2-Pyrrolidinone and succinimide endogenously present in several mammalian species

2-Pyrrolidinone and succinimide were identified in blood plasma of man, rat, and mouse. Dog plasma contained only traces of 2-pyrrolidinone not exceeding significantly the detection limit of our GCMS-method. Succinimide but not 2-pyrrolidinone could also be found in the brains of rat and mouse. Evidence is presented for a metabolic pathway leading from 2-pyrrolidinone to succinimide, with 5-hydroxy-2-pyrrolidinone as an intermediate.     

A comparison of the antifouling/foul-release characteristics of non-biocidal xerogel and commercial coatings toward micro- and macrofouling organisms

Five non-biocidal xerogel coatings were compared to two commercial non-biocidal coatings and a silicone standard with respect to antifouling (AF)/fouling-release (FR) characteristics. The formation and release of biofilm of the marine bacterium Cellulophaga lytica, the attachment and release of the microalga Navicula incerta, and the fraction removal and critical removal stress of reattached adult barnacles of Amphibalanus amphitrite were evaluated in laboratory assays. Correlations of AF/FR performance with surface characteristics such as wettability, surface energy, elastic modulus, and surface roughness were examined. Several of the xerogel coating compositions performed well against both microfouling organisms while the commercial coatings performed less well toward the removal of microalgae. Reattached barnacle adhesion as measured by critical removal stress was significantly lower on the commercial coatings when compared to the xerogel coatings. However, two xerogel compositions showed release of 89-100% of reattached barnacles. These two formulations were also tested in the field and showed similar results.     

Novel photoreception system in sponges? Unique transmission properties of the stalk spicules from the hexactinellid Hyalonemasieboldi

Sponges (phylum Porifera) of the classes Hexactinellida and Demospongiae possess a skeleton composed of siliceous spicules, which are synthesized enzymatically. The longest spicules are found among the Hexactinellida, with the stalk spicules (length: 30 cm; diameter: 300 microm) of Hyalonema sieboldi as prominent examples. These spicules are constructed around a central axial filament, which is formed by approximately 40 siliceous layers. The stratified spicules function as optical glass fibers with unique properties. If free-spaced coupled with a white light source (WLS), the entire fiber is illuminated. Special features of the light transmission: (i) only wavelengths between 615 and 1310 nm can pass through the fibers and (ii) light below wavelengths of 615 nm and above 1310 nm is completely cut-off. The transmission efficiency is around 60% (measured at 1080-1100 nm [length of the fiber: 5 cm]). The spicules acts as sharp high- and low-pass filters, suggesting that these silica-based fibers might be involved in a photoreception system. This assumption is supported by the finding that sponges are provided with a bioluminescent system. It is hypothesized that the spicules/siliceous fibers might be involved in a photoreception system in these animals.     

Antifouling character of 'active' hybrid xerogel coatings with sequestered catalysts for the activation of hydrogen peroxide

Halide-permeable xerogel films prepared from sols containing 50 mol% aminopropyltriethoxysilane (APTES)/50 mol% tetraethoxysilane (TEOS) or 10 mol% APTES/90 mol% TEOS and 0.015 M selenoxide or telluride catalyst in the sol gave reduced settlement of cypris larvae of the barnacle Balanus amphitrite and larvae of the tubeworm Hydroides elegans in the presence of artificial seawater (ASW) and hydrogen peroxide (5-100 microM) relative to glass controls. Settlement of Ulva zoospores was lower on both the 50 mol% APTES/50 mol% TEOS and 10 mol% APTES/90 mol% TEOS xerogel formulations in comparison with glass controls with or without the added catalyst. The 50 mol% APTES/50 mol%TEOS xerogel containing telluride catalyst gave reduced settlement of Ulva zoospores in the presence of 100 microM H(2)O(2) in ASW compared with the same coating without added peroxide. Scanning electron microscopy and XPS data suggest that exposure to H(2)O(2) does not lead to chemical or morphological changes on the xerogel surface.     

Feasibility and Effectiveness of Basic Lymphedema Management in Leogane,Haiti, an Area Endemic for Bancroftian Filariasis

Background

Approximately 14 million persons living in areas endemic for lymphatic filariasis have lymphedema of the leg. Clinical studies indicate that repeated episodes of bacterial acute dermatolymphangioadenitis (ADLA) lead to progression of lymphedema and that basic lymphedema management, which emphasizes hygiene, skin care, exercise, and leg elevation, can reduce ADLA frequency. However, few studies have prospectively evaluated the effectiveness of basic lymphedema management or assessed the role of compressive bandaging for lymphedema in resource-poor settings.

Methodology/Principal Findings

Between 1995 and 1998, we prospectively monitored ADLA incidence and leg volume in 175 persons with lymphedema of the leg who enrolled in a lymphedema clinic in Leogane, Haiti, an area endemic for Wuchereria bancrofti. During the first phase of the study, when a major focus of the program was to reduce leg volume using compression bandages, ADLA incidence was 1.56 episodes per person-year. After March 1997, when hygiene and skin care were systematically emphasized and bandaging discouraged, ADLA incidence decreased to 0.48 episodes per person-year (P<0.0001). ADLA incidence was significantly associated with leg volume, stage of lymphedema, illiteracy, and use of compression bandages. Leg volume decreased in 78% of patients; over the entire study period, this reduction was statistically significant only for legs with stage 2 lymphedema (P = 0.01).

Conclusions/Significance

Basic lymphedema management, which emphasized hygiene and self-care, was associated with a 69% reduction in ADLA incidence. Use of compression bandages in this setting was associated with an increased risk of ADLA. Basic lymphedema management is feasible and effective in resource-limited areas that are endemic for lymphatic filariasis.