Classification of lactic acid bacteria isolated from chigee and mare milk collected in Inner Mongolia

One hundred and seventeen isolates from chigee and 191 isolates from mare milk collected in Inner Mongolia were classified into six and 10 groups, respectively, based on the protein profiles obtained by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE). A dendrogram on the basis of the molecular sizes of the protein bands was drawn and the similarity among the groups ranged from 96% to 44%. Representative isolates from all groups were identified by 16S rDNA sequencing and a phylogenetic tree was drawn. Furthermore, the results of carbohydrate fermentation tests of all groups were compared with those obtained by 16S rDNA sequencing and SDS‐PAGE analyzes. The isolates from chigee consisted of mainly Lactobacillus sp., Lactobacillus (Lb.) plantarum, Lb. pentosus and Lactococcus (Lc.) lactis ssp. cremoris were isolated at the rates of 48, 33 and 19%, respectively. The isolates from mare milk consisted of coccus, namely, Leuconostoc (Leuc.) mesenteroides, Leuc. pseudomesenteroides, Lc. garvieae, Lc. lactis ssp. lactis, Streptococcus (Sc.) parauberis and Enterococcus (Ec.) faecium. The isolation rates were 45, 19, 7, 8, 16 and 6%, respectively. The results demonstrated that the species isolated from chigee were different from those in mare milk.     

Evaluation of the live vaccine efficacy of virulence plasmid-cured,and phoP- or aroA-deficient Salmonella enterica serovar Typhimurium in mice

We evaluated the protective efficacy of 94-kb virulence plasmid-cured, and phoP- or aroA-deficient strains of Salmonella enterica serovar Typhimurium (ΔphoP or ΔaroA S. Typhimurium) as oral vaccine candidates in BALB/c mice. Two weeks after the completion of 3 oral immunizations with 1 × 10⁸ colony-forming units (CFU) of virulence plasmid-cured, and ΔphoP or ΔaroA S. Typhimurium at 10-day intervals, S. Typhimurium lipopolysaccharide (LPS)-specific mucosal secretory immunoglobulin A (s-IgA) antibody titers were detected in the cecal homogenate, bile and lung lavage fluid, but not in the intestinal lavage fluid. In addition, the increases in S. Typhimurium LPS-specific immunoglobulin G (IgG) and IgA antibody titers in the serum were also observed 2 weeks after completing 3 oral immunizations with virulence plasmid-cured, and ΔphoP or ΔaroA S. Typhimurium. The series of 3 oral immunizations protected the mice against an oral challenge with 5 × 10⁸ CFU of the virulent strain of S. Typhimurium, suggesting that both the virulence plasmid-cured, and ΔphoP and ΔaroA S. Typhimurium strains are promising candidates for safe and effective live S. Typhimurium vaccines.     

Serum cystatin C concentration can be used to evaluate glomerular filtration rate in small dogs

Serum cystatin C levels (CysC) are used in human medicine to document progressive kidney failure. Although CysC are not thought to be useful for the diagnosis of kidney dysfunction in dogs, there has been no specific consideration of body weight as a confounding issue. The aim of this study was to assess that the utility of CysC for the diagnosis of decreased glomerular filtration rate (GFR) in smaller vs. larger dogs. In clinically healthy dogs, serum creatinine (Cre) and CysC correlate directly with body weight; we found that dogs weighing <20 kg had significantly lower CysC than those weighing ≥20 kg (0.27 ± 0.07 vs. 0.34 ± 0.05 mg/l, respectively, P<0.001). In dogs weighing <20 kg, CysC had superior diagnostic accuracy for the detection of mildly decreased plasma iohexol clearance (PCio) (<1.8 ml/min/kg) compared with Cre (sensitivity 100% vs. 80.9% and specificity 100% vs. 85.7%); this was not true for dogs weighing ≥20 kg. Additionally, using a cut-off PCio of <1.8 ml/min/kg, the area under receiver-operating characteristics curve (AUC) of CysC was significantly higher than that of Cre in dogs weighing <20 kg (P<0.05); this was not true for dogs weighing ≥20 kg (P=0.695). In conclusion, CysC is a useful marker for the detection of a mild decreasing GFR compared with Cre in dogs weighing <20 kg.     

