Influence of certain soybean antinutritional factors supplemented to a casein-based semipurified diet on intestinal and liver morphology in fingerling rainbow trout <Emphasis Type="Italic">Oncorhynchus mykiss</Emphasis>

To investigate the cause of morphological changes occurring in the liver and intestine of rainbow trout Oncorhynchus mykiss fed defatted soybean meal (SBM)-based non-fish meal diets, morphological observations were conducted on fish fed casein-based semipurified diets supplemented with soybean antinutritional factors (soya saponin, soya isoflavone, soya lectin, oligosaccharide, Ca-phytate and their mixture). Hepatocytes and the epithelial cells in the hepatic ducts were not atrophied in any of the treatments. Lack of microvilli and pinocytotic vacuoles, and fatty degeneration of the epithelial cells were observed in the distal intestine of fish fed diets containing soya saponin. The proliferation of connective tissue in the mucosal folds and submucosa was shown in the distal intestine of fish fed the diet containing all substances including lectin. These results suggest that both saponin and lectin are the responsible factors in SBM for the occurrence of morphological changes of the distal intestine in rainbow trout fed SBM-based diets.     

Isolation and characterization of an additional crustacean hyperglycemic hormone from the greasyback shrimp <Emphasis Type="Italic">Metapenaeus ensis</Emphasis>

Crustacean hyperglycemic hormone (CHH) is released from the X-organ/sinus gland complex located in the eyestalks. In this study, the most abundant CHH in the sinus gland of the greasyback shrimp Metapenaeus ensis was purified by reversed-phase HPLC and identified by N-terminal amino acid sequencing. Although two CHH molecules (Mee-CHH-A and Mee-CHH-B) have already been identified from M. ensis by cDNA cloning, this study revealed the presence of an additional CHH peptide based on differences in the N-terminal amino acid sequences of the CHH-A and CHH-B. Therefore, this novel CHH was designated as Mee-CHH-C. A cDNA encoding the Mee-CHH-C precursor was cloned by RT-PCR coupled with 5′- and 3′-RACE, and it was found that the mature Mee-CHH-C consisted of 72 amino acid residues containing 6 conserved cysteine residues and possessed an amidated C terminus. Mee-CHH-C had 62 and 68% identities with Mee-CHH-A and Mee-CHH-B, respectively, and was highly homologous to CHHs characterized from other penaeid shrimp species. The hyperglycemic activity of Mee-CHH-C was examined by an in vivo bioassay using the kuruma prawn Marsupenaeus japonicus. Injection of Mee-CHH-C increased hemolymph glucose levels significantly and dose-dependently. These results indicate that Mee-CHH-C is possibly one of the major molecules in M. ensis that regulate glucose levels in the hemolymph.     

Protein metabolism in rice seedling

The relationship between protein synthesis and degradation in germinating rice seed were studied with protein synthetic inhibitors. Both DNP and 8-AG inhibited the degradation of glutelin, the major storage protein in rice seed, while the inhibitors had no direct effect in the activity of rice seed proteinllse in vitro. The prevention can be partly ascribed to the Inhibition of proteinase synthesis because the inhibitors depressed the increase in proteinase activity during germination. When DNP treatment was started at the onset of germination, the degradation of glutelin in the endosperm was seriously inhibited and the endosperm remained rigid over 9 days of incubation at 30°C. In contrast, the inhibition was less efficient clent when the treatment was started in the later stage. It is suggested that the degradation of the storage protein in rice seed depends on the synthetic process of the hydrolytic enzymes which increase during germination. disintegrate the compartmentation of the endosperm and allow the storage proteins to come in contact with the existing proteinases     

Studies on the effect of the paddy field soil kept under upland condition on the yield of rice

In Japan, the extent under paddy is approximately three million hectares and the average yield per hectare is about 3000 kg, though high yield gives as much as over 7000 kg per hectare. It is at present a serious problem as to what methods we can use to obtain a high yield of rice. Generally, in well-drained paddy fields where the system of double-cropping is practised, rice is cultivated under a flooded condition in summer, and upland crops such as barley or wheat is cultivated under upland condition in other seasons.     

