Maternal high‐fat diet promotes onset of diabetes in rat offspring

The onset and progression of type II diabetes is closely related to environmental factors, in particular dietary habit. Moreover, the environmental exposures very early in life can influence the risk for development of type II diabetes later in life. In this study, we investigated pathophysiological changes in the pups of maternal Spontaneously Diabetic Torii (SDT) rats that were fed a high‐fat diet (HFD) throughout gestation and lactation. Maternal SDT rats were continued on HFD for 5 weeks, from day 8 of gestation to day 21 after birth, and biological analyses of the pups were performed from 2 to 22 weeks of age. Results of serum lipid levels in pups from dams fed HFD were higher than pups from dams fed a standard diet, and the onset of diabetes was significantly accelerated in pups from dams fed HFD. In pathological analyses, pups from dams fed HFD showed increases in liver weight and vacuolation of hepatic cells at 2 weeks of age. In conclusion, the metabolic disorder of lipids and glucose in SDT rats is closely related to the nutritional condition of dams during the periods of gestation and lactation.     

Hypothalamic dopamine is required for salsolinol‐induced prolactin secretion in goats

The aim of the present study was to clarify the relationship between hypothalamic dopamine (DA) and salsolinol (SAL) for the secretion of prolactin (PRL) in goats. SAL or thyrotropin‐releasing hormone (TRH) was intravenously injected into female goats treated with or without the D₂ DA receptor antagonist haloperidol (Hal), which crosses the blood‐brain barrier, and the PRL‐releasing response to SAL was compared with that to TRH. PRL‐releasing responses to SAL, Hal, and Hal plus SAL were also examined after a pretreatment to augment central DA using carbidopa (Carbi) and L‐dopa. The PRL‐releasing response to Hal alone was greater than that to SAL or TRH alone. The PRL‐releasing response to Hal plus SAL was similar to that of Hal alone. In contrast, the PRL‐releasing response to Hal plus TRH was greater than that to TRH or Hal alone. The treatment with Carbi plus L‐dopa inhibited SAL‐ and Hal‐induced PRL secretion. The inhibition of the PRL‐releasing response to SAL disappeared when SAL was injected with Hal. These results indicate that the mechanisms underlying the SAL‐induced PRL response differ from those of TRH, and suggest that hypothalamic DA and its synthesis is associated in part with SAL‐induced PRL secretion in goats.     

Gibberellin is not a regulator of miR156 in rice juvenile-adult phase change

Plant hormone gibberellin (GA) promotes juvenile-adult phase change in higher plants. To confirm the functions of GA in rice, I used dwarf mutant d18-dy. d18-dy is a loss-of-function allele of D18, which encodes GA3ox2. d18-dy mutant exhibited long juvenile phase in morphological traits such as the size of the shoot apical meristem (SAM), shape of leaf blades, presence or absence of midribs and node–internode differentiation in stem. In contrast, expression patterns of juvenile-adult phase change markers miR156 and miR172 were similar between wild type and d18-dy. In addition, d18-dy mutation and GA did not affect expression levels of downstream genes of miR156. GA does not function upstream of miR156 in juvenile-adult phase change.     

Development of bovine embryos cultured in CR1aa and IVD101 media using different oxygen tensions and culture systems

The aim of the present study was to optimise the culture conditions for the in vitro production of bovine embryos. The development of in vitro fertilised bovine oocytes in CR1aa supplemented with 5% calf serum and IVD101 culture media were compared using traditional microdrops and Well of the Well (WOW) culture systems either under 5% or 20% oxygen tension. After 7 days of culture, a significantly higher blastocyst formation rate was obtained for embryos cultured in CR1aa medium compared to those cultured in IVD101, irrespective of O2 tensions and culture systems. The blastocyst formation in IVD101 was suppressed under 20% O2 compared to 5% O2 . Despite their similar total cell numbers, higher rates of inner cell mass (ICM) cells were observed in blastocysts developed in IVD101 medium than in those developed in CR1aa, irrespective of O2 tensions. There was no significant difference in blastocyst formation, total, ICM and trophectoderm (TE) cell numbers between embryos obtained by microdrop and WOW culture systems irrespective of the culture media and O2 tensions used. In conclusion, CR1aa resulted in higher blastocyst formation rates irrespective of O2 tension, whereas IVD101 supported blastocyst formation only under low O2 levels but enhanced the proliferation of ICM cells.     