Genetic Analysis of the Relationship between the Browning Reaction and Bacterial Blight Resistance Gene Xa3 in Rice

The relationship between bacterial blight resistance gene Xa3 and browning reaction was genetically analyzed using F₂ plants from the cross of rice cultivar Kuntulan with Kinmaze. Kuntulan harbors resistance Xa3 and developes a browning reaction to avirulent races of Xanthomonas oryzae pv. oryzae, whereas Kinmaze has a typical susceptible reaction to all known Japanese races of X. o. pv. oryzae. The F₂ plants were tested for their resistance to avirulent race II strain of X. o. pv. oryzae and the development of browning. Of 337 F₂ plants tested, 251 had resistance to the strain. In all the resistant plants, a browning reaction developed around the point of inoculation. The remaining 86 had a susceptible reaction to the strain without a browning reaction. The F₂ population of Kuntulan × Kinmaze had a clear-cut segregation ratio of 3R : 1S. These facts led to the conclusion that the browning reaction is a pleiotropic effect of Xa3. Received 29 January 2001/ Accepted in revised form 24 April 2001     

Cell proliferation potency is independent of FGF4 signaling in trophoblast stem cells derived from androgenetic embryos

We previously established trophoblast stem cells from mouse androgenetic embryos (AGTS cells). In this study, to further characterize AGTS cells, we compared cell proliferation activity between trophoblast stem (TS) cells and AGTS cells under fibroblast growth factor 4 (FGF4) signaling. TS cells continued to proliferate and maintained mitotic cell division in the presence of FGF4. After FGF4 deprivation, the cell proliferation stopped, the rate of M-phase cells decreased, and trophoblast giant cells formed. In contrast, some of AGTS cells continued to proliferate, and the rate of M-phase cells did not decrease after FGF4 deprivation, although the other cells differentiated into giant cells. RO3306, an ATP competitor that selectively inhibits CDK1, inhibited the cell proliferation of both TS and AGTS cells. Under RO3306 treatment, cell death was induced in AGTS cells but not in TS cells. These results indicate that RO3306 caused TS cells to shift mitotic cell division to endoreduplication but that some of AGTS cells did not shift to endoreduplication and induced cell death. In conclusion, the paternal genome facilitated the proliferation of trophoblast cells without FGF4 signaling.     

Bacillus cereus from the environment is genetically related to the highly pathogenic B. cereus in Zambia

To follow-up anthrax in Zambia since the outbreak in 2011, we have collected samples from the environment and the carcasses of anthrax-suspected animals, and have tried to isolate Bacillus anthracis. In the process of identification of B. anthracis, we collected two isolates, of which colonies were similar to B. anthracis; however, from the results of identification using the molecular-based methods, two isolates were genetically related to the highly pathogenic B. cereus, of which clinical manifestation is severe and fatal (e.g., pneumonia). In this study, we showed the existence of bacteria suspected to be highly pathogenic B. cereus in Zambia, indicating the possibility of an outbreak caused by highly pathogenic B. cereus.     

Calf production from vitrified bovine sexed embryos following in‐straw dilution

The objective of this study was to develop an in‐straw dilution method suitable for direct transfer of vitrified bovine sexed embryos. Embryo sexing was performed by molecular diagnosis. Several sexed and vitrified‐warmed embryos were transferred after evaluation of morphologically embryonic survival at warming and in‐straw dilution (Evaluation group). The other embryos were immediately directly transferred to recipients without first being expelled from the straws after in‐straw dilution (Non‐evaluation group). The pregnancy rates of vitrified sexed embryos were 38.7% and 34.8% in the Evaluation group and Non‐evaluation group, respectively, which were not significantly different. The viability of lower quality embryos before vitrification tended to be lower (P = 0.087) than that of the higher quality embryos regardless of evaluating embryos after warming and in‐straw dilution. The abortion rates were similar, and there was no difference between the two groups (13.9% and 12.5%, respectively). These results demonstrate that vitrified bovine sexed embryos can be vitrified and diluted by the in‐straw method and that the vitrified and warmed sexed embryos can develop to term.