Reproductive characteristics of the feral raccoon (Procyon lotor) in Hokkaido,Japan

Reproduction of feral raccoons (Procyon lotor) in Hokkaido, Japan, was examined during a 2-year period by analysis of placental scars or fetuses in the uterus. Of 242 collected females, 69 (29%) were juveniles, 71 (29%) yearlings, and 102 (42%) adults. The pregnancy rate averaged 66% in yearlings and was significantly lower than the 96% average observed in adults (p<0.01). Litter size ranged from 1 to 7 offspring per female, and averaged 3.6 in yearlings and 3.9 in adults. There was no significant difference in mean litter size between yearlings and adults. In Hokkaido, the raccoon mating season peaked in February and the majority of litters were born between March and May, similar to patterns described in North America, but some females mated in summer. The reproductive potential of feral raccoons in Hokkaido was similar to that reported in North America. The recent increase in raccoon numbers can be explained by their high productivity. Harvest data suggest that hunting pressure on juveniles is lower than that for older age classes when using box traps in summer. In order to reduce the feral raccoon population, alternative hunting methods that increase juvenile mortality rates are needed.     

Effect of adenosine infusion on isoflurane MAC in dogs.

Adenosine is a potent analgesic in people and reduces the MAC of halothane in dogs. The purpose of this study was to determine whether adenosine reduces the MAC of isoflurane in dogs. Seven beagles (four males and three females) were anesthetized and randomly assigned to receive adenosine (0.3 mg kg^–1 minute^–1; 6 mL kg^–1 hour^–1, IV) or saline (0.9%, 6 mL kg^–1 hour^–1IV). After an interval of ≥7 days, each dog was reanesthetized and treated with the alternate infusion. Anesthesia was induced and maintained with isoflurane in oxygen. Dogs were intubated and instrumented for measurement of mean systemic arterial blood pressure and airway concentration of isoflurane and end‐tidal partial pressure of carbon dioxide. The MAC for isoflurane was determined using the tail‐clamp technique. Baseline MAC values were 1.25 (1.15, 1.35)% [median (minimum, maximum)] and 1.25 (1.05, 1.45)% before the saline and adenosine treatments, respectively. After 2 hours of infusion with saline or adenosine, MAC values were not different (p = 0.156) and were 1.25 (0.95, 1.35)% and 1.05 (1.00, 1.25)%, respectively. Two hours following the end of each infusion, the MAC values for saline and adenosine treatment groups differed significantly (p = 0.015), but by no more than the normal variation inherent in this study, and were 1.15 (1.15, 1.35)% and 1.05 (1.05, 1.25)%, respectively. Mean arterial blood pressure was 93 (74, 123) mm Hg for saline treated dogs and 67 (52, 72) mm Hg (p = 0.008) during adenosine infusion. End‐tidal carbon dioxide was not different between the two treatment groups. We conclude that adenosine administered at 0.3 mg kg^–1 minute^–1had no effect on isoflurane MAC in dogs, but decreased mean arterial blood pressure.     

Kinetics of endotoxin concentration and tumor necrosis factor-alpha,interleukin-1beta,and interleukin-6 activities in the systemic and portal circulation during small intestinal ischemia and reperfusion in dogs

OBJECTIVE: To determine whether small intestinal ischemia and reperfusion induces bacterial translocation and proinflammatory cytokine response in either the systemic or portal circulation in dogs. ANIMALS: 17 healthy adult Beagles. PROCEDURE: The superior mesenteric artery (SMA) was occluded for 0 (group-3 dogs), 30 (group-1 dogs), or 60 (group-2 dogs) minutes, followed by reperfusion for 180 minutes; serum lactate and endotoxin concentrations and tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and IL-6 activities in the systemic and portal circulation and intramucosal pH were measured at various time points. RESULTS: In group-2 dogs, TNFalpha activity was found to be significantly increased in the portal circulation, peaking at 60 minutes of reperfusion; TNF-alpha activity, in the systemic circulation, gradually increased from 60 minutes of reperfusion to the end of the experiment; however, the increase was not significant. In group-1 and -2 dogs, IL-6 activities significantly and gradually increased in the systemic and portal circulation during the reperfusion phase, and the magnitude of these increases was dependent on the duration of the ischemic phase. There were no significant changes in IL-1beta activity or endotoxin concentration in any dog group. CONCLUSIONS AND CLINICAL RELEVANCE: Results of the our study indicate that intestinal ischemia and reperfusion leads to significant increases of the circulating TNF-alpha and IL-6 activities, depending on the duration of the ischemia phase, in the absence of detectable endotoxin in the circulation. This finding suggests that intestinal ischemia and reperfusion induces a systemic proinflammatory cytokine response in dogs.     