Sensitivity to cadmium of the standard test species Folsomia candida compared to two other species, Onychiurus yodai and Sinella umesaoi (Collembola)

Knowing whether test species used for single-species toxicity tests are representative of other species provides valuable information because contaminant effects are often extrapolated to the community level based on these tests. To evaluate how representative the sensitivity of the standard test collembolan species Folsomia candida is for Collembola, we devised toxicity tests using the collembolan species Onychiurus yodai and Sinella umesaoi, which exhibit life-forms different from F. candida. Sensitivity to cadmium (Cd) was compared between F. candida and the novel test species. The 50% effective concentrations for reproduction were 154.7, 72.2 and 40.9 mg Cd/kg dry soil for O. yodai, F. candida and S. umesaoi, respectively. Thus, the reproductive sensitivity of F. candida to Cd was between that of the other two species. Increasing reproductive sensitivity to Cd corresponded to increasing activity levels and a more surface-dwelling life-form. Our data may facilitate the generalisation of effect data for F. candida to other species.     

Effects of feeding dried distillers grains with solubles (DDGS) on meat quality at the late stage of the fattening period of Holstein steers

Feeding dried distillers grains with solubles (DDGS) during the late stage of the fattening period of Holstein steers was studied in regard to the influence on meat quality. Sixteen Holstein steers approximately 18 months old were used in this study. Eight animals were fed commercial concentrated feed for the entire fattening period. The other eight animals were fed 15% DDGS in the concentrated feed for 3 months before slaughtering. The moisture, ether extract and crude protein from both groups was approximately the same. The thiobarbituric acid reactive substance (TBA) value of storage for 7 days at 5°C from the animals fed DDGS showed a tendency to be lower (P = 0.059). The change in the TBA value during storage was also lower for the animals not fed DDGS (P < 0.05). There were no differences in the subcutaneous fat color between the two groups. The a*(measure of redness) and b*(measure of yellowness) of the M. longissimus from the animals fed DDGS showed a tendency to be lower (P = 0.051, 0.070). The fatty acid composition of the M. longissimus, subcutaneous and perirenal fat were not widely influenced by the feeding of DDGS. It is suggested that feeding 15% DDGS during the late stage of the fattening period for Holstein steers reduced the oxidation of the beef.     

Effects of reactive radicals and heat on <Emphasis Type="Italic">trans</Emphasis>-isomerization of eicosapentaenoic acid

Trans geometric isomers of eicosapentaenoic acid (TEPA) have been found as minor components in human platelets. However, there is little information on the mechanism of trans-isomerization of eicosapentaenoic acid (EPA) in vitro and in vivo. The effects of reactive radicals and heat on trans-isomerization of EPA were examined. Trans-isomerization occurred when EPA ethyl ester reacted with nitrogen dioxide radical (NO₂) but not with 2,2′-azobis(2,4-dimethylvaleronitrile). TEPA was also produced from EPA ethyl ester heated at 200°C for 60 h. No TEPA, however, was detected in sardines Sardinops melanostictus after boiling, roasting, or microwave heating. These results suggest that EPA is trans-isomerized by NO₂ in vivo while trans-isomerization of EPA does not occur during conventional cooking.     

Isolation and identification of DPPH radical scavenging compounds in Kurosu (Japanese unpolished rice vinegar)

Dihydroferulic acid (DFA) and dihydrosinapic acid (DSA) were isolated from Kurosu (unpolished rice vinegar) as the major constituents responsible for Kurosu's radical scavenging activity. The levels of antioxidative activity of DFA and DSA in DPPH radical scavenging were higher than those of their respective structurally related compounds, ferulic acid and sinapic acid. The concentrations of DFA and DSA were low in common rice vinegar (polished rice vinegar), suggesting that Kurosu is more advantageous than rice vinegars as an antioxidative food item. As the concentrations of DFA and DSA were low in unpolished rice, too, these acids are thought to be produced in Kurosu through the process of the fermentation from ferulic acid and sinapic acid, respectively.     

Isolation of Getah virus from dead fetuses extracted from a naturally infected sow in Japan.

Three viruses producing a cytopathic effect in cell culture were isolated from dead fetuses extracted from a naturally infected sow, and were found to be serologically identical by neutralization tests. One of the viruses was cloned and named the Sakura strain. The Sakura strain was identified as Getah virus by cross-neutralization tests.