Evaluation of a recombinant measles virus expressing hepatitis C virus envelope proteins by infection of human PBL-NOD/Scid/Jak3null mouse

In this study, we infected NOD/Scid/Jak3null mice engrafted human peripheral blood leukocytes (hu-PBL-NOJ) with measles virus Edmonston B strain (MV-Edm) expressing hepatitis C virus (HCV) envelope proteins (rMV-E1E2) to evaluate the immunogenicity as a vaccine candidate. Although human leukocytes could be isolated from the spleen of mock-infected mice during the 2-weeks experiment, the proportion of engrafted human leukocytes in mice infected with MV (10³–10⁵ pfu) or rMV-E1E2 (10⁴ pfu) was decreased. Viral infection of the splenocytes was confirmed by the development of cytopathic effects (CPEs) in co-cultures of splenocytes and B95a cells and verified using RT-PCR. Finally, human antibodies against MV were more frequently observed than E2-specific antibodies in serum from mice infected with a low dose of virus (MV, 10⁰–10¹ pfu, and rMV-E1E2, 10¹–10² pfu). These results showed the possibility of hu-PBL-NOJ mice for the evaluation of the immunogenicity of viral proteins.     

Hydrogen peroxide produced by a low‐molecular‐weight compound in milk with high electrical conductivity in dairy cows

In dairy cows, hydrogen peroxide (H₂O₂) produced from a low‐molecular‐weight compound in milk from inflamed quarters was lower than that in milk from un‐inflamed quarters. In milk of delivery grade, characteristics of H₂O₂ production in milk with high electrical conductivity (EC) were examined in this study. Milk samples were collected from a total of 230 cows at 1‐month intervals, and the EC of skimmed milk was determined. Based on the highest and the lowest EC of a cow's quarter milk, the inter‐quarter difference of ≥0.6 mS/cm (mean + t_0.01 SE) was taken as a high EC. Milk with high EC was found in 52 quarters. In cows with milk of high EC, H₂O₂ production in milk with normal EC was higher than that in milk with high EC in the same animal but was lower than that in the control population. In milk with high EC, the decrease of H₂O₂ production correlated with the increase in EC. The production of H₂O₂ decreased in particular when the inter‐quarter difference exceeded 0.8 mS/cm. In milk collected from the same quarter 1 month before, EC changed from normal to high, and H₂O₂ production decreased. In milk from the other three quarters, EC remained normal and H₂O₂ production remained unchanged. We concluded that milk with high EC appeared in low H₂O₂‐producing cows. The results suggest that the degree of decrease in H₂O₂ production reflects the extent of quarter abnormality.     

Simultaneous detection by multiplex PCR of the high-temperature-growing Pythium species: P. aphanidermatum, P. helicoides and P. myriotylum

The objective of this study was to develop a multiplex PCR detection method for the high-temperature-growing pathogens Pythium aphanidermatum, P. helicoides and P. myriotylum. Species-specific primer pairs were designed that targeted the rDNA ITS regions. The multiplex PCR was constructed with a universal primer pair for eukaryotes directed at the 18S rDNA as a positive control, in addition to the three species-specific primer pairs. When the multiplex PCR was applied to naturally infested soils, the expected species were reliably identified, suggesting that the method is suitable for the detection of the three Pythium pathogens in environmental samples.     

Unstable side population phenotype of mouse spermatogonial stem cells in vitro

Stem cells of the side population (SP) phenotype are found in many self-renewing tissues and can be identified by their unique ability to effectively exclude the dye Hoechst 33342. We previously established a method for expanding spermatogonial stem cells (SSCs) in vitro, but the frequency of SSCs is only about 1 to 2%, limiting detailed SSC analyses. In this study, we sought to isolate SSCs from in vitro cultures by exploiting their ability to exclude Hoechst 33342. In contrast to the findings of previous in vivo studies, we found that SP cells developed in a stochastic manner in vitro. Moreover, SP cells in culture were not enriched in SSCs, but they were interconvertible with non-SP cells. Although SP cells were consistently found in testes after transplantation of cultured cells, they were not enriched in SSCs. These results show that SSCs have an unstable SP phenotype and provide evidence that SSCs change their phenotype characteristics in response to their microenvironment.     

Surgical closure of an atrial septal defect using cardiopulmonary bypass in a cat

Objective: To describe surgical repair of a large atrial septal defect (ASD) in a cat. Study Design: Clinical report. Animal: A 3‐year‐old, 3.3 kg, intact male Japanese domestic short‐haired cat. Methods: A 10.2‐mm‐diameter ASD detected by echocardiography was surgically corrected because pulmonary vascular resistance‐to‐systemic vascular resistance ratio (Q_p/Q_s) was 3.2. Using cardiopulmonary bypass (CPB), open surgical repair was achieved with an expanded polytetrafluoroethylene (e‐PTFE) graft. The priming volume of the CPB circuit was minimized by cutting the CPB tubing, and partially replacing the priming fluid with whole cat blood. To prevent hemodilution associated with use of cardioprotective agents, surgery was performed on the beating heart. Results: At 1‐year echocardiographic evaluation, the repair was intact, and at 3 years, the cat was alive without need of medication. Conclusions: Large ASD in a cat can be repaired using e‐PTFE under CPB.     

