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Acta Obstetricia Et Gynecologica... Aug 2001The objective of this study was to test the hypothesis that maternal plasma, cord plasma and placental tissue lipid peroxidation products are increased and antioxidants...
BACKGROUND
The objective of this study was to test the hypothesis that maternal plasma, cord plasma and placental tissue lipid peroxidation products are increased and antioxidants are decreased in women with pre-eclampsia.
METHODS
Placenta, maternal and cord plasma were collected at delivery from 29 normal, 21 pre-eclamptic and six eclamptic women. Plasma was collected from 21 non-pregnant matched controls. The analyses were measured by HPLC and colorimetric assay.
RESULTS
Plasma maternal concentrations of uric acid, LPO, MDA, ascorbic acid, vitamin E and cholesterol were not significantly different in pre-eclampsia as compared with normal pregnancy. Plasma concentrations of ascorbic acid and vitamin E were not significantly different in normal pregnancy as compared with the non-pregnant controls. Cord plasma concentrations of MDA were significantly higher in eclampsia (1.16+/-0.26 micromol/l) as compared with normal pregnancy (0.79+/-0.05 micromol/l, p<0.02) and pre-eclampsia (0.83+/-0.05 micromol/l, p<0.05). Cord plasma concentrations of vitamin E were significantly higher in eclampsia (21.3+/-7.5 micromol/l) as compared with normal pregnancy (10.2+/-1.1 micromol/l, p<0.01) and pre-eclampsia (10.4+/-1.8 micromol/l, p<0.04). Placental concentrations of LPO, MDA and ascorbic acid were not significantly different in pre-eclampsia as compared with normal pregnancy. Plasma cord concentrations of LPO and placental concentrations of vitamin E were undetected for normal pregnant, pre-eclamptic and eclamptic women respectively. Uric acid concentrations were significantly increased in eclampsia as compared with the non-pregnant controls (p<0.0001), normal pregnant controls (p<0.0001) and pre-eclampsia (p<0.008).
CONCLUSIONS
The findings in this study do not show any evidence of deficiency in the maternal protective antioxidant systems or increased production of lipid peroxidation products, LPO and MDA in African women with pre-eclampsia as compared with normal pregnancy. However, there was evidence of increased cord plasma concentrations of MDA and vitamin E in eclampsia as compared with normal pregnancy and pre-eclampsia. The placenta may be effective in removing MDA. The antioxidant uric acid serves as a protective role whilst the antioxidant and oxidant capacity in the different study groups remained unchanged.
Topics: Adolescent; Adult; Ascorbic Acid; Black People; Case-Control Studies; Cholesterol; Eclampsia; Female; Fetal Blood; Humans; Lipid Peroxides; Malondialdehyde; Oxidative Stress; Placenta; Pre-Eclampsia; Pregnancy; Pregnancy Trimester, Third; Vitamin E
PubMed: 11531614
DOI: 10.1034/j.1600-0412.2001.080008719.x -
The Journal of Clinical Endocrinology... Apr 1999Sulfation is an important pathway of thyroid hormone metabolism that facilitates the degradation of the hormone by the type I iodothyronine deiodinase, but little is...
Sulfation is an important pathway of thyroid hormone metabolism that facilitates the degradation of the hormone by the type I iodothyronine deiodinase, but little is known about which human sulfotransferase isoenzymes are involved. We have investigated the sulfation of the prohormone T4, the active hormone T3, and the metabolites rT3 and 3,3'-diiodothyronine (3,3'-T2) by human liver and kidney cytosol as well as by recombinant human SULT1A1 and SULT1A3, previously known as phenol-preferring and monoamine-preferring phenol sulfotransferase, respectively. In all cases, the substrate preference was 3,3'-T2 >> rT3 > T3 > T4. The apparent Km values of 3,3'-T2 and T3 [at 50 micromol/L 3'-phosphoadenosine-5'-phosphosulfate (PAPS)] were 1.02 and 54.9 micromol/L for liver cytosol, 0.64 and 27.8 micromol/L for kidney cytosol, 0.14 and 29.1 micromol/L for SULT1A1, and 33 and 112 micromol/L for SULT1A3, respectively. The apparent Km of PAPS (at 0.1 micromol/L 3,3'-T2) was 6.0 micromol/L for liver cytosol, 9.0 micromol/L for kidney cytosol, 0.65 micromol/L for SULT1A1, and 2.7 micromol/L for SULT1A3. The sulfation of 3,3'-T2 was inhibited by the other iodothyronines in a concentration-dependent manner. The inhibition profiles of the 3,3'-T2 sulfotransferase activities of liver and kidney cytosol obtained by addition of 10 micromol/L of the various analogs were better correlated with the inhibition profile of SULT1A1 than with that of SULT1A3. These results indicate similar substrate specificities for iodothyronine sulfation by native human liver and kidney sulfotransferases and recombinant SULT1A1 and SULT1A3. Of the latter, SULT1A1 clearly shows the highest affinity for both iodothyronines and PAPS, but it remains to be established whether it is the prominent isoenzyme for sulfation of thyroid hormone in human liver and kidney.
