Testing the Suitability of the DNDC Model for Simulating Long-Term Soil Organic Carbon Dynamics in Japanese Paddy Soils

The suitability of the DeNitrification-DeComposition (DNDC) model for simulating long-term changes in the content of soil organic carbon (SOC) was validated using 5 sites for long-term experiments related to Japanese paddy soils. Since the model could not simulate crop growth adequately, several crop growth parameters provided by the model as default were changed to adjust crop growth to the observation. Overall, the changes in the content of SOC with time simulated by DNDC using adjusted crop parameters, agreed well with the observation in 9 plots from 5 experimental sites during the 16 to 22-year period of the experiment. The good performance of the decomposition sub-model in the DNDC was verified in the long-term SOC decomposition in paddy soils as well as in upland soils reported in previous studies. However, the simulated SOC did not agree well with the observation in some plots, especially in soils with a very low SOC content, suggesting that care should be exercised when applying the model to soils with a very low SOC content. Moreover, careful tuning of crop growth parameters should be promoted for better simulation, and detailed information about farm management required for input parameters is often difficult to obtain, especially in long-term experiments. In conclusion, the DNDC model is an effective tool for simulating long-term SOC dynamics in paddy soils. The unique kinetic scheme "anaerobic balloon" in the model may play an important role in successful simulation of SOC dynamics in paddy soils that are water-logged during the rice cropping period. This scheme may be helpful for modifying the other turnover models of soil organic matter for use for paddy soils, too.     

Comparison between immunohistochemistry and genetic clonality analysis for cellular lineage determination in feline lymphomas

Clinical application of genetic clonality analysis by PCR has been available in feline lymphoma. However, it is in under dispute whether the analysis can be applied for cellular lineage determination. To evaluate utility of the analysis for lineage determination, the results between immunohistochemistry and the genetic analysis were compared. Based on the result with immunohistochemistry, sensitivity of the primer for IgH was 89% and specificity was 75%. Sensitivity of the primer for TCRγ was 25% and specificity was 100%. Cross-lineage IgH rearrangement was found in 25% of T-cell lymphomas. The present study suggests that the genetic analysis had better be applied as not a definite but an adjunctive tool for lineage determination in feline lymphomas.     

The prognostic significance of minimal residual disease in the early phases of chemotherapy in dogs with high-grade B-cell lymphoma

The prognostic significance of minimal residual disease (MRD) in the early phases of chemotherapy was examined in 36 dogs with multicentric high-grade B-cell lymphoma. Sequences of immunoglobulin heavy chain (IgH) gene fragments from lymphoma cells were amplified and used to design allele-specific primers and probes for real-time PCR. The dogs were treated with a 6-month modified version of the University of Wisconsin–Madison chemotherapy protocol (UW-25) and evaluated for the MRD level at weeks 6 and 11 of UW-25.Of the 31 dogs that remained on the protocol at week 11, 14 were found to be MRD negative (<10 tumour cells/10⁵ peripheral blood mononuclear cells [PBMCs]), whereas the other 17 were MRD positive (?10 tumour cells/10⁵ PBMCs). The progression-free survival of the dogs with MRD-negative status at week 11 (median, 337 days) was significantly longer than that of the MRD-positive dogs at the same time point (median, 196 days) (P = 0.0002). These results indicate the clinical significance of MRD as a prognostic marker in the early phase of chemotherapy.     

Changes in soil properties after afforestation in Horqin Sandy Land,North China

We studied the changes in soil properties after afforestation on desertification-affected sandy soils to estimate how much time would be required for soils to recover enough for use in sustainable food production. We surveyed soils near and within 3-, 9-, and 19year- old plantations of poplar (Poplus simonii) in the central part of Naiman County, eastern Inner Mongolia, China. Changes in the soil properties following afforestation included an accumulation of fine particles (clay + silt) and soil organic carbon (SOC) in the surface horizons. The contents of fine particles and SOC increased slowly in the first 9-year period and then rapidly between 10 and 19 years, being higher at concave than convex sites. Soil parameters such as available moisture level, amounts of available N and available P, and CEC that control soil fertility showed a similar trend to that of the contents of fine particles and SOC. The contents of fine particles and SOC were higher at the windward edge than in the center of the 19-year-old poplar plantation, suggesting that the accumulation of fine particles was caused by the decrease in wind velocity due to the presence of vegetation. The increase in the SOC content may be caused by the increased carbon input to soils from the vegetation and by the deposition of fine particles with a higher C concentration than that of native sandy soils. Soil fertility, represented by the amounts of available N in the upper 20 cm layer of the soil, recovered after 19 years under poplars, and was similar to that of adjacent fertile cropland. However, the amount of available N under plantations younger than 10 years was lower than that in cropland soils, suggesting that a period of between 10 and 20 years is required for soils to recover from desertified conditions and be utilized for intensive crop farming once again.     