Establishment of an in vitro culture model to study milk production and the blood–milk barrier with bovine mammary epithelial cells

This study attempted to establish a culture model to recreate the milk production pathway in bovine mammary epithelial cells (BMECs). BMECs were isolated from Holstein cows (nonlactating, nonpregnant, and parous) and were stored by cryopreservation. To separate the apical and basolateral compartments, BMECs were cultured on a cell culture insert with a collagen gel in the presence of bovine pituitary extract and dexamethasone to induce milk production and tight junction (TJ) formation. The culture model showed the secretion of the major milk components, such as β‐casein, lactose, and triglyceride, and formed less‐permeable TJs in BMECs. Moreover, the TJs were distinctly separated from the apical and basolateral membranes. Glucose transporter‐1, which transports glucose into the cytoplasm through the basolateral membrane, localized in the lateral membrane of BMECs. Toll‐like receptor‐4, which binds to lipopolysaccharide in the alveolar lumen in mastitis, localized in the apical membrane. Beta‐casein was mainly localized near the Golgi apparatus and the apical membrane. Moreover, milk components were almost secreted into the upper chamber of the cell culture insert. These findings indicate that this model has clear cell polarity as well as in vivo and is effective to study of milk production and the blood–milk barrier in lactating BMECs.     

Inferring phenotypic causal structure among farrowing and weaning traits in pigs

Direct selection for litter size or weight at weaning in pigs is often hindered by external interventions such as cross‐fostering. The objective of this study was to infer the causal structure among phenotypes of reproductive traits in pigs to enable subsequent direct selection for these traits. Examined traits included: number born alive (NBA), litter size on day 21 (LS21), and litter weight on day 21 (LW21). The study included 6,240 litters from 1,673 Landrace dams and 5,393 litters from 1,484 Large White dams. The inductive causation (IC) algorithm was used to infer the causal structure, which was then fitted to a structural equation model (SEM) to estimate causal coefficients and genetic parameters. Based on the IC algorithm and temporal and biological information, the causal structure among traits was identified as: NBA → LS21 → LW21 and NBA → LW21. Owing to the causal effect of NBA on LS21 and LW21, the genetic, permanent environmental, and residual variances of LS21 and LW21were much lower in the SEM than in the multiple‐trait model for both breeds. Given the strong effect of NBA on LS21 and LW21, the SEM and causal information might assist with selective breeding for LS21 and LW21 when cross‐fostering occurs.     

Effect of boiled barley-rice-feeding in hypercholesterolemic and normolipemic subjects

Barley contains approximately 10% dietary fiber and is easily cooked with rice, the dominant cereal in Japan, to increase the intake of dietary fiber. This research involved three experiments to examine the influence of barley on blood lipids in human subjects. All subjects received a boiled barley-rice (50/50 w/w mix) supplement two times per day in place of rice for 2 or 4 weeks. In the normolipemic subjects, serum lipids were unaffected by the ingestion of barley for 4 weeks. In twenty hypercholesterolemic men aged 41 ± 5 years, the ingestion of barley was associated with a significant fall in serum total cholesterol, LDL-cholesterol, phospholipids and LDL and VLDL-lipoproteins. In seven mildly hypercholesterolemic women aged 56±7 years, a significant improvement of serum lipid profiles was observed. The present study suggests the possibility that the ingestion of barley-rice could lower serum lipids in hypercholesterolemic subjects.     

Effect of free-air CO2 enrichment on the storage of carbohydrate fixed at different stages in rice (Oryza sativa L.)

Increasing global atmospheric CO₂ concentrations are expected to influence crop production. To investigate the effect on rice (Oryza sativa L.), plants were grown under ambient CO₂ (AMB) or free-air CO₂-enrichment (FACE) at CO₂ concentrations ranged from 275 to 365 μmol mol⁻¹ above AMB. We supplied ¹³CO₂ to the plants at different growth stages so we could examine the contribution of carbohydrate stored during the vegetative stage or newly fixed carbohydrate produced during the grain-filling stage to ear weight at grain maturity. In plants supplied with ¹³C at the panicle-initiation or pre-heading stages, plants grown under FACE had more starch in the stems at heading, but there was no difference in stem ¹³C content. Furthermore, there were no differences between treatments in whole-plant ¹³C contents at heading and grain maturity. In contrast, plants supplied with ¹³C at the grain-filling stage had more ¹³C in the whole plant and the ears at grain maturity under FACE than under AMB, indicating that the increased amount of photosynthate produced at the grain-filling stage under CO₂ enrichment might be effectively stored in the grains. Furthermore, regardless of when the ¹³C was supplied, plants had more ¹³C in starch in the ears at grain maturity under FACE than under AMB. Therefore, CO₂ enrichment appears to promote partitioning of photosynthate produced during both vegetative and grain-filling stages to the grains.     

Assessment of the water quality of two rivers in Hanoi City and its suitability for irrigation water

The To Lich and Kim Nguu Rivers in Hanoi City are the main sources of irrigation water for suburban agricultural land and fish farm. Wastewater from the industrial plants located along these rivers has been discharged, and has degraded the water quality of the rivers. This study describes the chemical properties of water from the rivers, focusing on heavy metal pollution and the suitability of water quality for irrigation water. Water from the rivers was heavily polluted with organic matter and heavy metals such as Pb, Cu, Zn, Cr, Cd and Ni. Dissolved oxygen, chemical oxygen deman, and total suspended solids, and the concentrations of all heavy metals exceeded the Vietnamese standard for surface water quality in all investigated sites. The concentrations of some heavy metals such as Cu, Cd, Cr and Ni were above the internationally recommended WHO maximum level for irrigation water. A wide variation in the heavy metal concentration of water due to metal types is the result of wastewater discharged from different industrial sources.