Effect of dietary sodium on fluid/electrolyte regulation during bed rest.

Background: A negative fluid balance during bed rest (BR) is accompanied by decreased plasma volume (PV) which contributes to cardiovascular deconditioning.

Hypothesis: We hypothesized that increasing dietary sodium while controlling fluid intake would increase plasma osmolality (POSM), stimulate fluid conserving hormones, and reduce fluid/electrolyte (F/E) losses during BR; conversely, decreasing dietary sodium would decrease POSM, suppress fluid conserving hormones, and increase F/E losses.

Methods: We controlled fluid intake (30 ml x kg(-1) x d(-1)) in 17 men who consumed either a 4.

Lack of adaptation to severe malnutrition in elderly patients.

Background & Aims: Sarcopenia is a common feature in the healthy elderly. However, little is known on age-related modifications of body composition in malnourished patients. The aims of this cross-sectional study were to evaluate the effects of aging per se on body composition and resting energy expenditure (REE) in malnourished patients.

Effect of steroids on energy expenditure and substrate oxidation in women with Crohn's disease.

Objective: Patients with Crohn's disease (CD) have increased energy expenditure and fat oxidation. Steroids, commonly used to treat flare-up of CD, induce weight gain. This study was designed to evaluate the effects of prednisone and budesonide on energy expenditure and substrate oxidation in patients with CD.

Lower-body negative-pressure exercise and bed-rest-mediated orthostatic intolerance.

Purpose: Supine, moderate exercise is ineffective in maintaining orthostatic tolerance after bed rest (BR). Our purpose was to test the hypothesis that adding an orthostatic stress during exercise would maintain orthostatic function after BR.

Methods: Seven healthy men completed duplicate 15-d 6 degrees head-down tilt BR using a crossover design.

Fatigue is associated with high circulating leptin levels in chronic hepatitis C.

Background And Aims: Fatigue is a frequent and disabling symptom reported by patients with chronic hepatitis C (CHC). Its mechanism is poorly understood. Recent attention has focused on the role of leptin and energy expenditure in CHC.

Virtual reality as a distraction intervention for older children receiving chemotherapy.

The purpose of this pilot study was to describe the perceived effectiveness and feasibility of using virtual reality (VR) as a distraction intervention for children, aged 10-17, receiving outpatient chemotherapy. Treatments for cancer are intensive and difficult to endure. Distraction interventions are effective because the individual concentrates on pleasant or interesting stimuli instead of focusing on unpleasant symptoms.

Role of skin blood flow and sweating rate in exercise thermoregulation after bed rest.

Two potential mechanisms, reduced skin blood flow (SBF) and sweating rate (SR), may be responsible for elevated intestinal temperature (T(in)) during exercise after bed rest and spaceflight. Seven men underwent 13 days of 6 degrees head-down bed rest. Pre- and post-bed rest, subjects completed supine submaximal cycle ergometry (20 min at 40% and 20 min at 65% of pre-bed rest supine peak exercise capacity) in a thermoneutral room.

Chemotherapy-induced nausea and vomiting.

Nausea and vomiting (N&V) is among the most distressing side effects of chemotherapy, despite the development of more efficacious antiemetic agents. As many as 60% of patients who receive cancer chemotherapy experience some degree of N&V. However, the actual incidence is difficult to determine with accuracy because of the variety of drugs, doses, and health conditions of the patients who receive cancer treatments.

Effect of age on substrate oxidation during total parenteral nutrition.

Objective: Parenteral nutrition is increasingly used in the elderly. Aging is accompanied by metabolic changes that can modify substrate use. We compared substrate oxidation during cyclic total parenteral nutrition (TPN) in elderly and middle-aged patients.

Invited review: gender issues related to spaceflight: a NASA perspective.

This minireview provides an overview of known and potential gender differences in physiological responses to spaceflight. The paper covers cardiovascular and exercise physiology, barophysiology and decompression sickness, renal stone risk, immunology, neurovestibular and sensorimotor function, nutrition, pharmacotherapeutics, and reproduction. Potential health and functional impacts associated with the various physiological changes during spaceflight are discussed, and areas needing additional research are highlighted.

From single site to societal belief: the impact of pediatric oncology nursing research.

This review describes the evolution of pediatric oncology nursing research over the past 25 years. It highlights practice-changing contributions from single-site studies and from multisite trials and discusses strategies for interdisciplinary collaboration. Technological advances that will alter the way in which studies are conducted and findings are disseminated will influence the future of nursing research.

Ageing and muscle: the effects of malnutrition, re-nutrition, and physical exercise.

