Polypores new to Japan 1. Species ofPolyporus,with a note onP. hartmanni

Polyporus admirabilis, P. dictyopus, P. guianensis, P. pseudobetulinus, P. tubaeformis andP. udus are reported for Japan for the first time.Polyporus tubaeformis had been confused withP. melanopus, but the Japanese collections were conspecific with Norwegian isolates ofP. tubaeformis. A key to allPolyporus species in Japan is provided.Polyporus hartmanni is reported for the first time outside the Australian continent. As the species has a bipolar heterothallism and produces brown rot, its taxonomic relationship withPolyporus s. str. is discussed.The Japanese Science and Technology Agency (STA) is thanked by the authors for financial support.     

Proteolytic cleavage of recombinant two-chain factor VIII during cell culture production is mediated by protease(s) from lysed cells. The use of pulse labelling directly in production medium

During the production by mammalian cells of recombinant factor VIII from which the B domain was deleted (rFVIII), proteolytic cleavages in the C-terminal part of the heavy chain were observed (Kjalke et al., 1995). By radioactive pulse labelling it was investigated whether the cleavages took place inside the cells during protein synthesis or after release in the medium. The rFVIII-producing CHO (Chinese hamster ovary) cells were cultured in the presence of ³⁵S-methionine and then the cell lysate and the conditioned media were immunoprecipitated and analyzed by electrophoresis. By pulse labelling and chasing for various time periods, it was shown that the cleavages only took place after secretion of the protein from the cells. Adding cell lysate to uncleaved rFVIII caused cleavage of the heavy chain, as seen by loss of binding to a monoclonal antibody specific for intact rFVIII, indicating that the cleavage was performed by proteinase(s) released from the lysed cells. By incubating intact rFVIII with the multicatalytic proteinase (proteasome) present in cytoplasm and nucleus of eukaryotic cells, loss of binding to the monoclonal antibody was observed. This indicates that the multicatalytic proteinase, released from lysed rFVIII producing cells, could be responsible for the cleavage of rFVIII. Among several protease inhibitors tested, only bacitracin was found to diminish the extent of cleavage. Phosphatidylserine also protected rFVIII against cleavage, probably by binding to rFVIII. This revised version was published online in July 2006 with corrections to the Cover Date.     

Defective regulation of the cytosolic Ca2+ activity in parathyroid cells from patients with hyperparathyroidism

The parathyroid hormone (PTH) release and cytosolic Ca²⁺ activity were determined in normal bovine parathyroid cells and parathyroid cells obtained from patients with hyperparathyroidism (HPT). There was a sigmoid relation between the cytosolic Ca²⁺ activity and the extracellular calcium concentration between 0.5 and 6.0 mmol/l. The PTH release was inhibited in parallel with the rise in the cytosolic Ca²⁺ activity. Both the hormone release and the cytosolic Ca²⁺ activity were lower in cells from human adenomas and hyperplastic glands~ and in comparison with the bovine preparations these ceils had higher set points for the cytosolic Ca²⁺ activity and PTH release. There was a close correlation between the individual set points for the cytosolic Ca²⁺ activity and PTH release in a material containing both normal and pathological cells. The results indicate that the abnormal PTH release characteristic of HPT is due to a defective regulation of the cytosolic Ca²⁺ activity.     

Pronounced inhibition of noradrenaline uptake by 10-hydroxymetabolites of nortriptyline

The potency of the tricyclic antidepressant nortriptyline (NT) relative to that of its major metabolite (E-10-hydroxynortriptyline; E-10-OH-NT) to inhibit the uptake of noradrenaline in rat brain slices incubated in human plasma was 1.75 ± S.D. 0.30. The E- and Z-isomers of 10-OH-NT were equipotent. Hydroxy-metabolites of NT or amitriptyline did not inhibited the neuronal uptake of serotonin.During treatment of 87 patients with NT or amitriptyline the mean ratio between the plasma levels of unconjugated 10-OH-NT and NT was 1.40 ± S.D. 0.86 with a range of 0.32 – 5.0. This ratio increased with age. There was a significant correlation between the plasma levels of the two compounds (r = 0.63; p < 0.001). In three patients treated with NT, the CSF levels of the parent drug and unconjugated 10-OH-NT were similar and about 5 % of the plasma levels.These results indicate that during treatment with NT (or amitriptyline) 10-OH-NT contributes to the effect of these drugs on central noradrenergic neurons. This seems to be of special significance in the elderly.     

