Neuropeptide Y: a novel link between the neuroendocrine system and cholesterol metabolism

High serum total and low-density lipoprotein (LDL) cholesterol levels constitute the main risk factor for atherosclerotic vascular diseases. Both genetic and environmental factors are involved in the regulation of serum cholesterol levels. Neuropeptide Y (NPY), which is widely expressed in both the central and peripheral nervous systems, is known to regulate food intake and energy balance but its role in cholesterol metabolism has remained almost untouched in former literature. A newly discovered association between a leucine(7)-to-proline(7) polymorphism (Pro(7)) in the signal peptide of NPY and a high cholesterol level may provide new ideas for the genetic regulation of cholesterol metabolism. The presence of the Pro(7) in NPY results in serum total cholesterol levels 0.6-1.4 mmol/L higher compared with subjects without this gene variant. The Pro(7) in NPY was detected in 14% of Finns but only in 6% of Dutchmen, and its impact on serum cholesterol concentration seems to be stronger in obese than in normal-weight subjects. At least among Finns, the Pro(7) in NPY is one of the strongest genetic factors identified thus far affecting serum cholesterol levels.     

A workbench for distributed production management systems

An end-user oriented workbench approach in the design of distributed production management systems (DPMS) is presented. We shall also deal with models and design of DPMS. Changes anticipated in design processes, roles and professionality required are discussed. In fact, complete structural rearrangements in the design of production management systems (PMS) are expected towards the end of this decade. The ideas presented are based on an on-going research project at Helsinki University of Technology (the so-called HUTDPMS project).     

Shape recognition by a scale-invariant model

In this article, we considered the recognition of unknown shapes by maximum likelihood methods. The contour of a shape is represented by its centroidal profile, and it is fitted by a circular autoregressive model. Two different shape recognition problems are considered: the decision on the similarity of two unknown shapes, and the classification of an unknown shape as one of many known shapes. Maximum likelihood decision rules for these two cases are derived. The decision rules are invariant to translation, rotation, and size change after normalizing the estimates. The developed algorithms are applied to classify eight classes of machine parts and eight classes of aircraft shapes. For each class, 60 to 80 samples are generated by rotating and dilating the original shape. In the experiment, more than 98% of machine parts are classified correctly, and more than 97% of aircraft shapes are correctly classified. This result is better than previous model-based approaches. Partially supported by the National Science Foundation under the grant IRI-8809391.     

Structural features of a polypeptide carrier promoting secretion of a β-lactamase fusion protein in yeast

Escherichia coli β-lactamase was secreted into the culture medium of Saccharomyces cerevisiae in biologically active form, when fused to the C-terminus of the hsp150δ-carrier. The hsp150δ-carrier is an N-terminal fragment of the yeast hsp150 protein, having a signal peptide and consisting mostly of a 19 amino acid peptide repeated 11 times in tandem. Here we expressed the hsp150δ-carrier fragment alone in S. cerevisiae. Apparently due to a positional effect of the gene insertion, large amounts of the hsp150δ-carrier were synthesized. About half of the de novo synthesized carrier molecules were secreted into the culture medium, the rest remaining mostly in the pre-Golgi compartment. The extensively O-glycosylated carrier fragment was purified from the culture medium under non-denaturing conditions. Circular dichroism spectroscopy showed that it had no regular secondary structure. Nuclear magnetic resonance spectroscopy showed that a non-glycosylated synthetic peptide, the consensus sequence of the repetitive 19 amino acid peptide, also lacked secondary structure. The unstructured carrier polypeptide may facilitate proper folding and secretion of heterologous proteins attached to it.     

