PROTEIN and RNA SYNTHESES and PRECURSOR UPTAKE WITH ISOLATED NERVE and GLIAL CELLS

Protein and RNA syntheses were investigated with bulk isolated nerve and glial cells from rabbit brain. For polypeptide synthesis, ‘intact’ cells were incubated with [³H]leucine under various conditions and the results were compared with those of polyribosomal polypeptide synthesis. For RNA synthesis ‘intact’ cells were incubated with [³H]uridine or [³H]guanosine and the results were compared with those of DNA-dependent RNA polymerase assay. The bulk isolated ‘intact’ nerve cells were more active in protein synthesis than the ‘intact’ glial cells, while the latter synthesized RNA more actively than the former, although both polyribosomal polypeptide synthesis and DNA-dependent RNA polymerase activity were higher with the nerve cells, indicating a higher potential for the nerve cells. The observed discrepancy of RNA synthesis was explained by the significantly less active uptake of nucleosides with the nerve cells. Both protein and RNA syntheses with ‘intact’ cells were sensitive to hypoxic or glucose-deficient conditions. While both the nerve and glial cells were sensitive to hypoxia to a similar extent, the nerve cells were more sensitive to glucose deficiency. It was suggested that the bulk isolated nerve and glial cells still retain certain integral cell functions as viable cells, and can be utilized for various physiological and pharmacological investigations provided caution is exercised in their application and in the interpretation of the results.     

Serum iron and copper status and oxidative stress in severe and mild preeclampsia

Our aim was to investigate parameters of iron and copper status and oxidative stress and antioxidant function in women with healthy pregnancy, mild and severe preeclampsia with a view to exploring the possible contribution of these parameters to the aetiology. Thirty healthy, 30 mild preeclamptic and 30 severe preeclamptic pregnant women were included. Serum and placental lipid peroxides, and serum vitamin E and total carotene levels were measured by colorimetric assay. Cholesterol, copper, iron, total iron binding capacity (TIBC), ceruloplasmin and transferrin concentrations were measured by commercially available procedures. Data were analysed statistically using one-way analysis of variance and Pearson correlation test. Logistic regression procedures were used to calculate odds ratios. Lipid peroxides in serum and placental tissue, and iron, copper and ceruloplasmin levels in serum were significantly increased, and transferrin, TIBC, vitamin E/total cholesterol and total carotene/total cholesterol ratios in serum were significantly decreased especially in women with severe preeclampsia. Significant correlations were detected between serum iron and lipid peroxides in serum and placental tissue and between serum iron and vitamin E/total cholesterol in severe preeclamptic pregnancy. Furthermore, there were significant correlations between serum malondialdehyde and ceruloplasmin and vitamin E/total cholesterol in women with severe preeclampsia, and changes in serum and placental lipid peroxides and serum iron concentrations were significantly associated with preeclampsia. In conclusion, ischaemic placental tissue may be a primary source of potentially toxic iron in preeclampsia and the released iron species may contribute to the aetiology and would exacerbate lipid peroxidation and endothelial cell injury, which may be abated by antioxidant supplementation.     

Occurrence and levels of indicators and selected pathogens in different sludges and biosolids

AIMS: Determine the occurrence and levels of pathogens and indicators in raw and treated sludges and compare their persistence after two different treatments. METHODS AND RESULTS: Helminth ova, Cryptosporidium spp., Salmonella spp., enteroviruses, and bacterial and viral indicators were determined in raw sludges and biosolids produced after mesophilic and thermophilic treatments. Except Salmonella, all of the parameters were quantified. Helminth ova were found at very low concentrations even in raw sludges. Viable Cryptosporidium oocysts were still present in most samples of treated sludges. Faecal coliforms, spores of sulphite-reducing clostridia (SSRC), and somatic coliphages were the only indicators with values above their detection limits in most of the samples. CONCLUSIONS: Pathogens were still detected in some treated sludge samples. SSRC were the most resistant micro-organisms to treatments and hence may be an indicator for the reduction of protozoan oocysts. Somatic coliphages constitute an alternative as viral indicators due to their detection in sludges before and after treatment. SIGNIFICANCE AND IMPACT OF THE STUDY: Because of the persistence of some pathogens after sludge treatments, additional indicators are needed. SSRC and somatic coliphages are good candidates. Easy and inexpensive methods for the determination of these indicators are feasible both in industrialized and developing countries.     

