A comparative pathological study on granulomatous meningoencephalomyelitis and central malignant histiocytosis in dogs

Histiocytic proliferative disorders in canine central nervous system (CNS) including granulomatous meningoencephalomyelitis (GME) and malignant histiocytosis were compared pathologically. Lesions of GME mainly existed in the white matter of the cerebrum, brainstem and cerebellum and consisted of characteristic perivascular cuffing, parenchymal granuloma and leptomeningeal infiltrates of mononuclear cells. In malignant histiocytosis, there were two histological patterns, diffuse proliferation of neoplastic histiocytes through the leptomeninges and neoplastic nodule formation in the parenchyma. Neoplastic histiocytes exhibited mild to severe cellular atypia and high ability of invasion into the brain parenchyma. Mitotic and phagocytic figures were also observed. Several histiocytic markers, including lysozyme, alpha1-antitrypsin and lectin RCA-1, revealed histiocytic origin of both inflammatory and neoplastic cells, however, those were not determinative for the discrimination between GME and malignant histiocytosis. CD3- and PCNA-positive cells existed in the lesions of both diseases. The number of CD3-positive cells in GME tended to be greater than in malignant histiocytosis, while the difference was not statistically significant.     

Peroxisome proliferator-activated receptor-γ coactivator 1 α (PGC-1 α) expression and the formation of slow-twitch muscle fibers in porcine and bovine skeletal muscles

The peroxisome proliferator‐activated receptor‐γ coactivator‐1 α (PGC‐1 α) induces mitochondria biogenesis in skeletal muscles. To determine the relationships between PGC‐1 α and the muscle fiber types, the expression levels of PGC‐1 α were analyzed in porcine and bovine skeletal muscles. As a first step, the nucleotide sequences of the porcine and bovine PGC‐1 α were determined. The porcine and bovine PGC‐1 α cDNA encoded 796 amino acid sequences and showed 95.1% identity between the two species. The expression levels of the PGC‐1 α mRNA were analyzed in the same 10 skeletal muscles from four pigs and three cattle. The contents of porcine and bovine PGC‐1 α were higher in the tongue, masseter and diaphragm, and lower in the Biceps femoris, semimembranosus, Longissimus thoracis and semitendinosus muscles. The contents of myosin heavy chain slow‐type protein (MyHC‐slow) were also determined in the same muscles by ELISA. The analysis of MyHC‐slow showed results similar to those for the PGC‐1 α contents in all of the muscles except for the tongue. The content of MyHC‐slow in the tongue was the lowest among the porcine muscles, and moderate among the bovine muscles. The results suggest that PGC‐1 α relates to the development of oxidative muscle fibers, but is not the principal factor in determining type I fiber content.     

Correlation of phytoplasma concentration in Hydrangea macrophylla with green-flowering stability

The interaction between phytoplasma concentration and green-flowering stability was studied in hydrangea cultivars. Three green and 18 nongreen cultivars were subjected to polymerase chain reaction (PCR) analysis to determine Japanese hydrangea phyllody (JHP) phytoplasma infection. The results showed that JHP-phytoplasma was detected only in ‘Midori’ plants, which have green sepals. ‘Midori’ plants were propagated, and from 29 rooted cutting plants, they were grouped into three types on the basis of sepal color, that is, green (75.9%), blue-green (13.8%) and blue (10.3%) sepals. To clarify the variability in the sepal color of ‘Midori’ plants, JHP-phytoplasma concentration in the sepals and leaves of green-, blue-green- and blue-flowering plants was determined by PCR analysis. The semiquantitative PCR comparisons of 370 bp DNA fragments showed that the JHP-phytoplasma concentrations in green sepals were 16 times higher than that in blue-green sepals. JHP-phytoplasma could not be identified by PCR analysis in blue sepals and leaves. These results showed that JHP-phytoplasma concentration correlated with green sepal stability in ‘Midori’ plants. A histological observation of sepals showed that epidermal cells of blue and blue-green sepals had a dome shape. Otherwise, green sepals were leaflike with flat epidermal cells, and palisade parenchyma cells with numerous chloroplasts.     

Mortality of the short-neck clam <Emphasis Type="Italic">Ruditapes philippinarum</Emphasis> induced by the toxic dinoflagellate <Emphasis Type="Italic">Heterocapsa circularisquama</Emphasis>

Mortality of the short-neck clam Ruditapes philippinarum exposed to the toxic dinoflagellate Heterocapsa circularisquama was studied under controlled conditions to clarify the mechanisms of recurrent mass deaths of clams occurring in western Japanese coastal areas. One-week mortality tests, involving three water temperatures, six H. circularisquama concentrations, and two clam body sizes, showed a significant increase in mortality with increasing temperature, H. circularisquama concentration, exposure duration, and body size (ANOVA, P < 0.01). Clam death was observed at concentrations as low as 50 cells/ml and temperatures as low as 15°C. Prior to death, clams showed an extreme retraction of their mantle edge and siphon, along with recurrent vomiting behavior before initiating a closure reaction followed by paralysis then death. Gills of paralyzed clams showed an important uptake of dye, implying gill damage. This study is the first laboratory evidence of bivalve mortality induced by H. circularisquama at low concentrations and low temperature, and the first report of differential effects according to the body size of bivalves.     

