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World Journal of Gastroenterology Sep 2014Recent studies show that ion channels/transporters play important roles in fundamental cellular functions that would be involved in the cancer process. We review the... (Review)
Review
Recent studies show that ion channels/transporters play important roles in fundamental cellular functions that would be involved in the cancer process. We review the evidence for their expression and functioning in human gastric cancer (GC), and evaluate the potential of cellular physiological approach in clinical management. Various types of ion channels, such as voltage-gated K(+) channels, intracellular Cl(-) channels and transient receptor potential channels have been found to express in GC cells and tissues, and to control cell cycles. With regard to water channels, aquaporin 3 and 5 play an important role in the progression of GC. Regulators of intracellular pH, such as anion exchanger, sodium-hydrogen exchanger, vacuolar H(+)-ATPases and carbonic anhydrases are also involved in tumorigenesis of GC. Their pharmacological manipulation and gene silencing affect cellular behaviours, suggesting their potential as therapeutic targets for GC. Our studies indicate the intracellular Cl(-) concentration could act as a mediator of cellular signaling and control cell cycle progression in GC cells. Further, we demonstrate the cytocidal effects of hypotonic shock on GC cells, and indicate that the blockade of Cl(-) channels/transporters enhances these effects by inhibiting regulatory volume decrease. A deeper understanding of molecular mechanisms may lead to the discovery of these cellular physiological approaches as a novel therapeutic strategy for GC.
Topics: Animals; Antineoplastic Agents; Drug Design; Humans; Hydrogen-Ion Concentration; Ion Channels; Molecular Targeted Therapy; Osmolar Concentration; Signal Transduction; Stomach Neoplasms; Treatment Outcome
PubMed: 25206263
DOI: 10.3748/wjg.v20.i33.11560 -
PloS One 2020Human breast milk (BM) fortification is required to feed preterm newborns with less than 32 weeks of gestation. However, addition of fortifiers increases osmolarity and...
BACKGROUND
Human breast milk (BM) fortification is required to feed preterm newborns with less than 32 weeks of gestation. However, addition of fortifiers increases osmolarity and osmolarity values higher than 450 mOsm/kg may be related to gastrointestinal pathology. Hence, fortifier selection and dosage are key to achieve optimal feeding.
OBJECTIVES
To compare the effect on osmolality of adding different fortifications, including recently developed formulations, to BM and to study evolution of osmolarity over time in supplemented BM.
METHODS
Frozen mature BM from 10 healthy mothers of premature newborns was fortified with each of the following human milk fortifiers (HMF): AlmirónFortifier®, NANFM85®, or PreNANFM85®. In addition, fortified BMs were modified with one of the following nutritional supplements (NS): Duocal MCT®, Nutricia® AminoAcids Mix, or Maxijul®. Osmolality of BM alone, fortified and/or supplemented was measured at 1 and 22 hours after their preparation. All samples were kept at 4°C throughout the study.
RESULTS
Osmolality of BM alone was close to 300 mOsm/kg and did not change over 22 hours. When equicaloric amounts of HMF AlmirónFortifier®, NANFM85®, and PreNANFM85® were added to BM, osmolality increased roughly to 480 mOsm/kg with the first two fortifiers and only to 433±6 mOsm/kg with the third one. Upon addition of any of four different NSs to BM modified with AlmirónFortifier® and NANFM85®, osmolality reached values greater than 520 mOsm/kg, while osmolality of PreNANFM85® with two out of the four NSs remained below 490 mOsm/kg. NSs supplementing carbohydrates and hydrolysed proteins resulted into a higher increase of BM osmolarity. Osmolality increased significantly with time and, after 22h, only BM modified with PreNANFM85® remained below 450 mOsm/kg.
CONCLUSIONS
Upon addition of the HMFs tested, BM osmolality increases significantly and keeps raising over time. All HMFs but the recently developed PreNAN FM85® at 4% exceed the AAP recommended threshold for osmolarity of 450 mOsm/kg. Addition of NSs to PreNAN FM85® at 4% significantly increases osmolality above 450 mOsm/Kg. Thus, using PreNAN FM85® at 5% may be preferable to adding nutritional supplements since nutritional recommendations by the ESPGHAN are reached with a lower increase in osmolality.