Hormones and behavior of prepubertal and peripubertal chimpanzees

Twenty-one chimpanzees ranging in age from 2.9 to 9.2 years at the midpoint of a study consisting of five 4-week blocks were studied behaviorally in four groups of five or six animals per group, balanced for age and sex. Blood samples for radioimmunoassay of follicle-stimulating hormone (FSH), luteinizing hormone, 17 beta-estradiol, testosterone, dehydroepiandrosterone (DHA), DHA sulfate (DHAS), and cortisol were obtained once each 4-week block. Sex differences were found only in the categories of play duration and initiative and genital inspection, all of which were greater for the males. Several categories (6) of play and other affiliative behaviors were negatively correlated with age and/or body weight for the males, whereas fewer of those categories (2) were so correlated in the females. Hierarchical behavior, genital inspection, solitary behavior other than play, and autogrooming were all positively correlated with age and/or body weight for the males, and only autogrooming for the females. FSH and testosterone levels and testicular volume were positively correlated with age and body weight in the males, whereas for the females cortisol was negatively correlated with body weight and only FSH and the ratios of DHA and DHAS to cortisol were positively correlated with age and/or body weight. Most of the behaviors that were significantly correlated with age and body weight for the males were also correlated in the same direction with FSH and testosterone levels and testicular volume, but not with DHA or DHAS levels. The data are consistent with the view that testosterone, but not the adrenal androgens DHA and DHAS, contributed to the behavioral development of the males. There were few significant correlations between hormones and behavior for the females and interpretation is not clear. The absence of age-related increases in DHA and DHAS of both the males and females, in contrast to the pattern of FSH (and testosterone for the males), supports the growing consensus that adrenarche and puberty are independent developmental processes. The absence of any strong correlations between behavior and levels of the adrenal androgens in either the males or females suggests that adrenarche per se is not a significant event in the behavioral development of chimpanzees.     

Molecular cloning and expression of glycoprotein IIb and IIIa

Objective To amplify the cDNA genes of GPIIb, GPIIIa, then construct the eukaryotic expression carriers of GPIIb and GPIIIa respectively, finally establish CHO cell lines stably expressing GPIIb and GPIIIa. Methods Human erythroleukemia (HEL) cells were cultured for total RNA extraction. RT-PCR was accomplished using the specific GPIIb, GPIIIa primers designed according to Genbank by Primer 5, then each of cDNAs were obtained. The expressive vector pcDNA3.1(+) and PCR products were cut by NheI and HindIII, and then the fragements were directly cloned to pcDNA3.1(+) because of having the same adhesive ends. Then pcDNA3.1(+)IIb and pcDNA3.1(+)IIIa were transfected into CHO cells respectively by Lipofectamine 2000. The cell lines expressing GPIIb, GPIIIa were screened by G418. Then the Chinese hamster ovary (CHO) cell lines were examed through flow cytometry (FCM) and RT-PCR to detect the expression of GPIIb, GPIIIa in CHO cells. Results The cDNAs of GPIIb and GPIIIa were amplidied by RT-PCR, and the pcDNA3.1(+)IIb and pcDNA3.1(+)IIIa were constructed respectively. By sequencing and double digestion, pcDNA3.1(+)IIb and pcDNA3.1(+)IIIa were all correct. Expression of GPIIb and GPIIIa were detected on transfected CHO cells by FCM and RT-PCR. Conclusions (1) Succeeded in constructing pcDNA3.1(+)IIb, pcDNA3.1(+)IIIa. (2) Succeeded in getting the cell lines expressing GPIIb, GPIIIa.     

