Alterations in the odor profile of plants in cultivar mixtures affect aphid host-location behavior.

The effect of cultivar mixtures on aphid control is attributed to the masking or alteration of host-preferred cultivar odor cues. However, the underlying physiological mechanism remains unclear. This study assessed alterations in the volatile emissions of wheat cultivars grown together (Florence-Aurora and Forment; Florence-Aurora and Montcada) and the consequences for the olfactory preference of aphids. Volatile organic compounds were collected from wheat plants grown in a laboratory under mixed or monoculture conditions and subsequently analyzed. The odor profiles of Florence-Aurora and Montcada were indistinguishable from each other. However, the odors of Florence-Aurora and Forment grown in monocultures differed significantly from those emitted by their mixture. The Florence-Aurora and Forment mixture induced plant physiological responses that affected the emission of single volatile compounds and, consequently, altered volatile organic compound ratios. English grain aphids (Sitobion avenae) were less attracted to the odors of Florence-Aurora and Forment when grown as a mixture than the combination of the odors from Florence-Aurora and Forment monocultures. Moreover, aphids preferred clean air over the odor from the Florence-Aurora and Forment mixture but preferred the odor from the Florence-Aurora and Montcada mixture over clean air. This study highlights the beneficial effects of intraspecific plant diversity on aphid control by altering plant odors in response to plant-plant interactions. The emission of less attractive odor cues consequently affects plant-aphid interactions; hence, less attractive odors are likely to impair aphid host-locating behavior. This effect was exclusive to certain cultivar mixtures, which supports the "right neighbor" concept.

Antiaggressive effect of cyproterone versus haloperidol in Alzheimer's disease: a randomized double-blind pilot study.

OBJECTIVE: Alzheimer's disease (AD) is commonly accompanied by aggressive behavior. In the elderly, effective and safe antiaggressive treatment is lacking. Risks of antipsychotics in this population demand therapeutic alternatives. This randomized, double-blind, pilot trial examined the efficacy and safety of cyproterone in the treatment of agitated AD. METHOD: The subjects were 27 elderly patients referred to the University Hospital of Guadalajara Psychogeriatric Clinic diagnosed with AD and associated aggressive behavior (mean Staff Observation Aggression Scale [SOAS] score >or=2). Each patient underwent a 15-day washout for psychotropics and then was randomly assigned to receive stable doses of either cyproterone (100 mg/day) or haloperidol (2 mg/day) for 90 days. The primary outcome measure was the SOAS score. This trial was conducted between October 27, 1993, and March 24, 1998. RESULTS: Of the 27 patients, 19 (70.4%) were women, and the mean age was 80.7 years. The trial was completed by 24 (88.9%) of the subjects (13 in the cyproterone group and 11 in the haloperidol group for 90 days). Three patients (11.1%) dropped out, all after adverse effects in the haloperidol group. Baseline aggression level in the sample was mild (mean SOAS score of 4.48 [SD = 2.04]). Efficacy analyses for all intent-to-treat patients showed that 9 (69.2%) in the cyproterone group achieved complete elimination of aggression at endpoint, in contrast to 2 patients (14.2%) in the haloperidol group (p = .012). Ten patients (71.4%) taking haloperidol had adverse events, compared with 4 (30.7%) taking cyproterone (p = .035). CONCLUSION: Cyproterone showed significantly better efficacy and safety than haloperidol in controlling mild aggression associated with AD. Additional research is needed to confirm if these results can be ratified in a larger study and generalized to patients whose aggression is more severe.

Efficacy of venlafaxine in major depression resistant to selective serotonin reuptake inhibitors.

INTRODUCTION: Some studies suggest that venlafaxine, due to its pharmacodynamic characteristics, could be an effective drug in depression, resistant to other antidepressive agents. This investigation explores the efficacy and tolerability of venlafaxine in major depression, resistant to a selective serotonin reuptake inhibitor (SSRI). METHODS: A multicenter naturalistic study was performed during 6 months and included those patients diagnosed of major depression according to the criteria of DSM-IV who had a minimum score of 18 on the Hamilton Depression Rating Scale (HAM-D) and who had not responded to previous treatment with a SSRI at therapeutic doses for a minimum of 4 weeks. The assessment of efficacy was performed with the HAM-D scale, the Montgomery-Asberg Depression Rating Scale (MADRS), the Hamilton Anxiety Rating Scale (HAM-A) and the Global Clinical Impression (GCI). Tolerability was evaluated by recording the adverse reactions and with the GCI score on overall drug tolerability. RESULTS: A total of 69 patients, of which 59 were evaluable for efficacy (they had fulfilled at least 4 weeks of treatment), were included. About 81% of all of them obtained a reduction of at least 50% in the HAM-D, 74% were considered as "quite improved" or "very improved" in the GCI and 69% met both criteria. The mean dose of venlafaxine used was 170.4 (S.D.=43.8) mg. Of the 21 patients who did not complete the 6 months of treatment, 3 were due to lack of efficacy, 6 due to adverse effects and 12 for other reasons. About 89.2% of side effects were considered as mild or moderate. CONCLUSION: The results of our study support the efficacy and tolerability of venlafaxine in patients suffering from depression who have not responded to SSRI treatment.

[Validation of the Spanish versions of the Montgomery-Asberg depression and Hamilton anxiety rating scales]. / Validación de las versiones en español de la Montgomery-Asberg Depression Rating Scale y la Hamilton Anxiety Rating Scale para la evaluación de la depresión y de la ansiedad.

BACKGROUND: Affective and anxiety disorders (AfD & AnD) are the most common psychiatric diseases in the general population. This study's aim was to assess for the first time the psychometric properties of the Spanish translated versions of the Montgomery-Asberg Depression Rating Scale (MADRS) and the Hamilton Anxiety Rating Scale (HARS), which are widely used both in medical care and clinical research. PATIENTS AND METHOD: A cohort, observational, prospective and multicentre study was conducted in clinically stable or unstable patients with AfD and AnD. The scales were administered at baseline and in a second study visit one week or 2 months later (to stable or unstable patients, respectively). The internal consistency, temporary stability, inter-raters reliability, factorial structure, convergent and discriminant validity, and sensitivity to change were all assessed for both scales. RESULTS: One hundred and eight AfD patients and 106 AnD patients were recruited in 10 psychiatry care centres from a wide geographical distribution. Both scales showed adequate properties in terms of: a) discriminant validity (MADRS/HARS-Clinical Global Impression: p < 0.001); b) convergent validity (MADRS-Hamilton Depression Rating Scale: p < 0.05 and 0.01; MADRS/HARS-EuroQoL 5D: p < 0.05; HARS-State Trait Anxiety Inventory: p < 0.05); c) internal consistency (Cronbach's alpha: MADRS = 0.88; HARS = 0.89); d) test-retest and inter-raters reliability (intraclass correlation coefficient: MADRS = 0.94 and 0.98, respectively; HARS = 0.92 and 0.92), and, e) sensitivity to change (effect size: MADRS = 2.05; HARS = 1.36). CONCLUSIONS: Spanish versions of MADRS and HARS scales showed good psychometric properties, similar to those of the original scales. Therefore, these scales are suitable for use in clinical practice and research in Spain.