Cytokines and PGE2 modulate the phagocytic function of the beta-glucan receptor in macrophages

Under serum-free conditions the beta-glucan receptor of mouse macrophages mediates phagocytosis of beta-1,3-D-glucan-coated microbeads (diameter 2 microns). IFN-gamma increases the phagocytic function of the beta-glucan receptor in a dose-dependent manner, giving the plateau level at 100 U/ml. Maximum activity appears 9 h after addition of IFN-gamma to the cells. The effect disappears within 24 h. The effect of IFN-gamma may be a result of augmented receptor synthesis since treatment with cycloheximide reduces the phagocytosis. IL-1 also increases the phagocytic function of the beta-glucan receptor giving a dose-dependent response and with the plateau level reached at 10 U/ml. Maximum activity is found 4 h after addition of IL-1 to macrophages. The effect disappears within 24 h. TNF does not alter the phagocytic function of the beta-glucan receptor, but TNF together with IL-1 prolongs the effect of IL-1. PGE2 reduces the phagocytic function of the beta-glucan receptor. Maximum reduction is achieved with 8 ng/ml. Time-course studies show the lowest phagocytic activity 9 h after addition of PGE2 to the cells.     

The effect of packaging materials and oxygen on the colour stability of sliced bologna

The aim of the study was to determine the effect of packaging materials with different oxygen permeability, residual oxygen concentration in the package and light upon discoloration of the surface of sliced bologna. The packaging material caused significant differences in the discolouration of vacuum-packed, sliced bologna. The surface colour of sliced bologna packed in films with an oxygen transmission rate lower than 10cm³/m²/24h/atm was not affected by illuminated storage. Packages of sliced bologna with 0% oxygen in the head space showed good colour stability after 28 days of illuminated storage at 4 C. The discolouration of bologna was almost directly proportional to oxygen concentration in the package. Bologna stored in a high oxygen concentration developed more off-odour; 1% and 2% oxygen in the packages caused higher worst spot colour, discolouration and off-odour scores after 3 days of storage.     

NanoSIMS Analysis of Trace Element Segregation during the Al-Si Eutectic Reaction

The purpose of the present article was to test, for the first time, the potential of the NanoSIMS for quantifying the microscale spatial distribution of trace elements in aluminum alloys. As a suitable test case, two variants of an as-cast industrial A356 alloy have been chosen and analyzed quantitatively. The results show that Sr segregates preferentially to the α-Si particles rather than to the Al matrix. The Na segregates preferentially to α-Si, but in contrast to Sr, Na is inhomogeneously distributed in the particles and tends to accumulate at parts of their surfaces. The Ca segregates preferentially to the Al matrix and was not found in α-Si. This suggests that impurity-induced twinning is probably not the mechanism responsible for the flake-to-fibrous transition observed in Ca-modified Al-Si-alloys. The P was difficult to analyze as the ³1P-peak was close to the peak of the molecule fragment ³1Si + ¹H. The complication can probably be resolved in future studies. The present work demonstrated that NanoSIMS is a tool with great potential for providing new insight into microscale trace element segregation in Al alloys. This article is based on a presentation made in the symposium entitled “Solidification Modeling and Microstructure Formation: In Honor of Prof. John Hunt,” which occurred March 13–15, 2006, during the TMS Spring Meeting in San Antonio, Texas, under the auspices of the TMS Materials Processing and Manufacturing Division, Solidification Committee.     

