scholarly journals Effects of 21 days of bed rest, with or without artificial gravity, on nutritional status of humans

2009 ◽  
Vol 107 (1) ◽  
pp. 54-62 ◽  
Author(s):  
S. R. Zwart ◽  
G. E. Crawford ◽  
P. L. Gillman ◽  
G. Kala ◽  
A. S. Rodgers ◽  
...  
Keyword(s):  
Nutritional Status ◽  
Rest Period ◽  
Nutrient Status ◽  
Bed Rest ◽  
Blood Chemistry ◽  
Artificial Gravity ◽  
Blood Levels ◽  
Negative Effects ◽  
Vitamin Status ◽  
Β Carotene

Spaceflight and bed rest models of microgravity have profound effects on physiological systems, including the cardiovascular, musculoskeletal, and immune systems. These effects can be exacerbated by suboptimal nutrient status, and therefore it is critical to monitor nutritional status when evaluating countermeasures to mitigate negative effects of spaceflight. As part of a larger study to investigate the usefulness of artificial gravity as a countermeasure for musculoskeletal and cardiovascular deficits during bed rest, we tested the hypothesis that artificial gravity would have an effect on some aspects of nutritional status. Dietary intake was recorded daily before, during, and after 21 days of bed rest with artificial gravity ( n = 8) or bed rest alone ( n = 7). We examined body composition, hematology, general blood chemistry, markers of oxidative damage, and blood levels of selected vitamins and minerals before, during, and after the bed rest period. Several indicators of vitamin status changed in response to diet changes: serum α- and γ-tocopherol and urinary 4-pyridoxic acid decreased ( P < 0.001) and plasma β-carotene increased ( P < 0.001) in both groups during bed rest compared with before bed rest. A decrease in hematocrit ( P < 0.001) after bed rest was accompanied by a decrease in transferrin (P < 0.001), but transferrin receptors were not changed. These data provide evidence that artificial gravity itself does not negatively affect nutritional status during bed rest. Likewise, artificial gravity has no protective effect on nutritional status during bed rest.

scholarly journals Effects of artificial gravity during bed rest on bone metabolism in humans

2009 ◽  
Vol 107 (1) ◽  
pp. 47-53 ◽  
Author(s):  
S. M. Smith ◽  
S. R. Zwart ◽  
M. A. Heer ◽  
N. Baecker ◽  
H. J. Evans ◽  
...  
Keyword(s):  
Bone Metabolism ◽  
Bone Mineral ◽  
Rest Period ◽  
Bed Rest ◽  
Bone Alkaline Phosphatase ◽  
Artificial Gravity ◽  
Whole Body ◽  
Mineral Density ◽  
Microgravity Simulation ◽  
Before And After

We report results from a study designed to explore the utility of artificial gravity (AG) as a countermeasure to bone loss induced by microgravity simulation. After baseline testing, 15 male subjects underwent 21 days of 6° head-down bed rest to simulate the deconditioning associated with spaceflight. Eight of the subjects underwent 1 h of centrifugation (AG; 1 Gz at the heart, 2.5 Gz at the feet) each day for 21 days, whereas seven of the subjects served as untreated controls (Con). Blood and urine were collected before, during, and after bed rest for bone marker determinations. Bone mineral density (BMD) and bone mineral content (BMC) were determined by dual-energy X-ray absorptiometry and peripheral quantitative computerized tomography before and after bed rest. Urinary excretion of bone resorption markers increased during bed rest, but the AG and Con groups did not differ significantly. The same was true for serum C-telopeptide. During bed rest, bone alkaline phosphatase (ALP) and total ALP tended to be lower in the AG group ( P = 0.08, P = 0.09). Neither BMC nor BMD changed significantly from the pre-bed rest period in AG or Con groups, and the two groups were not significantly different. However, when AG and Con data were combined, there was a significant ( P < 0.05) effect of time for whole body total BMC and total hip and trochanter BMD. These data failed to demonstrate efficacy of this AG prescription to prevent the changes in bone metabolism observed during 3 wk of bed rest.

