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PubMed2001

Effects of propylene glycol drenching on energy balance, plasma glucose, plasma insulin, ovarian function and conception in dairy cows.

We postulated that daily drenching of propylene glycol to cows in early lactation would increase plasma glucose and insulin concentrations and improve fertility in postpartum cows. Thirty-six Holstein cows were assigned to treatment or control groups. Each treatment cow was given 500 ml of propylene glycol by drenching daily from 7 to 42 days of lactation. Blood samples for glucose, insulin, nonesterified fatty acids (NEFA), and plasma urea N were collected at 0, 30, and 90 min postdrenching once weekly during 1-6 weeks. Blood samples were collected for progesterone analysis and cows were palpated three times per week until 11 weeks to assess ovarian status. Propylene glycol did not affect dry matter intake (DMI), milk yield or energy balance in treatment cows. After drenching, propylene glycol increased (P<0.01) plasma glucose and insulin and decreased (P<0.01) NEFA; plasma urea N of the treatment group tended (P=0.07) to be higher than that of the control group through 90 min. Days to first service, days open, and services per conception were not different between groups. Conception rates to first insemination were 33% in the control group and 57% in treated cows, but these were not significantly different. First ovulation of treatment cows occurred earlier than that of control cows (32.3 versus 44.5 days, P=0.06) and the length of the first luteal phase was longer in treated cows (13.1 versus 7.3 days, P<0.05). These data are consistent with the hypothesis that insulin is important for normal ovarian function. During negative energy balance, treatment with propylene glycol, which induced small increases in plasma concentrations of insulin, prevented the short luteal phase characteristic of the first estrous cycle in control cows.

Animals↗
PubMed1996

Determination of plasma concentrations of SCH 44643 by a GC method and correlation of plasma concentration and anti-PAF activity in cynomolgus monkeys.

Inhibiting the action of platelet-activating factor (PAF) is a new therapeutic approach for the treatment of allergic disorders. SCH 44643 is a new orally-active antagonist of response to both PAF and histamine. This study was done to determine plasma drug concentrations using a GC method and to compare them to ex-vivo anti-PAF activity in the plasma of cynomolgus monkeys following a single oral (12.5 mg kg-1) administration. The GC method involved organic solvent extraction of monkey plasma followed by a GC analysis in a RTX-1 capillary column with a nitrogen/phosphorus detector. The method showed good precision (RSD < 8%) and accuracy (bias < 9%) with a limit of quantitation of 20 ng ml-1. The plasma profiles of SCH 44643 concentration and anti-PAF activity were very similar in each of the six monkeys. There was an excellent correlation (r = 0.9003) between anti-PAF activity and plasma concentration of SCH 44643, suggesting that the anti-PAF activity in cynomolgus monkeys was primarily due to unchanged SCH 44643, rather than its potential metabolite(s).

Administration, Oral↗
PubMed1982

[Plasma histamine assay in anaphylactoid reactions of the anesthetized subject. Effects of collection methods and plasma preparation on measured histamine].

Plasma histamine assay in man is indicated for the diagnosis of histamine release, as well as the elucidation of the mechanisms of adverse drug reactions, and the identification of clinical situations in anaesthesia and surgery where a pathological plasma histamine level may occur. Normal and pathological plasma histamine levels vary considerably in the literature. Data from various studies, especially one involving 300 patients in Heidelberg (G.F.R.), allow us to define the normal range for human plasma histamine as 0-1.0 ng . ml-1 . Values greater than 1 ng . ml-1 have to be considered as pathological. The problems related to blood collection and plasma preparation are considered here. Any judgement concerning the method described in the test must take into consideration our long experience of 15 years with it, its reliability in clinical conditions, its practicability, its relatively low cost, and finally, the absence of radioisotopes.

Adult↗
PubMed2000

Selenium supplementation of Chinese women with habitually low selenium intake increases plasma selenium, plasma glutathione peroxidase activity, and milk selenium, but not milk glutathione peroxidase activity.

