Proteomic studies in animal models of diabetes

The aim of this review is to provide an overview of proteomic studies in animal models of diabetes and to give some insight into the different methods available today in the rapidly developing field of proteomics. A summary of 31 papers published between 1997 and 2007 is presented. For instance, proteomics has been used to study the development of both type 1 and type 2 diabetes, diabetic complications in tissues like heart, kidney and retina and changes after treatment with anti-diabetic drugs like peroxisome proliferator-activated receptors agonists. Together, these studies give a good overview of a number of experimental approaches. Proteomics holds the promise of providing major contributions to the field of diabetes research. However, to achieve this, a number of issues need to be resolved. Appropriate data representation to facilitate data comparison, exchange, and verification is required, as well as improved statistical assessment of proteomic experiments. In addition, it is important to follow up the results with functional studies to be able to make biologically relevant conclusions. The potential of proteomics to dissect complex human disorders is now beginning to be realized. In the future, this will result in new important information concerning diabetes.     

Musculoskeletal disorders among female and male air traffic controllers performing identical and demanding computer work

Operators with identical, demanding computer work (90 female and 97 male air traffic controllers) were found to have high prevalences of disorders (assessed by questionnaire and physical examination) in neck, shoulders and upper back. In spite of the identical work, the women displayed higher prevalences than the men (e.g. neck diagnoses 21% vs. 4%). Disorders in elbows, wrists and hands were less common, with similar rates in both genders. Generally, the psychosocial work environment (assessed by questionnaire) was found to be good, but with large inter-individual variation. Women experienced lower decision latitude than men, particularly regarding influence and freedom at work, but perceived higher social support. Physically, the work was characterized by relatively low angular velocities of upper arms (measured by inclinometry) and wrists (right: < 1 degrees/s during 19% of time, measuring by goniometry), dynamic muscular activities and high time fractions of rest in the trapezius and forearm extensor muscles (measuring by electromyography). There were only minor differences between the genders.     

Ultrastructural evidence for an innervation of epithelial enterochromaffine cells in the guinea pig duodenum

The innervation of the duodenal enterochromaffine cells (E.C.) of the guinea pig was studied at the electronmicroscopic level. Pretreatment with 5-OH-dopamine was performed to visualize catecholaminergic (CA) nervous elements. Near the basement membrane of all examined E.C. in the crypts, bundles of unmyelinated nerve processes were observed, only partly ensheathed in a Schwann cell cover. At least 4 types of processes could be observed. 1) Boutons containing only small clear vesicles, probably cholinergic fibres; 2) boutons with small clear vesicles, and in addition large (greater than 200 nm) granules with a dense matrix (P-type-fibres); 3) boutons with small electron-dense vesicles, probably CA-fibres; and 4) processes with few vesicles but having the appearance of dendrites. No typical synaptic arrangements were observed, but the minimal distance between the E.C. and the nerve bundles was 150 to 250 nm, thus well within the functional limits of the "autonomic gap". Thus epithelial E.C. may be influenced by several types of nervous elements, including CA-fibres.     

Form-Profiling of Optics Using the Geometry Measuring Machine and the M-48 CMM at NIST

We are developing an instrument, the Geometry Measuring Machine (GEMM), to measure the profile errors of aspheric and free form optical surfaces, with measurement uncertainties near 1 nm. Using GEMM, an optical profile is reconstructed from local curvatures of a surface, which are measured at points on the optic’s surface. We will describe a prototype version of GEMM, its repeatability with time, a measurements registry practice, and the calibration practice needed to make nanometer resolution comparisons with other instruments. Over three months, the repeatability of GEMM is 3 nm rms, and is based on the constancy of the measured profile of an elliptical mirror with a radius of curvature of about 83 m. As a demonstration of GEMM’s capabilities for curvature measurement, profiles of that same mirror were measured with GEMM and the NIST Moore M-48 coordinate measuring machine. Although the methods are far different, two reconstructed profiles differ by 22 nm peak-to-valley, or 6 nm rms. This comparability clearly demonstrates that with appropriate calibration, our prototype of the GEMM can measure complex-shaped optics.     

Control applications of nonlinear convex programming

Since 1984 there has been a concentrated effort to develop efficient interior-point methods for linear programming (LP). In the last few years researchers have begun to appreciate a very important property of these interior-point methods (beyond their efficiency for LP): they extend gracefully to nonlinear convex optimization problems. New interior-point algorithms for problem classes such as semidefinite programming (SDP) or second-order cone programming (SOCP) are now approaching the extreme efficiency of modern linear programming codes. In this paper we discuss three examples of areas of control where our ability to efficiently solve nonlinear convex optimization problems opens up new applications. In the first example we show how SOCP can be used to solve robust open-loop optimal control problems. In the second example, we show how SOCP can be used to simultaneously design the set-point and feedback gains for a controller, and compare this method with the more standard approach. Our final application concerns analysis and synthesis via linear matrix inequalities and SDP.     

