Chromosome doubling of Lychnis spp. by in vitro spindle toxin treatment of nodal segments

Lychnis (Caryophyllaceae) consists of about 30 species distributed throughout the temperate regions of the Northern Hemisphere, from East Asia to Europe. Many Lychnis spp. have high ornamental value and cultivated as pot or garden plants. In the present study, in vitro chromosome doubling of several Lychnis spp. was examined in order to widen their variability in horticultural traits. Initially effect of various spindle toxin treatments [100, 500 or 1000 mg l⁻¹ colchicine (COL), 10, 20 or 50 mg l⁻¹ oryzalin (ORY), or 1, 5, 10 mg l⁻¹ amiprophos-methyl (APM)] of nodal segments of a triploid genotype of L. senno (3x) was investigated on survival of nodal segments and chromosome doubling in nodal segment-derived plantlets. Significantly higher percentage (75.0%) of surviving segments after spindle toxin treatment was obtained in 10 mg l⁻¹ ORY treatment. Flow cytometry (FCM) analysis of leaf tissues showed that 9.4–13.8% of plantlets, which were derived from 10 to 20 mg l⁻¹ ORY, or 5 mg l⁻¹ APM treatments, were hexaploid (6x) or ploidy chimera (3x + 6x, 4x + 6x, 5x + 6x, 3x + 4x + 6x). The results obtained by FCM analysis were confirmed by chromosome observation in root tip cells. Thus 10 mg l⁻¹ ORY treatment of nodal segments is suitable for in vitro chromosome doubling of triploid L. senno. Efficient chromosome doubling was also achieved in diploid L. fulgens (2x) and L. sieboldii (2x) by treating nodal segments with 10 mg l⁻¹ ORY: 68.9–88.7% of nodal segments survived after ORY treatment, and 24.7–26.5% of plantlets derived from ORY-treated nodal segments were tetraploid (4x) or ploidy chimera (2x + 4x) in both species. These results indicate that the in vitro chromosome doubling method established for triploid L. senno may be applicable to a wide range of Lychnis spp. Tetraploid L. fulgens and L. sieboldii showed a compact plant form, and had thick stems and deep green leaves compared with the diploid mother plants. On the other hand, hexaploid L. senno showed very poor growth and died before flowering.     

Molecular cloning and tissue distribution of uncoupling protein 1 (UCP1) in plateau pika (Ochotona dauurica)

Uncoupling protein 1 (UCP1) is present exclusively in brown adipose tissue, and contributes to body temperature control during cold exposure. We cloned UCP1 cDNA of plateau pika (Ochotona dauurica), a small, non-hibernating, diurnal lagomorph that inhabits in relatively cold climates and at high altitudes in Mongolia and in northern China. The nucleotide sequence of pika UCP1 was highly homologous to UCP1 of other species, and the deduced amino acid sequence had some common domains for UCP, including six mitochondrial carrier protein motifs and a putative purine-nucleotide binding site. RT-PCR and Western blot analyses revealed that both UCP1 mRNA and protein were expressed exclusively in the interscapular adipose tissue. These results suggest that pika UCP1 contributes to heat production in brown adipose tissue, as do those in other species.     

Differential cytokine gene expression in CD4+ and CD8+ T cell subsets of calves

The distinct patterns of cytokine expression in CD4+ and CD8+ T cells are well understood in mice and humans. However, little information is available about cytokine expression in bovine CD4+ and CD8+ T cells. In this study, mRNA expression of 19 different cytokines was analyzed in CD4+ and CD8+ T cells of calves with or without Concanavalin A (Con A) stimulation. CD4+ and CD8+ T cell populations were enriched to 98% purity by positive selection using magnetic cell sorting (MACS). CD4+ T cells spontaneously expressed the mRNAs of interleukin-1alpha (IL-1alpha), IL-1beta, IL-2, IL-6, IL-7, IL-8, IL-10, IL-18, IFN-gamma, TNF-alpha, TNF-beta and TGF-beta, and augmented the mRNA expression of IL-10, IFN-gamma and TNF-beta after Con A stimulation. The mRNAs of IL-3, IL-4, IL-5, IL-13 and GM-CSF were newly expressed in Con A-stimulated CD4+ T cells. CD8+ T cells displayed spontaneous mRNA expression of IL-6, IL-18, TNF-alpha, TNF-beta and TGF-beta, and newly expressed the mRNA of IL-2, IL-7, interferon-gamma (IFN-gamma) and GM-CSF after Con A stimulation. It was found that CD4+ T cells expressed the mRNA of 17 cytokines except for IL-12 and IL-15, while CD8+ T cells expressed only the mRNA of 9 cytokines after Con A stimulation. The profile of cytokine mRNA expression was substantially different in the CD4+ and CD8+ T cells of calves, indicating that CD4+ T cells can be distinguished from CD8+ T cells by the cytokine gene expression of IL-1alpha, IL-1beta, IL-3, IL-4, IL-5, IL-8, IL-10 and IL-13. Differential cytokine expression between CD4+ and CD8+ T cells serve to interpret an individual function of T cell subsets in the immune system of calves.     

