Seasonal variation and estradiol-dependent elevation of Thames estuary eel Anguilla anguilla plasma vitellogenin levels and comparisons with other United Kingdom estuaries

Eel Anguilla anguilla plasma vitellogenin was investigated as a biomarker of exposure to environmental compounds with estrogenic activity, along the tidal course of the Thames Estuary, UK. A. anguilla was chosen as a sentinel species because of their wide distribution, robustness in field and laboratory studies and also because they have a characterised normal intersex' condition where the gonad contains both developing male and female gonadal cells termed a Syrski organ. Following laboratory exposure to 17beta-estradiol (intraperitoneal injection), a plasma protein (approx. 211 kDa apparent molecular weight) was detected by monoclonal antibodies to vitellogenin of striped bass (Morone saxatilis). Western and dot blot analyses were developed and vitellogenin was isolated from 17beta-estradiol-treated fish to calibrate the quantification of the blots by image analysis. The limits of sensitivity for the Western and dot blots were 100 and 10 ng vitellogenin/ml, respectively. Levels of vitellogenin in Thames estuary samples were below the detection limits of the Western but not the dot blot, and showed no statistically significant site-specific (10 sites) and seasonal-specific (May, August, November) differences. Values were observed to be low, between 11 and 165 ng/ml, compared with 17-50 mg/ml for 17beta-estradiol-treated eels. Similar low levels of plasma vitellogenin were determined in fish sampled along the Tyne, Wear, Tees or Humber estuaries, or the Weston canal Liverpool, with mean plasma vitellogenin levels varying between 44 and 82 ng/ml. These levels of vitellogenin in A. anguilla plasma were observed to be consistent with the known biology of the eel. Immature females, or fish with syrski organs, reported both lower levels and smaller variation of plasma vitellogenin concentrations whereas the highest plasma vitellogenin concentrations were determined in fish above 45 cm consistent with female fish. These results indicate inter-species variation between the plasma vitellogenin concentrations of A. anguilla and other published fish studies undertaken along the same estuaries.

Effects of clozapine, olanzapine, risperidone, and haloperidol on hostility among patients with schizophrenia

OBJECTIVE

This study compared the specific antiaggressive effects of clozapine with those of olanzapine, risperidone, and haloperidol.

METHODS

A total of 157 inpatients with schizophrenia or schizoaffective disorder and a history of suboptimal treatment response were randomly assigned to receive clozapine, olanzapine, risperidone, or haloperidol in a double-blind 14-week trial. The trial was divided into two periods: eight weeks during which the dosage was escalated and then fixed, and six weeks during which variable dosages were used. The hostility item of the Positive and Negative Syndrome Scale (PANSS) was the principal outcome measure. Covariates included the items that reflect positive symptoms of schizophrenia (delusions, suspiciousness or feelings of persecution, grandiosity, unusual thought content, conceptual disorganization, and hallucinations) and the sedation item of the Nurses Observation Scale for Inpatient Evaluation (NOSIE).

RESULTS

Patients differed in their treatment response as measured by the hostility item of the PANSS. The scores of patients taking clozapine indicated significantly greater improvement than those of patients taking haloperidol or risperidone. The effect on hostility appeared to be independent of the antipsychotic effect of clozapine on other PANSS items that reflect delusional thinking, a formal thought disorder, or hallucinations and independent of sedation as measured by the NOSIE. Neither risperidone nor olanzapine showed superiority to haloperidol.

CONCLUSION

Clozapine has a relative advantage over other antipsychotics as a specific antihostility agent.

Analysis of estrogens in river water and effluents using solid-phase extraction and gas chromatography-negative chemical ionisation mass spectrometry of the pentafluorobenzoyl derivatives

A procedure was developed for the analysis of estrogens in environmental water and effluents. Samples were extracted by passing through polymer-impregnated solid-phase extraction discs or C18 cartridges, followed by gas chromatography-negative chemical ionisation mass spectrometry of the pentafluorobenzoyl derivatives. The derivatives were stable and gave diagnostic negative molecular ions as the base peak for each of the major estrogens studied. The absolute recovery of estrogens spiked into clean groundwater using the disc procedure was 84-116% at the 10 ng l(-1) level (calculation not based on use of internal standards). Using doubly deuterated estradiol as internal standard added prior to extraction, the % relative standard deviation of estrogen extraction and analysis in spiked groundwater at the 10 ng(-1) level was 2.6-9.8%. Detection limits were 0.2 ng l(-1) or below for the major estrogens, based on a 2.5 litre sample. The most abundant estrogen was estrone, with concentrations over the range 6.4-29 ng l(-1) in effluents, and 0.2 to 17 ng l(-1) in water from the River Thames.