Twenty-one pregnant women living in Xichang County, China, a selenium-deficient area, were divided into two groups and given either a placebo (n = 10) as yeast or selenium-enriched yeast tablets (n = 11) to provide 100 microg selenium per day. This supplementation was begun the last trimester of pregnancy and continued for 3 months after parturition. Plasma selenium levels and glutathione peroxidase (GPX) activity steadily declined in supplemented women, but a curvilinear response occurred in milk selenium and GPX activity in both supplemented and deficient women and in plasma selenium and GPX activity in deficient women. The milk selenium levels were higher in supplemented women but there were no differences in the milk GPX activity between the two groups of women. The plasma alpha-tocopherol concentrations declined after parturition in both groups but no differences were found between the two groups of women. Plasma thiobarbituric acid reactive substances declined in supplemented women but showed a curvilinear response in unsupplemented women, suggesting peroxidative stress in these women. GPX, selenium, and peroxidative responses in plasma and milk following parturition is advocated as a new method to assess selenium status of lactating women.

Journal Article↗
PubMed2002

Analysis of betamethasone in rat plasma using automated solid-phase extraction coupled with liquid chromatography-tandem mass spectrometry. Determination of plasma concentrations in rat following oral and intravenous administration.

A method is described for the determination of betamethasone in rat plasma by liquid chromatography-tandem mass spectrometry (LC-MS-MS). The analyte was recovered from plasma by solid-phase extraction and subsequently analyzed by LC-MS-MS. A Packard Multiprobe II, an automated liquid handling system, was employed for the preparation and extraction of a 96-well plate containing unknown plasma samples, standards and quality control samples in an automated fashion. Prednisolone, a structurally related steroid, was used as an internal standard. Using the described approach, a limit of quantitation of 2 ng/ml was achieved with a 50 microl aliquot of rat plasma. The described level of sensitivity allowed the determination of betamethasone concentrations and subsequent measurement of kinetic parameters of betamethasone in rat. Combination of automated plasma extraction and the sensitivity and selectivity of LC-MS-MS offers a valuable alternative to the methodologies currently used for the quantitation of steroids in biological fluids.

Administration, Oral↗
PubMed1980

Saliva and plasma levels and plasma protein binding of clofibrinic acid in uremic patients.

Clofibrinic acid in saliva and plasma and its plasma protein binding were determined in 18 patients with renal impairment after a single 2-gm dose of clofibrate. A weak but significant correlation (r2 = 0.378; p less than 0.02) between free plasma and saliva levels of clofibrinic acid was found. The free fraction of clofibrinic acid in plasma is higher (p less than 0.02) in long-term hemodialysis patients (0.0915 +/- 0.0141) than in nondialysis patients (0.0715 +/- 0.0143). During dialysis, 2 hemodialysis patients had a free fraction more than twice as high (mean, 0.2083) as that in the other hemodialysis patients who were studied on interdialysis days. These observations suggest that saliva pH determinations are essential for optimal interpretation of saliva to plasma level ratios of weakly acidic drugs and that, during hemodialysis, patients may temporarily be exposed to increased risks of drug toxicity due to rises in free concentrations of drugs.

Adult↗
PubMed2005

Low plasma selenium concentrations, high plasma human immunodeficiency virus load and high interleukin-6 concentrations are risk factors associated with anemia in adults presenting with pulmonary tuberculosis in Zomba district, Malawi.

