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Clinical Toxicology (Philadelphia, Pa.) Nov 2023Many hospitals are unable to determine toxic alcohol concentrations in a clinically meaningful time frame. Thus, clinicians use surrogate markers when evaluating...
INTRODUCTION
Many hospitals are unable to determine toxic alcohol concentrations in a clinically meaningful time frame. Thus, clinicians use surrogate markers when evaluating potentially poisoned patients.
INDEX CASE
A patient presented after an intentional antifreeze (ethylene glycol) ingestion with an osmol gap of -10.6 that remained stable one hour later. Further investigation revealed that the serum osmolality was calculated and not measured. The true osmol gap was 16.4, which correlated to a measured ethylene glycol concentration of 808 mg/L (80.8 mg/dL, 13.0 mmol/L).
SURVEY
A telephone survey of hospital laboratories in our catchment area was performed to investigate the potential for similar events.
RESULTS
Thirty-eight (47 percent) hospitals responded. No laboratories were able to test for toxic alcohols. One hospital (2.6 percent) reported routinely calculating osmolality based on chemistries, while two hospitals (5.3 percent) reported scenarios in which this might occur. Thirty-five (92.1 percent) hospitals could directly measure osmolality. Two hospitals (5.3 percent) were reliant on outside laboratories for osmolality measurement.
LIMITATIONS
The 47 percent response rate and one geographic area are significant limitations.
DISCUSSION
Over 10 percent of hospitals that responded could have significant difficulty assessing patients with toxic alcohol ingestion.
CONCLUSIONS
Until the standard of rapidly obtaining toxic alcohol concentrations is broadly implemented, we recommend that policies and procedures be put in place to minimize errors associated with the determination of the osmol gap.
Topics: Humans; Laboratories; Ethanol; Ethylene Glycol; Osmolar Concentration
PubMed: 38060329
DOI: 10.1080/15563650.2023.2286914 -
Chemosphere Sep 2023The environmental issues caused by nanoplastics (NPs) are increasingly noticeable. Environmental behavior study of the NPs could provide vital information for their...
The environmental issues caused by nanoplastics (NPs) are increasingly noticeable. Environmental behavior study of the NPs could provide vital information for their environmental impact assessment. However, associations between NPs' inherent properties and their sedimentation behaviors were seldom investigated. In this study, six types of PSNPs (polystyrene nanoplastics) with different charges (positive and negative) and particle sizes (20-50 nm, 150-190 nm and 220-250 nm) were synthesized, and their sedimentations under different environmental factors, (e.g., pH value, ionic strength (IS), electrolyte type and natural organic matter) were investigated. Results displayed that both particle size and surface charge would affect the sedimentation of PSNPs. The maximum sedimentation ratio of 26.48% was obtained in positive charged PSNPs with size of 20-50 nm, while the minimum sedimentation ratio of 1.02% was obtained in negative charged PSNPs with size of 220-250 nm at pH 7.6. The pH value shift (range of 5-10) triggered negligible changes of sedimentation ratio, the average particle size and the Zeta potential. Small size PSNPs (20-50 nm) showed higher sensitivity to IS, electrolyte type and HA condition than large size PSNPs. At high IS value ( [Formula: see text] = 30 mM or IS = 100 mM), the sedimentation ratios of the PSNPs all increased differently according to their properties, and the sedimentation promoting effect of CaCl was more significant on negative charged PSNPs than positive charged PSNPs. When [Formula: see text] increased from 0.9 to 9 mM, the sedimentation ratios of negative charged PSNPs increased by 0.53%-23.49%, while that of positive charged PSNPs increased by less than 10%. Besides, humic acid (HA) addition (1-10 mg/L) would lead to a stable suspension status for PSNPs in water with different degree and perhaps different mechanism due to their charge characteristics. These results showed new light on influence factor studies of NPs' sedimentation and would be helpful for further knowledge of NPs' environmental behaviors.
