Shiga toxin-producing Escherichia coli in finland from 1990 through 1997: prevalence and characteristics of isolates

During the past 10 years Shiga toxin-producing Escherichia coli (STEC) has emerged as one of the most important causes of food-borne infections in industrialized countries. In Finland, with a population of 5.1 million, however, only four STEC O157:H7 infections were identified from 1990 through 1995; the occurrence of non-O157 STEC infections was unknown. In 1996, we established a national prospective study to determine the prevalence of STEC serotypes in feces of Finns with bloody diarrhea. During this enhanced 1-year study period eight sporadic cases of STEC infection were found; of them, only two were indigenously acquired O157:H7 infections. In 1997, O157 infections increased dramatically, with O157 strains causing 51 of all 61 STEC infections. Altogether 14 non-O157:H7 STEC strains were found in Finland in the 1990s: O26:H11 (four strains), O26:HNM (HNM indicates nonmotile), O2:H29, O91:H21, O91:H40, O101:HNM, O107:H27, O157:HNM, O165:H25, OX3:H21, and Rough:H49. All O157:H7 and O26:H11 isolates produced enterohemolysin, but seven of the other STEC strains did not. Most (n = 63) of the 71 STEC strains isolated carried the stx2 gene only, five carried the stx1 gene only, and three carried both genes. The eaeA gene was detected in all other isolates except five non-O157 strains. There were seven distinct pulsed-field gel electrophoresis (PFGE) genotypes among 57 O157 strains and three distinct PFGE types among four O26:H11 strains. The main PFGE type was found among 65% of all O157 isolates.     

Urgent need for new approach to energy policy: The case of Finland

The process of climate change is already under way and is a serious threat facing the planet. Our response to this threat will irrevocably transform the energy sector and the priorities within it. The trend in emissions over the next decade will largely determine whether the process of climate change can be kept at a moderate level. This literature-based study focuses on Finland as an example case. Oil price fluctuations, economic development and changes in consumer values and attitudes are key forces that will drive change in the energy sector. A greater diversity of energy sources is vital if we are to avoid a catastrophic warming of the climate. The use of renewable energy sources must be increased, and the efficiency of producing, transmitting and distributing energy must be improved. The energy sector must also exploit the potential of nuclear energy, wind, solar and hydro power, afforestation measures, biomass resources, carbon capture and storage (CCS) technology and the nano-bio sector. National policies and measures must be set out in detail and global cooperation enhanced. The presence and impact of factors that impede the work to curb climate change must also be taken into account in energy strategies if these strategies are to be successful.     

Vitamin E and probucol reduce urinary lipophilic aldehydes and renal enlargement in streptozotocin-induced diabetic rats

Diabetes mellitus is characterized by complications affecting several organs, including the kidney. Lipid peroxidation increases in diabetes and has been implicated in the pathogenesis of diabetic complications. In this study, we examined the ability of two antioxidants, vitamin E and probucol, to reduce lipid peroxidation in vivo and renal hypertrophy, an early stage of diabetic nephropathy, in rats. Animals were divided into four groups: non-diabetic, diabetic, diabetic treated with vitamin E, and diabetic treated with probucol. Animals were given antioxidants by intraperitoneal injection after induction of diabetes by streptozotocin injection. After 7 wk, lipid peroxidation in vivo was measured by analyzing urinary excretion of lipophilic aldehydes and related carbonyl compounds (LACC) as 2,4-dinitrophenylhydrazones by high-performance liquid chromatography. A number of urinary lipophilic nonpolar and polar aldehydes and related carbonyl compounds were identified, almost all of which increased in diabetes. Antioxidant treatment resulted in significantly decreased excretion of urinary LACC excretion. Antioxidant treatment of diabetic rats reduced renal hypertrophy. There was a high correlation between kidney weight and urinary LACC. Since LACC are accepted markers of lipid peroxidation, these results indicate that antioxidants can reduce the elevated lipid peroxidation of diabetes and may slow the onset of diabetic nephropathy.     

Separation of α-tocopherol and its oxidation products by high performance liquid chromatography

A very sensitive high performance liquid chromatographic (HPLC) method was developed for the separation of α-tocopherol (α-T) and its five oxidation products: α-tocopheryl quinone (TQ), dimer (D), dihydroxy dimer (DHD), trimer (T) and 9-methoxy-α-tocopherone commonly called α-tocopheroxide (TO). The separation was achieved on a normal-phase silica-based column (Ultrasphere-Si), using a mobile phase of hexane/chloroform/isopropanol (95∶4.5∶0.5, v/v/v) at a flow rate of 0.4 ml/min, and the eluants were monitored simultaneously at their maximum absorptions using a variable-wavelength UV detector. The minmum detection limit is 0.01 μg for α-T, TQ and TO, 0.05 μg for DHD and D, and 0.1 μg for T/injection. This normal-phase method has the combined advantages of being very sensitive, fast and capable of separating all six compounds at the same time.     

