Season, dietary factors, and physical activity modify 25-hydroxyvitamin D concentration during pregnancy.

PURPOSE: The objectives of this cross-sectional study were to define maternal and umbilical cord blood (UCB) 25-hydroxyvitamin D (25(OH)D) to characterize maternal factors modifying 25(OH)D during pregnancy and predict UCB 25(OH)D in two subgroups with Declined [Δ25(OH)D <0 nmol/l] and Increased [Δ25(OH)D >0 nmol/l] 25(OH)D concentration. METHODS: A complete dataset was available from 584 women. 25(OH)D was determined at gestational weeks 6-13 and in UCB. Baseline characteristics were collected retrospectively using questionnaires. Δ25(OH)D was calculated as UCB 25(OH)D-early pregnancy 25(OH)D. Dietary patterns were generated with principal component analysis. Multivariate regression models were applied. RESULTS: Vitamin D deficiency was scarce, since only 1% had 25(OH)D concentration <50 nmol/l both in early pregnancy and in UCB. Shared positive predictors of UCB 25(OH)D in the subgroups of Declined and Increased, were early pregnancy 25(OH)D (P < 0.001) and supplemental vitamin D intake (P < 0.04). For the Increased subgroup summer season at delivery (P = 0.001) and "sandwich and dairy" dietary pattern characterized with frequent consumption of vitamin D fortified margarine and milk products (P = 0.009) were positive predictors of UCB 25(OH)D. Physical activity (P = 0.041) and maternal education (P = 0.004) were additional positive predictors in the Declined group CONCLUSIONS: Maternal and newborn vitamin D status was sufficient, thus public health policies in Finland have been successful. The key modifiable maternal determinants for 25(OH)D during pregnancy, and of the newborn, were supplemental vitamin D intake, frequent consumption of vitamin D fortified foods, and physical activity.

Dietary phosphorus intake is negatively associated with bone formation among women and positively associated with some bone traits among men-a cross-sectional study in middle-aged Caucasians.

High dietary phosphorus (P) intake has acute negative effects on calcium (Ca) and bone metabolism, but long-term clinical data are contradictory. We hypothesized that high P intake is associated with impaired bone health as suggested by earlier short-term studies on bone metabolism. In this cross-sectional study, we investigated associations between dietary P intake, bone traits in the radius and tibia, and bone turnover in a population-based sample of 37- to 47-year-old Caucasian premenopausal women (n=333) and men (n=179) living in Southern Finland (60°N). We used various regression models in an "elaboration approach" to elucidate the role of P intake in bone traits and turnover. The addition of relevant covariates to the models mainly removed the significance of P intake as a determinant of bone traits. In the final regression model (P intake, weight, height, age, Ca intake, serum 25-hydroxyvitamin D, physical activity, smoking, contraceptive use in women), P intake was slightly positively associated only with bone mineral content and cross-sectional cortical bone area in the tibia of men. Among women, inclusion of Ca removed all existing significance in the crude models for any bone trait. In women P intake was negatively associated with the bone formation marker serum intact pro-collagen type I amino-terminal propeptide, whereas no association was present between P intake and bone turnover in men. In conclusion, these findings disagree with the hypothesis; P intake was not deleteriously associated with bone traits; however, P intake may negatively contribute to bone formation among women.

Phosphorus and nitrogen fluxes carried by 21 Finnish agricultural rivers in 1985-2006.

The Finnish Agri-Environmental Programme aims to reduce nutrient load to waters. Using national monitoring data, we estimated the agricultural load (incl. natural background) of total phosphorus (TP) and total nitrogen (TN) transported by 21 Finnish rivers to the northern Baltic Sea and analysed the flow-adjusted trends in the loads and concentrations from 1985 to 2006. We also related the loads to spatial and temporal patterns in catchment and agricultural characteristics. Agricultural load of TN increased, especially in the rivers discharging into the Bothnian Bay, while the load of TP decreased in most of the rivers, except those discharging into the Archipelago Sea. The trends may partly be related to a decrease in grassed area (TP, TN) and increased mineralisation (TN), but the available data on catchment and agricultural characteristics did not fully explain the observed pattern. Our study showed that data arising from relatively infrequent monitoring may prove useful for analysing long-term trend. The mutual correlation among the explaining variables hampered the analysis of the load generating factors.