Subjective Probability Intervals: How to Reduce Overconfidence by Interval Evaluation.

Format dependence implies that assessment of the same subjective probability distribution produces different conclusions about over- or underconfidence depending on the assessment format. In 2 experiments, the authors demonstrate that the overconfidence bias that occurs when participants produce intervals for an uncertain quantity is almost abolished when they evaluate the probability that the same intervals include the quantity. The authors successfully apply a method for adaptive adjustment of probability intervals as a debiasing tool and discuss a tentative explanation in terms of a naive sampling model. According to this view, people report their experiences accurately, but they are naive in that they treat both sample proportion and sample dispersion as unbiased estimators, yielding small bias in probability evaluation but strong bias in interval production. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Vibration in car repair work

The main objective of the study was to find efficient hand tools which caused only minor vibration loading. Vibration measurements were carried out under standardised working conditions. The time during which car body repairers in seven companies were exposed to vibration was determined. Chisel hammers, impact wrenches, sanders and saws were the types of tools which generated the highest vibration accelerations. The average daily exposure at the different garages ranged from 22 to 70 min. The risk of vibration injury is currently rated as high. The difference between the highest and lowest levels of vibration was considerable in most tool categories. Therefore the choice of tool has a major impact on the magnitude of vibration exposure. The importance of choosing the right tools and working methods is discussed and a counselling service on vibration is proposed.     

Degradation of phytate by Pichia kudriavzevii TY13 and Hanseniaspora guilliermondii TY14 in Tanzanian togwa

The fermented cereal-based gruel togwa is used as weaning food for children in Tanzania. Togwa is rich in minerals but these are often not available for uptake in the human intestine due to natural inhibitors, such as phytate (IP(6)). The yeasts Pichia kudriavzevii TY13, Hanseniaspora guilliermondii TY14 and TY20, isolated from Tanzanian togwa, and selected for high phytase activity in complex yeast medium YPD, were now studied regarding their ability to degrade IP(6) in maize-based model togwa. A modified constitutively high-phytase producing Saccharomyces cerevisiae BY80 and commercial Aspergillus ficuum phytase were included for comparison. In addition, a strain of Lactobacillus plantarum was included in the model-togwa set-up. All yeasts in the study grew and reached final cell density 1.5-2 log units higher than the start value. S. cerevisiae BY80 degraded 85% of the IP(6) in 48 h; the same degradation level as with A. ficuum phytase (89%). Of the togwa-isolated yeasts, P. kudriavzevii TY13 and H. guilliermondii TY14 showed strong phytate degradation in the model-togwa; 95% or more of the initial IP(6) was degraded after 48 h. This corresponds to a remaining level of 0.4 and 0.3μmol IP(6)/g dw. Co-inoculation with L. plantarum did not increase IP(6) degradation. Moreover, fermentation with P. kudriavzevii TY13 yielded a successive increase in inorganic phosphate (P(i)), from 0.7 to 5.4 mM, suggesting a phytase production in TY13 which is fairly insensitive to P(i) repression. The study shows that phytate in a model togwa is available for yeast phytase enzymes, and addresses the importance of strain selection for effectively degrading the phytate. Certain yeasts originating from togwa seem to have developed a natural high phytase production, and P. kudriavzevii TY13 and H. guilliermondii TY14 seem particularly well adapted to phytate degradation in togwa, and is our choice for further studies and strain improvement.     

Processing of tomato: impact on in vitro bioaccessibility of lycopene and textural properties

BACKGROUND: Human studies have demonstrated that processing of tomato can greatly increase lycopene bioavailability. However, the difference between processing methods is not widely investigated. In the current study different thermal treatments of tomato were evaluated with regard to their impact on in vitro bioaccessibility and retention of lycopene and β‐carotene as well as textural properties. Thermal treatments used were low (60 °C) and high (90 °C) temperature blanching followed by boiling. RESULTS: Lycopene was relatively stable during thermal treatment, whereas β‐carotene was significantly (P < 0.05) reduced by all heat treatments except for low temperature blanching. In vitro bioaccessibility of lycopene was significantly increased from 5.1 ± 0.2 to 9.2 ± 1.8 and 9.7 ± 0.6 mg kg^?1 for low and high temperature blanching, respectively. An additional boiling step after blanching did not further improve lycopene bioaccessibility for any treatment, but significantly reduced the consistency of low temperature treated samples. CONCLUSION: Choice and order of processing treatments can have a large impact on both lycopene bioavailability and texture of tomato products. Further investigations are needed, but this study provides one of the first steps towards tomato products tailored to optimise nutritional benefits. Copyright © 2010 Society of Chemical Industry