Effects of cyclophosphamide on the kaolin consumption (pica behavior) in five strains of adult male rats

It is known that pica, the consumption of non-nutritive substances such as kaolin, can be induced by administration of toxins or emetic agents in rats. In the present study, we examined the effects of intraperitoneal (i.p.) administration of cyclophosphamide on pica behavior and on the concentration of 5-hydroxyindoleacetic acids (5HIAA) in cerebrospinal fluid (CSF) in the following five strains of adult male rats: Sprague Dawley (SD), Wistar, Fischer 344 (F344), Wistar-Imamichi (WI) and Long Evans (LE). Cyclophosphamide (25 mg or 50 mg/kg) was injected (i.p.) into the rats and kaolin and food intake were measured at 24 hr after injection. The animals were anesthetized with urethane (1 g/kg) at 3 hr after injection of cyclophosphamide, and CSF was collected from the cisterna magna. WI and LE rats clearly showed pica behavior as compared with the other strains. In LE rats, the concentration of 5HIAA in CSF also increased in a dose-dependent manner of cyclophosphamide. The pretreatment with ondansetron (5-HT(3) antagonist) restored both changes (kaolin consumption and 5HIAA levels) induced by cyclophosphamide. These results suggest that the LE rat is sensitive to cyclophosphamide, that pica induced by cyclophosphamide mimics many aspects of emesis including the serotonergic response in the central nervous system and that use of the pica model would be a practical method for evaluating the effects of antiemetic drugs in addition to the mechanism of emesis.     

DNA methylation status of bovine blastocyst embryos obtained from various procedures

DNA methylation is an important factor for the regulation of gene expression in early embryos. It is well known that the satellite I sequence is more heavily methylated in bovine somatic cell nuclear transfer (NT-SC) embryos than in embryos derived from in vitro fertilization (IVF). However, the methylation status of bovine embryos obtained by other procedures is not well known. To clarify DNA methylation levels of bovine embryos obtained from various procedures, we examined satellite I sequences in bovine blastocyst (BC) embryos derived from NT-SC, NT using embryonic blastomeres (NT-EM), in vivo (Vivo), IVF and parthenogenetic treatment (PA). Furthermore, in order to evaluate the efficacy of DNA demethylation by the NT procedure, we determined the DNA methylation levels in bovine embryos in which NT was recapitulated (Re-NT). Although the DNA methylation levels in the NT-SC embryos were higher than those in the other embryos, the NT-EM embryos exhibited lower DNA methylation levels. The satellite I sequence in the NT-SC embryos was more demethylated than that in the donor cells. Although the DNA methylation level in the individual NT-SC embryos showed variation, the full-term developmental efficacy of these embryos were not different. These findings suggest that the methylation level of the satellite I sequence at the BC stage is not related to the abnormalities of bovine embryos produced by NT-SC. There was no difference in methylation levels between Re-NT and NT-SC embryos. Our results indicated that the DNA methylation status differed among embryos produced by various methods and that at least some of the demethylation of the donor cell genome occurred in the recipient cytoplast after NT-SC, but the demethylation ability of the NT procedure was noted in the first NT but not in the second NT.     

Plasma high-mobility group box 1 (HMGB1) in dogs with various diseases: comparison with C-reactive protein

High-mobility group box 1 (HMGB1), a nonhistone chromosomal protein, has recently been suggested as a late mediator of the inflammatory cascade. Blood HMGB1 levels are increased in a number of human diseases, and HMGB1 has been suggested to be a useful marker for disease severity and prognosis. The objective of this study was to assess the clinical usefulness of HMGB1 in dogs. Plasma HMGB1 levels, as well as C-reactive protein (CRP), a typical canine inflammatory marker, were measured in dogs with various diseases, especially systemic inflammatory response syndrome (SIRS), and dogs that had undergone surgery. HMGB1 gradually increased and attained a maximum level 72 hr after surgery, whereas CRP increased rapidly, peaking at 24 hr. Although both HMGB1 and CRP levels were significantly increased in dogs with various diseases compared with the control dogs, no correlation was found between the HMGB1 and CRP values. HMGB1 levels in the SIRS group were significantly elevated compared with those in the non-SIRS group. However, the increase in HMGB1 levels above the reference range was not indicative of SIRS. Instead, the presence of increased HMGB1 and CRP levels above the reference ranges significantly affects the poor outcome of SIRS. The present study indicates that HMGB1 is a novel canine inflammatory marker and is distinct from CRP. However, the additional clinical value of HMGB1 measurement remains unclear, and further studies are warranted.     

Cloned porcine embryos can maintain developmental ability after cryopreservation at the morula stage

The aim of the present study was to clarify the overall efficiency of porcine somatic cell nuclear transfer (SCNT) by incorporating cryopreservation of the cloned embryos before transfer. The SCNT embryos reconstructed with preadipocytes and in vitro-matured (IVM) oocytes were cultured to harvest morula stage embryos; they were then subjected to delipation (removal of cytoplasmic lipid droplets) and vitrification. After warming and culture, the embryos developing to blastocysts were transferred to recipients to obtain cloned piglets. From 372 reconstructed embryos, 188 (50.5%) reached the morula stage and 117 (31.5%) developed to blastocysts after vitrification. Transfer of 98 (26.3%) morphologically normal blastocysts gave rise to 6 (1.6%) piglets, including 1 stillborn. The efficiency of the cloned piglet production was comparable with that obtained using SCNT embryos without cryopreservation (2.7%, 17/635). Here, we demonstrate that porcine somatic cell cloning can be performed without a significant reduction in efficiency even when the SCNT embryos are cryopreserved before transfer.     

