Plasma Activity (plasma + activity)

Distribution by Scientific Domains


Selected Abstracts


Changes in the plasma activities of protein C and protein S during pregnancy

AUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 4 2000
Semra Oruç
Summary: The objective of the study was to determine the changes in the plasma activities of protein C and protein S that occur during normal pregnancy. In this prospective cross-sectional study, plasma activities of protein C and protein S were measured in 32 normal pregnant women in the first, second and third trimester and 6 weeks after delivery. There was a significant fall in protein C and protein S activities during normal pregnancy compared with the post-puerperal period. The activities of protein C and protein S also gradually decreased through-out pregnancy (p < 0.01). Increasing plasma volume during normal pregnancy and its dilutional effect might play some role in the low activities of protein S observed. The normal falls in protein S and protein C activities make it difficult to diagnose protein S and C deficiency during pregnancy. Based on our findings, if a woman has a thromboembolic event during pregnancy, testing for a definitive diagnosis of protein C or protein S deficiency or functional failure should be delayed until at least 6 weeks postpartum. [source]


Pharmacokinetics and residues in milk of oxytetra-cyclines administered parenterally to dairy goats

AUSTRALIAN VETERINARY JOURNAL, Issue 7 2001
R. RULE
Objective To determine for two commercial preparations of oxytetracycline (OTC) the pharmacokinetic behaviour, the presence of detectable milk residues and the penetration in milk of OTC administered by intravenous (IV) (conventional formulation [CF]) and intramuscular (IM) routes (CF and long-acting [LA] formulations) in goats producing milk. The effects of these formulations on plasma activity values of creatine kinase (CK) and lactate dehydrogenase (LDH) were also determined as indicators of tissue damage. Procedure Five healthy lactating goats producing 1.5 ± 0.5 L/d milk and weighing 56.0 ± 4.8 kg were used. Single doses of OTC chlorhydrate (CF) were administered (20 mg OTC/kg) by IV (Trial 1 IV) and IM (Trial 1 IM) routes and OTC dehydrate (LA) by the IM route. The same goats were first given IV CF, then IM CF followed by IM LA with 3 weeks between each treatment. Blood and milk samples were taken. The quantification of OTC was performed by HPLC and the plasma activities of CK and LDH enzymes were determined by spectrophotometry. The presence of OTC residues in milk was determined by a commercial reagent. The plasma pharmacokinetic parameters were calculated using a two-compartment model. Results Estimates of kinetic variables following IV administration were: Vss= 400.0 ± 120.0 mL/kg and CL= 110.0 ± 14.0 (mL/h)/kg. The tfi for IV= 3.0 ± 0.3 h; IM, CF = 10.5 ± 2.1 h and IM, LA = 15.1 ± 3.1 h. The concentration of OTC in milk at 48 h was: IV= 0.6 ± 0.4; IM CF= 1.1 ± 0.2 and at 72 h (IM LA)= 0.6 ± 0.1 ,g/mL and the penetration in milk of OTC was: IV= 70.0 ± 18.0; IM CF= 79.0 ± 14.0 and IM LA= 66.0 ± 6.0 %. The areas under the curve of CK and LDH activities in plasma were calculated by the trapezoidal method. Values of CK and LDH IM, LA were greater (P < 0.05) than those observed for IM, CF at 2 and 3 days after administration of the antibiotic. Finally, the bioavailability of OTC CF = 92.0± 22.0 and LA= 78.0 ± 23.0 % was suitable for its usage by the IM route in lactating goats. Conclusion Plasma concentration-time values of OTC administered parenterally in production dairy goats showed similar bioavailability for the two pharmaceutical preaprations. The presence of detectable residues in milk indicates that milk should not be used for human consumption for 2 and 3 days after administration of conventional and long-acting formulations, respectively. The increments in CK and LDH activities after the IM administration of LA are consistent with the presence of tissue damage provoked by the pharmaceutical preparations at the injection site. [source]


Plasma antioxidative activity during atorvastatin and fluvastatin therapy used in coronary heart disease primary prevention

FUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 1 2004
Jan Kowalski
Abstract We estimated the effect of atorvastatin and fluvastatin on plasma antioxidative activity used in coronary heart disease (CHD) primary prevention. Anti-oxidative activity of blood plasma was determined by Bartosz et al. method [Curr. Top. Biophys. (1998)22:11,13], based on reduction of preformed cation radical of 2,2,azinobis(3-ethylbenzothiazoline-6-sulphonic acid) by blood plasma. The study comprised 35 patients with CHD risk who were randomly divided into two groups. The atorvastatin group comprised 17 patients who were administered the drug orally in a daily dose of 10 mg and the fluvastatin group consisted of 18 patients on an oral dose of 40 mg once daily. The control group comprised 12 healthy subjects with no drug administration. Blood samples were collected from cubital vein before and after 6-week therapy. Significantly (P < 0.05) increased , in comparison with the initial values , antioxidative activity of blood plasma was found in atorvastatin and fluvastatin groups after 6-week therapy. Moreover, the increase in antioxidative plasma activity in atorvastatin group was significantly higher in comparison with the fluvastatin group. The results of our study have demonstrated that atorvastatin and fluvastatin have an additional mechanism independent of the effect on cholesterol concentration. Thus, we presume that administration of these statins in CHD risk patients may have a beneficial effect. [source]


