Katrina Nordström

Pitted keratolysis: the role of Micrococcus sedentarius

Though pitted keratolysis of the foot is generally viewed to be caused by bacteria, there is confusion regarding the identity of the causative organism. Species of Corynebacterium, Actinomyces, Dermatophilus, and Micrococcus have been proposed by various investigators. We have studied eight cases of pitted keratolysis and have cultured an organism identified as Micrococcus sedentarius on the basis of colonial morphology, micromorphology, biochemical reactions, and chemical analysis of whole-cell components. Furthermore, pitted keratolysis was produced experimentally in a human volunteer by applying M sedentarius under an occlusive dressing onto the surface of the heel.

Microbial ecology of interdigital infections of toe web spaces

The microbial flora of normal and macerated interdigital toe web spaces was qualitatively and quantitatively identified in 77 patients. Dermatophyte fungi were recovered from 11% of normal patients compared with a 31% recovery from patients with macerated interspaces. Macerated interspaces were characterized by a greater recovery of organisms with pathogenic potential, with Staphylococcus aureus recovered from 36% of patients, Micrococcus sedentarius in 37%, Brevibacterium epidermidis in 54%, Corynebacterium minutissimum in 69%, and Pseudomonas species in 26%. The bacterial flora of macerated interspaces showed a significantly higher incidence of resistance to multiple antibiotics, and the recovery of antibiotic-resistant bacteria correlated with the recovery of dermatophytes that produce penicillin-like substances. The results of this study support the hypothesis that overgrowth of the resident bacterial population determines the severity of interdigital toe-web infections.

Mitochondrial function and energy metabolism in umbilical cord blood- and bone marrow-derived mesenchymal stem cells.

Human mesenchymal stem cells (hMSCs) are an attractive choice for a variety of cellular therapies. hMSCs can be isolated from many different tissues and possess unique mitochondrial properties that can be used to determine their differentiation potential. Mitochondrial properties may possibly be used as a quality measure of hMSC-based products. Accordingly, the present work focuses on the mitochondrial function of hMSCs from umbilical cord blood (UCBMSC) cells and bone marrow cells from donors younger than 18 years of age (BMMSC <18) and those more than 50 years of age (BMMSC >50). Changes of ultrastructure and energy metabolism during osteogenic differentiation in all hMSC types were studied in detail. Results show that despite similar surface antigen characteristics, the UCBMSCs had smaller cell surface area and possessed more abundant rough endoplasmic reticulum than BMMSC >50. BMMSC <18 were morphologically more UCBMSC-like. UCBMSC showed dramatically higher mitochondrial-to-cytoplasm area ratio and elevated superoxide and manganese superoxide dismutase (MnSOD) levels as compared with BMMSC >50 and BMMSC <18. All hMSCs types showed changes indicative of mitochondrial activation after 2 weeks of osteogenic differentiation, and the increase in mitochondrial-to-cytoplasm area ratio appears to be one of the first steps in the differentiation process. However, BMMSC >50 showed a lower level of mitochondrial maturation and differentiation capacity. UCBMSCs and BMMSCs also showed a different pattern of exocytosed proteins and glycoproteoglycansins. These results indicate that hMSCs with similar cell surface antigen expression have different mitochondrial and functional properties, suggesting different maturation levels and other significant biological variations of the hMSCs. Therefore, it appears that mitochondrial analysis presents useful characterization criteria for hMSCs intended for clinical use.

Identification of key success factors of functional dairy foods product development

Abstract The present study elucidates key success factors influencing the product development of functional dairy foods and examines if the studied products can be categorized as potential breakthrough products primarily in a domestic market. General conclusions are also made with reference to functional foods development in the international setting. Three functional dairy foods were studied with specific emphasis on the key success factors influencing length and timing of individual product development phases on the total length of product development. Key factors which were identified as being the most critical were (1) the specificity and action mechanism of the added health benefit of the final product, (2) the range of new product or process alternatives, (3) the selection of the consumer target group and, (4) legal and marketing issues.

CD200 Positive Human Mesenchymal Stem Cells Suppress TNF-Alpha Secretion from CD200 Receptor Positive Macrophage-Like Cells

Human mesenchymal stem cells (hMSCs) display immunosuppressive properties in vitro and the potential has also been transferred successfully to clinical trials for treatment of autoimmune diseases. OX-2 (CD200), a member of the immunoglobulin superfamily, is widely expressed in several tissues and has recently been found from hMSCs. The CD200 receptor (CD200R) occurs only in myeloid-lineage cells. The CD200-CD200R is involved in down-regulation of several immune cells, especially macrophages. The present study on 20 hMSC lines shows that the CD200 expression pattern varied from high (CD200Hi) to medium (CD200Me) and low (CD200Lo) in bone marrow-derived mesenchymal stem cell (BMMSC) lines, whereas umbilical cord blood derived mesenchymal stem cells (UCBMSCs) were constantly negative for CD200. The role of the CD200-CD200R axis in BMMSCs mediated immunosuppression was studied using THP-1 human macrophages. Interestingly, hMSCs showed greater inhibition of TNF-α secretion in co-cultures with IFN-γ primed THP-1 macrophages when compared to LPS activated cells. The ability of CD200Hi BMMSCs to suppress TNF-α secretion from IFN-γ stimulated THP-1 macrophages was significantly greater when compared to CD200Lo whereas UCBMSCs did not significantly reduce TNF-α secretion. The interference of CD200 binding to the CD200R by anti-CD200 antibody weakened the capability of BMMSCs to inhibit TNF-α secretion from IFN-γ activated THP-1 macrophages. This study clearly demonstrated that the efficiency of BMMSCs to suppress TNF-α secretion of THP-1 macrophages was dependent on the type of stimulus. Moreover, the CD200-CD200r axis could have a previously unidentified role in the BMMSC mediated immunosuppression.

