Intracellular Water Research Articles

ПРИМЕНЕНИЕ МЕТОДА ЯМР C ПАРАМАГНИТНЫМ ДОПИНГОМ ДЛЯ ОЦЕНКИ АПОПЛАСТНОГО ПЕРЕНОСА ВОДЫ В КОРНЯХ ИНТАКТНЫХ РАСТЕНИЙ ПРИ ДЕЙСТВИИ АБИОТИЧЕСКИХ СТРЕССОВ

In this work, the methodological approach based on low-field NMR using the GdDTPA paramagnetic complex for the qualitative assessment of water transport along the apoplastic (extracellular) pathway in the roots of intact wheat plants is proposed. This approach consists in measuring the spin-spin relaxation times of the water magnetization in the roots during simultaneous incubation of the roots in a solution of the paramagnetic Gd-DTPA complex and the impact of a stress factor on the plants. During root incubation, this complex spreads only along the root apoplast system and shortens the apoplast water relaxation times. GdDTPA does not penetrate into the cells and, accordingly, does not change the intracellular water relaxation times. Thus, the rate of decrease in the relaxation times of the magnetization of apoplast water, which directly depends on the intensity of water transfer through the apoplast, can be used to determine the relative contribution of water transfer through the root apoplast during stress exposure. A twofold increase in the concentration of carbon dioxide in the aerial parts of plants was used as an abiotic factor presumably influencing the transfer of water along the root apoplast. Using this methodological approach, it was shown that increase in the CO2 concentration in the leaf zone of wheat plants to 800 ppm leads to decrease in the rate of water transfer through the root apoplast by 2–2.5 times compared with the control at ambient CO2 concentration of 400 ppm.

QCM sensor provides insight into the role of pivotal ions in cellular regulatory volume decrease.

All vertebrate cells generally self-regulate for sustaining homeostasis and cell functions. As a major regulatory mechanism, regulatory volume decrease (RVD) occurs in hypotonicity-induced cell swelling, and then shrinking by the efflux of intracellular osmolytes and water, in which the ions K+, Cl-, and Ca2+ play a key role in the RVD process. We observed that these pivotal ions could result in novel RVD behaviors under repeatedly hypotonic stimulation. However, there is a lack of valid means for assessing the effect of pivotal ions on RVD. In this work, we proposed an effective measurement process based on a quartz crystal microbalance (QCM) combined with cell function of RVD for revealing acute variations in cell volume regulation induced by the pivotal ions. A QCM sensor was implemented by adhering MCF-7 cells to a poly-l-lysine-modified gold chip and cyclic stimulation with hypotonic NaCl medium, in which a frequency shift (Δf) showed the superior feasibility of the technique in exhibiting RVD behaviors. With the increase in the number of cycles, the RVD values decreased progressively under three stimulation cycles with hypotonic NaCl alone. Compared with the first cycle, the RVD level in the second and third cycles declined by 60.7±1.7% and 82.1±1.6% (n=3), respectively; conversely, it recovered in NaCl-KCl solution, but was significantly enhanced by 52.2±0.8% in NaCl-CaCl2 solution. Moreover, the inhibition of chloride channels to block Cl- efflux also decreased the RVD level by 56.2±3.0%. The results indicate that these ions (K+, Cl-, Ca2+) are all able to affect the function of RVD, among which intracellular Cl- depletion reduced RVD during measurement, but which recovered with K+ supplement, and Ca2+ enhanced RVD due to activation of ion channels. Therefore, this work provides a comprehensive assessment of cellular behavior and offers an innovative method for gaining insight into cellular functions and mechanisms. A novel strategy was conducted by integrating a quartz crystal microbalance (QCM) with the function of cell volume regulation for analyzing the role of the pivotal ions ( K+, Cl-, Ca2+) in NaCl media on the behaviors of regulatory cell volume decrease (RVD).

Translocation and Utilization Mechanisms of Leaf Intracellular Water in Karst Plants Orychophragmus violaceus (L.) O. E. Schulz and Brassica napus L.