Effect of mosapride on prednisolone-induced gastric mucosal injury and gastric-emptying disorder in dog

Previous report demonstrated that prokinetic agent mosapride has anti-ulcerogenic action in rat-indomethacin gastric mucosal injury model. Here, we assessed the prophylactic effect of mosapride on gastric mucosal injury and emptying disorder induced by prednisolone in dogs. Crossover study design was employed. Six healthy beagles were administered prednisolone alone (2 mg/kg, twice a day [BID] subcutaneously) and prednisolone with mosapride (1 mg/kg, BID, orally), followed by an interval of at least 6 weeks. In each treatment, gastric mucosal injury was scored endoscopically according to the modified Lanza scale, and gastric emptying was assessed with (13)C-octanoic acid breath test. The incidence of gastrointestinal adverse events was also investigated. Coadministration of mosapride with prednisolone significantly (P<0.05) reduced the gastric mucosal injury score (mean ± SD, 17.67 ± 6.96), compared with that of prednisolone treatment alone (25.50 ± 13.03). Prednisolone treatment delayed the half-emptying time (184 ± 45 min) compared with that of controls (137 ± 19 min), and coadministration of mosapride improved this gastric-emptying delay (143 ± 29 min). Furthermore, the incidence of the gastrointestinal adverse event vomiting became less frequent upon coadministration with mosapride. In addition to its prokinetic action, our study suggests that mosapride has an anti-ulcerogenic action in dogs. The use of mosapride in combination with prednisolone is effective for attenuating prednisolone-induced gastrointestinal adverse events.     

Molecular cloning and expression analysis of the canine chemokine receptor CCR9

The chemokine receptor CCR9, which interacts with the thymus-expressed chemokine TECK/CCL25, contributes to the localization of lymphocytes to the small intestine, and is implicated in the development of human inflammatory bowel disease (IBD); however, their role in canine IBD is unknown. The objective of this study was to isolate cDNA encoding CCR9 and to investigate CCR9 expression in normal canine tissues and lymphoid cell lines. The complete open reading frame contained 1104 bp, encoding 367 amino acids, with 85% and 81% identity to human and mouse homologs, respectively. CCR9 mRNA was detected in all tissues investigated with the highest expression level in the small intestine. CCR9 mRNA was also expressed in GL-1, a canine B cell leukemia cell line, but not in CLBL-1, a canine B cell lymphoma cell line. Immunoblot and flow cytometry analyses of these cell lines using an anti-human CCR9 monoclonal antibody revealed that CCR9 protein expression was detected only in GL-1, indicating the cross-reactivity of the antibody. Using the antibody, flow cytometry showed that the proportions of CCR9(+) cells were small (mean, 4.88%; SD, 2.15%) in the normal canine PBMCs. This study will be useful in understanding canine intestinal immunity and the immunopathogenesis of canine IBD.     

Essential thrombocythemia in a dog

A two-year old male Welsh Corgi was referred for persistent thrombocytosis and occasional seizure. Hematological findings indicated marked thrombocytosis, eosinophilia, basophilia and moderate anemia. Bone marrow examination revealed marked megakaryocytic hyperplasia with morphologic abnormality. A diagnosis of essential thrombocythemia was made and the treatment was initiated with combination chemotherapy and maintained by prednisolone and busulfan. The dog successfully achieved complete remission on 100 days after initial presentation and has been good in health without chemotherapy since then.     

Trace toxic elements in agricultural soil and sediment in the biggest estuarine area,northern Vietnam

Paddy and Water Environment - Soil quality, especially its toxic elements content, plays an important part in clarifying the sustainability of an estuarine ecosystem. In this study, six toxic...