Replacement of fish oil with rapeseed oil in diets of Atlantic salmon (Salmo salar) affects tissue lipid compositions and hepatocyte fatty acid metabolism

Duplicate groups of Atlantic salmon post-smolts were fed five practical-type diets in which the added lipid was 100% fish oil [FO; 0% rapeseed oil (0% RO)], 90% FO + 10% RO (10% RO), 75% FO + 25% RO (25% RO), 50% FO + 50% RO (50% RO) or 100% RO, for a period of 17 wk. There were no effects of diet on growth rate or feed conversion nor were any histopathological lesions found in liver, heart, muscle or kidney. The greatest accumulation of muscle lipid was in fish fed 0% RO, which corresponded to significantly lower muscle protein in this group. The highest lipid levels in liver were found in fish fed 100% RO. Fatty acid compositions of muscle lipid correlated with RO inclusion in that the proportions of 18:1(n-9), 18:2(n-6) and 18:3(n-3) all increased with increasing dietary RO (r = 0.98-1.00, P < 0.013). The concentrations of eicosapentaenoic acid [20:5(n-3)] and docosahexaenoic acid [22:6(n-3)] in muscle lipid were significantly reduced (P < 0.05), along with total saturated fatty acids, with increasing dietary RO. Diet-induced changes in liver fatty acid compositions were broadly similar to those in muscle. Hepatic fatty acid desaturation and elongation activities, measured using [1-(14)C] 18:3(n-3), were increased with increasing dietary RO. Limited supplies of marine fish oils require that substitutes be found if growth in aquaculture is to be maintained such that fish health and product quality are not compromised. Thus, RO can be used successfully as a substitute for fish oil in the culture of Atlantic salmon in sea water although at levels of RO >50% of dietary lipid, substantial reductions occur in muscle 20:5(n-3), 22:6(n-3) and the (n-3)/(n-6) polyunsaturated fatty acid (PUFA) ratio, which will result in reduced availability of the (n-3) highly unsaturated fatty acids that are beneficial for human health.

Seasonal export of phosphorus from a lowland catchment: upper River Cherwell in Oxfordshire, England

The export of phosphorus from a lowland catchment, the River Cherwell in southern England, was measured over a period of 1 year. The results describe total phosphorus concentrations in the water and river discharge at 4-day intervals. These were used to estimate the load of total phosphorus exported from the catchment. These annual loads were compared with exports estimated from sewage inputs and diffuse inputs calculated from land-coverage data, with assigned phosphorus export coefficients for particular land uses. The method was further developed to examine seasonal changes in phosphorus exports by predicting monthly losses using annual export coefficients normalised with respect to the relative hydraulic runoff for a particular month. The results show a strong seasonal dependence of total exports, with retention of phosphorus in the river system in the spring to early autumn and release of stored material during the winter. This pattern remained true, even with 50% increase in the main land-cover export and a similar increase in treated sewage exports.

Investigations of the origins of estrogenic A-ring aromatic steroids in UK sewage treatment works effluents

