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The radioadaptive response, where a small priming dose of ionizing radiation can lessen the effects of subsequent exposure to a higher radiation challenge dose, was investigated in brain and liver within transgenic mice. Although it is well characterized in models in vitro, current radioadaptive response research has focused on particular cell types (i.e., lymphocytes) and does not provide comparative data for responses of multiple tissues within an organism. Transgenic animals are useful for such comparisons, because the transgene is integrated into all cells in the body. The pUR288 lacZ plasmid-based transgenic mouse model utilizes a plasmid vector allowing highly efficient recovery of mutational targets, including large size-change mutations that result from radiation exposure. Female C57Bl/6 pUR288 lacZ mice were exposed to priming doses of 0.075- to 0.375-Gy x-rays over a 3-d period. After 3 wk, they received an acute challenge dose of 2.5-Gy x-rays. Spontaneous mutant frequencies in lacZ were significantly higher in liver than in brain (6.62 × 10[sup -5] vs. 3.51 × 10[sup -5]). In the absence of a priming dose, the 2.5-Gy challenge doubled the mutant frequency of both liver and brain (13.38 × 10[sup -5], and 7.63 × 10[sup -5] respectively). Priming doses of 0.15, 0.225, and 0.375 Gy significantly reduced (by 40%) the mutagenic effects of the 2.5-Gy challenge in brain. Restriction enzyme analysis of rescued mutant plasmids revealed a decrease in large size-change mutations at the three priming doses in brain. This study demonstrates the utility of this model for the investigation of radiological processes of large size-change mutations, as well as showing a radioadaptive response in brain, but not liver, of mice in vivo. [ABSTRACT FROM AUTHOR]

Largemouth bass (Micropterus salmoides) were collected from locations with and without documented histories of pollution in Georgia and South Carolina. Whole blood samples were collected from over 3,000 bass and analyzed by flow cytometry to measure changes in cellular DNA content and cell cycle distribution. The coefficient of variation (CV)of the cell cycle phase G 0 /G 1 peak was used as a measure of variation in DNA content within an individual. The mean CV varied significantly among locations, and some locations withknown chemical or radioactive contaminants had higher CVs. Plotting the frequency distribution of CV values for each site revealed greater skewness and kurtosis in most locations with known contaminants. Ineach case, a right skewness indicated higher proportions of bass with unusually high CV in these locations. Aneuploid-like patterns were detected in the DNA histograms of five fish, all from locations with histories of contamination. The percentage of cells distributed amongphases of the cell cycle (G 0 /G 1 S, and G 2 /M) varied significantly among locations, but there was no apparent relationship to contaminant distribution. Differences in CV and frequency of aneuploids among sites with and without histories of pollution were generally small, but increased variation in DNA content may be associated with contaminant exposure at some locations. [ABSTRACT FROM AUTHOR]

Bioaccumulation of {sup}137{end}Cs was investigated in yellow bullhead catfish (Ameiurus natalis) inhabiting an abandoned reactor reservoir, Pond B, Savannah River Site, Barnwell Co., South Carolina. We collected fish by trap-netting, and determined ages from pectoral spines. Muscle and other tissues were assayed for{sup}137{end}Cs by NaI-scintillation. Muscle {sup}137{end}Cs was unrelated to sex (p = 0.859) or mass of fish (p = 0.224), but was related to age (p = 0.036). Examination of least-squares means suggested that {sup}137{end}Cs in muscle increased up to about age 3, but did not increase with greater age (means for 1, 2, 3, 4, 5, and 6 year olds were 2,630, 3,011. 3,513, 3,417, 3,599, and 3,339 Bq/kg, respectively). A modified Richards model showed equilibrium {sup}137{end}Cs concentration in muscle (3,625 Bq/kg) was acquired in approximately 2.4 vears. Growth differed between sexes (p less than 0.001), and the time to asymptotic body mass waslonger than the time to attain equilibrium {sup}137{end}Cs concentration. Males attained an asymptotic mass of 577 g in approximately 6.3years; females attained an asymptotic mass of 438 g in approximately5.9 years. The cumulative {sup}137{end}Cs burden of the population was 4.9 x 10{sup}6{end} Bq, representing less than 0.001% of the {sup}137{end}Cs inventory of the reservoir. Concentration of {sup}137{end}Cs varied among tissues (p less than 0.001), with gill and muscle thelowest and highest (634 and 3,712 Bq/kg, respectively). Concentration of {sup}137{end}Cs in ovaries declined with increasing ovary mass (p = 0.001; r{sup}2{end} = 0.60). Until equilibrium is attained in these fish, {sup}137{end}Cs concentration is directly related to increasing age rather than size. [ABSTRACT FROM AUTHOR]