Creativity and inspiration for problem solving in engineering education

Problem solving is a critical skill for engineering students and essential to development of creativity and innovativeness. Essential to such learning is an ease of communication and allowing students to address the issues at hand via the terminology, attitudes, humor and empathy, which is inherent to their frame of mind as novices, without the attempt to have to be the expert. Deep learning of scientific fact can be facilitated by using non-conventional tools for teaching, learning and presentation such as drama, video, posters, model making and other similar means. It may be time to break free of the PowerPoint tradition to generate successful approaches for establishing student engagement and maintaining such engagement.

Toward a nontoxic poison: Current trends in (European union) biocides regulation

ABSTRACT The number of products containing biocides is increasing at the same time as the number of available biocides is decreasing. Biocides are biologically active chemicals with a vast area of applications where demands for maintaining product quality by use of biocides presents a major challenge for developers striving to meet emerging environmental concerns and fulfilling criteria for eco-labeled consumer products. Tightening regulations have, however, led to stagnation in the current development of new biocide chemistries, and the “nontoxic poison” has yet to be formulated. Accordingly, the present article presents a critical overview of European Union regulation of biocides and their usage and of some of the future challenges for meeting demands for environmentally safe products and processes in which biocides are used. The Biocidal Product Directive, which is presently implemented, is one focus in the present article. Regulations of environmental, health, and safety (EHS) risk classifications and their role in the future development of biocide-containing products are also discussed. Studying the biocide dilemma may provide tools for the chemical industry as whole for proactive anticipation of the effect of emerging regulatory demands on product development.

Copper as an antibacterial material in different facilities

The present study was performed in real life settings in different facilities (hospital, kindergarten, retirement home, office building) with copper and copper alloy touch surface products (floor drain lids, toilet flush buttons, door handles, light switches, closet touch surfaces, corridor hand rails, front door handles and toilet support rails) in parallel to reference products. Pure copper surfaces supported lower total bacterial counts (16 ± 45 vs 105 ± 430 CFU cm−2, n = 214, P < 0·001) and a lower occurrence of Staphylococcus aureus (2·6 vs 14%, n = 157, P < 0·01) and Gram‐negatives (21 vs 34%, n = 214, P < 0·05) respectively than did reference surfaces, whereas the occurrence of enterococci (15%, n = 214, P > 0·05) was similar. The studied products could be assigned to three categories according to their bacterial loads as follows (P < 0·001): floor drain lids (300 ± 730 CFU cm−2, n = 32), small area touch surfaces (8·0 ± 7·1 to 62 ± 160 CFU cm−2, n = 90) and large area touch surfaces (1·1 ± 1·1 to 1·7 ± 2·4 CFU cm−2, n = 92). In conclusion, copper touch surface products can function as antibacterial materials to reduce the bacterial load, especially on frequently touched small surfaces.

Emergence of a dominant design in probiotic functional food development

This study explores technological factors influencing the development of functional food products. The specific aim was to investigate if the concept of a dominant design holds true for functional foods. By using consumer acceptance as the measure of product dominance, it is postulated that market pressure inherent to functional foods becomes established by the perceived value to consumers. This value is due to the inherent and documented health advantages, taste, user convenience and competitive price. Switching costs, which create barriers to entry, for functional foods are due to the establishment of a technological solution, patenting, meeting regulatory approval and brand assets in connection to marketing. It is also postulated that in the development of functional foods, a product innovation phase leads into process innovation alternatives. These alternatives arise from different precursors of dominant designs.

Services for distribution of tissue engineering products and therapies

Purpose – Tissue engineering (TE) offers treatments for chronic, life threatening, degenerative illnesses and possibilities for restoring cellular or organ functions that have been lost due to injuries or hereditary conditions. However, a prerequisite for the use of TE products as part of future therapies is the development of strategies for safe and efficient supply chain management and versatile services spanning from product development to a follow‐up period of possibly decades. The present study aims to explore the future needs for services and extended supply chains for safe delivery of health care, procurement, distribution and long‐term follow‐up of TE products and therapies.Design/methodology/approach – Studies in operational disciplines and coordination systems for different types of supply chains and service networks are used to formulate a framework for developing services throughout product lifecycle. Case examples of TE products are presented to demonstrate complexity, microbial risks, servic...