potency, as calculated for unit quantity of airborne particulate matter, were higher in the Pápa samples. Similar differences between the two towns were observed in the case of deposited dust. As regards the emission dusts, the aluminium plant emissions are responsible for much more of the mutagenicity of the urban air than the power plant emission, which is the main component of air dust pollution in Ajka.

Inhibition by an antioxidant of the carcinogenic effect of nitrosomorpholine formed in vivo.

In earlier studies, it was found that the new antioxidant, MTDQ-DA ((6,6-methylene-bis)2,2-dimethyl-4-methane-sulphonic acid sodium salt-1,2-dihydroquinoline) (Patent No. 3172) prevented in vivo nitrosation and the acute hepatotoxicity of morpholine plus sodium nitrite in rats. The aim of the present experiments was to examine whether MTDQ-DA could decrease the frequency of tumours induced by simultaneous administration of morpholine and nitrite in the lung adenoma assay. Forty CFLP mice were used in each group and they were killed 8 months after treatment. In group A, treated with 1000 mg/kg morpholine i.g., and in Group B (untreated control) a similar frequency of lung adenomas could be observed (0.13 adenomas/mouse). After the combined i.g. treatment in Group C (MOR, 1000 mg/kg + nitrite, 125 mg/kg), the incidence of lung adenomas was found to be 16.58/mouse. A single dose of MTDQ-DA (500 mg/kg) added to the group C treatment reduced the lung adenoma frequency to 2.47/mouse (Group D). As MTDQ-DA shows neither toxic nor mutagenic effects and inhibits the in vivo nitrosation in both hepatotoxicity and lung adenoma assays, it may be considered to be a potential food additive.

Changes in phage-sensitivity of Shigella flexneri strains. II. The F-like character of Ms2-sensitive variants.

Variants sensitive to male specific phage Ms2 appeared among Ms2 non-sensitive Shigella flexneri cultures in the course of liquid medium passages. Sensitivity to Ms2 was lost on acridine orange treatment and was transferable into Ms2 non-sensitive variants. The Ms2 sensitive variants had fimbrial antigen. Electron microscopy showed that Ms2 phages were adsorbed on the F-like fimbriae of these variants. It was assumed that F-like plasmids determining F-like fimbrial antigen were carried by these variants.

Mutagenicity studies on terbacil, an uracil-analogue pesticide.

The possible mutagenic effect of the uracil analogue pesticide Terbacil was examined on Drosophila melanogaster and in mammalian cell culture. Terbacil did not prove to be mutagenic in the sex-linked recessive lethal mutation test, and it did not cause an increase in sister chromatid exchange in CHO cells. It cannot be considered a chromosome-mutagenic compound. Considering the procaryote studies known from the literature, it is assumed that Terbacil does not represent a genotoxic hazard for the persons involved either in its production or its use.