Energy and nutrient intakes of Okinawan centenarians.

Energy and nutrient requirements of younger people have been well studied, unlike that of centenarians. The average life span of the Japanese is the longest in the world, and the population of the very aged is rapidly growing. In addition, the average life span of Okinawan people is the longest in all of Japan. Their food habits also differ from other parts of Japan. To obtain basic dietary information, we surveyed 21 centenarians in Okinawa (17 women and 4 men). The dietary survey was done by one 24 h recall method, as was done for centenarians living throughout Japan (3). The energy intake of the Okinawan centenarians living at home was about 1,100 kcal/day for both sexes, which was similar to that of centenarians throughout Japan. Energy, some nutrient intakes and food consumption pattern (in terms of food groups) were different from those of the centenarians throughout Japan. We also measured their heights, weights, hematological values and activities of daily living (ADL). Comparison between the nutrient intakes and the recommended dietary allowances (RDAs) estimated for the centenarians showed that the estimated RDA of energy for the Okinawan centenarians might be less than their actual intakes.

Effect of egg white on serum cholesterol concentration in young women.

In a previous study we observed favorable effects of egg white on serum lipids in rats and mice. The present study was designed to elucidate these effects in 24 female university students with moderate hypercholesterolemia. About 30% of total protein was supplied with egg white, tofu or cheese. The experiment was conducted for a complete menstruation cycle of each subject. Lipid intake was about 30% of total energy intake. The energy intake of each subject was constant throughout the experiment. Body weight was measured every morning. Daily activity was measured by a pedometer. Blood was withdrawn after an overnight fast on the first, 15th and last days and serum lipids were measured. Body weight was measured every morning. Daily activity was measured by a pedometer. Blood was withdrawn after an overnight fast on the first, 15th and last days and serum lipids were measured. Body weight and daily activity were maintained in all the groups throughout the experiment. The egg white group showed a similar decrease in the total cholesterol (Total-C) concentration but a greater increase of high-density lipoprotein cholesterol (HDL-C) concentration as compared to the tofu group and a greater decrease in Total-C and low-density lipoprotein cholesterol (LDL-C) concentrations and a greater increase in the HDL-C concentration as compared to the cheese group (p < 0.05). The results indicate the favorable effects of egg white in the control of hypercholesterolemia.

Effect of a glutamine-supplemented diet on response to methicillin-resistant Staphylococcus aureus infection in mice.

The following study was undertaken to determine whether dietary supplementation with glutamine can be used to modulate the immune response following challenge with methicillin-resistant Staphylococcus aureus (MRSA) organisms in mice. Thirty BALB/c female mice were randomized into 3 groups: group A (n = 10) were fed 20% casein diet (control), whereas the mice in Groups B (n = 10) and C (n = 10) were given 20% casein diet supplemented with 2 and 4% glutamine, respectively. The diets were made isonitrogenous by glycine and alanine supplementation. On the 10th day on these treatments, each mouse was challenged intravenously with 2 x 10(8) colony-forming units (CFU)/ml of MRSA organisms and mortality was noted for 20 days. The survival rate in Group A (20%) tended to be lower than the rates in Group B (40%), and Group C (70%). CFU values of spleen and kidney of the surviving mice 20 days post challenge were not different among the three groups (p < 0.05). The present results suggest that dietary glutamine supplementation may be effective as a nutritional immunomodulator for the recovery from MRSA infection.

Protection of BALB/c mice against methicillin-resistant Staphylococcus aureus infection by intraperitoneal administration of nucleoside-nucleotide mixture.