Effects of LH and PGF2alpha in equine dominant follicles observed by MDS

Microdialysis System (MDS) is a novel technique used for investigation of molecule secretion between different cell populations. Local hormonal secretion at follicular wall has been still unclear. This MDS study was used to determine progesterone (P4), androstenedione (A4), estradiol-17beta (E2) and Prostaglandin F2alpha (PGF2alpha) release in mare pre-ovulatory follicles. Follicles larger than 30 mm were isolated from the ovary and follicular fluid aspirated for hormone assay. Follicular fluid collected from small, middle and large follicles were analyzed by EIA. The concentrations of P4 and PGF2alpha were similar among the different sizes of follicles. The release of A4 was observed in middle and large follicles. E2 concentration was observed in middle follicles and was higher in large follicles compared with middle follicles. Follicular wall was cut and incubated for MDS and when LH was infused, there was an increase in P4 and A4 release. PGF2alpha release was considerably high after LH infusion compared to the control group. Infusion of PGF2alpha increased P4 and A4 release but there was no change in E2 release. This results suggest that in pre-ovulatory follicles, LH stimulates theca interna cells and also PGF2alpha seemed to have a mediator role to induce steroid hormone production and luteinization of follicular cells. The nature of the mechanisms involved in selection of large follicles is still a perplexing research problem in reproduction.     

Molecular cloning and characterization of chicken tumor necrosis factor (TNF)-superfamily ligands, CD30L and TNF-related apoptosis inducing ligand (TRAIL)

CD30 ligand (CD30L) and tumor necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL) are members of the TNF-superfamily that have many important biological activities in cell proliferation and apoptotic death. In this study, both genes in the chicken were cloned and their expression was analyzed. Complementary DNA fragments were obtained from a suppressive subtractive hybridization library with or without lipopolysaccharide (LPS)-stimulation. Chicken CD30L consists of 1,152 base pairs (bp) with an open reading frame (ORF) of 720 bp having 36.4% identity with human CD30L, whereas chicken TRAIL is 1,134 bp long with an ORF of 912 bp having 54.4% identity with human TRAIL. Chicken CD30L was expressed at high levels in the spleen, bursa of Fabricius and in the chicken monocytic leukemia cell line, IN24. Stimulation with LPS in the spleen, bursa of Fabricius and the IN24 cell line did not affect CD30L expression. The gene expression of chicken TRAIL was essentially to the same level in all tissues examined. The time course of expression was not significantly altered by LPS-stimulation in the spleen, thymus and bursa of Fabricius, but reached a maximal level 8 hr after stimulation in the IN24 cell line. The high level expression of both genes in lymphoid organs and IN24 cell line indicates that chicken CD30L and TRAIL may also play an important role in apoptotic signal transduction and the regulation of cell proliferation in the immune system.     

Anisotropic thermal properties of molded carbon phenolic spheres

Anisotropic thermal properties of molded carbon phenolic spheres (CPS), a mixture of sugi wood charcoal powders and phenol formaldehyde resin molded with a hot press, were investigated. The effects of the carbonizing temperature, particle size of chars, and density of the CPS on thermal properties were discussed. The molded CPS specimens were measured for their thermal properties using the laser flash method in both horizontal and vertical directions. The configuration of the CPS was observed by scanning electron microscopy. Anisotropy of the thermal properties (thermal diffusivity and thermal conductivity) between horizontal and vertical directions of the molded CPS was much higher than that of the uncarbonized molded phenolic spheres. Therefore, converting wood into molded CPS is an effective way to enhance the thermal-anisotropy properties. More marked effects of the carbonizing temperature, particle size, and density were observed in the horizontal direction than in the vertical direction. Anisotropy in thermal properties of the molded CPS may be considered an advantage for developing a new fire-retardant material for wood composites.An outline of this study was presented at the 47^th and 48^th annual meetings of the Japan Wood Research Society, Kochi and Shizuoka, 1997 and 1998.     

Molecular basis of the shish-kebab morphology in polymer crystallization

In the rich and long-standing literature on the flow-induced formation of oriented precursors to polymer crystallization, it is often asserted that the longest, most extended chains are the dominant molecular species in the "shish" of the "shish-kebab" formation. We performed a critical examination of this widely held view, using deuterium labeling to distinguish different chain lengths within an overall distribution. Small-angle neutron-scattering patterns of the differently labeled materials showed that long chains are not overrepresented in the shish relative to their concentration in the material as a whole. We observed that the longest chains play a catalytic role, recruiting other chains adjacent to them into formation of the shish.     

The 2011 Tohoku-Oki earthquake: displacement reaching the trench axis

We detected and measured coseismic displacement caused by the 11 March 2011 Tohoku-Oki earthquake [moment magnitude (M(W)) 9.0] by using multibeam bathymetric surveys. The difference between bathymetric data acquired before and after the earthquake revealed that the displacement extended out to the axis of the Japan Trench, suggesting that the fault rupture reached the trench axis. The sea floor on the outermost landward area moved about 50 meters horizontally east-southeast and ~10 meters upward. The large horizontal displacement lifted the sea floor by up to 16 meters on the landward slope in addition to the vertical displacement.