Liu Asato

The Effects of Oral RNA and Intraperitoneal Nucleoside-Nucleotide Administration on Methicillin-Resistant Staphylococcus aureus Infection in Mice

The effects of oral RNA and intraperitoneal nucleoside-nucleotide mixture administration on methicillin-resistant Staphylococcus aureus (MRSA) strain 8985N infection were studied in mice. BALB/c mice were fed a nucleic acid-free diet or nucleic acid-free diet supplemented with 0.5% or 2.5% ribonucleic acid (RNA) for 30 days. Nucleoside-nucleotide mixture or saline (control) was intraperitoneally administered daily to these rats except for the 2.5% RNA group, which received saline only. On the 10th day of this treatment, the mice were inoculated intravenously with the viable MRSA organisms. Susceptibility to the MRSA was determined by animal survival and recovery of the MRSA from the organs. The survival rates in the three groups that were administered saline were 29%, 35%, and 40% for nucleic acid-free diet, 0.5% RNA, and 2.5% RNA groups, respectively, whereas in the two groups that received the nucleoside-nucleotide mixture the rates were 69% for the nucleic acid-free diet group and 55% for 0.5% RNA group. The susceptibility of the mice to the MRSA challenge was not affected by dietary RNA, which indicates the ineffectiveness of oral RNA. The combined survival rate in the two nucleoside-nucleotide groups (64%) was statistically different (p < .01) from that in the three saline groups (34%). There was a greater reduction in viable organism recovery in the kidney and spleen of the surviving mice that had been administered the nucleoside-nucleotide mixture than in those administered saline.(ABSTRACT TRUNCATED AT 250 WORDS)

Favorable effects of egg white protein on lipid metabolism in rats and mice

Abstract Egg is a cholesterol-rich food and has a strong hyper-cholesterolemic action. However, all the cholesterol is in egg yolk and egg white is cholesterol-free. The effect of egg white protein and its hydrolysates on the serum lipids were compared with casein and soybean protein in rats and mice. The animals were given 30% casein diet (Ca group) or diets of 15% casein plus 15% soybean protein isolate (SPI group), egg white protein (EW group) or egg white protein hydrolysates (EW-P group) for 3 (rats) or 2 (mice) weeks. Food intake and growth were very similar among the different dietary groups. Hypocholesterolemic effect was observed in SP, EW and EW-P groups in rats and EW group in mice. Prevention of the reduction of HDL-cholesterol was found in EW and EW-P groups in rats and EW-P group in mice. The result suggests the possibility of the use of egg white for the prevention and treatment of hyper-cholesteremia.

EFFECT OF DIETARY PEPTIDES ON PLASMA LIPIDS AND ITS MECHANISM STUDIED IN RATS AND MICE

The present 4 experiments were planned to confirm our hypothesis that small quantity of intraluminal peptides enters into circulatory system and affects on lipid metabolism. In Experiments 1 and 2, rats and mice were fed diets of casein or two casein hydrolysate peptides for 2 and 3 weeks, respectively. Hypocholesterolemic effect in one of the peptides was observed in both animals. In Experiment 3, we administered small amount of the above peptides, amino acid mixture simulating casein pattern or saline to mice through tail vein daily for 10 days. Hypocholesterolemic effect was observed in the mice administered peptides but not in the mice administered saline and the amino acid mixture. In Experiment 4, entry of peptides into the circulatory system was shown with the everted sac of rat intestine. These results may indicate that small quantity of intraluminal peptides enter the circulatory system from lumen and affect on lipid metabolism.

Comparative effect of amino acid mixtures with or without asparagine and glutamine on growth of rats

Abstract When proteins, peptides and amino acid mixtures are compared, some amino acid mixtures include asparagine and/or glutamine and others do not. Therefore in this experiment we studied the effect of the presence or absence of these amino acids on the growth and nutritional status of rats. Rats weighing about 65 g were divided into 4 groups and fed experimental diets for 21 days. The diets contained 11% casein (N=1.57%, group A), 10% amino acid mixture (N=1.57%, including asparagine and glutamine, group B), 10% amino acid mixture (N=1.25%, excluding asparagine and glutamine, group C), or 12.5% amino acid mixture (N=1.57%, excluding asparagine and glutamine, group D). In group D we increased amino acid concentration to 12.5% in order to make N concentration same as the diets of groups A and B. Daily food intake, body weight gain and hematologic values were measured. Most of the indicators of groups A, B and C were similar and lower than those of group D. The results suggest that amino acid mixtures excluding asparagine and glutamine have the same effect as protein and the mixture including these amino acids on growth and nutritional status of young rats but overestimates the effect when total N concentration is increased to the level of protein.

