The Dutch Renal Artery Stenosis Intervention Cooperative (DRASTIC) Study: rationale, design and inclusion data

RATIONALE: Renal artery stenosis may lead to renovascular hypertension, risking multiple organ damage including damage to the contralateral kidney. Progression of stenosis may impair the function of the affected kidney. It is important to identify individuals with this disease among hypertensive patients. The first aim of the Dutch Renal Artery Stenosis Intervention Cooperative (DRASTIC) study is to assess the prevalence of renal artery stenosis in patients with well-defined forms of drug-resistant hypertension, and to determine the predictive value of clinical characteristics and diagnostic tests in these pre-selected patients. With regard to treatment, the effect of renal angioplasty on hypertension is disappointing in atherosclerotic stenosis and technical failure frequently occurs. Therefore, the second aim is to compare the effects of balloon angioplasty and antihypertensive medication on blood pressure in patients with atherosclerotic renal artery stenosis. DESIGN HYPERTENSIVE: patients receiving standard antihypertensive medication in whom diastolic blood pressure remained > or =95 mmHg during three consecutive visits to the outpatient clinic underwent full diagnostic work-up, including renal arteriography. The prevalence of renal artery stenosis in this well-defined patient group was then established, and the predictive value of the various diagnostic tests was assessed. Patients with an atherosclerotic renal artery stenosis of > or =50% were then randomly assigned to balloon angioplasty or to treatment with antihypertensive drugs. After 1 year of intensive follow-up of blood pressure and renal function, re-arteriography was performed. CONCLUSION: In total, 1205 patients have been included in the study, about 500 have received diagnostic work-up, and it is expected that 100 patients will be randomly assigned for renal angioplasty or medical treatment.     

Getting even for customer mistreatment: The role of moral identity in the relationship between customer interpersonal injustice and employee sabotage.

Research on the "dark side" of organizational behavior has determined that employee sabotage is most often a reaction by disgruntled employees to perceived mistreatment. To date, however, most studies on employee retaliation have focused on intra-organizational sources of (in)justice. Results from this field study of customer service representatives (N = 358) showed that interpersonal injustice from customers relates positively to customer-directed sabotage over and above intra-organizational sources of fairness. Moreover, the association between unjust treatment and sabotage was moderated by 2 dimensions of moral identity (symbolization and internalization) in the form of a 3-way interaction. The relationship between injustice and sabotage was more pronounced for employees high (vs. low) in symbolization, but this moderation effect was weaker among employees who were high (vs. low) in internalization. Last, employee sabotage was negatively related to job performance ratings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Monitoring pilot projects using bored tunnelling: the Second Heinenoord Tunnel and the Botlek Rail Tunnel

Two pilot projects for bored tunnelling in soft soil have been undertaken in the Netherlands. The monitoring was commissioned under the authority of the Centre for Underground Construction (COB). The research related to the Second Heinenoord Tunnel and the Botlek Rail Tunnel is described. Boring works for the Second Heinenoord Tunnel have been completed, while the boring of the Botlek Rail Tunnel began in spring of 1999. Experience from the first project will be put into use for the development of the latter. Both monitoring schemes have three logical phases: predictions, measuring and evaluation. An overview of all instrumentation and a selection of the results of the Second Heinenoord tunnel is given.     

Optimisation of calcium-dependent protease and cathepsin D assays in ostrich muscle and the effect of chemical and physical dry-curing parameters

The best conditions for the assay of cathepsin D and Ca²⁺-dependent pro tease (CDP) activity in ostrich muscle was established in order to have a simple, rapid and reliable method for its determination. Measurements of A_280nm of TCA-soluble peptides and amino acid digests of casein and haemoglobin were used for measuring proteolytic activity in muscle extracts. The best conditions for the reliable determination of cathepsin D activity were found to be the incubation of an enzyme extract for 1 hr at 55 °C in a reaction mixture containing 0.9% (w/v) haemoglobin in 50 mM sodium formate buffer, pH 3.7. Characterization of the assay system for CDPs, obtained after phenyl-Sepharose chromatography, indicated that proteolytic degradation of casein by CDPs was linear with time up to 30 min at 30 °C and up to 0.1 units of activity. The effect of NaCl, KCl, nitrate, ascorbic acid, phosphate, glucose and sucrose on ostrich muscle CDP and cathepsin D activities has been studied. Salt (NaCl and KCl) acts as a strong inhibitor of proteolytic activity. Sodium and potassium nitrates (in the range 0–1000 mg l⁻¹) affected activity to varying degrees. CDP activity was enhanced by sodium nitrate concentrations below 700 mg l⁻¹ and unchanged by potassium nitrate. Cathepsin D activity was inhibited to some extent by sodium nitrate above 200 mg l⁻¹ and completely by potassium nitrate. Results showed that phosphate is an inhibitor of both activities. High concentrations of ascorbic acid (above 6 g l⁻¹) inhibited cathepsin D activity. Glucose (up to 2g l⁻¹) activated cathepsin D activity and inhibited CDP activity (up to 1 g l⁻¹). Sucrose activated enzyme activities at very low concentrations (1 × 10⁻³ M) and inhibited activities above 1 × 10⁻³ M.     

