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Combined heat and power (CHP) production in buildings is one of the mitigation options available for achieving a considerable decrease in GHG emissions. Micro-CHP (mCHP) fuel cells are capable of cogenerating electricity and heat very efficiently on a decentralised basis. Although they offer clear environmental benefits and have the potential to create a systemic change in energy provision, the diffusion of mCHP fuel cells is rather slow. There are numerous potential drivers for the successful diffusion of fuel cell cogeneration units, but key economic actors are often unaware of them. This paper presents the results of a comprehensive analysis of barriers, drivers and business opportunities surrounding micro-CHP fuel-cell units (up to 5 kWel) in the German building market. Business opportunities have been identified based not only on quantitative data for drivers and barriers, but also on discussions with relevant stakeholders such as housing associations, which are key institutional demand-side actors. These business opportunities include fuel cell contracting as well as the development of a large lighthouse project to demonstrate the climate-neutral, efficient use of fuel cells in the residential building sector. The next step could involve the examination and development of more detailed options and business models. The approach and methods used in the survey may be applied on a larger scale and in other sectors.

Background:There is increasing evidence that lipoprotein-associated phospholipase A2 (LpPLA2) is associated with cardiovascular disease. However, it is still unclear whether LpPLA2 is simply a marker or has a causal role as either a pro- or anti-atherogenic factor. Methods:We analyzed the association of five polymorphisms (−1357G>A, −403T>C, Arg92His, Ile198Thr, Ala379Val) and related haplotypes at the PLA2G7locus with angiographic coronary artery disease (CAD), plasma LpPLA2 activity, and long-term survival in 3234 patients scheduled for coronary angiography. Results:The promoter variant −403C and His92were associated with a decrease and Val379with an increase in plasma LpPLA2 activity. Both coding variants revealed a clear gene-dose effect. Interestingly, the rare Thr198allele, which was not associated with any change in plasma LpPLA2 activity, was more frequent in subjects without CAD (P = 0.009), with an adjusted odds ratio for CAD of 0.69 (95% CI: 0.49–0.96; P = 0.029). None of the analyzed variants showed any robust association with all-cause or cardiovascular mortality. Conclusion:Irrespective of the significant association between some variants with plasma LpPLA2 activity, it is still unclear whether these polymorphisms or haplotypes are associated with the risk and outcome of cardiovascular disease in Caucasians.

The production and study of toxic proteins requires inducible expression systems with low basal level expression and high inducibility. Here, we describe bioprocess applications of the pCytTS temperature-regulatable Sindbis virus replicon-based expression system. We used green fluorescent protein as a marker protein to optimize the selection of stable transfected clones with increased expression levels. Using the optimized protocol, clones were constructed that produced the growth-inhibiting, anti-viral protein interferon β (β-IFN). Selected clones were analyzed for temperature-dependent β-IFN production in adherent and suspension cultures in serum free medium. Specific expression levels were around 1.0 × 10⁵ IU/10⁶ cells/day (0.5 μg/10⁶ cells/day) in suspension cultures and over 1.5 × 10⁶ IU/mL/day (7.5 μg/mL/day) in hollow fiber reactors using adherent cells. Hexahistidine-tagged β-IFN purified from T-flask cultures was highly glycosylated and showed high specific activity. β-IFN mRNA amplified by the viral replicase for 10 days did not show an accumulation of mutations. These data suggest the applicability of the pCytTS-inducible expression system for the production of high-quality glycoproteins in different reactors. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 79: 602–609, 2002.

BACKGROUND/AIMS: Hyperhomocyst(e)inaemia has been identified as a strong risk factor for stroke, myocardial infarction, and deep vein thrombosis. A point mutation of methylene tetrahydrofolate reductase (MTHFR C677T) has been associated with increased plasma homocyst(e)ine levels. To investigate whether hyperhomocyst(e)inaemia and/or MTHFR C677T mutation are associated with non-arteritic ischaemic optic neuropathy (NAION), a case-control study including 59 consecutive patients with NAION and 59 controls matched for age and sex was performed. METHODS: Fasting plasma homocyst(e)ine levels, MTHFR C677T genotypes, and plasma levels of folate and vitamin B-12 were determined. RESULTS: Mean plasma homocyst(e)ine levels were significantly higher in patients than in controls (11.8 (SD 5.7) μmol/l v 9.8 (2.5) μmol/l, p = 0.02). The odds ratio for patients with homocyst(e)ine levels exceeding the 95th percentile of control homocyst(e)ine levels was 5.8 (95% CI 1.5-21.4). Mean plasma folate levels were significantly lower in patients than in controls (4.3 (1.7) ng/ml v 5.5 (1.9) ng/ml, p = 0.001), whereas plasma vitamin B-12 levels did not differ significantly. Prevalence of the MTHFR C677T mutation was not significantly increased in patients with NAION compared with controls. CONCLUSION: These results suggest that hyperhomocyst(e)inaemia, but not MTHFR C677T mutation is associated with NAION. Determination of plasma homocyst(e)ine levels might be of diagnostic value in patients with NAION.

