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At least 19 recordsLinked to original sources
PubMed1987

[Occupational eczema with photosensitivity caused by contact with Bryozoa].

Contact eczema to Bryozoa is a very invalidating fishermen's disease. Described in the North Sea ("Dogger Bank itch") and in the eastern Channel, it begins with the hands which have touched Bryozoa, these being microscopic "moss-like animals", unrelated to algae, which form coralliform, encrusting and filamentous colonies attached to the sea-floor. Sensitization results from handling nets (drag-nets and trammels) or, less frequently, fish trays. Bryozoa responsible for the disease are Alcyonidum hirsutum and, mostly, Alcyonidum gelatinosum. The case of occupational eczema presented here discloses two hitherto unrecognized allergens: another Bryozoa species, Electra pilosa, which proliferates in the early summer and forms encrusting colonies on various supports, and a sea-weed, Sargassum muticum, which up to now had not been held responsible for skin lesions. The summer outbreaks, from May to September, and the fact that the face and upper chest are involved are classically ascribed to the natural cycle of Bryozoa (colonies multiply in the warm season and regress in the winter) and to contact with uncovered parts of the body. The results of our photobiological exploration suggest that the distribution of the eczema might well be due to an additional photoallergic reaction.

Bryozoa↗
PubMed1992

The heptadecanoic fatty aldehyde--one of the main aldehydes of the far-eastern Bryozoa.

1. The relative content of 16:0, 17:0 and 18:0 fatty aldehydes in the lipids of eight species of the far-eastern Bryozoa was studied. 2. Heptadecanoic aldehyde is one of the main aldehydes in the seven species investigated comprising about 30% of the sum of these main bryozoan aldehydes. 3. We suggest the unusually high relative heptadecanoic aldehyde content in the lipids of Bryozoa may be helpful in settling some problems concerning their system.

Aldehydes↗
PubMed2004

Metabolic flexibility: the key to long-term evolutionary success in Bryozoa?

Oxygen consumption (MO2) and activity were evaluated in Antarctic Bryozoa. Three species representing two different morphologies, flat sheet, laminar forms, Isoseculiflustra tenuis and Kymella polaris, and the bush form Camptoplites bicornis were used. In Bryozoa, activity is measured as the proportion of colony zooids with their lophophores extended. In I. tenuis and K. polaris, residual analysis showed that the percentage of zooids with extended lophophores was not correlated with colony MO2. Lophophore extension is, therefore, a poor measure of activity, and other costs (e.g. growth, reproduction, storage) probably form the major metabolic costs. MO2 per unit of ash-free dry mass (AFDM) in the laminar forms was low compared with other Antarctic marine invertebrates, but not lower than brachiopods and echinoderms. However, the lowest rate here, 16.8 microg O2 g AFDM(-1) h(-1) for a K. polaris colony, is (to our knowledge) the lowest for any animal so far reported. MO2 per unit of AFDM for C. bicornis, however, is among the highest reported for sessile or slow moving Antarctic marine ectotherms, with values similar to those for bivalve and gastropod molluscs. The highest rate, 527 microg O2 g AFDM(-1) h(-1) for one colony is (to our knowledge) the highest reported for polar animals of this type. Extreme diversity in metabolic strategy may explain the bryozoan long evolutionary record and great success in shallow marine environments worldwide.

Adaptation, Physiological↗
PubMedDate not supplied

[Freshwater bryozoans (Bryozoa: Phylactolaemata) as vectors of salmonid disease].

Relations of PKX [vector of proliferative kidney disease (PKD)] of reared and wild Salmonoidea and Tetraspora bryozoides, the only genus and species of Myxozoa found in fresh water Bryozoa, is discussed using recent publications. Both organisms were found in several European countries as well as in North America. It seems that PKX is a Bryozoa parasite which do not undergo full cycle of sporulation in fish.

Animals↗
PubMed1977

[Systematic value of the larval structure and details of postlarval morphogenesis in Bryozoa gymnolaemates].

Among the various species of Bryozoa Gymnolaemata, the larvae and their development were studied, comparing the larval structure and the evolution of their cellular categories during the post-larval morphogenesis the existence of nine well-defined larval types could be revealed. Cases of insufficiently described larvae are discussed. The present systematic of Bryozoa Gymnolaemata is compared with the classification of various larval types. For the major part of cases, each systematic family is marked by a precise type of larva; however there are some exceptions, especially in the ordre Ctenostomata. These discordances may suggest some rearrangements of the classification utilized at the present time.

Animals↗
PubMed2006

The complete mitochondrial genome of Flustrellidra hispida and the phylogenetic position of Bryozoa among the Metazoa.

