Negative Coulomb drag in a one-dimensional wire

We observed negative Coulomb drag for parallel coupled quantum wires, in which electrons flow in the opposite directions between the wires. This only occurred under the conditions of strong correlation in the wires, that is, low density, high magnetic field, and low temperature, and cannot be addressed by a standard theory of momentum transfer. We propose a Coulomb drag model in which formation of a Wigner crystal state in the drag wire and a particle-like state in the drive wire is taken into account.     

Genetic diagnosis of band 3 deficiency and sexing in bovine preimplantation embryos

Band 3 deficiency with hereditary spherocytosis and hemolytic anemia in Japanese black cattle, band 3(Bov.Yamagata), is caused by a total lack of band 3 protein with an autosomal dominant inheritance. Genotyping for band 3 deficiency and sexing were successfully achieved in biopsied embryo cells with efficiencies of 98.4% and 97.4%, respectively. Transfer of the embryo that was determined as homozygous for the mutant allele into a recipient cow resulted in the production of a fetus exhibiting the genotype and red cell phenotypes characteristic of band 3(Bov.Yamagata). These results demonstrate that our procedure is reliable and applicable to produce animals free from or homozygous for the mutant allele by breeding carrier animals.     

Medullary sponge kidney in a 10-year-old Shih Tzu dog

Medullary sponge kidney was diagnosed in a 10-year-old male Shih Tzu dog with a long history of hyposthenuria, but with no other findings indicating renal failure or hormonal aberration. At the dog's death from heart failure, an autopsy was performed. On gross morphology, bilateral kidneys were normal size and had many cysts ranging from the corticomedullary junction to renal papillae. Histopathologic findings showed that almost all of the cysts were lined by monolayered or multilayered and columnar or cuboidal epithelium with chilium similar to epididymis. Immunohistochemically, all of these cells were strongly positive for AE1/AE3 and negative for vimentin. Many of these cells were positive for cytokeratin 7 (CK7), and only a few cells were positive for desmin. The results of staining are the same as those for epithelium of the collecting duct of normal canine kidney. This is the first report of this pathologic entity in the canine kidney.     

Ingested delphinidin-3-rutinoside is primarily excreted to urine as the intact form and to bile as the methylated form in rats

Many reports have described the bioavailability of anthocyanins; however, most of these reports investigated only the amount of anthocyanins excreted in urine. In the present study, we calculated the pharmacokinetic bioavailability of anthocyanins in rats by measuring the plasma concentration of delphinidin-3-rutinoside that had been administered orally or intravenously. Delphinidin-3-rutinoside was primarily absorbed in the blood and excreted into urine as unmetabolized forms with a T(max) of 26.3 min and a C(max) of 0.285 +/- 0.071 micromol/L. We detected small amounts of the metabolite 4'-O-methyl-delphinidin-3-rutinoside in the plasma, but we detected neither anthocyanidin (aglycone) nor glucuro- or sulfoconjugates. For the 8 h period after intake, delphinidin-3-rutinoside and 4'-O-methyl-delphinidin-3-rutinoside were excreted to urine at 795 +/- 375 and 12.3 +/- 2.91 nmol, respectively. Relative to intravenous injection, oral administration of delphinidin-3-rutinoside resulted in complete bioavailability (0.49 +/- 0.06%). Analysis of delphinidin-3-rutinoside plasma concentrations in bile cannulated rats revealed that, for the 8-h period after intake, the intact delphinidin-3-rutinoside excretion ratio in bile was 11% of the excretion ratio of 4'-O-methyl-delphinidin-3-rutinoside, 1.91 +/- 0.35 nmol versus 17.4 +/- 8.67 nmol, respectively. Setting the bile duct cannulation in a Bollman-type cage, however, significantly increased the bioavailability of orally administered delphinidin-3-rutinoside (18.14 +/- 6.24%). This effect appears to stem immobilization stress by reducing gastrointestinal motility. The cumulative excretion of delphinidin-3-rutinoside and 4'-O-methyl-delphinidin-3-rutinoside in urine and bile was 2.67 +/- 1.24% (w/w) of the dose ingested. Studies report that several metabolites are formed after oral ingestion of anthocyanins. Examples include glucuronyl from cyanidin-3-glucoside and both glucuronyl and sulfate conjugates from pelargonidin-3-glucoside. Our results indicate that delphinidin-3-rutinoside might be metabolized differently from cyanidin-3-glucoside and pelargonidin-3-glucoside.     