Staining patterns for actin and villin distinguish M cells in bovine follicle-associated epithelium

M cells play a central role in the initiation of mucosal immune responses. However, a primary source of difficulty for investigations of this is the lack of an available specific marker for bovine M cells. As M cells possess irregular and short microvilli, we investigated the distribution and localization of the microvillar proteins actin and villin by immunohistochemistry of the gut of calves. In ileum of the calf, actin and villin were clearly and continuously immunostained in the brush border of the villous epithelia, however, discontinuous immunostaining with patches of no staining were observed in follicle-associated epithelium (FAE). Electron microscopy revealed that M cells had irregular microvilli and lacked the typical brush border, and it was inferred that these patches of no staining might be the intercellular crevices of M cells. As the microvilli of M cells were very sparse, there were several areas of weak immunostaining in calf jejunal FAE. These results suggest that M cells in calf FAE are detectable by the absence of staining for actin and villin.     

Effects of Feeding Potato Pulp on Cholesterol Metabolism and Its Association with Cecal Conditions in Rats

To clarify the functional properties of potato pulp (PP), a waste product resulting from extraction of starch from potatoes, we examined the effects of PP on cholesterol metabolism and cecal conditions in rats. Plasma total cholesterol (T-Chol) levels were lower in rats fed a PP-supplemented diet for four weeks than in those fed a control diet. Cecal pH was lowered due to an increase in the levels of cecal total short-chain fatty acids, especially butyrate, in the PP group compared to the control group. Furthermore, animals fed with the PP-supplemented diet showed increased cecal ratios of Lactobacillus and Clostridia and decreased cecal ratios of Bacteroides and Gammaproteobacteria with slightly negative and positive correlations with plasma T-Chol levels, respectively. In conclusion, ingestion of PP for four weeks is likely to improve both cecal conditions and cholesterol metabolism, suggesting that PP has prebiotic effects.     

Nitrogen isotope fractionation during nitrogen transport from ectomycorrhizal fungi,Suillus granulatus,to the host plant,Pinus densiflora

The ¹⁵N natural abundance in Pinus densiflora Sieb. et Zucco that had been inoculated and not inoculated with ectomycorrhizal fungi (Suillus granulatus (L.:Fr.) O. Kuntze) was compared. The inoculated pine needles showed a lower δ¹⁵N value, while the uninoculated ones showed a higher δ¹⁵N value. Higher δ¹⁵N values in the mycelial mat of the ectomycorrhizal fungi compared to those of the inoculated pine needles were also observed. These facts indicate that nitrogen isotope fractionation occurred during the nitrogen transport from mycorrhizal fungi to the host plants.     

