Evaluating a genetic counseling narrative group session for people who have tested positive for the Huntington's disease expansion: An interpretative phenomenological analysis.

Huntington's disease (HD) is an inherited neurodegenerative disorder characterized by motor problems, cognitive impairment, and mood disturbances. Given the emotional elements of both HD itself and the testing process for it, psychological interventions may be helpful for those families impacted by HD. A stand-alone genetic counseling narrative group has been offered by one regional genetics clinic in the north of England to support people's coping following predictive genetic testing for HD. Groups are held 4-5 times per year with patients attending a group on a single occasion. This study assessed participants' experiences of attending a group using the qualitative method interpretative phenomenological analysis (IPA). Telephone interviews were conducted with 12 people who had a mutation-positive HD predictive test result and who had taken part in a genetic counseling narrative group session between November 2017 and February 2018. Participants were asked about their experiences of the group and any impact it had had on their lives. Four themes emerged: 'The power of the group, 'Active elements of the narrative exercise', 'Subsequent impact of the session', and 'Another voice'. Participants described the positive impact of being able to meet and empathize with others in a similar situation, the group's positive impact on their mood and future outlook, and its beneficial impact on disclosure. While most participants were positive about the session, the final theme presented the voices of two participants for whom the groups were poorly timed. Given the sessions' generally positive impact, we recommend other centers consider offering people impacted by HD similar sessions.

Dissolved organic carbon reduces the toxicity of copper to germlings of the macroalgae, Fucus vesiculosus.

This study investigates the effects of waterborne copper exposure on germling growth in chemically defined seawater. Germlings of the macroalgae, Fucus vesiculosus were exposed to a range of copper and dissolved organic carbon (DOC as humic acid) concentrations over 14 days. Germling growth was found to be a sensitive indicator of copper exposure with total copper (TCu) and labile copper (LCu) EC(50) values of approximately 40 and 20 microg/L, respectively, in the absence of added DOC. The addition of DOC into the exposure media provided germlings with protection against copper toxicity, with an increased TCu EC(50) value of 117.3 microg/L at a corrected DOC (cDOC from humic acid only) concentration of 2.03 mg/L. The LCu EC(50) was not affected by a cDOC concentration of 1.65 mg/L or less, suggesting that the LCu concentration not the TCu concentration was responsible for inhibiting germling growth. However, at a cDOC concentration of approximately 2mg/L an increase in the LCu EC(50) suggests that the LCu concentration may play a role in the overall toxicity to the germlings. This is contrary to current understanding of aquatic copper toxicity and possible explanations for this are discussed.

Effects of dissolved organic carbon on the toxicity of copper to the developing embryos of the Pacific oyster (Crassostrea gigas).

The effects of humic acid (HA) on copper speciation and its subsequent toxicity to the sensitive early life stages of the Pacific oyster (Crassostrea gigas) are presented. Differential pulse anodic stripping voltammetry with a hanging mercury drop electrode was used to measure the copper species as labile copper (LCu; free ion and inorganic copper complexes) and total copper (TCu) with respect to increasing HA concentration. The TCu and LCu 50% effect concentrations (EC50s) in the absence of HA were 20.77 microg/L (95% confidence interval [CI], 24.02-19.97 microg/L) and 8.05 microg/L (95% CI, 9.6-5.92 microg/L) respectively. A corrected dissolved organic carbon (DOC) concentration (HA only) of 1.02 mg/L was required to significantly increase the TCu EC50 to approximately 41.09 microg/L (95% CI, 44.27-37.52 microg/L; p < 0.05), almost doubling that recorded when DOC (as HA) was absent from the test media. In contrast, the LCu EC50 was unaffected by changes in DOC concentration and was stable throughout the corrected DOC concentration range. The absence of change in the LCu EC50, despite increased HA concentration, suggests that the LCu fraction, not TCu, was responsible for the observed toxicity to the oyster embryo. This corresponds with the current understanding of copper toxicity and supports the free-ion activity model for copper toxicity.