Estimating recent growth in the cuttlefish Sepia officinalis: are nucleic acid-based indicators for growth and condition the method of choice?

A laboratory calibration study was undertaken with juvenile Sepia officinalis (80-85 g initial wet weight) to investigate the effects of different food rations and different starving intervals on RNA/dry weight (DW) ratios and RNA/DNA ratios in cephalopod mantle muscle at two different temperatures. The digestive gland index was also used as an additional indicator of recent growth. High food rations and low temperature went along with high RNA/DW ratios and high RNA/DNA ratios. Starving resulted in a linear decline in growth performance and a concomitant decrease in RNA/DW and RNA/DNA ratio, with RNA/DNA ratios representing the growth data better. RNA/DNA ratios decreased faster at higher temperatures. A fluorimetric assay for nucleic acid analysis was optimized for cephalopod mantle tissues and yielded reproducible RNA/DNA ratios with a relative variance below 10%. Thus, it may be possible to use this estimator of recently encountered feeding regime for the evaluation of mortality rates of early teuthid paralarvae to eventually support stock management. Also, log relative digestive gland weight showed a strong relationship with starving time, but, surprisingly, not with temperature. Data from the two temperatures analyzed could be combined to form a common regression line of relative digestive gland index with starving time. This indicator for recent growth might be especially suitable for large specimens with a well-developed digestive gland.     

The rapid detection of direct-acting DNA mutagens by electrical impedence with a DNA repair-deficient strain of Escherichia coli

A differential killing assay using Escherichia coli WP2 (wild type) and WP67 (uvrA, polA) was combined with impedence microbiology to produce a rapid screening method for direct-acting mutagenic compounds. The assay showed that mitomycin C, N-nitroso guanidine, potassium dichromate, sodium azide and acridine orange were direct-acting mutagens. With this method results can be obtained within hours, as compared with two days for the standard Salmonella/microsome test.     

Variation in Salmonella core lipopolysaccharide as detected by the monoclonal antibody M105

L.P. MANSFIELD, E. BILLETT, E. OLSEN AND S.J. FORSYTHE. 1996. The lipopolysaccharide antigenicity of 22 Salmonella strains (representing nine serogroups) and four non-salmonellae Enterobacteriaceae to the Salmonella genus specific monoclonal antibody M105 was analysed. The monoclonal antibody M105 reacted with all 22 Salmonella strains. Probing SDS-PAGE separated LPS molecules with MAb M105 revealed that the antibody reacted with the core region of all Salmonella serovars. However, no reaction was obtained to the long-chain LPS of serovars O ( Salm. adelaide and Salm. ealing ), C₁ ( Salm. infantis, Salm. livingstone and Salm. virchow ) or Salm. arizonae . It is plausible that the presence of a second core antigenic type results in the lack of reaction between long-chain LPS and the Salmonella genus specific monoclonal antibody M105.     

A recombination outside the BB deletion refines the location of the X linked retinitis pigmentosa locus RP3.

Genetic loci for X-linked retinitis pigmentosa (XLRP) have been mapped between Xp11.22 and Xp22.13 (RP2, RP3, RP6, and RP15). The RP3 gene, which is responsible for the predominant form of XLRP in most Caucasian populations, has been localized to Xp21.1 by linkage analysis and the map positions of chromosomal deletions associated with the disease. Previous linkage studies have suggested that RP3 is flanked by the markers DXS1110 (distal) and OTC (proximal). Patient BB was thought to have RP because of a lesion at the RP3 locus, in addition to chronic granulomatous disease, Duchenne muscular dystrophy (DMD), mild mental retardation, and the McLeod phenotype. This patient carried a deletion extending approximately 3 Mb from DMD in Xp21.3 to Xp21.1, with the proximal breakpoint located approximately 40 kb centromeric to DXS1110. The RP3 gene, therefore, is believed to reside between DXS1110 and the proximal breakpoint of the BB deletion. In order to refine the location of RP3 and to ascertain patients with RP3, we have been analyzing several XLRP families for linkage to Xp markers. Linkage analysis in an American family of 27 individuals demonstrates segregation of XLRP with markers in Xp21.1, consistent with the RP3 subtype. One affected mate shows a recombination event proximal to DXS1110. Additional markers within the DXS1110-OTC interval show that the crossover is between two novel polymorphic markers, DXS8349 and M6, both of which are present in BB DNA and lie centromeric to the proximal breakpoint. This recombination places the XLRP mutation in this family outside the BB deletion and redefines the location of RP3.     

Immunomagnetic separation as an alternative to enrichment broths for Salmonella detection

One hundred and twenty foodstuffs were tested for the enrichment of Salmonella species by immunoseparation. The foodstuffs covered six groups: raw chicken, prawns, skimmed milk powder, herbs and spices, cocoa powder and animal feed. Half of the food samples were spiked with one Salmonella species: Salm. ealing, Salm. enteritidis, Salm. give, Salm. typhimurium or Salm. virchow . Comparison of Salmonella recovery with standard methods (selenite cystine broth, tetrathionate broth and Rappaport-Vassiliadis broth) was carried out. Immunoseparation gave similar numbers of true positives to the standard enrichment methods in a short time period. Only immunoseparation isolated Salmonella species from spiked garlic granules demonstrating the possible recovery of sublethally injured cells.     

Locomotion in ground beetles (Coleoptera carabidae): An interpretation of leg structure in functional terms

Recordings of maximum running speeds and maximum horizontal pulling (= pushing) forces have been obtained for 72 species of cursorial and fossorial ground beetles (Carabidae: Coleoptera) belonging to 19 tribes and 12 supertribes. Fore leg, pro- and meso-femoral and tibial and mid leg measurements have also been made and all these parameters have been correlated with body lengths. It was found that those species (mainly Carabinae group I, i.e. Nebriini, Notiophilini, Loricerini, Elaphrini, Cicindelini) with relatively long, slender pro-and mesofemora, long pro - and mesotibiae and small meso-coxal articulations were faster runners (i.e. sprinters) but weaker horizontal pushers. In contrast, species (mainly Carabinae group II, i.e. Broscini, Trechini, Pogonini, Bembidiini, Patrobini, Pterostichini, Zabrini, Callistini, Oodini, Licinini, Harpalini) with relatively short, broad pro-femora, short (slender) mesofemora, short pro– and mesotibiae, and larger meso-coxal articulations were stronger horizontal pushers but were slower runners. Carabinae group III (Scaritini), however, which have very short, narrow pro- and mesofemora, very short pro- and mesotibiae, and large meso-coxal articulations were found to be very strong horizontal pushers but very slow (relatively) runners.
The Carabini (including Cychrini), however, resemble Carabinae group II in their running and pushing abilities although their legs are structurally similar to those of Carabinae group I (i.e. relatively long and slender with small meso–coxal articulations). In fact, species of Carabini are fast walkers, their prey is generally slow moving (i.e. slugs, snails and caterpillars) and they hunt in restrictive habitats such as weed patches, meadows or woodland grass which produce a considerable amount of environmental resistance. Most Carabini have a heavy, powerful body which seems to be well adapted to overcoming this resistance.     

Revenue allocation in the reorganized Health Service.

This paper recommends that the secrecy long associated with the allocation of Health Service revenue should be replaced by an objective formula applied to areas and districts. In this way the allocations should be "fairer" and the different tiers of management within the reorganized N.H.S. would have a greater incentive for the better use of their resources. The Department of Health and Social Security has demonstrated its desire to be frank and objective in revenue resource allocation and it new remains for the other tiers to follow suit.