A multi-scale comparison of dissolved Al, Fe and S in a boreal acid sulphate soil.

Acid sulphate (AS) soils are most prevalent in the tropics, but the acidic discharge from cultivated AS soils also threatens water bodies under boreal conditions. Feasible options to reduce the acid load are needed. In this study, the groundwater of an AS field was monitored for 3.5 years, and the efficiency of waterlogging in mitigating the environmental risks caused by acidic discharge was investigated in a 2.5-year experiment with 10 monolithic lysimeters taken from the same field. In order to unravel the transferability of the results from lysimeters to the field scale, the Al, Fe and S concentrations in discharge water from the lysimeters were compared with those in the groundwater of the AS field (pedon and field scale), and in pore water (pedon and horizon scale). In the waterlogged bare lysimeters (HWB), the Al, Fe and S concentrations in discharge waters were broadly similar to those measured in the groundwater and followed the changes in the pore water. In the waterlogged cropped (reed canary grass, Phalaris arundinacea) lysimeters (HWC), in contrast, the discharge waters were markedly higher in Fe and lower in Al than the groundwater in the field. This outcome was attributable to the reduction of Fe(3+) to the more soluble Fe(2+) and the reduction-induced increase in pH, which enhanced the formation of Al(3+) hydroxy species. Lowering of the water table (LWC) caused soil ripening, which resulted in increased saturated hydraulic conductivity and porosity and enhanced the oxidation of sulphidic materials and acid formation. The responses of Al, Fe and S in drainage waters from HWC and LWC lysimeters resembled previous findings in AS soils. Based on this and the similarity between dissolved element concentrations in the discharge water of HWB lysimeters and groundwater in the field, we conclude that our monolithic lysimeters yielded realistic results concerning the efficiency of various methods in mitigating environmental risks related to cultivated AS soils.

Phosphorylated ß-catenin localizes to centrosomes of neuronal progenitors and is required for cell polarity and neurogenesis in developing midbrain.

ß-catenin has well-established functions in cell growth and differentiation as part of the Wnt signaling pathway and in regulation of cellular adhesion with E-cadherin. Here we studied its significance in midbrain development by temporally controlled deletion of ß-catenin allowing simultaneous analysis of complete (ß-cat-null) and partial (ß-cat-low) loss-of-function phenotypes in progenitor cells. ß-cat-null cells did not contain centrosomes or a microtubule network and were unpolarized forming delaminated bulges. ß-cat-low cells displayed defects in the orientation of the mitotic spindle, increased asymmetric cell divisions and premature differentiation in absence of alterations in polarity or adhesion. The spindle defect was associated with decreased centrosomal S33/S34/T41 phosphorylated ß-catenin (p-ß-cat) and centrosomal and microtubule defects. Interestingly, neural progenitor cells in mice expressing only unphosphorylatable ß-catenin share several phenotypes with ß-catenin loss-of-function mice with defects in microtubules and polarity. The results demonstrate a novel function for p-ß-cat in maintaining neuroepithelial integrity and suggest that centrosomal p-ß-cat is required to maintain symmetric cleavages and polarity in neural progenitors.

Comparison of results for weight-adjusted and fixed-amount bronchoalveolar lavage techniques in healthy Beagles.

OBJECTIVE: To compare recovery of epithelial lining fluid (ELF) in bronchoalveolar lavage fluid (BALF) by use of weight-adjusted or fixed-amount volumes of lavage fluid in dogs. ANIMALS: 13 healthy Beagles. PROCEDURES: Dogs were allocated to 2 groups. In 1 group, the right caudal lung lobe was lavaged on the basis of each dog's weight (2 mL/kg, divided into 2 aliquots) and the left caudal lung lobe was lavaged with a fixed amount of fluid (50 mL/dog, divided into 2 aliquots). In the second group, the right and left caudal lung lobes were lavaged by use of the fixed-amount and weight-adjusted techniques, respectively. The BALF was collected by use of bronchoscopy. A recovery percentage ≥ 40% was required. The proportion of ELF was calculated by use of the following equation: (concentration of urea in BALF/concentration of urea in serum) × 100. RESULTS: Mean ± SD proportion of ELF in BALF was 2.28 ± 0.39% for the weight-adjusted technique and 2.89 ± 0.89% for the fixed-amount technique. The SDs between these 2 techniques differed significantly (calculated by comparing 2 covariance structures [unstructured and compound symmetry] in a repeated-measures mixed ANOVA). CONCLUSIONS AND CLINICAL RELEVANCE: The findings strongly suggested that use of a weight-adjusted bronchoalveolar lavage technique provided a more uniform ELF recovery, compared with that for a fixed-amount bronchoalveolar lavage technique, when urea was used as a marker of dilution. A constant ELF fraction can facilitate more accurate comparisons of cellular and noncellular constituents in BALF among patients of various sizes.