One-year-old Atlantic salmon smolts were held in three artificial channels adjacent to a softwater (mean sp. cond. 30 Mu S cm-1), circumneutral stream. Water in one channel was untreated (mean pH6.25); the others received additions of acid (to mean pH 5.6), or acid plus aluminum (to mean pH 5.5; mean exchangeable Al 158 Mu g litre-1). Gills were sampled after 16 and 23 days of exposure for morphometric examination. On primary lamellae, chloride cells weremore numerous in both experimental treatments than in controls. In contrast, numbers of chloride cells on secondary lamellae were elevated only in fish exposed to acid without added Al. Chloride cell size and shape also varied with time and treatment. Fewer gill mucous cellswere found in fish exposed to acid plus Al than in controls. Chloride cell proliferation and structural changes may represent an attempt to compensate for increased ionic effluxes with low pH stress by increasing uptake. However, if Al concentrations are high, chloride cellsdo not proliferate along the secondary lamellae, or proliferating cells are damaged and lost. This may limit the potential to increase ionic uptake. [ABSTRACT FROM AUTHOR]

The United States breeding population of the wood stork (Mycteria americana) was listed as endangered in 1984; the U.S. Fish and WildlifeService has listed the determination of potential contaminant hazards as a task important to the recovery of the species. Storks nest in colonies and adult storks forage over wide areas and return with preyitems to feed to nestlings. The most recently consumed prey items are usually regurgitated by nestlings when they are handled. In 1995, over 200 food items from four wood stork colonies were collected whilebanding nestlings between 20 and 40 days old, and total mercury determined in individual food items. Two colonies were located on the Atlantic coast and two in inland areas. Overall dietary mercury concentration for each colony was calculated based on the biomass of each type of food item within the diet. Freshwater prey items had higher mercury concentrations than saltwater items most frequently chosen by storks. Daily Hg doses were estimated for a range of nestling sizes and daily food consumption rates. Risk factors were calculated based on two lowest observable adverse effect concentrations (LOAECs) from previous avian mercury ingestion studies. Based on one LOAEC, all four colonies in this study were at risk of sublethal effects due to mercuryin the diet of nestling wood storks. More extensive studies of sublethal effects in avian species from mercury contamination are necessary for more accurate risk assessment. [ABSTRACT FROM AUTHOR]

Mercury pollution is a serious problem in some areas of the southeastern United States. Due to biomagnification, long-lived predators should have high Hg concentrations in affected areas. American alligators (Alligator mississippiensis) are important predators in many Southwestern wetlands, but little information is available on Hg concentrations in this species. We collected tissues from alligators inhabitingtwo sites in the Everglades, Florida (n = 18) and a manmade reservoir in South Carolina (Par Pond; n = 44), all with documented historiesof Hg contamination, and analyzed them for total Hg. Mean concentrations in kidney, liver, muscle, and dermal scutes of alligators from the Everglades (expressed as mg Hg/kg dry mass q S.E.M.) were 36.42 q 5.23, 41.09 q 5.90, 5.57 q 0.47, and 5.83 q 1.04, respectively. Concentrations in liver, muscle, and scutes from Par Pond alligators were 17.73 q 2.56, 4.08 q 0.46, and 4.58 q 0.63, respectively. Blood from Par Pond alligators contained 2.20 q 0.38 mg Hg/kg wet mass. Mercury concentrations did not differ among sexes at any location. Tissue Hg levels did not differ significantly between Everglades locations, butwere lower in Par Pond. In Everglades alligators, Hg concentrations in all tissues were positively correlated, as were tissue Hg and total length. Only total length and scute Hg were correlated in Par Pond alligators. Regression revealed a significant relationship between muscle and scute Hg concentrations in Everglades alligators, but not Par Pond alligators. Alligators living in polluted areas can accumulatesubstantial concentrations of Hg, but relationships among Hg concentrations in specific tissues may vary with location or age and size ofthe animals sampled. [ABSTRACT FROM AUTHOR]

Disability and mental ill-health may be especially prevalent in Somalia, largely due to a protracted armed conflict and its consequent humanitarian crises. Little, if any, research to date, however, has simultaneously explored disability- and mental health-related factors in the Somali context. Using both descriptive and regression analytical techniques, we aimed to determine how increasing levels of functional impairment reported across different disability domains (i.e., visual, hearing and cognition), number of concomitant disabilities, and other empirically supported variables (such as employment and sex) are associated with the likelihood of self-identifying the need for mental health support among a sample ( N  = 1,355) of Somalis with disabilities, as well as identify the common barriers to such support. Despite most participants self-identifying a need for mental health support, only 15% were able to access it, with the most common barriers being the cost of services and the unavailability of local services. Being female, married, and having increasing levels of functional difficulty in the cognitive, mobility and self-care domains of disability were each significantly associated with an increased likelihood of the self-identified need for mental health support. This study's findings highlight potential points of prioritisation for mental health policy and programming in Somalia. A Somali version of this abstract can be found in the Supplementary Material., Competing Interests: M.A.J. is employed by the National Disability Agency of Somalia; A.H.A and K.Y. are employed by the UN Human Rights and Protection Group Somalia. C.Z., F.V. and C.J. declare no conflicts of interest., (© The Author(s) 2024.)

