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A fourth known species of Entovalva (Mollusca: Galeommatoidea), found in the esophagus of Holothuria spinifera and Holothuria leucospilota from Nha Trang Bay, Viet Nam, is described. Morphologic comparisons with the 3 previously described species are presented and the first DNA sequences for Entovalva are provided. Entovalva nhatrangensis, n. sp., differs from Entovalva mirabilis Voeltzkow, 1890 in its body shape, folded outer body epithelium, and lack of ovary in the foot. It differs from Entovalva (Cycladoconcha) amboinensis (Spärk, 1931) in its body shape and folded outer body epithelium. It differs from Entovalva lessonothuriae Kato, 1998, in shape of its foot. Two partial cytochrome oxidase I sequences for species diagnostic use have been submitted to GenBank.

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The genetic relationships among 11 taxa, belonging to the genus Contracaecum (C. osculatum A, C. osculatum B, C. osculatum (s.s.), C. osculatum D, C. osculatum E, C. osculatum baicalensis, C. mirounga, C. radiatum, C. ogmorhini (s.s.), C. margolisi) and Phocascoris (Phocoscris cystophorae), parasites as adults of seals, were inferred from sequence analysis 1519 bp) of the mitochondrial cytochrome c oxidase subunit II (mtDNA cox2) gene. Phylogenetic analyses obtained from Parsimony (MP) and Neighbour-Joining (NJ) K2P distance values generated similar topologies, each well supported at major nodes. All analyses delineated two main clades: the first encompassing the parasites of the phocid seals, i.e. the C. osculatum species complex, C. osculatum boicolensis, C. mirounga and C. radiatum, with the latter two species forming a separate subclade; the second including the parasites of otarids, i.e. C. ogmorhini (s.s.) and C. margolisi. An overall high congruence between mtDNA inferred tree topologies and those produced from nuclear data sets (20 allozyme loci) was observed. Comparison of the phylogenetic hypothesis here produced for Controcaecum spp. plus Phocascaris with those currently available for their definitive hosts (pinnipeds) suggests parallelism between hosts and parasite phylogenetic tree topologies.

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A total of 1432 hilsa shad, Tenualosa ilisha (=Hilsa ilisha) from 11 fresh water, brackish water and marine localities in Bangladesh yielded 13 adult Goezia bangladeshi n. sp., all specimens being found in the intestine of a single fish host caught in the lower Ganges. A total of 2372 Goezia juveniles were recovered from 490 infected fish (prevalence 34.2%). This is the first Goezia species recorded from Bangladesh, and it differs from other valid species by the number of caudal papillae (pre 7-9, para 3, post 6); encircled by tiny spines, the position of double papillae, the arrangement of body spines, and the length ratio of the intestinal caecum and the ventricular appendix (1: 3.33-4.72). Juveniles were free in the gut, embedded in the gut wall and encapsulated in mesenteries. Tenualosa ilisha serves as the definitive host, but the predominance of juveniles may indicate that piscivorous hosts may also serve as such. A list of the nominal Goezia species with important characters is provided.

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Nuclear-encoded large-subunit ribosomal DNA sequences were used to infer a phylogenetic hypothesis for 17 taxa (16 nominal species) of the genera Contracaecum and Phocascaris. Phylogenetic trees based on these data have been used to assess the validity of the taxonomic distinction between these genera, which was based on the presence or absence of certain structural features, rather than on explicit hypotheses of evolutionary history. Phylogenetic hypotheses based on parsimony, likelihood, and neighbor-joining analyses of these sequence data strongly support the hypothesis that species of Phocascaris are nested within the clade of Contracaecum species hosted by phocid seals, and are more closely related to species of the Contracaecum osculatum complex than to other Contracaecum species. Alternative tree topologies representing Phocascaris as not nested within the C. osculatum complex were significantly worse interpretations of these sequence data. Phylogenetic analysis also provides strong support for the monophyly of all taxa (Contracaecum and Phocascaris) from phocid seals, which is consistent with Berland's (1964) proposal that such species form a natural group; however, his proposal to recognize all species in phocid seals as Phocascaris, with all species from birds as Contracaecum would result in a paraphyletic Contracaecum, according to the molecular phylogenetic hypothesis.

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Five genetically distinct and reproductively isolated species have been detected previously within the morphospecies Pseudoterranova decipiens from the Arctic-Boreal, Boreal and Antarctic. Morphological analysis was carried out on male specimens identified by genetic (allozyme) markers, allowing the detection of significant differences at a number of characters between two members of the P. decipiens complex, namely P. decipiens A and B. On the basis of such differences, the nomenclatural designation for the two species is discussed. The names Pseudoterranova krabbei n. sp. and P. decipiens (sensu stricto) are proposed for species A and B, respectively. Morphological and genetic differentiation between the two species is shown using multivariate analysis. Allozyme diagnostic keys for routine identification of the four members of the P. decipiens complex, namely P. decipiens (s.s.), P. krabbei, P. bulbosa and P. azarasi, irrespective of sex and life-history stage, are provided.

