A new genus of Syllidae (Polychaeta) from Western Australia

During a study carried out on the subfamily Exogoninae (Syllidae) from Australia, several specimens of a new genus and species were found in samples of dead coral substrate from Western Australia. They have long palps, fused except for a terminal notch, long median and two short lateral antennae, a single pair of short tentacular cirri, and short dorsal cirri, somewhat longer than the parapodial lobes. These characters resemble those of the genus Exogone Örsted, 1845. However, all these appendages are articulated. The chaetae are very similar to those of several species of Syllis Lamarck, 1818, having coarse spines on the margin of compound chaetal blades and truncated dorsal simple chaetae. Furthermore, the pharynx begins in chaetiger 3, posterior to the peristomium, as in many species of the genus Syllis; this condition does not occur in any described species of Exogone. The new genus is provisionally proposed to belong to the subfamily Syllinae, although it has some characters typical of the Exogoninae. Examination under the SEM shows another peculiar feature, the nuchal organs are distinctly laterally located. Within the Syllinae, only Paratyposyllis Hartmann-Schröder, 1962 has a single pair of tentacular cirri, but in that genus, the palps are only basally fused.     

Effect of the presence and location of corpus luteum on competence of bovine cumulus-oocyte complexes

This study aimed to determine the effect of presence of the corpus luteum (CL) and its influence on cumulus–oocyte complexes (COCs) obtained from the ipsilateral or contralateral ovary in bovine on the recovery and capacity of the oocytes to sustain mono-spermic fertilization, undergo preimplantation development, and develop to the blastocyst stage. Ovaries were collected at a local slaughterhouse and kept in pairs corresponding to the same animal. In the first experiment the variables evaluated were compared between cows with (CCL⁺) and without (CCL^-) CL, and for the second experiment, comparisons were made between ovaries with an ipsilateral (CL⁺), contralateral (CL⁻), and no (NCL). The recovery rate of COCs was higher in ovaries from CCL⁻ cows, and a higher proportion of grade 1 COCs were recovered from this group. A higher proportion of metaphase I oocytes at 7 h of maturation, and a higher rate of cleavage were observed in the CCL⁺ group; however, a higher proportion of embryos were obtained from the CCL⁻ group. Besides, COCs from the CL⁺ group had a lower proportion of grades 1 and 2 morphological qualities, lower rate of metaphase II oocytes at 22 h of maturation, and lower rate of formation of two pronuclei, whereas a higher proportion of unfertilized oocytes after in vitro fertilization. On the other hand, the COCs from the CL⁻ group displayed a lower proportion of oocytes with more than two pronuclei, higher cleavage rate, and higher final blastocyst production were obtained when compared to CL+. Thus, the effects of CL on the competence of bovine COCs are different depending on the anatomical proximity of their location in the animal, negatively affecting the quality of COCs located in the same ovary, but not having negative effects on the competence of COCs in the ovaries contralateral to their location.     

Hydrolysis of adenylyl(2'-5')adenosine in chick embryo sera

Similar to adult chick sera in chick embryo sera the enzyme activity hydrolyzing the core of the dimer of A-5A - adenylyl(2' -5')adenosine is present. The enzyme activity possesses the same properties in both sera. Heating of the serum to 60 degrees C for 30 minutes does not affect the enzyme activity. A marked decrease in activity occurs after heating of the serum to above 65 degrees C. Hydrolysis of A2' p5' A in the serum is more efficient under alkaline conditions (pH 9-10) than at physiological pH 7.2-7.4.     

Presence of polioviruses and other enteral viruses in sewage: a survey in the Czech Socialistic Republic 1969-1976

Monitoring polioviruses in sewage is a permanent task within the poliomyelitis vaccination control programme in Czechoslovakia. The results of sewage examination in certain localities of the CSR in the years 1969 to 1976 are reported. During the study years, nearly 3600 samples of sewage were examined. The yield was about 9 percent of samples positive for polioviruses and 22 per cent of samples positive for other viruses. The virus positivity rate was roughly the same in samples from municipal sewers and samples from children's facilities. The majority of polioviruses were detected within 3 to 4 months after mass vaccination campaigns, which in Czechoslovakia are carried out in spring. In some years types 2 and 3 polioviruses tended to occur in later months after vaccination as well. Antigenic characterization of the polioviruses isolated in Prague showed that polioviruses possessing an rct+ marker and antigenically related but not identical with the original vaccine strains were sometimes present late during the intervals between vaccination campaigns. It may be assumed that vaccine strains which have been in circulation for sufficiently long time are subject to a gradual change or that vaccine-like strains have been imported.     

Long-term use of high-efficiency vacuum cleaners and residential airborne fungal-spore exposure

Exposure to fungal allergens is an important contributor to allergic respiratory disease, but information on the efficacy of residential fungal allergen-avoidance in allergic-disease management is lacking. Using vacuum cleaners with high-efficiency exhaust filtration is one method recommended for reducing residential allergen exposure levels, but their use to reduce fungal-spore exposure levels has not been evaluated. To evaluate the effectiveness of high-efficiency vacuuming to control airborne fungal-spore levels, fungal bioaerosols were repeatedly assessed over the course of 10 months in homes randomly assigned to groups using either conventionally filtered (control) or high-efficiency-filtered vacuum cleaners for routine vacuum cleaning. Air samples were analyzed for three fungal-spore categories representing taxa with predominantly outdoor sources and one representing taxa that commonly have indoor sources. In a two-way analysis of variance, sampling period had a significant effect on mean levels of all fungal-spore categories. Vacuum cleaner type had a marginally significant effect on the indoor spore category, with one high-efficiency vacuum group mean (of three) significantly lower than one control mean. No effect was observed of vacuum cleaner type on outdoor spore categories. Including home-environment variables in analysis of covariance models strengthened the effect of the vacuum-type treatment on the indoor spore category, with no effect on the three outdoor spore categories. Decreased indoor spore levels vs. controls were only observed in high-efficiency vacuum groups during the last sampling period, at the end of the heating season. The results suggest that using a vacuum with high-efficiency filtered exhaust could have some modest effectiveness in controlling airborne fungal-spore exposure in homes when infiltration of outdoor air is very limited.     

