The coming of age of agroforestry

The success of modern agricultural and forestry production can be largely attributed to monoculture systems using a few select species. In the drive for maximizing yield and profit, the age‐old tradition of using combined farming systems was essentially avoided and in some cases this has resulted in environmental problems such as land and water degradation and increased land clearing. During the last 30 years, however, the positive benefits of agroforestry to the producer and the environment have been increasingly recognized. Combining trees and crops in spatial or temporal arrangements has been shown to improve food and nutritional security and mitigate environmental degradation, offering a sustainable alternative to monoculture production. By providing supportive and complimentary roles with a flexible approach, agroforestry can offer specific social and environmental benefits across a range of landscapes and economies. More research and effort is needed to explore the full potential of agroforestry applications and to fuel awareness. As the plethora of benefits of agroforestry are realized, modern land‐use systems are evolving towards a more sustainable and holistic approach to land management. Copyright © 2007 Society of Chemical Industry     

Characterization of Thermal-Sprayed HAP and HAP/TiO<Subscript>2</Subscript> Coatings for Biomedical Applications

In the present study, hydroxyapatite (HAP) coating along with HAP/TiO₂ coating has been deposited by high-velocity flame spray (HVFS) technique onto 316LSS. Titania was used as a bond coat and HAP as top coat in HAP/TiO₂ coating. The main aim of the study is to investigate the corrosion behavior of thermal spray coating of HAP and HAP/TiO₂ on steel. Electrochemical corrosion testing was carried out using potentiodynamic polarization test. The corrosion behavior of bare and as-sprayed specimens was analyzed in simulated body fluid known as Hank’s solution. As-sprayed specimens along with corroded specimens were further characterized by XRD, SEM/EDS, and x-ray mapping analysis. It was observed that the HAP/TiO₂ coating possessed higher microhardness (280 Hv) as compared to HAP coating (254 Hv). Surface roughness also got enhanced in case of HAP/TiO₂ coating (9.35 μm) as compared to pure HAP coating (7.37 μm). The porosity of the HAP coating was found to be higher than the bond coating. It was observed that the Ca/P ratio almost resembled that of the natural bone composition. The corrosion resistance of steel increased after the deposition of HAP and HAP/TiO₂ coatings. The maximum corrosion resistance was exhibited by HAP/TiO₂ coating.     

Discovery and Mechanism of Type III Secretion System Inhibitors

The Type III Secretion System (TTSS) is indispensable for virulence of many Gram-negative pathogenic bacteria, including Escherichia coli, Salmonella spp., Yersinia spp., Vibrio spp., Chlamydia spp., Shigella spp., Pseudomonas spp., Xanthomonas spp., and Auromonas spp. Such pathogenic bacteria are responsible for diseases such as plague, shigellosis, chlamydia, cholera, pneumonia, and gastroenteritis. This review offers insights into the known inhibitors of the TTSS, their discovery, and their mode of action.     

Superantigen activation of immune cells evokes epithelial (T84) transport and barrier abnormalities via IFN-gamma and TNF alpha: inhibition of increased permeability, but not diminished secretory responses by TGF-beta2

Superantigens (SAgs) are extremely potent stimulants of T cell activity that have been implicated in the etiopathophysiology of inflammatory disease. Here, we tested the hypothesis that Staphylococcus aureus enterotoxin B (SEB), a model SAg, can alter epithelial transport and/or barrier functions via immune stimulation. Confluent monolayers of the human colonic T84 epithelial cell line, grown on filter supports, were cocultured with SEB +/- PBMC. Subsequently, T84 transport (consisting of baseline short-circuit current (Isc, indicates net ion transport) and secretory responses to carbachol and forskolin) and barrier functions (consisting of transepithelial resistance and fluxes of 3H-labeled mannitol and 51Cr-EDTA) were examined in Ussing chambers. T84 monolayers cocultured with SEB-activated PBMC displayed a time- and dose-dependent decrease in secretory responses to carbachol and forskolin and a significant increase in permeability. These dramatic changes in epithelial function were not due to reduced epithelial viability. Neutralizing Abs to IFN-gamma partially prevented the transport abnormalities, and Abs to TNF-alpha inhibited the increase in epithelial permeability. Abs to IL-1beta and IL-6 did not modulate the SEB-activated PBMC-induced T84 pathophysiology. Addition of TGF-beta2 to conditioned medium from SEB-activated PBMC partially inhibited the increase in T84 permeability but did not affect the transport abnormalities. We conclude that SAgs can elicit epithelial irregularities characteristic of enteric inflammation and that IFN-gamma and TNF-alpha are key mediators in this coculture model of epithelial dysfunction. Additionally, we would highlight the role that TGF-beta2 may play in preventing prolonged increases in epithelial permeability.     

Evaluation of natural Psoroptes ovis (Acarina: Psoroptidae) soluble proteins as candidate vaccine immunogens

In this study potential vaccine candidate immunogens were identified and evaluated in a vaccine challenge trial. Calves vaccinated with a partially purified fraction of Psoroptes ovis-soluble proteins had 8 of 14 calves free of palpable lesions 8 wk after a challenge infestation. A self-grooming behavioral response elicited by a pruritic immediate-type allergic reaction was believed to be an effector in protecting the vaccinated calves from a clinical P. ovis infestation.