Topics: Microplastics; Polystyrenes; Osmolar Concentration; Fresh Water; Humic Substances; Electrolytes
PubMed: 37315858
DOI: 10.1016/j.chemosphere.2023.139194 -
Drug Discoveries & Therapeutics Jun 2024Dehydration is common in older adults and impacts their clinical outcomes. Chronic dehydration is especially important as it has been under-recognized. This scoping... (Review)
Review
Dehydration is common in older adults and impacts their clinical outcomes. Chronic dehydration is especially important as it has been under-recognized. This scoping review aimed to summarize the available definitions of chronic dehydration to identify gaps between each definition and discuss future research needs. Four databases (Pubmed, CINAHL, Cochrane Library, Science Direct) were systematically searched for peer-reviewed articles that clearly described the definition of chronic dehydration published from inception to June 8, 2023. Two researchers reviewed the articles independently, and any disagreement was solved upon discussion. We identified five articles with a wide range of subjects from children to older adults. Chronic dehydration was defined as a state of persistently elevated blood urea levels; weight loss ≥ 1% as a result of fluid loss; a ratio of blood urea nitrogen to creatinine > 20; serum osmolarity ≥ 295 mOsm/kg; and a dehydrated state lasting 72 hours or longer. The definition varied among studies, indicating the need to establish an international consensus on the definition of chronic dehydration.
Topics: Dehydration; Humans; Chronic Disease; Consensus; Weight Loss; Blood Urea Nitrogen; Osmolar Concentration; Creatinine
PubMed: 38658358
DOI: 10.5582/ddt.2024.01014 -
European Journal of Ophthalmology May 2024To demonstrate that intense pulsed light therapy (IPL) of the upper and lower eyelids with meibomian gland expression (MGX) is effective in improving dry eye disease due...
PURPOSE
To demonstrate that intense pulsed light therapy (IPL) of the upper and lower eyelids with meibomian gland expression (MGX) is effective in improving dry eye disease due to meibomian gland dysfunction (MGD).
METHODS
Patients with ocular discomfort (Ocular Surface Disease Index -OSDI- above 13) and signs of MGD were recruited. All patients underwent OSDI, visual acuity (VA), intraocular pressure, Schirmer test, meibography, non-invasive tear breakup time (NITBUT), slit-lamp examination (corneal and conjunctival staining, hyperemia, gland expressibility, and meibum quality), tear osmolarity and lipid layer thickness. IPL was performed with Optima IPL (Lumenis Ltd.) following a standardized protocol on upper and lower eyelids of both eyes, with inferior eyelid MGX. Patients received four sessions separated by two weeks each. Four weeks after, examinations were repeated.
RESULTS
160 patients (320 eyes) were included, of which 108 (67.5%) were women and mean age was 59.2 ± 15.08 (range 20-89). After four sessions, VA, OSDI, tear osmolarity, lipid layer thickness, NITBUT, hyperemia, corneal and conjunctival staining, gland expressibility, meibum quality, inferior eyelid Meiboscore and Schirmer test improved (all, p < 0.027). Changes in OSDI, initial and average NITBUT increased with dry eye disease severity (according to OSDI). Increased pre-treatment OSDI, hyperemia, corneal and conjunctival staining and Schirmer test were associated with an improvement in OSDI (all, p < 0.040). No adverse events were noted.
CONCLUSIONS
The combination of IPL on upper and lower eyelids with MGX is safe and effective for the treatment of MGD. Patients with severe dry eye disease present greater improvements.
Topics: Humans; Female; Meibomian Gland Dysfunction; Middle Aged; Male; Prospective Studies; Aged; Adult; Tears; Meibomian Glands; Aged, 80 and over; Intense Pulsed Light Therapy; Young Adult; Visual Acuity; Treatment Outcome; Dry Eye Syndromes; Eyelids; Osmolar Concentration; Intraocular Pressure
PubMed: 37671407
DOI: 10.1177/11206721231199121 -
Electrophoresis Apr 2024Understanding electrokinetic transport in nanochannels and nanopores is essential for emerging biological and electrochemical applications. The viscoelectric effect is...
Understanding electrokinetic transport in nanochannels and nanopores is essential for emerging biological and electrochemical applications. The viscoelectric effect is an important mechanism implicated in the increase of local viscosity due to the polarization of a solvent under a strong electric field. However, most analyses of the viscoelectric effect have been limited to numerical analyses. In this work, we present a set of analytical solutions applicable to the physical description of viscoelectric effects in nanochannel electrokinetic systems. To achieve such closed-form solutions, we employ the Debye-Hückel approximation of small diffuse charge layer potentials compared to the thermal potential. We analyze critical parameters, including electroosmotic flow profiles, electroosmotic mobility, flow rate, and channel conductance. We compare and benchmark our analytical solutions with published predictions from numerical models. Importantly, we leverage these analytical solutions to identify essential thermophysical and nondimensional parameters that govern the behavior of these systems. We identify scaling parameters and relations among surface charge density, ionic strength, and nanochannel height.