Biology of the minnow Phoxinus phoxinus and its interactions with brown trout Salmo trutta in Øvre Heimdalsvatn, Norway

Minnows have recently been introduced into the mountain lakes of southern Norway. In Øvre Heimdalsvatn, an intensively studied lake, the minnow population has increased rapidly during the last decade. Studies were performed on feeding habits, habitat preferences, age, growth, energy content, densities, parasites, predation and spawning activities. Several aspects were found to be different from other studies, e.g. higher age of sexual maturation, lower growth rate, no feeding on plants, and low infection of parasites. The interaction with the only other fish, the brown trout, is discussed in relation to the minnow population. In 1978 the minnows constituted little more than 10% of production and food consumption of the trout population, and only limited food competition and predation was documented. Increasing competition is likely with a greater minnow population.     

Engineering of lactose metabolism inE. coli by introducing β-galactosidase/galactokinase fusion enzymes

Summary A series of plasmids encoding -galactosidase/galactokinase fusion proteins with connecting linkers of different lengths and properties separating the enzyme moieties were made.E. coli cells harbouring the genes for these bifunctional enzymes were grown on minimal media with lactose as carbon source in order to asses possible metabolic effects. Differences in growth rates were observed when the cells contained a scavenger enzyme, galactose dehydrogenase, competing with galactokinase for the galactose formed by -galactosidase.E. coli cells coding for fusion proteins with long linkers then reflected markedly slower growth rates.     

Ada software for cytometry.

Ada is a new general-purpose language that embodies the concepts of software engineering. Although it was initially developed for military purposes, it is suitable for developing software for cytometry and other health-related applications. A pilot study has demonstrated the feasibility of employing Ada for cytometry applications. Three packages were created. The first subtracts a control three-dimensional population from multiple individual experimental populations and presents the results in spread sheet form. A second package has the capability of finding aggregates of cells. The results of this package are visualized employing a commercially available program for three-dimensional presentation of the data that permits rotation in real time. A third package consists primarily of interface drivers for two commercially available personal computer boards, an ADC and a stepper motor controller. The major problems with the coding were due to incomplete implementation of the language. This pilot study, together with others, indicates that it would be both cost effective and beneficial to implement cytometry and other medical devices in Ada.     

Year-class strength regulation in plaice (Pleuronectes platessa L.) on the Swedish west coast

Year-class strength of plaice (Pleuronectes platessa) has been studied over periods of 10 and 35 years, respectively, in two shallow sandy areas on the Swedish west coast. In one area, Gullmar Bay (N 58 ° 19 – W 11 ° 33), 0-group plaice were sampled quantitatively with a drop trap at 0–0.7 m depth and densities between 0.2 and 3.8 ind./m² were recorded in early summer. In the other area, Laholm Bay (N 56 ° 30 – W 12 ° 55), 0-group plaice were sampled semi-quantitatively in August with young-fish trawl at 1.5 m depths. Densities between 0.001 and 0.28 ind./m² were assessed.The effects of temperature and wind (in the winter and early spring) and predation (in early summer), on the recruitment of 0-group plaice were investigated. In Gullmar Bay high recruitment occurred after severe winters and in years when on-shore winds dominated during spring. No such correlations were found in Laholm Bay. In Gullmar Bay a significant inverse relationship was found between the density of O-group plaice in early summer and the biomass of brown shrimp (Crangon crangon) and the shore crab (Carcinus maenas), the main predators in the nursery area.The importance of physical and biological factors regulating recruitment in plaice are discussed.