Orychophragmus violaceus (L.) O. E. Schulz adapts to karst environments through a variety of adaptability mechanisms. However, the leaf intracellular water translocation and utilization mechanism is still unknown. This study hypothesizes that plants adapt to dehydration by synergistically adjusting the leaf anatomy, cell elasticity and intracellular water translocation. Leaf structure, elastic modulus (Em), physiological capacitance (CP), impedance (Z), water potential (ΨL), leaf tensity (LT) and chlorophyll fluorescence parameters of the detached leaves in plants of O. violaceus and Brassica napus L. were measured at each water loss time (0, 1, 2, 3, 4 and 5 h). The uniform leaves were randomly selected from five different plants for each species. The cell vacuole volume and translocation resistance of intracellular water could be represented by the electrophysiological parameters, such as CP and Z. The results indicated that timely shrinkage of O. violaceus leaves and mesophyll cells together with the increased water translocation resistance retained the intracellular water and maintained the turgor pressure. Water within sponge parenchyma could also be translocated into palisade parenchyma. The PSII reaction center was kept stable, and the photosynthetic activity of O. violaceus was clearly inhibited at 3 h. Palisade parenchyma of B. napus leaves increased quickly to improve the intercellular water translocation due to the strong cell stiffness. Gradually increasing intracellular water translocation resistance and recovery of the cell elasticity slowed down the leaf water loss, which, however, could not timely stop the damage on the PSII reaction center and the photochemical efficiency. The photochemical efficiency was seriously inhibited at 4 h and 5 h. The response mechanism of intracellular water to dehydration can be investigated with the help of leaf electrophysiological traits. However, the direct determination of plant drought resistance using electrophysiological information can still not be realized at present and needs further research.

Exploring the hydration promotion and cooking quality improvement of adlay seed by high hydrostatic pressure

Adlay (Coix lacryma-jobi L. var. ma-yuen Stapf), a minor cereal, has long been consumed as both a food and a medicine. However, adlay seeds have a dense episperm and its tissue is hard, which makes water absorption difficult. High hydrostatic pressure (HHP), as a non-thermal processing technology, enables batch hydration of grains in a short time. In this work, the hydration promotion and cooking quality improvement of adlay seeds by HHP (300–600 MPa) were investigated. Results showed that HHP pretreatment promoted seed hydration by inducing cracks in the seed cross-section and disrupting the cell wall and ventral groove structure. HHP pretreatment increased the proportion of intracellular water and unbound water in the cooked adlay seeds, facilitated water infiltration from the seed grooves and increased the hydration rate by creating a water gradient between the soak water and seeds. After applying HHP during soaking, the cooking time of adlay seeds was reduced, and the cooked adlay seeds were softer, brighter in color.

Diurnal Variation in Transport and Use of Intracellular Leaf Water and Related Photosynthesis in Three Karst Plants

Except for transpired water, the intracellular water stored in leaves accounts for only 1–3% of the water absorbed by roots. Understanding water transport and use, as well as the related photosynthetic response, helps with determining plant water status and improving the revegetation efficiency in fragile karst habitats. In this study, we conducted experiments on 8 year old naturally growing plants of Coriaria nepalensis Wall., Broussonetia papyrifera (L.) Vent., and Elaeocarpus decipiens Hemsl. in karst areas. We determined the diurnal variations in leaf electrophysiology, water potential, gas exchange, and chlorophyll fluorescence parameters. The results indicated that C. nepalensis plants maintained a high photosynthetic rate, with a high root water uptake ability and leaf intracellular water-holding capacity (LIWHC). The stomata quickly closed to conserve water within cells and protect the photosynthetic structure. B. papyrifera maintained stable intracellular water transport rate (LIWTR), and the photosynthetic efficiency was increased with increasing intracellular water-use efficiency (LIWUE). B. papyrifera also maintained its photosynthesis by efficiently using the transpired water when the LIWHC was increased. The inter- and intracellular water in the leaves of E. decipiens remained stable, which could be attributed to the leathery leaves and its high water-holding capacity. The photosynthesis of E. decipiens was low and stable. Compared with the high photosynthesis, high transpiration, and low instantaneous water-use efficiency (WUEi) pattern in C. nepalensis plants, E. decipiens plants exhibited low photosynthesis, low transpiration, and low WUEi, whereas B. papyrifera plants presented high photosynthesis, low transpiration, and high WUEi. Plants in karst regions change their transport and use of intracellular leaf water to regulate the photosynthetic performance, which differs among different plant species.

