Author Correction: The effects of aquarium culture on coral oocyte ultrastructure.

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The effects of aquarium culture on coral oocyte ultrastructure.

As the world's oceans are currently threatened by anthropogenic pollution and climate change, coral breeding has become an important conservation method, since it can limit marine organisms' exposure to sub-optimal environment conditions. However, the aquarium environment is inherently different from the ocean, and this could manifest in physiological changes in the reared organisms, particularly with respect to their reproduction. Therefore, the aim of this study was to observe and compare the ultrastructure of the oocytes from wild Oxypora lacera and Echinopora gemmacea with the oocytes from cultured corals using transmission electron microscope. The oocytes from Wild O. lacera and E. gemmacea were larger than cultured ones, though their microvillus layers were significantly thiner. Internally, lipid granule areas and yolk material density in the oocytes of wild O. lacera and E. gemmacea were ~25% lower than in their cultured counterparts. Food availability and the presence and availability of symbiotic dinoflagellates (genus Symbiodinium) may have played a role in driving these lipid-based differences, in particular, as cultured corals had limited potential for heterotrophic feeding. These data will aid in future coral husbandry efforts.

Cryopreservation of sperm from the coral Acropora humilis.

Corals are sensitive to minute changes in their environments, and their continued existence is substantially threatened by the increasing number of destructive anthropogenic activities and unprecedented rates of climate change. Although cryopreservation has been successfully to preserve mammalian gametes for decades, coral cryopreservation was attempted for the first time less than 15 years ago, and freezing protocols exist for only a handful of coral species. The present study developed a cryopreservation protocol for the sperm of the common Indo-Pacific reef-builder Acropora humilis. Colonies of reefs of Sattahip Bay, Chonburi Province, Thailand were collected from 3 m depth with a mesh net during a spawning event. Immediately after collection, the sperm were isolated and subjected to a two-step freezing method featuring DMSO, polyethylene glycol, or methanol as the cryoprotectant. Viability and motility were assessed via a bioluminescence technique and a "computer-assisted semen analysis, and it was found that a 15-min equilibration with 2 M DMSO followed by cooling at 41.7 °C was the optimum cryopreservation protocol for A. humilis sperm. The post-thaw sperm achieved 45% fertilization success, and 35% of the fertilized eggs developed into blastopore larvae. The present optimized protocol can therefore facilitate the preservation of sperm for future propagation efforts of this species and provide an experimental platform for optimizing cryopreservation protocols for gametes of other scleractinian coral species.

Validation of reference genes for cryopreservation studies with the gorgonian coral endosymbiont Symbiodinium.

Quantification by real-time RT-PCR requires a stable internal reference known as a housekeeping gene (HKG) for normalising the mRNA levels of target genes. The present study identified and validated stably expressed HKGs in post-thaw Symbiodinium clade G. Six potential HKGs, namely, pcna, gapdh, 18S rRNA, hsp90, rbcl, and ps1, were analysed using three different algorithms, namely, GeNorm, NormFinder, and BestKeeper. The GeNorm algorithm ranked the candidate genes as follows in the order of decreasing stability: pcna and gapdh > ps1 > 18S rRNA > hsp90 > rbcl. Results obtained using the NormFinder algorithm also showed that pcna was the most stable HKG and ps1 was the second most stable HKG. We found that the candidate HKGs examined in this study showed variable stability with respect to the three algorithms. These results indicated that both pcna and ps1 were suitable for normalising target gene expression determined by performing real-time RT-PCR in cryopreservation studies on Symbiodinium clade G. The results of the present study would help future studies to elucidate the effect of cryopreservation on gene expression in dinoflagellates.

Cryopreservation of the gorgonian endosymbiont Symbiodinium.

The study focused on finding a suitable cryoprotectant (CPA) and an optimum freezing protocol for the cryopreservation of the endosymbiotic dinoflagellates (Symbiodinium, clade G) of Junceella fragilis wherein the success of experiments is crucial to both scientific and ecology studies. A two-step freezing technique was developed. The viability of the thawed dinoflagellates was assayed using the adenosine triphosphate (ATP) bioassay for the first time and was further confirmed through the culturing of dinoflagellates in vitro. The results suggested that 30 min was the most suitable holding time for the dinoflagellates, and the samples produced highest viability when suspended at 5 cm from the surface of LN2. Results also showed that 1 M methanol with 0.4 M sucrose was the most effective CPA, yielding the highest viability (56.93%). Although cell densities of both cryopreserved and control group suffered an initial decline of culture, the cell densities were maintained throughout the remaining duration. In the present study, the cryopreservation of clade G endosymbiont algae was studied for the first time and the method described here could be applied for future studies on symbiotic algae cryopreservation.

Does cognitive-behavioural therapy promote meaning making? A preliminary test in the context of geriatric depression.

OBJECTIVES: This study examined the extent to which cognitive-behavioural therapy (CBT) for geriatric depression promoted meaning made of stress. DESIGN: Fifty-one participants received CBT and were assessed at pre- and post-treatment. METHODS: The primary outcome was the Integration of Stressful Life Experiences Scale (ISLES) and demographic factors were examined as moderators of changes over time. RESULTS: Those with more education showed improvement in their ability to regain positive values, worldviews, and purpose in life after a stressor. CONCLUSIONS: It appears that CBT promotes some forms of meaning made of stress for those with higher education. PRACTITIONER POINTS: Cognitive-behavioural therapy as it is routinely practiced may help highly educated older adults regain their Footing in the World (e.g., maintain positive values, worldviews, and purpose in life) in the aftermath of a stressful life event. Cognitive-behavioural therapy appears to offer fewer gains for less educated older adults (in terms of Footing in the World) as well as for other aspects of meaning-making, such as the ability to 'make sense' of a significant stressor. Although more empirical work is necessary, meaning-oriented interventions (e.g., 're-authoring' a fragmented self-narrative; Neimeyer, 2009, p. 97) hold promise as useful adjuncts to routine therapy that could augment outcomes.