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The current study assessed the success of masking omega-3 (Ω3) and psychotherapy in clinical trials of youth with depression or bipolar spectrum disorder. Participants were youth ages 7–14 with DSM-IV-TR diagnosed depressive (n = 72) or bipolar spectrum (n = 23) disorders. Inclusion diagnoses were depressive disorder, cyclothymic disorder, or bipolar disorder not otherwise specified. Exclusion diagnoses included bipolar I or II disorder, chronic medical condition or autism. Youth participated in 2 × 2 randomized controlled trials, in which they received Ω3 or placebo (PBO) and psychoeducational psychotherapy (PEP) or active monitoring (AM). Participants and study staff (including independent interviewers) were masked to Ω3/PBO allocation. Besides the masked independent interviewers, one coprincipal investigator (Co-PI) was fully masked to both conditions and completed all consensus conference ratings postrandomization. At the endpoint assessment or last completed interview, interviewers and the masked Co-PI guessed whether each child was assigned to Ω3 or PBO and to PEP or AM. Masking failure was calculated using the degree of correct guesses above chance level using binomial tests across all participants for Ω3 versus PBO and PEP versus AM. For all guessers, Ω3 allocation was guessed correctly approximately half the time (50%–52.5%). Rates of correct guessing were higher for PEP, but only the interviewer guesses were correct significantly more often (58.5%–68.7%) than chance. Reporting of masking success should be an essential element of RCTs. Psychotherapy is generally more difficult to mask, but with attentive masking procedures reasonable masking can be achieved.  相似文献   
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The aim of this study was to investigate the role of the nitric oxide (NO) system in ovarian function, by determining if arginine (Arg) supplementation impacts follicle number, cell proliferation, and expression of the NO system members in nutritionally compromised ewes. Ewes were randomly assigned into maintenance (C, 100% requirements), excess (O; 2xC), or restricted (U; 0.6xC) diets 8 weeks prior to Arg treatment. Ewes were individually fed twice daily with pelleted diets. Ewes from each nutritional group were randomly assigned to one of two treatments: saline or Arg, which was initiated on day 0 of the estrous cycle and administered 3 times per day. Ovaries were collected at the early-luteal, mid-luteal and late-luteal/follicular phases of the estrous cycle to determine 1) the number of surface follicles, 2) follicle cell proliferation marked by Ki67 protein expression, and 3) expression of endothelial nitric oxide (eNOS; NOS3) and soluble guanylyl cyclase beta (sGC; GUCY1B3) protein and mRNA in granulosa (G) and theca (T) layers using immunohistochemistry followed by image analysis and qPCR, respectively. During nutritional treatment, C maintained body weight, O gained 6±1.2 kg, and U lost 14±1.3 kg. Our data show that: 1) Ki67 was expressed in all ovarian compartments, eNOS protein was detected in blood vessels of T and stroma, and sGC protein was detected in T cells, and blood vessels of T layer and other ovarian compartments; 2) plane of nutrition affected the number of surface follicles, and thus folliculogenesis, cell proliferation in the T layer, eNOS and sGC protein expression in T, and NOS3 and GUCY1B3 mRNA expression in G; 3) Arg treatment affected cell proliferation in G and T, eNOS and sGC protein expression in T, mRNA expression of NOS3 in T in all groups, and GUCY1B3 in G depending on the stage of the estrous cycle; and 4) G and T cell proliferation, and expression of eNOS and sGC protein in T was affected by the stage of the estrous cycle. Our data demonstrated that plane of nutrition and Arg are involved in the regulation of follicular functions in non-pregnant sheep.  相似文献   
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