Ultrastructure changes induced by dry film formation of a trisodium phosphate blend, antimicrobial solution

Trisodium phosphate (TSP) has been reported to have antimicrobial activity and is approved by the U.S. Department of Agriculture for use in food processing applications. A novel (U.S. Patent 6,184,198), antimicrobial solution containing a blend of TSP, sodium bicarbonate, and sodium carbonate (TSP blend) has demonstrated effective inhibition of microbial contamination in a broad spectrum of applications. This high-resolution cold field emission scanning electron microcopy (LVSEM) investigation details structural changes and dry film formation in various classes of microbes as a mechanism for antimicrobial activity of this solution. The results showed that this TSP blend solution completely inhibited the growth of pathogenic E. coli O157:H7, and Salmonella bacteria, the mold Cryptococcus, as well as a Norwalk virus surrogate-feline calicivirus. Results by LVSEM confirmed that the antimicrobial effect was induced when encapsulating the target microbes in a high lubricity film that is formed around these organisms as the solution dries. The thickness of the film was estimated to be approximately 60 nm.     

Advantages of visualization of organelle structure by high resolution scanning electron microscopy

Examination of subcellular structures in detail and in three dimensions (3D) by scanning electron microscopy (SEM) is now possible on a routine basis due to improvements in design of the modern scanning electron microscope and new methods of specimen preparation involving chemical removal of the cytosol and the cytoskeleton. Cells which have been fixed, frozen, cleaved, thawed, and subjected to cytosol removal exhibit constituents such as nuclear chromatin, cisternae of endoplasmic reticulum, mitochondria, and the Golgi complex in bold relief. This permits examination by SEM in 3D of these structures from several aspects at a resolution close to that of conventional transmission electron microscopy (TEM). As a result, minute changes in the 3D structure of subcellular components can now be easily and conveniently examined from many specimens and anatomical sites, in development, in a variety of physiological processes, and in disease. The SEM method offers many advantages over the various TEM techniques now used for similar purposes, since much larger areas of the specimen can be surveyed by SEM in a given time, sectioning is not required and minute 3D changes in nuclear and organelle structure can be identified and analyzed more easily. The advantages are such that a host of biological questions can now be answered by SEM which, so far, have resisted solution using only TEM techniques. In addition, a new field of pathological diagnosis using SEM may develop, using the advantages offered by the technique in exploring the cell's interior as well as cellular tissue organization.     

Chemical extraction of the cytosol using osmium tetroxide for high resolution scanning electron microscopy.

Detailed examination of subcellular structures in three dimensions (3D) by high resolution scanning electron microscopy (HRSEM) is now possible due to improvements in the design of the scanning electron microscope and the introduction of methods of specimen preparation using chemical removal of the cytosol and cytoskeleton by dilute osmium tetroxide. Cells which have been fixed, frozen, cleaved, thawed, and subjected to cytosol extraction display intact intracellular structures in 3D including nuclear chromatin, endoplasmic reticulum, mitochondria, and the Golgi complex at a resolution close to that of conventional biological transmission electron microscopy (TEM). Small changes in the 3D structure of subcellular components can be conveniently examined in this way in development, in a variety of physiological processes and in disease. Broad areas of the specimen can be quickly surveyed by HRSEM since sectioning is not required and specimens of comparatively large size (up to 5 mm3) can be placed in the microscope. Extraction of the cytosol with dilute osmium tetroxide (OsO4) exposes subcellular structures in relief, permitting their examination in 3D from several aspects. However, the OsO4 extraction technique is limited, since significant intracellular structures, such as the cytoskeleton, vesicles, and antibody binding sites can be removed or inactivated during the cytosol removal steps.     

Impaired Retromer Function in Niemann-Pick Type C Disease Is Dependent on Intracellular Cholesterol Accumulation