Synthesis and cellular characterization of novel isoxazolo- and thiazolohydrazinylidene-chroman-2,4-diones on cancer and non-cancer cell growth and death

Coumarins are extensively studied anticoagulants that exert additional effects such as anticancerogenic and even anti-inflammatory. In order to find new drugs with anticancer activities, we report here the synthesis and the structural analysis of new coumarin derivatives which combine the coumarin core and five member heterocycles in hydrazinylidene-chroman-2,4-diones. The derivatives were prepared by derivatization of the appropriate heterocyclic amines which were used as electrophiles to attack the coumarin ring. The structures were characterized by spectroscopic techniques including IR, NMR, 2D-NMR and MS. These derivatives were further characterized especially in terms of a potential cytotoxic and apoptogenic effect in several cancer cell lines including the breast and prostate cancer cell lines MCF-7, MDA-MB-231, PC-3, LNCaP, and the monocytic leukemia cell line U937. Cell viability was determined after 48 h and 72 h of treatment with the novel compounds by MTT assay and the 50% inhibitory concentrations (EC₅₀ values) were determined. Out of the 8 novel compounds screened for reduced cell viability, 4c, 4d and 4e were found to be the most promising and effective ones having EC₅₀ values that were several fold reduced when compared to the reference substance 4-hydroxycoumarin. However, the effects were cancer cell line dependent. The breast cancer MDA-MB-231 cells, the prostate cancer LNCaP cells, and U937 cells were most sensitive, MCF-7 cells were less sensitive, and PC-3 cells were more resistant. Reduced cell viability was accompanied by increased apoptosis as shown by PARP-1 cleavage and reduced activity of the survival protein kinase Akt.In summary, this study has identified three novel coumarin derivatives that in comparison to 4-hydroxycoumarin have a higher efficiency to reduce cancer cell viability and trigger apoptosis and therefore may represent interesting novel drug candidates.     

Maternal and fetal cadmium and selenium status in normotensive and hypertensive pregnancy

Cadmium and selenium concentrations in maternal and umbilical cord blood and amniotic fluid were determined in 37 normotensive and 23 hypertensive women during the last trimester of pregnancy in relation to their smoking status. Thiocyanate concentration in plasma was used as the index of smoking status. Cadmium and selenium were determined with atomic absorption spectrometry (graphite furnace and mercury hydride system). In the group of normotensive and hypertensive women, significantly higher cadmium and lower selenium concentrations in blood in smokers were observed than in nonsmokers. Umbilical cord blood selenium concentrations in both normotensive and hypertensive smokers were significantly lower than in nonsmokers as well. In the group of normotensive women, significant differences in selenium concentrations in amniotic fluid were observed between smokers and nonsmokers. In conclusion, the results of this study show that hypertension in pregnant women smokers is related to significantly higher blood cadmium concentrations, which indicates that cadmium may be considered as an independent factor involved in hypertension.     

Phytophagous British insects and mites and their food-plant families: total numbers and polyphagy

The Phytophagous Insects Data Base (PIDB) was used to summarize information about 6933 species of British insects/mites and their food-plant families. Total species in 183 insect families on 127 vascular plant families were correlated with numbers of plant species in each family in Britain and Europe, accounting for 41.8% of the variation. Families with trees had more insects, while ferns and aquatic, uncommon and ephemeral plants, particularly orchids, had fewer. Seven individual insect families were analysed separately: Aphididae were more closely correlated with plant species numbers than were the more polyphagous Geometridae. Agromyzidae were uncommon on families with trees. Of insect species 75.8% fed on only one plant family and 10.1% were recorded on two families. Species feeding on three families or more were considered to be polyphagous. In the 30 largest insect families, eight had species feeding on only one plant family, while 12 had more than 20% of their species polyphagous. Proportions of family-restricted insects were high on Pinaceae, Gramineae and Compositae, but low on Corylaceae, Primulaceae and Tiliaceae. More pest species were polyphagous. Polyphagy was related to large larvae, larvae overwintering, wood-feeding, ephemeral food sources, poor dispersal abilities and omnivory. Some polyphagous species might be actively evolving in exploitation of vacant niches, leading to later progressive specialization to food-plants.     