Topics: Adult; Female; Food, Fortified; Humans; Infant Nutritional Physiological Phenomena; Infant, Newborn; Infant, Premature; Milk, Human; Nutrients; Osmolar Concentration
PubMed: 32479524
DOI: 10.1371/journal.pone.0233924 -
International Journal of Molecular... Jul 2019Epithelia act as a barrier to the external environment. The extracellular environment constantly changes, and the epithelia are required to regulate their function in... (Review)
Review
Epithelia act as a barrier to the external environment. The extracellular environment constantly changes, and the epithelia are required to regulate their function in accordance with the changes in the environment. It has been reported that a difference of the environment between the apical and basal sides of epithelia such as osmolality and hydrostatic pressure affects various epithelial functions including transepithelial transport, cytoskeleton, and cell proliferation. In this paper, we review the regulation of epithelial functions by the gradients of osmolality and hydrostatic pressure. We also examine the significance of this regulation in pathological conditions especially focusing on the role of the hydrostatic pressure gradient in the pathogenesis of carcinomas. Furthermore, we discuss the mechanism by which epithelia sense the osmotic and hydrostatic pressure gradients and the possible role of the tight junction as a sensor of the extracellular environment to regulate epithelial functions.
Topics: Animals; Biological Transport; Cytoskeleton; Epithelial Cells; Humans; Hydrostatic Pressure; Neoplasms; Osmolar Concentration; Tight Junctions
PubMed: 31319610
DOI: 10.3390/ijms20143513 -
Soft Matter Apr 2021Supramolecular self-assembly enables living organisms to form highly functional hierarchical structures with individual components self-organized across multiple length...
Supramolecular self-assembly enables living organisms to form highly functional hierarchical structures with individual components self-organized across multiple length scales. This has inspired work on multicomponent supramolecular materials to understand factors behind co-assembly versus self-sorting of molecules. We report here on a supramolecular system comprised of negatively charged peptide amphiphile (PA) molecules, in which only a tiny fraction of the molecules (0.7 mol%) were covalently conjugated to one of two different fluorophores, half to fluorescein isothiocyanate (FTIC) and the other half to tetramethylrhodamine (TAMRA). Confocal microscopy of the system revealed self-sorting of the two different fluorescent PA molecules, where TAMRA PA is concentrated in micron-scale domains while FITC PA remains dispersed throughout the sample. From Förster resonance energy transfer and fluorescence recovery experiments, we conclude that conjugation of the negatively charged FITC to PA significantly disrupts its co-assembly with the 99.3 mol% of unlabeled molecules, which are responsible for formation of micron-scale domains. Conversely, conjugation of the zwitterionic TAMRA causes no such disruption. Interestingly, this dissimilar behavior between FITC and TAMRA PA causes them to self-sort at large length scales in the supramolecular system, mediated not by specific interactions among the individual fluorophores but instead by their different propensities to co-assemble with the majority component. We also found that greater ionic strength in the aqueous environment of the system promotes mixing by lowering the electrostatic barriers involved in self-sorting. Our results demonstrate great thermodynamic subtlety in the driving forces that mediate self-sorting versus co-assembly in supramolecular peptide assemblies.
Topics: Osmolar Concentration; Peptides; Static Electricity; Thermodynamics; Water
PubMed: 33705512
DOI: 10.1039/d1sm00113b -
Advances in Physiology Education Dec 2016
Review
Topics: Congresses as Topic; Humans; Isotonic Solutions; Osmolar Concentration; Osmosis; Physiology; Sodium Chloride
PubMed: 27756727
DOI: 10.1152/advan.00080.2016 -
Yonsei Medical Journal Jul 2021Plasma osmolality, a marker of dehydration, is associated with cardiovascular mortality. We aimed to investigate whether elevated plasma osmolality is associated with...
PURPOSE
Plasma osmolality, a marker of dehydration, is associated with cardiovascular mortality. We aimed to investigate whether elevated plasma osmolality is associated with case fatality within 1 year after severe acute ischemic stroke.
MATERIALS AND METHODS
We included severe ischemic stroke patients (defined as National Institutes of Health Stroke Scale ≥15 score) within 24 hours from symptom onset admitted to the Department of Neurology, West China Hospital between January 2017 and June 2019. Admission plasma osmolality was calculated using the equation 1.86*(sodium+potassium)+1.15*glucose+urea+14. Elevated plasma osmolality was defined as plasma osmolality >296 mOsm/kg, indicating a state of dehydration. Study outcomes included 3-month and 1-year case fatalities. Multivariable logistic regression was performed to determine independent associations between plasma osmolality and case fatalities at different time points.
RESULTS
A total of 265 patients with severe acute ischemic stroke were included. The mean age was 71.2±13.1 years, with 51.3% being males. Among the included patients, case fatalities were recorded for 31.7% (84/265) at 3 months and 39.6% (105/265) at 1 year. Elevated plasma osmolality (dehydration) was associated with 3-month case fatality [odds ratio (OR) 1.98, 95% confidence interval (CI) 1.07-3.66, =0.029], but not 1-year case fatality (OR 1.51, 95% CI 0.84-2.72, =0.165), after full adjustment for confounding factors.