The present preliminary study describes an investigation of a putative aromatisation pathway in sewage from cholesterol through the corresponding A-ring aromatic steroid, norcholest-1,3,5(10)-trienol (NCT) to estrone. The synthesis and analytical characterisation of NCT and of the trimethyl silyl ether by gas chromatography-mass spectrometry, is described. The analytical properties of synthetic NCT were used to direct a search for the compound over several months in 1998 in the effluents of two sewage treatment works (STW; Deephams and Harpenden, north London). The study was prompted by the earlier findings that increased vitellogenin concentrations in the plasma of caged male rainbow trout held in the STW effluents (so-called fish 'feminisation') could be attributed to the presence of A-ring steroids such as estrone. Until now it has been assumed that these steroids originate from the STW influents and it is not clear to what extent, if at all, aromatisation of steroids might occur during STW operation. NCT was only detected in the solid particles associated with the effluents on one occasion in 8 months. This suggests that the hypothesised pathway is not a major one. Confirmation of previous reports of estrone and 17 beta-estradiol was also obtained using a published analytical method and by a simple modification of the method these reports were extended to include a regular occurrence of the weaker estrogen, 16 alpha-estriol in the case of Harpenden STW effluents in 1998.

Postpositivist interpretations of the chemical revolution

Expressing the growing interest of historians of science in “the history of science as history,” this study offers a critical account of recent developments in the historiography of the Chemical Revolution. It explores the philosophical and historiographical dimensions of the “postpositivist” (or “theoreticist”) interpretations of the Chemical Revolution, which displaced the positivist-whig historiographical hegemony in the 1960s and 1970s, only to be challenged by the sociology of knowledge in the 1980s and 1990s. Despite its brief ascendancy in the pantheon of interpretive styles, postpositivism had a profound influence on the historiography of the Chemical Revolution, and this study will enable us to better appreciate its complex, variegated, and important results. Besides providing future specialists in the field with useful information, this study is designed to solicit the interest and input of more general historians in the history of science.

Depletion of alpha-tocopherol and astaxanthin in Atlantic salmon (Salmo salar) affects autoxidative defense and fatty acid metabolism

Duplicate groups of Atlantic salmon post-smolts were fed four purified diets supplemented with both vitamin E and the carotenoid astaxanthin (Ax) (+E, +Ax), or supplemented with either vitamin E or Ax (-E, +Ax and +E, -Ax) or deficient in both vitamin E and Ax (-E, -Ax) for 22 wk. There were no effects of diet on growth rate, but an extensive lipoid liver degenerative lesion was observed in 15% of fish fed diets deficient in vitamin E. Tissue vitamin E concentrations varied in accordance with dietary vitamin E in liver, muscle, heart, plasma, brain and eye; levels were reduced to approximately 3% in liver but only to 40% in eye of fish fed diets deficient in vitamin E compared with those fed diets supplemented with vitamin E. An interactive sparing of Ax supplementation on tissue vitamin E concentration was observed, but only in brain. Dietary deficiency of both vitamin E and Ax significantly increased the recovery of desaturated and elongated products of both [1-(14)C] 18:3(n-3) and [1-(14)C] 20:5(n-3) in isolated hepatocytes, suggesting that conversion of fatty acids to their long-chain highly unsaturated products can be stimulated by a deficiency of lipid-soluble antioxidants. The antioxidant synergism of vitamin E and Ax was supported by their ability to reduce malondialdehyde formation in an in vitro stimulation of microsomal lipid peroxidation and to reduce plasma levels of 8-isoprostane. The results of this study suggest that both vitamin E and the carotenoid Ax have antioxidant functions in Atlantic salmon.

Development of hepatic CYP1A and blood vitellogenin in eel (Anguilla anguilla) for use as biomarkers in the Thames Estuary, UK

The potential of eel (Anguilla anguilla) as a monitoring species for the Thames Estuary, UK, was examined. Hepatic cytochrome P4501A [7-ethoxyresorufin O-deethylase (EROD) activity] and blood vitellogenin (Western analysis) were investigated as biomarkers of exposure to, respectively, organic contaminants and to contaminants showing estrogenic activity. Hepatic microsomal EROD activities in A. anguilla from seven sites in the Thames Estuary in May 1998 varied three-fold (111 +/- 24 to 355 +/- 42 pmol min-1 mg protein-1) (mean +/- S.E.M.) and showed correlation with salinity; however, the latter relationship was not maintained at other times of the year. The range of EROD activities was two- to eight-fold higher than the 37 +/- 8 pmol min-1 mg-1 for A. anguilla from the relatively clean Tamar Estuary. beta-Naphthoflavone treatment (5 mg kg-1 wet wt.; 2 days) of Thames A. anguilla produced a two-fold increase in hepatic microsomal EROD activity. Comparing the Thames EROD data with those for A. anguilla from well-characterised contaminated sites in the Netherlands (Van der Oost, R., Goksøyr, A., Celander, M., Heida, H., & Vermeulen, N. P. E. 1996. Aquatic Toxicology, 36, 189-222), the Thames is suggested to be moderately impacted by polycyclic aromatic hydrocarbons and related contaminants. 17-beta-Estradiol treatment produced the appearance of a plasma protein of 211 Kd app. mol. wt. (recognised by antibodies to vitellogenin of Morone saxatilis), but putative vitellogenin could not be detected in A. anguilla from selected sites in the Thames Estuary.

