Demographic and clinical characteristics of the participants.

<p>The figures in parentheses are either percentages or SD.</p><p>BDI-II: Beck Depression Inventory-II.</p><p>HPQ: World Health Organization Health and Work Performance Questionnaire.</p

Comparison of the intervention and control groups at the 4-month follow-up.

<p>The means and their 95% confidence intervals were estimated from maximum likelihood mixed effects models adjusting for stratification variables, age and gender.</p><p>The effect size was calculated from the difference in the means at 4 months divided by their pooled SD.</p><p>P-values compare the two groups and are from 1) a mixed model (using all randomized individuals, including those with missing follow-up data) which adjusted for stratification variables, age, and gender, 2) a t-test, and 3) a permutation test done within the 4 strata defined by baseline BDI and absenteeism. Permutation test is based on Monte-Carlo simulation with 1,000,000 samples (used to get exact distribution of t-statistic).</p>†<p>: Because this variable did not have the baseline measurement, the means at month 4 and their difference were examined by regression models adjusting for stratification variables, age and gender.</p><p>BDI-II: Beck Depression Inventory-II.</p><p>HPQ: World Health Organization Health and Work Performance Questionnaire.</p

Devising Assisted Reproductive Technologies for Wild-Derived Strains of Mice: 37 Strains from Five Subspecies of <i>Mus musculus</i>

<div><p>Wild-derived mice have long offered invaluable experimental models for mouse genetics because of their high evolutionary divergence from laboratory mice. A number of wild-derived strains are available from the RIKEN BioResource Center (BRC), but they have been maintained as living stocks because of the unavailability of assisted reproductive technology (ART). In this study, we sought to devise ART for 37 wild-derived strains from five subspecies of <i>Mus musculus</i> maintained at the BRC. Superovulation of females was effective (more than 15 oocytes per female) for 34 out of 37 strains by treatment with either equine chorionic gonadotropin or anti-inhibin serum, depending on their genetic background (subspecies). The collected oocytes could be fertilized <i>in vitro</i> at mean rates of 79.0% and 54.6% by the optimized protocol using fresh or frozen-thawed spermatozoa, respectively. They were cryopreserved at the 2-cell stage by vitrification with an ethylene glycol-based solution. In total, 94.6% of cryopreserved embryos survived the vitrification procedure and restored their normal morphology after warming. A conventional embryo transfer protocol could be applied to 25 out of the 35 strains tested. In the remaining 10 strains, live offspring could be obtained by a modified embryo transfer protocol using cyclosporin A treatment and co-transfer of ICR (laboratory mouse strain) embryos. Thus, ART for 37 wild-derived strains was devised successfully and is now routinely used for their preservation and transportation. The information provided here might facilitate broader use and wider distribution of wild-derived mice for biomedical research.</p></div

Full-term development of cryopreserved embryos after conventional or improved embryo transfer methods.

<p>Living offspring were obtained from all 37 strains with either the conventional (black) or the improved (gray) embryo transfer method. While 10 out of 35 strains failed to produce offspring by the conventional method, all strains tested produced offspring successfully by the improved method (33 strains). Offspring of the SWN strain were born in combination of embryos derived from natural mating and the improved embryo transfer method (asterisk). The detailed data set is available in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114305#pone.0114305.s006" target="_blank">Table S6</a>. N.T., not tested.</p

The mean numbers of oocytes collected per female after eCG or AIS treatment.

<p>Each bar shows the total number of oocytes consisting of normal ovulated oocytes (gray or hatched), abnormally ovulated oocytes (white), and unovulated ovarian oocytes (black). In 34 out of 37 strains, more than 15 oocytes per female were obtained either by eCG or AIS superovulation treatment. In <i>M. m. molossinus</i>, the strains known to be highly poor responders to eCG were not tested for eCG to save the number of animals used (shown as N.T.). The detailed data are summarized in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114305#pone.0114305.s001" target="_blank">Table S1</a>.</p

Comparison of the effectiveness of eCG and AIS treatments for superovulation.

<p>Strains that responded better to eCG than to AIS are indicated with white circles, and those that responded better to AIS than eCG are indicated with black diamonds. For MSM and JF1, the ratio was calculated from the date reported previously <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114305#pone.0114305-Hasegawa1" target="_blank">[13]</a>. Other strains without data for eCG (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114305#pone-0114305-g001" target="_blank">Figure 1</a>) are omitted from this figure. (A) Scatterplots displaying the comparative effectiveness of superovulation with eCG and AIS. The strains are grouped by ovals representing the subspecies so that the subspecies-specific tendencies can be observed. There was a significant effect of the superovulation regimen on the numbers of oocytes collected in <i>M. m. molossinus</i>, <i>M. m. domesticus</i>, and <i>M. m. spp</i> (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114305#pone-0114305-t002" target="_blank">Table 2</a>). (B) A world map showing the place of origin of wild-derived strains. There was a trend that strains from Asia were more AIS-sensitive and those from Europe and the North America were more eCG-sensitive.</p

The overall reproduction efficiencies in wild-derived strains and standard inbred strains (shaded).

<p>The efficiencies were calculated as the number of offspring produced from one superovulated female; i.e., the multiplication of the averages of the number of collected oocytes per female by eCG or AIS treatment, the fertilization rates with fresh spermatozoa, the survival rates of embryos cryopreserved with HOV method, and the birthrates after embryo transfer by conventional or improved method. For the SWN strain, the birthrate data were obtained from embryos derived from natural mating (asterisk) (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114305#pone-0114305-g005" target="_blank">Figure 5</a>). For standard inbred strains, refer to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114305#pone.0114305.s007" target="_blank">Tables S7</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114305#pone.0114305.s008" target="_blank">S8</a>.</p

Fertilization rates after IVF with fresh (gray) or frozen (black) spermatozoa.

<p>Strains are placed in the order of the fertilization rates using frozen spermatozoa. The detailed data set is available in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114305#pone.0114305.s005" target="_blank">Table S5</a>. N.T., not tested. Error bars = S.E.M.</p

List of the strain name and the origin in wild-derived strains.

<p>*MSM-Tyr^c and MSM-W^v strains are congenic strains carrying Tyr^c (albino) and KitW^−v mutations originating from laboratory strains, respectively. They have been repeatedly backcrossed to MSM eight and 15 times, respectively.</p><p>List of the strain name and the origin in wild-derived strains.</p