Effect of Oxidizing Power of Roots on Iodine Uptake by Rice Plants

Although iodine is harmful to plants, rice plants ( Oryza sativa L.) absorbed iodine more selectively than bromine. To explain this selective absorption, the authors proposed the following hypothesis based on the fact that the standard redox potential for (I₂+ 2e = 2I⁻) is lower than that for (Br₂+ 2e = 2Br⁻) and (Fe³⁺+ e = Fe²⁺), and the roots of rice plants are able to oxidize ferrous ion (Fe²⁺) into ferric ion (Fe³⁺), namely rice plants oxidize iodide ion (I⁻) to form molecular iodine (I₂) via the oxidizing power of their roots, and absorb the molecular iodine formed more selectively than iodide ion. Bromine, by contrast, is absorbed by rice plants only in the form of ion (Br⁻). According to this hypothesis, there should be a significant correlation between the oxidizing power of the rice roots and the amount of iodine absorbed. Therefore, the relationship between the oxidizing power of the roots and the concentration of iodine absorbed was studied in a water culture using 8 varieties of rice plants. Rice seedlings, 14 d after germination, were cultured in a solution containing 1 mg L⁻¹ each of iodide and bromide ions for 3 d. The oxidizing power of the rice roots was evaluated based on the amount of 1-naphthylamine oxidized by the roots. A significant correlation (0.78, n = 16, 0.1% significant level) was found between the oxidizing power and the concentration of iodine absorbed by the roots. However, no relationship was found between the oxidizing power of the roots and the amount of bromine absorbed.     

Birth of piglets through the non-surgical transfer of blastocysts produced in vitro

In this study, we attempted to produce piglets by non-surgically transferring blastocysts produced in vitro, using a flexible catheter as the transfer instrument. Cumulus-oocyte complexes (COCs) were aspirated from the follicles of ovaries obtained at a local slaughterhouse. They were then matured in modified North Carolina State University (NCSU)-37 medium for 44-46 h and fertilized in porcine gamete medium (PGM). Ten hours after in vitro fertilization (IVF), presumptive zygotes were removed from the cumulus cells and cultured in porcine zygote medium (PZM)-5. Blastocysts were cultured for five days after IVF and, using a catheter for deep intrauterine insemination without sedation, they were transcervically transferred into the uterine horn of six recipients (45-50 blastocysts/recipients) whose estrous cycles were synchronized, at 5 days after human chorionic gonadotropin (hCG) injection. Of the six recipients, one sow became pregnant and farrowed seven piglets (four live piglets) 119 days after hCG injection. The body weight at birth of the newborns ranged from 0.8 to 1.4 kg. These results indicate that it is possible to obtain piglets by transcervically transferring blastocysts produced by IVF and in vitro cultures in chemically defined media.     

A time-course study of flavonoids in the sprouts of tartary (Fagopyrum tataricum Gaertn.) buckwheats

The evolution, from 1 to 10 days after germination, of flavonoid content in sprouts of tartary buckwheat (Fagopyrum tataricum Gaertn.), grown in a greenhouse under low light conditions (16 μmol m⁻² s⁻¹), was investigated. Chlorogenic acid and flavonoids including C-glycosylflavones (orientin, isoorientin, vitexin, isovitexin), rutin and quercetin were separated from the sprouts by HPLC and quantified with their commercial standards. Rutin content in the edible portion of the sprouts (mean 20 and 37 mg g⁻¹ DW in ‘Hokkai T 8’ and ‘Hokkai T 10’, respectively) was 3- to 31-fold greater than that in the roots or pericarp. The free radical scavenging activity of seed sprouts was assessed through the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. From 6 to 10 days after sowing, the free radical scavenging activity in the edible portions rose significantly from 1.52 to 2.33 μmol Trolox equiv. g⁻¹ DW in ‘Hokkai T 8’ and from 1.46 to 2.09 μmol Trolox equiv. g⁻¹ DW in ‘Hokkai T 10’, but differences between ‘Hokkai T 8’ and ‘Hokkai T 10’ were not significant. As the results, the sprouts of tartary buckwheat, particularly those of ‘Hokkai T 10’ are strongly recommended as new high rutin food.     

