Beta-ionone is a functional plant volatile that attracts the parasitic wasp,Microplitis pallidipes

BioControl - The effects of plant volatiles on parasitoids are important with regards to the tri-trophic interactions among host plants, insect herbivores, and their natural enemies. However, the...     

Do lianas shape ant communities in an early successional tropical forest?

Almost half of lowland tropical forests are at various stages of regeneration following deforestation or fragmentation. Changes in tree communities along successional gradients have predictable bottom‐up effects on consumers. Liana (woody vine) assemblages also change with succession, but their effects on animal succession remain unexplored. Here we used a large‐scale liana removal experiment across a forest successional chronosequence (7–31 years) to determine the importance of lianas to ant community structure. We conducted 1,088 surveys of ants foraging on and living in trees using tree trunk baiting and hand‐collecting techniques at 34 paired forest plots, half of which had all lianas removed. Ant species composition, β‐diversity, and species richness were not affected by liana removal; however, ant species co‐occurrence (the coexistence of two or more species in a single tree) was more frequent in control plots, where lianas were present, versus removal plots. Forest stand age had a larger effect on ant community structure than the presence of lianas. Mean ant species richness in a forest plot increased by ca. 10% with increasing forest age across the 31‐year chronosequence. Ant surveys from forest >20 years old included more canopy specialists and fewer ground‐nesting ant species versus those from forests <20 years old. Consequently, lianas had a minimal effect on arboreal ant communities in this early successional forest, where rapidly changing tree community structure was more important to ant species richness and composition.     

Mechanism of Cross-talk between H2B Ubiquitination and H3 Methylation by Dot1L

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Biofertilizing Effect of Chlorella sorokiniana Suspensions on Wheat Growth

Journal of Plant Growth Regulation - The potential of microalgae as a biofertilizer in agriculture is increasingly recognized. We studied the effect of applications of Chlorella on growth of wheat...     

Clinical applications of dendritic cell vaccination in the treatment of cancer

Dendritic cell (DC) immunotherapy has shown significant promise in animal studies as a potential treatment for cancer. Its application in the clinic depends on the results of human trials. Here, we review the published clinical trials of cancer immunotherapy using exogenously antigen-exposed DCs. We begin with a short review of general properties and considerations in the design of such vaccines. We then review trials by disease type. Despite great efforts on the part of individual investigative groups, most trials to date have not yielded data from which firm conclusions can be drawn. The reasons for this include nonstandard DC preparation and vaccination protocols, use of different antigen preparations, variable means of immune assessment, and nonrigorous criteria for defining clinical response. While extensive animal studies have been conducted using DCs, optimal parameters in humans remain to be established. Unanswered questions include optimal cell dose, use of mature versus immature DCs for vaccination, optimal antigen preparation, optimal route, and optimal means of assessing immune response. It is critical that these questions be answered, as DC therapy is labor- and resource-intensive. Cooperation is needed on the part of the many investigators in the field to address these issues. If such cooperation is not forthcoming, the critical studies that will be required to make DC therapy a clinically and commercially viable enterprise will not take place, and this therapy, so promising in preclinical studies, will not be able to compete with the many other new approaches to cancer therapy presently in development. Trials published in print through June 2003 are included. We exclude single case reports, except where relevant, and trials with so many variables as to prevent interpretation about DC therapy effects.     

Changes in public order after the opening of a medically supervised safer injecting facility for illicit injection drug users

Background

North America''s first medically supervised safer injecting facility for illicit injection drug users was opened in Vancouver on Sept. 22, 2003. Although similar facilities exist in a number of European cities and in Sydney, Australia, no standardized evaluations of their impact have been presented in the scientific literature.

Methods

Using a standardized prospective data collection protocol, we measured injection-related public order problems during the 6 weeks before and the 12 weeks after the opening of the safer injecting facility in Vancouver. We measured changes in the number of drug users injecting in public, publicly discarded syringes and injection-related litter. We used Poisson log-linear regression models to evaluate changes in these public order indicators while considering potential confounding variables such as police presence and rainfall.

Results

In stratified linear regression models, the 12-week period after the facility''s opening was independently associated with reductions in the number of drug users injecting in public (p < 0.001), publicly discarded syringes (p < 0.001) and injection-related litter (p < 0.001). The predicted mean daily number of drug users injecting in public was 4.3 (95% confidence interval [CI] 3.5–5.4) during the period before the facility''s opening and 2.4 (95% CI 1.9–3.0) after the opening; the corresponding predicted mean daily numbers of publicly discarded syringes were 11.5 (95% CI 10.0–13.2) and 5.4 (95% CI 4.7–6.2). Externally compiled statistics from the city of Vancouver on the number of syringes discarded in outdoor safe disposal boxes were consistent with our findings.