Spatial and molecular aspects of estrogen and progesterone receptor expression in human uteri and uterine carcinomas

The expression of steroid hormone receptors as molecules reflecting processes of development and differentiation in the human uterine tissue was analysed in a spatial distinct fashion: tissue samples were excised at the fundus and at different, spatially distinct positions of the uterus. They were analysed for concentrations of cytosolic estrogen and progesterone receptors in supernatants from frozen sections using an isoelectric focusing technique. The spatial and molecular distinct, qualitative and quantitative pattern of their expression in the human uterus and uterine adenocarcinomas were studied by sectioning tissue sample from the functionalis through the basalis of the endometrium until reaching deep myometrial parts of the tissue: (1) Specific spatial patterns of estrogen and progesterone receptor levels were detectable throughout the menstrual cycle. (2) For proliferative endometrium from the functionalis to the basalis of the endometrium, the content of both cytosolic receptor species increased up to 6-fold. (3) Differences detectable were less pronounced in the myometrial part of the tissue. (4) Differences of steroid receptor concentrations measured in the endometrium at different uterine positions were highest between fundus and corpus of the endometrium. (5) Maximal differences were detectable around ovulation. (6) After secretory transformation of the organ, specific patterns were still detectable, however quantitative differences were less pronounced. (7) Additionally, quantitative differences measurable were accompanied by variations of molecular properties of the progesterone receptor as demonstrated in an isoelectric focusing gel. (8) In endometrial adenocarcinomas, not only significant quantitative alterations in steroid receptor content were measured, but also a significantly changed spatial pattern of receptor concentrations, also a change of the molecular properties of the progesterone receptor was resolved if these tumor parameters were compared to those detected in the normal tissue of the same organ surrounding the tumor.     

Rice straw-decomposing fungi and their cellulolytic and xylanolytic enzymes

Filamentous fungi colonizing rice straw were collected from 11 different sites in Korea and were identified based on characterization of their morphology and molecular properties. The fungi were divided into 25 species belonging to 16 genera, including 14 ascomycetes, one zygomycete, and one basidiomycete. Fungal cellulolytic and xylanolytic enzymes were assessed through a two-step process, wherein highly active cellulase- and/or hemicellulaseproducing fungi were selected in a first screening step followed by a second step to isolate the best enzymeproducer. Twenty-five fungal species were first screened for the production of total cellulase (TC), endo-beta-1,4 glucanase (EG), and endo-beta-1,4 xylanase (XYL) using solid-state fermentation with rice straw as substrate. From this screening, six species, namely, Aspergillus niger KUC5183, A. ochraceus KUC5204, A. versicolor KUC5201, Mucor circinelloides KUC6014, Trichoderma harzianum 1 KUC5182, and an unknown basidiomycete species, KUC8721, were selected. These six species were then incubated in liquid Mandels' media containing cellulose, glucose, rice straw, or xylan as the sole carbon source and the activities of six different enzymes were measured. Enzyme production was highly influenced by media conditions and in some cases significantly increased. Through this screening process, Trichoderma harzianum 1 KUC5182 was selected as the best enzyme producer. Rice straw and xylan were good carbon sources for the screening of cellulolytic and xylanolytic enzymes.     