Reliability and validity of a visual analogue scale used by owners to measure chronic pain attributable to osteoarthritis in their dogs.

OBJECTIVE: To assess validity and reliability for a visual analogue scale (VAS) used by owners to measure chronic pain in their osteoarthritic dogs. SAMPLE: 68, 61, and 34 owners who completed a questionnaire. PROCEDURES: Owners answered questionnaires at 5 time points. Criterion validity of the VAS was evaluated for all dogs in the intended-to-treat population by correlating scores for the VAS with scores for the validated Helsinki Chronic Pain Index (HCPI) and a relative quality-of-life scale. Intraclass correlation was used to assess repeatability of the pain VAS at 2 baseline evaluations. To determine sensitivity to change and face validity of the VAS, 2 blinded, randomized control groups (17 dogs receiving carprofen and 17 receiving a placebo) were analyzed over time. RESULTS: Significant correlations existed between the VAS score and the quality-of-life scale and HCPI scores. Intraclass coefficient (r = 0.72; 95% confidence interval, 0.57 to 0.82) for the VAS indicated good repeatability. In the carprofen and placebo groups, there was poor correlation between the 2 pain evaluation methods (VAS and HCPI items) at the baseline evaluation, but the correlation improved in the carprofen group over time. No correlation was detected for the placebo group over time. CONCLUSIONS AND CLINICAL RELEVANCE: Although valid and reliable, the pain VAS was a poor tool for untrained owners because of poor face validity (ie, owners could not recognize their dogs' behavior as signs of pain). Only after owners had seen pain diminish and then return (after starting and discontinuing NSAID use) did the VAS have face validity.

Effects of polarization in the presence and absence of biocides on biofilms in a simulated paper machine water.

The antifouling potential of electric polarization combined and not combined with biocides was studied in nonsaline warm water with high organic content. Deinococcus geothermalis is a bacterium known for forming colored biofilms in paper machines and for its persistence against cleaning and chemical treatments. When D. geothermalis biofilms grown for 24 h in simulated paper machine water were exposed to cathodic or cathodically weighted pulsed polarization at least 60% (P < 0.05) of the biofilms were removed from stainless steel (AISI 316L). Biofilm removal by 25 ppm (effective substances 5-25 ppm) of oxidizing biocides (bromochloro-5,5-dimethylhydantoin, 2,2-dibromo-2-cyanoacetamide, peracetic acid) increased to 70% when combined with cathodically weighted pulsed polarization. Using a novel instrument that allows real-time detection of reactive oxygen species (ROS) we showed that the polarization program effective in antifouling generated ROS in a pulsed manner on the steel surface. We thus suggest that the observed added value of oxidative biocides combined with polarization depended on ROS. This suggestion was supported by the finding that a reductive biocide, methylene bisthiocyanate, counteracted the antifouling effect of polarization.

Biofilm-forming bacteria with varying tolerance to peracetic acid from a paper machine.

