Mobility of the forearm skeleton in the Asiatic black (Ursus thibetanus), brown (U. arctos) and polar (U. maritimus) bears

In several primates and carnivores, pronation/supination angles of the forearm skeleton were examined, and it is thought that a larger angle is useful to acquire dexterous behaviors in feeding and/or life style, including climbing. In this study, the pronation/supination angles in Asiatic black, brown and polar bears were nondestructively examined. These specimens were classified as adult or non-adult. Three or four carcasses of each group of Asiatic black and brown bears were used for CT analysis, whereas only one adult polar bear was used. The forearms were positioned within the gantry of a CT scanner in both maximally supinated and pronated states. Extracted cross-sectional CT images of two positions were superimposed by overlapping the outlines of each ulna. The centroids of the radii were detected, and then the centroid of each radius and the midpoint of a line which connects between both ends of the surface of each radius facing the ulna, were connected by lines to measure the angle of rotation as an index of pronation/supination. In adult brown and polar bears, the angles were smaller as compared with the other groups (Asiatic black and non-adult brown bears). Asiatic black and non-adult brown bears can climb trees, whereas adult brown bears and polar bears cannot. This suggests that the pronation/supination angle is related to arboreal activity in Ursidae.     

Time‐coordinated prevalence of extracellular HGF,FGF2 and TGF‐β3 in crush‐injured skeletal muscle

Successful regeneration and remodeling of neuromuscular junctions are critical for restoring functional capacities and properties of skeletal muscle after damage, and axon‐guidance molecules may be involved in the signaling that regulates such restoration. Recently, we found that early‐differentiated satellite cells up‐regulate a secreted neural chemorepellent Sema3A upon in vivo muscle‐crush injury. The study also revealed that Sema3A expression is up‐regulated in primary satellite‐cell cultures in response to hepatocyte growth factor (HGF) and basic fibroblast growth factor (FGF2) and is prevented by transforming growth factor (TGF)‐β2, 3. In order to verify the physiological significance of this regulation in vitro, the present study was designed to estimate the time‐course of extracellular HGF, FGF2 and TGF‐β3 concentrations after crush‐injury of Gastrocnemius muscle in the rat lower hind‐limb, using a combination of a non‐homogenization/non‐spin extraction of extracellular wound fluids and enhanced chemiluminescence–Western blotting analyses. Results clearly demonstrated that active HGF and FGF2 are prevalent in 2–8 days post‐crush, whereas active TGF‐β3 increases after 12 days, providing a better understanding of the time‐coordinated levels of HGF, FGF2 and TGF‐β3 that drive regulation of Sema3A expression during regenerative intramuscular moto‐neuritogenesis.     

Effect of estrus synchronization treatment after luteolysis on Holstein heifers as embryo transfer recipients

This study was designed to evaluate the effect of estrus synchronization treatments on recipient heifers for embryo transfer (ET). Holstein heifers were separated into the following three groups: (i) an administration of 50 µg GnRH (gonadotropin‐releasing hormone) analog was given to heifers at a random stage of the estrus cycle, followed 7 days later by two administrations of 7.5 mg prostaglandin F2 alfa analog (PG) as control; (ii) another administration of 100 µg GnRH was given to the control group at 48 h after the administration of PG as the second GnRH group; and (iii) an administration of 0.75 mg estradiol benzoate (E2) was given to the control group at 24 h after the administration of PG as the E2 group. Each method caused estrus synchronization. Fresh embryos were nonsurgically transferred into the suitable recipients that had a functional corpora lutea (CL) 7 days after estrus. The E2 group showed a significantly higher (P < 0.01) rate of estrus synchronization (98.9%) at 1–3 days after PG administration and the final pregnancy rate of the E2 group (50.6%) was also significantly higher than the other groups (37.1%, P < 0.05 and 30.9%, P < 0.01, respectively). These findings demonstrate that E2 administration 24 h after PG protocol is effective for estrus synchronization of Holstein heifers, thus improving the productivity of ET.     