Quantitative trait loci for whiteness of cooked rice detected in improved rice cultivars in Hokkaido

Improving the eating quality of cooked rice has been one of the most important objectives in rice breeding programs. Eating quality of cooked rice is a complex trait including several components, such as external appearance, taste, aroma, and texture. Therefore, dissection of these components followed by marker-assisted selection of detected QTL(s) may be a useful approach for achieving desirable eating quality in rice breeding. Whiteness of cooked rice (WCR) is an important factor related to the external appearance of cooked rice. WCR is known to be associated with the amylose and protein contents of the endosperm. However, the genetic basis of WCR remains unclear. In this study, we evaluated phenotypic variation in WCR among recently developed rice cultivars from Hokkaido, Japan. Then, we developed doubled haploid lines (DHLs) derived from a cross between two cultivars from Hokkaido, Joiku No. 462 (high WCR) and Jokei06214 (low WCR). Using the DHLs, we detected two QTLs for WCR, qWCR3 and qWCR11, on chromosomes 3 and 11, respectively. We also examined the dosage effect of the two QTLs based on both the categorized segregants in the DHLs and the relationship between the WCR phenotype and inheritance around the QTL regions in cultivars from Hokkaido.     

Urinary excretion of 5-(3',4'-dihydroxyphenyl)-gamma-valerolactone, a ring-fission metabolite of (-)-epicatechin, in rats and its in vitro antioxidant activity

There is great interest in the nutritional potential of (-)-epicatechin, a common polyphenolic constituent of many foods and beverages, because of its potent antioxidant capacity. To better evaluate the biological role of (-)-epicatechin, we studied the urinary excretion of 5-(3',4'-dihydroxyphenyl)-gamma-valerolactone, a ring-fission metabolite of (-)-epicatechin by intestinal microflora, in rats as well as its antioxidant activity in vitro. The method for measuring the urinary levels of (-)-epicatechin and 5-(3',4'-dihydroxyphenyl)-gamma-valerolactone was based on the enzymatic hydrolysis of beta-glucuronidase and sulfatase, and was subsequently determined by HPLC coupled to an electrochemical detector. Following administration of (-)-epicatechin at doses of 0, 20, 40, and 80 mumol per rat, (-)-epicatechin and 5-(3',4'-dihydroxyphenyl)-gamma-valerolactone were excreted into the urine within 24 h in a dose-dependent manner. Urinary 5-(3',4'-dihydroxyphenyl)-gamma-valerolactone was mostly in the conjugated form, with a higher ratio of conjugation than (-)-epicatechin. We assessed the relative antioxidant potentials for scavenging radicals in the aqueous phase as expressed in the Trolox equivalent antioxidant capacity (TEAC). The results demonstrated that the degradation of (-)-epicatechin into 5-(3',4'-dihydroxyphenyl)-gamma-valerolactone attenuated the antioxidant ability of the former. However, 5-(3',4'-dihydroxyphenyl)-gamma-valerolactone showed stronger antioxidant activity than l-ascorbic acid. These results led us to suppose that 5-(3',4'-dihydroxyphenyl)-gamma-valerolactone, a microbial metabolite of (-)-epicatechin, circulating in the body may also at least be biologically active in terms of contributing to its combined antioxidant effect.     

Stimulatory effect of cyanidin 3-glycosides on the regeneration of rhodopsin

Anthocyanins have been suggested to improve visual functions. This study examined the effect of four anthocyanins in black currant fruits on the regeneration of rhodopsin using frog rod outer segment (ROS) membranes. Cyanidin 3-glycosides, glucoside and rutinoside, stimulated the regeneration, but the corresponding delphinidins showed no significant effect. The formation of a regeneration intermediate was suggested to be accelerated by cyanidin 3-rutinoside. Their effects on the cGMP-phosphodiesterase activity in the ROS membranes were also investigated but found to be negligible. It was concluded that the major effect of anthocyanins in rod photoreceptors is on the regeneration of rhodopsin.     

