Production of a chiral alcohol, 1-(3,4-dihydroxyphenyl) ethanol, by mushroom tyrosinase.

1-(3,4-Dihydroxyphenyl) ethanol was produced biocatalytically for the first time using mushroom tyrosinase. 4-Ethylphenol at 1 mM was consumed over 12 min giving 0.23 mM 4-ethylcatechol and 0.36 mM (R/S)-1-(3,4-dihydroxyphenyl) ethanol (ee 0.5 %). Mushroom tyrosinase consumed 4-ethylphenol at 6.7 µmol min(-1) mg protein(-1) while the rates of formation of 4-ethylcatechol and 1-(3,4-dihydroxyphenyl) ethanol were 1.1 and 1.9 µmol min(-1) mg protein(-1). Addition of the ascorbic acid, as a reducing agent to biotransformation reactions, increased 4-ethylcatechol formation by 340 %. However, accumulation of 1-(3,4-dihydroxyphenyl) ethanol was not observed in the presence of ascorbic acid. While the 1-(3,4-dihydroxyphenyl) ethanol was racemic, it is the first chiral product produced by tyrosinase starting from a non-chiral substrate.

Antistaphylococcal nanocomposite films based on enzyme-nanotube conjugates.

Infection with antibiotic-resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) is one of the primary causes of hospitalizations and deaths. To address this issue, we have designed antimicrobial coatings incorporating carbon nanotube-enzyme conjugates that are highly effective against antibiotic-resistant pathogens. Specifically, we incorporated conjugates of carbon nanotubes with lysostaphin, a cell wall degrading enzyme, into films to impart bactericidal properties against Staphylococcus aureus and Staphylococcus epidermidis. We fabricated and characterized nanocomposites containing different conjugate formulations and enzyme loadings. These enzyme-based composites were highly efficient in killing MRSA (>99% within 2 h) without release of the enzyme into solution. Additionally, these films were reusable and stable under dry storage conditions for a month. Such enzyme-based film formulations may be used to prevent growth of pathogenic and antibiotic-resistant microorganisms on various common surfaces in hospital settings. Polymer and paint films containing such antimicrobial conjugates, in particular, could be advantageous to prevent risk of staphylococcal-specific infection and biofouling.

Expanding the Scope of Biocatalysis: Oxidative Biotransformations on Solid-Supported Substrates.

Oxidative biocatalytic reactions were performed on solid-supported substrates, thus expanding the repertoire of biotransformations that can be carried out on the solid phase. Various phenylacetic and benzoic acid analogs were attached to controlled pore glass beads via an enzyme-cleavable linker. Reactions catalyzed by peroxidases (soybean and chloro), tyrosinase, and alcohol oxidase/dehydrogenase gave a range of products, including oligophenols, halogenated aromatics, catechols, and aryl aldehydes. The resulting products were recovered following cleavage from the beads using α-chymotrypsin to selectively hydrolyze a chemically non-labile amide linkage. Controlled pore glass (CPG) modified with a polyethylene glycol (PEG) linker afforded substantially higher product yields than non-PEGylated CPG or non-swellable polymeric resins. This work represents the first attempt to combine solid-phase oxidative biotransformations with subsequent protease-catalyzed cleavage, and serves to further expand the use of biocatalysis in synthetic and medicinal chemistry.

Expert Canadian consensus suggestions on the rational, clinical use of ziprasidone in the treatment of schizophrenia and related psychotic disorders.

Many atypical antipsychotic medications are becoming available for clinical use. Ziprasidone is a recent addition to this group and is expected to become available for clinical use in Canada in 2005. Ziprasidone has some significant differences compared with other atypicals currently available in Canada. Clinicians need to understand the benefits and risks associated with each of the antipsychotic medications available for the treatment of schizophrenia and related psychotic disorders to ensure their most appropriate utilization. At the suggestion of Professor Stan Kutcher (chair) and as part of an ongoing commitment to provide independent education pertaining to the utility of new psychotropic compounds to health professionals, a panel of Canadian experts in the treatment of schizophrenia spectrum disorders was convened to provide consensus suggestions for the appropriate clinical use of ziprasidone. The consultations regarding the development of these recommendations were organized by Brainworks International (BWI) with arms-length funding from Pfizer Canada. This paper describes the experts' consensus views on the efficacy and safety of ziprasidone, their suggestions on which patients may be suitable for ziprasidone treatment, and how to initiate treatment (including how to switch from other antipsychotic medications), manage side effects, and monitor patients in long-term therapy. These suggestions are those of the authors only and are not endorsed by or necessarily reflect the opinions of BWI or Pfizer Canada.