The relationship of three types of personal conflict and clinical symptoms was examined in a group of 139 psychotherapy clients and participants of a psychological training course in the workplace. The participants received the Lauterbach conflict measure and the Symptom Checklist (SCL-90-R). A subgroup of low-conflict and a subgroup of high-conflict participants was formed. Conflict measures and clinical symptoms were highly correlated in the low-conflict group, but not in the high-conflict group. In addition, we showed that the three types of cognitive conflict correlated highly in low-conflict participants but not in the high-conflict subgroup. We concluded that symptoms and conflict account for different dimensions of mental strain in highly conflicted individuals and personal conflict represents a risk factor for developing clinical symptoms. Psychotherapy should not be limited to the symptom dimension but should account for the conflict perspective in an individualized approach.

Ausgehend von der Definition von Membrantragwerken und ihrer Lastabtragung werden die prinzipiellen Möglichkeiten der Stabilisierung von Membranflächen erläutert. Es werden die wichtigsten Membranmaterialien sowie grundsätzliche Entwurfskonzepte vorgestellt. Anhand ausgewählter Beispiele wird die Ausführung von Membrantragwerken erläutert.

We have previously shown that Chinese hamster ovary (CHO) cells capable of growing in medium free of exogenous proteins die by apoptosis during all stages of a batch culture (Zanghi et al., 1999). On the basis of the hypothesis that extracellular death factors might be important in apoptosis under these conditions, we examined the effect of the growth factor inhibitor and antitumor agent suramin on CHO cell growth and apoptosis in serum-free culture. Suramin protected against apoptosis during exponential growth, as indicated by the absence of DNA laddering and an increase in cell viability from roughly 70% to above 95%. Suramin also effectively dispersed cell aggregates so that single-cell suspension culture was possible. However, suramin did not protect against apoptosis during the death phase, in contrast to serum, suggesting that antiapoptotic factors in the serum remain to be discovered. The increased viable cell yield following suramin supplementation resulted in a 40% increase in product yield, based on results with cells expressing recombinant secreted alkaline phosphatase. Polysulfated compounds dextran sulfate and polyvinyl sulfate worked nearly as well as suramin in dispersing cell clumps and increasing viable cell yield, which implies that suramin's high sulfate group density may be responsible for its effects in cell culture. In addition, suramin was beneficial for long-term adaptation of CHO cells to protein-free media suspension culture, and the compound was synergistic with insulin in accelerating this adaptation time.

Damages to inner ear function can be induced by improper application of ear drops. Which of the many substances combined in commercial otological preparations is mainly responsible, still remains a matter of controversy.

We constructed stable Chinese hamster ovary (CHO) cell lines which conditionally and coordinately express the model product gene secreted alkaline phosphatase (SEAP) and one of the cytostatic genes p21, p27, and p53175P, a p53 mutant deficient in apoptotic but not cell-cycle arrest function. The use of dicistronic expression technology allowed the conditional expression of the model product gene and the cytostatic gene in a coordinated fashion from a single expression unit under the control of the tetracycline-responsive promoter PhCMV*-1. Due to the presence of a cytostatic gene in the multicistronic expression unit, the growth behavior of the engineered CHO cell lines could be controlled by the addition or withdrawal of the exogenous agent tetracycline to or from the cell culture medium. Withdrawal of tetracycline resulted in sustained growth arrest of the stable cell lines for a prolonged period. The growth arrest of such cell lines was found to be accompanied by a 10−15-fold increase in their production of SEAP per cell. This controlled proliferation technology allows the design of a novel two-stage production process which consists of a proliferation phase leading to the desired cell density, followed by an extended production phase during which the cells remain growth-arrested and increase cell-specific production of a heterologous protein.