Lesion-based analysis of leaf blast suppression in mixture of rice cultivar and a resistant near-isogenic line

Leaf blast suppression in multilines was evaluated based on the number of susceptible lesions observed in a pure stand of susceptible rice cultivar Sasanishiki, and in 1 : 1 and 1 : 3 mixtures of Sasanishiki and a resistant near-isogenic line, Sasanishiki BL4 or BL7, from 1998 to 2001. The number of lesions first observed in fields in the 1 : 1 and 1 : 3 mixtures were close to theoretical numbers calculated using the number of lesions observed in the pure stands and the ratios of the susceptible Sasanishiki in the mixtures. The ratio of the number of lesions in the 1 : 1 and 1 : 3 mixtures to the number in the pure stand was 0.29 and 0.09, respectively. The relationship between these ratios and the ratios of susceptible Sasanishiki in mixtures was defined in an equation to estimate the degree of leaf blast suppression. Validation studies for the ratios of the number of lesions in the 1 : 1 and 1 : 3 mixtures to the number in the pure stand were conducted in two different locations and showed that the ratios are almost acceptable. The calculated autoinfection to alloinfection ratio was 1.3 and 1.4 in the 1 : 1 and 1 : 3 mixtures, respectively, suggesting that the calculated ratio will affect the degree of leaf blast suppression. Thus, predictors were obtained to estimate leaf blast suppression for effective blast control in multilines.     

Isolation and characterization of lectins from the AG-D group of binucleate <Emphasis Type="Italic">Rhizoctonia</Emphasis> species

Isolates from 18 anastomosis groups (AGs) of binucleate Rhizoctonia were screened for lectin activity. Eight AGs (AG-B, AG-D, AG-F, AG-G, AG-H, AG-I, AG-R and AG-U) had low to moderate lectin activities. Among these, members of AG-D and AG-I had the highest activity. Partially purified lectins from AG-D preferentially agglutinated human blood type A to type B and O. Mucin and galactose were the most potent inhibitors among the tested carbohydrates. The molecular masses of these lectins ranged from 12.7 kDa for the monomer to 62 kDa for the pentamer type. Proline, alanine, glutamic acid, aspartic acid, leucine, threonine, serine and tyrosine were the major amino acid components of these lectins. Lectins from AG-D were stable at 4–50°C and from pH 6.0 to 10.0. When assayed with isoelectric focusing, these lectins gave bands at pI 9.30. Specificity of lectins from AG-D to galactose and its derivatives suggest a possible recognition role in this fungal species.     

Optimal application timing of simeconazole granules for control of rice kernel smut and false smut

We investigated the optimal timing of simeconazole (RS-2-(4-fluorophenyl)-1-(1H-1,2,4-triazol-1-yl)-3-trimethylsilylpropan-2-ol) application for controlling rice kernel smut in field trials in Miyagi Prefecture, Japan, using formulations of simeconazole (1.5% granules). The field tests revealed that a submerged application of simeconazole granules (450–600 g ai/ha) at 1–5 weeks before heading was highly effective against kernel smut, with treatments 1–2 weeks before heading being the most effective. Submerged application of the fungicide at 2–5 weeks before heading was also highly effective against false smut, with treatment 3 weeks before heading being the most effective. These periods overlap the timing for optimal application of simeconazole to control rice sheath blight and ear blight. Consequently, we concluded that treatment with simeconazole 2–3 weeks before heading can be a useful tool for controlling all four diseases.     

A cat with acute myeloblastic leukemia without maturation (M1) treated with combination chemotherapy

A 2-year-old domestic shorthair cat was presented to us with decreased activity and anorexia. Hematologic findings revealed a mild non-regenerative anemia, thrombocytopenia, and leukocytosis with an increase in blast cells. Bone marrow aspirates also revealed a marked increase of blasts. The blastic cells were shown to be positive for peroxidase. Acute myeloblastic leukemia without maturation (M1) was diagnosed according to the FAB classification. Chemotherapy was initiated with cyclophosphamide, vincristine, prednisolone, and cytosine arabinoside. The cat responded partially. In total, the cats were given 7 blood transfusions. The cat died 14 weeks after first being presented to us.     

Identification of bovine dendritic cell phenotype from bovine peripheral blood

Dendritic cells (DCs) are professional antigen presenting cells, which initiate primary immune responses and also play an important role in the generation of peripheral tolerance. There is no reliable method established for the isolation of bovine peripheral blood DCs, and furthermore, the phenotypes and the functions of bovine DCs are still not fully clear. In the present study, we have attempted to identify bovine peripheral blood DCs by negative-selection. In bovine peripheral blood mononuclear cells (PBMC), we have newly characterized the phenotype of DCs, which is CD11c+/CD172a+. These cells display features of myeloid type DCs. In the thymic medulla, CD11c+/CD172a+ cells were also present and CD1+/CD172a+ cells were additionally detected as a population of DCs. The data suggest that one of the bovine DCs phenotypes from PBMC is derived from myeloid lineages lacking a CD1 molecule, which then drift to several tissues, and that they then may express a CD1 molecule upon their functional differentiation.