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Mediterranean strains of Prorocentrum minimum do not appear to have the same toxic component as Japanese strains since they showed no cytotoxicity for hepatocytes in culture. However, their toxic components, which appear to block calcium channels, were detectable by the immobilisation test on Diptera larvae. A bio-accumulation experiment in the laboratory showed that the toxins could accumulate in nearly equivalent amounts in the hepatopancreas and meat of cultured mussels. The same toxicity was found in natural samples collected in a period of bloom of P. minimum. These results suggest that P. minimum could be responsible for shellfish toxicity in the natural environment and thus present a risk for human health.

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Infection with Pseudoterranova decipiens in 45 common seals (Phoca vitulina) from the outer Oslofjord was investigated. Seals were collected before and during the phocine distemper virus epizootic in 1988 when the seal population in the area was reduced from about 350 to 100. In 1989, cod (Gadus morhua) and other fish species were sampled for comparison with earlier investigations on prevalence and abundance of P. decipiens infection in fishes from the outer Oslofjord. Seventy-two per cent of cod were infected with P. decipiens larvae in shallow waters between the seal skerries; the corresponding abundance was 2.2. At other fishing sites at increasing distances from the seal colony, abundance dropped to 0.05-0.20. Otoliths recovered from stomachs and scats indicated that gadids (Micromesistius poutassu, Trisopterus esmarkii and G. morhua) made up more than 80% of the seal diet. Bullrout (Myxocephalus scorpius) was also heavily infected with P. decipiens (prevalence 93% and abundance 8.4), but was not found in the seal diet. However, uninfected cod that enter shallow water from the surrounding deep waters became infected when they feed on bullrout. Recruitment to mature stock of P. decipiens occurs when highly infected cod are eaten by seals. The number of reproducing P. decipiens is very low in common seals. Only 2 seals (i.e. less than 5% of the sample) were simultaneously infected with mature worms of both sexes. The dramatic reduction of the seal stock in the outer Oslofjord by the epizootic did not seem to affect the abundance of P. decipiens in its intermediate hosts.

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Genetic variation within and between population samples from 22 locations of the Atlantic Arctic-Boreal region, including 1657 specimens morphologically assigned to Contracaecum osculatum, was electrophoretically analysed at 17 loci. Highly significant deviations from the Hardy-Weinberg equilibrium were found at various loci in several samples, owing to the existence of three distinct gene pools within C. osculatum (sensu lato) from the study area. These gene pools correspond to three biological species (provisionally designated A, B and C), characterized by distinct genotypes at several diagnostic loci. Reproductive isolation between C.osculatum A, B and C is confirmed by the lack of F1, recombinant, or backcross genotypes in sympatric areas, despite the occurrence of multiple infections. Mean heterozygosity per locus is on average 0.11 in species A, 0.10 in B and 0.07 in C. High levels of gene flow were found within each of the three species, the values of Nm (number of migrant individuals) ranging from 3.41 (C. osculatum C) to 5.77 (C. osculatum A). Average Nei's genetic distance is 0.46 between A and B, 0.50 between A and C and 0.77 between B and C. From these values, times of evolutionary divergence from 2 to 4 million years can be estimated. Genetic relationships among populations and species of the C. osculatum complex are illustrated by principal component analysis. The role of both geographical isolation and host preferences in the speciation of C. osculatum (sensu lato) is discussed. A morphological distinction of the three species has not yet been possible (sibling species). However, there is evidence that the name C. osculatum (sensu stricto) should be used for species C, which shows a geographical distribution and definitive host corresponding to the neotype of C. osculatum (sensu stricto). Finally, a comparison is made between the members of the C. osculatum complex from the Atlantic Arctic-Boreal region and those of the Pseudoterranova decipiens complex from the same area, as to: (i) times of evolutionary divergence, (ii) geographical distribution, and (iii) host preferences.

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Elderly patients with persistent unexplained fever require a diagnostic evaluation that focuses on specific infections (eg, occult abdominal abscess, bacterial endocarditis, miliary tuberculosis), rheumatic disorders (eg, temporal arteritis, polyarteritis nodosa), and neoplasms (eg, lymphoma, nephroma). Assessment is directed by the subtle clues elicited from meticulous, repeated history taking and physical examination. Therapeutic trials or exploratory laparotomy may be appropriate but should not be attempted out of a sense of frustration.

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The distribution of Pseudoterranova decipiens C helps demonstrate the ecological basis of this genetically defined sibling species. In northern Norwegian waters the major fish intermediate host is Hippoglossoides platessoides. Overall prevalence, mean intensity and intensity range in H. platessoides were 15%, 16.5 and 1-165, respectively. Outside the range of its only known definitive host, the seal Erignathus barbatus, the parasite was not found in the same intermediate host.

