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Serum protein reference values in foals during the first year of life: comparison of chemical and electrophoretic methods.

Normal reference values for serum proteins of foals from birth to 1 year of age have been established. Chemical and electrophoretic/refractometric methods for total protein, albumin, total globulin and Albumin/Globulin (A/G ratio) have also been compared. The biuret total protein method and Bromcresol Green (BCG) method on the Technicon SMA 12/60 autoanalyzer were used and compared with total protein determined via refractometry and albumin determined by Cellulose Acetate (CA) electrophoresis/densitometry. Globulin and A/G ratios were calculated from the chemical method data and compared with that obtained electrophoretically. Total protein, albumin, total globulins and A/G ratios all were in agreement at all sample times studied. Data on the subfractionation of serum globulins via CA electrophoresis is also presented. Wide variations in alpha and beta globulin levels were noted among the foal sera early in life. As a result, two distinct populations of foals with respect to both globulin content and A/G ratio were identified. One of these populations (Group A) appeared to have obtained passive immunity more slowly than the other (Group B) animals. Comparison of these data with clinical cases of foals in which failure of passive transfer was a part suggests that the A/G ratio may be useful in assessing adequate colostral antibody levels in the newborn foal.

Journal Article↗

Analysis of transtracheal aspirates and pleural fluid from clinically healthy llamas (Llama glama).

Seventeen clinically healthy adult llamas were used to study the characteristics of transtracheal aspirates (TTA) and pleural fluid samples. Results of complete blood counts, fibrinogen determination and thoracic radiographs were within normal limits prior to sampling. Cytologic evaluation of TTA revealed the majority of cells were vacuolated macrophages (60-100%), with 0-40% neutrophils, and fewer lymphocytes (0-1%), eosinophils (0-3%), and ciliated respiratory epithelial cells (0-10%). In TTA from 10 of 17 llamas, neither aerobic nor anaerobic bacteria were isolated. Bacteria isolated in pure culture from TTA were similar to isolates found in clinically healthy animals of other species, and included Acinetobacter sp., Staphylococcus sp. and Bacillus sp. Results (mean +/- SD) of pleural fluid analyses were: total nucleated cell count 576 +/- 361/microliter; specific gravity 1.0133 +/- 0.002; glucose concentration 135.1 +/- 9.02 mg/dL; and lactate concentration 2.95 +/- 1.34 mg/dL. Pleural fluid total protein concentrations determined by refractometry ranged from < 2.5 to 3.5 g/dL. The refractive index ranged from 1.3396 to 0.0013. In pleural fluid, small lymphocytes were the predominant cell type.

Journal Article↗

Plasma biochemistry reference values of wild bonnethead sharks, Sphyrna tiburo.

BACKGROUND: Elasmobranchs (sharks, skates, and rays) are of commercial, sport, research, and exhibit importance, however, blood chemistry reference values have been determined for few of these species. OBJECTIVE: The purpose of this study was to establish plasma biochemistry and PCV reference values for wild bonnethead sharks (Sphyrna tiburo). METHODS: Heparinized blood samples were collected from 24 bonnethead sharks at the time of capture in trawl nets off the coast of South Carolina and Georgia. Weight, length, PCV, total solids (TS, by refractometry), and plasma biochemical analyses were done using standard techniques. Wilcoxon rank-sum and Kendall tau b tests were used to compare values by animal size, boat and sex; 1-way ANOVA was used to compare TS and total protein (TP) concentrations. RESULTS: Median (quartile; minimum-maximum) values were as follows: PCV 22% (22%, 26%; 17-28%), TS 6.3 (6.0, 6.8; 5.8-7.5) g/dL, total protein 2.9 (2.7, 3.4; 2.2-4.3) g/dL, albumin 0.4 (0.4, 0.4; 0.3-0.5) g/dL, globulins 2.6 (2.3, 3.0;1.9-3.8) g/dL, sodium 282 (279, 285;273-292) mmol/L, potassium 7.3 (6.4, 7.9; 5.7-9.2) mmol/L, chloride 290 (285, 296; 277-304) mmol/L, total CO2 3 (2, 4; 0-5) mmol/L, calcium 16.8 (16.2, 17.4;15.8-18.2) mg/dL, phosphorus 8.8 (7.5, 10.0; 5.9-12.7) mg/dL, urea nitrogen 1004 (986, 1028; 944-1068) mg/dL, creatinine <0.1 mg/dL, glucose 184 (165, 191; 155-218) mg/dL, aspartate aminotransferase 42 (33, 66; 15-132) U/L, lactate dehydrogenase <5 U/L, creatine kinase 82 (47, 233; 18-725) U/L, and osmolality 1094 (1078, 1111; 1056-1139) mOsm/kg. No differences based on sex were detected. TS and TP values were related by the fitted line TS = (1.006 X TP) + 3.318. CONCLUSION: Values reported here will be useful for evaluating the health status of bonnetheads in wild and captive research conditions and in exhibits.