Interpretation

The opening of the safer injecting facility was independently associated with improvements in several measures of public order, including reduced public injection drug use and public syringe disposal.Many cities are experiencing epidemics of bloodborne diseases as a result of illicit injection drug use,^1,2,3 and drug overdoses have become a leading cause of death in many urban areas.^4,5,6 Public drug use also plagues many inner city neighbourhoods, and the unsafe disposal of syringes in these settings is a major community concern.^{7,8,9,10,11,12,13}In over 2 dozen European cities and, more recently, in Sydney, Australia, medically supervised safer injecting facilities, where injection drug users (IDUs) can inject previously obtained illicit drugs under the supervision of medical staff, have been established in an effort to reduce the community and public health impacts of illicit drug use.¹⁴ Inside these facilities IDUs are typically provided with sterile injecting equipment, emergency care in the event of overdose, as well as primary care services and referral to addiction treatment.^13,15 Although anecdotal reports have suggested that such sites may improve public order,¹² reduce the number of deaths from overdose¹⁶ and improve access to care,¹⁷ no standardized evaluations of their impact are available in the scientific literature.¹⁸On Sept. 22, 2003, health officials in Vancouver opened a government-sanctioned safer injecting facility as pilot project. The facility, the first in North America, is centrally located in Vancouver''s Downtown Eastside, which is the most impoverished urban neighbourhood in Canada and home to well-documented overdose and HIV epidemics among the estimated 5000 IDUs who reside there.^19,20 Federal approval for the 3-year project was granted on the condition that the health and social impacts of the facility be rigorously evaluated. Although evaluation of the facility''s impact on certain outcomes (e.g., HIV incidence) is ongoing and will take several years, it is now possible to examine the impacts of the site on public order. Therefore, we conducted this study to test the hypothesis that changes in improperly discarded syringes and public drug use would be observed after the opening of the safer injecting facility.     

Dipolar assisted rotational resonance NMR of tryptophan and tyrosine in rhodopsin

Two dimensional (2D) solid-state (13)C.(13)C dipolar recoupling experiments are performed on a series of model compounds and on the visual pigment rhodopsin to establish the most effective method for long range distance measurements in reconstituted membrane proteins. The effects of uniform labeling, inhomogeneous B(1) fields, relaxation and dipolar truncation on cross peak intensity are investigated through NMR measurements of simple amino acid and peptide model compounds. We first show that dipolar assisted rotational resonance (DARR) is more effective than RFDR in recoupling long-range dipolar interactions in these model systems. We then use DARR to establish (13)C-(13)C correlations in rhodopsin. In rhodopsin containing 4'-(13)C-Tyr and 8,19-(13)C retinal, we observe two distinct tyrosine-to-retinal correlations in the DARR spectrum. The most intense cross peak arises from a correlation between Tyr268 and the retinal 19-(13)CH(3), which are 4.8 A apart in the rhodopsin crystal structure. A second cross peak arises from a correlation between Tyr191 and the retinal 19-(13)CH(3), which are 5.5 A apart in the crystal structure. These data demonstrate that long range (13)C em leader (13)C correlations can be obtained in non-crystalline integral membrane proteins reconstituted into lipid membranes containing less than 150 nmoles of protein. In rhodopsin containing 2-(13)C Gly121 and U-(13)C Trp265, we do not observe a Trp-Gly cross peak in the DARR spectrum despite their close proximity (3.6 A) in the crystal structure. Based on model compounds, the absence of a (13)C em leader (13)C cross peak is due to loss of intensity in the diagonal Trp resonances rather than to dipolar truncation.     

In search of improved fat transfer viability: a quantitative analysis of the role of centrifugation and harvest site

Fat grafting is an unpredictable procedure that continues to challenge the field of plastic surgery due to irregular resorption. Applications for this procedure are broad in both reconstructive and cosmetic plastic surgery. Fat grafts are carefully obtained and manipulated to obtain better graft takes and results, yet there is no universal agreement on what constitutes an ideal methodology. The present study examines adipocyte viability from four commonly used donor sites in five subjects. No statistical differences in adipocyte viability were demonstrated among abdominal fat, thigh fat, flank fat, or knee fat donor sites that were immediately removed and untreated (p < 0.225). In addition, no differences were observed in representative tissue samples that were removed and centrifuged (thigh, p = 0.508; knee, p = 0.302; flank, p = 0.088; abdomen, p = 0.533). On the basis of these quantitative data, neither harvest location nor centrifugation demonstrated any advantage in terms of lipocyte viability. Fat tissue transfers from these common sites may be considered equal, and centrifugation does not appear to enhance immediate fat tissue viability before implantation.