Influence of time lag in amino acid absorption on nitrogen retention in rats

Abstract Depending on the form of nitrogen sources, there is a time lag in amino acid absorption. However, the influence of such a time lag on nitrogen retention is not known. In the present experiment we created a time lag in amino acid absorption and observed nitrogen retention in rats. Two unbalanced amino acid mixtures were prepared. The equal amount of combination of these mixtures makes the amino acid pattern of egg protein. Rats were given these two unbalanced amino acid mixture diets alternatively at 08:00–09:30 hr, 11:00–12:30 hr, 14:00–15:30 hr, and 17:00–18:30 hr for 14 days. Control rats were given egg-protein-pattern amino acid mixture diet at the same time and periods as the experimental group. Dietary amino acid levels were 5% and 10%. Although the control and experimental rats ate similar amounts of each amino acid, there was a time lag in the amino acid absorption. Plasma aminograms, hematologic values, body protein concentration, and growth were very similar. The results indicate that nitrogen utilization is not influenced by a relatively small time lag in amino acid absorption.

Dietary nucleoside-nucleotide mixture aggravates nasal allergic responses induced by toluene diisocyanate in mice

Abstract In this study we evaluated the effect of a dietary nucleoside-nucleotide mixture (NNM) on nasal allergy induced by toluene diisocyanate(TDI) in mice. Female ddY mice were randomized into two groups and fed a nucleic-acid free 20% casein (control) or this diet supplemented with NNM for 4 weeks. On the 4th week, mice were divided into 2 sub-groups; NNM sensitized, NNM- nonsensitized, control-sensitized and control-nonsensitized. The sensitized groups of mice were treated with two courses of intranasal application of 5% TDI in diethyl acetate for 5 consecutive days each time, separated by one week rest. Nonsensitized group of mice were similarly treated with vehicle. A week after the second sensitization all the treatment groups were provoked by applying 2.5% of TDI in vehicle. Nasal responses of sneezing, rhinorrhea, itching and snort at provocation, were scored for ten minutes. Degree of hair loss from the snout of mice was also scored for the length of the experiment. Lung and serum IgE were measured by ELISA. Results show that the sensitized groups of mice from each dietary group sneezed more frequently than the nonsensitized groups (p

Analyses of Dietary Habits and Food Items Consumed by Japanese Female Students in Seven Different Cities.

1) 今日の食品の市場に出回る数は多い。現在の日本の女子学生は134万人である。このような状況下にあって今日の女子学生はどれだけの食品を摂取しているのだろうかについて, 福岡市城南区, 高知市旭天神町, 岡山市伊島町, 吹田市藤白台, 松戸市相模台, 仙台市青葉区および網走市字八坂の各大学に平均女子学生数1, 300人が在籍するうち, 栄養・食品学を選考する19歳から21歳の女子学生を対象に, 各地において20人以上, 調査期間は3日間 (1989年の10月から11月) の調査をした。2) 2, 718回の全食事回数 (各地平均388回) の解析の結果, 1回の食事および1日の摂取食品数は, それぞれ10.2品目および26品目であった。摂取食品数は, 各地域において統計的に差がなかった。3) 摂取食品のうち, 重複のない食品数は平均は380品目であった。理論的最大摂取食品数550～620品目であった。4) 各調査地域において摂取された上位35位の食品の共通摂取食品数は16品目あった。その共通品目はxx2検定で, なんら地域間の差はなかった。5) 低頻度摂取食品のなかで, 3回, 2回および1回摂取された食品数は, それぞれ全食品数のうち, 9.0%, 14.7%, 33.9% (計57.6%) となって, 摂取回数あるいは摂取頻度が低くなるにつれ食品数は多くなっていた。3回摂取以下の食品数は全食品数の約3分の2に相当した。それぞれの地域の低摂取頻度の摂取食品数に対する比率 (%) は1回から3回までのそれぞれの値においてxx2検定で, なんら統計的に差はなかった。6) 摂取食品のABC分析の結果, 全摂取頻度の50%および75%を占めるにはそれぞれ30品目および71品目であった。残り4分の1は地域によって異なり, 250品目から350品目で占められていた。7) 18食品群でみた摂取食品数ではとくに野菜類と魚介類, 穀類, 果実類, 菓子類および調味料・香辛料類であった。一方, 品目数の少ない食品群はタマゴ類, 油脂類および種実類であった。これらの食品数は, 調味料・香辛料類は別として, 食品成分表のそれぞれの食品群の食品数に対応していた。成分表にない食品類のどの地域においてもかなりの数であった。8) 厚生省の1日30品目推奨値は多いことを考察した。9) 低摂取頻度食品および成分表にない食品の品目数は多く, とくに後者は, 代表食品群として換算されるため, 栄養摂取量換算においてかなり困惑をもたらすものと考察した。10) 摂取食品の地域間の比較において, 地域の特性を示すのは, ある地域での摂取頻度がいくらかあり, 別地域では極端に低いといった食品に注目したほうがよいと考えられる。11) 摂取食品の記載の信頼性, 個々の食品の摂取頻度および摂取食品の食事回数の増加に伴う増加の様相は, 各地域における曲線はほぼ類似の曲線から, 十分見られ, お互い比較しうる確証であると考察した。12) 1回の食事および1日の平均摂取食品数, 低摂取頻度の食品数の摂取食品数に対する比率 (%) において, それぞれの地域でなんら差はなく, 日本の女子学生の食品数摂取状況は地域によって特性はなく, 摂取食品数の数の多さからして, 楽しい食生活に満ちていると結論づけた。