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Arctic Medical Research 1995Acid-base physiology has mainly focused on mechanisms that maintain normal, extracellular pH at a constant temperature. Usually it is the arterial blood which is... (Review)
Review
Acid-base physiology has mainly focused on mechanisms that maintain normal, extracellular pH at a constant temperature. Usually it is the arterial blood which is considered. As reliable pH meters became generally available in the 1950s it was observed that an arterial pH of about 7.39-7.42 was maintained remarkably constant in normal man and in mammals in general. This moderate degree of blood alkalosis is maintained by chemical buffering, by appropriate adjustment of the lung ventilation and by the kidneys. To measure pH intracellularly was more difficult, but not impossible, and over some time it became apparent that intracellular fluid was close to neutrality. pH values around 6.8 was found. This is a favorable state for retention of metabolites inside the cells. From an analysis by Davis (1) of the ionization constants of several hundred watersoluble biosynthetic intermediates one may argue that the ideal intracellular pH would occur near the neutrality of water where most of these compounds are ionized and thus captured within the cells, with little tendency to escape across the cell membrane. Apparently, if cells are to defend their neutrality and also to eliminate their acid metabolites and CO2, there must be a considerable transmembrane H+ gradient: The hydrogen ion concentration at neutrality is 160 nmol/L (pH 6.8) and that of blood 40 nmol/l (pH 7.4).
Topics: Acid-Base Equilibrium; Cold Temperature; Humans; Hypothermia; Male
PubMed: 8900837
DOI: No ID Found -
Annales Pharmaceutiques Francaises May 2017The intensive care department of the institution use drug solutions within higher concentration to avoid fluid overload. The purpose of the study is to prove the...
BACKGROUND
The intensive care department of the institution use drug solutions within higher concentration to avoid fluid overload. The purpose of the study is to prove the physical stability of different injectable drugs within high concentration (amiodarone 25mg/mL, isosorbide 0.60mg/mL, lorazepam 0.16mg/mL, noradrenalin 0.120 and 0.240mg/mL, salbutamol 0.06mg/mL and sodium valproate 12mg/mL) to ensure the patients safety.
METHODS
Five of 30 or 50mL polypropylene syringes were prepared for each solution under aseptic conditions and stored at room temperature. Immediately after the preparation (hour 0) and after 1, 4, 8, 24 and 48hours, 2mL of each solution were withdrawn from each syringe and placed in glass tubes to proceed to the stability test. All specimens were visually inspected in front of a black and of a white background and aliquots of each solution were centrifuged to proceed to microscopic inspection with a ten-fold magnification. The pH of each solution was measured with glass electrode pH-meter (Inolab level 1, WTW Weilhem, Germany with biotrode electrode, Hamilton, Bonaduz, Switzerland) and spectrophotometric measurements (Genesys 10 series, New-York, USA) were performed at three wavelengths (350, 410 and 550nm) to avoid the apparition of turbidity.
RESULTS
For all the drugs included in the study, there was no significant change in pH, no color change, no turbidity or opacity and no precipitation observed in the solutions during the storage at room temperature for 48hours. No microaggregates were detected by microscope neither revealed by a change of absorbance.
CONCLUSION
Within these limits, the preparations of amiodarone in 5% glucose polypropylene syringes and isosorbide, lorazepam, noradrenalin, salbutamol, valproate in 0.9% sodium chloride polypropylene syringes are physically stable at room temperature for 48hours. These results allow us to consider a study of chemical stability by high-performance liquid chromatography (HPLC).
Topics: Chromatography, High Pressure Liquid; Drug Stability; Hydrogen-Ion Concentration; Injections; Intensive Care Units; Pharmaceutical Solutions; Spectrophotometry, Ultraviolet; Syringes
PubMed: 28209389
DOI: 10.1016/j.pharma.2016.12.004 -
Diabetes Technology & Therapeutics 2001Glucose monitoring is essential for the successful management of gestational diabetes. The accuracy of glucose meters is typically determined over a much wider range of... (Comparative Study)
Comparative Study
Glucose monitoring is essential for the successful management of gestational diabetes. The accuracy of glucose meters is typically determined over a much wider range of glucose values than that commonly encountered in gestational diabetes. The objective of our study was to look at the accuracy of self-monitoring glucose meters in a clinic setting over a range of glucose values seen in gestational diabetes. We retrospectively analyzed 107 case records of subjects with gestational diabetes, each of whom had three simultaneous laboratory and glucose meter glucose tests. The results were compared using the performance goals that (1) all of glucose meters should have readings within 10% of the reference value and (2) the error grid analysis in the standard format and a modified version suitable for gestational diabetes. We also examined the range of the differences from the reference value. Nearly half of the values (47%) were in excess of 10% of the reference range (either above or below). Close to 15% were in excess of 20% difference from the reference range. Standard error grid analysis showed that 96% of the values fell within sections A of the error grid which are considered acceptable, and 100% fell within sections A and B, differences which are generally considered to have no major impact on care. The modified version of the error grid analysis demonstrated that 39% of the values were outside the acceptable range. Within subjects, a substantial number (26%) had a range of differences that exceeded 20% difference between each other. Although the meters give reasonable results that might be acceptable for general diabetes care, the results provide some cause for concern in the management of gestational diabetes. Given the need for precision in the setting of pregnancy particularly in making the decision of whether to start or withhold insulin therapy, caregivers need to be cognizant of these inaccuracies.