Expression analysis of an α‐1, 3‐galactosyltransferase,an enzyme that creates xenotransplantation‐related α–Gal epitope,in pig preimplantation embryos

α‐1,3‐Galactosyltransferase (α‐GalT), an enzyme creating Galα1‐3Gal (α‐Gal) epitope on the cell surface in some mammalian species such as pigs, is known to be a key factor that causes hyperacute rejection upon transplantation from pigs to humans. To establish the RNA interference‐based suppression of endogenous α‐GalT messenger RNA (mRNA) synthesis in porcine preimplantation embryos, we determined the suitable embryonic stage at which stage such approach is possible by using the semi‐quantitative RT‐PCR (qRT‐PCR) and the cytochemical method using a fluorescence‐labeled Bandeiraea simplicifolia Isolectin B₄ (BS‐I‐B₄). Staining with BS‐I‐B₄ demonstrated that α‐Gal epitope expression was first recognized at the 8‐cell stage, and increased up to the hatched blastocyst stage. Single embryo‐based qRT‐PCR also confirmed this pattern. These results indicate that creation of α‐Gal epitope is proceeded by de novo synthesis of α‐GalT mRNA in porcine preimplantation embryos with peaking at the blastocyst stage.     

Survey of major capsid genes (g23) of T4-type bacteriophages in Japanese paddy field soils

Many studies have shown the ecological importance of viruses as the greatest genomic reservoirs on the planet. As bacteriophages (phages) comprise the majority of viruses in the environment, we surveyed the capsid genes (g23) of T4-type phages, Myoviridae, from DNA extracts of three paddy field soils located in northern, central and southern Japan using the degenerate primers MZIA1bis and MZIA6. Denaturing gradient gel electrophoresis (DGGE) was performed to separate PCR-amplified g23 products, and 56 DGGE bands were identified as g23 fragments. Only nine clones were grouped into T-evens, PseudoT-evens and ExoT-evens, and most of the other clones were classified into Paddy Groups I-VI. No significantly different distribution of g23 clones was observed among the paddy fields at the group level, indicating that phage communities estimated from the g23 composition were common on the nationwide level. Comparison of g23 sequences showed that g23 genes in paddy fields were different from those in marine environments, and more divergence of g23 genes was estimated in the paddy fields compared to the marine environment. Two novel g23 clones with very short amino acid residues were detected, suggesting the existence of uncharacterized, novel groups of g23 genes in paddy field soils.     

Evaluation of strength distribution at cut slope of decomposed granite with the use of sounding method and geophysical exploration method

Paddy and Water Environment - Natural slopes and cut slopes frequently collapse due to heavy rain and earthquakes, causing disasters. Countermeasures must be applied to mitigate such disasters....     

Genetic analysis of shiga-toxigenic Escherichia coli isolates from cattle in a limited region

The ecology of shiga‐toxigenic Escherichia coli (STEC) is important in the animal production environment. We investigated fecal shedding of STEC in one town in Miyagi, Japan by multiplex polymerase chain reaction (PCR) targeting shiga toxin gene 1 (stx₁), gene 2 (stx₂) and malB promoter gene, and analyzed the PCR products of stx₁ or stx₂ (54 samples) by direct sequencing. Three of 46 (6.5%) beef cattle in the University Farm of Tohoku University (Kawatabi Farm) and 11 of 70 (15.7%) calves in neighboring dairy farms carried STEC. Rate of detecting genes of stx₁, stx₂ and stx₁₊₂ was 3.4% (4/116), 8.6% (10/116) and 0.9% (1/116), respectively. Serotyping indicated that STEC contaminated farms at different times or through different routes. Isolates harbored no mutation among stx₁, but six (Kawatabi Farm) and 38 (neighboring farms) base substitutions among stx₂, respectively. The diversity of substitutions of stx₂ was observed among farms or even in a farm. Phylogenic analysis revealed that STEC detected in the area were classified into three clusters by the variety of stx₂. Sequence analysis of stx₂ will be one of the tools for clarifying the source of outbreaks and the route of contamination of STEC.     

Initiatives and behavioral sequence of maternal behavior in Japanese Black and Japanese Shorthorn cattle (Bos taurus)

Maternal grooming (MG), nursing (NS) and mother‐infant behavior 5 min before (IB5) and immediately before (LIB) maternal behavior were observed in Japanese Black (JB) and Japanese Shorthorn (JS) cow‐calf pairs. During MG of the JB, the number of calf's IB5 was more than that of cows, but the duration of the MG positively correlated with the number of cow's IB5. During MG of the JS, the duration positively correlated with the number of calf's IB5. The number of the NS with calf's LIB and the number of calf's IB5 in the NS were more than those of cows in both breeds. The duration of the NS tended to correlate with the number of calf's IB5 in the JS. Main behavior sequence was observed like cow's approach, MG, calf's contact and NS, in this order, in both breeds. It is thought that the MG is released by cow's and calf's activities in both breeds and accelerated by the cow's activeness in the JB and by the calf's activeness in the JS, and that the NS is released and accelerated by the calf's activeness in JS.