Topics: Adult; Humans; Isoenzymes; Kinetics; Substrate Specificity; Sulfotransferases
PubMed: 10199779
DOI: 10.1210/jcem.84.4.5590 -
Journal of Dairy Science Jun 2010The aim of this study was to determine the nucleoside and nucleotide content in ovine and caprine milks at the colostral, transitional, and mature stages of lactation.... (Comparative Study)
Comparative Study
The aim of this study was to determine the nucleoside and nucleotide content in ovine and caprine milks at the colostral, transitional, and mature stages of lactation. Samples from 18 dairy sheep and 18 dairy goats were collected at 1, 2, 3, 4, 5, and 15 d postpartum. Separation and quantitation of the 5'-nucleotides (NT) and the nucleosides (NS) was performed by reverse phase HPLC. For each compound measured, considerable interindividual variation was recorded in both species of milk. The total NS content ranged from 57 to 132 micromol/L and from 54 to 119 micromol/L in ovine and caprine milk, respectively. The major NS identified in both species of milk was uridine, representing more than 60% of the total NS pool. The mean levels of inosine and guanosine were comparable between ewe and goat milk. Instead, the mean level of cytidine across the sampling period was much higher in ewe milk (11.9 micromol/L compared with 4.5 micromol/L in goat milk) and exhibited a peak value on the fourth day of lactation. The adenosine content was at least 3-fold higher in caprine milk compared with its ovine counterpart. The total NS and orotic acid contents did not differ significantly between the 2 species. However, in the case of total NT content, interspecies differences were significant, with NT levels ranging from 294 to 441 micromol/L in ovine milk and from 166 to 366 micromol/L in caprine milk. The NT content in colostrum (1-3 d) of both species was higher than in mature milk (15 d), and uridine monophosphate was the dominant NT in all samples.
Topics: Adenosine; Adenosine Monophosphate; Animals; Cattle; Chromatography, High Pressure Liquid; Colostrum; Cytidine; Cytidine Monophosphate; Female; Goats; Guanosine; Inosine; Lactation; Milk; Nucleosides; Nucleotides; Uridine; Uridine Monophosphate
PubMed: 20494137
DOI: 10.3168/jds.2009-2836 -
Acta Pharmacologica Sinica Oct 2009To evaluate the impact of extracellular and intracellular Ca2+ on contractions induced by ethanol in smooth muscle.
AIM
To evaluate the impact of extracellular and intracellular Ca2+ on contractions induced by ethanol in smooth muscle.
METHODS
Longitudinal smooth muscle strips were prepared from the gastric fundi of mice. The contractions of smooth muscle strips were recorded with an isometric force displacement transducer.
RESULTS
Ethanol (164 mmol/L) produced reproducible contractions in isolated gastric fundal strips of mice. Although lidocaine (50 and 100 micromol/L), a local anesthetic agent, and hexamethonium (100 and 500 micromol/L), a ganglionic blocking agent, failed to affect these contractions, verapamil (1-50 micromol/L) and nifedipine (1-50 micromol/L), selective blockers of L-type Ca2+ channels, significantly inhibited the contractile responses of ethanol. Using a Ca(2+)-free medium nearly eliminated these contractions in the same tissue. Ryanodine (1-50 micromol/L) and ruthenium red (10-100 micromol/L), selective blockers of intracellular Ca2+ channels/ryanodine receptors; cyclopiazonic acid (CPA; 1-10 mumol/L), a selective inhibitor of sarcoplasmic reticulum (SR) Ca(2+)-ATPase; and caffeine (0.5-5 mmol/L), a depleting agent of intracellular Ca2+ stores, significantly inhibited the contractile responses induced by ethanol. In addition, the combination of caffeine (5 mmol/L) plus CPA (10 micromol/L), and ryanodine (10 micromol/L) plus CPA (10 micromol/L), caused further inhibition of contractions in response to ethanol. This inhibition was significantly different from those associated with caffeine, ryanodine or CPA. Furthermore the combination of caffeine (5 mmol/L), ryanodine (10 micromol/L) and CPA(10 micromol/L) eliminated the contractions induced by ethanol in isolated gastric fundal strips of mice.