Topics: Blood Chemical Analysis; Blood Glucose; Blood Glucose Self-Monitoring; Diabetes, Gestational; Female; Humans; Laboratories, Hospital; Pregnancy; Regression Analysis; Reproducibility of Results; Retrospective Studies
PubMed: 11469713
DOI: 10.1089/152091501750220055 -
Schweizer Archiv Fur Tierheilkunde Sep 2009Portable blood glucose meters (PBGMs) are useful in the management of diabetes mellitus in cats. In the present study we compared the performance of two PBGMs: the... (Comparative Study)
Comparative Study
Portable blood glucose meters (PBGMs) are useful in the management of diabetes mellitus in cats. In the present study we compared the performance of two PBGMs: the AlphaTRAK (Abbott Animal Health, Maidenhead, England) specifically developed for dogs and cats, and the Ascensia ELITE (Bayer HealthCare, Zurich, Switzerland) developed for humans. Quality parameters, including precision and accuracy, were better for the AlphaTRAK meter compared to Ascensia ELITE. While the AlphaTRAK meter results did not differ from the reference method, results from the Ascensia ELITE were significantly (P<0.001) lower. The superior performance of the AlphaTRAK meter supports its use to monitor blood glucose levels in cats.
Topics: Animals; Blood Glucose; Blood Glucose Self-Monitoring; Cat Diseases; Cats; Diabetes Mellitus; Evaluation Studies as Topic; Postprandial Period; Reference Values; Reproducibility of Results; Sensitivity and Specificity
PubMed: 19722134
DOI: 10.1024/0036-7281.151.9.448 -
American Journal of Ophthalmology Jun 2017To determine the effect of dilating drops on strabismus measurements in adults.
PURPOSE
To determine the effect of dilating drops on strabismus measurements in adults.
DESIGN
Prospective cohort study.
METHODS
Patients aged 18 and older with strabismus underwent a standard evaluation of ocular motility, stereopsis, and ocular alignment with alternate prism cover test by a certified orthoptist. After pupil dilation with 2.5% phenylephrine and 1% tropicamide, ocular alignment was remeasured in primary gaze at 6 meters, at 1/3 meter, and at 1/3 meter with a +3.00 by a second certified orthoptist, masked to the previous measurements. The primary outcome was the mean difference in the angle of horizontal and vertical deviations after dilation in prism diopters.
RESULTS
A total of 55 patients were enrolled with a variety of diagnoses. For horizontal measurements the mean change was 0.54 prism diopters at 6 meters (95% confidence interval [CI] -0.36 to 1.43, P = .24), 1.67 prism diopters at 1/3 meter (95% CI -0.19 to 3.54, P = .08), and -0.05 prism diopters at 1/3 meter with a +3.00 add (95% CI -1.65 to 1.56, P = .95). The mean change in vertical deviation was 0.18 prism diopters at 6 meters (95% CI -0.19 to 0.56, P = .34), 0.57 prism diopters at 1/3 meter (95% CI 0-1.15, P = .05), and 0.47 prism diopters at 1/3 meter with a +3.00 add (95% CI -0.23 to 1.17, P = .18).
CONCLUSIONS
Pupil dilation does not meaningfully affect vertical or horizontal strabismus measurements in adults. Mild variability at near in younger patients is eliminated with the use of a +3.00 add.
Topics: Adolescent; Adult; Eye Movements; Female; Follow-Up Studies; Humans; Male; Middle Aged; Mydriatics; Ophthalmic Solutions; Prospective Studies; Pupil; Strabismus; Young Adult
PubMed: 28302533
DOI: 10.1016/j.ajo.2017.03.004 -
Animals : An Open Access Journal From... Jul 2023Intramammary infections, which cause mastitis, can increase treatment and labor costs, decrease milk production, and affect milk quality. Meters that measure quarter...
