Streamlined screening of extracellularly expressed PETase libraries for improved polyethylene terephthalate degradation.

Enzyme-mediated polyethylene terephthalate (PET) depolymerization has recently emerged as a sustainable solution for PET recycling. Towards an industrial-scale implementation of this technology, various strategies are being explored to enhance PET depolymerization (PETase) activity and improve enzyme stability, expression, and purification processes. Recently, rational engineering of a known PET hydrolase (LCC-leaf compost cutinase) has resulted in the isolation of a variant harboring four-point mutations (LCC-ICCG), presenting increased PETase activity and thermal stability. Here, we revealed the enzyme's natural extracellular expression and used it to efficiently screen error-prone genetic libraries based on LCC-ICCG for enhanced activity toward consumer-grade PET. Following multiple rounds of mutagenesis and screening, we successfully isolated variants that exhibited up to a 60% increase in PETase activity. Among other mutations, the improved variants showed a histidine to tyrosine substitution at position 218, a residue known to be involved in substrate binding and stabilization. Introducing H218Y mutation on the background of LCC-ICCG (named here LCC-ICCG/H218Y) resulted in a similar level of activity improvement. Analysis of the solved structure of LCC-ICCG/H218Y compared to other known PETases featuring different amino acids at the equivalent position suggests that H218Y substitution promotes enhanced PETase activity. The expression and screening processes developed in this study can be further used to optimize additional enzymatic parameters crucial for efficient enzymatic degradation of consumer-grade PET.

Parallel-group placebo-controlled trial of testosterone gel in men with major depressive disorder displaying an incomplete response to standard antidepressant treatment.

Exogenous testosterone therapy has psychotropic effects and has been proposed as an antidepressant augmentation strategy for depressed men. We sought to assess the antidepressant effects of testosterone augmentation of a serotonergic antidepressant in depressed, hypogonadal men. For this study, we recruited 100 medically healthy adult men with major depressive disorder showing partial response or no response to an adequate serotonergic antidepressant trial during the current episode and a screening total testosterone level of 350 ng/dL or lower. We randomized these men to receive testosterone gel or placebo gel in addition to their existing antidepressant regimen. The primary outcome measure was the Hamilton Depression Rating Scale (HDRS) score. Secondary measures included the Montgomery-Asberg Depression Rating Scale, the Clinical Global Impression Scale, and the Quality of Life Scale. Our primary analysis, using a mixed effects linear regression model to compare rate of change of scores between groups on the outcome measures, failed to show a significant difference between groups (mean [95% confidence interval] 6-week change in HDRS for testosterone vs placebo, -0.4 [-2.6 to 1.8]). However, in one exploratory analysis of treatment responders, we found a possible trend in favor of testosterone on the HDRS. Our findings, combined with the conflicting data from earlier smaller studies, suggest that testosterone is not generally effective for depressed men. The possibility remains that testosterone might benefit a particular subgroup of depressed men, but if so, the characteristics of this subgroup would still need to be established.

Effects of testosterone replacement in middle-aged men with dysthymia: a randomized, placebo-controlled clinical trial.

Mid-life onset male dysthymic disorder (DD) seems to be a distinct clinical condition with limited therapeutic options. Testosterone replacement is mood-enhancing and has been proposed as an antidepressant therapy, though this strategy has received limited systematic study. We therefore conducted a six-week double-blind placebo-controlled clinical trial in 23 men with DD and with low or low-normal testosterone (T) level (i.e, screening total serum testosterone <350 ng/dL). Enrolled men were randomized to receive intramuscular injections of 200 mg of testosterone cypionate or placebo every 10 days. The primary outcome measures were the Clinical Global Impression (CGI) improvement score and the 21-item Hamilton Depression Rating Scale (HDRS) score.Twenty-three patients were randomized. The mean (SD) age of the enrolled patients was 50.6 (7.0) years and that of total testosterone level was 339 (93) ng/dL. The median duration of the current dysthymic episode was 3.6 (2.3) years, and the mean (SD) HDRS was 14.0 (2.9). After the intervention, the mean HDRS score decreased significantly more in the testosterone group (7.46 [4.56]) than in the placebo group (1.8 [4.13], t21 = -3.07, P = 0.006). Remission, defined as a CGI improvement score of 1 or 2 and a final HDRS score lower than 8, was achieved by 7 (53.8%) of 13 in the testosterone group and 1 (10%) of 10 in the placebo group (P = 0.03). Testosterone replacement may be an effective antidepressant strategy for late-onset male dysthymia.