Influence of Water Temperature on Morphological Deformities in Cultured Larvae of Japanese Eel,Anguilla japonica,at Completion of Yolk Resorption

The occurrence of morphological deformities under different rearing water temperatures (18, 20, 22, 24, 26, 28, and 30 C) was examined in Japanese eel larvae. The rates of hatching and survival until yolk resorption at 22–26 C were higher than those at other water temperatures. Fertilized eggs never hatched at 18 and 30 C. The rates of occurrence of abnormal larvae reared at the water temperatures 24–28 C were lower than those at 20 or 22 C. Pericardial edema and lower jaw deformities occurred most frequently at lower temperatures (20 and 22 C). In contrast, the incubation temperature did not significantly affect the relative frequency of some neurocranial deformities and of spinal curvature. These results imply that the optimal temperatures for rearing Japanese eel eggs and embryos are 24–26 C from the viewpoints of survival and deformity.     

Amylopectin Staling of Cooked Milled Rices and Properties of Amylopectin and Amylose

Starches of waxy rices that showed varietal differences in hardness testing of cooked rice after amylopectin staling and high-amylose content (AC) rices differing in gel consistency (GC) and starch gelatinization temperature (GT) were studied to determine the factors related to varietal differences in amylopectin staling of cooked rice. Intermediate- and high-GT starches showed greater amylopectin staling of gelatinized rice by hardness testing values or differential scanning calorimetry (DSC) endotherm than did low-GT starches in both waxy and nonwaxy rices. Isoamylase-debranched amylopectins of waxy rices differed in the ratio of weight-average degree of polymerization (DP_w) fractions, but these fraction ratios were not simply related to differences in amylopectin staling of cooked rice. Among high-AC rices, amylopectin from low-GT starch was confirmed to have higher iodine affinity (2.3–2.5%) than amylopectin from intermediate-GT starches (1.7–1.8%), regardless of GC. Within high-AC starch of the same GT type, soft-GC rice corresponded with more A + B₁ DP_w 16–18 and less B₃ DP_w 150–200 fractions of debranched amylopectin and low DP_w of amylose. Amylopectin of amylose extender mutant of IR36 was confirmed to have a longer chain length than ordinary rice amylopectin: the debranched amylopectin has more B₂ DP_w 47–51 fraction, less A + B₁ DP_w fraction, but no B₄ fraction with DP_w > 200. Only high-AC amylopectin had debranched fraction with DP_w >120.     

Abnormal auxin distribution and poor berry setting (coulure) in grapes

A constant low auxin level was observed in a normally setting trimmed cluster of the tetraploid grape ‘Kyoho’ (Vitis vinifera L. × Vitis labrusca L.). The basipetal auxin transport in the trimmed cluster was always 2–3 times higher than the acropetal transport during the flowering-period. In a non-treated cluster, showing a tendency towards excessive berry abscission, the auxin level in the apical parts of the cluster fluctuated within the range of 20–70 times that of the auxin content at full bloom. The ratio of basipetal to acropetal auxin transport was nearly unity or less than unity.The results support the hypothesis of apical dominance and auxin gradient in the formation of an abscission zone.     

Monoaminergic Innervation of the Caudal Neurosecretory System of the Carp, Cyprinus carpio

Monoamine fluorescence was studied in the caudal neurosecretory system of eighty-four adult carp, Cyprinus carpio, of either sex. Some neurosecretory cells were surrounded with monoaminergic fluorescent varicosities, while others were not. The varicosities werc: also found adjacent to nerve terminals or capillaries in the urophysis. Noradrenaline, but not adrenaline or dopamine, was detected memically in the urophysis and the spinal cord. These results suggest that noradrenergic neurons seem to regulate both the synthesis and the release of neurosecretory material in the carp caudal neurosecretory system.     

Migration of warble fly larvae in the yak and optimum timing of ivermectin treatment

Sixty yaks were autopsied to determine the migration pattern of warble fly larvae. In August, first instars were observed in the body of yak for the first time. These larvae peaked in number in October. From November to February, second instars were detected and their number peaked in January. Third instars appeared in January and peaked in March. Forty-five yaks were administered with ivermectin: 15 animals in September, 15 in October and 15 in November. Between December and June, the number of warbles was checked by palpation. Although some warbles were observed in the September- and November-treated groups, no warbles were detected in the October-treated group. Treatment of yaks with ivermectin was most effective for warble fly in October.     

Optimal conditions for visualizing water-conducting pathways in a living tree by the dye injection method

To elucidate the water-conducting pathways in living trees by the dye injection method, suitable sample preparation procedures are needed. We evaluated quantitatively the properties and concentrations of three dyes (acid fuchsin, basic fuchsin and safranin) widely used for this purpose, and determined the optimal conditions required to avoid artifacts after dye injection into the sap stream of Pieris japonica D. Don. Among the dyes tested, an aqueous solution of acid fuchsin at a concentration of 0.1% or more was the most useful for delineating water movement. In non-transpiring stem segments, the vertical movement of acid fuchsin by capillarity and diffusion from the dye injection site was limited. However, acid fuchsin moved rapidly in the horizontal direction by capillarity and diffusion, and most xylem cells were stained within 2 h. A delay of more than 2 h between dye injection and examination of the tissues greatly reduces the precision of the method. Use of the dye injection method without appropriate, well-defined experimental procedures may give rise to misleading information about the functional water-conducting pathway in living trees.