No effect of artificial gravity on lung function with exercise training during head-down bed rest

2015 ◽  
pp. 1-7
Author(s):  
Longxiang Su ◽  
Yinghua Guo ◽  
Yajuan Wang ◽  
Delong Wang ◽  
Changting Liu
Keyword(s):  
Lung Function ◽  
Pulse Rate ◽  
Vital Capacity ◽  
Pulmonary Ventilation ◽  
Bed Rest ◽  
Forced Expiratory Volume ◽  
Observation Time ◽  
Artificial Gravity ◽  
Postural Changes ◽  
Expiratory Flow

AbstractTo explore the effectiveness of microgravity simulated by head-down bed rest (HDBR) and artificial gravity (AG) with exercise on lung function. Twenty-four volunteers were randomly divided into control and exercise countermeasure (CM) groups for 96 h of 6° HDBR. Comparisons of pulse rate, pulse oxygen saturation (SpO2) and lung function were made between these two groups at 0, 24, 48, 72, 96 h. Compared with the sitting position, inspiratory capacity and respiratory reserve volume were significantly higher than before HDBR (0° position) (P&lt; 0.05). Vital capacity, expiratory reserve volume, forced vital capacity, forced expiratory volume in 1 s, forced inspiratory vital capacity, forced inspiratory volume in 1 s, forced expiratory flow at 25, 50 and 75%, maximal mid-expiratory flow and peak expiratory flow were all significantly lower than those before HDBR (P&lt; 0.05). Neither control nor CM groups showed significant differences in the pulse rate, SpO2, pulmonary volume and pulmonary ventilation function over the HDBR observation time. Postural changes can lead to variation in lung volume and ventilation function, but a HDBR model induced no changes in pulmonary function and therefore should not be used to study AG CMs.

Decreased Cysteine and Glutathione Levels: Possible Determinants of Liver Toxicity Risk in Ghanaian Subjects

1994 ◽  
Vol 22 (3) ◽  
pp. 171-176 ◽  
Author(s):  
N-A Ankrah ◽  
T Rikimaru ◽  
F A Ekuban ◽  
M M Addae
Keyword(s):  
Vitamin A ◽  
Liver Toxicity ◽  
Malonic Dialdehyde ◽  
Serum Levels ◽  
Blood Levels ◽  
Liver Inflammation ◽  
Body Tissues ◽  
Group 2 ◽  
Β Carotene ◽  
Group 1

Cysteine, methionine, vitamin A, β-carotene and glutathione (GSH) are known to protect body tissues against oxidative damage and inflammation but their value as protection against liver inflammation in tropical areas has received little attention. Blood levels of these nutrients were measured in Ghanaian volunteers with (Group 2) or without (Group 1) increased lipid peroxidation and signs of liver inflammation, as indicated by blood malonic dialdehyde, serum α1-antitrypsin and triglyceride levels, and the α1-acid glycoprotein: pre-albumin ratio. Serum levels of cysteine and blood glutathione were significantly lower ( P < 0.02) in group 2 than in group 1 volunteers. In contrast, serum levels of methionine, vitamin A and β-carotene were similar in both groups. Deficits in cysteine and glutathione may increase the risk of liver toxicity from oxidants in Ghanaians.

scholarly journals Grade of esophageal cancer and nutritional status impact on postsurgery outcomes

2010 ◽  
Vol 47 (4) ◽  
pp. 348-353 ◽  
Author(s):  
Flávia Andréia Marin ◽  
Vânia Cristina Lamônica-Garcia ◽  
Maria Aparecida Coelho de Arruda Henry ◽  
Roberto Carlos Burini
Keyword(s):  
Body Mass Index ◽  
Nutritional Status ◽  
Disease Severity ◽  
Body Mass ◽  
Disease Onset ◽  
Body Weight Loss ◽  
Blood Chemistry ◽  
Palliative Surgery ◽  
Postsurgical Complications ◽  
Complications And Mortality

CONTEXT: Undernutrition is a well known underlying cause in both disease onset and outcome. OBJECTIVE: To associate disease severity with pre surgical nutritional status, the main postsurgical complications, and mortality in esophagus cancer patients. METHOD: Retrospective data from 100 patients (38-81 years old, 85% males) who had undergone esophagectomy (G1/n = 25) or gastro/jejunostomy (G2/n = 75) between 1995 and 2004. Data included clinical, endoscopic, histological (TNM-UICC), dietary, anthropometric, blood chemistry, and postsurgical (>30 days) complications and mortality. Surgical groups were compared by Student's test and existing associations between variables by either c² or Fisher exact tests with P = 0.05. RESULTS: The studied sample was predominantly male (85%), white (80%), smokers and alcoholics (95%), dysphagics (95%) mostly presenting body weight loss before cancer diagnosis (78%). TNM III and IV predominated over I and II, associated (P<0.005) with higher body mass index and hypoalbuminemia (<3.5 mg/dL) frequency. Esophagic obstructions (n = 77) were associated (P = 0.002) with lower body mass index (kg/m²). Postsurgical complications were more common in G1 (69.2%) than G2, predominantly with infections in G2 (80%) and pleura-pulmonary in G1 (61%). Body mass index and lower lymphocyte counts were associated with early infections and postsurgical complications in G2. Plasma albumin levels were lower in this group than G1, and were associated with postsurgical complications and mortality whereas lower lymphocyte counts was associated with mortality in G1. CONCLUSIONS: Disease severity (or late diagnosis) is associated with poor nutritional status and palliative surgery which lead to more complicated postsurgery outcome and mortality. Early diagnosis and nutritional intervention are the recommended actions.