An open-label pilot study to evaluate the efficacy of sildenafil citrate in middle-aged men with late-onset dysthymia.

Late onset dysthymic disorder (DD) in middle-aged and elderly men responds poorly to established antidepressants. Previous studies noted an improvement in mood accompanying sildenafil citrate treatment for erectile dysfunction. We sought to evaluate whether sildenafil's mood effects were independent of the effect on erectile function. A 6-week open label study was conducted with 20 male participants, aged 41-60 who were diagnosed with DD and who had normal erectile function. Participants were treated with sildenafil citrate 25 mg per day for 6 weeks. The primary outcome measure was the 21-item Hamilton Depression Rating Scale. Depressive and sexual symptoms were also evaluated using self-report questionnaires. Treatment with sildenafil resulted in a significant reduction in Hamilton Depression Rating Scale mean scores: from 14.61 +/- 3.5 at baseline to 6.39 +/- 5.13 at end of study (F(3,51) = 32.52, p

[Legal aspects of the psychiatric treatment of minors].

This article deals with the involvement of the law in the psychiatric treatment of minors through the directives it gives with regards to examination, diagnosis, treatment and hospitalization of minors. In recent years changes have been made in the law dealing with these issues. These were set out in the 1995 amendments to two laws: "The Law of the Treatment and Supervision of Minors" and "the Law of the Treatment of the Mentally Ill". The amendments include changes in the procedural processes as well as the introduction of concepts which did not exist in the previous laws. Since these amendments have begun to be put into practice, the therapeutic system has discovered that problems have arisen in two areas--the conceptual and the practical--of the instructions of the new laws. These problems arise out of the difficulty in understanding what the laws actually say, difficulties in executing the laws, and a special clumsiness which causes it to miss its objective through the insistence on systems of control the likes of which are not found in any other branch of medicine. This article will discuss the above-mentioned amendments to the law with two aims in mind: to present an overview and clarification of a complex and complicated law with which a large part of the public is not competently apprised; and to present the limitations of this law and our comments about it.

Effectiveness of sildenafil in treating erectile dysfunction in PTSD patients: a double-blind, placebo-controlled crossover study.

OBJECTIVE: Post Traumatic Stress Disorder (PTSD) is known to be associated with Erectile Dysfunction (ED). Sildenafil citrate was shown to be effective treatment for ED among different clinical populations. However, to date, no placebo-controlled trial has assessed sildenafil's effectiveness for treating ED in PTSD patients. The goal of the present study was to address this question using a double-blind placebo controlled crossover design. METHODS: A four-week double-blind crossover trial of sildenafil (50 mg up to 100 mg per usage) versus placebo was conducted on 21 outpatients diagnosed with chronic PTSD accompanied by ED. Erectile function was assessed biweekly using the International Inventory of Erectile Function (IIEF). Depressive symptoms, PTSD symptoms and subjective well-being scores were assessed as well. RESULTS: Analysis of IIEF scores revealed a main effect of treatment phase (E = 33.361, df =2, P < 0.000). Pairwise comparisons showed that sildenafil IIEF scores (mean = 45.19 +/- 15.05) were significantly higher compared to baseline scores (mean = 20.00 +/- 12.32, P = 0.000) and placebo scores (mean = 33.04 +/- 12.99). Compared to placebo, a significant improvement was also observed during the sildenafil phase in erectile function, orgasmic function and sexual desire. There was no significant change in depression, PTSD symptoms or subjective well-being. CONCLUSION: The results of this study suggest that sildenafil citrate treatment for ED in PTSD patients was accompanied with improvement of ED symptoms and was found to be significantly better than placebo. Nevertheless, this effect should be considered marginal since patients still meet the criteria of ED after treatment. Larger, parallel group studies are warranted.