Abnormal clonalities of B-lymphocytes in bovine leukemia virus-infected cattle with persistent lymphocytosis

Peripheral B-lymphocyte clonality of 274 bovine leukemia virus-infected cattle with lymphocytosis was analyzed using clonality PCR based on sequences of the variable region of the bovine immunoglobulin H chain. None of the cattle showed monoclonal proliferation, while 10, 31, and 233 showed minor-clonal, oligoclonal, and polyclonal proliferation, respectively. A total of 163 cattle were analyzable the following year, and lymphocytosis was maintained in 157, indicating persistent lymphocytosis (PL). B-lymphocyte clonality of the 157 PL cattle was minor-clonal in 6 (3.8%), oligoclonal in 8 (5.1%), and polyclonal in 143 (91.1%). A higher rate of enzootic bovine leukosis (EBL) onset within a year was observed in PL cattle with minor-clonal (50.0% (3/6)) and oligoclonal (25.0% (2/8)) proliferation compared to those with polyclonal (5.6% (8/143)) proliferation. Minor-clonal and oligoclonal proliferation in PL cattle may be a prognosis factor for developing EBL.     

Suitability of Japanese codling as a raw material for surimi-based products revealed by primary sequence analysis of myosin heavy chain and thermal gel properties

Fisheries Science - Complementary DNA encoding a part of myosin heavy chain was cloned from fast skeletal muscle of Japanese codling Physiculus japonicus. Japanese codling, a frequent catch off the...     

Establishment of a model for chemoattraction of <Emphasis Type="Italic">Symbiodinium</Emphasis> and characterization of chemotactic compounds in <Emphasis Type="Italic">Acropora tenuis</Emphasis>

Corals harbor symbiotic dinoflagellates, Symbiodinium spp., acquired from surrounding environments. Because Symbiodinium are present at low densities in the water column, corals may attract these symbionts using chemotactic compounds. To examine whether corals contain chemotactic compounds, we established an assay to measure the chemotactic activity for Symbiodinium using an extract of the coral Acropora tenuis, a major reef-building coral in Japan. Our assay revealed that Symbiodinium strain NBRC102920 (clade A), which is taken up by juvenile A. tenuis polyps, is attracted to crude A. tenuis extracts. We found that the chemotactic compounds are water-soluble, heat-labile macromolecules and that the chemotactic activity was inhibited by N-acetyl-d-glucosamine (GlcNAc). We separated the GlcNAc-binding fraction (Fr-ActL) and identified it as the most plausible candidate for the chemoattractant, since the chemotactic activity of the crude A. tenuis extract appeared to be mainly attributable to the activity of Fr-ActL and was also inhibited by the addition of GlcNAc. These results indicate that chemoattraction is mediated via the binding of Symbiodinium to Fr-ActL.     

Reactivity of lignin with different composition of aromatic syringyl/guaiacyl structures and erythro/threo side chain structures in β-O-4 type during alkaline delignification: as a basis for the different degradability of hardwood and softwood lignin

The reactivity of lignin during alkaline delignification was quantitatively investigated focusing on the effect of the structural differences between syringyl and guaiacyl aromatic nuclei and between erythro and threo in the side chain of β-O-4 type lignin substructure on the β-O-4 bond cleavage rate. It was known that the ratio of this reaction rate of the erythro to threo isomers of the dimeric β-O-4 type lignin model compound with two guaiacyl aromatic nuclei was ca. 4. However, the presence of a syringyl nucleus strongly influenced the rate, and the ratio of the syringyl type analogue was in the range between 2.7 and 8.0 depending on the reaction temperature. The effect of syringyl nucleus on the enhancement of the reaction rate appeared to be greater when the syringyl nucleus consists of the cleaving ether bond rather than being a member of the carbon framework.     

Structure-based mechanistic insights into DNMT1-mediated maintenance DNA methylation

DNMT1, the major maintenance DNA methyltransferase in animals, helps to regulate gene expression, genome imprinting, and X-chromosome inactivation. We report on the crystal structure of a productive covalent mouse DNMT1(731-1602)-DNA complex containing a central hemimethylated CpG site. The methyl group of methylcytosine is positioned within a shallow hydrophobic concave surface, whereas the cytosine on the target strand is looped out and covalently anchored within the catalytic pocket. The DNA is distorted at the hemimethylated CpG step, with side chains from catalytic and recognition loops inserting through both grooves to fill an intercalation-type cavity associated with a dual base flip-out on partner strands. Structural and biochemical data establish how a combination of active and autoinhibitory mechanisms ensures the high fidelity of DNMT1-mediated maintenance DNA methylation.     

A plant peptide encoded by CLV3 identified by in situ MALDI-TOF MS analysis

The Arabidopsis CLAVATA3 (CLV3) gene encodes a stem cell-specific protein presumed to be a precursor of a secreted peptide hormone. Matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) applied to in situ Arabidopsis tissues determined the structure of a modified 12-amino acid peptide (MCLV3), which was derived from a conserved motif in the CLV3 sequence. Synthetic MCLV3 induced shoot and root meristem consumption as cells differentiated into other organs, displaying the typical phenotype of transgenic plants overexpressing CLV3. These results suggest that the functional peptide of CLV3 is MCLV3.     

