GM1 gangliosidosis in a Japanese domestic cat: a new variant identified in Hokkaido,Japan

A male Japanese domestic cat with retarded growth in Hokkaido, Japan, showed progressive motor dysfunction, such as ataxia starting at 3 months of age and tremors, visual disorder and seizure after 4 months of age. Finally, the cat died of neurological deterioration at 9 months of age. Approximately half of the peripheral blood lymphocytes had multiple abnormal vacuoles. Magnetic resonance imaging showed bisymmetrical hyperintensity in the white matter of the parietal and occipital lobes in the forebrain on T2-weighted and fluid-attenuated inversion recovery images, and mild encephalatrophy of the olfactory bulbs and temporal lobes. The activity of lysosomal acid β-galactosidase in leukocytes was negligible, resulting in the biochemical diagnosis of GM1 gangliosidosis. Histologically, swollen neurons characterized by accumulation of pale, slightly granular cytoplasmic materials were observed throughout the central nervous system. Dysmyelination or demyelination and gemistocytic astrocytosis were observed in the white matter. Ultrastructually, membranous cytoplasmic bodies were detected in the lysosomes of neurons. However, genetic analysis did not identify the c.1448G>C mutation, which is the single known mutation of feline GM1 gangliosidosis, suggesting that the cat was affected with a new variant of the feline disease.     

Real-time PCR genotyping assay for feline erythrocyte pyruvate kinase deficiency and mutant allele frequency in purebred cats in Japan

Erythrocyte pyruvate kinase (PK) deficiency is an inherited glycolytic erythroenzymopathy caused by mutations of the PKLR gene. A causative mutation of the feline PKLR gene was originally identified in Abyssinian and Somali cats in the U.S.A. In the present study, a TaqMan probe-based real-time PCR genotyping assay was developed and evaluated for rapid genotyping and large-scale screening for this mutation. Furthermore, a genotyping survey was carried out in a population of four popular purebred cats in Japan to determine the current mutant allele frequency. The assay clearly displayed all genotypes of feline PK deficiency, indicating its suitability for large-scale survey as well as diagnosis. The survey demonstrated that the mutant allele frequency in Abyssinian and Somali cats was high enough to warrant measures to control and prevent the disease. The mutant allele frequency was relatively low in Bengal and American Shorthair cats; however, the testing should still be carried out to prevent the spread of the disease. In addition, PK deficiency should always be considered in the differential diagnosis of anemia in purebred cats in Japan as well as worldwide.     

Effect of dietary supplementation with taurine, β-alanine andGABA on the growth of juvenile and fingerling Japanese flounder Paralichthysolivaceus

ABSTRACT:   Three diets supplemented with taurine, β-alanine andGABA and a control diet were fed to juvenile and fingerling Japaneseflounder to investigate the effects of the diets on growth and metabolicchanges of free amino acids in whole body and tissues. In experimentI, three diets supplemented with 1% each of taurine, β-alanineand GABA and a control diet were fed to juvenile Japanese flounderwith an initial mean body weight of 0.4 g for 4 weeks at20°C. In experiment II, the taurine-supplemented diet anda control diet were fed to fingerling Japanese flounder with an initialmean body weight of 15 g for 4 weeks at 20°C.Only supplementation of taurine in the diet of juvenile flounderimproved their growth performance in experiment I, but fingerlinggrowth performance of experiment II was not significantly relatedto taurine supplementation in the experimental diet. These resultssuggest that there is a greater requirement for taurine for thegrowth of juvenile Japanese flounder than fingerling Japanese flounder.     

Distribution and stem growth patterns of mangrove species along the Nakara River in Iriomote Island, Southwestern Japan

We examined variations in stand structure and tree growth of a mangrove forest along two gradients: from the river mouth to upper stream and from the riverside to inland, along the Nakara River, Iriomote Island, Japan. Bruguiera gymnorrhiza (L.) Lamk. occurred throughout the intertidal area, though Rhizophora stylosa Griff. and Kandelia candel (L) Druce did not occur upstream. Basal area and maximum tree height of B. gymnorrhiza decreased downstream. The growth rate in stem diameter of B. gymnorrhiza decreased downstream in relation with the soil salinity. The basal area and the maximum tree height of B. gymnorrhiza increased with the distance from the riverside. R. stylosa increased in stem diameter and growth rate toward the riverside.     

The profile of urinary lipid metabolites in healthy dogs

Polyunsaturated fatty acids, including arachidonic acid (AA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA), are converted to hundreds of lipid mediators by cyclooxygenases (COX), lipoxygenases (LOX), and cytochrome P450 (CYP), or through non-enzymatic processes, and they reflect inflammatory states of the body. We comprehensively analyzed lipid metabolites in dog urine using a liquid chromatograph-mass spectrometry (LC-MS/MS) to describe their metabolic characteristics. We detected 31 AA-derived metabolites, four EPA-derived metabolites, and a DHA-derived metabolite in all urine samples. Among AA-derived metabolites, 15, 5, 3, and 8 were generated by COX, LOX, CYP, and non-enzymatic oxidation respectively. This study will be the first step to use profiles of urinary lipid metabolites for better understanding and diagnosis of canine diseases.