Comparison of the growth inhibitory effects of canine IFN-alpha, -beta and -gamma on canine cells infected with Neospora caninum tachyzoites

The growth inhibitory effects of recombinant canine interferon alpha (IFN-alpha), beta (IFN-beta) and gamma (IFN-gamma) were examined on Madin-Darby canine kidney cells infected with Neospora caninum tachyzoites. The parasite growth was inhibited by all IFNs in a dose-dependent manner. IFN-gamma inhibited the parasite growth with greater efficacy than IFN-alpha or IFN-beta. Moreover, the effect of IFNs on N. caninum growth associated with the suppression of the host cell viability. The present study indicates IFN-alpha and -beta, besides IFN-gamma, play a crucial role for N. caninum growth in host cells.     

Quantitative evaluation of flower colour pattern by image analysis and principal component analysis of <Emphasis Type="Italic">Primula sieboldii</Emphasis> E. Morren

In Primula sieboldii E. Morren, many cultivars have been bred with the purpose of obtaining various petal colour patterns. Colour pattern is an important breeding target in this species, and the availability of an objective and quantitative evaluation method is of vital importance for both genetic analysis and variety registration. Our objective was to establish a new quantitative evaluation method of P. sieboldii flower colour patterns in regions of interest (ROIs) by principal component analysis (PCA). We first set a ROI in each petal as a region that represented the petal colour pattern and defined the maximum square on each petal as the ROI. We then converted each ROI image to a 10 × 10 pixel mosaic image and defined a total of 300 variables (the colour values for red, green and blue components of the 100 pixels) per mosaic image. Finally, we summarized the information on the 300 variables by PCA, and redrew the mosaic images to correspond to some typical principal component scores to determine the effect of each principal component on colour pattern. By this method, we detected five different features of petal colour pattern, four of which were revealed to be mainly genetically controlled. Thus, we successfully established a procedure for evaluating petal colour patterns in P. sieboldii cultivars. This new procedure can be used as a basis for an objective and efficient variety registration system.     

Influence of plasticizers on the properties of edible films prepared from fish water-soluble proteins

SUMMARY: The effects of type and concentration of plasticizers on the mechanical properties and water vapor permeability (WVP) of edible films from fish water-soluble proteins (FWSP) were investigated. Among plasticizers investigated in the present study, glycerol and polyethylene glycol (PEG) gave the films flexible structure. As the concentration of glycerol increased, tensile strength (TS) decreased with concomitant increase of elongation at break (EAB) and WVP. In contrast, PEG showed more marked influence on TS than on EAB. The FWSP films containing a glycerol : PEG ratio of 2 : 1 exhibited the maximum EAB value, while the increased ratio of glycerol to PEG reduced the water vapor barrier properties of FWSP films. It was revealed that the mechanical properties as well as WVP of edible films prepared from FWSP can be modified by the combination of glycerol and PEG.     

Spontaneous Cardiac Hypertrophy in a Crl:CD(SD) Rat

Cardiac hypertrophy was observed in a 9-week-old Crl:CD(SD) rat that died unexpectedly. The animal was allocated to the control group of a toxicity study, and no abnormalities in its general conditions, body weight or food intake were observed. Necropsy revealed an increase in heart weight. Gross examination indicated cardiac enlargement with thickening of the right and left ventricular walls. Histopathological examination revealed hypertrophy of the cardiomyocytes in the right and left ventricular walls and the interventricular septum. Electron microscopic examination indicated bizarre nuclei and accumulation of an increased number of various sizes of mitochondria in the perinuclear region of the hypertrophied myocytes. Hypertrophied myocytes connected by intensely folded intercalated disks were also observed. Based on these findings, the animal was diagnosed with cardiac hypertrophy. This is the first case report of cardiac hypertrophy in this strain.     

Malassezia pachydermatis isolated from a South American sea lion (Otaria byronia) with dermatitis

A fungus was isolated from the skin of an Otaria byronia and from the water of the pool in which the animal was kept. It formed creamy colonies with soft texture on Dixon agar and grew well without supplements of long-chain fatty acids. Cells were ovoid to cylindrical in shape, budded from a broad base, and budded and divided at the same location. Thus, the isolate was identified as M. pachydermatis. We compared this very rare isolate from a marine mammal with four strains of M. pachydermatis using the freeze-etching electron-microscopy technique. The cells showed the same characteristic ring-swellings on the protoplasmic membrane on the neck site between the mother and the daughter parts, and the same accumulation of circumvallate bulgings in a small area near the straight sections of spiral grooves as four reference strains. Thus, in terms of morphology and ultrastructure, the isolate could be regarded as a typical M. pachydermatis.     

Expression of porcine interleukin-2 in Escherichia coli

A mature form of porcine interleukin-2 (IL-2) protein without signal peptides was expressed as glutathione S-transferase (GST) fusion proteins in Escherichia coli using pGEX vector. Since most of GST-IL-2 fusion protein was detected in an insoluble fraction on SDS-PAGE analysis, the insoluble fusion protein was solubilized by refolding procedure using urea. The recombinant IL-2 (rIL-2) was purified by a batch method using Glutathione Sepharose 4B and factor Xa digestion and used for preparation of antisera in mice. The antisera reacted with rIL-2 expressed in baculovirus system on immunoblot analysis. In addition, the purified rIL-2 showed a high biological activity on CTLL-2 proliferative response.