The effect of intraperitoneally administered nucleic acid components (nucleoside-nucleotide mixture) on the recovery from methicillin-resistant Staphylococcus aureus (MRSA) strain 8985N infection was studied in mice. Two experiments were conducted in which BALB/c mice were fed a nucleotide-free 20% casein diet for 30 days. On the 10th day, the mice were inoculated intravenously with viable MRSA organisms. The mice were intraperitoneally administered nucleoside-nucleotide mixture or saline (control) daily from the onset of the experiment (experiment 1) or from the day of inoculation (experiment 2). The survival rate in the nucleoside-nucleotide group in experiment 1 (70%) was significantly higher than that in the saline group (20%) (p < 0.05). In experiment 2, the survival rate in the nucleoside-nucleotide group (55%) tended to be higher than that in the saline group (36%) without statistically significant difference; furthermore, in the surviving mice, the viable MRSA organisms recovered from the spleen and the kidney were fewer in the former group than in the latter group (p < 0.05). The studies showed that the intraperitoneal administration either before or after the MRSA challenge of the nucleoside-nucleotide mixture was effective for the recovery of the mice from the infection.

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)

Growth and flagellation of Vibrio fischeri during initiation of the sepiolid squid light organ symbiosis.

A pure culture of the luminous bacterium Vibrio fischeri is maintained in the light-emitting organ of the sepiolid squid Euprymna scolopes. When the juvenile squid emerges from its egg it is symbiont-free and, because bioluminescence is part of an anti-predatory behavior, therefore must obtain a bacterial inoculum from the surrounding environment. We document here the kinetics of the process by which newly hatched juvenile squids become infected by symbiosis-competent V. fischeri. When placed in seawater containing as few as 240 colony-forming-units (CFU) per ml, the juvenile became detectably bioluminescent within a few hours. Colonization of the nascent light organ was initiated with as few as 1 to 10 bacteria, which rapidly began to grow at an exponential rate until they reached a population size of approximately 10(5) cells by 12 h after the initial infection. Subsequently, the number of bacteria in the established symbiosis was maintained essentially constant by a combination of both a > 20-fold reduction in bacterial growth rate, and an expulsion of excess bacteria into the surrounding seawater. While V. fischeri cells are normally flagellated and motile, these bacteria did not elaborate these appendages once the symbiosis was established; however, they quickly began to synthesize flagella when they were removed from the light organ environment. Thus, two important biological characteristics, growth rate and flagellation, were modulated during establishment of the association, perhaps as part of a coordinated series of symbiotic responses.

Comparative effect of casein and soybean protein isolate on body fat accumulation in adult rats.

The effect of dietary protein on the body fat accumulation was studied in rats. Adult rats weighing about 300 g were fed 21% protein (casein or soybean protein isolate) and 5% oil diets by pair-feeding for 65 days in Experiment 1. In Experiment 2, only protein and oil contents were changed, 25 and 10%, respectively. Final body weights of the two dietary groups were similar in both experiments, especially in Experiment 2. Total body fat was slightly lower in the soybean protein diet group than in the casein diet group in Experiment 2, only when it was expressed as the percentage against body weight. However, intra-abdominal fat was significantly lower in the soybean protein diet groups than in the casein diet groups in both experiments. Serum lipid levels were greatly lower in the soybean protein diet group than in the casein diet group in Experiment 2 (the data were not available in Experiment 1). The results suggest that dietary soybean protein has the effect to lower the intra-abdominal fat accumulation as compared with casein.

Effect of intraperitoneally administered nucleoside-nucleotide on the recovery from methicillin-resistant Staphylococcus aureus strain 8985N infection in mice.

The effect of intraperitoneally administered nucleoside-nucleotide on the recovery from methicillin-resistant Staphylococcus aureus (MRSA) strain 8985N infection was studied in mice. Mice fed nucleic acid-free 20% casein diet were administered intraperitoneally with a nucleoside-nucleotide mixture or with saline (control group) daily for 30 days. On the tenth day on this treatment, mice were challenged with the bacteria. The survival rates were 25% and 72% for the control and nucleoside-nucleotide groups, respectively. The recovery of the survived mice from the infection was confirmed by the increment of body weight and the reduction of the bacteria in the organs. The results show the effectiveness of the intraperitoneal administration of the nucleoside-nucleotide mixture for the recovery from the MRSA strain 8985N infection in mice.