CONCLUSION
Elevated plasma osmolality was independently associated with 3-month case fatality, but not 1-year case fatality, for severe acute ischemic stroke.
Topics: Aged; Aged, 80 and over; Brain Ischemia; China; Female; Humans; Ischemic Stroke; Male; Middle Aged; Osmolar Concentration; Risk Factors; Stroke
PubMed: 34164957
DOI: 10.3349/ymj.2021.62.7.600 -
Public Health Nutrition Sep 2022Evaluating the association of water intake and hydration status with nephrolithiasis risk at the population level.
OBJECTIVE
Evaluating the association of water intake and hydration status with nephrolithiasis risk at the population level.
DESIGN
It is a cross-sectional study in which daily total plain water intake and total fluid intake were estimated together with blood osmolality, urine creatinine, urine osmolality, urine flow rate (UFR), free water clearance (FWC) and urine/blood osmolality ratio (U:B). The associations of fluid intake and hydration markers with nephrolithiasis were evaluated using multivariable logistic regression.
SETTING
General US population.
PARTICIPANTS
A total of 8195 adults aged 20 years or older from the National Health and Nutritional Examination Survey 2009-2012 cycles.
RESULTS
The population medians (interquartile ranges, IQR) for daily total plain water intake and total fluid intake were 807 (336-1481) and 2761 (2107-3577) ml/d, respectively. The adjusted OR (95 % CI) of nephrolithiasis for each IQR increase in total plain water intake and total fluid intake were 0·92 (95 % CI 0·79, 1·06) and 0·84 (95 % CI 0·72, 0·97), respectively. The corresponding OR of nephrolithiasis for UFR, blood osmolality, U:B and urine creatinine were 0·87 (95 % CI 0·76, 0·99), 1·18 (95 % CI 1·06, 1·32), 1·38 (95 % CI 1·17, 1·63) and 1·27 (95 % CI 1·11, 1·45), respectively. A linear protective relationship of fluid intake, UFR and FWC with nephrolithiasis risk was observed. Similarly, positive dose-response associations of nephrolithiasis risk with markers of insufficient hydration were identified. Encouraging a daily water intake of >2500 ml/d and maintaining a urine output of 2 l/d was associated with a lower prevalence of nephrolithiasis.
CONCLUSION
This study verified the beneficial role of general water intake recommendations in nephrolithiasis prevention in the general US population.
Topics: Adult; Biomarkers; Creatinine; Cross-Sectional Studies; Drinking; Humans; Kidney Calculi; Nutrition Surveys; Osmolar Concentration
PubMed: 35514256
DOI: 10.1017/S1368980022001033 -
Journal of Clinical Laboratory Analysis Jan 2021Automated flow cytometry-based urine analyzer is increasingly being used to identify and enumerate cells and particles in urine specimens. It measures electrical...
BACKGROUND
Automated flow cytometry-based urine analyzer is increasingly being used to identify and enumerate cells and particles in urine specimens. It measures electrical conductivity which could be transformed to osmolality. Using this machine, all urine specimens could be screened for osmolality without requiring a separate dedicated device. We evaluated the performance of the new instrument, the UF-5000 (Sysmex Corporation), in the measurement of urine osmolality.
METHODS
The precision of urine osmolality measurement by the UF-5000 was evaluated for 20 days and 4 times a day for 2 concentrations. The linearity and detection capability were evaluated according to the Clinical and Laboratory Standards Institute guidelines. For comparison, 270 random urine specimens from patients were tested simultaneously using the UF5000 and the OsmoPro micro-osmometer (Advanced instruments).
RESULTS
The laboratory-based coefficient variations were less than 5%. Urine osmolality using the UF-5000 has a verified linear range (y = 1.097x + 16.91, R = .997). Within the comparison analysis, the mean difference was not large (-7.72%) but each differences were largely dispersed with 95% limits of agreement (LoA) from -70.5 to 55.06%, and the mean absolute difference -28.3 mOsm/kg with 95% LoA from -295.13 to 238.45 mOsm/kg. Cohen's kappa value was 0.54 (95% CI, 0.45-0.63).
CONCLUSIONS
The UF-5000 measured conductivity and generated an acceptable quantitative analysis of urine osmolality. When compared with the results of the freezing point depression method used by the OsmoPro, a percentage of the measured urine osmolality by the UF-5000 was outside the allowable limit.
Topics: Automation, Laboratory; Electric Conductivity; Flow Cytometry; Humans; Osmolar Concentration; Urinalysis; Urine
PubMed: 32969530
DOI: 10.1002/jcla.23586 -
BMC Nephrology Sep 2021Decreased kidney function is commonly caused by hypovolemia. When hypovolemic, the kidney reabsorbs water resulting in concentrated urine. Osmolality is a measure of...