Familial multiple coagulation factor deficiencies , chance associations and distinct clinical disorders

HAEMOPHILIA, Issue 1 2009
P. J. ROBSON
Summary., The familial multiple coagulation factor deficiencies (FMCFDs) are a group of rare haemostatic disorders of genetic origin in which there is reduced plasma activity of more than one coagulation factor. FMCFDs may arise from co-incidental inheritance of separate coagulation factor deficiencies or from a single genetic or cytogenetic defect. All the FMCFDs present significant challenges in diagnosis and management yet there is little systematic evidence with which to guide clinical practice. This review summarizes the historical literature that describes the FMCFDs and introduces a refined classification of these disorders. The clinical and laboratory characteristics of the most common FMCFDs are considered in detail. [source]


Aldosterone Excess or Escape: Treating Resistant Hypertension

JOURNAL OF CLINICAL HYPERTENSION, Issue 5 2009
Samira Ubaid-Girioli MD
Aldosterone excess or "escape" can occur after treatment with medications that block the renin-angiotensin-aldosterone system or in undiagnosed primary aldosteronism. Spironolactone is thought to be an important addition to resistant hypertension (RH) treatment. In this study, resistant (RH) and controlled (CH) hypertensives and normotensive patients were submitted to echocardiography, flow-mediated vasodilation, carotid intima-media wall thickness studies, renin plasma activity, and aldosterone plasma levels and plasma and urinary sodium and potassium concentrations at baseline (pre-spironolactone phase). Subsequently, for only RH and CH groups, 25 mg/d spironolactone was added to preexisting treatments over 6 months. Afterwards, these parameters were reassessed (post-spironolactone phase). The RH and CH groups achieved reductions in blood pressure (P<.001), decreases in left ventricular hypertrophy (P<.001), improved diastolic function (Kappa index RH: 0.219 and Kappa index CH: 0.392) and increases in aldosterone concentrations (P<.05). The RH group attained improved endothelium-dependent (P<.001) and independent (P=.007) function. Optimized RH treatment with spironolactone reduces blood pressure and improves endothelial and diastolic function and left ventricular hypertrophy despite the presence of aldosterone excess or escape. [source]


Antiangiogenic plasma activity in patients with systemic sclerosis

ARTHRITIS & RHEUMATISM, Issue 10 2007
Mary Jo Mulligan-Kehoe
Objective Systemic sclerosis (SSc; scleroderma) is a systemic connective tissue disease with an extensive vascular component that includes aberrant microvasculature and impaired wound healing. The aim of this study was to investigate the presence of antiangiogenic factors in patients with SSc. Methods Plasma samples were obtained from 30 patients with SSc and from 10 control patients without SSc. The samples were analyzed for the ability of plasma to affect endothelial cell migration and vascular structure formation and for the presence of antiangiogenic activity. Results Exposure of normal human microvascular dermal endothelial cells to plasma from patients with SSc resulted in decreased cell migration (mean ± SEM 52 ± 5%) and tube formation (34 ± 6%) compared with that in plasma from control patients (P < 0.001 for both). SSc plasma contained 2.9-fold more plasminogen kringle 1,3 fragments (angiostatin) than that in control plasma. The addition of angiostatin to control plasma resulted in inhibition of endothelial cell migration and proliferation similar to that observed in SSc plasma. In vitro studies demonstrated that granzyme B and other proteases contained in T cell granule content cleave plasminogen and plasmin into angiostatin fragments. Conclusion Plasminogen conformation in patients with SSc enables granzyme B and granule content protease to limit the proangiogenic effects of plasmin and increase the levels of antiangiogenic angiostatin. This increase in angiostatin production may account for some of the vascular defects observed in patients with SSc. [source]


Ozonated Autohemotherapy in Patients on Maintenance Hemodialysis: Influence on Lipid Profile and Endothelium

ARTIFICIAL ORGANS, Issue 2 2004
Leszek Tylicki
Abstract:, Ozonated autohemotherapy (O3-AHT) is used in the treatment of atherosclerotic ischemia of lower limbs (AILL). The impact of ozone on serum lipids and endothelium injury is of particular interest since these factors are important in the development of atherosclerotic lesions. To evaluate this issue, a prospective, placebo-controlled study was designed. Twelve hemodialyzed subjects with AILL received autohemotherapy with oxygen as a control followed by O3-AHT with ozone concentration of 50 µg/ml. Serum lipids and plasma activity of von Willebrand factor (vWF) were measured. After O3-AHT, total cholesterol significantly decreased compared to the baseline (,8.34%) [P < 0.01]. LDL cholesterol was also significantly lower than the initial value (,17.71%) [P < 0.001]. No significant changes in the activity of vWF were found after the first session of O3-AHT and after all nine sessions of O3-AHT. The study demonstrated that O3-AHT did not affect deleteriously the endothelium in patients with chronic renal failure on maintenance hemodialysis. It ,may stimulate beneficial changes in serum lipid profile manifesting as,,a, decrease ,in the total- and LDL-cholesterol ,levels. [source]