Biofilms cause runnability problems in paper machines and are therefore controlled with biocides. Peracetic acid is usually effective in preventing bulky biofilms. This study investigated the microbiological status of a paper machine where low concentrations (≤ 15 ppm active ingredient) of peracetic acid had been used for several years. The paper machine contained a low amount of biofilms. Biofilm-forming bacteria from this environment were isolated and characterized by 16S rRNA gene sequencing, whole-cell fatty acid analysis, biochemical tests, and DNA fingerprinting. Seventy-five percent of the isolates were identified as members of the subclades Sphingomonas trueperi and S. aquatilis, and the others as species of the genera Burkholderia (B. cepacia complex), Methylobacterium, and Rhizobium. Although the isolation media were suitable for the common paper machine biofoulers Deinococcus, Meiothermus, and Pseudoxanthomonas, none of these were found, indicating that peracetic acid had prevented their growth. Spontaneous, irreversible loss of the ability to form biofilm was observed during subculturing of certain isolates of the subclade S. trueperi. The Sphingomonas isolates formed monoculture biofilms that tolerated peracetic acid at concentrations (10 ppm active ingredient) used for antifouling in paper machines. High pH and low conductivity of the process waters favored the peracetic acid tolerance of Sphingomonas sp. biofilms. This appears to be the first report on sphingomonads as biofilm formers in warm water using industries.

FGF signaling gradient maintains symmetrical proliferative divisions of midbrain neuronal progenitors.

For the correct development of the central nervous system, the balance between self-renewing and differentiating divisions of the neuronal progenitors must be tightly regulated. To maintain their self-renewing identity, the progenitors need to retain both apical and basal interfaces. However, the identities of fate-determining signals which cells receive via these connections, and the exact mechanism of their action, are poorly understood. The conditional inactivation of Fibroblast growth factor (FGF) receptors 1 and 2 in the embryonic mouse midbrain-hindbrain area results in premature neuronal differentiation. Here, we aim to elucidate the connection between FGF signaling and neuronal progenitor maintenance. Our results reveal that the loss of FGF signaling leads to downregulation of Hes1 and upregulation of Ngn2, Dll1, and p57 in the ventricular zone (VZ) cells, and that this increased neurogenesis occurs cell-autonomously. Yet the cell cycle progression, apico-basal-polarity, cell-cell connections, and the positioning of mitotic spindle in the mutant VZ appear unaltered. Interestingly, FGF8-protein is highly concentrated in the basal lamina. Thus, FGFs may act through basal processes of neuronal progenitors to maintain their progenitor status. Indeed, midbrain neuronal progenitors deprived in vitro of FGFs switched from symmetrical proliferative towards symmetrical neurogenic divisions. We suggest that FGF signaling in the midbrain VZ is cell-autonomously required for the maintenance of symmetrical proliferative divisions via Hes1-mediated repression of neurogenic genes.

Low calcium:phosphorus ratio in habitual diets affects serum parathyroid hormone concentration and calcium metabolism in healthy women with adequate calcium intake.

Excessive dietary P intake alone can be deleterious to bone through increased parathyroid hormone (PTH) secretion, but adverse effects on bone increase when dietary Ca intake is low. In many countries, P intake is abundant, whereas Ca intake fails to meet recommendations; an optimal dietary Ca:P ratio is therefore difficult to achieve. Our objective was to investigate how habitual dietary Ca:P ratio affects serum PTH (S-PTH) concentration and other Ca metabolism markers in a population with generally adequate Ca intake. In this cross-sectional analysis of 147 healthy women aged 31-43 years, fasting blood samples and three separate 24-h urinary samples were collected. Participants kept a 4-d food record and were divided into quartiles according to their dietary Ca:P ratios. The 1st quartile with Ca:P molar ratio < or = 0.50 differed significantly from the 2nd (Ca:P molar ratio 0.51-0.57), 3rd (Ca:P molar ratio 0.58-0.64) and 4th (Ca:P molar ratio > or = 0.65) quartiles by interfering with Ca metabolism. In the 1st quartile, mean S-PTH concentration (P = 0.021) and mean urinary Ca (U-Ca) excretion were higher (P = 0.051) than in all other quartiles. These findings suggest that in habitual diets low Ca:P ratios may interfere with homoeostasis of Ca metabolism and increase bone resorption, as indicated by higher S-PTH and U-Ca levels. Because low habitual dietary Ca:P ratios are common in Western diets, more attention should be focused on decreasing excessively high dietary P intake and increasing Ca intake to the recommended level.

Algal-available phosphorus entering the Gulf of Finland as estimated by algal assays and chemical analyses.