Matching Body Composition Confirms Decreased Phase Angle among Diabetics Compared to Controls

Background: Diabetes Mellitus refers to a group of common metabolic disorders that depicts hyperglycemia. As per WHO, the number of people with diabetes rose from 108 million in 1980 to 422 million in 2014. The global prevalence of diabetes among adults over 18 years of age rose from 4.7% in 1980 to 8.5% in 2014. Simple screening can help detect diabetes early and save lives. Many studies have found decreased phase angle among diabetics than controls but since age and BMI can be the confounders, there are few studies to match these parameters to draw the right conclusions. The objective of study was to do a matched comparison of the body composition (Body Fat%, Lean Body Mass and Total Body Water, Intracellular and Extracellular Water %) and biochemical investigations of Diabetics and Non-Diabetic Controls. Methods: The study population was taken from Indira G and hi Medical College, Shimla, which is one of the Tertiary care centers of Himachal Pradesh located in North India. All patients undergoing Body Composition measurements were diagnosed as diabetics on the basis of ADA (American Diabetic Association) diagnostic criteria. 60 diabetic patients fulfilling the inclusion criteria and 60 healthy age and sex-matched controls were enrolled in this study. Results: Matched analysis was done and it was found that the Phase angle among diabetics was lower (5.6° + 0.9°) than controls (6.3° + 1.1°) and was statistically significant, p-value <0.005. A comparison of biochemical investigations shows that there was a statistically significant difference between diabetics and controls with respect to FBS, HbA1C, Cholesterol, VLDL and HDL. Conclusion: Diabetics and controls were age, Sex and BMI matched with moderate physical activity. Waist Circumference (WC) was higher in diabetics indicating central obesity. The diabetics were found to be hypertensive with poor blood sugar control and dyslipidemia. The Phase Angle was decreased in diabetics than in controls, showing the prognosis of the disease.

Artificial Water Channels—Progress Innovations and Prospects

Artificial Water Channels—Progress Innovations and Prospects

Normative reference data for body composition in healthy indigenous populations on the Qinghai-Tibet Plateau.

Body composition represents an important aspect of physical fitness and has received increasing attention in recent years. The present study was designed and conducted to provide reference values for age-, sex-, and altitude-specific body composition for healthy indigenous Tibetan adults living on the Qinghai-Tibet Plateau, which has not yet been studied. A cross-sectional survey was conducted among 2,356 healthy Tibetan adults (1,433 females and 923 males) living on the Qinghai-Tibet Plateau for generations. The body composition of the participants was measured by bioelectrical impedance analysis (BIA). The measurements included weight, basal metabolic rate (BMR), fat-free mass (FFM), skeletal muscle mass (SMM), protein mass (PM), bone mass (BM), fat mass (FM), percentage of body fat (PBF), subcutaneous fat mass (SFM), visceral fat mass (VFM), total body water (TBW), intracellular water (ICW), and extracellular water (ECW). Overall, males had greater FFM, SMM, PM, BM, and water mass, whereas females were high in fat mass. Participants from plains generally had higher body composition values, and PM, BM, FM and body water values decreased with increasing altitude, with the lowest values found in >4,000 m Shigatse. FFM, SMM, PM, and BM tended to decrease with increasing age, whereas fat mass and ECW tended to increase with increasing age. This study provides the first normative reference data of body composition for healthy indigenous individuals on the Qinghai-Tibet Plateau. These datasets are important for future research related to body composition. A considerable decrease in body composition values in > 4,000 m-altitude areas suggested that body composition cutoff values should be established by altitude. Age-, sex-, and altitude-specific alterations in body composition values also inform the prevention and amendment of abnormal body composition changes and resultant health complications.

Bioelectrical impedance analysis during deresuscitation: correlation and agreement with cumulative fluid balance in ICU patients.

Bioelectrical impedance analysis (BIA) is a promising tool to evaluate the body composition of critically-ill patients. The present study aimed to assess its value as a fluid management monitoring tool during standardized deresuscitation strategy. A historical cohort of critically-ill adult patients with fluid overload and continuous renal replacement therapy was used to explore both relationship and agreement between changes in cumulative fluid balance and BIA-derived hydration variables within the 5days following initiation of deresuscitation strategy using net ultrafiltration. Correlations were described using Spearman's rank correlation coefficient, and agreement using Bland-Altman analysis for repeated measurements. Sixty-one couples of fluid shift measurements from 30 patients were analyzed. The deresuscitation strategy induced a negative mean (± SD) cumulative fluid balance (-4.2 ± 3.8 L) and a significant decrease in extra- and intracellular water (P < 0.001). Decreases in extra- and intracellular water were independent of weight variations inputted in the BIA device. Total body water (rho = 0.63), extracellular water (rho = 0.68), and intracellular water (rho = 0.67) were significantly correlated with cumulative fluid balance (all P values < 0.001). The limits of agreement did not allow interchangeability for a delta of 2L between cumulative fluid balance and BIA-derived hydration variables (P > 0.05). BIA hydration-derived variables are significantly correlated with cumulative fluid balance but the large limits of agreements exclude interchangeability of the measures.

