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B L Rice

Publications and source records attributed to B L Rice.

12 recordsLinked to original sources

Nutritional status assessment in semiclosed environments: ground-based and space flight studies in humans.

Adequate nutrition is critical during long-term spaceflight, as is the ability to easily monitor dietary intake. A comprehensive nutritional status assessment profile was designed for use before, during and after flight. It included assessment of both dietary intake and biochemical markers of nutritional status. A spaceflight food-frequency questionnaire (FFQ) was developed to evaluate intake of key nutrients during spaceflight. The nutritional status assessment protocol was evaluated during two ground-based closed-chamber studies (60 and 91 d; n = 4/study), and was implemented for two astronauts during 4-mo stays on the Mir space station. Ground-based studies indicated that the FFQ, administered daily or weekly, adequately estimated intake of key nutrients. Chamber subjects maintained prechamber energy intake and body weight. Astronauts tended to eat 40--50% of WHO-predicted energy requirements, and lost >10% of preflight body mass. Serum ferritin levels were lower after the chamber stays, despite adequate iron intake. Red blood cell folate concentrations were increased after the chamber studies. Vitamin D stores were decreased by > 40% on chamber egress and after spaceflight. Mir crew members had decreased levels of most nutritional indices, but these are difficult to interpret given the insufficient energy intake and loss of body mass. Spaceflight food systems can provide adequate intake of macronutrients, although, as expected, micronutrient intake is a concern for any closed or semiclosed food system. These data demonstrate the utility and importance of nutritional status assessment during spaceflight and of the FFQ during extended-duration spaceflight.

Adult↗

Simulated microgravity [bed rest] has little influence on taste, odor or trigeminal sensitivity.

Anecdotal evidence suggests that astronauts' perceptions of foods in space flight may differ from their perceptions of the same foods on Earth. Fluid shifts toward the head experienced in space may alter the astronauts' sensitivity to odors and tastes, producing altered perceptions. Our objective was to determine whether head-down bed rest, which produces similar fluid shifts, would produce changes in sensitivity to taste, odor or trigeminal sensations. Six subjects were rested three times prior to bed rest, three times during bed rest and two times after bed rest to determine their threshold sensitivity to the odors isoamylbutyrate and menthone, the tastants sucrose, sodium chloride, citric acid, quinine and monosodium glutamate, and to capsaicin. Thresholds were measured using a modified staircase procedure. Self-reported congestion was also recorded at each test time. Thresholds for monosodium glutamate where slightly higher during bed rest. None of the other thresholds were altered by bed rest.

Adult↗

Calcium metabolism before, during, and after a 3-mo spaceflight: kinetic and biochemical changes.

The loss of bone during spaceflight is considered a physiological obstacle for the exploration of other planets. This report of calcium metabolism before, during, and after long-duration spaceflight extends results from Skylab missions in the 1970s. Biochemical and endocrine indexes of calcium and bone metabolism were measured together with calcium absorption, excretion, and bone turnover using stable isotopes. Studies were conducted before, during, and after flight in three male subjects. Subjects varied in physical activity, yet all lost weight during flight. During flight, calcium intake and absorption decreased up to 50%, urinary calcium excretion increased up to 50%, and bone resorption (determined by kinetics or bone markers) increased by over 50%. Osteocalcin and bone-specific alkaline phosphatase, markers of bone formation, increased after flight. Subjects lost approximately 250 mg bone calcium per day during flight and regained bone calcium at a slower rate of approximately 100 mg/day for up to 3 mo after landing. Further studies are required to determine the time course of changes in calcium homeostasis during flight to develop and assess countermeasures against flight-induced bone loss.

Calcium↗

Dietary studies in the joint US-Russian space program.

Metabolic experiments in the joint US-Russian space program involve analysis of food records, which include weighed foods, stable-isotope turnover, and biochemical samples collected before, during, and after the flights. This article describes the methods of monitoring dietary intake for this program.

Aerospace Medicine↗

Nutrition in space: lessons from the past applied to the future.

From the basic impact of nutrient intake on health maintenance to the psychosocial benefits of mealtime, the role of nutrition in space is evident. In this discussion, dietary intake data from three space programs, Apollo, Space Shuttle, and Skylab, are presented. Data examination reveals that energy and fluid intakes are almost always lower than predicted. Nutrition in space has many areas of impact, including provision of required nutrients and maintenance of endocrine, immune, and musculoskeletal systems. Long-duration missions will require quantitation of nutrient requirements for maintenance of health and protection against the effects of microgravity. Psychosocial aspects of nutrition will also be important for more productive missions and crew morale. Realization of the full role of nutrition during spaceflight is critical for the success of extended-duration missions. Research conducted to determine the impact of spaceflight on human physiology and subsequent nutritional requirements will also have direct and indirect applications in Earth-based nutrition research.