Aluminium Stress Affects Nitrogen Fixation and Assimilation in Soybean (Glycine max L.)

Nitrogen fixation and assimilation in nodules and roots were studied in soybean (Glycine max L.) exposed to different levels of aluminium (Al) stress (0, 50, 200 and 500 μM). Al at 500 μM induced oxidative stress, which became evident from an increase in lipid peroxidation accompanied by a concomitant decline in antioxidant enzyme activities and leghaemoglobin breakdown. Consequently, there was also a reduction in nitrogenase activity. However, the leghaemoglobin levels and nitrogenase activity were unexpectedly found to be higher in nodules when the plants were treated with 200 μM Al. Of the enzymes involved in nitrogen assimilation, the activity of glutamate dehydrogenase-NADH was reduced in nodules under Al stress, but it was significantly higher in roots at 500 μM Al as compared to that in the control. In nodules, the glutamine synthetase/glutamate synthase-NADH pathway, assayed in terms of activity and expression of both the enzymes, was inhibited at >50 μM Al; but in roots this inhibitory effect was apparent only at 500 μM Al. No significant changes in ammonium and protein contents were recorded in the nodules or roots when the plants were treated with 50 μM Al. However, Al at ≥200 μM significantly increased the ammonium levels and decreased the protein content in the nodules. But these contrasting effects on ammonium and protein contents due to Al stress were observed in the roots only at 500 μM Al. The results suggest that the effect of Al stress on nitrogen assimilation is more conspicuous in nodules than that in the roots of soybean plants.     

Immunohistological signposts in central nervous system tumours with neuronal differentiation.

25 neuronal tumours with a panel of antibodies were studied and it was found that vimentin was present in 15 tumours. It was also found in a few cells within rosettes. PGP 9.5 showed a somatic pattern of staining with nuclear and perinuclear positivity in 23. Neurofilament reactivity was found in 14. Retinal S-antigen was detected only in one medulloblastoma, 3/4 pineal tumours and 2/2 retinoblastomas. Reactivity, for synaptophysin was present in 2/5 medulloblastomas, 3/10 neuroblastomas and 2/2 retinoblastomas. GFAP was demonstrated in scattered tumour cells in 4/5 medulloblastomas. Two of these were the only tumours featuring bipolar differentiation whilst it was unipolar in the remainder. The significance of these findings in relation to the ontogeny of these tumours is discussed.     

Development of a microtitre plate indirect ELISA for measuring cortisol in teleosts, and evaluation of stress responses in rainbow trout and gilthead sea bream

A microtitre plate indirect enzyme‐linked immunoassay (ELISA) was developed for measuring plasma cortisol levels in rainbow trout Oncorhynchus mykiss, gilthead sea bream Sparus auratus sea bass Dicentrarchus labrax and Senegalese sole Solea senegalensis. Covalink microplates pretreated with disuccinimidyl suberate were coated with bovine serum albumin (BSA) conjugated to cortisol‐3‐carboxymethyl oxime. After blocking with BSA, competition was started by addition of plasma samples and anti‐cortisol antibody raised in rabbit. Goat anti‐rabbit IgG conjugated‐peroxidase was added as second antibody and then incubated with orthophenylenediamine as substrate. Reaction was stopped with 0·1 M HCl and absorbance was read at 450 nm in an automatic plate reader. The standard curve was linear from the lower limit of sensitivity of the assay (c. 0·3 ng ml^?1) to c. 3000 ng ml^?1. Dose‐response inhibition curves using serially diluted plasma samples of four species consistently showed parallelism with the standard curve using cortisol. The ELISA satisfied the strictest criteria of specificity (cross‐reactivity of anti‐cortisol antibody with testosterone, progesterone and 17ß‐oestradiol was negligible, cross‐reactivity with cortisone, corticosterone and 11‐deoxycortisol, was 1·5, 1 and 0·1%, respectively), reproducibility (interassay CV <6%), precision (intra‐assay CV <4%), and accuracy (average recovery >98%). Plasma cortisol concentration in rested fishes was in the range of 5–30 ng ml^?1. To physiologically validate the technique, changes in plasma cortisol concentrations were also measured in plasma of rainbow trout and gilthead sea bream following an acute 15 min chasing or 3 min air‐exposure stress, respectively. In both species plasma concentrations of cortisol, glucose and lactate rose significantly with respect to controls, showing concentrations similar to those reported previously for these species under similar stress conditions. Furthermore, gilthead sea bream chronically stressed by maintaining for 14 days under increased stocking density conditions also showed increased concentrations of plasma cortisol and glucose. These results validate the indirect ELISA technique developed for use in the evaluation of plasma cortisol concentration of at least four fish species.