Intramammary infections, which cause mastitis, can increase treatment and labor costs, decrease milk production, and affect milk quality. Meters that measure quarter somatic cell count (SCC) could be used to make more informed dry cow therapy decisions. The objective of this study was to compare the RT-10 iPhone adapter (RT-10; Dairy Quality Inc., Newmarket, ON, Canada), DeLaval Cell Counter (DSCC; DeLaval, Gurnee, IL, USA), Porta Check Quick Test (PortaCheck, White City, OR, USA), California Mastitis Test (ImmuCell, Portland, ME USA), pH meter (Hanna Instruments, Smithfield, RI, USA), electrical conductivity meter (OHAUS, Parsippany, NJ, USA), and the dual laser infrared temperature thermometer (Klein Tools, Lincolnshire, IL, USA) for measuring SCC in individual Holstein mammary quarters in comparison to a reference standard, the Fourier Transform Spectrometer 600 Combi System (Combi; Bentley Instruments, Chaska, MN, USA). Meters were evaluated using 658 individual cow quarter samples and 100 bulk-tank samples to measure SCC. Individual quarter milk samples from 160 cows from four commercial dairy herds were collected just before dry off and tested within 4 h of collection. To test bulk-tank SCC, 100 bulk-tank milk samples (25 mL) were collected from UC Davis Veterinary Medicine Teaching and Research Milk Quality Lab. Meter SCC values were regressed on observed Combi SCC. Goodness of fit was then evaluated by partitioning the mean square predicted error (MSPE). For individual quarter SCC, RT-10 had the highest coefficient of determination (R = 0.86), lowest MSPE, and highest proportion of MSPE due to random variation (96%). Both the RT-10 and DSCC had the highest sensitivity and specificity for identifying quarter SCC above and below 200,000 cells/mL. For bulk-tank SCC, DSCC had the highest coefficient of determination (R = 0.45), lowest MSPE, and highest proportion of MSPE due to random variation (80%). The RT-10 and DSCC could be used to measure individual quarter SCC to determine which cows to treat at dry off potentially reducing antibiotic use.
PubMed: 37443967
DOI: 10.3390/ani13132169 -
The Onderstepoort Journal of Veterinary... Nov 2017Blood lactate is a predictor of mortality in critically ill humans and animals. Handheld lactate meters have the potential to be used in the field to evaluate the...
Blood lactate is a predictor of mortality in critically ill humans and animals. Handheld lactate meters have the potential to be used in the field to evaluate the condition of severely injured rhinoceroses but have not been compared with laboratory-based methods. Agreement between a handheld lactate meter and a laboratory method was assessed, as was the stability of rhino blood lactate in the anticoagulant sodium fluoride/potassium oxalate (fluoride/oxalate). Blood samples were obtained from 53 white rhinos that had been immobilised for management reasons. Lactate was measured by means of a handheld meter using whole blood in heparin (WBHEP), whole blood in fluoride/oxalate (WBFO) and fluoride/oxalate plasma (PFO). Results were recorded in both blood (BL) and plasma (PL) modes and compared to an established laboratory method for measuring plasma lactate. To assess the stability of lactate over time, blood lactate in fluoride/oxalate was measured on the handheld meter at intervals for up to 91 h. Agreement was best using WBFO in PL mode, with small bias (-0.16), tight 95% limits of agreement (LOA) (-1.46, 1.14) and a Pc (95% CI) of 0.97 (0.92, 0.99). The agreement was improved for all sample types when using the PL mode compared to the blood lactate (BL) mode. Blood lactate was stable in fluoride/oxalate for 91 h, with a mean change from baseline of 0.15 (-0.178, 0.478) mmol/L (mean, 95% CI). The handheld meter was found to be suitable for field use in white rhinos but provided more reliable results with the device in PL mode. Furthermore, rhino blood lactate was found to be stable in fluoride/oxalate for as long as 3 days.
Topics: Animal Husbandry; Animals; Biomarkers; Female; Hematology; Lactic Acid; Male; Perissodactyla; Reproducibility of Results; Veterinary Medicine
PubMed: 29227129
DOI: 10.4102/ojvr.v84i1.1399 -
PloS One 2021Meter is one of the core features of music perception. It is the cognitive grouping of regular sound sequences, typically for every 2, 3, or 4 beats. Previous studies...
Meter is one of the core features of music perception. It is the cognitive grouping of regular sound sequences, typically for every 2, 3, or 4 beats. Previous studies have suggested that one can not only passively perceive the meter from acoustic cues such as loudness, pitch, and duration of sound elements, but also actively perceive it by paying attention to isochronous sound events without any acoustic cues. Studying the interaction of top-down and bottom-up processing in meter perception leads to understanding the cognitive system's ability to perceive the entire structure of music. The present study aimed to demonstrate that meter perception requires the top-down process (which maintains and switches attention between cues) as well as the bottom-up process for discriminating acoustic cues. We created a "biphasic" sound stimulus, which consists of successive tone sequences designed to provide cues for both the triple and quadruple meters in different sound attributes, frequency, and duration. Participants were asked to focus on either frequency or duration of the stimulus, and to answer how they perceived meters on a five-point scale (ranged from "strongly triple" to "strongly quadruple"). As a result, we found that participants perceived different meters by switching their attention to specific cues. This result adds evidence to the idea that meter perception involves the interaction between top-down and bottom-up processes.