BACKGROUND: Although anemia is common among adults with pulmonary tuberculosis and human immunodeficiency virus (HIV) infection in sub-Saharan Africa, the factors contributing to its pathogenesis have not been well characterized. OBJECTIVE: To characterize the antioxidant micronutrient status, interleukin-6 (IL-6) concentrations, and HIV load in relationship with anemia in adults with pulmonary tuberculosis. SETTING: Zomba district, Malawi. METHODS: Erythropoietin, IL-6, plasma HIV load, and markers of micronutrient status (hemoglobin (Hb), plasma concentrations of retinol, alpha-tocopherol, carotenoids, ferritin, zinc, and selenium) were measured in 500 adults who presented with pulmonary tuberculosis in Zomba Central Hospital, Malawi. RESULTS: Among 370 HIV-positive and 130 HIV-negative adults, the prevalence of anemia was 88 and 77%, respectively (P = 0.002), and moderate to severe anemia (Hb < 80 g/l) occurred in 30 and 15%, respectively (P = 0.001). Geometric mean IL-6 concentration was 21.1 pg/ml, with no difference between HIV-positive and -negative adults. The erythropoietin response to anemia was not different between adults with elevated IL-6 and those with lower IL-6 concentrations. In a multivariate logistic regression model, HIV load, and lower plasma selenium concentrations were associated with moderate to severe anemia. In a final multivariate linear regression model, IL-6, plasma HIV load, and plasma selenium concentrations were associated with Hb concentrations. CONCLUSION: This study suggests that low selenium concentrations, high HIV load, and high IL-6 concentrations are associated with anemia in adults with pulmonary tuberculosis in sub-Saharan Africa.

Adult↗
PubMed1976

Isolation of albumin from whole human plasma and fractionation of albumin-depleted plasma.

The dye Cibacron Blue F-3-GA was conjugated to Sepharose to provide an affinity column for serum albumin. Passage of whole human plasma through a column of Cibacron Blue-Sepharose results in the removal of approx. 98% of the albumin. The latter can be quantitatively recovered by desorption with NaSCN. Albumin-depleted plasma can be readily resolved into discrete fractions by a combination of conventional biochemical techniques. In particular, the resolution of plasma proteins with properties similar to those of native human plasma albumin can readily be accomplished by ion-exchange chromatography of the Sepharose-dye-treated plasma on DEAE-cellulose.

Ammonium Sulfate↗
PubMed1988

Depletion of plasma-membrane sphingomyelin rapidly alters the distribution of cholesterol between plasma membranes and intracellular cholesterol pools in cultured fibroblasts.

This study examines the relationship between cellular sphingomyelin content and the distribution of unesterified cholesterol between the plasma-membrane pool and the putative intracellular regulatory pool. The sphingomyelin content of cultured human skin fibroblasts was reduced by treatment of intact cells with extracellularly added neutral sphingomyelinase, and subsequent changes in the activities of cholesterol-metabolizing enzymes were determined. Exposure of fibroblasts to 0.1 unit of sphingomyelinase/ml for 60 min led to the depletion of more than 90% of the cellular sphingomyelin, as determined from total lipid extracts. In a time-course study, it was found that within 10 min of the addition of sphingomyelinase to cells, a dramatic increase in acyl-CoA:cholesterol acyltransferase activity could be observed, whether measured from the appearance of plasma membrane-derived [3H]cholesterol or exogenously added [14C]oleic acid, in cellular cholesteryl esters. In addition, the cholesteryl ester mass was significantly higher in sphingomyelin-depleted fibroblasts at 3 h after exposure to sphingomyelinase compared with that in untreated fibroblasts [7.1 +/- 0.4 nmol of cholesterol/mg equivalents of esterified cholesterol compared with 4.2 +/- 0.1 nmol of cholesterol/mg equivalents of cholesteryl ester in control cells (P less than 0.05)]. The sphingomyelin-depleted cells also showed a reduction in the rate of endogenous synthesis of cholesterol, as measured by incorporation of sodium [14C]acetate into [14C]cholesterol. These results are consistent with a rapid movement of cholesterol from sphingomyelin-depleted plasma membranes to the putative intracellular regulatory pool of cholesterol. This mass movement of cholesterol away from the plasma membranes presumably resulted from a decreased capacity of the plasma membranes to solubilize cholesterol, since sphingomyelin-depleted cells also had a decreased capacity to incorporate nanomolar amounts of [3H]cholesterol from the extracellular medium, as compared with control cells. These findings confirm previous assumptions that the membrane sphingomyelin content is an important determinant of the overall distribution of cholesterol within intact cells.