Is Combination Therapy for Encopresis Nutritionally Safe?

PEDIATRICS ◽  
1993 ◽  
Vol 91 (3) ◽  
pp. 591-594
Author(s):  
H. Juhling McClung ◽  
Linda J. Boyne ◽  
Thomas Linsheid ◽  
Leo A. Heitlinger ◽  
Robert D. Murray ◽  
...  
Keyword(s):  
Nutritional Status ◽  
Blood Chemistry ◽  
Fiber Intake ◽  
High Fiber ◽  
Dietary Fiber Intake ◽  
Movement Frequency ◽  
Before And After ◽  
Bowel Movement Frequency ◽  
Fecal Soiling ◽  
Bowel Decompression

Chronic constipation accounts for 3% to 5% of pediatric primary care outpatient visits. The most severely affected of this group develop a flaccid colon insensitive to distention, and encopresis. Laxatives and lubricants have been the standard therapeutic agents during the bowel decompression phase of encopretic therapy. Fiber has been the cornerstone of maintenance programs. Each of these agents is accompanied by considerable anxiety in the lay literature. This study evaluates the safety of combined high-fiber, laxative, and lubricant therapy on bowel movement frequency, fecal soiling, and nutritional status over a 6-month period. Blood chemistry values, dietary fiber intake, defecation pattern, and a psychological profile were evaluated before and after the 6-month study. Biochemical and anthropometric indicators of nutritional status were not adversely affected by the therapy. Seventy-five percent of the children were able to remain free of soiling and the remaining 4 of 16 had soiling episodes reduced to a frequency of less than once a week. This study confirms that children with encopresis can respond to a combined program of increased fiber intake, laxatives, and mineral oil following a complete bowel cleanout, without experiencing deleterious effects.

scholarly journals Dust Pollution Reduced Stomatal Conductance and Photosynthetic Pigments of Selected Medicinal Plants Growing at Lokpa Ukwu Quarry Site in Abia State, Nigeria

2020 ◽  
pp. 1-11
Author(s):  
C. E. Ogbonna ◽  
F. I. Nwafor ◽  
N. O. Nweze
Keyword(s):  
Stomatal Conductance ◽  
Medicinal Plants ◽  
Photosynthetic Pigments ◽  
Total Chlorophyll ◽  
Negative Effects ◽  
Dust Pollution ◽  
Standard Procedures ◽  
Maximum Conductance ◽  
Clearing Method ◽  
Β Carotene

Aims: We investigated the influence of dust pollution on stomatal conductance and photosynthetic pigments in some medicinal plants growing at Lokpa Ukwu quarry site, Abia State, Nigeria. Place and Duration of Study: Samples were collected from Lokpa Ukwu, Abia State while laboratory analyses were carried out in the Department of Pharmacognosy and Environmental Medicines, University of Nigeria, Nsukka between February and April, 2019. Methodology: A total of nine (9) plants were sampled for the study. Leaf epidermises were prepared by clearing method and stomata were observed and studied quantitatively. Stomatal conductance was estimated from the anatomical variables following standard procedures. Total chlorophyll and β-carotene contents were also analysed and compared with control groups. Results: We observed some physiological changes in the plants from dust-polluted site such as stretched epidermal cells, deformed stomata and plasmolysed guard cells. It reduced the potential conductance indices (PCI) of the plants by 87.4% in Aspilia africana and 67% in Chromolaena odorata. The least reduction in PCI was observed in Celosia trigyna (7.2%). Operating conductance (gop) and maximum conductance (gmax) were reduced by 69.2% and 72.3% in C. odorata and A. africana respectively. Celosia trigyna was least affected with percentage reductions of 18.3% and 1.4% for gop and gmax respectively. Reduction in PCI and gmax followed the order: C. trigyna ˂ C. papaya ˂ P. discoideus ˂ D. oliveri ˂ T. rhomboidea ˂ T. orientalis ˂ V. doniana ˂ C. odorata ˂ A. africana. Total chlorophyll and β-carotene contents were reduced the most in V. doniana (45.73%) and C. odorata (40.31%) respectively and least reduced in T. orientalis by 19.54% and 13.24% respectively. Conclusion: Our findings validate previous reports of negative effects of dust pollution from quarry industries on both humans and plants alike.

