The acceptability of Internet-based treatment and characteristics of an adult sample with obsessive compulsive disorder: an Internet survey

Background

Obsessive-compulsive disorder (OCD) is a disabling anxiety disorder, but most individuals delay seeking treatment. Internet-based cognitive behavioural therapy (iCBT) is an innovative service delivery method that may help to improve access to care, but the acceptability to consumers of such programs has not yet been established.

Methodology

People with symptoms of OCD were invited to complete an online survey enquiring about demographic characteristics, symptom severity, and acceptability of Internet-based treatment. Demographic and symptom severity data were compared with people with OCD identified in a national epidemiological survey and with a sample of patients with OCD from a specialist outpatient anxiety clinic.

Participants

129 volunteers to an online Internet survey, 135 patients at a specialist anxiety disorders outpatient clinic, and 297 cases identified in a national epidemiological survey.

Main Measures

Demographic characteristics, and severity of symptoms as measured by the Kessler 10-Item scale, the 12-item World Health Organisation Disability Assessment Schedule - Second Edition and the Yale Brown Obsessive Compulsive Scale - Self Report Version.

Principal Findings

The Internet sample was similar demographically but reported more severe symptoms than the comparison groups, although had similar severity of symptoms of OCD compared with other clinical samples reported in the literature. Participants reported Internet-based treatment for OCD would be highly acceptable.

Conclusions

Internet-based treatment may reduce barriers to accessing treatment to people with OCD. Individuals in this study were similar demographically to other samples and had similar severity of symptoms as those identified in other clinical samples, suggesting that Internet-based treatment using techniques employed in face-to-face treatment may be effective in this group. Internet-based treatments for OCD need to be developed and evaluated.     

N and P colimitation of N2-fixing and N-supplied fynbos legumes from the Cape Floristic Region

Background and aims

Legume species in the fynbos vegetation of the Cape Floristic Region, that fix N₂ in soils with low P, may have evolved for enhanced acquisition and efficient use of P. It was hypothesized that N₂-fixing and combined-N supplied (N-supplied) A. linearis, P. calyptrata and C. genistoides are adapted to low P and would be relatively unresponsive to increased P of 100 μM.

Methods

18 legume species were evaluated for their nodulation response to low P availability. The N X P interaction was then examined in A. linearis, P. calyptrata and C. genistoides reliant on either N₂-fixation or 300 μM N (NH₄NO₃), and receiving 0.1, 1.0, 10 and 100 μM P (NaH₂PO₄).

Results

In the species selection experiment, A. linearis, P. calyptrata and C. genistoides, with the greatest nodule fresh weight (FW) and nodule FW to root FW ratio, were the most prolific nodulating species. In the N X P experiment, with low P supply, the biomass of N₂-fixing P. calyptrata and C. genistoides was consistently greater than that of N-supplied plants. In contrast, with high P supply of 100 μM P, all N-supplied plants accumulated more biomass than the corresponding N₂-fixing plants. High P-use efficiency, poor down-regulation of P uptake and P storage was evident in A. linearis and P. calyptrata.

Conclusion

The growth response to P and the significant N X P interactions indicate that N₂-fixing and N-supplied plants were not adapted to low P, but rather colimited by both N and P.     

Estimating maturity from size-at-age data: Are real-world fisheries datasets up to the task?

Reviews in Fish Biology and Fisheries - The size and age at which individuals mature is rapidly changing due to plastic and evolved responses to fisheries harvest and global warming. Understanding...     

The mixed mating system of the sea palm kelp Postelsia palmaeformis: few costs to selfing

Naturally isolated populations have conflicting selection pressures for successful reproduction and inbreeding avoidance. These species with limited seasonal reproductive opportunities may use selfing as a means of reproductive assurance. We quantified the frequency of selfing and the fitness consequences for inbred versus outcrossed progeny of an annual kelp, the sea palm (Postelsia palmaeformis). Using experimentally established populations and microsatellite markers to assess the extent of selfing in progeny from six founding parents, we found the frequency of selfing was higher than expected in every population, and few fitness costs were detected in selfed offspring. Despite a decline in heterozygosity of 30 per cent in the first generation of selfing, self-fertilization did not affect individual size or reproduction, and correlated only with a marginally significant decline in survival. Our results suggest both that purging of deleterious recessive alleles may have already occurred and that selfing may be key to reproductive assurance in this species with limited dispersal. Postelsia has an alteration of a free-living diploid and haploid stage, where the haploid stage may provide increased efficiency for purging the genetic load. This life history is shared by many seaweeds and may thus be an important component of mating system evolution in the sea.     

In vivo analysis of the lumenal binding protein (BiP) reveals multiple functions of its ATPase domain

The endoplasmic reticulum (ER) chaperone binding protein (BiP) binds exposed hydrophobic regions of misfolded proteins. Cycles of ATP hydrolysis and nucleotide exchange on the ATPase domain were shown to regulate the function of the ligand-binding domain in vitro. Here we show that ATPase mutants of BiP with defective ATP-hydrolysis (T46G) or ATP-binding (G235D) caused permanent association with a model ligand, but also interfered with the production of secretory, but not cytosolic, proteins in vivo. Furthermore, the negative effect of BiP(T46G) on secretory protein synthesis was rescued by increased levels of wild-type BiP, whereas the G235D mutation was dominant. Unexpectedly, expression of a mutant BiP with impaired ligand binding also interfered with secretory protein production. Although mutant BiP lacking its ATPase domain had no detrimental effect on ER function, expression of an isolated ATPase domain interfered with secretory protein synthesis. Interestingly, the inhibitory effect of the isolated ATPase was alleviated by the T46G mutation and aggravated by the G235D mutation. We propose that in addition to its role in ligand release, the ATPase domain can interact with other components of the protein translocation and folding machinery to influence secretory protein synthesis.