Factors affecting the immobilization of metals in geopolymerized flyash

Geopolymerization, a fairly new technology based on a very old principle, has emerged during the last few years as a possible solution to some waste stabilization and solidification problems. Some commercial successes have been achieved, although the technique remains fairly unknown as well as seemingly unpopular. It has been shown that most waste materials containing sources of silica and alumina should be capable of taking part in a geopolymerization reaction. In this article, flyash was used as a reactant in creating a geopolymeric matrix for the immobilization of process water containing 25,000 ppm of Cu or Pb cations. By means of X-ray diffraction, scanning electron microscopy (SEM), infrared spectroscopy, Brunauer-Emmett-Teller (BET), compressive strength, as well as kinetic leaching analyses, the main factors influencing matrix stability, immobilization efficiency, and therefore leaching behavior were investigated and discussed qualitatively. It was found that relatively high strengths could be obtained using low Ca flyash. The environment and coordination number of source aluminum and silica seemed to play a major role in the eventual matrix stability. Other factors influencing matrix stability include the alkali metal cation used as well as the type of metal being immobilized. The kinetics of leaching of immobilized metals from the geopolymerized flyash were qualitatively found to proceed along a combination of pore diffusion and boundary diffusion control mechanisms. It is finally concluded that immobilization of metals in geopolymerized flyash proceeds by a combination of physical encapsulation and chemical bonding, with adsorption also thought to play a role.     

The potential contribution of bread buns fortified with beta-carotene-rich sweet potato in Central Mozambique

BACKGROUND: Orange-fleshed sweet potato is an efficacious source of vitamin A. Substituting wheat flour with orange-fleshed sweet potato in processed products could reduce foreign exchange outlays, create new markets for producers, and result in increased vitamin A consumption among consumers provided there is adequate retention of beta-carotene during processing. OBJECTIVE: To explore whether substituting 38% of wheat flour (by weight) in bread buns ("golden bread") with boiled and mashed orange-fleshed sweet potato from fresh roots or rehydrated chips would produce economically viable beta-carotene-rich products acceptable to Mozambican rural consumers. METHODS: Modified local recipes maximized sweet potato content within the limits of consumer acceptability. Sensitivity analysis determined parameters underlying economic viability. Two samples each of buns from five varieties of orange-fleshed sweet potato were analyzed for beta-carotene content. Processed products with at least 15 microg/g product of trans-beta-carotene were considered good sources of vitamin A. RESULTS: Golden bread made from fresh roots of medium-intensity orange-fleshed sweet potato varieties met the good source criterion, but bread from lighter-intensity sweet potato varieties did not. Bread from rehydrated dried chips was not economically viable. Consumers strongly preferred golden bread over pure wheat flour bread because of its heavier texture and attractive appearance. The ratio of the price of wheat flour to that of raw sweet potato root varied from 3.1 to 3.5 among the bakers, whose increase in profit margins ranged from 54% to 92%. CONCLUSIONS: Golden bread is a good source of beta-carotene and is economically viable when the price ratio of wheat flour to raw orange-fleshed sweet potato root is at least 1.5. Widespread adoption during sweet potato harvesting periods is feasible; year-round availability requires storage.     

Afrikander cattle congenital goiter: characteristics of its morphology and iodoprotein pattern

The morphology and some properties of the complex iodoprotein pattern of the genetically determined congenital goiter in Afrikander cattle is described. The goiter contained irregularly shaped follicles which were devoid of colloid and the follicular epithelial cells were elongated, measuring about 20 micrometer in length compared to 10 micrometer for normal thyroid cells. The goiter cells contained apical clusters of larger and more numerous lysosomes than normal thyroid cells. Apical vesicles containing electron-dense material which were in contact with the plasma membrane could be seen in most normal thyroid cells, but were extremely scarce in the goiter. In 36 cell profiles studied none was found. The endoplasmic reticulum cisternae of the goiter differed significantly from normal thyroid cells. Fewer ribosomes were seen to be attached to the membranes of goiter cells. Furthermore, unlike normal thyroid cells, many free polysomes were seen in goiter cells. The characteristics of the unusual iodoprotein pattern of the goiter extract, resolved by gel chromatography and sucrose density gradient centrifugation, were qualitatively and quantitatively similar to that described previously (Endocrinology 91, 470, 1972). A relatively small amount of the total soluble protein was iodinated. Of these, only a 12S sedimenting species was precipitated by antithyroglobulin immunoglobulin. When separated on polyacrylamide gels containing sodium dodecyl sulfate and mercaptoethanol, this 12S species was resolved into at least 14 polypeptide components ranging in molecular weights from less than 66,000--330,000. Three of the bands, representing a small percentage of the total protein, seemed to comigrate with the major polypeptides of thyroglobulin and were also precipitated with rabbit antihyroglobulin immunoglobulin. The data indicate that glycosylation of iodoproteins was not affected although 19S thyroglobulin synthesis and subsequent storage were drastically impaired.     