Topics: Electroosmosis; Viscosity; Nanotechnology; Microfluidic Analytical Techniques; Nanopores; Osmolar Concentration; Nanostructures
PubMed: 38350722
DOI: 10.1002/elps.202300204 -
Scientific Reports Aug 2023A common benchmark in the brain tissue mechanics literature is that the properties of acute brain slices should be measured within 8 h of the experimental animal being...
A common benchmark in the brain tissue mechanics literature is that the properties of acute brain slices should be measured within 8 h of the experimental animal being sacrificed. The core assumption is that-since there is no substantial protein degradation during this time-there will be no change to elastic modulus. This assumption overlooks the possibility of other effects (such as osmotic swelling) that may influence the mechanical properties of the tissue. To achieve consistent and accurate analysis of brain mechanics, it is important to account for or mitigate these effects. Using atomic force microscopy (AFM), tissue hydration and volume measurements, we find that acute brain slices in oxygenated artificial cerebrospinal fluid (aCSF) with a standard osmolarity of 300 mOsm/l experience rapid swelling, softening, and increases in hydration within the first 2 hours after slicing. Reductions in elastic modulus can be partly mitigated by addition of chondroitinase ABC enzyme (CHABC). Increasing aCSF osmolarity to 400 mOsm/l does not prevent softening but may hasten equilibration of samples to a point where measurements of relative elastic modulus are consistent across experiments.
Topics: Elastic Modulus; Brain; Microscopy, Atomic Force; Water; Time Factors; Female; Animals; Mice; Osmolar Concentration
PubMed: 37550376
DOI: 10.1038/s41598-023-40074-z -
PeerJ 2024Drought and salinity are the major abiotic stress factors negatively affecting the morphophysiological, biochemical, and anatomical characteristics of numerous plant... (Review)
Review
Drought and salinity are the major abiotic stress factors negatively affecting the morphophysiological, biochemical, and anatomical characteristics of numerous plant species worldwide. The detrimental effects of these environmental factors can be seen in leaf and stem anatomical structures including the decrease in thickness of cell walls, palisade and spongy tissue, phloem and xylem tissue. Also, the disintegration of grana staking, and an increase in the size of mitochondria were observed under salinity and drought conditions. Drought and salt stresses can significantly decrease plant height, number of leaves and branches, leaf area, fresh and dry weight, or plant relative water content (RWC%) and concentration of photosynthetic pigments. On the other hand, stress-induced lipid peroxidation and malondialdehyde (MDA) production, electrolyte leakage (EL%), and production of reactive oxygen species (ROS) can increase under salinity and drought conditions. Antioxidant defense systems such as catalase, peroxidase, glutathione reductase, ascorbic acid, and gamma-aminobutyric acid are essential components under drought and salt stresses to protect the plant organelles from oxidative damage caused by ROS. The application of safe and eco-friendly treatments is a very important strategy to overcome the adverse effects of drought and salinity on the growth characteristics and yield of plants. It is shown that treatments with plant growth-promoting bacteria (PGPB) can improve morphoanatomical characteristics under salinity and drought stress. It is also shown that yeast extract, mannitol, proline, melatonin, silicon, chitosan, -Tocopherols (vitamin E), and biochar alleviate the negative effects of drought and salinity stresses through the ROS scavenging resulting in the improvement of plant attributes and yield of the stressed plants. This review discusses the role of safety and eco-friendly treatments in alleviating the harmful effects of salinity and drought associated with the improvement of the anatomical, morphophysiological, and biochemical features in plants.
Topics: Stress, Physiological; Droughts; Plant Development; Bacteria; Salinity; Plants
PubMed: 38708356
DOI: 10.7717/peerj.17286 -
Molecules (Basel, Switzerland) Oct 2023Saponins are a large group of organic amphiphilic substances (surfactants) mainly extracted from herbs with biological activity, considered as one of the main...