Animals↗

Reference intervals for hematologic and biochemical constituents and protein electrophoretic fractions in captive common buzzards (Buteo buteo).

BACKGROUND: Increasing interest in wildlife care leads to the need for new tools to evaluate animal health. Laboratory investigations require reference intervals against which to compare the results obtained. For common buzzards, only a few studies have been performed to establish hematologic and biochemical reference intervals. OBJECTIVES: The aim of this work was to develop reference values for routine hematologic and biochemical constituents and protein electrophoretic fractions and evaluate possible seasonal differences in values for healthy common buzzards. METHODS: Heparinized blood samples were collected from 23 captive, clinically healthy common buzzards between February 2001 and June 2003. A CBC, routine biochemical analysis, and protein electrophoresis were performed. Data distribution was assessed and results from birds sampled in spring, summer, and winter were compared. Results from alternative methods for hemoglobin (Hgb; estimated as HCT / 3 vs spectrophotometry), total protein (biuret vs refractometry), and albumin (bromcresol green vs electrophoresis) concentrations also were compared. RESULTS: Reference intervals were calculated as 10-90th percentiles. In spring and summer, total WBC and heterophil counts, and urea, total protein, prealbumin, and beta- and gamma-globulins concentrations were significantly different from winter values. Results obtained by alternative methods for Hgb, total protein, and albumin concentrations were significantly different from those obtained by standard methods, although estimated and spectrophotometric Hgb values were significantly correlated. CONCLUSIONS: The reference values obtained in this study for hematologic and plasma biochemical constituents and their seasonal variation in healthy, captive common buzzards will be useful in the clinical evaluation of these birds in rehabilitation settings.

Animals↗

Hematology and plasma chemistry reference intervals for cultured shortnose sturgeon (Acipenser brevirostrum).

BACKGROUND: The shortnose sturgeon, Acipenser brevirostrum, is an imperiled species distributed along the Atlantic coast of North America. Interest in replenishing wild stocks with hatchery-reared fish has created a need for accurate hematologic and biochemical reference intervals to evaluate the health of both fish raised in aquaculture systems and fish in the wild. OBJECTIVES: The objective of this study was to generate hematologic and biochemistry reference intervals for healthy shortnose sturgeon. METHODS: Blood samples were collected in heparinized tubes from 77 shortnose sturgeon raised in flow-through aquaculture systems. Whole blood and plasma samples were analyzed for hematologic and biochemical variables using standard techniques. Reference intervals were calculated as the central 95% (percentile) of data. RESULTS: Hematologic reference intervals (n = 46) were as follows: PCV 26-46%, hemoglobin 5.7-8.7 g/dL, MCV 307-520 fL, MCH 65.9-107.1 pg, MCHC 15-30 g/dL, plasma proteins (refractometry) 2.8-6.0 g/dL, RBC count 0.65-1.09 x 10(6)/microL, total WBC count 28,376-90,789/microL, small lymphocytes 9063-56,656/microL, large lymphocytes 2122-10,435/microL, neutrophils 3758-33,592/microL, monocytes 0-7137/microL, eosinophils 0-1544/microL, thrombocyte-like cells 6863-23,046/microL, thrombocytes 32,205-122,179/microL, and neutrophil:lymphocyte ratio 0.068-1.026. Plasma chemistry reference intervals (n = 77) were as follows: total protein 2.7-5.3 g/dL, albumin 0.8-1.7 g/dL, globulins 1.8-3.7 mg/dL, creatinine 0-1.4 mg/dL, total bilirubin 0-0.1 mg/dL, alkaline phosphatase 47-497 U/L, aspartate aminotransferase 90-311 U/L, sodium 124-141 mmol/L, potassium 2.9-3.7 mmol/L, chloride 106-121 mmol/L, calcium 6.6-12.1 mg/dL, magnesium 1.6-2.3 mg/dL, phosphorus 5.1-8.1 mg/dL, glucose 37-74 mg/dL, cholesterol 42-133 mg/dL, and osmolality 232-289 mOsm/kg. CONCLUSION: Reference values reported here will be useful for the early detection, identification, and monitoring of disease and sublethal conditions in cultured shortnose sturgeon.