Background: Stroke acquired communication impairments impede effective communication. Consequently, in stroke care, communicative interactions can be challenging for both patients and staff and can predispose patients to increased risk of preventable adverse events. Communication partner training (CPT) can mitigate such negative outcomes by optimising communicative interactions. Providing CPT to student health and social care professionals (SH&SCPs) has the potential to enhance their clinical expertise and experiences and enhance the future clinical care of patients with stroke acquired communication impairments. This research aims to expand our understanding of how CPT is operationalised for SH&SCPs in higher education institutions and determine: what works; for whom; in what contexts; how and why?, Methods: This review is Phase 1 of a research project employing a realist approach with public and patient involvement (PPI). It incorporates five iterative steps: 1.) Clarifying the scope; 2.) Searching for evidence; 3.) Selecting and appraising evidence; 4.) Data extraction; 5.) Synthesising data and developing a middle range theory explaining how CPT is expected to work for SH&SCPs. An advisory panel, including PPI advisors, content advisors, student advisors, realist advisors and educationalist advisor has been set up to consult throughout the review and collaboratively agree the middle range theory., Discussion: While there is an evolving evidence base for CPT, including stroke specific CPT for SH&SCPs, it is acknowledged that there are challenges to its implementation in complex real-world settings. In combining empirical evidence with theoretical understanding, realist review permits synthesis of data from diverse sources and goes beyond determining efficacy to explore generative causation and solutions for real world practice. A middle range realist programme theory that coherently explains how CPT is expected to work when teaching SH&SCPs to communicate with people with stroke acquired communication impairments will provide educators with new insights into CPT development and implementation in their higher education institutions., Competing Interests: No competing interests were disclosed., (Copyright: © 2024 Fitzmaurice Y et al.)

Purpose: This paper describes a collaborative project between Trinity College Dublin in Ireland and the United Nations' World Food Programme (WFP) Mozambique country office. The Sphere standards require that information on humanitarian assistance should be in languages and formats accessible to people who cannot read or who have communication difficulties. Nevertheless, there remains a gap in both implementing this guidance consistently and in understanding the impact of doing so when engaging with affected populations., Method: This commentary describes the process of developing key messages regarding targeting of humanitarian food assistance in communication-accessible formats, and field testing of these materials with community committees and partners., Result: The communication-accessible materials were well received by communities, and humanitarian staff and partners found them to be useful in community engagement., Conclusion: Materials designed to be maximally accessible to people with communication differences and disabilities may also address inclusion for affected populations with different education, literacy, and language backgrounds. This commentary focuses on Sustainable Development Goal (SDG) 2 as an exemplar of the use of communication accessible messaging in humanitarian response.

Purpose: This commentary describes how a grassroot-led partnership initiated by members of the organisations World Federation of NeuroRehabilitation and Collaboration of Aphasia Trialists is addressing the marginalisation of people with aphasia, through education and knowledge exchange related to communication partner training of health professionals., Result: A partnership between academics and healthcare professionals across Austria, Denmark, Egypt, Ireland, Greece, India, Serbia and the United Kingdom was established in 2020. Through bimonthly online sessions in 2021-2022 a Danish communication partner training program was introduced while six teams adapted and translated the training and its materials to their local contexts., Conclusion: A collaborative partnership enabled multiple translations of an existing communication partner training program for healthcare professionals working with people with aphasia to support a sustainable delivery model that is linguistic and culturally sensitive. This commentary paper focusses on Sustainable Development Goal (SDG) 17 and also addresses SDG 10.

Purpose: This paper presents an analysis of interpersonal identity-based violence experienced by persons with communication disabilities in Iraq and the barriers reported to accessing supports. The use of communication accessible data collection tools is discussed as a means of enabling an inclusive response for multiple marginalised groups in relation to Sustainable Development Goals (SDGs) 16 and 5., Result: People with communication disabilities reported similar levels of interpersonal violence to those with disabilities of other types, characterised by high rates of deprivation and physical violence. Many participants did not seek support, but those that did were most likely to speak to a family member or friend, followed by consulting legal services. Barriers to accessing support were varied, with lack of transport being the most commonly reported. Satisfaction with research communication supports was high for all participants, including those with no communication difficulties, suggesting that the resources invested in communication access have benefits beyond those with communication disabilities., Conclusion: Iraqi persons with communication disabilities, like those with other disabilities, face high levels of interpersonal violence. The use of communication supports in research addressing disability is likely to increase the representation of persons with communication disability in study samples and can benefit participants with other disabilities. This commentary paper, available in Arabic as a supplemental file, focusses on SDG 16 and also addresses SDG 5.