The complete mitochondrial genome of Flustrellidra hispida (Bryozoa, Ctenostomata, Flustrellidridae) was sequenced using a transposon-mediated approach. All but one of the 36 genes were identified (trnS2). The genome is 13,026 bp long, being one of the smallest metazoan mitochondrial genomes sequenced to date with a unique gene order when compared to other Metazoa. The genome has an overall AT richness of 59.4%. We found seven regions of overlaps between tRNAs and protein-coding genes ranging from 2 to 11 nt, and seven regions of overlap between tRNAs, ranging from 1 to 8 nt, resulting in a total number of 46 overlapping nucleotides. Genes nad4, cox2, atp8, and nad3 are terminated by the abbreviated stop codon T and cytb is suggested to terminate on (ACT)AA; we postulate that mRNA editing is required to remove AC for TAA to be functional in terminating translation. Phylogenetic analysis of nucleotide and amino acid data place Flustrellidra in the Lophotrochozoa. DNA for this study originated from two populations resulting in a contig consisting of multiple haplotypes. Twenty-seven SNP sites were detected, the majority occurring in cox1 and nad5. With cox1 already established as a marker in bryozoan studies, we advocate the further testing of nad5.

Amino Acid Sequence↗
PubMed2004

Adrenoceptor compounds prevent the settlement of marine invertebrate larvae: Balanus amphitrite (Cirripedia), Bugula neritina (Bryozoa) and Hydroides elegans (Polychaeta).

The effects of the neurotransmitter blockers idazoxan and phentolamine on the larval settlement of three marine invertebrate species belonging to three different phyla were investigated by using in vitro concentration-response bioassays. Since neurotransmitters are known to influence metamorphic transitions in invertebrate larvae, neurotransmitter blockers were tested to evaluated their sublethal effects on larvae. The alpha-adrenergic antagonists idazoxan and phentolamine inhibited settlement of Balanus amphitrite (Cirripedia), Bugula neritina (Bryozoa) larvae, and larvae of the polychaete Hydroides elegans (Polychaeta) in a concentration-and taxon-dependent manner. At concentrations of 10(-3) M of both agents, larvae of all three species became immobile and subsequently died within 24 h. While cumulative settlement rates were observed after 48 h for B. amphitrite and H. elegans, and after 5 h for B. neritina, >90% of the larvae that settled did so within 24 h for the first two species and within 1 h for B. neritina. The tendency of the hydrophobic idazoxan and phentolamine to accumulate at solid surfaces most probably contributes to their successful inhibition of larval settlement. This ability makes them particularly attractive as candidates for the development of slow-release carriers in antifouling paints.

Adrenergic alpha-Antagonists↗
PubMedDate not supplied

[Alcyonidium gelatinosum (L.) (Bryozoa) and cutaneous hypersensitivity reactions. Preliminary results of an experimental study].

The appearance of acute eczematous dermatitis in fishermen from the estuary of the Seine, about which the responsibility of Alcyonidium gelatinosum (L.) is still under discussion, led us to estimate the ability of this Bryozoa to induce cutaneous responses of delayed hypersensitivity. Intradermal tests carried out in guinea-pigs after subcutaneous, respiratory or percutaneous sensitization, gave evidence of a clear allergenic ability of this alcyonelline. The deposit of the biological product on normal skin during four consecutive days is enough to induce strong responses of delayed hypersensitivity. This experimental study needs further investigations in which the possible existence of anaphylactic reactions should be confirmed.

Animals↗
PubMed1997

A New Microsporidium, Nosema cristatellae n. sp. in the Bryozoan Cristatella mucedo (Bryozoa, Phylactolaemata)

A microsporidian infecting cells of the body wall of the phylactolaemate bryozoan Cristatella mucedo is described. All stages of the parasite are diplokaryotic and lie in direct contact with the host cell cytoplasm. Sporogony is probably disporoblastic. Spores measure 7.5 x 5.1 &mgr;m and have 22-32 coils of the polar tube arranged in several rows and a bell-like polaroplast of compact membranes. The parasite is assigned to the genus Nosema as a new species, Nosema cristatellae. It is differentiated from the previously described parasites of Alcyonella (=Plumatella) fungosa (Bryozoa), named Myxosporidium bryozoides and Nosema bryozoides, by spore characters and tissue specificity. Although it was found in a different species of bryozoan, it is not known whether N. cristatellae is infective to P. fungosa. Copyright 1997 Academic Press. Copyright 1997 Academic Press

Journal Article↗
PubMed2007

Sacculogenesis and sporogony of Tetracapsuloides bryosalmonae (Myxozoa: Malacosporea) within the bryozoan host Fredericella sultana (Bryozoa: Phylactolaemata).

Tetracapsuloides bryosalmonae is the myxozoan parasite responsible for proliferative kidney disease (PKD) of salmonid fishes. This disease affects farmed species in North America and Western Europe where it results in significant economic losses for the rainbow trout industry. The parasite has two hosts in its life cycle, salmonid fish, and freshwater bryozoans. In this study, we describe the development of the parasite at the ultrastructural level within the bryozoan host Fredericella sultana. Single celled, presaccular stages form aggregates within the metacoel of this host which resolve into spore sacs. Within these sacs sporogenesis is initiated with the differentiation of presporogonic cells into sporogonic and valvogenic cells. These latter cells surround a sporogonic cell which subsequently divides to form a sporoplasmogenic cell and a capsulogenic cell. The capsulogenic cell divides further to form four cells each with a polar capsule, while the sporoplasmogenic cell divides resulting in four cells, two primary cells and two secondary cells. The secondary cells are engulfed by the primary cells resulting in a mature sporoplasm. It is hypothesized that autogamy occurs during the initial formation of the spore sac and that allogamy is also possible during this time.