Special features of microbial cake under high pressure conditions in microfiltration

Here, cell separation from microbial suspensions (gram-negative bacterium Escherichia coli, gram-positive bacterium Lactococcus lactis, and yeast Saccharomyces cerevisiae) was performed by dead-end microfiltration. From the results of three types of experiments, namely constant-rate and constant-pressure filtration, and constant-pressure consolidation, it was revealed that the microfiltration behaviors of microbial suspensions can be described on the basis of the pressure dependences of the average void ratio and specific resistance of the microbial cake. However, under high-pressure conditions, we found that the cake structure of Escherichia coli was changed, and the calculations were inconsistent with constant-rate filtration data. The data, such as constant-rate filtration behaviors, spectra of filtrate, electron micrographs of filter cake, and constant-pressure consolidation behaviors, indicated the possibility of cellular destruction of Escherichia coli under pressures above 700 kPa. In contrast, this phenomenon was not observed at pressures of up to 1000 kPa in yeast with different cell envelope compositions. Cellular destruction affected the filtration performance, and since intracellular water was discharged, the dehydration characteristics of the cake changed significantly. The findings on the properties of microbial cakes under high pressure obtained in this study are useful for improving the efficiency of filtration operations for microbial suspensions and dehydration operations for biological sludge.

Phenomenology of health

Health, as a phenomenon of a planetary scale, reflects the life of mankind, the world of animals and plants. Human health issues from the mid-20th century began to come out of the exclusive medical control. The increase in the average life expectancy of the population of developed countries, the globalization of economic, political, cultural life, the emergence of pandemics of viral infections - all these factors have shown that in maintaining the health of the population, the actual medical contribution is no more than 10%. The rest of the influence is exerted by economic, environmental, social and hereditary factors. The burden of disease of the population causes significant damage to the economies of even the most developed countries.&#x0D; Human health is a comprehensive, integrative assessment of the quality of his being for each specific time and age period. Thus, we consider health as a derivative of the ontogenetic scale. A feature of this scale is the unification on the time axis (x) of both calendar and biological ages. The axis (y) reflects the magnitudes of the influence of known determinants of health that accompany a person at each stage of his ontogenetic movement.&#x0D; One of the most important conditions for the functioning of the human body and animals is the constancy of the internal environment, defined as homeostasis. It is thanks to homeostasis that every cell of the body is in a relatively constant environment, which is an extracellular fluid. Earlier we drew attention to the fact that all the parameters of extracellular fluid can be divided into indicators of water-salt homeostasis (osmolality, concentrations of ions Na, K, Ca, pH). The task of water-salt homeostasis is to ensure water balance, both intracellular water content and the total amount in the body.&#x0D; The second group of homeostasis indicators is represented by metabolites (glucose, lipids, amino acids, proteins, urea, creatinine, bilirubin, etc.). On the one hand, metabolic indicators are quite stable, which made it possible to attribute them to homeostasis, but on the other hand, their most important feature is that they are very closely related to the functional state of the body (organs, tissues, cells), since the main task of metabolism is to adequately provide the organs and tissues of functioning systems with the necessary amount of energy and plastic substrates. Accordingly, with changing functions, the levels of the main metabolites should also change. At the same time, the main criterion for the adequacy of the metabolic support of functioning systems is not their homeostating concentration, but compliance with the changing needs of organs and tissues. That is, in the body it is necessary to ensure a sufficiently strong relationship between function and metabolism.&#x0D; In the literature, the subjective assessment of whether social factors affecting health can be avoided through structural changes in policy and practice appears to be the dominant way to determine the social determinant of health. In addition, the term "social" remains ambiguous and difficult to define within the clear boundaries of health care.&#x0D; There are already concerns about the requirements and approaches to their screening, as well as their benefits and unintended harm. A long list of CLE can prevent doctors from prioritizing screening for social determinants and referring patients to support services. Politicians may also be less inclined to continue working with such a long and growing list. In most government agencies, there are inherent barriers to adopting a social determinant approach in policymaking.&#x0D; A long list can add additional restrictions on adoption. A clear understanding of the "social determinants of health" is critical for all key stakeholders, including the public.

