Plasma-derived proteins in airway defence, disease and repair of epithelial injury

One significant characteristic of the airway mucosa in vivo, that cannot easily be mimicked in vitro, is its microcirculation, which generates a highly dynamic, biologically active milieu of plasma-derived molecules that may pass to the airway lumen in vivo. New data on the mechanisms of airway mucosal exudation indicate that the protein systems of circulating plasma may contribute significantly to the biology and immunology of the lamina propria, its surface epithelium and the luminal surface, not only in injured airways, but also in airways that are activated but display no sign of oedema, epithelial disruption, or increased absorption capacity. We suggest that present knowledge of the mechanisms of plasma exudation, together with rapidly emerging information (not detailed herein) on receptors, target cells and cellular responses to the plasma-derived molecules, must be considered in any realistic model that investigates "immuno-inflammatory" mechanisms of the airway mucosa.     

Early Post Mortem pH decrease in porcine M. longissimus dorsi of PSE, Normal and DFD quality

The purpose of this investigation was to compare the muscle pH at exsanguination and the rate of pH changes in porcine M. longissimus dorsi (LD) of normal, DFD (Dark, Firm, Dry) and PSE (Pale, Soft, Exudative) quality. The pH was continuously measured in the LD in 116 carcasses during the first 50 min post mortem. Calculations were made both on measured pH-values and on pH-values transformed to hydrogen ion concentrations. A regression of pH or hydrogen ion concentration on time was made for each animal. These individual regressions were then combined, using a multivariate analysis to estimate regression curves for each meat quality class. The two methods for expressing pH gave somewhat different results. The relationship between the hydrogen ion concentration and time was found to be linear for normal and DFD muscles and quadratic for PSE muscles. As a consequence of the mathematical properties of pH, the relationship between pH and time was found to be quadratic for the normal and DFD qualities, and linear for the PSE quality. For both methods of calculations the slopes for the regression curves were significantly different between PSE and the other two quality classes with both calculating methods, while the slopes did not differ between normal and DFD muscle qualities. The intercepts of the regression curves differed significantly between PSE and the other two quality classes only when the calculations were made on measured pH-values without transformation. A temporary increase in pH was seen in some normal and PSE carcasses during the measured time period. Development of muscles with PSE characteristics thus seems to be initiated by a combination of a lower muscle-pH already at exsanguination and a faster pH decrease. It is also of importance to consider the special mathematical properties of the pH-value.     

Cytolysis and piecemeal degranulation as distinct modes of activation of airway mucosal eosinophils

In contrast to the protective effect of chronic caloric restriction on tumor development, we have shown that fasting sustained tumor initiation in rat liver by a noninitiating dose of diethylnitrosamine. Here we investigated whether fasting had a similar favorable effect on initiation in the colorectal mucosa in 80 male F344 rats. Animals fasted for 4 days were given a single s.c. dose of azoxymethane (AOM) (20 mg/kg) on the first day of re-feeding, and rates of kinetic proliferative parameters, and development of the pre-neoplastic lesions such as aberrant crypt foci (ACF), were evaluated. Starvation before AOM treatment enhanced the growth of ACF, as shown by the significantly higher crypt multiplicity of fasted/re-fed rats as compared with fully fed rats (3.97 +/- 0.50 vs. 2.64 +/- 0.20, p < or = 0.025). This difference was associated with perturbations in cell death and cell proliferation. Fasting induced apoptosis and depressed cell division, while re-feeding had opposite effects, resulting in a higher percentage of S-phase cells at the time of AOM injection and 2 days thereafter. Starvation-induced apoptosis may represent the mitogenic stimulus to an increase in the number of cells susceptible to AOM damage, and may favor its fixation, leading to enhanced growth of ACF. Our data therefore suggest that fasting/re-feeding enhances colon cancer.     

Fixation of distal femoral osteotomies with self-reinforced poly(L/DL)lactide 70 : 30/bioactive glass composite rods. An experimental study on rats

Self-reinforced poly(L/DL)lactide 70:30/bioactive glass [SR-P(L/DL)LA/bioactive glass] composite rods, 2 mm in diameter and 36 mm in length, were implanted into the dorsal subcutaneous tissue of 16 rats. Osteotomies of the distal femur were fixed with these rods (2 x 15 mm) in 64 other rats. The follow-up times varied from one week to one year. After sacrifice, three-point bending and shear tests, and molecular weight measurements were performed for subcutaneously placed rods. Radiological, histological, histomorphometrical, microradiographic, and oxytetracycline-fluorescence studies of the osteotomized and intact control femora were performed. At 24 weeks the mechanical properties had decreased significantly. Thirty-nine osteotomies healed uneventfully. One of the 64 evaluated osteotomies showed signs of infection at six weeks, and there were 19 non-unions and six delayed unions. In 20 operations the fixation was loose and out of these 14 non-unions were observed. No gross signs of inflammatory or foreign-body reactions were observed. The present investigation showed that the mechanical strength and fixation properties of SR-P(L/DL)LA/bioactive glass composite rods are suitable for fixation of cancellous bone osteotomies in rats as long as the operative technique is correct. The present article is the first report on the application of SR-P(L/DL)LA/bioactive glass composite rods for fixation of cancellous bone osteotomies.     