The Kutcher Generalized Social Anxiety Disorder Scale for Adolescents: assessment of its evaluative properties over the course of a 16-week pediatric psychopharmacotherapy trial.

OBJECTIVE: This study investigated the psychometric properties of a new clinician-rated scale designed to assess the severity of social phobia and measure treatment outcome in adolescents: the Kutcher Generalized Social Anxiety Disorder Scale for Adolescents (K-GSADS-A). METHODS: Two hundred fifty-one (251) adolescents (11-17 years; mean age 14.2 years) with DSM-IV social phobia enrolled in a multicenter, 16-week, double-blind, placebo-controlled study of paroxetine. Efficacy assessments were conducted at baseline and at weeks 4, 8, 12, and 16 with the K-GSADS-A, three other clinician-rated scales (including the Clinical Global Impression of Severity scale), and a self-rated social phobia scale. Additionally, the Clinical Global Impression of Improvement scale was administered at each postbaseline assessment, and the Children's Depression Rating Scale-Revised was administered at baseline and at week 16. These data were used to assess the internal consistency, convergent and divergent validity, and sensitivity to change of the K-GSADS-A. RESULTS: The internal consistency of the K-GSADS-A was adequate, and supportive evidence was obtained for its convergent validity with other severity measures, and its divergent validity with respect to depression. The K-GSADS-A also demonstrated good sensitivity to changes in severity. CONCLUSIONS: These results suggest that the K-GSADS-A is a valid measure of treatment outcome in adolescents with DSM-IV social phobia.

The feasibility of a mental health curriculum in elementary school.

OBJECTIVE: To establish the feasibility and short-term impact of implementing a novel curriculum in a linguistically and geographically isolated francophone community to enhance elementary schoolchildren's (Grades 1 to 7; n = 158) knowledge and attitudes regarding mental health. METHODS: The project team developed a curriculum that covered expected emotional development, depression, anxiety disorders, and attention-deficit hyperactivity disorder to be delivered by the school's usual teachers. Committee members led focused discussions (Grades 1 to 7) and administered evaluation questionnaires (Grades 4 to 7) surveying students' knowledge and attitudes before and after implementation. RESULTS: Teachers were enthusiastic about the project. Parents were initially skeptical, but post hoc interventions by school staff secured participation consent for 98% of the students. Baseline data (Grades 4 to 7) revealed little knowledge and some negative attitudes regarding mental illnesses; postprogram data indicated improved knowledge and suggested improved attitudes. CONCLUSIONS: The project was made feasible by the high degree of involvement of local community members. Children's (Grades 4 to 7) mental health awareness and understanding was enhanced by the curriculum. Effects on help-seeking behaviour and case identification have yet to be assessed.

International consensus statement on attention-deficit/hyperactivity disorder (ADHD) and disruptive behaviour disorders (DBDs): clinical implications and treatment practice suggestions.

Researchers and clinicians worldwide share concerns that many youngsters with attention-deficit/hyperactivity disorder (ADHD) and/or disruptive behaviour disorders (DBDs) do not receive appropriate treatment despite availability of effective therapies. At the request of Johnson and Johnson (sponsor), 11 international experts in child and adolescent psychiatry were selected by Professor Stan Kutcher (chair) to address these concerns. This paper describes the experts' consensus conclusions, including treatment practice suggestions for physicians involved in the early treatment of youngsters with ADHD (or hyperkinetic disorder, in countries preferring this classification) and/or DBDs internationally: suggested first-line treatment for ADHD without comorbidity is psychostimulant medication aided by psychosocial intervention. For ADHD with comorbid conduct disorder (CD), psychosocial intervention combined with pharmacotherapy is suggested. For primary CD, suggested first-line treatment is psychosocial intervention, with pharmacotherapy considered as an 'add-on' when aggression/impulsivity is marked and persistent. Pharmacotherapy requires careful titration; full-day coverage is the suggested goal. Regular long-term follow-up is recommended.

The Kutcher Adolescent Depression Scale: assessment of its evaluative properties over the course of an 8-week pediatric pharmacotherapy trial.