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The community of benthic dinoflagellates of Mayotte Island is similar to those of other regions. Four clones of Gambierdiscus toxicus and of other benthic dinoflagellates species (Prorocentrum spp., Ostreopsis sp., Amphidinium spp.) have been isolated and screened for their crude toxicity using mouse-test. The toxigenic reservoir seems moderated. One toxic clone of G. toxicus has been studied for factors governing growth and photosynthetic activity of this species: salinity, temperature, light intensity and nutrients with bioassays.

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Evolution of the Gambierdiscus toxicus populations during the 1979/1985-1991 period shows an increase of the average densities until 1988-Sept. that seems linked with climatic parameters (insolation, rainfalls) but mainly with anthropogenetic disturbances. After a bloom the populations are now stabilized at a level higher than at the beginning of the monitoring. Without clear correlation, Gtx densities seems associated to physical and chemical features of the lagoonal and reefal waters.

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Genetic variation of 1017 specimens of codworm, Pseudoterranova decipiens, collected from fish and seals at 23 sampling locations in the North Atlantic and Norwegian and Barents Seas, was analysed on the basis of 16 enzyme loci. Three reproductively isolated species, provisionally designated P. decipiens A, B and C, were detected, showing distinct alleles at the following loci: Mdh-1, 6Pgdh, Np, Pgm, Est-2 (between species A and B); Mdh-3, 6Pgdh, Np, Sod-1, Adk, Pgm, Est-2, Mpi (between A and C); Mdh-1, Mdh-3, Sod-1, Adk, Pgm, Est-2, Mpi (between B and C). One F1 hybrid was observed between P. decipiens A and B, but this apparently does not lead to any gene exchange between the two species, which do not show any evidence of introgression. No hybrids or introgressed individuals were observed between P. decipiens C and either A or B. Genetic distances among conspecific populations were low (average Nei's D 0.001-0.005), even though they were collected thousands of kilometres apart, indicating high levels of gene flow within each of the three species. The values of Nei's index D were 0.44 between P. decipiens A and B, 0.57 between B and C, and 0.79 between A and C. Estimated evolutionary divergence times, using Nei's formula, range from 2 to 4 million years. Differences between P. decipiens A, B and C were also found with respect to genetic variability, morphology, geographical distribution and hosts. Mean heterozygosity values of 0.08, 0.05 and 0.02 were obtained for P. decipiens A, B and C, respectively. Preliminary morphological examination of adult males, previously identified by multilocus electrophoresis, revealed differences in the relative size and pattern of caudal papillae. P. decipiens B is widespread in the study area, whereas P. decipiens A was found only in the North-East Atlantic and Norwegian Sea. In this area P. decipiens A is most common in the grey seal, Halichoerus grypus, while the common seal, Phoca vitulina, is the main host for P. decipiens B. In Canadian Atlantic waters, where P. decipiens A is apparently absent, P. decipiens B infects both grey and common seals; a few specimens were also found in the hooded seal, Cystophora cristata. The only definitive host so far identified for P. decipiens C is the bearded seal, Erignathus barbatus; P. decipiens C appears to be widespread, occurring in both the North-West Atlantic and Barents Sea.

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STUDY OBJECTIVE: To compare the characteristics of restrained patients with those of unrestrained patients by assessing a number of medical, behavioral, and cognitive variables including a disruptive-behavior inventory. DESIGN: Case-control study. SETTING: A 719-bed university-affiliated teaching hospital. PATIENTS: The 80 cases were patients identified by the nursing staff as having had a restraint applied within the last 24 hours prior to entry in the study. The 80 unrestrained controls were selected from the rooms adjacent to the cases' in order to match for proximity to the nursing station and nurse staffing. MEASUREMENTS AND MAIN RESULTS: Demographic data, data on diagnoses and treatments, results of the Folstein Mini-Mental State (MMS) test and an eight-item disruptive-behavior inventory, and outcome information were obtained for each patient using a standardized procedure. Three important patient characteristics were significantly associated with restraint use in a multiple logistic regression model: disruptive behaviors, nursing assessment of risk of falling, and cognitive impairment. Cases were older than controls, but age was not an independent characteristic associated with restraint use when controlling for cognitive impairment, risk of falling, and disruptive behaviors. CONCLUSIONS: Restraint use was more likely in patients with disruptive behaviors, at risk of falling, and with cognitive impairment. Attention to these factors and alternative strategies for dealing with them may reduce the use of physical restraints.

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Maggots of an unidentified species of Caliphora were discovered in freshwater fish, Astyanax mexicanus fasciatus, shipped from Hong Kong to Norway. This represents the first reported case of myiasis in fish.

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