Saponins are a large group of organic amphiphilic substances (surfactants) mainly extracted from herbs with biological activity, considered as one of the main ingredients in numerous remedies used in traditional medicine since ancient times. Anti-inflammatory, antifungal, antibacterial, antiviral, antiparasitic, antitumor, antioxidant and many other properties have been confirmed for some. There is increasing interest in the elucidation of the mechanisms behind the effects of saponins on different cell types at the molecular level. In this regard, erythrocytes are a very welcome model, having very simple structures with no organelles. They react to changing external conditions and substances by changing shape or volume, with damage to their membrane ultimately leading to hemolysis. Hemolysis can be followed spectrophotometrically and provides valuable information about the type and extent of membrane damage. We investigated hemolysis of erythrocytes induced by various saponin concentrations in hypotonic, isotonic and hypertonic media using measurements of real time and end-point hemolysis. The osmotic pressure was adjusted by different concentrations of NaCl, manitol or a NaCl/manitol mixture. Unexpectedly, at a fixed saponin concentration, hemolysis was accelerated at hypertonic conditions, but was much faster in NaCl compared to mannitol solutions at the same osmotic pressure. These findings confirm the colloid-osmotic mechanism behind saponin hemolysis with pore formation with increasing size in the membrane.
Topics: Humans; Hemolysis; Sodium Chloride; Saponins; Erythrocytes; Osmotic Pressure
PubMed: 37894578
DOI: 10.3390/molecules28207096 -
Environmental Microbiology Reports Dec 2023The transfer of toxic cyanobacterial Microcystis blooms from freshwater to estuaries constitutes a serious environmental problem worldwide that is expected to expand in...
The transfer of toxic cyanobacterial Microcystis blooms from freshwater to estuaries constitutes a serious environmental problem worldwide that is expected to expand in scale and intensity with anthropogenic and climate change. The formation and maintenance of Microcystis in colonial form is conditioned to the presence of extracellular polymeric substances (EPS). In this study, we attempted to better understand how the mucilaginous colonial form of Microcystis evolves under environmental stress conditions. In particular, we studied and compared the production and the composition of EPS fractions (attached and free) from natural colonies of a Microcystis bloom and from a unicellular M. aeruginosa strain under salinity and nutrient stress (representing a land-sea continuum). Our results highlighted a greater production of EPS from the natural colonies of Microcystis than the unicellular one under nutrient and combined stress conditions dominated by the attached form. In comparison to the unicellular Microcystis, EPS produced by the colonial form were characterized by high molecular weight polysaccharides which were enriched in uronic acids and hexosamines, notably for the free fraction in response to increased salinities. This complex extracellular matrix gives the cells the ability to aggregate and allows the colonial cyanobacterial population to cope with osmotic shock.
Topics: Microcystis; Extracellular Polymeric Substance Matrix; Salinity; Cyanobacteria; Polysaccharides
PubMed: 37697704
DOI: 10.1111/1758-2229.13200 -
Korean Journal of Ophthalmology : KJO Dec 2023To investigate the effects of humidity and temperature on dry eye disease (DED).
PURPOSE
To investigate the effects of humidity and temperature on dry eye disease (DED).
METHODS
A retrospective, clinic-based study was conducted on DED patients undergoing dry eye treatment. Patients were followed up at least twice, and symptoms and signs were evaluated using the Symptoms Assessment Questionnaire in Dry Eye (SANDE) score, tear secretion, tear film breakup time (TBUT), ocular staining score, and tear osmolarity. Mean humidity and temperature values for 1 week before ocular examinations were used as the environmental exposure level. The relationship between humidity and temperature, with DED clinical parameters was analyzed in single- and multi-environmental factor models.
RESULTS
The study included 33 patients with a mean age of 53.9 ± 12.2 years. The low humidity group showed significantly higher SANDE scores (p = 0.023) and tear osmolarity (p = 0.008), and the low temperature group had higher SANDE scores (p = 0.004), ocular staining scores (p = 0.036), and tear osmolarity (p < 0.001). In the linear mixed model, single factor analysis showed that an increase in humidity resulted in decreased SANDE scores (p = 0.043), and an increase in temperature led to a decrease in SANDE score (p = 0.007), ocular staining score (p = 0.007), and tear osmolarity (p = 0.012). In the multifactor analysis, changes in humidity had no significant effect on dry eye parameters, but an increase in temperature was significantly correlated with decreased SANDE score (p = 0.026), ocular staining score (p = 0.024), and tear osmolarity (p = 0.002).
CONCLUSIONS
Lower temperature led to aggravated symptoms and signs of DED and the effect of temperature on DED was more pronounced than humidity. Tear osmolarity was the most sensitive clinical parameter to be affected by climate factors in DED patients.
Topics: Humans; Adult; Middle Aged; Aged; Retrospective Studies; Temperature; Humidity; Dry Eye Syndromes; Tears; Osmolar Concentration
PubMed: 37899282
DOI: 10.3341/kjo.2023.0077