OBJECTIVE: Self-report instruments commonly used to assess depression in adolescents have limited or unknown psychometric properties in this age group. We report the evaluative properties of the Kutcher Adolescent Depression Scale (KADS), a self-report scale designed specifically for identifying depressed adolescents and for monitoring symptom severity over time. METHODS: One hundred and six adolescents with major depression disorder (MDD) enrolled in an 8-week, double-blind, placebo-controlled study of paroxetine. Efficacy assessments were conducted on days 0 (baseline), 7, 14, 21, 28, 42, and 56 using the self-rated KADS and the clinician-rated Children's Depression Rating Scale-Revised (CDRS-R), Clinical Global Impression (CGI) of severity, and Global Assessment of Functioning (GAF) scale. The data were initially examined to establish which of the 16 KADS items showed greatest sensitivity to change. Subsequent analyses then compared the evaluative properties of three versions of the KADS: the full-length KADS, a six-item subscale previously established as a screening tool, and an 11-item subscale optimized for sensitivity to change. RESULTS: Within-subject correlations among subjects' KADS scores and their clinician-rated scale scores showed that clinician-rated changes in severity were significantly better corroborated by the 11-item KADS (mean correlations with the CDRS-R, CGI, and GAF: r = 0.69, 0.60, and -0.70, respectively) than by the six-item KADS (r = 0.62, 0.56, and -0.63, respectively) and at least as well corroborated as by the full-length KADS (r = 0.64, 0.56, and -0.67, respectively). Furthermore, in terms of mean percentage change in scores from day 0 to day 56, the 11-item KADS (59%) significantly outperformed the full-length KADS (46%) and all three clinician-rated scales (43%, 37%, and 29%, respectively) and at least matched the performance of the six-item KADS (56%). CONCLUSIONS: These results suggest that the 11-item self-rated KADS is a sensitive measure of treatment outcome in adolescents diagnosed with MDD.

Diagnosis and measurement of anxiety disorder in adolescents: a review of commonly used instruments.

As part of a comprehensive review of clinical research tools used in adolescent psychiatric disorders, a survey of 200 recent studies of adolescent anxiety (publication dates of December 1994 to May 2001) identified 70 different diagnostic and symptom measurement instruments. The design features and psychometric properties of the 15 most commonly used instruments were reviewed, and their strengths and weaknesses were evaluated. The conclusions arising from this review are: (1) too many different instruments are being used by investigators; (2) more than 20% of studies did not report the use of developmentally appropriate (i.e., child/adolescent-specific) diagnostic instruments; (3) another 15% of these studies relied on diagnostic instruments that demonstrate substantial weaknesses in reliability and validity; (4) the concordance between anxiety disorder diagnoses from different interview schedules is unknown; (5) the relative validity of diagnoses and ratings of anxiety severity based on information yielded by parents versus information yielded by adolescents is unclear; (6) clinician-rated symptom severity scales specific to anxiety disorder are rarely utilized; (7) the most commonly used self-report measures discriminate poorly between anxiety and depression, and their items are not indexed to specific anxiety disorders; and (8) some newer self-report anxiety instruments discriminate well between anxiety and depression and have diagnostic validity for specific anxiety disorders.

Screening for adolescent depression: comparison of the Kutcher Adolescent Depression Scale with the Beck depression inventory.

Self-report instruments commonly used to assess depression in adolescents have limited or unknown reliability and validity in this age group. We describe a new self-report scale, the Kutcher Adolescent Depression Scale (KADS), designed specifically to diagnose and assess the severity of adolescent depression. This report compares the diagnostic validity of the full 16-item instrument, brief versions of it, and the Beck Depression Inventory (BDI) against the criteria for major depressive episode (MDE) from the Mini International Neuropsychiatric Interview (MINI). Some 309 of 1,712 grade 7 to grade 12 students who completed the BDI had scores that exceeded 15. All were invited for further assessment, of whom 161 agreed to assessment by the KADS, the BDI again, and a MINI diagnostic interview for MDE. Receiver operating characteristic (ROC) curve analysis was used to determine which KADS items best identified subjects experiencing an MDE. Further ROC curve analyses established that the overall diagnostic ability of a six-item subscale of the KADS was at least as good as that of the BDI and was better than that of the full-length KADS. Used with a cutoff score of 6, the six-item KADS achieved sensitivity and specificity rates of 92% and 71%, respectively-a combination not achieved by other self-report instruments. The six-item KADS may prove to be an efficient and effective means of ruling out MDE in adolescents.