Inhibition of establishment and growth of mouse liver metastases after treatment with interferon gamma and beta-1,3-D-glucan

Bruton's tyrosine kinase (Btk) is a non-receptor protein tyrosine kinase (PTK) that is expressed in all haemopoietic lineages except mature T cells and plasma cells. Despite the broad range of expression. mutations that inactivate this molecule affect primarily the development of the B-cell lineage. As a PTK, Btk could potentially be involved directly or indirectly in the processes that relate to the malignant transformation of all the cell lineages where this molecule is expressed. Previous studies have failed to demonstrate mutations in patients with B-cell origin acute lymphoblastic leukaemia (ALL). We have utilized a recently developed method that enables the rapid and convenient detection of mutations at the cDNA level, namely, the non-isotopic RNase cleavage assay (NIRCA) to analyse Btk sequences from 27 patients with different types of acute myeloid leukaemia (AML). The only alteration that we observed was a polymorphism at position 2031. This polymorphism has already been seen in previous studies. Furthermore, using the same methodology, we identified the Btk mutations in six XLA (X-linked agammaglobulinaemia) patients. Our results, although they do not exclude the involvement of Btk mutations in the development or progression of some type of AML, nevertheless suggest that such mutations do not constitute a major co-factor in the development of myeloid malignancies.     

Characterization and cytokine-stimulating activities of acidic heteroglycans from Tremella fuciformis

Four acidic heteroglycans, T2a-T2d, were isolated from the body of Tremella fuciformis Berk. They contained 1.9%-2.9% of acetyl groups and were composed of mannose (Man), glucuronic acid (GlcA), and small amounts of xylose (Xyl), glucose (Glc), and fucose (Fuc). According to methylation analysis they had a mannan backbone consisting of 3-linked Man, and side chains containing glucosyl, mannosyl, fucosyl, xylosyl, and glucuronic acid residues. The side chains were attached through O-2, O-4, or O-6 in about 40 percent of backbone mannosyl residues. Molecular masses of the four polysaccharides were 410, 250, 34, and 20 kDa, respectively. T2a-T2d induced human monocytes to produce interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor (TNF) in vitro. The products of Smith degradation (T2a-S) and lithium degradation (T2a-L) of T2a and the product of deacetylation (T2b-D) of T2b also induced monocytes to secret IL-1 as efficiently as the original polysaccharides, indicating that xylosyl and glucuronic acid residues as well as acetyl groups were not important to promote the cytokine-stimulating activity.     

Biological effects of the immunomodulator beta 1-3D polyglucose are strongly potentiated by conjugation to biodegradable microbeads

It is demonstrated that the biological effects of the immunomodulator beta 1-3D polyglucose, when covalently linked to polymethacrylate or biodegradable albumin microbeads, are strongly potentiated. The potentiation is recorded as an increased protection effect of the conjugates in Escherichia coli sepsis in mice, and as increased IL-1 production by murine macrophages in vitro.     

Nordic Safety Climate Questionnaire (NOSACQ-50): A new tool for diagnosing occupational safety climate

Although there is a plethora of questionnaire instruments for measuring safety climate or culture, very few have proven able to present a factor structure that is consistent in different contexts, and many have a vague theoretical grounding. The Nordic Safety Climate Questionnaire (NOSACQ-50) was developed by a team of Nordic occupational safety researchers based on organizational and safety climate theory, psychological theory, previous empirical research, empirical results acquired through international studies, and a continuous development process. Safety climate is defined as workgroup members’ shared perceptions of management and workgroup safety related policies, procedures and practices. NOSACQ-50 consists of 50 items across seven dimensions, i.e. shared perceptions of: 1) management safety priority, commitment and competence; 2) management safety empowerment; and 3) management safety justice; as well as shared perceptions of 4) workers’ safety commitment; 5) workers’ safety priority and risk non-acceptance; 6) safety communication, learning, and trust in co-workers’ safety competence; and 7) workers’ trust in the efficacy of safety systems. Initial versions of the instrument were tested for validity and reliability in four separate Nordic studies using native language versions in each respective Nordic country. NOSACQ-50 was found to be a reliable instrument for measuring safety climate, and valid for predicting safety motivation, perceived safety level, and self-rated safety behavior. The validity of NOSACQ-50 was further confirmed by its ability to distinguish between organizational units through detecting significant differences in safety climate.

Relevance to industry

NOSACQ-50 will enable comparative studies of safety climate between and within companies, industries and countries. It is suitable for research purposes as well as for practical use in evaluating safety climate status, as a diagnostic tool, and in evaluating the effect of safety climate interventions.