Operational optimization at the Nenäinniemi wastewater treatment plant's tertiary disc filter phosphorus removal installation to reduce chemical consumption.

Instrumentation, automation and control in municipal wastewater treatment can result in large resource, cost and energy savings. Feedforward and feedback control algorithms were implemented together with turbidity and phosphorus analysers to control the chemical dose at the tertiary stage of the Nenäinniemi wastewater treatment plant, consisting of coagulation, flocculation and microsieve filtration. This optimization lowered the coagulant dose by 70% and the polymer dose by 36% compared to manual adjustments of the chemical dosing. Effluent total phosphorus (TP) and total suspended solids (TSS) concentrations were lowered by 20-30%. With the control system in operation, the annual savings in coagulant and polymer were in the range of 100 and 1.4 tons, respectively. Conducting automated CIP on the media at an economical break-even interval of approximately 20 days was also important to further lower energy usage and operational costs.

Toxicological profile of ultrapure 2,2',3,4,4',5,5'-heptachlorbiphenyl (PCB 180) in adult rats.

PCB 180 is a persistent non-dioxin-like polychlorinated biphenyl (NDL-PCB) abundantly present in food and the environment. Risk characterization of NDL-PCBs is confounded by the presence of highly potent dioxin-like impurities. We used ultrapure PCB 180 to characterize its toxicity profile in a 28-day repeat dose toxicity study in young adult rats extended to cover endocrine and behavioral effects. Using a loading dose/maintenance dose regimen, groups of 5 males and 5 females were given total doses of 0, 3, 10, 30, 100, 300, 1000 or 1700 mg PCB 180/kg body weight by gavage. Dose-responses were analyzed using benchmark dose modeling based on dose and adipose tissue PCB concentrations. Body weight gain was retarded at 1700 mg/kg during loading dosing, but recovered thereafter. The most sensitive endpoint of toxicity that was used for risk characterization was altered open field behavior in females; i.e. increased activity and distance moved in the inner zone of an open field suggesting altered emotional responses to unfamiliar environment and impaired behavioral inhibition. Other dose-dependent changes included decreased serum thyroid hormones with associated histopathological changes, altered tissue retinoid levels, decreased hematocrit and hemoglobin, decreased follicle stimulating hormone and luteinizing hormone levels in males and increased expression of DNA damage markers in liver of females. Dose-dependent hypertrophy of zona fasciculata cells was observed in adrenals suggesting activation of cortex. There were gender differences in sensitivity and toxicity profiles were partly different in males and females. PCB 180 adipose tissue concentrations were clearly above the general human population levels, but close to the levels in highly exposed populations. The results demonstrate a distinct toxicological profile of PCB 180 with lack of dioxin-like properties required for assignment of WHO toxic equivalency factor. However, PCB 180 shares several toxicological targets with dioxin-like compounds emphasizing the potential for interactions.

Combination of LC-MS/MS aldosterone and automated direct renin in screening for primary aldosteronism.

BACKGROUND: Aldosterone to renin ratio (ARR) is used in screening for primary aldosteronism (PA). However, there are only few studies on the influence of assay methods on ARR and its cut-off limits. METHODS: Plasma direct renin immunoreactivity by chemiluminescence immunoassay (DR) was compared to renin activity assay (PRA), and a specific liquid chromatography-mass spectrometric method (LC-MS/MS) to radioimmunoassay (RIA) for plasma aldosterone. There were 75 samples for renin assays, and 42 samples of 39 patients for both renin and aldosterone assays. PA screening was considered positive if ARR by the aldosterone RIA:PRA was ≥800pmol/L:µg/L/h or by LC-MS/MS:DR≥44pmol/L:ng/L. RESULTS: The correlation between the DR and PRA methods (n=75, r(2)=0.845) and between LC-MS/MS and RIA (n=42, r(2)=0.973) was high in general, but low between the renin methods (n=49, r(2)=0.435) at low PRA values. When ARR was used in screening for PA, there were three divergent cases (positive only by alternative methods), but when applied in combination with criteria for elevated aldosterone, the methods showed good agreement, resulting in eight positive and 31 negative screening results. CONCLUSIONS: The automated DR assay combined with LC-MS/MS method for aldosterone provides a rapid, reliable, and specific method for screening of PA.