Acetates↗
PubMed1979

Plasma noradrenaline concentration in hypertensive and normotensive 40-year-old individuals: relationship to plasma renin concentration.

1. Forty-year-old individuals with mild essential hypertension, identified during a survey of a population born in 1936, were investigated. Forty-year-old normotensive subjects, drawn from the same population, served as a control group. 2. Plasma noradrenaline concentration and plasma renin concentration at rest supine and after acute stimulation, as induced by frusemide intravenously and ambulation, did not differ from reference values in the 40-year-old normotensive controls. In the hypertensive group a close correlation (r = 0.77, P less than 0.001) was found between plasma noradrenaline and plasma renin concentration after acute stimulation. 3. Sympathetic nerve activity, as defined by measurements of plasma noradrenaline, is normal in mild essential hypertension. Discrepancies described in the literature are probably related to a lack of comparability between hypertensive and normotensive study populations.

Adult↗
PubMed1987

Plasma atrial natriuretic peptide: its relationship to changes in sodium intake, plasma renin activity and aldosterone in man.

Plasma levels of immunoreactive atrial natriuretic peptide (IrANP), plasma renin activity, aldosterone and vasopressin were measured in 11 normotensive subjects on a low (10 mmol/day), a normal (150 mmol/day) and a high (350 mmol/day) sodium intake. Plasma levels of IrANP increased significantly with increasing dietary sodium intake with levels (means +/- SD) of 3.9 +/- 2.1 pg/ml on the fifth day of the low sodium diet, 6.1 +/- 3.4 pg/ml on the fifth day of the normal sodium diet and 11.4 +/- 4.6 pg/ml on the fifth day of the high sodium diet. Plasma renin activity and aldosterone decreased significantly with increasing sodium intake whereas plasma vasopressin was highest on the high sodium intake. These results suggest that the atrial peptides may be a new and important component in the overall control of sodium and water balance during increased sodium intake.

Adult↗
PubMed1989

Increased plasma atrial natriuretic factor and reduced plasma renin in patients with poorly controlled diabetes mellitus.

1. To investigate atrial natriuretic factor (ANF) and its relationship to the renin system in diabetes, we measured plasma immunoreactive ANF and plasma renin activity (PRA) in 27 non-ketotic diabetic patients without evidence of cardiac or overt renal disease, and compared them with 26 age- and sex-matched normal subjects. 2. Diabetic patients were divided prospectively into poor (PGC, n = 14) or moderate (MGC, n = 13) glycaemic control depending on their concurrent plasma glycohaemoglobin (HbA1) levels (greater than 9% or less than 9%, respectively). Plasma ANF was elevated in PGC diabetic patients (15.7 +/- 1.8 fmol/ml, mean +/- SEM) compared with MGC diabetics (9.9 +/- 0.8 fmol/ml, P less than 0.001) and normal subjects (10.1 +/- 1.3 fmol/ml, P less than 0.05). 3. In contrast, PRA was lower in the PGC diabetic patients (1.3 +/- 0.3 pmol of angiotensin 1 h-1 ml-1) compared with the other groups (2.5 +/- 0.5 and 2.1 +/- 0.2 pmol of angiotensin I h-1 ml-1, P less than 0.05). Diabetic groups had proportionally more patients with high prorenin values (over 30 ng h-1 ml-1) than the normal group, but there was no difference between the diabetic groups. 4. Among the diabetic patients, ANF was directly related to HbA1 (r = 0.49, P less than 0.005) and urinary albumin excretion (r = 0.40, P less than 0.02), and was inversely related to PRA (r = 0.36, P less than 0.04) and plasma creatinine (r = -0.42, P less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Atrial Natriuretic Factor↗
PubMed1994

Cold-induced increases in erythrocyte count, plasma cholesterol and plasma fibrinogen of elderly people without a comparable rise in protein C or factor X.