Diet↗

Distribution and correlates of waist-to-hip ratio in black adults: the Pitt County Study.

A 1988 community-based survey of 1,784 black adults aged 25-50 years in Pitt County, North Carolina, found mean waist-to-hip ratios of 0.890 for men and 0.852 for women. Based on guidelines from the US Department of Agriculture, 20% of the men and 76% of the women had an elevated waist-to-hip ratio. Sedentary behavior was associated with elevated waist-to-hip ratio in men, while a similar excess was associated with alcohol consumption in women. Weak, nonsignificant associations with waist-to-hip ratio were observed for smoking. Socioeconomic status was unrelated to waist-to-hip ratio in men, but it had a strong inverse relation for women.

Adipose Tissue↗

Prognostic factors associated with recurrence in clinical stage I adenocarcinoma of the endometrium.

Two hundred sixty-four consecutive patients with clinical stage I endometrial adenocarcinoma who underwent primary surgical therapy between July 1979 and August 1988 were followed prospectively and evaluated for disease recurrence for 8-112 months (mean 51.5). Thirty-three patients (12.5%) developed recurrence or died of disease. In univariate statistical analysis, prognostic factors significantly associated with disease recurrence were as follows: age (mean 68.6 years with versus 60.3 years without recurrence; P = .0001); histology (adenocarcinoma 8.8%, adenosquamous 35.7%, papillary 25%, clear-cell 57.1%; P less than .0001); tumor grade (grade 1, 7.7%, grade 2, 10.5%, grade 3, 36.1%; P less than .0001); depth of myometrial invasion (none 9.8%, less than one-half 7.4%, one-half or greater 29.6%; P = .0001); lymph node status (negative 8.3%, positive 47.6%; P less than .0001); non-nodal extrauterine disease spread (absent 11.0%, present 50%; P = .0003); peritoneal cytology (negative 9.4%, positive 26.3%; P = .004), and tumor size (2 cm or less 7%, greater than 2 cm 17.3%; P = .05). Cervical extension and uterine size had no significant effect on recurrence. Using multivariate analysis, grade 3 tumor (P = .002), advancing age (P = .004), lymph node metastasis (P = .006), and presence of extrauterine disease spread other than lymph node metastasis (P = .038) were the only variables significantly associated with disease recurrence or death. This study supports the new International Federation of Gynecology and Obstetrics surgical staging system for endometrial cancer.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗

Carbachol modulates GIP-mediated insulin release from rat pancreatic lobules in vitro.

Rat pancreatic lobules were used to investigate the interaction of gastric inhibitory polypeptide (GIP), carbachol, glucose, and an amino acid mixture on insulin secretion. At 5 mM glucose, GIP (1.1 ng/ml) did not augment insulin secretion in the presence or absence of carbachol (5 X 10(-5)M) during a 210-min incubation. However, at 11 mM glucose, GIP did augment insulin secretion in the presence (342.5 +/- 62.0 vs. 212.5 +/- 50.5 microU . ml-1 . mg tissue-1, mean +/- SE; P less than 0.01) but not the absence (217.0 +/- 45.5 vs. 205.8 +/- 35.0 microU . ml-1 . mg tissue-1) of carbachol. During subsequent 30-min incubations, GIP was increased to a supra-physiological concentration of 11 ng/ml and again augmented insulin secretion with (65.8 +/- 10.8 vs. 27.8 +/- 2.4 microU . ml-1 . mg tissue-1 . h-1; P less than 0.001) but not without (37.2 +/- 1.8 vs. 30.2 +/- 2 microU . ml-1 . mg-1 tissue-1 . h-1) carbachol present. This GIP-mediated insulin secretion was blocked by atropine (34.8 to 1.8 vs. 37.6 +/- 1.6 microU . ml-1 . mg tissue-1 . h-1). At amino acid concentrations of 21 and 211 mM, but not 2.1 mM, GIP augmented insulin release but again only with carbachol present. In conclusion, porcine GIP augments amino acid as well as glucose-mediated insulin secretion in vitro. Furthermore, this biological action is dependent on an, as yet, unidentified cholinergic mechanism. The pathophysiological significance of the neural-hormonal interaction deserves further investigation.

Amino Acids↗

Nutrition in space.

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Adaptation, Physiological↗