Animals↗

Some relations between dissolution rates and physical parameters of a drug in aqueous micellar solutions of a non-ionic surfactant.

Dissolution rates of salicylic acid from a constant surface area into a series of aqueous micellar polysorbate 20 solutions at pH 1-0 to 4-0 have been measured using two different methods; a stirred beaker and a rotating disc technique. The micellar molecular weight of polysorbate 20 has been obtained from light scattering and differential refractometry data and used with other independently determined physical data to calculate diffusion coefficients of the diffusing species. Linear multiple regression analysis was used to assess the dependence of drug dissolution rate on the diffusion coefficient and the viscosity of the dissolution medium.

Colloids↗

Sweet-sensitive protein from bovine taste buds: isolation and assay.

Using refractometry and ultraviolet-difference spectroscopy to indicate interaction between proteins and coinpounds of low molecular weight, we found a protein fraction in bovine tongue extracts that coinplexes sugars and saccharin. The strengths of the coinzplexes parallel the degrees of sweetness of the compounds, and the effects of pH upon formation of complexes parallel the effects of pH upon sensitivity of taste buds to sweet compounds in vivo.

Animals↗

A quantitative method for blood lipoproteins using cellulose acetate electrophoresis.

A rapid, inexpensive, and quantitative method is described for obtaining the levels of plasma very low, low, and high density lipoproteins using cellulose acetate electrophoresis and lipid assays without prior separation by ultracentrifuge or other techniques. It involves separation of the lipoproteins by cellulose acetate electrophoresis, followed by their identification with the ozone-Schiff reaction. The total lipoprotein concentration is estimated from the total plasma phospholipid, and the percentage of each component obtained by densitometric analysis of the stained electrophoretograms, using reflected light. For samples with a raised level of very low density lipoprotein, plasma triglyceride analysis is also required. The results obtained by the cellulose acetate electrophoresis method are in good agreement with those by the analytical ultracentrifuge and the preparative ultracentrifuge with refractometry. The theoretical assumptions on which the method is based have been shown to be valid.

Cellulose↗

Abnormal tear dynamics and symptoms of eyestrain in operators of visual display terminals.

OBJECTIVES: To clarify the relation between the prevalence of dry eye syndrome and subjective symptoms of asthenopia in visual display terminal (VDT) operators. METHOD: 722 VDT workers (242 subject workers with symptoms of asthenopia and 480 controls without such symptoms) without obvious organic ocular diseases received an ophthalmological examination consisting of refractometry and a tear function (phenol red thread) test. RESULTS: More than 30% of symptomatic workers were found to meet the criteria of dry eye, and the odds ratio compared with the controls was 4.61 (p < 0.001). This odds ratio was significantly greater than that obtained for refractive errors (2.31). CONCLUSIONS: Although this cross sectional study could not prove that dry eyes are the cause of asthenopia, the profound association of dry eyes with symptoms of asthenopia could be verified. It would be useful to carry out tear function tests in workers with symptoms of asthenopia.

Adult↗

A simple estimation of the immunoglobulin content of ewe colostrum.

Use of the optical refractometer in performing a rapid assessment of the immunoglobulin content of ovine colostrum under farm conditions was investigated. Refractometer readings were compared with total protein levels and with gamma-globulin levels, determined by the ZSTT, to assess the validity of the technique. In both cases correlation coefficients were high (0.98 and 0.79 respectively). Refractometry was shown to be a valid substitute for the ZSTT in studies on colostrum gamma-globulin levels.