Water exchange detected by shutter speed dynamic contrast enhanced-MRI help distinguish solitary brain metastasis from glioblastoma

PurposeThis study aimed to explore the feasibility of transmembrane water exchange parameters detected by brain shutter speed (BSS) dynamic contrast enhanced (DCE)MRI, which is validated to be associated with aquaporin-4 expression, in distinguishing glioblastoma (GBM) from solitary brain metastasis (SBM). Methods40 patients (mean age: 58.6 ± 11.7 years old, male/female: 23/17) with GBM and 48 patients (mean age: 61.7 ± 10.5 years old, male/female: 28/20) with SBM were enrolled in this observational study. BSS DCE-MRI was performed before operation. Intravascular water efflux rate constant (kbo) and intracellular water efflux rate constant (kio) within the peritumoral region and enhancing tumor were calculated from SS-DCE, respectively. The difference of these two parameters between GBM and SBM was explored. Immunohistochemical staining aquaporin-4 of was performed to validate its underlying biological mechanism. ResultsThe kbo was found to be statistically different within both peritumoral region {SBM vs. GBM (s-1): 1.0[0.4,1.7] vs. 1.5[0.9,2.1], p = 0.009} and enhanced tumor {SBM vs. GBM (s-1): 0.2[0.1,0.5] vs. 0.4[0.1,1.3], p = 0.034}. Immunohistochemical analysis reveals the high perivascular aquaporin-4 expression in GBM may contribute the higher kbo value than that of SBM. Conclusionskbo derived from BSS DCE-MRI was an independent pathophysiological parameter for separating GBM from SBM, in which kbo might be associated with the perivascular aquaporin-4 expression.

Predictive Roles of Basal Metabolic Rate and Body Water Distribution in Sarcopenia and Sarcopenic Obesity: The link to Carbohydrates.

Sarcopenic obesity is a new category of obesity and is a specific condition of sarcopenia. This study aimed to find the relationship of the basal metabolic rate (BMR) and body water distribution with muscle health and their prospective roles in screening for sarcopenic obesity and sarcopenia. The role of nutrients such as carbohydrates in the relationship was further detected. A total of 402 elderly subjects were recruited. Body composition was estimated by bioelectrical impedance analysis. Sarcopenia was defined by the Asian Working Group for Sarcopenia 2019. The cutoff values were determined by the receiver operating characteristic curve. Mediation analyses were performed using SPSS PROCESS. Higher BMR and BMR/body surface area (BSA) were protective factors against sarcopenic obesity (OR = 0.047, p = 0.004; OR = 0.035, p = 0.002) and sarcopenia (OR = 0.085, p = 0.001; OR = 0.100, p = 0.003) in elderly people. Low extracellular water (ECW)/intracellular water (ICW) and ECW/total body water (TBW) were negatively correlated with the skeletal muscle index (SMI). The intake of dietary carbohydrates in people with sarcopenic obesity was the lowest, but in subjects with obesity, it was the highest (p = 0.023). The results of the moderated mediation model showed that BMR fully mediated the positive relationship between carbohydrates and SMI, which was more obvious in the population with an abnormal body water distribution. BMR or BMR/BSA had the potential role of predicting a higher risk of sarcopenic obesity and sarcopenia. Higher BMR and lower ECW/ICW and ECW/TBW may benefit muscle health. The overconsumption of carbohydrates (especially > AMDR) might be a risk factor for obesity. Moderate dietary carbohydrate intake might promote SMI by regulating BMR and body water distribution in the elderly.

Variations of distance and accelerometry-based GPS measures and their influence on body composition in professional women soccer players

External intensity quantification and body composition assessments across the season allow soccer coaches to adjust the intensity during training sessions, thereby avoiding excessive fatigue and helping players maximize their physical fitness status during matches. Thus, the aims of this study were (1) to describe variations in external intensity periods of distance and accelerometry-based measures across the early and mid-competitive phases and (2) to analyze whether the intensity variations influenced body composition across the 2019/20 competitive season. Ten players from a Portuguese BPI Ligue team (professional league) participated in this study. The participants completed ≥80% of 57 training sessions and 13 matches. The athletes were assessed in three phases (before the start of the season, after 2 months, and after 4 months) for the following variables: body fat mass, soft lean mass, fat-free mass, intracellular water, extracellular water, total body water, and phase angle (50 kHz) through bioelectrical impedance analysis (InBody S10). A 10-Hz GPS device (PlayerTek) was used to collect distance and accelerometry-based measures, which included total distance, high-speed running distance, sprint distance, acceleration, deceleration, and player load. Repeated-measures analysis of covariance (ANCOVA) with GPS-derived measures as covariates or repeated-measures analysis of variance (ANOVA) was used to compare the three moments of assessment. Although the patterns of variables’ responses were not the same as the season progressed, the values of body fat mass, fat-free mass, intracellular water, extracellular water, total body water, ratios of ECW/TBW, ECW/ICW, and phase angle improved. Variations in external intensity measures seem to influence the body composition variables across the season. These results may indicate good adaptations to the training and conditioning strategies managed by the coach and technical staff.