Development of a fish in vitro cell culture model to investigate oxidative stress and its modulation by dietary vitamin E

When cultured in Dulbecco's minimal essential medium the established epithelioma papulosum cyprini cell line from carp was found to be vitamin E-deficient due to the very low level of vitamin E in the medium and the foetal calf serum used as supplement. The toxicity of oxidative stressors to this cell line was evaluated by means of the neutral red cytotoxicity assay and it was found that an organic hydroperoxide, t-butylhydroperoxide was extremely cytotoxic and that the redox-cycling agents diquat and menadione were less toxic. When grown under vitamin E supplementation (25 microM), the toxicity of these chemicals was reduced by at least an order of magnitude in concentration demonstrating the protective effect of vitamin E. These data show the importance of vitamin E status for interpretation of in vitro and in vivo data and that this in vitro system is useful for mechanistic studies.

Flesh Lipid and Carotenoid Composition of Scottish Farmed Atlantic Salmon (Salmo salar)

Samples of steaks from market-size salmon (2.5-5 kg), produced under the requirements of the Product Certification Scheme for Scottish Quality Farmed Salmon, were obtained from five Scottish salmon producers on a weekly basis for over 2 years. Samples were assayed for total lipid content, lipid class composition, fatty acid composition, vitamin E content, and carotenoid pigment [astaxanthin (AX) and canthaxanthin (CX)] content. In addition, samples were obtained from the same producers to assess loss of carotenoid pigment in the period up to 120 h post-harvest and to measure lipid and pigment content of different body regions. The analyses showed a positive correlation between dietary lipid and deposition of lipid in flesh, although there was great variation in flesh lipid content within each dietary lipid level. The average lipid content of Scottish salmon was 10.1 +/- 2.9% (n = 495). Salmon flesh was rich in the n-3 highly unsaturated fatty acids, 22:6n-3 and 20:5n-3, with average values of 11.3 and 5.4% of total fatty acids or 10.2 and 4.8 g/kg flesh, respectively. Vitamin E content of salmon flesh was around 30 mg/kg but was significantly higher in fish fed the lowest dietary lipid level. Studies investigating changes in carotenoid pigmentation up to 120 h post-harvest suggested that fish fed AX alone showed a loss of pigment over time that did not occur in fish fed either CX alone or a combination of AX and CX. Measurement of lipid content of different body regions showed that the highest levels were found in the region immediately in front of the dorsal fin and that the lowest lipid levels were in the tail region. Total lipid content of all five body zones was positively correlated with dietary lipid. Carotenoid pigment levels were the same across all body zones and were not affected by dietary lipid.

The second finger of Urbs1 is required for iron-mediated repression of sid1 in Ustilago maydis

The urbs1 gene encodes a transcriptional regulator of siderophore biosynthesis in Ustilago maydis. Biological and DNA-binding activities of the two putative zinc-finger motifs of Urbs1 were studied by analyzing mutants containing altered finger domains. The mutated urbs1 alleles from three previously described N'-methyl-N'-nitro-N-nitrosoguanidine (NTG) mutants were mapped and cloned by a gap-repair procedure. Sequence analyses revealed single amino acid substitutions in two of the NTG mutants. Both mutations (G-507 to D in urbs1-1 and P-491 to L in urbs1-3), which are located in the Urbs1 C-terminal finger domain, reduced DNA-binding activity by 10-fold and were sufficient to confer a urbs1-minus phenotype. The third NTG urbs1 mutant (urbs1-2) also contained a mutation in one of the conserved amino acids (P-518 to S) in the C-terminal finger domain, but this mutation alone was not sufficient to confer a urbs1-minus phenotype. A second frame shift mutation was identified in urbs1-2 and is necessary for the urbs1-minus phenotype. In an analysis of the function of the N-terminal finger of Urbs1, the conserved amino acid Arg-350 was mutated to leucine. A Urbs1 protein with this mutation complemented a urbs1 null mutant strain. By contrast, a similar mutation in the C-terminal domain abolished the ability of Urbs1 to regulate siderophore biosynthesis and greatly reduced its ability to bind target DNA.