1. Six elderly (66-71 years) and six young (20-23 years) subjects (half of each group women) were cooled for 2 h in moving air at 18 degrees C to investigate possible causes of increased mortality from arterial thrombosis among elderly people in cold weather. Compared with thermoneutral control experiments, skin temperature (trunk) fell from 35.5 to 29.5 degrees C, with little change in core temperature. 2. Erythrocyte count rose in the cold from 4.29 to 4.69 x 10(12)/l, without a change in mean corpuscular volume, indicating a 14% or 438 ml decline in plasma volume; increased excretion of water, Na+ and K+ accounted for loss of only 179 ml of extracellular water. 3. Plasma cholesterol and fibrinogen concentrations rose in the elderly subjects from 4.90 mmol/l and 2.97 g/l (control) to 5.45 mmol/l and 3.39 g/l in the cold, and in the young subjects from 3.33 mmol/l and 1.84 g/l (control) to 3.77 mmol/l and 2.07 g/l in the cold. Increases were significant for the elderly subjects, the young subjects and the group as a whole, except for cholesterol in the young subjects, and all were close to those expected from the fall in plasma volume. 4. Plasma levels of Protein C and factor X did not increase significantly in the cold in the elderly subjects, young subjects, or the group as a whole. 5. The results suggest that loss of plasma fluid in the cold concentrates major risk factors for arterial thrombosis, while small molecules, including protective Protein C, redistribute to interstitial fluid.

Adult↗
PubMed1994

N-terminal atrial natriuretic peptide and atrial natriuretic peptide in human plasma: investigation of plasma levels and molecular circulating form(s) using radioimmunoassays for pro-atrial natriuretic peptide (31-67), pro-atrial natriuretic peptide (1-30) and atrial natriuretic peptide (99-126).

1. The aim of this study was to determine plasma levels of N-terminal atrial natriuretic peptide and atrial natriuretic peptide in normal subjects and in patients with essential hypertension, cardiac transplant and chronic renal failure, using radioimmunoassays directed towards the mid-portion pro-atrial natriuretic peptide (31-67) and pro-atrial natriuretic peptide (1-30) of the N-terminal atrial natriuretic peptide and atrial natriuretic peptide (99-126). The circulating form(s) of the immunoreactive N-terminal atrial natriuretic peptide in plasma extracts has been investigated using all three radioimmunoassays by means of gel filtration chromatography to further clarify the major immunoreactive molecular circulating form(s) of N-terminal atrial natriuretic peptide in man. 2. The plasma level (mean +/- SEM) of N-terminal pro-atrial natriuretic peptide (31-67) in the normal subjects was 547.2 +/- 32.7 pg/ml (n = 36) and was significantly elevated in patients with essential hypertension (730.2 +/- 72.3 pg/ml, P < 0.025, n = 39), in cardiac transplant recipients (3214.0 +/- 432.2 pg/ml, P < 0.001, n = 9) and in patients with chronic renal failure (3571.8 +/- 474.1 pg/ml, P < 0.001, n = 11). Plasma levels of N-terminal pro-atrial natriuretic peptide (1-30) and atrial natriuretic peptide were similarly elevated in the same patient groups when compared with the mean plasma values in the normal subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2003

An evaluation of the stability of factor VIII inhibitors in plasma and plasma dried on filter paper discs stored at room temperature.

The transportation of plasma specimens to specialized haemophilia centre laboratories for anti-factor VIII inhibitor titre determination is often necessary. The routine method of transporting frozen specimens on dry ice is limited by its cost and need for special handling. The present study was undertaken to evaluate the effect of storing specimens at room temperature on the FVIII inhibitor titre determinations using the Bethesda assay. Specimens stored both in liquid phase as well as adsorbed onto filter paper discs were studied. The results of the present study demonstrate that plasma specimens stored for up to 2 weeks at room temperature, either in liquid phase or adsorbed onto filter paper, yield equivalent measures of FVIII inhibitor titres using the Bethesda assay to plasma specimens stored frozen at -70 degrees C. Plasma specimens dried on filter paper discs and stored at room temperature offers a reliable, more practical and less expensive alternative to frozen plasma as a means of transport to specialized referral laboratories for analysis of anti-FVIII titres.