Body Fluid Estimation Via Segmental Multi-Frequency Bioelectrical Impedance Analysis Following Acute Resistance Exercise

Segmental multi-frequency bioelectrical impedance analysis (S-MFBIA) estimates body composition and fluids by passing electrical currents through the body and can separate the body into distinct segments. The minimum required abstention from exercise before S-MFBIA is unclear. PURPOSE: The purpose of this study was to monitor changes in total body water (TBW), intracellular water (ICW), and extracellular water (ECW) estimated via S-MFBIA following acute, localized bouts of resistance exercise (RE). METHODS: Thirty-two female (n = 18; age: 22.7 ± 1.4 y; height: 167.5 ± 7.5 cm; body mass: 66.6 ± 14.5 kg; body fat: 30.3 ± 6.2%) and male (n = 14; age: 24.2 ± 2.9; height: 178.7 ± 5.3; body mass: 85.7 ± 7.8 kg; body fat: 19.6 ± 6.9%) resistance-trained volunteers completed three randomly assigned conditions in a crossover design. Each RE protocol (REUPPER or RELOWER) consisted of three exercises and began with two warm-up sets of 12-15 repetitions per exercise. This was followed by a RE circuit of 5 sets of 10 repetitions per exercise with a one-minute rest interval between circuits. In the resting (REST) condition, participants did not complete any physical activity. S-MFBIA was performed at five timepoints: pre-exercise, immediate post-exercise, 15-, 30-, and 60-minutes post-exercise. Data were analyzed using linear mixed-effects models with a random intercept for participant. In all models, REST was the reference condition, and pre-exercise was the reference time point. RESULTS: Although body mass did not differ between conditions, condition by time interactions were observed for TBW, ICW, and ECW (p < 0.001 each), with the higher values observed at post-exercise time points in REUPPER as compared to the REST condition. Mean differences between REUPPER and REST for TBW, ICW, and ECW ranged from 0.6-1.0 kg, 0.4-0.6 kg, and 0.2-0.4 kg, respectively. Conversely, RELOWER did not alter fluid estimates. CONCLUSIONS: An acute increase in TBW, ICW, and ECW is detected by S-MFBIA after a single bout of upper body, but not lower body, RE. This could be due to the smaller initial diameter and greater relative change in diameter of the arms as compared to legs. Due to the potential of artificial body fluid changes, users should avoid exercise - particularly upper body exercise - prior to S-MFBIA assessments.

CrossFit Participants And Collegiate Athletes Exhibit Consistent Differences In Hydration Parameters

Collegiate athletics programs and CrossFit facilities are environments that are associated with intense, competitive, and highly structured resistance training. Although the characteristics of stress are unique to each setting, maintenance of hydration is important to the health and performance of both exercising populations. PURPOSE: To examine differences in hydration parameters between Division I collegiate athletes and consistent CrossFit participants. METHODS: We scanned 288 women (28.5% athletes) and 244 men (13.1% athletes) using the InBody 770 bioelectrical impedance analyzer (InBody USA, Cerritos, CA). There were 7 women's sports and 6 men's sports represented. We used coarsened exact matching to generate subsamples that were matched for sex, age, and bodyweight; 96 subjects were retained (48 Division I athletes, 48 CrossFit members). This was considered the study sample. Multiple linear regression models, holding height and body fat percent constant, tested for differences in total body water (TBW), intracellular water (ICW), and extracellular water (ECW). Significance was set at p < 0.05. RESULTS: Across the study sample, subject age was 21.7 ± 3.1 yr, height was 68.2 ± 4.0 in, weight was 169.8 ± 28.0 lb, body fat percent was 20.4 ± 10.0%, TBW was 98.4 ± 18.7 lb, ICW was 62.2 ± 12.0 lb, and ECW was 36.2 ± 6.7 lb. Holding constant height and body fat percent, linear regression revealed CrossFit participants to have an additional 8.2 lb of TBW (p < 0.001; 95% CI: 3.8 to 12.6); the overall model was significant (p < 0.001; r2 = 0.754). Assessment of individual fluid compartments revealed CrossFit participants to have 5.3 lb more ICW (p = 0.001; 95% CI: 2.3 to 8.2) and 2.9 lb more ECW (p < 0.001; 95% CI: 1.4 to 4.4). Both models were significant (p < 0.001; ICW r2 = 0.735; ECW r2 = 0.781). CONCLUSIONS: After matching samples for sex, age, and bodyweight, and holding height and body fat percent constant, CrossFit participants emerged with significantly higher values in TBW, ICW, and ECW. Although universities generally employ supervisory staff to monitor athlete training, our results indicate that competitive athletes may be less hydrated than other exercising populations. More focus on hydration practices may be warranted at the collegiate level.