High-throughput analysis of testosterone in serum samples by on-line solid phase extraction liquid chromatography-tandem mass spectrometry.

BACKGROUND: Liquid chromatography tandem-mass spectrometer (LC-MS/MS) techniques are more and more common in the measurement of testosterone concentrations in biological samples. However, LC-MS/MS methods are more laborious than streamlined automated immunochemistry methods because of the need for tedious pre-purification of the sample before the mass spectrometric analysis. We therefore developed a robust and rapid sample clean-up method to improve the throughput of the whole LC-MS/MS analysis procedure by applying an automated on-line solid-phase extraction (SPE) technique instead of the still widely used conventional liquid-liquid extraction. METHODS: Testosterone was purified by the on-line SPE-column-switching technique after rapid precipitation of serum samples by zinc sulphate/internal standard solution before LC-MS/MS analysis. The results were compared with those of our previous routine LC-MS/MS method using liquid-liquid extraction with tert-butyl methyl ether for the pre-purification of the samples. RESULTS: The tested on-line SPE-LC-MS/MS method reached the specifications of the previous method with liquid-liquid extraction. The precision of the new method was notably better, especially in the lower concentration range, than with the former method; the total variation was below 10% in the whole quantitation range of 0.25-35 nmol/L. The new method liberates more than 50% of hands-on time of laboratory technicians as well as expensive instrument time for other applications compared with the older method. CONCLUSIONS: The on-line SPE-pre-purification technique tested in long-term use offers a rapid and reliable technique in the LC-MS/MS analysis of serum testosterone and is a valuable tool in the improvement of efficiency in the laborious steroid analytics.

Difference between total and intact assays for N-terminal propeptide of type I procollagen reflects degradation of pN-collagen rather than denaturation of intact propeptide.

BACKGROUND: The concentration of N-terminal propeptide of type I procollagen (PINP) in the serum reflects the rate of type I collagen formation. Intact PINP assay measures the trimeric propeptide while total P1NP assay measures both trimeric and monomeric forms. In this study we compared these two assays emphasizing the possible differences. METHODS: Intact and total PINP were measured from serum in healthy Finnish blood donors (n = 34) and in the patients with chronic renal failure before and after haemodialysis (n = 39). In addition, the serum of a normal man, pooled hospital serum samples and the serum of a patient with haemodialysis treatment were fractioned by gel filtration and trimeric and monomeric forms were located. Fractions were lyophilized and intact and total PINP were measured in each fraction. Samples from bedridden geriatric patients (n = 173) were also measured using intact and total PINP assays and a degradation marker of type I collagen (ICTP). RESULTS: The correlation between intact and total PINP in controls was 0.89 and their PINP concentrations were similar. In haemodialysis or bedridden geriatric patients, the PINP methods gave significantly different results. In gel filtration studies, intact PINP hardly measured monomeric form even if its concentration was disproportionately increased in haemodialysis patients. In bedridden geriatric patients, the difference of total and intact PINP correlated significantly to degradation marker ICTP. CONCLUSIONS: Difference between total and intact assays for PINP seem to reflect degradation of pN-collagen rather than denaturation of intact propeptide.

Serum dehydroepiandrosterone sulfate concentration as an indicator of adrenocortical suppression during inhaled steroid therapy in adult asthmatic patients.

OBJECTIVE: Supraphysiological doses of exogenous glucocorticosteroids cause adrenocortical suppression. Dehydroepiandrosterone sulfate (DHEA-S) is the most abundant adrenal androgen and estrogen precursor. We studied to what extent inhaled glucocorticosteroid therapy for asthma decreases serum DHEA-S concentrations. DESIGN AND METHODS: We measured serum DHEA-S and cortisol concentrations in 101 adult patients with newly detected mild asthma before and after 2 and 12 weeks of treatment with inhaled glucocorticosteroids. The patients were randomized to receive budesonide 200 microg/day (low dose group, n=50) or 800 microg/day (high dose group, n=51) in two parallel groups double-blindly. RESULTS: In the low dose group, serum DHEA-S concentrations decreased from the baseline by a mean of 8 % (95 % confidence interval (CI), 3-13 %, P<0.01) after 2 weeks of therapy, and by 2 % (95 % CI, 9 % decrease to 5 % increase, NS) after 12 weeks. In the high dose group, the respective decreases were 16 % (95 % CI, 10-21 %, P<0.001) and 18 % (95 % CI, 12-24 %, P<0.001). The difference between the treatment groups was significant at both 2 and 12 weeks. During the 12 week treatment period the baseline concentrations of serum cortisol did not decrease in the low dose group, while in the high dose group the decrease was significant at 12 weeks (P<0.01), but not at 2 weeks. The forced expiratory volume in 1 s improved equally well in both groups. CONCLUSIONS: Inhaled budesonide decreased serum DHEA-S concentrations, which may indicate adrenocortical suppression. Reduced adrenal production of androgen and estrogen precursors may increase the risk of osteoporosis especially in postmenopausal women.