Models,algorithms and performance analysis for adaptive operating room scheduling

The complex optimisation problems arising in the scheduling of operating rooms have received considerable attention in recent scientific literature because of their impact on costs, revenues and patient health. For an important part, the complexity stems from the stochastic nature of the problem. In practice, this stochastic nature often leads to schedule adaptations on the day of schedule execution. While operating room performance is thus importantly affected by such adaptations, decision-making on adaptations is hardly addressed in scientific literature. Building on previous literature on adaptive scheduling, we develop adaptive operating room scheduling models and problems, and analyse the performance of corresponding adaptive scheduling policies. As previously proposed (fully) adaptive scheduling models and policies are infeasible in operating room scheduling practice, we extend adaptive scheduling theory by introducing the novel concept of committing. Moreover, the core of the proposed adaptive policies with committing is formed by a new, exact, pseudo-polynomial algorithm to solve a general class of stochastic knapsack problems. Using these theoretical advances, we present performance analysis on practical problems, using data from existing literature as well as real-life data from the largest academic medical centre in The Netherlands. The analysis shows that the practically feasible, basic, 1-level policy already brings substantial and statistically significant improvement over static policies. Moreover, as a rule of thumb, scheduling surgeries with large mean duration or standard deviation early appears good practice.     

The production of provitamin A‐rich vegetables in home‐gardens as a means of addressing vitamin A deficiency in rural African communities

Vitamin A deficiency remains a public health problem in the developing world. The highest prevalence of vitamin A deficiency is in Africa and Asia (>30%). Dietary modification, a long‐term strategy to address vitamin A deficiency, complements food fortification and vitamin A supplementation programmes. Provitamin A carotenoids from foods of plant origin are more affordable than preformed vitamin A from animal foods, and many resource‐poor households rely on yellow/orange‐fleshed vegetables and fruits and dark‐green leafy vegetables as their main source of vitamin A. The provitamin A carotenoid content in plant foods varies widely and differences among cultivars of the same food exist. Several factors influence the bioavailability of provitamin A carotenoids. The potential contribution of plant foods to vitamin A status depends on the retention of provitamin A carotenoids after storage, preparation and processing. Home‐gardens can provide households with direct access to provitamin A‐rich vegetables that are not readily available or within their financial reach. The components and critical issues of home‐garden projects are described. Copyright © 2006 Society of Chemical Industry     

Characterisation and determination of the geographical origin of wines. Part I: overview

One of the most challenging analytical issues in terms of wine authenticity is the control of geographical origin. This question becomes more and more important in the current context of a global wine market. Single parameters are often not sufficient on their own to determine the product identity with respect to the wine labelling. Recent developments have shown that control is improved by application of multivariate statistical methods to a combination of composition and isotopic data. In the past years, the official European wine control bodies have been confronted with wines that have had to be judged as suspicious in terms of their sophisticated authenticity, falsifications which are not readily identifiable, especially as it regards the grape variety, and particularly highlighted here the geographical origin. To improve the measures of authenticity control, a project with the title “Establishing of a WINE Data Bank for analytical parameters for wines from Third countries (WINE-DB project, G6RD-CT-2001-00646-WINE-DB)” was initiated in 2002, funded by the European Commission within the fifth framework “Competitive and Sustainable Growth”. The project consortium of this multinational project was composed of official and private laboratories from the European Union, from new European member states and a group of university partners for the statistical evaluation. Within the framework of the WINE-DB project, commercial and authentic wines originating from new European member states (Czech Republic, Hungary and Romania) and from overseas countries (South Africa and Australia) are collected and analysed. More than 1,800 wines from three vintages were analysed. First, a sampling plan for each wine-producing country was developed for the authentic samples taking into account, the surface and the grape variety of wine in the respective country. This sampling plan was used for the commercial samples accordingly. A series of three publications was prepared covering the statistical approaches and the results obtained for authentication of wine. The actual one—Part I—provides an overview on the structure of the project, the developing of the sampling plan, the strategy of sample collection and the analytical scheme.