Effect Of Acute Feeding On Raw Bioimpedance Values And Body Water Estimates In Healthy Adults

Raw bioimpedance values of resistance (R), reactance (Xc), impedance (Z), and phase angle (PhA) are indicators of cell hydration, health, and membrane integrity. There is increasing interest in using these values as indicators of hydration and nutritional status, but effects of acute nutritional intake on raw bioimpedance values is currently unknown. PURPOSE: To determine the effects of acute feeding on raw bioimpedance values and derived body water estimates (total body water [TBW], extracellular water [ECW], intracellular water [ICW]) obtained from multi-frequency bioelectrical impedance spectroscopy (BIS). METHODS: Twenty-nine healthy young adults (59% Female; Age: 21.3 ± 2.7 yrs; Height: 172.5 ± 9.2 cm; Weight: 71.2 ± 10.3 kg) completed three randomly assigned feeding conditions: high carbohydrate (CHO: 116.5 g CHO; 882.5 g total; 0.83 ml fluid), high protein (PRO; 63.5 g PRO; 913 g total; 0.83 ml fluid), and fasted (FAST; 8 hrs fasted). Whole-body, multi-frequency BIS was completed one hour post-meal consumption. Differences in raw bioimpedance values and derived body water estimates between feeding conditions were evaluated using separate repeated measure ANOVAs covaried for average urine specific gravity to account for pre-visit hydration status. RESULTS: There were no significant differences in raw bioimpedance values [R (FAST, CHO, PRO means: 543.0, 545.1, 548.6 Ω; p = 0.418), Xc (67.2, 67.7, 67.7 Ω; p = 0.453), Z (547.2, 549.4, 552.8 Ω; p = 0.416), PhA (7.14, 7.16, 7.12°; p = 0.680)] or derived body water estimates [TBW (40.0, 40.0, 39.8 L; p = 0.289), ECW (16.1, 16.1, 16.1 L; p = 0.131), or ICW (23.9, 23.9, 23.8 L; p = 0.671)] between feeding conditions. CONCLUSION: Acute feeding did not alter raw bioimpedance values taken 1 hr post-meal in healthy young adults. Bioimpedance may not be sensitive to acute changes in nutrition/hydration or consumption of food/drink 1 hr prior to testing was not a long enough equilibration time. Acute food intake may not need to be restricted prior to bioimpedance measurements, which increases feasibility of application in clinical and athletic populations.

A novel pre-magnetized ZVI/PS pretreatment for improving sludge dewaterability: The role of EPS fractions.

The dewaterability of waste-activated sludge (WAS) has been extensively examined using zero-valent iron (ZVI)-based advanced oxidation processes (AOPs). However, the high dosage and low utilization efficiencies of ZVI cast doubt on the dependability and viability of ZVI-based AOPs. In this study, we successfully demonstrated pre-magnetization as an efficient, chemical-free, and ecological method for improving the efficiency of sludge dewatering by ZVI/persulfate (PS) process, in which the reduction ratios of capillary suction time (CST) and specific resistance to filtration (SRF) increased by 8.67% and 11.06% under optimal conditions, respectively. The highly active Fe2+ released during ZVI corrosion may be more essential than ZVI itself during PS activation, which could be strengthened by pre-magnetization. Both homogeneous and heterogeneous Fe2+ could react with PS to produce aqueous hydroxyl radicals (∙OH) and sulfate radicals (SO4-∙) as well as surface-bound ∙OH and SO4-∙, further decomposing bound-extracellular polymeric substances fractions, broking hydrophilic functional groups and compounds, altering protein secondary structure to expose more hydrophobic sites, and releasing abundant EPS-bound water. Due to the protection of tightly-bound extracellular polymeric substances (TB-EPS) and the competitive oxidation of organics released during the early disintegration stage, radical oxidation primarily occurs at extracellular levels, releasing a bit of intracellular water. Besides, polysaccharides in TB-EPS may function a more significant role in flocculation than proteins, and a porous structure favorable to drainage will be formed after the pre-magnetized ZVI/PS treatment. The cost-benefit analysis further reveals that the Pre-ZVI/PS process presents high reusability and utilization, making it potential for particle application in sludge dewatering.