Topics: Acoustic Stimulation; Cues; Female; Humans; Male; Music; Pitch Perception; Sound; Young Adult
PubMed: 34460855
DOI: 10.1371/journal.pone.0256712 -
The Journal of Sports Medicine and... Dec 1991Much of the previous research efforts aimed at determining those physiological characteristics that contribute to distance running success have centered around distances...
Much of the previous research efforts aimed at determining those physiological characteristics that contribute to distance running success have centered around distances greater than 1500 meters with little attention to events such as the 800 meter run. Therefore, this investigation examined the relationship between selected physiological and body composition, characteristics and performance in an 800 meter run. Measurements of body composition, VO2max, running economy, and performance times for 100 and 300 meter dashes were obtained on 11 male track athletes. Stepwise multiple regression analysis was performed using 800 meter race time as the dependent variable. Although the combination of 300 and 100 meter run times, percent body fat, running economy and VO2 max as independent variables accounted for the greatest amount of total variance (r2 = .89), the additional variance explained by the model did not increase significantly (p greater than 0.05), when VO2max, percent body fat, and running economy were added to a model which contained 300 and 100 meter run time (r2 = .85) as the explanatory variables. These data offer additional support for the notion that much of the intramuscular ATP produce and utilized during an 800 meter run comes from anaerobic metabolic pathway.
Topics: Adult; Body Composition; Humans; Male; Oxygen Consumption; Regression Analysis; Running
PubMed: 1806725
DOI: No ID Found -
The Journal of Sports Medicine and... Jan 2023In sports, 10 m, 30 m and 40m events are used to test the athlete's acceleration ability, which depends on the coordination of physiological and neural function and can... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
In sports, 10 m, 30 m and 40m events are used to test the athlete's acceleration ability, which depends on the coordination of physiological and neural function and can be greatly improved through scientific training.
EVIDENCE ACQUISITION
This study conducted a systematic meta-analysis on the intermittent time of post-activation potentiation enhancement (PAPE) and the outcome measure was the sprint ability in 10 m and 30 m events. Data Sources : Web of Science, PubMed, ProQuest, Embase, Science Direct, Google Scholar, WanFang Data and CNKI. Study eligibility criteria : to qualify for inclusion in meta-analysis, the study must be: 1) healthy people (athletes, students); 2) randomized controlled trials; 3) Barbell squat was used to induce PAPE; 4) intervention period of at least 6 weeks; and 5) an outcome indicator of sprinting ability.
EVIDENCE SYNTHESIS
We used the inverse-variance random-effects model for meta-analyses. Effect sizes (standardized mean difference), calculated from measures of horizontally orientated performance, were represented by the standardized mean difference and presented alongside 95% confidence intervals (CI). A total of 9 studies including 141 participants, met the inclusion criteria. The sprint ability in 10 meters (ES=-0.03, P<0.0001) and 30 meters events (ES=-0.03, P=0.004) could be significantly improved when the intermittent time of PAPE was 4-8 min. When the intensity of the squat load was 85%1RM~100%1RM, compared with the intermittent time of 0-3min, 9-12min, and more than 13min, the sprint ability in 10 meters (ES=-0.04, P<0.0001) and 30 meters events (ES=-0.08, P=0.0001) was incredibly enhanced if the intermittent time was 4-8 minutes. Compared with college students, the sprint ability in 10-meter (ES=-0.03, P<0.0001) and 30-meter (ES=-0.04, P=0.001) events was significantly improved in athletes when the intermittent time of PAPE was 4-8 minutes. Compared with non-ball games, the sprint ability in 10 meters (ES=-0.04, P<0.0001) and 30 meters (ES=-0.09, P=0.0002) in ball games was significantly improved when the intermittent time of PAPE was 4-8 minutes.
CONCLUSIONS
Our meta-analysis indicated that when squats were used as the induction and the load intensity was 85% 1RM~100% 1RM, the sprint ability in 10-meter and 30-meter events could be significantly improved if the intermittent time was 4-8min. According to the analysis on different population, compared with college students and non-ball games, the 10-meter and 30-meter the sprint ability were significantly improved in athletes and ball games when the intermittent time was 4-8 minutes. Therefore, future research should focus on developing a reasonable combination of load stimulation and intermittent time according to the sprint ability to better induce PAPE.
Topics: Humans; Athletic Performance; Resistance Training; Acceleration; Athletes; Posture
PubMed: 35620952
DOI: 10.23736/S0022-4707.22.13502-4