Structural differences between rye and wheat breads but not total fiber content may explain the lower postprandial insulin response to rye bread.

BACKGROUND: Rye bread has a beneficial effect on the postprandial insulin response in healthy subjects. The role of rye fiber in insulin and glucose metabolism is not known. OBJECTIVE: The aim of the study was to determine the effect of the content of rye fiber in rye breads on postprandial insulin and glucose responses. DESIGN: Nineteen healthy postmenopausal women aged 61 +/- 1 y, with a body mass index (in kg/m(2)) of 26.0 +/- 0.6, and with normal glucose tolerance participated in the study. The test products were refined wheat bread (control), endosperm rye bread, traditional rye bread, and high-fiber rye bread; each bread provided 50 g available carbohydrate and was served with breakfast. Plasma glucose, insulin, glucose-dependent insulinotropic polypeptide, glucagon-like peptide 1, and serum C-peptide were measured in fasting and 8 postprandial blood samples. In vitro starch hydrolysis and the microscopic structure of the breads were also determined. RESULTS: Postprandial insulin, glucose-dependent insulinotropic polypeptide, and C-peptide responses to the rye breads were significantly lower than the response to the control; no significant differences in insulin and C-peptide responses to the rye breads were found. Glucose and glucagon-like peptide 1 responses to the rye breads were not significantly different from those to the control, except at 150 and 180 min. In vitro starch hydrolysis was slower in all rye breads than in the control, and the structure of continuous matrix and starch granules differed between the rye and control breads. CONCLUSION: Total fiber content does not explain the lower postprandial insulin response to rye bread than to wheat bread, but structural differences between rye and wheat breads might.

Allergen-specific immunoglobulin E antibodies in wheezing infants: the risk for asthma in later childhood.

OBJECTIVE: To evaluate whether the measurement of specific immunoglobulin E (IgE) antibodies to food and/or inhalant allergens in infants who are hospitalized for wheezing can be used to predict later asthma. METHODS: Eighty-two children who were hospitalized for wheezing at <2 years of age were followed prospectively until early school age. The baseline data and the characteristics of infancy had been collected at enrollment. At school age, the children were evaluated for asthma and allergic manifestations, including skin prick tests to common inhalant allergens. Frozen serum samples obtained during the index episode of wheezing were available for 80 children for determination of food and inhalant allergen-specific serum IgE antibodies by fluoroenzyme-immunometric assay, UniCAP, applying the Phadiatop Combi allergen panel. RESULTS: Asthma was present in 32 (40%) children at school age. Food-specific IgE antibodies of >or=0.35 kU/L were found in 37 (46%) wheezing infants, but only specific IgE to wheat and to egg white at the level of >or=0.35 kU/L were significantly associated with later asthma. In regard to specific IgE to the mixture of food allergens, the cutoff level of >or=0.70 proved to be significant. Inhalant allergen-specific IgE of >or=0.35 kU/L was found only in 14 cases (18%), but when present, it was significantly predictive of asthma. Elevated levels of specific IgE antibodies to food or inhalant allergens were significantly associated with allergic rhinitis and skin-test reactivity at school age. CONCLUSIONS: When present in wheezing infants, specific IgE of >or=0.35 kU/L to wheat, egg white, or inhalant allergens are predictive of later childhood asthma. Consequently, detection of those specific IgE antibodies in wheezing infants may facilitate the early diagnosis of asthma, especially in cases with no clinically evident atopic manifestations.