Search

Abstract Background Epidermal pseudotumours from Hippoglossoides dubius and Acanthogobius flavimanus in Japan and gill lesions in Limanda limanda from the UK have been shown to be caused by phylogenetically related protozoan parasites, known collectively as X-cells. However, the phylogenetic position of the X-cell group is not well supported within any of the existing protozoan phyla and they are currently thought to be members of the Alveolata. Ultrastructural features of X-cells in fish pseudotumours are somewhat limited and no typical environmental stages, such as spores or flagellated cells, have been observed. The life cycles for these parasites have not been demonstrated and it remains unknown how transmission to a new host occurs. In the present study, pseudobranchial pseudotumours from Atlantic cod, Gadus morhua, in Iceland and epidermal pseudotumours from the northern black flounder, Pseudopleuronectes obscurus, in Japan were used in experimental transmission studies to establish whether direct transmission of the parasite is achievable. In addition, X-cells from Atlantic cod were sequenced to confirm whether they are phylogenetically related to other X-cells and epidermal pseudotumours from the northern black flounder were analysed to establish whether the same parasite is responsible for infecting different flatfish species in Japan. Results Phylogenetic analyses of small subunit ribosomal DNA (SSU rDNA) sequence data from Atlantic cod X-cells show that they are a related parasite that occupies a basal position to the clade containing other X-cell parasites. The X-cell parasite causing epidermal pseudotumours in P. obscurus is the same parasite that causes pseudotumours in H. dubius. Direct, fish to fish, transmission of the X-cell parasites used in this study, via oral feeding or injection, was not achieved. Non-amoeboid X-cells are contained within discrete sac-like structures that are loosely attached to epidermal pseudotumours in flatfish; these X-cells are able to tolerate exposure to seawater. A sensitive nested PCR assay was developed for the sub clinical detection of both parasites and to assist in future life cycle studies. PCR revealed that the parasite in P. obscurus was detectable in non-pseudotumourous areas of fish that had pseudotumours present in other areas of the body. Conclusions The inability to successfully transmit both parasites in this study suggests that either host detachment combined with a period of independent development or an alternate host is required to complete the life cycle for X-cell parasites. Phylogenetic analyses of SSU rDNA confirm a monophyletic grouping for all sequenced X-cell parasites, but do not robustly support their placement within any established protist phylum. Analysis of SSU rDNA from X-cells in Japanese flatfish reveals that the same parasite can infect more than one species of fish.

Intensification of food production has the potential to drive increased disease prevalence in food plants and animals. Microsporidia are diversely distributed, opportunistic, and density-dependent parasites infecting hosts from almost all known animal taxa. They are frequent in highly managed aquatic and terrestrial hosts, many of which are vulnerable to epizootics, and all of which are crucial for the stability of the animal-human food chain. Mass rearing and changes in global climate may exacerbate disease and more efficient transmission of parasites in stressed or immune-deficient hosts. Further, human microsporidiosis appears to be adventitious and primarily associated with an increasing community of immune-deficient individuals. Taken together, strong evidence exists for an increasing prevalence of microsporidiosis in animals and humans, and for sharing of pathogens across hosts and biomes.

The “sol–gel method” was used to prepare spherical chitosan-modified bentonite (SCB) hydrogels in this study. The SCB hydrogels were characterized and used as sorbents to remove tetracycline (TC) from aqueous solutions. The adsorbents were characterized by SEM, XRD, FTIR, TG, and BET techniques. Various characterization results showed that the SCB adsorbent had fewer surface pores and a specific surface area that was 96.6% lower than the powder, but the layered mesoporous structure of bentonite remained unchanged. The adsorption process fit to both the Freundlich model and the pseudo-second-order kinetic model showed that it was a non-monolayer chemical adsorption process affected by intra-particle diffusion. The maximum monolayer adsorption capacity determined by the Langmuir model was 39.49 mg/g. Thermodynamic parameters indicated that adsorption was a spontaneous, endothermic, and entropy-increasing process. In addition, solid–liquid separation was easy with the SCB adsorbent, providing important reference information for the synthesis of SCB as a novel and promising adsorbent for the removal of antibiotics from wastewater at the industrial level.

The transition to adulthood is a developmental phase which occurs as young people move from adolescence into adulthood. Young people with disabilities, including cerebral palsy (CP), and their families have reported challenges during the transition to adulthood because they are required to move to adult supports and services, which are often fragmented and bring about new questions and expectations to find necessary supports. Young people and their parents have been found to lack information about where to find services in adulthood, how to access the services and what to ask during the transitional process. The aim of this scoping review was to explore the information needs of young people with CP and their families during the transition to adulthood. The goal is to map the current published evidence within the transition to adulthood literature base to explore what is known about information needs during the transition to adulthood of young people with CP and their parents. This review seeks to synthesize what is known about information content, timing, methods of provision and delivery. Databases searched were OVID Medline, CINAL, ERIC, EMBASE, PsycINFO, Web of Science, Social Science Abstracts and Sociological Abstracts. Initially 675 articles were retrieved. Four hundred and forty-two articles were selected for title review. Two hundred and five articles remained for abstract review. Seventeen articles were included for full-text review. Eleven articles were included in this review. Data were organized into five themes: (1) identified information needs during the transition to adulthood (content), (2) identified recommended providers of information during the transition to adulthood (who), (3) identified delivery methods of information during the transition to adulthood (how), (4) identified timing of information delivery of information during the transition to adulthood (when) and (5) location of information provided during the transition to adulthood (where). This review found that young people with CP, their families and adult providers all possess information needs during the transition to adulthood. Young people with CP and their families seek information about what adult services will look like and how to access supports. Adult providers require information about CP. Youth with CP prefer individualized information be delivered to them when needed rather than presented in group sessions or via paper handout. Other recommendations included the development of parent support networks to assist parents in the transition to adulthood. The opportunity to learn from real-life experiences was also viewed as an important source of information as well as method to provide information.

A large (N = 603) and representative sample in Sri Lanka completed a questionnaire that assessed the salience of 11 social identities (nation, social class, age, religion, caste, occupation, race, gender, educational level, town or village of residence, and political party) within respondents' self-concepts. Consistent with extant psychological theories of identity, four features of an identity were found to be systematically related to its salience within the self-concept: (a) how the status of an identity affects one's overall self-esteem, (b) the degree to which one is a demographic minority on a category of identity, (c) whether an identity has been affected by processes of urban-industrial development, and (d) the type and extent of intergroup contact on a category of identity. The relevance of the identity framework to cross-cultural theory is discussed. [ABSTRACT FROM AUTHOR]