The epidemic cycle of Chlamydia pneumoniae infection in eastern Finland, 1972-1987

The epidemic cycle of Chlamydia pneumoniae infection was examined in two areas in eastern Finland over a period of 15 years, 1972-87. The C. pneumoniae IgG antibody prevalence was determined with 5-year intervals in a random sample of the population aged 25-59 years. The total number of sera studied using immunofluorescence was 2387. In 1972 the antibody prevalence was 57% and it increased to 66% in 1977. Over the next 5 years the prevalence decreased to 44% in 1982, but by 1987 it had again increased to 59%. The temporal variation in prevalence was statistically significant (P < 0.001) and similar for both genders. Throughout the observation period the overall prevalence was 7-11% higher in men than in women (P < 0.01). The antibody prevalence increased with age, being the highest among the oldest study subjects of both genders. The periods of high and low prevalence alternated in an epidemic cycle (P < 0.001) of about 10 years.     

HLA antigens in psoriasis. A family study

HLA antigens were determined in 14 Finnish families with psoriatic members. The pedigrees of all families are presented. The results showed a clear association between HLA B13 and inheritable psoriasis, for all the 14 HLA analysed psoriatic patients in four families had B13. In one family all five psoriatic patients had the haplotype HLA-A10, Bw17; in two other families the association between Bw17 and psoriasis was less obvious. In three families six of the eight children with the haplotype A1, Bw37 had psoriasis. In all these families one parent had psoriasis or psoriatic relatives and the other parent contributed A1, Bw37. It is suggested that Bw37, in association with other genetic factors, indicates a high risk of developing psoriasis. In one family both the father with psoriatic arthritis and the son with post-urethritic Reiter's disease had A2, B27. This haplotype was also possibly associated with psoriatic arthritis in two families.     

Heat treatment studies of a TLCP fiber

This work deals with the heat treatment of fibers and nonoriented specimens made of the thermotropic liquid crystalline polymer Vectra A900 in the light of tensile properties and DSC measurements. In calorimetric measurements, there seem to be some differences in the effects of the treatment between macroscopically isotropic (nonoriented) and highly oriented fiber specimens. Nonisothermal treatments also produce some effects on the tensile properties, which may be attributable to the thermal history of samples. Under the conditions of this study, a multistep treatment, ending at a final stage where the temperature was higher than the original melting point of the polymer, did not cause any acceleration in the rate at which tensile properties increase. © 1993 John Wiley & Sons, Inc.     

Improving integrity of on-line grammage measurement with traceable basic calibration

The automatic control of grammage (basis weight) in paper and board production is based upon on-line grammage measurement. Furthermore, the automatic control of other quality variables such as moisture, ash content and coat weight, may rely on the grammage measurement. The integrity of Kr-85 based on-line grammage measurement systems was studied, by performing basic calibrations with traceably calibrated plastic reference standards. The calibrations were performed according to the EN ISO/IEC 17025 standard, which is a requirement for calibration laboratories. The observed relative measurement errors were 3.3% in the first time calibrations at the 95% confidence level. With the traceable basic calibration method, however, these errors can be reduced to under 0.5%, thus improving the integrity of on-line grammage measurements. Also a standardised algorithm, based on the experience from the performed calibrations, is proposed to ease the adjustment of the different grammage measurement systems. The calibration technique can basically be applied to all β-radiation based grammage measurements.     

The effects of ventilation systems and building fabric on the stability of indoor temperature and humidity in Finnish detached houses

Interest in finding out passive ways to keep the variation in the indoor climate within the comfort zone is gaining in popularity. One possible solution is the use of the moisture-buffering property of materials. In this study, the effects of the ventilation system and moisture-buffering properties of the building fabric on the stability of the indoor temperature and humidity are analysed by means of long-term field measurements. Indoor climate measurements were carried out in 170 detached houses (248 rooms). Temperature and relative humidity were measured continuously in bedrooms and living rooms at one-hour intervals over a one-year period. In general, it may be concluded that in this study, the ventilation had a greater effect on the indoor climate than the properties of the building fabric. The dampening effect of hygroscopic materials was remarkably less in the field measurements than it was in simulations in different studies. This indicates that completely non-hygroscopic and fully hygroscopic houses do not exist in reality. The hygroscopic mass of furniture, textiles, etc. is probably a factor that plays a significant role in indoor humidity, as do real air change rates, including window airing. Simulation tools need to be modified in order to be able also to handle furniture, textiles, and books, etc.