Niemann-Pick type C disease (NPC) is a rare inherited neurodegenerative disorder characterized by an accumulation of intracellular cholesterol within late endosomes and lysosomes due to NPC1 or NPC2 dysfunction. In this work, we tested the hypothesis that retromer impairment may be involved in the pathogenesis of NPC and may contribute to increased amyloidogenic processing of APP and enhanced BACE1-mediated proteolysis observed in NPC disease. Using NPC1-null cells, primary mouse NPC1-deficient neurons and NPC1-deficient mice (BALB/cNctr-Npc1m1N), we show that retromer function is impaired in NPC. This is manifested by altered transport of the retromer core components Vps26, Vps35 and/or retromer receptor sorLA and by retromer accumulation in neuronal processes, such as within axonal swellings. Changes in retromer distribution in NPC1 mouse brains were observed already at the presymptomatic stage (at 4-weeks of age), indicating that the retromer defect occurs early in the course of NPC disease and may contribute to downstream pathological processes. Furthermore, we show that cholesterol depletion in NPC1-null cells and in NPC1 mouse brains reverts retromer dysfunction, suggesting that retromer impairment in NPC is mechanistically dependent on cholesterol accumulation. Thus, we characterized retromer dysfunction in NPC and propose that the rescue of retromer impairment may represent a novel therapeutic approach against NPC.     

Evaluation of European energy behavioural change programmes

This article is based on the findings of the BEHAVE Project (Evaluation of Energy Behavioural Change Programmes) which was supported by the European Commission under the EU Intelligent Energy–Europe (IEE) Programme. The project started with a review of behavioural theories and their applicability in the development and evaluation of energy-related behavioural change programmes, progressed to a case study analysis and finished with a publication of guidelines for programme developers and policy makers. This paper concentrates on the results of the case study analysis and the recommendations arising from it. In the case study analysis, information was collected on almost 100 cases aiming at behavioural change in energy use from 11 European countries. More detailed information was collected on 41 cases which were subject to meta-analysis to identify success factors and weak points and to gather information on the current evaluation practices in such programmes. The meta-analysis was carried out in five phases: context (pre-planning), planning, implementation, monitoring and evaluation. Planning and evaluation were recognised as two of the most critical phases. Many of the programmes operated with quite formal plans but were typically not based on scientific theories or evidence. In many cases, there was lack of market segmentation; the goals were not targeted and the programmes tried to offer “everything to everybody”. A multitude of ex-post evaluation methods for programme impacts were reported ranging from participant surveys, testing and comparison with control groups to top–down method evaluating the impact of several programmes focusing on the same target group. Process evaluation (25 cases) was slightly less common than impact evaluation (29 cases). Evaluation of the cost-effectiveness of the programmes was a rarity, most likely due to difficulties in quantitative impact evaluation.     

Norms and screening utility of the Dutch version of the Children's Depression Inventory in clinical and nonclinical youths.

This study aimed to (a) assess relationships between the Children's Depression Inventory (CDI) and DSM-oriented depression and anxiety scales of the Youth Self Report, (b) develop reliable norms for the CDI, and (c) determine CDI cutoff scores for selecting youngsters at risk for depression and anxiety. A total of 3,073 nonclinical and 511 clinically referred children and adolescents from The Netherlands and Belgium were included. Results showed that CDI scores were significantly related to DSM-oriented symptoms of both depression and anxiety. CDI scores correlated highly with depression symptoms and moderately with anxiety symptoms. Norms for the CDI were determined by means of multiple regression analysis and depended on sex, age, and country. CDI cutoff scores for selecting individuals at risk for depression and anxiety as measured by the DSM-oriented depression and anxiety scales of the Youth Self Report were determined by means of multiple regression analysis and receiver operating characteristic analysis. A CDI score of 16 was found to have the most optimal balance between sensitivity and specificity for depression, whereas a score of 21 provided the best sensitivity and specificity for anxiety in a subsample of children. We conclude that the CDI is an effective instrument for screening depression and to a lesser extent anxiety in primary and secondary care centers, before applying further assessment of high-risk individuals. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Surface Modification of Coir Fibers for Extended Hydrophobicity and Antimicrobial Property for Possible Geotextile Application

Experimental investigations are conducted to study the effectiveness of protective coating with cashew nut shell liquid (CNSL) on coir. CNSL solution has been applied on suitably pretreated coir yarns and coating concentrations are optimized to reduce moisture absorption and microbial growth. Two common cellulose and lignin degrading fungi (Aspergillus niger and Rhizopus stolonifer) have been taken as test organisms. Qualitative and quantitative analyses are carried out to measure fungal growth on untreated and treated fibers. The study shows that treated fibers inhibit the development of fugal growth on fiber surface by 95%. The reduced moisture absorption and improved hydrophobicity of the treated yarns are also reported. Increase in tensile strength up to 17% is noticed. The better properties achieved are explained on the basis of selection of the coating methodology and also the interfacial features of the coatings with the coir fiber. The results indicate the possibility of future application of such treated fibers in geotextiles having better performance compared to the untreated counterparts.