scholarly journals Head-down tilt bed rest with or without artificial gravity is not associated with motor unit remodeling

2020 ◽  
Vol 120 (11) ◽  
pp. 2407-2415 ◽  
Author(s):  
Julia Attias ◽  
Andrea Grassi ◽  
Alessandra Bosutti ◽  
Bergita Ganse ◽  
Hans Degens ◽  
...  
Keyword(s):  
Motor Unit ◽  
Compound Muscle Action Potential ◽  
Bed Rest ◽  
Artificial Gravity ◽  
Whole Body ◽  
Healthy Individuals ◽  
Long Duration ◽  
Muscle Action Potential ◽  
Abductor Digiti Minimi ◽  
Healthy Participants

Abstract Purpose The objective of this study was to assess whether artificial gravity attenuates any long-duration head-down 60 bed rest (HDBR)-induced alterations in motor unit (MU) properties. Methods Twenty-four healthy participants (16 men; 8 women; 26–54 years) underwent 60-day HDBR with (n = 16) or without (n = 8) 30 min artificial gravity daily induced by whole-body centrifugation. Compound muscle action potential (CMAP), MU number (MUNIX) and MU size (MUSIX) were estimated using the method of Motor Unit Number Index in the Abductor digiti minimi and tibialis anterior muscles 5 days before (BDC-5), and during day 4 (HDT4) and 59 (HDT59) of HDBR. Results The CMAP, MUNIX, and MUSIX at baseline did not change significantly in either muscle, irrespective of the intervention (p > 0.05). Across groups, there were no significant differences in any variable during HDBR, compared to BDC-5. Conclusion Sixty days of HDBR with or without artificial gravity does not induce alterations in motor unit number and size in the ADM or TA muscles in healthy individuals.

Cognitive Training Diminishes Negative Effects Of Simulated Microgravity During Bed Rest On Brain Electro-cortical Activity

2014 ◽  
Vol 46 ◽  
pp. 281
Author(s):  
Uros Marusic ◽  
Romain Meeusen ◽  
Kevin De Pauw ◽  
Kristel Knaepen ◽  
Rado Pisot ◽  
...  
Keyword(s):  
Cognitive Training ◽  
Simulated Microgravity ◽  
Bed Rest ◽  
Cortical Activity ◽  
Negative Effects

scholarly journals Improving Dietary Protein Quality Reduces the Negative Effects of Physical Inactivity on Body Composition and Muscle Function

2019 ◽  
Vol 74 (10) ◽  
pp. 1605-1611 ◽  
Author(s):  
Emily J Arentson-Lantz ◽  
Elfego Galvan ◽  
Jennifer Ellison ◽  
Adam Wacher ◽  
Douglas Paddon-Jones
Keyword(s):  
Body Composition ◽  
Blood Glucose ◽  
G Protein ◽  
Dietary Protein ◽  
Physical Inactivity ◽  
Protein Quality ◽  
Bed Rest ◽  
Peak Torque ◽  
Knee Extension ◽  
Negative Effects

Abstract Background Brief periods of physical inactivity can compromise muscle health. Increasing dietary protein intake is potentially beneficial but complicated by difficulties reconciling anabolic potential with a realistic food volume and energy intake. We sought to determine whether increasing dietary protein quality could reduce the negative effects of physical inactivity. Methods Twenty healthy, older men and women completed 7 days of bed rest followed by 5 days of rehabilitation. Volunteers consumed a mixed macronutrient diet (MIXED: N = 10; 68 ± 2 years; 1,722 ± 29 kcal/day; 0.97 ± 0.01 g protein/kg/day) or an isoenergetic, whey-augmented, higher protein quality diet (WHEY: N = 10; 69 ± 1 years; 1,706 ± 23 kcal/day; 0.90 ± 0.01 g protein/kg/day). Outcomes included body composition, blood glucose, insulin, and a battery of physical function tests. Results During bed rest, both groups experienced a 20% reduction in knee extension peak torque (p < .05). The WHEY diet partially protected leg lean mass (−1,035 vs. −680 ± 138 g, MIXED vs. WHEY; p = .08) and contributed to a greater loss of body fat (−90 vs. −233 ± 152 g, MIXED vs. WHEY; p < .05). Following rehabilitation, knee extension peak torque in the WHEY group fully recovered (−10.0 vs. 2.2 ± 4.1 Nm, MIXED vs. WHEY; p = .05). Blood glucose, insulin, aerobic capacity, and Short Physical Performance Battery (SPPB) changes were similar in both dietary conditions (p > .05). Conclusions Improving protein quality without increasing total energy intake has the potential to partially counter some of the negative effects of bed rest in older adults.

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