Forest Research Institute

About: Forest Research Institute is a facility organization based out in Dehra Dūn, India. It is known for research contribution in the topics: Population & Forest management. The organization has 5320 authors who have published 7625 publications receiving 185876 citations.

Double-Blind Comparison of Escitalopram and Duloxetine in the Acute Treatment of Major Depressive Disorder

Abstract: Background and objective: Escitalopram is the most selective serotonin reuptake inhibitor antidepressant; in contrast, duloxetine inhibits both serotonin and norepinephrine reuptake. Double-blind comparison studies may help guide treatment decisions by revealing the relative benefits of different therapeutic approaches. This study evaluated the efficacy and safety of escitalopram versus duloxetine in the acute treatment of patients with moderate to severe major depressive disorder. Methods: A 1-week, single-blind, placebo lead-in period followed by an 8-week, randomised, double-blind, multicentre, parallel-group comparison was conducted from 20 April 2005 to 10 March 2006 in independent psychiatric research facilities with principal investigators who were board certified in psychiatry. A total of 278 outpatients of 382 patients screened with Diagnostic and Statistical Manual of Mental Disorders (4th edition)-diagnosed major depressive disorder (Montgomery-Asberg Depression Rating Scale [MADRS] total score ≥26) were randomised to the two treatment groups. Eight patients received no medication and were excluded from the safety group. Patients were treated with either escitalopram 10–20 mg/day (fixed at 10 mg/day for the first 4 weeks) or duloxetine 60 mg/day. The primary efficacy variable was change from baseline at week 8 in MADRS total score using the last observation carried forward (LOCF) approach. Efficacy, safety and tolerability measures were prospectively defined in the statistical analysis plan prior to study initiation unless otherwise specifically noted as conducted post hoc. Results: A significantly greater proportion of escitalopram-treated patients completed the 8-week study compared with duloxetine-treated patients (87% vs 69%, respectively; p < 0.01). Mean baseline MADRS total scores were 31.0 for the escitalopram group and 31.6 for the duloxetine group. At week 8, escitalopram treatment resulted in significantly greater improvement compared with duloxetine on the prospectively defined primary efficacy endpoint of mean change from baseline in MADRS total score using the LOCF approach (least-squares mean difference [LSMD] −2.42; 95% CI −4.73, −0.11; p < 0.05). There was no difference between treatment groups in the observed cases (OC) analysis (LSMD −0.32; 95% CI −2.71, 2.07; p = 0.79). Significantly fewer escitalopram-treated patients discontinued because of adverse events compared with duloxetine (2% vs 13%, respectively; p < 0.01). Conclusion: These findings suggest that escitalopram is better tolerated and at least as effective as the serotonin-norepinephrine reuptake inhibitor duloxetine in the treatment of major depressive disorder.

Fungal succession in sapwood of Norway spruce infested by the bark beetle Ips typographus

Abstract: Fungal invasion of Norway spruce sapwood was investigated during a period of 130 weeks fol-lowing attack by the spruce bark beetle Ips typographus. Heavy beetle attack tended to overwhelm the trees quickly and no secondary resinosis was produced. Nonetheless, fungal penetration in the sapwood was initiated only slowly, although it accelerated during the fourth week after attack. Typically the leading edge of fungal penetration was a few millimeters in advance of the visible blue-stain during the sapwood colonization. Fungi invaded the sapwood in a successional pattern with the most pathogenic species Ophiostoma polonicum first, followed by other beetle-transmitted Ophiostoma and Graphium species. The later succession was probably influenced by sapwood moisture. Strong decaying white-rotters invaded near the base of the trees, where sapwood moisture remained favourable, while cf. Trichoderma viride dominated in the drier parts or the trees.

Forest development in canopy gaps in old-growth beech (Nothofagus) forests, New Zealand

Abstract: Tree size and age structures, treefall and canopy gap characteristics, and regeneration responses to treefalls were compared for three stands of old-growth beech (Notho- fagus) forest dominated by N. fusca and N. menziesii on the South Island, New Zealand. Treefall gaps (up to 1000 m2) were most often caused by standing trees killed by drought and/or insect attack, or by trees snapped by wind. The causes of gap formation and the size and age distributions of treefall gaps varied between localities because of spatial and temporal differences in the histories of disturbance. At Fergies Bush where drought-related dieback had produced many large gaps with standing dead trees, gaps were generally young. Con- versely, at Station Creek, small, old gaps formed by bolesnap dominated the disturbance regime. At Rough Creek, gaps of all ages and sizes were found along with an almost complete fern cover, and abundant shrubs and occasional subcanopy hardwood trees. Although overall patterns of regeneration were unrelated to differences in gap size, the relative abundance of N. fusca and N. menziesii varied between localities according to the seemingly minor differences in forest structure and disturb- ance history described above. Interpretations of regeneration response to gap parameters, therefore, need to account for differences in disturbance history between sites. Differences in the disturbance history between localities will also influ- ence rates of gap closure, and because closure rates are used to estimate forest turnover times, meaningful comparisons of disturbance regimes for different forest types can only be made if this intersite variability is addressed.

Combined Ips/Ceratocystis attack on Norway spruce, and defensive mechanisms of the trees1

Abstract: The spruce bark beetle, Ips typographus, infects Norway spruce trees with blue-stain fungi, amongst which several species of Ceratocystis are found. Artificial inoculation of healthy trees with C. polonica caused in several cases increased water stress of the trees, and complete sapwood staining. The defences of spruce against Ips/Ceratocystis attack appear to depend on 1. the output of constitutive resin from severed resin ducts, and 2. accumulation of secondary resin around the attack sites. Our preliminary studies indicate that the amount of both types of resin may vary considerably between trees, as well as from place to place on the same tree. A dose/response experiment based on artificial inoculation of C. polonica indicated that at a certain dose (i.e. number of infections per unit area), the accumulation of secondary resin decreased, and the fungus was able to overcome the host defence. Zusammenfassung Kombinierter Befall von Ips und Ceratocystis an Fichte und Abwehrmechanismen der Baume Der Fichtenborkenkafer Ips typographus infiziert seine Wirtsbaume mit Blauepilzen, insbesondere verschiedene Arten von Ceratocystis. Kunstliche Infektion gesunder Fichten mit C. polonica fuhrte in mehreren Fallen zu einem gestorten Wasserhaushalt der Baume und vollstandiger Verfarbung des Splintholzes. Die Abwehrmechanismen der Fichte gegen Ips/Ceratocystis-Befall beruhen offenbar auf 1. der Menge des Harzaustritts aus verletztem Gewebe und 2. der Anreicherung von Wundharz im Bereich der Befallsstellen. Unsere Vorversuche weisen darauf hin, das die Menge von Primar- und Sekundarharz von Baum zu Baum und auch innerhalb eines Baumes sehr verschieden sein kann. Ein quantitativer Versuch zur kunstlichen Infektion von Fichte mit C. polonica fuhrte ab einer bestimmten Infektionsstarke zur Abnahme der Wundharzproduktion, so das der Pilz den Wirt erfolgreich besiedeln konnte.