Nicotine-haloperidol interactions and cognitive performance in schizophrenics

Nearly 90% of schizophrenics smoke cigarettes, considerably higher than the general population's rate of 25%. There is some indication that schizophrenics may smoke as a form of self-medication. Nicotine has a variety of pharmacologic effects that may both counteract some of the cognitive deficits of schizophrenia and counteract some of the adverse side effects of antipsychotic drugs. In the current study, we assessed the interactions of haloperidol and nicotine on cognitive performance of a group of schizophrenics. These patients were in a double-blind study, randomly assigning them to low, moderate, and high dose levels of haloperidol. The subjects, all smokers, came to the laboratory on four different mornings after overnight deprivation from cigarettes. In a double-blind fashion, they were administered placebo, low (7 mg/day), medium (14 mg/day), or high (21 mg/day) dose nicotine skin patches. Three hours after administration of the skin patch, the subjects were given a computerized cognitive test battery including: simple reaction time, complex reaction time (spatial rotation), delayed matching to sample, the Sternberg memory test, and the Conners continuous performance test (CPT). With the placebo nicotine patch, there was a haloperidol dose-related impairment in delayed matching to sample choice accuracy and an increase in response time on the complex reaction time task. Nicotine caused a dose-related reversal of the haloperidol-induced impairments in memory performance and complex reaction time. In the CPT, nicotine reduced the variability in response that is associated with attentional deficit. These results demonstrate the effects of nicotine in reversing some of the adverse side effects of haloperidol and improving cognitive performance in schizophrenia.

Sequences and proteins required for iron-regulated expression ofsid1ofUstilago maydis

The molecular biology of the high affinity, siderophore-mediated iron uptake system of the basidiomycete fungus Ustilago maydis is under investigation. Ustilago maydis produces two cyclic peptide siderophores, ferrichrome and ferrichrome A. Biosynthesis of both siderophores is initiated by ornithine-N5-oxygenase, the product of sid1. sid1 mRNA accumulates only during growth under iron starvation conditions in wild-type cells or constitutively in urbs1 mutants, urbs1 encodes a 100-kDa protein with putative Zn finger domains that share sequence identity with those of the GATA family of transcription factors. The promoter region of sid1 was defined by deletion analysis of a 3.0-kb region 5′ to the translational start of sid1 using the Escherichia coli GUS gene as a reporter. Three regions were defined by this analysis to be critical to expression of sid1. These include (i) a 306-bp region containing two GATA sequences and mapping 2.4 kb from the start of translation; (ii) a 439-bp region immediately 5′ to the start of transcription; and (iii) a region encompassing the first intron of sid1. Deletion of the GATA sequences resulted in deregulated expression of sid1, while elimination of the latter two sequences ablated expression of the gene under all circumstances. Current efforts are focused on determining whether Urbsl interacts directly with the sid1 promoter via the GATA sequences and whether this interaction is dependent upon iron. Key words: GATA, transcription factor, siderophore, ferrichrome, iron, Urbs1.