Animals↗

Pulmonary microvascular permeability following E. coli endotoxin and hemorrhage.

The effects of hemorrhage and Escherichia coli endotoxin on vascular permeability in the lung were investigated in open-chest dogs. Systemic arterial, pulmonary artery, and left arterial pressures were monitored, and a 30-ml balloon catheter placed in the left atrium. An afferent to the left hilar lymph node was cannulated and lymph flow monitored. Lymph and plasma protein concentrations were measured by refractometry. The animals were divided into three groups: 1) a control group in which left atrial pressure was increased by inflation of the left atrial balloon; 2) a hemorrhagic shock group, bled to a systemic arterial pressure of 35-40 Torr until uptake of 20% of shed blood from the reservoir; and 3) an endotoxin shock group in which 2 or 4 mg/kg E. coli endotoxin was infused and left atrial pressure increased to 18 cmH2O for 2 hr. Permeability was determined by comparing the lymph/plasma protein ratios as a function of pulmonary lymph flow for the three groups at base line and increased left atrial pressures. There were no significant differences in lymph protein "wash down" between hemorrhage and control, and there was a minimal but significant difference between endotoxin and control groups. Postmortem extravascular lung water was not increased in the hemorrhage and endotoxin groups when compared to control. Therefore, there were no acute changes in lung vascular permeability within 2 hr after severe hemorrhage, but a minimal increase in permeability following endotoxin.

Analysis of Variance↗

[Refraction by atrophine cycloplegia].

A new method for refractive measurements with atropine cycloplegia was tested in 90 children with squint. Measurements were taken by an autorefractor (Canon R 10) 90 min after application of 2 atropine eye drops and after 3 days of receiving 1 atropine eye drop 3 times daily, i.e. 9 drops per eye. Results were also compared to conventional "objective" refractometry by means of a hand refractometer (Rodenstock PR 50). According to this method, the total refraction, spherical and cylindric power and the cylinder axis are in agreement with refractive data in 80-90% of the children after 3-day atropinization. The additional cycloplegic effect of atropine given for 3 days is only 0.5 dptr compared to the application of 2 drops on the first day. So for practical purposes the refractive data evaluated after 90-min atropinization can be used as a basis for the prescription of glasses.

Atropine↗

GABA, experimental myopia, and ocular growth in chick.

PURPOSE: To learn whether gamma-aminobutyric acid (GABA) participates in retinal mechanisms that influence refractive development. METHODS: White leghorn chicks, some of which wore a unilateral goggle to induce myopia, received daily intravitreal injections of agonists or antagonists to the major GABA receptor subtypes. Eyes were studied with refractometry, ultrasound, and calipers. Retinas of other chicks wearing unilateral goggles were assayed for GABA content. RESULTS: Antagonists to GABA(A) or GABA(A0r) (formerly known as GABA(C)) receptors inhibited form-deprivation myopia. GABA(A) antagonists showed greater inhibition of myopic growth in the equatorial than the axial dimension. A GABA(A0r) antagonist displayed parallel inhibition in the axial and equatorial dimensions. A GABA(A0r) agonist but not GABA(A) agonists altered the myopic refraction of goggled eyes. GABA(B) receptor antagonists, more so than an agonist, also slowed development of myopia, inhibiting axial growth more effectively than equatorial expansion of goggled eyes. When administered to nongoggled eyes, GABA(A) or GABA(A0r) agonists or antagonists also altered eye growth, chiefly stimulating it. Only a GABA(A) agonist induced a myopic refraction. Several of these agents stimulated eye growth in the axial, but not the equatorial, dimension. Retinal GABA content was slightly reduced in goggled eyes. CONCLUSIONS: GABA(A), GABA(A0r), and GABA(B) receptors modulate eye growth and refractive development. The anatomic effects of these drugs reinforce the notion that eye shape and not just eye size is regulated. A retinal site of action is consistent with the known ocular localizations of GABA and its receptors and with the altered retinal biochemistry in form-deprived eyes.

Animals↗

Characterization of carbonic anhydrase isozyme CA2, which is the CAH2 gene product, in Chlamydomonas reinhardtii.