Effect of nitrogen deposition on CH4 uptake in forest soils in Hokkaido,Japan

Abstract

It has been well documented by short-term artificial experiments that the CH⁴ uptake is inhibited by N input, especially NH^{4 p+}-N input. To investigate the effect of the natural N input by throughfall and other factors on the CH⁴ uptake in forest soils, we measured the CH⁴ uptake rates for 6 months during the snow-free period of the year and N input by throughfall throughout the year at 10 sites in Hokkaido, Japan, from 1997 to 2002. Water filled pore space (WFPS) and pH values in the soils varied widely among the sites (38-93% and 3.9-6.2, respectively). The rates of NH^{4 p+}-N and NH^{3 p-}-N inputs ranged from 1.3 to 6.9 kg N ha^p-1 year^p-1 and from 0.8 to 2.9 kg N ha^p-1 year^p-1, respectively. The NH^{4 p+}-N input was generally higher than the NH^{3 p-}-N input. Total N input by throughfall amounted to 2.3-9.4 kg N ha^p-1 year^p-1. The highest CH⁴ uptake rate occurred within the period from July to September (41-215 μg CH⁴ m^p-2 h^p-1) each year at most sites. CH⁴ uptake rate was relatively low (~50 μg CH⁴ M-2 h^p-1) at northern sites, while a high CH⁴ uptake rate was observed throughout the year 100 (? CH⁴ m^p-2 h^p-1) at southern sites. The mean CH⁴ uptake rates were significantly different among the sites. Cumulative CH⁴ uptake ranged from 1.4 to 6.6 kg CH⁴ ha^p-1 [184 d]^p-1 with a mean values of 3.22 ± 1.36 kg CH⁴ ha^p-1 [184 d]^p-1. Cumulative CH⁴ uptake increased with increasing temperature and decreased with an increase in precipitation (Rain), NH^{4 p+}-N input (TF^NH4) WFPS, soil total C (TC), and total N (TN). There was a quadratic relationship between the CH⁴ uptake and NH^{3 p-}-N input (TF^NO3), soil pH, and C / N ratio in soil. A regression equation was obtained as follows to predict the CH⁴ uptake in forest soils: Cumulative CH⁴ uptake = 0.47 / Rain + 0.38 / TF^NH4 + 0.34 / TC - 0.30 / TF^N03 (R ^p2 = 0.74, p = 0.0001). This equation indicates that atmospheric N input into forest soils is one of the main factors that control cumulative CH⁴ uptake with precipitation, total carbon content in soil in Hokkaido, Japan.     

Clinical assessment of systolic myocardial deformations in dogs with chronic mitral valve insufficiency using two-dimensional speckle-tracking echocardiography

ObjectiveThe objective of this study was to clinically assess myocardial deformations in dogs with chronic mitral valve insufficiency (CMVI) using two-dimensional speckle-tracking echocardiography (2D-STE).Animals87 dogs with CMVI.MethodsDogs were placed into 1 of 3 classes, based on the International Small Animal Cardiac Health Council classification. In addition, 20 weight- and age-matched healthy dogs were enrolled as controls. The dogs were examined for myocardial deformations using 2D-STE, and strain and strain rate in the longitudinal, circumferential, and radial directions were evaluated.ResultsClass II and III dogs had higher circumferential strain than class I dogs (P = 0.002 and P = 0.001, respectively) and controls (P < 0.001 and P < 0.001, respectively). Class III dogs had higher radial strain than class I dogs (P = 0.001) and controls (P < 0.001). Class III dogs had higher radial strain rate than class I dogs (P = 0.006) and controls (P = 0.001). Other deformations, including longitudinal deformations, were not significantly different between classes of CMVI or between CMVI dogs and controls.ConclusionsIn the clinical progression of CMVI in dogs, myocardial deformations, as assessed by 2D-STE, differed according to myocardial contractile direction. Thus, assessments of multidirectional myocardial deformations may be important for better assessment of clinical cardiac function in dogs with CMVI.     

Effect of age on myocardial function assessed by two-dimensional speckle-tracking echocardiography in healthy beagle dogs

ObjectivesThe objective of this study was to evaluate the effect of age on myocardial function assessed by two-dimensional speckle-tracking echocardiography (2D-STE) in healthy dogs.AnimalsThirty-two healthy Beagles were used.MethodsMyocardial function was assessed in each dog by using 2D-STE, and the results were compared between young and old dogs.ResultsThe myocardial deformations in systole, besides the apical rotation rate, were not significantly different between young and old dogs. In contrast, the early diastolic circumferential strain rate, basal rotation rate, and torsion rate were significantly lower in old dogs than in young dogs (P = 0.03, P = 0.033, and P = 0.015, respectively). Late diastolic longitudinal and radial strain rates were significantly higher in old dogs than in young dogs (P = 0.002 and P = 0.018, respectively).ConclusionsYoung and old dogs showed similar systolic myocardial deformations, but significant differences in the values of some diastolic deformation variables were found between young and old dogs, highlighting the need for using age-matched control subjects in studies of diastolic function.