Algal-available phosphorus (Paa) in river water and wastewater entering the Gulf of Finland (a Baltic Sea sub-basin) was estimated by a fresh-water and a brackish-water modification of the dual-culture algal assay. The assay results were further related to those obtained by routine chemical analyses. According to the brackish-water assay, an average of 44% (range, 9-88%) of total phosphorus (TP) in water samples from the Neva, Kymijoki, and Narva rivers consisted of Paa, whereas the mean value given by the fresh-water assay was 22% (range, 0-48%). Phaeodactylum tricornutum Bohlin, which was used as the test alga in the brackish-water assay, had higher phosphoesterase activity and P affinity than did Pseudokirchneriella subcapitata Korschikov, which was used in the fresh-water assay. This difference may explain the higher values of Paa shown by the brackish-water assay. Of the analytical P forms, total dissolved P best approximated, yet underestimated, the Paa in river water samples. As for the biologically purified wastewaters of the city of St. Petersburg, both assays suggested that about 80% of TP (range, 59-103%) was available. That the assays gave similar results was probably due to the fact that most of the P in the wastewater samples was in the form of readily available dissolved reactive P. In untreated urban wastewaters, the mean proportion of Paa in TP was 46% (range, 19-76%). Although the true Paa may not be obtained by any assay, our findings corroborate the view that severe underestimation may occur if the test conditions are suboptimal for the release and uptake of P.

Psychometric testing of the Helsinki chronic pain index by completion of a questionnaire in Finnish by owners of dogs with chronic signs of pain caused by osteoarthritis.

OBJECTIVE: To determine the validity, reliability, and sensitivity of a published chronic pain index by completion of a questionnaire in Finnish by owners of dogs with chronic signs of pain caused by osteoarthritis. ANIMALS: 61 client-owned dogs with osteoarthritis. PROCEDURES: Validity, internal consistency, and repeatability testing of the questionnaire were evaluated by completion of questions in Finnish by owners of 61 dogs; the questionnaire was named the Helsinki chronic pain index (HCPI). Sensitivity testing of the questionnaire was determined from data of 2 smaller groups of dogs treated with carprofen (n = 17) or placebo (17). Owners completed the questionnaire 5 times during a 16-week period. Psychometric properties of the HCPI were evaluated. RESULTS: Principal component analysis yielded only a single stable component, indicating that the HCPI was best explained as an 11-item single construct index of chronic pain. Changes in the HCPI correlated well with change in quality of life and with change in the mobility visual analogue scale (r = 0.72 and r = 0.67, respectively), indicating a high predictive validity. Internal consistency (Cronbach A value = 0.82) and test-retest reliability (intraclass correlation coefficient = 0.84 for items and 0.92 for the HCPI) were high. Changes in scores (from baseline to treatment and back to no treatment) between the carprofen treatment group and placebo control group were significant, indicating high sensitivity. CONCLUSIONS AND CLINICAL RELEVANCE: The Finnish version of the HCPI provided a valid, reliable, and responsive tool for assessment of response to treatment in dogs with osteoarthritis.

Food allergy alters jejunal circular muscle contractility and induces local inflammatory cytokine expression in a mouse model.

BACKGROUND: We hypothesized that food allergy causes a state of non-specific jejunal dysmotility. This was tested in a mouse model. METHODS: Balb/c mice were epicutaneously sensitized with ovalbumin and challenged with 10 intragastric ovalbumin administrations every second day. Smooth muscle contractility of isolated circular jejunal sections was studied in organ bath with increasing concentrations of carbamylcholine chloride (carbachol). Smooth muscle layer thickness and mast cell protease-1 (MMCP-1) positive cell density were assayed histologically. Serum MMCP-1 and immunoglobulins were quantified by ELISA, and mRNA expressions of IFN-gamma, IL-4, IL-6 and TGFbeta-1 from jejunal and ileal tissue segments were analyzed with quantitative real-time PCR. RESULTS: Ovalbumin-specific serum IgE correlated with jejunal MMCP-1+ cell density. In the allergic mice, higher concentrations of carbachol were required to reach submaximal muscular stimulation, particularly in preparations derived from mice with diarrhoea. Decreased sensitivity to carbachol was associated with increased expression of IL-4 and IL-6 mRNA in jejunum. Smooth muscle layer thickness, as well as mRNA of IFN-gamma and TGF-beta1 remained unchanged. CONCLUSION: In this mouse model of food allergy, we demonstrated a decreased response to a muscarinic agonist, and increased levels of proinflammatory IL-6 and Th2-related IL-4, but not Th1-related IFN-gamma mRNAs in jejunum. IgE levels in serum correlated with the number of jejunal MMCP-1+ cells, and predicted diarrhoea. Overall, these changes may reflect a protective mechanism of the gut in food allergy.