Animals↗
PubMed1982

Dogger bank itch. 4. An eczema-causing sulfoxonium ion from the marine animal, Alcyonidium gelatinosum [Bryozoa].

Repeated exposure to the marine bryozoan, Alcyonidium gelatinosum, frequently provokes an eczematous allergic contact dermatitis known as the "Dogger Bank Itch". The dermatitis, representing a severe occupational disease, is especially widely distributed among trawlermen working in the Dogger Bank area in the North Sea. The allergy is shown to belong to the type of cell-mediated hypersensitivity. The hapten has been identified as the (2-hydroxyethyl)dimethylsulfoxonium ion. The isolation, structure determination and synthesis are discussed.

Bryozoa↗
PubMed2003

Molecular phylogeny and phylogeography of free-living Bryozoa (Cupuladriidae) from both sides of the Isthmus of Panama.

Genetic data were used to identify Recent species of free-living bryozoans (Cupuladriidae) from both sides of the Isthmus of Panama, and to examine their phylogenetic relationships, species richness, and population structures. An approximately 480bp fragment of the 16S mitochondrial rRNA gene was sequenced from 182 individuals from Panama, the Gulf of Mexico, and El Salvador. Ten haplotype groups (Cupuladria 4, 5, and 6; Discoporella 1, 2, 3A, 3B, 3C, 7, and 8) were identified. Genetic distances between haplotype groups (3.2-26.5%; K2P+Gamma) were 1-2 orders of magnitude greater than within groups (0.1-1.4%). Seven of the haplotype groups represent morphologically distinct species; Discoporellas 3A-C appear to be cryptic species. Phylogenetic analyses identified two pairs of transisthmian sister clades. An average divergence rate derived from other taxa suggests that Cupuladrias 4 and 5 diverged approximately 7Ma, a Discoporella 7 clade diverged from a 3A-C clade approximately 11Ma, and the 3A-C clade radiated approximately 6-4Ma; these events all predated final closure of the isthmus? 3Ma. The Caribbean side of the isthmus, with 5 species, is only marginally richer in cupuladriids than the Pacific side, with 4, but has greater phylogenetic depth. The Caribbean retains lineages stemming from a New World Miocene radiation that are not represented in the eastern Pacific; extant eastern Pacific cupuladriids share most recent common ancestry with only two of the Caribbean lineages. Species in the eastern Pacific tend to show shallow population structures, with high levels of gene flow between geographically separate populations, whereas Caribbean species tend to show deeper populations structures, with indications of restricted gene flow between Bocas del Toro/Gulf of Mosquitos and Costa Arriba/San Blas. The population structures derive from Pleistocene histories and may be of limited value in interpreting the macroevolutionary pattern, as our results provide no evidence of speciation on either side of the isthmus following closure in the late Pliocene.

Animals↗
PubMedDate not supplied

Trichonosema algonquinensis n. sp. (Phylum microsporidia) in Pectinatella magnifica (Bryozoa: phylactolaemata) from Algonquin Park, Ontario, Canada.

A new species of microsporidian, Trichonosema algonquinensis, is described from a freshwater bryozoan, Pectinatella magnifica from Ontario, Canada. The parasite develops in epithelial cells and appears as white, spherical masses throughout the tissues. Trichonosema algonquinensis is diplokaryotic, diploblastic and undergoes development in direct contact with the cytoplasm of the host cell. Mature spores are ovoid, tapered at one end, and measure 8.5 +/- 0.3 x 4.4 +/- 0.1 microm. The polar filament is wound in 20 to 23 helical coils. Although the parasite resembles T. pectinatellae described from the same host in Michigan and Ohio, it differs in the length of the spore and number of coils of the polar filament. Analysis of 16S rDNA by maximum likelihood, parsimony and Baysian inference, complements the morphological data in supporting the placement of T. algonquinensis as a sister species of T. pectinatellae.

Animals↗
PubMedDate not supplied

Development and molecular characterisation of the microsporidian Schroedera airthreyi n. sp. in a freshwater bryozoan Plumatella sp. (Bryozoa: Phylactolaemata).

The development of a new species of microsporidian, infecting a freshwater Plumatellid bryozoan, is described. The small-subunit rDNA, internal transcribed spacer region (ITS), and partial large-subunit rDNA genes were sequenced. Phylogenetic analysis demonstrated that the parasite clustered with Schroedera plumatellae. However, while there were morphological affinities with this species, significant differences were also observed. The infection initially appeared as a roughening of the peritoneum lining the metacoelom of the bryozoan. This roughening resolved into meront-infected syncytia, composed of interconnected cells of the body wall that detached to float in the coleomic cavity. Spores were observed to develop within these syncytia. All stages of development were diplokaryotic in contrast to S. plumatellae, which has a distinct monokaryotic merogony preceding sporogony. The infection was pathogenic to the host. Direct bryozoan-bryozoan transmission was not observed. We propose to name the microsporidian Schroedera aithreyi n. sp.

Animals↗