Effects of leptin and leptin peptide amide on the release of luteinizing hormone, growth hormone and prolactin from cultured porcine anterior pituitary cells

The present study was carried out to determine whether leptin or leptin (116–130) peptide amide (lep (116–130)), an active fragment of the native protein in rats, is able to stimulate the release of luteinizing hormone (LH), growth hormone (GH) or prolactin (PRL) from cultured porcine anterior pituitary (AP) cells in vitro. The AP cells were obtained from 6 month‐old pigs and were incubated for 3 h with 10^?11?10^?7 mol/L leptin or lep (116–130) after being cultured in Dulbecco's modified Eagle's medium for 3–4 days. Leptin significantly increased the concentration of LH and GH in the culture medium at concentrations of 10^?8 and 10^?7 mol/L, respectively, compared with the controls (P < 0.05). Leptin did not increase the concentration of PRL in the culture medium. In contrast to these results, no effects of lep (116–130) on the release of LH, GH or PRL were seen in the cultured cells. These results suggest that leptin stimulates the release of LH and GH by acting directly on porcine AP cells, and that a fragment of leptin protein comprising amino acids 116–130 is not associated with the secretion of hormones in pigs.     

Effects of intracerebroventricular injections of leptin on the release of luteinizing hormone and growth hormone in castrated calves

The purpose of the present study was to clarify the hypothalamic action of leptin on the secretion of luteinizing hormone (LH) and growth hormone (GH) in cattle. Intracerebroventricular (the third ventricle) injections of leptin were given to fully fed castrated Holstein calves. Blood samples were collected at 10‐min intervals for 60 min after injection and 20‐min intervals for 60 min before injection and for 60–180 min after injection through an indwelling catheter in the external jugular vein. Plasma LH and GH levels were examined by homologous radioimmunoassay. The administration of 10 µg of leptin stimulated a significant (P < 0.05) release of GH but not LH. Average GH levels began to rise after 30 min and were significantly increased at 40, 50 and 60 min after the injection, compared with the respective control values (P < 0.05). The present result suggests that leptin may act partly on the hypothalamus to stimulate the release of GH in castrated calves.     

The preventive effect of Bacillus subtilus strain DB9011 against experimental infection with enterotoxcemic Escherichia coli in weaning piglets

Porcine edema disease (ED) is caused by Shiga toxin 2e‐producing Escherichia coli (STEC). Post‐weaned piglets often suffer from ED as a result of intestinal infection with STEC, which causes impaired growth performance and high mortality. Antimicrobial therapy is a curative treatment for piglets infected with STEC, but the emergence of antimicrobial‐resistant STEC has become a serious problem for Japanese pig farmers. Therefore, an alternative strategy other than antimicrobial therapy is needed for the prevention or treatment of ED. In this study, we evaluated the effect of oral administration of Bacillus subtilis DB9011 (DB9011) to prevent the experimental infection of STEC in weaning piglets. Eight 21‐day‐old piglets were divided into two groups: STEC challenge with the basal diet, and STEC challenge with DB9011 supplemented diet. The challenge was carried out when the animals were 25, 26 and 27 days old using STEC contained in capsules resistant against gastric digestion. All pigs were euthanized at 36 days of age. DB9011 improved the symptoms of ED and decreased the number of STEC in the ileal digesta and feces. Accordingly, oral administration of DB9011 in weaned piglets prevents ED through the suppression of the growth of STEC in the ileum.     

Anti-Thy-1 Antibody-mediated Complement-dependent Cytotoxicity is Regulated by the Distribution of Antigen,Antibody and Membrane Complement Regulatory Proteins in Rats

Some therapeutic antibodies as anticancer agents exert their effects through the host immune system, but the factors that predict their cytotoxicity, including complement-dependent cytotoxicity (CDC), are unclear. In the present study, we attempted to elucidate some of these factors in a preclinical model. CDC-related mesangiolysis caused by administration of the anti-Thy-1.1 antibody can be studied in the rat anti-Thy-1 glomerulonephritis model, so the model was used in this study. Three animals each were sacrificed at 0.5, 1, 8, 24 and 48 hours after i.v. administration of the anti-Thy-1.1 antibody at 1mg/kg. The distribution of the Thy-1.1 antigen and 2 membrane complement regulatory proteins (mCRPs), Crry and CD55, in three non-treated animals and the distribution of the injected antibody and C3 in the model was studied by immunohistochemistry. In the mesangial cells of the kidney, both expression of the antigen and distribution of the antibody with C3 deposition were observed with weak expression of mCRPs. There was also antigen and antibody distribution in the medullary cells of the adrenal gland and in the lymphocytes of the thymus but no C3 deposition, which was thought to be related to high expression of mCRPs. The antigen was observed in several other organs and tissues without distribution of the antibody. Cell death was only observed in the mesangial cells. These results clearly demonstrate that activation of CDC is regulated by several factors, such as distribution of the target molecule, antibody distribution and the balance among the molecules of the CDC cascade and mCRPs.