Habitual high phosphorus intakes and foods with phosphate additives negatively affect serum parathyroid hormone concentration: a cross-sectional study on healthy premenopausal women.

OBJECTIVE: Foods can contain natural phosphorus (NP) and phosphate-containing food additives (AP). The main objective of the present study was to investigate whether NP and AP of habitual diets differ in their effects on markers of Ca metabolism. We also investigated the impact of total habitual dietary P intake on markers of Ca metabolism. DESIGN: Cross-sectional study. Fasting blood samples were collected and participants kept a 4 d food record, from which dietary intake of total P and the consumption of NP (milk and cheese, excluding processed cheese) and AP (processed cheese) sources were calculated. Participants were divided into groups according to their NP- and AP-containing food consumption and into quartiles according to their total P intake. SETTING: Southern Finland. SUBJECTS: One hundred and forty-seven healthy premenopausal women aged 31-43 years. RESULTS: Relative to the lowest total dietary P quartile, mean serum parathyroid hormone (S-PTH) concentration was higher (P = 0.048, analysis of covariance (ANCOVA)) and the mean serum ionized Ca concentration lower (P = 0.016, ANCOVA) in the highest P intake quartile. Mean S-PTH concentrations were higher among participants who consumed processed cheese (P = 0.027, ANCOVA) and less milk and other cheese than processed cheese (P = 0.030, ANCOVA). CONCLUSIONS: High total habitual dietary P intake affected S-PTH unfavourably. Furthermore, phosphate additives may have more harmful effects on bone than other P sources, as indicated by higher mean S-PTH concentration among participants who consumed AP-containing foods. Because of the high dietary P intake and current upward trend in consumption of processed foods in Western countries, these findings may have important public health implications.

Wintertime vitamin D supplementation inhibits seasonal variation of calcitropic hormones and maintains bone turnover in healthy men.

Vitamin D is suggested to have a role in the coupling of bone resorption and formation. Compared with women, men are believed to have more stable bone remodeling, and thus, are considered less susceptible to the seasonal variation of calcitropic hormones. We examined whether seasonal variation exists in calcitropic hormones, bone remodeling markers, and BMD in healthy men. Furthermore, we determined which vitamin D intake is required to prevent this variation. Subjects (N = 48) were healthy white men 21-49 yr of age from the Helsinki area with a mean habitual dietary intake of vitamin D of 6.6 +/- 5.1 (SD) microg/d. This was a 6-mo double-blinded vitamin D intervention study, in which subjects were allocated to three groups of 20 microg (800 IU), 10 microg (400 IU), or placebo. Fasting blood samplings were collected six times for analyses of serum (S-)25(OH)D, iPTH, bone-specific alkaline phosphatase (BALP), and TRACP. Radial volumetric BMD (vBMD) was measured at the beginning and end of the study with pQCT. Wintertime variation was noted in S-25(OH)D, S-PTH, and S-TRACP (p < 0.001, p = 0.012, and p < 0.05, respectively) but not in S-BALP or vBMD in the placebo group. Supplementation inhibited the winter elevation of PTH (p = 0.035), decreased the S-BALP concentration (p < 0.05), but benefited cortical BMD (p = 0.09) only slightly. Healthy men are exposed to wintertime decrease in vitamin D status that impacts PTH concentration. Vitamin D supplementation improved vitamin D status and inhibited the winter elevation of PTH and also decreased BALP concentration. The ratio of TRACP to BALP shows the coupling of bone remodeling in a robust way. A stable ratio was observed among those retaining a stable PTH throughout the study. A daily intake of vitamin D in the range of 17.5-20 microg (700-800 IU) seems to be required to prevent winter seasonal increases in PTH and maintain stable bone turnover in young, healthy white men.