BACKGROUND
Decreased kidney function is commonly caused by hypovolemia. When hypovolemic, the kidney reabsorbs water resulting in concentrated urine. Osmolality is a measure of urine concentration which is more objective than self-reported fluid intake. It has a positive association with hypovolemia. However, it remains controversial whether osmolality is associated with decreased kidney function and/or albuminuria.
METHODS
We conducted a cross-sectional analysis of the 2009-2012 National Health and Nutrition Examination Survey, a standardized survey in the U.S.
POPULATION
Participants aged 18-70 years old with random urine osmolality were included. Osmolality was categorized as quartiles. Decreased kidney function was defined by estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73m and albuminuria was defined by albumin-to-creatinine ratio ≥ 30 mg/gm. We performed multivariable regression via four sequential models.
RESULTS
Our study sample included 7,373 participants. The mean age was 42.9 ± 0.4 years. Overall, 51.4% were male and 67.3% were white. The mean osmolality was 603.8 mOsm/kg and 629.1 mOsm/kg in those with and without decreased eGFR and/or albuminuria, respectively. The number of cases was 610 (6.7%). The prevalence from the lowest to highest quartiles of osmolality was 116 (6.2%), 213 (8.6%), 179 (7.5%), and 102 (4.3%), respectively (p-value for trend = 0.02). The relationship between osmolality and eGFR appeared nonlinear. After adjustment for demographic, social, cardiovascular, and dietary risk factors, there was no significant association of osmolality quartiles with decreased eGFR and/or albuminuria (odds ratio [OR] 0.77, 95% confidence interval [CI] 0.56, 1.07). In sensitivity analyses, osmolality ≥ 500 mOsm/kg was associated with lower eGFR (adjusted ß -1.13, 95% CI -1.98, -0.28). In pre-specified subgroup analyses, osmolality had a statistically significant negative correlation with eGFR among individuals with eGFR ≥ 60 mL/min/1.73m, but a positive correlation among those with eGFR < 60 mL/min/1.73m (adjusted ß -0.19, 95% CI -0.36, -0.01 versus adjusted ß 0.50, 95% CI 0.05, 0.96; p-value for interaction = 0.016).
CONCLUSIONS
Higher osmolality was significantly associated with lower eGFR among adults with eGFR ≥ 60 mL/min/1.73m Future research should examine the relationship between osmolality and change in kidney function over time among adults with normal eGFR.
Topics: Adult; Aged; Albuminuria; Cross-Sectional Studies; Female; Glomerular Filtration Rate; Humans; Kidney; Male; Middle Aged; Nutrition Surveys; Osmolar Concentration; Prevalence; Renal Insufficiency, Chronic; United States; Urine
PubMed: 34507548
DOI: 10.1186/s12882-021-02478-9 -
Clinical Nutrition ESPEN Jun 2024Patients with an ileostomy often have impaired quality of life, sodium depletion, secondary hyperaldosteronism, and other organ-specific pathologies. The osmolality of... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Patients with an ileostomy often have impaired quality of life, sodium depletion, secondary hyperaldosteronism, and other organ-specific pathologies. The osmolality of oral supplements influences ileostomy output and increases sodium loss. We hypothesized the existence of an osmolality range in which fluid absorption and secondary natriuresis are optimal.
METHODS
This was a single-center, quasi-randomized crossover intervention study, including patients with an ileostomy and no home parenteral support. After an 8-h fasting period, each patient ingested 500 mL of 3-18 different oral supplements and a standardized meal during the various intervention periods, followed by a 6-h collection of ileostomy and urine outputs. The primary outcome was 6-h ileostomy output.
RESULTS
A total of 14 ileostomy patients with a median age of 65 years (interquartile range 38-70 years) were included. The association between osmolalities (range 5-1352 mOsm/kg) and ileostomy output forecasted an S-curve. A linear association between osmolality of oral supplements (range 290-600 mOsm/kg) and ileostomy output was identified and assessed with a mixed-effects model. Ileostomy output increased by 57 g/6 h (95% confidence interval (CI) 21-94) when the oral supplement osmolality increased by 100 mOsm/kg (p = 0.005).
CONCLUSION
Osmolality in oral supplements correlated with ileostomy output. Our results indicate that patients with an ileostomy may benefit from increased ingestion of oral supplements with osmolalities between 100 and 290 mOsm/kg. We define this range as the Goldilocks zone, equivalent to optimal fluid and electrolyte absorption.
Topics: Humans; Ileostomy; Middle Aged; Aged; Male; Female; Dietary Supplements; Adult; Osmolar Concentration; Cross-Over Studies; Administration, Oral; Sodium
PubMed: 38777478
DOI: 10.1016/j.clnesp.2024.03.003