The mycoflora and incidence of aflatoxin,zearalenone and sterigmatocystin in dairy feed and forage samples from Eastern India and Bangladesh

The mycoflora of a range of mixed ruminant feed and forage samples collected in Eastern India and Bangladesh were determined. Most fungi isolated from the samples were those associated with low moisture contents. Several potentially mycotoxigenic fungi and thermotolerant species were present particularly in the rice straw. The most frequently isolated fungi were: Aspergillus versicolor (Vuill.) Tiraboschi, Penicillium citrinum Thorn, Eurotium species, Wallemia sebi (Fr.) v. Arx, Aspergillus penicilloides Speg. and yeasts. Fusarium moniliforme Sheldon and Cladosporium species were prevalent in straw but not other feeds. Levels of certain individual fungi, particularly thermotolerant types, were higher in Bangladesh rice straw although overall counts were similar to those of the Indian samples. Mycotoxin analyses for aflatoxins, zearalenone and sterigmatocystin were carried out. Aflatoxins were detected in significant amounts in some feed samples from Eastern India but not in rice straw from India and Bangladesh. Zearalenone occurred in a Paspalum straw sample and three other feed samples from India and sterigmatocystin was detected in three rice straw samples from Bangladesh.     

Estrus synchronization and pregnancy rates in cyclic and noncyclic beef cows and heifers treated with syncro-mate B or Norgestomet and Alfaprostol

Postpartum lactating cows (N=118) and virgin heifers (N=60) were treated with subcutaneous Norgestomet implants for nine days and received either an intramuscular injection (im) of 5 mg estradiol valerate and 3 mg Norgestomet at the time of implant insertion or an im injection of 5 mg Alfaprostol 24 hr before implant removal. Animals were artificially inseminated 12 hr after detection of estrus. Of the cows and heifers, 78% and 88%, respectively, were in estrus within five days after implant removal (P<0.09). There was no difference between treatments in the proportion of animals in estrus or in the timing of estrus (P<0.85). Estrus was detected in a greater (P<0.05) proportion of animals that were cyclic prior to treatment (88%) than among those that were anestrous prior to treatment (77%). Pregnancy rates after five days were similar between heifers that were cyclic (42%) or anestrous (47%) prior to treatment; however, the five-day pregnancy rate in cows that were anestrous prior to treatment was 38% lower than that in cows that were cyclic prior to treatment (17 vs 55%, P<0.01). Although the treatments synchronized or induced estrus in both cyclic and anestrous animals, marked variability in estrous response and fertility among previously cyclic or anestrous postpartum cows limited the effectiveness of the treatments.     

The influence of blinding, olfactory bulbectomy and pinealectomy on plasma and anterior pituitary prolactin levels and on uterine and anterior pituitary weights in normal and neonatally androgenized rats

Lactating Sprague-Dawley rats had their litters adjusted to 8-10 pups on day 3 of lactation favoring females and some litters were injected with 1.25 mg of testosterone propionate to neonatally androgenize (NA) them. At 22-25 days of age both normal and NA animals were ovariectomized (OVX) and subjected to either sham olfactory bulbectomy (ANOS) + sham pinealectomy (PX), blinding (BLD) + ANOS or BLD + ANOS + pinealectomy (PX). At 13 weeks of age all animals were injected with 0.5 mg of polyestradiol phosphate. At 15 weeks of age the animals were fitted with atrial catheters and at 16 weeks of age blood samples (0.3 ml) were obtained every 3 hours over a 24 hour period. Uterine and anterior pituitary (AP) weights were recorded at sacrifice. Plasma and AP were assayed for prolactin (PRL) by RIA and AP were also assayed for PRL using the Nb2 lymphoma cell PRL bioassay. In both normal and NA animals, BLD + ANOS suppressed plasma PRL levels and PX partially prevented this response. Uterine weights were similar among groups while AP weights were significantly lower for sensory deprived animals. Anterior pituitaries extracted at pH 7.6 had a PRL concentration that was higher for the BLD + ANOS groups when estimated by either RIA or BA, a result that was not observed when the AP were extracted at pH 10.6. The amount of PRL extracted at pH 10.6 was twice that obtained at pH 7.6. Sensory deprived animals that were OVX prepubertally and administered estrogen as adults had a small but significant increase in mean plasma prolactin at 1700 hr. Both normal and NA animals responded in a similar manner to experimental manipulation.     