From high-CO2 (5% CO2) grown unicellular green alga, Chlamydomonas reinhardtii, carbonic anhydrase (CA) was isolated by affinity chromatography and characterized. Isolated CA was identified as an isozyme (CA2) which is the product from the second gene CAH2 by peptide sequencing. The CA2 was inactivated by dithiothreitol. This treatment caused dissociation of CA2 into the large (38 kDa) and small subunits (4243 Da). The molecular mass of the CA2 holoenzyme measured by low-angle laser light-scattering photometry and precision differential refractometry combined with gel-filtration HPLC was 87.9 kDa. These results and gene structure indicate that CA2 is a heterotetramer consisting of two large and two small subunits linked by disulfide bonds like CA1, which is the CAH1 gene product. The specific activity of CA2 purified by anion-exchange HPLC was 3300 units per mg protein, which was approximately 1.6 times higher than that of CA1. Therefore, it was concluded that two structurally related isozymes, CA1 and CA2, are present in the wild type cells of C. reinhardtii and differentially regulated by the atmospheric CO2 concentration.

Amino Acid Sequence↗

Simultaneous measurement of refractive index and temperature based on a reflection-mode long-period grating and an intrinsic Fabry-Perot interferometer sensor.

We have demonstrated a single fiber probe for simultaneous measurement of external refractive index and temperature based on two interferometers: a reflection-mode long-period grating (LPG) for refractometry and an intrinsic Fabry-Perot interferometer (IFPI) for temperature measurement. Since the output signal of the combined structure is a superposition of signals produced by both sensors, which have different spatial frequencies, the original signals needed for the index and temperature measurements can be separated and recovered through digital filters.

Journal Article↗

Cocaine activates the renin-angiotensin system in pregnant rabbits and alters the response to ischemia.

The purpose of this study was to determine (1) if the acute in vivo administration of cocaine and the cocaine metabolite ecgonine methyl ester (EME) activates the renin-angiotensin system (RAS) and alters cardiovascular function during pregnancy and (2) whether heart function is decreased in rabbits chronically exposed to cocaine or EME in vivo. The acute in vivo effects on plasma renin activity (PRA) were examined when cocaine (2 mg/kg) or EME (2 mg/kg) was administered intravenously. Arterial blood samples were withdrawn for hormonal analysis. Arterial pressure was measured using a COBE CDX III transducer and a Micro-Med 100 blood pressure analyzer. Hematocrit was measured using a microcapillary technique and serum protein was analyzed using refractometry. In chronic cocaine and EME studies, cardiovascular function was monitored in rabbits that were chronically exposed to cocaine or EME via Alzet osmotic pumps (1.66 microg/h for 14 d) implanted subcutaneously. On d 14, the animal was euthanized, and the heart was removed and exposed to 15 min of global ischemia using the Langendorff method. Coronary flow and left ventricular pressure (LVP) were assessed. The acute administration of cocaine or EME increased PRA and mean arterial pressure (MAP) in pregnant rabbits within 5 min. Coronary flow and LVP were significantly lower in the cocaine and EME-treated rabbits than in vehicle female rabbits.

Anesthetics, Local↗

[Construction of a model eye for simulation of Purkinje reflections for determining the radii of curvature and the position of the crystalline lens].

UNLABELLED: Specular reflections at the optical interfaces of the eye, the Purkinje reflections, are used in physiologic optics and ophthalmology for biometric measurements. To date, there is no standard in the measurement of crystalline lens radii of curvature and position. To that end model eyes were designed. MATERIALS AND METHODS: The most important goal was to simulate the Purkinje reflections I, III, and IV, in the human eye as realistically as possible. The casing of the model eye was made of brass; the optical components were made from contact lens material. RESULTS: Several variants of components were manufactured to reproduce the range of variations in human eyes. By combining different components it was possible to vary the radii of curvature of the cornea and of the crystalline lens, axial separations, crystalline lens rotations and decentrations independently and reproducibly. First applications included devices for biometry of the crystalline lens (phacometry), validation of methods for eye alignment measurement, and refractometry. CONCLUSIONS: The properties of the specular reflections of the model eye are very close to the target values in human eyes. One of the advantages of the model eye is the compact design. This model eye is the first measuring standard for phakometry.

Anthropometry↗