Induction of short-term pseudopregnancy in gilts by the administration of estradiol benzoate or estradiol dipropionate to achieve ovulatory synchronization for embryo collection

A study was conducted to investigate whether ovulation in gilts could be synchronized for embryo collection by the administration of estradiol benzoate (EB) or estradiol dipropionate (EDP) to induce pseudopregnancy, followed by the treatment with prostaglandin F_2α (PGF_2α) on 10 days after. Ten gilts each received a total of 20 mg of EB or EDP on Day 10 or EB on Day 10 and 14 to induce pseudopregnancy (Day 0 = onset of estrus). Donors received PGF_2α 10 or 15 days (as a control) after the first administration of estrogens and subsequently eCG and hCG, and were then inseminated artificially. The embryos were collected 7 days after the administration of hCG, and assessed for embryo yield and their developmental stages. All protocols resulted in good embryo yield (9.8–13.2 embryos in average), and the embryos showed average ability to develop to the expanded blastocyst stage (3.29–4.03 as developmental scores) without any significant differences among the protocols. These results suggest that the administration of PGF_2α 10 days after the treatment of gilts with EB or EDP would allow synchronization of ovulation and embryo collection, as well as shortening the period from estrus detection to embryo collection, thus improving embryo collection efficiency.     

Prepartum maternal plasma glucose concentrations and placental glucose transporter mRNA expression in cows carrying somatic cell clone fetuses

In this study, the plasma glucose concentrations of cows carrying a somatic cell clone fetus during late pregnancy and placental glucose transporter (GLUT) mRNA levels at parturition were examined. Parturition was induced using dexamethasone, prostaglandin F(2α) and estriol in cows bearing a clone (Clone) or a fetus fertilized in vivo as a control (DEX). Plasma glucose concentrations were measured in the cows (days 257 and 271 of pregnancy and at parturition) and newborn calves. Cotyledon and caruncle tissues removed just after parturition were used for mRNA extraction. Expression of mRNA was also analyzed in control cows that were induced to undergo parturition without dexamethasone (PG) or that spontaneously delivered (SP). The glucose concentrations of the Clone group were significantly low at all points examined, but those of the calves were normal. The increase in the maternal glucose concentration from day 257 to parturition was significantly lower in the Clone group. Glucose concentrations were negatively correlated with birth weight for clones (day 257; r=-0.584, day 271; r=-0.286, parturition; r=-0.549). There was no difference in mRNA levels in the cotyledons among the animals examined. In the caruncles, the Clone and PG groups showed significantly higher GLUT1 and GLUT3 mRNA levels than the SP group, and the GLUT3 mRNA level was significantly higher in the Clone group than in the DEX group. The glucocorticoid receptor α mRNA level was significantly lower in the SP group than in the DEX group. Although spontaneous parturition and administration of dexamethasone suppressed the placental GLUT mRNA levels, the action was not observed in clone pregnancy. These results raise the possibility of facilitation of glucose transportation through the placenta to meet increased nutritional requirements of overgrown clone fetuses.     

Fundamental studies on the physiology of rotifers in mass culture—V. Dry Chlorella powder as a food for rotifers

The dietary value of dried, commercial Chlorella was compared with that of living marine Chlorella, and yeast, in relation to growth of the rotifer Brachionus plicatilis raised individually and by batch culture methods.A concentration of 50 μg/ml of dried Chlorella powder is near an optimal density for rotifer growth. The dried material in suspension is less effective for growth than living marine Chlorella, although it is much more effective than a suspension of yeast at the same density (50 μg/ml).In batch culture (12-l glass vessel), the rotifers grew from an initial inoculation of 13.2 individuals/ml to a density of 434 individuals/ml by the 16th day. About 10⁷ rotifers could be removed from one batch culture in five harvests in the 41-day experimental period.The results indicate that dried Chlorella powder is an effective food for the rotifer Brachionus plicatilis.