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V Frattali

Publications and source records attributed to V Frattali.

At least 19 recordsLinked to original sources

The new reference daily intakes: for better or for worse?

The introduction of the RDIs was well intentioned. However, there are scientific uncertainties and reasons for concerns about the proposed new nutrition standards. Adoption of the RDIs will inevitably lead to reduced intakes of critically important vitamins and minerals, will make it more difficult for members of nutritionally vulnerable groups to meet their nutrient needs, and will have undesirable effects on the health of the most needy by altering nutrition priorities and programs in this country. National nutrition standards remain with us for a long time. The U.S. RDAs have been in place for 18 years; any new standards need to be sound enough and safe enough to last as long. The proposed RDIs are clearly not of this caliber.

Eating↗

Interdependence of decompression sickness and plasma enzymes on dive profile and vitamin B-6 status.

The mortality rate due to decompression injury was found to be significantly greater in a rat population with a mild vitamin B-6 deficiency, compared to an adequately fed control group, when subjected to a bends-producing N2-O2 dive. Relative post-dive changes in lactate dehydrogenase, creatine phosphokinase, and transaminase levels in plasma do not appear to be sufficiently different to allow a ready distinction in the degree of susceptibility of one nutritionally defined population from the other.

Alanine Transaminase↗

Hana kai ii: a 17-day dry saturation dive at 18.6 ATA. II. Energy balance.

Since previous saturation dives have caused loss of body weight despite apparently adequate-to-high food intake, a complete study of energy balance was undertaken during the saturation dive Hana Kai II. Over a 30-day period in the hyperbaric chamber (3 days of predive control, 1 day of compression, 16 days at 18.6 ATA, 7 days of decompression, and 3 days of postdive control), all food, urine, and feces for five men were analyzed by bomb calorimetry; 24-h energy expenditure (M) was measured from continuous VO2, VCO2, and urine N. Body weight was taken daily; body composition was assessed from density, total body water, and skinfold thickness. Food intake was high throughout the 30 days (about 3500 kcal/day) while fecal and urinary losses were a normal 6-8% of intake. Energy expenditure was increased a little by the hyperbaric condition, but averaged only 2431 kcal/day for the 30 days and yet there was an average loss of adipose tissue of 0.8 kg for each man for the entire period. Nitrogen balance was positive. There was no evidence of heat gain or loss. The energy balance, total fuel compared with energy expenditure, required an additional 919 kcal/man-day for 30 days, an unidentified term which is not measured by conventional techniques.

Adult↗

Hana kai ii: a 17-day dry saturation dive at 18.6 ATA. III. Body fluid balance.

Comprehensive studies on body fluid balance on 5 divers were conducted during the Hana Kai II dive (17 days at 18.6 ATA and 7 days of decompression). Daily urine flow increased from about 2000 ml at 1 ATA to 2600 ml at 18.6 ATA, at 31 degrees C. This diuresis was accompanied by a reduction in urine osmolality (from 650 to 500 mOsm) and a slight increase in osmolal clearance. Endogenous creatinine clearance remained at about 173 ml/min throughout the dive. Despite such a sustained diuresis, neither daily water intake nor total body water volume changed significantly. The plasma renin activity changed little, while both plasma aldosterone concentration and urinary aldosterone excretion increased significantly during the first week at 18.6 ATA. The plasma prolactin concentration showed a significant decrease during the first 3 days at 18.6 ATA. The daily excretion of antidiuretic hormone (ADH) decreased significantly (by 40%) 4 days after compression and remained low throughout the rest of the dive. Insensible waterloss at 18.6 ATA was 35% lower than that at 1 ATA. It is suggested that the observed hyperbaric diuresis is due primarily to suppression of ADH as a result of suppression of insensible water loss.

Aldosterone↗

Ascorbic acid changes in cultured rabbit lenses after microwave irradiation.

Whole body exposure of rabbits to microwave radiation causes a decrease in ascorbic acid in the lens. In our study, rabbit lenses maintained in culture medium (37 degrees C) were exposed to either pulsed or continuous wave S-band radiation for 10-15 min at power densities between 0 and 200 mW/cm-2. Total ascorbic acid was measured in selected lenses 1-3 days after irradiation. The temperature of the culture medium was measured during irradiation. Matched control lenses were exposed to similar time-temperature environments, but without microwave irradiation. Ascorbic acid decreased significantly in lenses exposed to microwave radiation. No differences were found, however, between irradiated and control lenses subjected to identical time-temperature conditions. At a given average power density, the time-temperature variation was independent of modulation. A decrease in ascorbic acid is apparently a direct thermal effect of microwave radiation in rabbit lens culture.

Animals↗

Supportive evidence for altered platelet function in the dived rat.

A study was conducted on the changes in platelet function and platelet count in the Sprague-Dawley rat induced by a bends-producing N2-O2 compression-decompression cycle. In those instances where mild to moderate cases of decompression sickness were produced, a decrease in platelet reactivity to ADP-induced aggregation occurred immediately postdive along with an increase in inhibition of aggregation by prostaglandin E1. Both effects returned to control levels 24 hours postdive. In moderately affected animals, platelet counts were lower than normal 24 hours postdive but were similar to control values 72 hours postdive. These results tend to support current hypotheses regarding the etiological relationship between disseminated intravascular coagulation and decompression sickness as a function of bubble nucleation.

Adenosine Diphosphate↗

Effect of hyperbaric helium on vitamin uptake and utilization by micro-organisms.

Growth responses under hyperbaric helium of various procaryotic micro-organisms to graded levels of six water-soluble vitamins were measured. Vitamins included: thiamin, riboflavin, niacin, pantothenic acid, biotin, and folic acid (folacin). Growth response of each organism under hyperbaric helium was compared with that under 80% He-20% O2 and other He-O2 gas mixtures at atmospheric pressure, and with response in air at atmospheric pressure. For five of the six vitamins, no differences in response were observed. Growth response of Streptococcus faecalis to growth-limiting concentrations of folic acid was depressed during cultivation under He-O2 at 69 ATA. It is concluded that growth response of the organism is repressed by hyperbaric helium as a result of interference with uptake or utilization of the vitamin.

Animals↗