Bioaccumulation of the lipophilic metabolites of nonionic surfactants in freshwater organisms

Nonylphenol (NP), nonlyphenol monoethoxylate (NP1EO) and nonylphenol diethoxylate (NP2EO) were determined in different freshwater organisms from the surface waters in the Glatt Valley, Switzerland. Rather high concentrations of the compounds investigated have been found to occur in macrophytic algae, particularly Cladophora glomerata (up to 38 mg kg(-1), 80 mg kg(-1), and 28 mg kg(-1) of NP, NP1EO and NP2EO, respectively), the bioconcentration factors of NP reaching up to 10,000. The concentrations in fish were much lower (NP: < 0.03-1.6 mg kg(-1), NP1EO: 0.06-7.0 mg kg(-1), and NP2EO: <0.03-3.1 mg kg(-1) indicating that biomagnification did not take place. Similar concentrations to those in the fish were determined in different tissues of a wild duck. The estimated bioconcentration factors in fish tissues ranged from 13 to 410 for NP, 3 to 300 for NP1EO and 3 to 330 for NP2EO.

Feeding ecology of green catbirds (Ailuroedus crassirostris) in subtropical rainforests of south-eastern Queensland

Foraging data for green catbirds were collected over an 8-year period in lowland (dry) and upland (wet) subtropical rainforests of the Jimna and Conondale Ranges. The fruits of 104 species of trees, palms and vines comprised the bulk of the diet. Catbirds foraged the fruits of a similar number of species (56) in lowland forest as in upland forest (60). Lowland forest was distinctive, however, in that almost 77% of the food plants occurring in upland forest were rare or absent in lowland forest. Catbirds also foraged flowers, various plant material, insects and millipedes, and these were also significant components of the diet during spring and summer. Different species of asynchronous fruiting figs (Ficus spp.) occurred in lowland and upland forest, and these were the most important foods in each forest type. In lowland forest, catbirds seldom ventured beyond their home ranges (average size 1.9+/-O.2 ha) to forage, and bred from December to March when figs were the only reliable fruit that figured prominently in the diet. Insects also appeared to be an important (perhaps essential) component of the nestling diet during this period. Long-term (5-10 years) data on the fruiting phenology of 94 of the food plants enabled the relationship between the fruiting reliability of food plants and their importance in the diet to be evaluated. Availability of most (79% in lowland forest, 77% in upland forest) species of fruit was irregular and foraging by catbirds was therefore mostly opportunistic.

Vasectomy and nonfatal myocardial infarction: continued observation indicates no elevation of risk

The incidence of nonfatal myocardial infarction among 4,733 vasectomized men followed for 33,969 man-years was 1.3 cases per 1,000 man-years. This incidence was nearly identical in a 5-fold larger series of comparable nonvasectomized men. These data represent a substantially increased long-term followup over that reported previously for these groups and provide continued assurance of the lack of an association between vasectomy and myocardial infarction, particularly 10 or more years after vasectomy.

Play activities of mentally handicapped children at home and mothers' perception of play

Reviewers have frequently commented on the meagre literature that is available on the play of mentally handicapped children, especially play at home. This study involved 67 families with a moderately or severely handicapped child aged mainly between 2 and 12 years, living in Dublin city. Details were obtained on who the children played with; the activities they engaged in and aspects of the home environment conducive to play. Furthermore mothers' perception of play are reported along with their reactions to playing with their child. It was found that the children's play was immotive and lacking in variety and that it invariably occurred within the family. Mothers viewed play as very important and saw it as an enjoyable and beneficial experience for themselves as well as the child. It is argued that parents should be given opportunities to learn how best they could nurture their child's development through play.

One hundred kidney transplants in the Belfast city hospital

100 kidney transplants have been carried out on 91 patients (7 had 2 transplants and 2 had 3 transplants). 4 transplants were from living related donors and 96 from cadavers. 76 patients survive, all but one with functioning kidneys. The cumulative survival of patients was 82% at 2 years and 80-7% at 5 years. 8 patients died with functioning grafts, and 2 of the other deaths took place more than 3 months after removal of a rejected kidney and resumption of haemodialysis. There were no deaths from sepsis in the first 60 days after transplantation. The cumulative survival of all grafts was 82-1% at 2 and 5 years. The cumulative survival of first grafts was 82-5% at 2 and 5 years.

Renal failure after radiological contrast media

Over a 12-month period four patients developed acute renal failure after undergoing radiological investigations using contrast media. Though the incidence of serious complications is low, the possibility of adverse side effects must be weighed against the usefulness of the information provided by these techniques.