Annual reproductive cycle of the greasyback shrimp Metapenaeus ensis in Ise Bay,Japan

The greasyback shrimp Metapenaeus ensis is widely distributed along the coast of India and the West Pacific where it is an important fisheries species. We have examined seasonal changes in ovarian development, spermatogenesis, and mating of Me. ensis in histological studies and by external observations on specimens collected in Ise Bay, its northernmost habitat. Ovaries were found to be previtellogenic from February to May, with the first signs of development being the accumulation of yolk in oocytes in late May. Ovarian shadow ratios were high during the period late July to mid-September. The formation of cortical rods in the peripheries of oocytes and germinal vesicle breakdown were observed in ovaries from late June to September. Male shrimps had sperm in the testes during the period early June to early October, and female shrimps had spermatophores in spermatheca after early July. In late July, some post-spawn female shrimps had exogenous vitellogenic oocytes in their ovaries, indicating that ovarian development had been repeated in preparation for the next spawning. Ovarian shadow ratios, which were positively correlated with gonadosomatic indices and ovarian development, seem to be a useful marker to determine ovarian development. Our results indicate that mating in Me. ensis started in early July and that the spawning season ranged from July to September with more than two cycles of spawning in Ise Bay.

     

Height growth,diameter-height relationships and branching architecture of <Emphasis Type="Italic">Pinus massoniana</Emphasis> and <Emphasis Type="Italic">Cunninghamia lanceolata</Emphasis> in early regeneration stages in Anhui Province,eastern China: effects of light intensity and regeneration mode

To determine the growth strategies during early regeneration stages of two major coniferous species (Pinus massoniana     

Neuronal ceroid-lipofuscinosis in longhaired Chihuahuas: clinical, pathologic, and MRI findings

Neuronal ceroid-lipofuscinosis (NCL) is a rare group of inherited neurodegenerative lysosomal storage diseases characterized histopathologically by the abnormal accumulation of ceroid- or lipofuscin-like lipopigments in neurons and other cells throughout the body. The present article describes the clinical, pathologic, and magnetic resonance imaging (MRI) findings of the NCL in three longhaired Chihuahuas between 16 mo and 24 mo of age. Clinical signs, including visual defects and behavioral abnormalities, started between 16 mo and 18 mo of age. Cranial MRI findings in all the dogs were characterized by diffuse severe dilation of the cerebral sulci, dilated fissures of diencephalons, midbrain, and cerebellum, and lateral ventricular enlargement, suggesting atrophy of the forebrain. As the most unusual feature, diffuse meningeal thickening was observed over the entire cerebrum, which was strongly enhanced on contrast T1-weighted images. The dogs' conditions progressed until they each died subsequent to continued neurologic deterioration between 23 mo and 24 mo of age. Histopathologically, there was severe to moderate neuronal cell loss with diffuse astrogliosis throughout the brain. The remaining neuronal cells showed intracytoplasmic accumulation of pale to slightly yellow lipopigments mimicking ceroid or lipofuscin. The thickened meninges consisted of the proliferation of connective tissues with abundant collagen fibers and mild infiltration of inflammatory cells suggesting neuroimmune hyperactivity. Although the etiology of this neuroimmune hyperactivity is not currently known, MRI findings such as meningeal thickening may be a useful diagnostic marker of this variant form of canine NCL.     

Fetal and neonatal goiter in cynomolgus monkeys following administration of the antithyroid drug thiamazole at high doses to dams during pregnancy

To evaluate morphologic alterations in the thyroid gland in the second generation in cynomolgus monkeys, pregnant dams were exposed to high doses of thiamazole. In Experiment A, dams received thiamazole intragastrically via a nasogastric catheter from gestation day (GD) 50 to GD 150 or on the day before delivery. Initially, the dose level was 20 mg/kg/day (10 mg/kg twice daily); however, the dose level was subsequently decreased to 5 mg/kg/day (2.5 mg/kg twice daily), since deteriorated general conditions were observed in two dams. Six out of seven neonates died on the day of birth. The cause of neonatal death was tracheal compression and suffocation from goiter. The transplacental exposure to thiamazole affected the fetal thyroid glands and induced goiter in all neonates. The surviving neonate was necropsied 767 days after discontinuation of thiamazole exposure and showed reversibility of the induced changes. In Experiment B, dams were intragastrically administered thiamazole at 5 mg/kg/day (2.5 mg/kg twice daily) for treatment periods from GDs 51 to 70, 71 to 90, 91 to 110, 111 to 130 and 131 to 150. All fetuses showed enlarged thyroid glands but were viable. Histopathologically, hypertrophy and/or hyperplastic appearance of the follicular epithelium of the thyroid gland was observed at the end of each treatment period. The most active appearance of the follicular epithelium, consisting of crowded pedunculated structure, was demonstrated at end of the treatment period from GD 131 to 150. This is the first report on the morphology of fetal and neonatal goiter in the cynomolgus monkey.