Industrial ecology in university curriculum: new M.Sc. Programme in Environmental Management and Cleaner Production

To ensure long-term capacity building in the area of industrial ecology, a new M.Sc. Programme in Environmental Management and Cleaner Production has been developed in the framework of the BALTECH consortium, which consists of technical universities in the Baltic Sea region. The programme was started at Kaunas University of Technology in September 2002. This paper presents prerequisites for the establishment of the new M.Sc. programme , its aims, goals and structure as well as the relation of different subjects of the programme to the concept of industrial ecology.     

Multifunctional Magnetic Optical Sensor Particles with Tunable Sizes for Monitoring Metabolic Parameters and as a Basis for Nanotherapeutics

Magnetic optical sensor particles with multifunctional cores and shells are synthesized via a facile nanoprecipitation method and the subsequent modification of the particle shell. The hydrophobic particle core includes optical oxygen indicators, a light harvesting system, photosensitizers, and magnetic nanoparticles. Further functionalities are introduced by modifying the shell with enzymes, antibodies, multiple layers of polyelectrolytes, stimuli‐responsive polymers, and luminescent indicator dyes. The hydrodynamic diameter is tunable by varying different precipitation parameters.     

Cleaner production financing: possibilities and barriers

There are several players who could facilitate the promotion of cleaner production (CP) by establishing an effective financing mechanism; for instance, government, international assistance bodies, banks and other financing organizations. In a few developing countries in South East Africa and Latin America and in Vietnam several international organizations, development banks and donors have initiated and implemented projects to facilitate the introduction of CP investments. Most projects have been in the form of technical assistance grants and training to industries and/or loans at below market rates from dedicated trust funds. Yet the present level of lending through such projects is far from sufficient to trigger widespread adoption of CP. Therefore, experts from The Institute of Environmental Engineering, Lithuania performed an investigation to create a CP development scheme for developing countries.     

Plasma platelet-activating factor levels in newborn infants with and without perinatal asphyxia: is it an additional marker of perinatal asphyxia?

We report a case of severe hyperthermia in a 6-month-old boy with a single ventricle, dextrocardia, asplenia, and transposition of the great arteries, during induction of anesthesia on three separate occasions. To our knowledge, this is the first case reported of repeated intraoperative hyperthermia not related to malignant hyperthermia, infection, neuroendocrine tumor, or iatrogenic causes (e.g., anticholinergic blockade or warming devices). The severe hyperthermia may be secondary to the medications given before and during induction and/or the stress of the induction. Among the induction medications given during the three episodes, fentanyl is the most likely contributing drug. Human data indicate that opioids increase the sweating threshold and decrease the vasoconstriction and shivering thresholds. The medications could cause a widening in the thermoregulation interthreshold and the stress could induce nonshivering thermogenesis.     

Comparison of food frequency questionnaires: the reduced Block and Willett questionnaires differ in ranking on nutrient intakes

Food frequency questionnaires, major tools in epidemiologic studies, are often criticized for biased and imprecise intake estimates. The aim of this study was to compare the performance of two widely used food frequency questionnaires, a reduced 60-item Block questionnaire and a 153-item Willett food frequency questionnaire, relative to three 24-hour recalls administered by telephone. The dietary data were collected in 1991 from a group of healthy women age 25-49 years (n=101) during the baseline period of a weight-loss intervention study in Minneapolis, Minnesota. Total energy and macro- and micronutrient intakes were compared across methods by using four analytic approaches: comparison of means and correlation coefficients, regression analysis, and estimation of percent agreement between each questionnaire and recalls. The Block instrument showed an overall underestimation bias, but was more successful in categorizing individuals on percent energy from fat and carbohydrate intakes than was the Willett instrument. The Willett instrument showed no overall underestimation bias and was more successful in classifying individuals on vitamin A and calcium intakes. Diverging performance characteristics of diet assessment methods have an implication for the design of studies, interpretation of results, and comparison of findings across studies.