The regulation of food intake and correlated energy balance in mice.

In order to study the regulation of food intake and correlated body energy metabolism, the effect of restricted feeding during the light period in female IVCS mice was investigated. Access to food and water was restricted (RF group) for 3 weeks only from 10:00 hr to 17:00 hr, and that in the control group remained ad libitum. After starting food restriction (day 1), mean food intake decreased to 10% of the control value, then rose sharply, over the next 3 days, to reach 70% of the control value. Then, it decreased gradually to about 50% of the control value and remained at this low level thereafter. There was no significant difference between mean body weights for the two groups. Feed-efficiency was considered, therefore, to be higher in the RF than in the control group. RF-treatment increased plasma corticosterone levels and decreased locomotor activity. However, the diurnal patterns of plasma corticosterone levels and locomotor activity observed suggest that the circadian rhythm, synchronized with the light-dark cycle, persisted during RF-treatment. These findings suggest that restricted feeding during the naturally inactive phase (light period) induces a decrease in food intake. Animals seem to adapt to underfeeding, at least partly, by increasing feed-efficiency and plasma corticosterone levels and decreasing locomotor activity.     

Parental chromosome differentiation in citrangequat [Fortunella sp. × (Citrus sinensis × Poncirus trifoliata)] using CMA banding patterns

The efficiency of chromomycin A₃ (CMA) staining was examined for parental chromosome differentiation in citrange [Citrus sinensis (L.) Osbeck × Poncirus trifoliata (L.) Raf.] and citrangequat (Fortunella sp. × citrange). All of the accessions analyzed had the same chromosome number of 2n = 18. CMA staining revealed six characteristic banding patterns on the basis of the number and position of CMA positive bands (CMA⁺) as follows; A: two terminal and one proximal band, B: one terminal and one proximal band, C: two terminal bands, D: one terminal band, E: no band, and F: one proximal band. Chromosome CMA banding patterns of the accessions were 1A + 1B + 2C + 13D + 1F in Fortunella margarita, 2B + 2C + 7D + 7E in ‘Fukuhara’ orange, 2B + 10D + 6E in Poncirus trifoliata, 1B + 1C + 10D + 6E in citrange and 1A + 1C + 11D + 4E + 1F in citrangequat. The results of this study confirmed the intergeneric and tri-generic hybridity of citrange and citrangequat, respectively.     

A case of canine primitive neuroectodermal tumor (PNET)

A 2-year and 6 month-old, female, Golden Retriever showed circling behavior and seizure. By magnetic resonance imaging (MRI) examination, a mass was found on the surface of the left cerebral hemisphere, invading to the left temporal muscle. The skull bone between them was destroyed. The dog was euthanized and necropsied. Histologically, the mass contained a lot of undifferentiated anaplastic cells, forming Homer-Wright rosettes and pseudopalisading patterns. Thus, the case was diagnosed as primitive neuroectodermal tumor (PNET).     

Quantitative diversity of 67 kda protective antigen among serovar 2 strains of Erysipelothrix rhusiopathiae and its implication in protective immune response

Mouse monoclonal antibodies (MAbs), raised against the NaOH-extracted antigen of Erysipelothrix rhusiopathiae strain Kyoto (serovar 2), recognized two different epitopes on a single protein of molecular weight 67 kDa. The MAbs were classified as protective or non-protective against strain Fujisawa (serovar 1). In immunoblotting analysis using the MAbs, fifteen wild strains were shown to contain different amounts of 67 kDa protective antigen. Each formalin-killed whole cell vaccine (bacterin) prepared from the fifteen wild strains conferred different levels of protection against strain Fujisawa in mice. Bacterins prepared from wild strains with larger amounts of 67 kDa protective antigen tended to give high levels of antigen-specific antibody and better protection to mice. These results indicate that the amount of 67 kDa protective antigen which influences the induction of protective immune responses may vary substantially among the strains of E. rhusiopathiae (serovar 2).     

Genetic selection for resistance to mycoplasmal pneumonia of swine (MPS) in the Landrace line influences the expression of soluble factors in blood after MPS vaccine sensitization

We recently developed a Landrace line that is resistant to mycoplasmal pneumonia of swine (MPS) infection by genetic selection for five generations, and we reported that the immunophenotype of this line is different from that of the non‐selected line in terms of changes in peripheral blood leukocyte population after MPS vaccination. This study followed up previous findings demonstrating changes in soluble factors in blood, namely, hormones, Mycoplasma hyopneumoniae‐specific immunoglobulin G (IgG), and cytokines. These two lines were injected with MPS vaccine on days ?7 and 0 after blood sampling on those days, and blood samples were collected on days ?14, ?7, 0, 2, 7 and 14. We found changes in the levels of many hormones and cytokines in both lines. However, we found that only growth hormone (GH) and interferon (IFN)‐γ levels were statistically different between these two lines. GH concentration was reduced (day 0) and IFN‐γ concentration was increased (day 14) in the MPS‐selected line compared with the non‐selected line, despite unchanged IFN‐γ messenger RNA expression in blood cells. Although detailed mechanisms underlying these phenotypes remain unsolved, these traits would be useful to improve MPS resistance in pig production and provide an insight into MPS infection.     

Macroscopic separation of dense fluid phase and liquid phase of phosphorus

Structural transformation between a dense molecular fluid and a polymeric liquid of phosphorus that occurred at about 1 gigapascal and 1000 degrees C was investigated by in situ x-ray radiography. When the low-pressure fluid was compressed, dark and round objects appeared in the radiograph. X-ray diffraction measurements confirmed that these objects were the highpressure liquid. The drops grew and eventually filled the sample space. Decompressing caused the reverse process. The macroscopic phase separation supported the existence of a first-order phase transition between two stable disordered phases besides the liquid-gas transition. X-ray absorption measurements revealed that the change in density at the transition corresponds to about 40% of the density of the high-pressure liquid.     

Pear (Pyrus Species) Genetic Resources in Iwate, Japan

Iwateyamanashi (Pyrus ussuriensis Maxim. var. aromatica (Nakai et Kikuchi) Rehd.) is one of the Pyrus species grown wild in Japan. The origin of the Japanese pear (P. pyrifolia) is uncertain but it has been suggested that Iwateyamanashi is the possible progenitor of the modern Japanese cultivar. During the last few decades, the number of Iwateyamanashi trees has been decreasing and therefore, conservation is urgently needed. After 13 explorations in the northern Tohoku region of Japan, 615 pear trees and 30 local names were recognized mainly in Iwate Prefecture. The center of the distribution seemed to be somewhere around Mt. Hayachine to the northern area of Kitakami highlands (from lat. 39 °20′ to 40 °10′N, and from long. 141 °20′ to 141 °50′E). Four morphological characters concerning fruit shape, measured for 85 trees, showed a wide range of continuous variation. For the skin colour of fruit, 51% of trees bore russet type fruits, 22% smooth and 27% intermediate ones. Most of the fruits had five loculi but Sanenashi fruits (seedless pear), one of the old cultivars, had three, and fruits of another two trees had four. More than 80% of trees tended to produce fruits with a calyx but some trees bore fruits without a calyx. These observations indicate a wide range of genetic diversity in Pyrus species which is caused, not only by high heterogeneity in Iwateyamanashi itself, but also by the coexistence of Iwateyamanashi, P. pyrifolia (Burm.) Nakai and hybrid progeny in this area. Already 250 trees have been conserved as genetic resources by grafting at Kobe University.