Role of Transmembrane Water Exchange in Glioma Invasion/Migration: In Vivo Preclinical Study by Relaxometry at Very Low Magnetic Field.

Simple SummarySince the pioneering work of Damadian (1971), the longitudinal T1-relaxation of nuclear magnetic resonance (NMR) has been reported to generate significant contrast between cancer and healthy tissues at low magnetic fields. However, low NMR sensitivity was a substantial obstacle. Fast field cycling NMR (FFC-NMR) can overcome this problem and is commercially available for physics/chemistry research since around the years 2000s. Herein, using FFC-NMR in vivo, we show that T1-relaxation measured at very low fields is sensitive to transmembrane water exchange, thus allowing the discrimination between glioma invasion/migration and proliferation. Aquaporins 4 and 1 are found to be upregulated in invasion/migration, indicating that water exchange modulates T1-relaxations in glioma, via these aquaporins action. Overall, results suggest that, by blocking the aquaporin functions, the T1-relaxation should decrease in invasion/migration glioma. Results also stipulate that the entire invasion/migration volume could be visualized by FFC imaging, noninvasively. This may impact the medical community since invasion/migration delineation remains challenging by any medical imaging modality.This work shows that the longitudinal relaxation differences observed at very low magnetic fields between invasion/migration and proliferation processes on glioma mouse models in vivo are related to differences in the transmembrane water exchange basically linked to the aquaporin expression changes. Three glioma mouse models were used: Glio6 and Glio96 as invasion/migration models and U87 as cell proliferation model. In vivo proton longitudinal relaxation-rate constants (R1) at very low fields were measured by fast field cycling NMR (FFC-NMR). The tumor contribution to the observed proton relaxation rate, R1tum (U87: 12.26 ± 0.64 s−1; Glio6: 3.76 ± 0.88 s−1; Glio96: 6.90 ± 0.64 s−1 at 0.01 MHz), and the intracellular water lifetime, τin (U87: 826 ± 19 ms; Glio6: 516 ± 8 ms; Glio96: 596 ± 15 ms), were found to be good diagnostic hallmarks to distinguish invasion/migration from proliferation (p < 0.01 and 0.001). Overexpression of AQP4 and AQP1 were assessed in invasion/migration models, highlighting the pathophysiological role of these two aquaporins in water exchange that, in turn, determine the lower values in the observed R1 relaxation rate constant in glioma invasion/migration. Overall, our findings demonstrate that τin and R1 (measured at very low fields) are relevant biomarkers, discriminating invasion/migration from proliferation in vivo. These results highlight the use of FFC-NMR and FFC-imaging to assess the efficiency of drugs that could modulate aquaporin functions.

The state of water molecules induces changes in the topologies and interactions of G-quadruplex DNA aptamers in hydrated ionic liquid

Herein, the effects of the bound state of water molecules were investigated on the topologies and interactions of G-quadruplex DNA aptamers by using hydrated ionic liquids (ILs). Since intracellular water molecules are generally expected to exist in the bound state and not as free molecules that exist in the typical in vitro media, we proposed hydrated ILs as potential candidates for controlling the state of water molecules. Hydrated ILs have been reported to dissolve proteins without compromising their higher-order structures. In this study, the structures and interactions of three G-quadruplex DNA aptamers (one thrombin-binding aptamer and two vascular endothelial growth factor 165-binding aptamers), with their target molecules were analyzed with circular dichroism (CD) spectroscopy and enzyme-linked oligonucleotide assay by changing the water content of hydrated cholinium dihydrogen phosphate (Hy[ch][dhp]). Hy[ch][dhp] allowed the effective dissolution of G-quadruplex DNA aptamers while maintaining their structure and binding affinity to the target molecule. The water content of Hy[ch][dhp] induced changes in the CD spectra, suggesting changes in the topology of G-quadruplex structure. Increased structural stability and binding properties indicated molecular recognition and smooth dehydration progress in Hy[ch][dhp] via regulation of the state of water molecules.