Amino acid substitution at position 95 in rabies virus matrix protein affects viral pathogenicity

We previously reported that rabies virus strain CE(NiM), but not the parental Ni-CE strain, killed mice after intracerebral inoculation. CE(NiM) and Ni-CE are genetically identical except for two amino acids at positions 29 and 95 in the M protein. In this study, to identify which residue determines the pathogenicity, we examined pathogenicities of two Ni-CE mutants, CE(NiM29) and CE(NiM95), which were established by replacement of an amino acid residue at position 29 or 95 in the Ni-CE M protein with the corresponding residue of CE(NiM), respectively. We found that CE(NiM95), but not CE(NiM29), killed mice, indicating that the amino acid at position 95 in the M protein is the pathogenic determinant.     

In-straw cryoprotectant dilution for bovine embryos vitrified using Cryotop

The aim of this study was to develop an in-straw dilution method suitable for 1-step bovine embryo transfer of vitrified embryos using the Cryotop vitrification-straw dilution (CVSD) method. The development of embryos vitrified using the CVSD method was compared with those of embryos cryopreserved using in-straw vitrification-dilution (ISVD) and conventional slow freezing, outside dilution of straw (SFODS) methods. In Experiment 1, in vitro-produced (IVP) embryos cryopreserved using the CVSD method were diluted, warmed and exposed to the dilution solution at various times. When vitrified IVP embryos were exposed to the dilution solution for 30 min after warming, the rates of embryos developing to the hatched blastocyst stage after 72 h of culture (62.0-72.5%) were significantly lower (P<0.05) than those of embryos exposed to the solution for 5 and 10 min (82.4-94.3%), irrespective of supplementation with 0.3 M sucrose in the dilution solution. In Experiment 2, the rate of embryos developing to the hatching blastocyst stage after 48 h of culture in IVP embryos cryopreserved using the SFODS method (75.0%) was significantly (P<0.05) lower than those of embryos cryopreserved using the CVSD and ISVD methods (93.2 and 97.3%, respectively). In Experiment 3, when in vivo-produced embryos that had been cryopreserved using the CVSD, ISVD and SFODS methods and fresh embryos were transferred to recipient animals, no significant differences were observed in the conception and delivery rates among groups. In Experiment 4, when IVP embryos derived from oocytes collected by ovum pick-up that had been cryopreserved using the CVSD and ISVD methods and fresh embryos were transferred to recipient animals, no significant differences were observed in the conception rates among groups. Our results indicate that this simplified regimen of warming and diluting Cryotop-vitrified embryos may enable 1-step bovine embryo transfer without the requirement of a microscope or other laboratory equipment.     

Knowledge,attitudes, and practices (KAP) related to brucellosis and factors affecting knowledge sharing on animal diseases: a cross-sectional survey in the dry zone of Sri Lanka

Farmers’ lack of knowledge is assumed to have affected the presence of brucellosis in Sri Lanka for decades. This study, carried out in the Ampara district in the dry zone of Sri Lanka, revealed that there is a significant knowledge gap for brucellosis compared to foot and mouth disease (FMD) (p?<?0.001). Only 8.3% of farmers knew that brucellosis causes cattle abortions. Only 2.6% knew that it is zoonotic. The difference in knowledge of the symptoms and transmission of brucellosis and FMD was significant (p?<?0.001). Farmers’ attitudes and practices related to the spread of the disease were poor. Farmers’ education and spoken language had a negative influence on knowledge. Young people and those with strong social relationships were efficient in knowledge sharing. It can be concluded that brucellosis knowledge, attitudes, and practices are poor; thus, there is a need for more attention in disease control policymaking. Backward farmer groups should be the focus in animal health extension programs.     

Thermal stimulation at 39°C facilitates the fusion and elongation of C2C12 myoblasts

The aim of this study was to determine the effect of thermal stimulation at 39°C on the fusion and elongation of skeletal muscle cells. During a 5 day differentiation process of C2C12 cells, nine groups subjected to varying lengths of thermal stimulation at 39°C were established. Afterward, all groups were immunostained using anti‐muscle heavy‐chain antibody to test for myotube formation. Quantification of the myotube area demonstrated a significant increase in the group subjected to thermal stimulation at 39°C during the latter half of the differentiation compared with the control group, but the fusion index was significantly higher in the group that received hyperthermic treatment during the first half of the differentiation period. Moreover, the longitudinal length of myotubes was significantly increased in the groups that were subjected to thermal stimulation at 39°C during the latter half of the differentiation period. The distance between the center of myotubes and the nucleus farthest away from the center was substantially extended in the group receiving thermal stimulation at 39°C only on the fourth day of the differentiation. Together, these results demonstrate that thermal stimulation at 39°C facilitates myoblast fusion and elongation.