Ecology of dermatophytes and other keratinophilic fungi in swimming pools and polluted and unpolluted streams

The biodiversity and richness of keratinophilic fungal communities including dermatophytes were assessed in three stream sites and three swimming pools in the Nablus district in Palestine, using hair baiting (HBT) and surface dilution plate (SDP) techniques, over 8- and 6-month periods, respectively. The effect of wastewater effluent and selected ecological factors on these fungi in relation to species diversity and population densities were also considered. Fifty keratinophilic fungal species were recovered from the aquatic habitats studied, of which 42 were recovered from stream sites and 22 from swimming pools. Of these fungi 6 were either dermatophytes (Microsporum gypseum, and Trichophyton mentagrophytes) or dermatophyte related species (Chrysosporium merdarium, Ch. tropicum, Ch. keratinophilum and T. terrestre). The most frequently isolated species in the three pools were Acremonium strictum and Cladosporium cladosporioides, using Sabouraud dextrose agar medium (SDA). The most abundant species were Acr. strictum, and Aspergillus flavus. However, only 4 species were isolated using the SDA medium amended with 5-flurocytosine (5-FC). The most frequent and abundant species in the three stream sites using SDA medium were Geotricum candidum, and Penicillium chrysogenum. The most frequent species in the three sites using the 5-FC medium, was Paecilomyces lilacinus. Using HBT, the most abundant and frequent species in the three stream sites were G. candidum, and Pa. lilacinus, on SDA medium, and Pa. lilacinus, and Gliocladium nigrovirens on the 5-FC medium. The 5-FC medium was more suitable for the isolation of dermatophytes and closely related species than the SDA medium; 6 were recovered on 5-FC, whereas only one on the SDA medium. Variation in the levels of keratinophilic fungal populations from the three stream sites sampled 5 times over an 8-month period, followed comparable fluctuation patterns. Wastewater affected fungal population densities with the highest levels in the un-polluted stream sites, and lowest in the heavily polluted sites. Swimming pools, polluted and un-polluted stream sites were found to be rich in pathogenic and potentially pathogenic fungi.     

Androgen and Corticoid Levels in Blood and Body Extracts of High- and Low-ranking Swordtail Males (Xiphophorus helleri) before and after Social Isolation

The two highest- and the two lowest-ranking swordtail males were determined by the criterion of number of attacks directed at and received from every other male in their breeding tanks. The events were recorded until 50 bites were given (high-ranking males) or received (low-ranking males). 40 high- and 40 low-ranking males were bled either after being socially isolates for 4 weeks or after reaching the target number. Androgen and corticoid concentrations both in their blood and their body extracts were measured by means of radioimmunoassay. Although the agonistic behaviour patterns and social experience of high- and low-ranking males were totally different, the baseline hormonal states of the animals were indistinguishable both in body extracts and blood. Isolation led to decreased blood androgen and corticoid levels in high- and low-ranking males. In the body extracts, only the corticoids were reduced. A significant correlation between blood and tissue concentrations was found only in the case of corticoids. I would suggest that the contradictory findings in the literature dealing with the relationship between hormones and dominance result from differences in experimental procedure.     

The Occurrence and Survival of Coliforms and Salmonellas in Apple Juice and Cider

Apples and juices from large and small cidermakers were examined for the presence of coliform organisms and salmonellas. Coliforms were found both on the fruit and in the juice, and salmonellas were isolated on more than one occasion from the flume water. Experiments showed that salmonellas could survive in apple juice for 30 d at a pH of 3·6.     

The Identification and Purification of Pyronin and Rhodamine Dyes

The purity of 27 commercial pyronin and rhodamine samples was studied by thin-layer chromatography and visible spectroscopy. Seven different red dyes were detected and separated. The chemical identities of 6 of these were established by nuclear magnetic resonance spectroscopy. The identities of samples sold as rhodamine B and rhodamine 6G were as labelled 8 out of 9 times, the pyronin (G)Y samples were as labelled 5 out of 8 times and the 10 samples sold as acridine red, pyronin B, rhodamine 36 and rhodamine S were always incorrectly labelled. The dextrin and salt contents of the dyes were determined by solvent extraction of the dye with dry methanol or ethanol. Amounts of dextrin and salt varied from none to nearly 90%. Practical methods for identification, separation of coloured components and removal of dextrin and salt are given.     