Autoantibodies↗
PubMed2001

Large volume apheresis of autologous plasma and preparation of autologous fibrin glue from the plasma.

Autologous blood transfusion (ABT) is useful for prevention of undesirable effects of allogeneic blood transfusion. In our hospital, not only autologous whole blood but also autologous red blood cells, autologous fresh frozen plasma (Auto-FFP), and autologous fibrin glue (Auto-FG) are routinely produced for surgical patients. The Auto-FG is prepared from plasma which is separated from manually collected whole blood. However, when a large volume of Auto-FG is required, the plasma obtained by an apheresis method may be useful. Therefore, a pilot study was conducted to determine whether a collection of 2 U (160 ml) of red blood cells (RBCs) and 400 ml of plasma at 1 apheresis is acceptable. We first performed the apheresis on healthy donors, and then applied for autologous blood donation. The apheresis is safe. The collected plasma is used for the production of Auto-FFP and Auto-FG. The remaining RBCs also are used for ABT. The preparation of Auto-FG is simple, and it is effective for the reduction of allogeneic fibrin glue.

Adult↗
PubMedDate not supplied

Antithrombin III in fresh frozen plasma, cryoprecipitate, and cryoprecipitate-depleted plasma.

Antithrombin III (AT III) is a plasma protein that inhibits several activated procoagulants. Hereditary disease or acquired conditions such as severe hepatic dysfunction, nephrotic syndrome and intravascular coagulation may be associated with reduced levels of AT III. Its replacement may be essential in controlling thrombosis. In order to determine the most effective form of replacement, we compared AT III biological activity and antigen levels in conventionally prepared fresh frozen plasma, cryoprecipitate and cryoprecipitate depleted plasma (CDP). Both the activity and antigen levels were comparable in all three products (approximately 100%) and AT III was not concentrated in cryoprecipitate. These results indicate that conventionally prepared CDP, fresh frozen plasma and cryoprecipitate contain equal quantities volume for volume of AT III. On this basis, all products are equally effective as therapy for AT III deficiency, but CDP and fresh frozen plasma are recommended as convenient sources of this factor.

Antithrombin III↗
PubMed1999

The TNF-alpha system in heart failure and after heart transplantation: plasma protein levels, mRNA expression, soluble receptors and plasma buffer capacity.

BACKGROUND: The two soluble tumour necrosis factor (TNF) receptors (sTNF-R1, sTNF-R2) can bind TNF-alpha, which is a cytokine with cardiodepressant properties. In heart failure and after heart transplantation, the TNF-alpha system is unbalanced, due to elevated levels of sTNF receptors. AIM: To assess the activity of the TNF-alpha system in patients with heart failure and after heart transplantation. METHODS: We measured TNF-alpha mRNA expression of peripheral blood mononuclear cells, plasma levels of TNF-alpha and sTNF reverse transcriptase receptors, using polymerase chain reaction and ELISA and performed a TNF-alpha binding capacity analysis, quantitating the buffer capacity of patients' plasma. RESULTS: In 11 patients with heart failure and in 15 cardiac allograft recipients, the TNF-alpha mRNA expression was comparable to controls. This level of mRNA was not accompanied by detectable TNF-alpha plasma levels. Significantly higher sTNF receptors levels were found in patients: ( P <0.001; ANOVA). The TNF-alpha binding capacity of patients' plasma was significantly increased, which led to decreased TNF-alpha recovery ( P<0.05). Both sTNF receptors showed a linear correlation with serum creatinine (sTNF-RI: r=0.92; sTNF-R2: r=0.82, P<0.001). CONCLUSIONS: The TNF-alpha mRNA expression and plasma levels show that the 'peripheral' TNF-alpha system is not activated. The high sTNF-receptors levels and their elevated TNF-alpha binding capacity, resulting in decreased TNF-alpha bioavailability, may contribute to an immunosuppressed state in these patients.

Adult↗