Because of the metabolic changes caused by ageing, malnutrition is accompanied by a preferential loss of fat-free mass in the elderly, and it exaggerates the physiological loss of body cell mass, muscle mass and muscle function observed in the aged. Exercise training has positive anabolic effects even in the frail elderly, and may improve the effect of re-nutrition in malnourished elderly patients.

Outcome of patients treated with home enteral nutrition.

Background: The aims of this study were to prospectively analyze the 1-month mortality and long-term outcome of home enteral nutrition (HEN) patients in order to determine the benefits of this treatment.

Methods: Between 1990 and 1996, 417 patients, aged 64 +/- 25 years, were discharged on HEN and followed up until December 31, 1998, when outcome was assessed, which allowed us to determine survival probabilities and conditions associated with survival.

Results: The mean duration of HEN was 242 +/- 494 days, with a 24- to 103-month follow-up.

Total artificial nutrition is associated with major changes in the fecal flora.

Background: Animal studies have demonstrated dramatic changes in the intestinal flora during total enteral (TEN) or parenteral (TPN) nutrition.

Aim Of The Study: To assess the impact of TEN and TPN on human intestinal microflora.

Methods: Eight patients on fiber-free TEN, five patients on TPN, and ten controls were studied.

[Atrophic polychondritis associated with ulcerative colitis].

We report the case of a 46-year-old patient in whom ulcerative colitis had been diagnosed three years ago. He was admitted to the hospital for swelling of the nose. Clinical course and complementary exams led us to diagnose atrophic polychondritis.

Simulated shuttle egress: role of helmet visor position during approach and landing.

Background: We previously reported that carbon dioxide (CO2) rapidly accumulates in the helmet of the NASA Launch and Entry Suit (LES) during a simulated egress from the Space Shuttle following 6 min of visor-closed seated rest to simulate approach and landing. The purpose of this study was to determine if CO2 accumulation and walking time in the LES would be improved by helmet visor-open rather than visor-closed seated rest prior to the performance of the simulated egress.

Methods: Wearing the LES, 12 male subjects performed 4 laboratory egress simulations consisting of 6-min seated rest, 2-min stand, and 5-min walk at 1.

Activity of the leukocyte NADPH oxidase in whole neutrophils and cell-free neutrophil preparations stimulated with long-chain polyunsaturated fatty acids.

Fish oils are known for their anti-inflammatory effects. In this paper we investigated the influence of eicosapentaenoic acid and docosahexaenoic acid (omega-3 fatty acids), as well as docosapentaenoic acid, a metabolic product of omega-3 fatty acid metabolism, on O2(-)-production catalyzed by the NADPH oxidase in whole neutrophils and in a cell-free system consisting of neutrophil membranes and cytosol. As a standard we used arachidonic acid (an omega-6 fatty acid) found in a high proportion in the Western diet, and known as an effective activator of the oxidase in both systems.

Simulated shuttle egress: comparison of two Space Shuttle protective garments.

Background: In a previous study from our laboratory, we observed carbon dioxide (CO2) accumulation in the helmet of the NASA Launch and Entry Suit (LES) during a simulated emergency egress from the Space Shuttle. Of 12 subjects, 8 were unable to complete the egress simulation with a G-suit inflation pressure of 1.5 psi.

Maximal exercise as a countermeasure to orthostatic intolerance after spaceflight.

Unlabelled: Previous investigators have suggested that maximal exercise performed 24 h before the end of bed rest, a spaceflight analog, restores prebed rest plasma volume, baroreflex responses, and orthostatic tolerance.

Purpose: In this case report, we examined the effect of a similar exercise protocol 24 h before a Shuttle landing on the orthostatic responses of four crewmembers (EX) after spaceflights of 8-14 d. Four additional crewmembers (CON) served as controls and did not perform exercise during the final day of the flight.

Resting energy expenditure in chronic hepatitis C.

Background/aims: Hypermetabolism is considered to be of clinical interest in liver disease and in several chronic viral infections. Whether resting energy expenditure (REE) increases during chronic hepatitis C is not known. Our aims were: (a) to determine the metabolic state of patients with chronic hepatitis C, and (b) to evaluate the effects of interferon therapy on REE.

Activation of retinoic acid receptor alpha is sufficient for full induction of retinoid responses in SK-BR-3 and T47D human breast cancer cells.

Retinoid signaling via retinoic acid (RA) and retinoid X receptors (RARs and RXRs) regulates mammary epithelial cell growth and differentiation. Loss of RAR-beta might represent an early event during breast carcinogenesis. Higher differentiated, estrogen-dependent, estrogen receptor (ER)-positive (ER+) mammary carcinoma cells have been found to contain relatively high levels of RAR-alpha and to be responsive to retinoids, whereas most undifferentiated, estrogen-independent, ER-negative (ER-) cells are characterized by low RAR-alpha expression and by retinoid resistance.