Environment driven cereulide production by emetic strains of Bacillus cereus.

The impacts of growth media and temperature on production of cereulide, the emetic toxin of Bacillus cereus, were measured for seven well characterised strains selected for diversity of biochemical and genetic properties and sources of origin. All strains carried cereulide synthase gene, ces, on a megaplasmid of ca. 200 kb and all grew up to 48-50 degrees C, but produced cereulide only up to 39 degrees C. On tryptic soy agar five strains, originating from foods, food poisonings and environment, produced highest amounts of cereulide at 23 to 28 degrees C, whereas two strains, from human faeces, produced cereulide similarly from 23 to 39 degrees C, with no clear temperature trend. These two strains differed from the others also by producing more cereulide on tryptic soy agar if supplemented with 5 vol.% of blood, whereas the other five strains produced similarly, independent on the presence of blood. On oatmeal agar only one strain produced major amounts of cereulide. On skim milk agar, raw milk agar, and MacConkey agar most strains grew well but produced only low amounts of cereulide. Three media components, the ratio [K+]:[Na+], contents of glycine and [Na+], appeared of significance for predicting cereulide production. Increase of [K+]:[Na+] (focal variable) predicted (P < 0.001) high cereulide provided that the contents of glycine and [Na+] (additional variables) were kept constant. The results show that growth medium and temperature up and downregulate cereulide production by emetic B. cereus in a complex manner. The relevance of the findings to production of cereulide in the gut and to the safety of amino acids as additives in foods containing live toxinogenic organisms is discussed.

Effects of processing on availability of total plant sterols, steryl ferulates and steryl glycosides from wheat and rye bran.

Rye and wheat bran are excellent natural sources of plant sterols in the diet. Their content, however, may vary according to processing. Thermal (roasting and heating in a microwave oven), mechanical (milling and cryogenic grinding), and enzymatic treatments (hydrolysis with xylanase or beta-glucanase or a mixture of these two enzymes) were performed, and their effect on sterol content, extractability of sterols and the characteristic steryl conjugates of cereals (steryl ferulates, steryl glycosides, and acylated steryl glycosides) were studied. Mechanical and enzymatic treatments increased the apparent sterol content, whereas aqueous processing without enzymes hindered the availability of total sterols, especially from rye bran. Changes were also seen in the amounts of steryl conjugates caused by the enzymatic treatments. On the basis of the results of this study, it can be speculated that a combination of fine particle size and enzymatic processing results in optimal sterol availability in cereal processing.

Effect of polysaccharide structure on mechanical and thermal properties of galactomannan-based films.

Films were prepared from guar gum and locust bean gum galactomannans. In addition, enzymatic modification was applied to guar gum to obtain structurally different galactomannans. Cohesive and flexible films were formed from galactomannans plasticized with 20-60% (w/w of polymer) glycerol or sorbitol. Galactomannans with lower galactose content (locust bean gum, modified guar gum) produced films with higher elongation at break and tensile strength. The mechanical properties of films were improved statistically significantly by decreasing the degree of polymerization of guar gum with mannanase treatments (4 h) of 2 and 10 nkat/g, whereas 50 nkat/g produced films with low elongation at break and tensile strength. Galactomannans with approximately 6 galactose units per 10 mannose backbone units resulted in films with 2 peaks in loss modulus spectra, whereas films from galactomannans with approximately 2 galactose groups per 10 mannose units behaved as a single phase in dynamic mechanical analysis.

Showing similarity of results given by two methods: a commentary.

There is a frequent need in the environmental sciences to show the similarity of the results given by two analytical methods. This cannot, however, be done within the conventional 'there is a difference' statistical hypothesis setting of, among others, Student's t-test. We demonstrate here a more appropriate approach that originates from drug testing and that can be applied with standard statistical software. It is a challenging approach, as it requires quantification of the similarity limit. If no pre-determined value is given for similarity, a potential data-supported similarity limit can be explored from the data. The approach has numerous other potential application areas, e.g. parallelism of regression slopes, homogeneity of variances and lack of interaction.