Neonatal 6-hydroxydopamine alters the behavior of enriched-impoverished rats in a novel test environment.

The hypothesis that neonatal norepinephrine (NE) depletion lessens the behavioral consequences of differential housing was tested. Male Wistar rats were injected with 6-hydroxydopamine (6-OHDA) or vehicle twice within 24 hr of birth, weaned at 25 days, and reared under either impoverished (IC) or enriched conditions (EC) for 30 days. In 3 experiments, rats were tested in the Morris water maze, the colony-intruder test, and 2 tests of dominance. 6-OHDA treatment reduced cortical and hypothalamic NE concentrations and increased brainstem NE concentrations. EC housing increased cortical dopamine (DA). Behavioral differences caused by postweaning enrichment–isolation were reduced by neonatal NE depletion, primarily in early test trials. The authors conclude that forebrain NE afferents from the locus coeruleus are important for housing-related behavioral changes and responsivity to novel testing environments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Oxidation of polyphenols in unfermented and partly fermented cocoa beans by cocoa polyphenol oxidase and tyrosinase

Unfermented and partly fermented dried cocoa beans have an excessively astringent and bitter flavour owing to their high polyphenol content. Studies on the remaining polyphenol oxidase activity and the oxidation of polyphenols in these beans have been conducted in relation to two factors, ie incubation time (0, 1, 2, 4, 8 and 16 h) and pH of incubation (3.5, 4.5, 5.5 and 6.5). Owing to unsuccessful polyphenol oxidation during incubation of partly fermented beans, incubation–enrichment treatments were carried out by combining incubation time (0, 8, 16, 24 and 32 h) and addition of crude cocoa polyphenol oxidase and purified tyrosinase from mushroom at 88 and 8800 units g^?1 and pH 5.5. Results showed that the remaining polyphenol oxidase activities of unfermented and partly fermented dried beans were 1 and 0.08% with specific activities of 9 and 1% respectively. The polyphenols of unfermented beans were effectively oxidised by incubation at 45 °C and pH 3.5–6.5 without enzyme enrichment; while those of partly fermented beans required enzyme enrichment. Both crude cocoa polyphenol oxidase and tyrosinase could be used for enzyme enrichment, but tyrosinase seemed to be more effective. © 2002 Society of Chemical Industry     

Multi-criteria evaluation of residential energy supply systems

In this paper, we consider the selection of a residential energy supply system as a multi-criteria decision-making problem, which involves both financial and environmental issues. Specifically, we compare micro-CHP (micro-cogeneration) heating with traditional heating systems through an evaluation that accounts for: (i) the decision-makers’ subjective preferences, (ii) uncertainties in the performance of micro-CHP heating systems (which are partly caused by the lack of long-term operational experiences) and (iii) the context-dependency of life-cycle costs and environmental burdens of heating systems. Motivated by these considerations, we employ the PAIRS multi-criteria decision-making methodology that captures incomplete information by way of interval-valued parameters and provides support for sensitivity analyses, too. Our comparative analysis of alternative heating systems suggests that micro-CHP is a reasonable alternative to traditional systems, particularly from the environmental point of view.     

Estimating the environmental burdens of residential energy supply systems through material input and emission factors

This paper introduces a method and application for the assessment of environmental burdens due to the construction and operation of a residential energy supply system. The methodology encompasses energy and environmental impact analyses with sensitivity analysis. Here, natural resource consumption is assessed through material input factors. Global warming and acidification potentials are estimated by way of CO₂− and SO₂− equivalents. A simple optimization scheme is established to capture uncertainties related to preferential treatment between natural resource categories. A computational study on the energy supply of a group of low-energy single-family houses in Finland is presented. Specifically, the potential of micro-cogeneration is evaluated with respect to traditional options based on grid electricity, district heat and natural gas. The energy analysis suggests that the operation of a heating system causes a major part of environmental burdens and that no more than 1000 W on-site generated electrical power per one household would result in minimum thermal losses and thus environmental burdens. On the basis of environmental impact analysis, the use of state-of-the-art micro-cogeneration may decrease the annual use of abiotic resources and water to some extent, but for practical applications, further improvement of system efficiency is still required.