Purification and properties of soluble and bound gamma-glutamyltransferases from radish cotyledon

Soluble and cell wall bound gamma-glutamyltransferases (GGTs) were purified from radish (Raphanus sativus L.) cotyledons. Soluble GGTs (GGT I and II) had the same M(r) of 63,000, and were composed of a heavy subunit (M(r), 42,000) and a light one (M(r), 21,000). The properties of GGT I and II were similar. Bound GGTs (GGT A and B) were purified to homogeneity from the pellet after the extraction of soluble GGTs. GGT A and B were monomeric proteins with an M(r) of 61,000. The properties of GGT A and B were similar. Thus, bound GGTs were distinguished from soluble GGTs. The optimal pHs of soluble and bound GGTs were about 7.5. Both soluble and bound GGTs utilized glutathione, gamma-L-glutamyl-p-nitroanilide, oxidized glutathione and the conjugate of glutathione with monobromobimane as substrates, and were inhibited by acivicin, but soluble GGTs were also distinguished from bound GGTs with regard to these properties.     

F-specific RNA bacteriophages and sensitive host strains in faeces and wastewater of human and animal origin

Faeces of humans, pigs, cattle and chickens were investigated for the presence of somatic coliphages, F-specific bacteriophages and Escherichia coli strains sensitive to infection by F-specific phages. Attention was given to the possible effect of age and use of antibiotics on the prevalence of the FRNA phages and sensitive E . coli strains. Somatic coliphages were often detected in high numbers in all types of faeces. In contrast, FRNA phages were rarely detected in faeces from humans and cattle but more often in faeces from pigs and adult chickens. Samples from young chickens (with or without antibiotics) were consistently positive for FRNA phages (up to 3 × 10⁶ pfu/g). F-specific RNA phages were found in substantial numbers (> 10³ pfu/ml) in a variety of wastewaters: domestic, hospital, slaughterhouses and occasionally in 'grey water'. Their origin in wastewater was not clear. Strains from faeces usually belonged to serogroups I and IV. These types were also found in wastewater, as were group II and III strains. Serogroup II phages were abundant in wastewater of human origin but rare in faeces. Escherichia coli strains sensitive to infection by F-specific phages were common in faeces (overall 290/1081: 27%). No strains with fully derepressed F-pilus synthesis were detected among the sensitive strains. It is concluded that the occurrence of F-specific RNA bacteriophages in water points to sewage pollution rather than faecal pollution; the mechanism of replication of these organisms in wastewater is not understood.     

Lipid peroxidation and antioxidants in hyperlipidemia and hypertension

Lipid peroxidation and lipid-derived oxidized products have been implicated in the pathogenesis of a variety of human diseases. To clarify the role of oxidative stress in essential hypertension and hypercholesterolemia the in vitro oxidative susceptibility of LDL, the antioxidant status and the lipid peroxide content of blood plasma were examined in hypercholesterolemic (HC), hypertensive (H), hypercholesterolemic/hypertensive (HH) and normolipidemic/normotensive subjects (N). Plasma ascorbate and lipid-soluble antioxidants were lower, while LDL oxidizability, CE-OOH and TL-OOH were higher in H, HC, and HH groups than in the N group. No difference was observed among groups for PL-OOH and isoprostanes. In summary, the results show that: 1) lipid- and water-soluble antioxidants are lower in hypercholesterolemic and hypertensive patients as compared to normal subjects, whereas the lipid peroxide content and the LDL susceptibility to oxidation were higher; 2) total cholesterol, LDL-cholesterol, apoB and CE-OOH were negatively correlated with the content of a-tocopherol; 3) there was a positive correlation between the content of lipid-soluble antioxidants and the resistance of LDL to oxidation; and 4) CE-OOH and TL-OOH were positively correlated with total cholesterol and LDL-cholesterol.