CONCLUSION
Both extracellular and intracellular Ca2+ may have important roles in regulating contractions induced by ethanol in the mouse gastric fundus.
Topics: Animals; Caffeine; Calcium; Calcium Channel Blockers; Calcium-Transporting ATPases; Dose-Response Relationship, Drug; Drug Interactions; Ethanol; Female; Gastric Fundus; Indoles; Isometric Contraction; Male; Mice; Muscle Contraction; Muscle, Smooth; Nifedipine; Ruthenium Red; Ryanodine; Ryanodine Receptor Calcium Release Channel; Sarcoplasmic Reticulum; Verapamil
PubMed: 19749788
DOI: 10.1038/aps.2009.123 -
American Journal of Physiology.... Jun 2006Strong inward rectifier potassium channels are expressed by some vascular smooth muscle cells and facilitate K+-induced hyperpolarization. Using whole cell patch clamp...
Strong inward rectifier potassium channels are expressed by some vascular smooth muscle cells and facilitate K+-induced hyperpolarization. Using whole cell patch clamp of isolated descending vasa recta (DVR), we tested whether strong inward rectifier K+ currents are present in smooth muscle and pericytes. Increasing extracellular K+ from 5 to 50 and 140 mmol/l induced inward rectifying currents. Those currents were Ba2+ sensitive and reversed at the K+ equilibrium potential imposed by the electrode and extracellular buffers. Ba2+ binding constants in symmetrical K+ varied between 0.24 and 24 micromol/l at -150 and -20 mV, respectively. Ba2+ blockade was time and voltage dependent. Extracellular Cs+ also blocked the inward currents with binding constants between 268 and 4,938 micromol/l at -150 and -50 mV, respectively. Ba2+ (30 micromol/l) and ouabain (1 mmol/l) depolarized pericytes by an average of 11 and 24 mV, respectively. Elevation of extracellular K+ from 5 to 10 mmol/l hyperpolarized pericytes by 6 mV. That hyperpolarization was reversed by Ba2+ (30 micromol/l). We conclude that strong inward rectifier K+ channels and Na+-K+-ATPase contribute to resting potential and that KIR channels can mediate K+-induced hyperpolarization of DVR pericytes.
Topics: Animals; Barium; Capillaries; Cesium; Electrophysiology; In Vitro Techniques; Kidney Medulla; Membrane Potentials; Ouabain; Patch-Clamp Techniques; Pericytes; Potassium; Potassium Channels, Inwardly Rectifying; Rats; Rats, Sprague-Dawley
PubMed: 16439665
DOI: 10.1152/ajpregu.00877.2005 -
Acta Pharmacologica Sinica Aug 2001To investigate the effect of melittin (Mel) on papillary muscles of guinea pigs.
AIM
To investigate the effect of melittin (Mel) on papillary muscles of guinea pigs.
METHODS
Contraction of papillary muscles were examined by conventional method and action potentials (AP) were recorded by standard glass microelectrode technique.
RESULTS
Mel (0.5, 3 micromol/L) significantly increased the contractility of guinea pig papillary muscles while 5 micromol/L exerted dual action with a transient decrease followed by an increase of the contractility. Mel shortened the functional refractory period (FRP) at concentrations of 0.5, 3, and 5 micromol/L and increased the automaticity induced by adrenaline (Adr) at 3 and 5 micromol/L. Mel shifted the duration-intensity curve upward at 3 micromol/L. It shortened the action potential duration (APD) of fast action potential (FAP), decreased the action potential amplitude (APA) and resting potential (RP) at 0.5 and 3 micromol/L. As to slow action potential (SAP), Mel 0.8 micromol/L shortened APD20 and APD50, and decreased APA and RP.
CONCLUSION
Mel increased the contractility and automaticity of papillary muscles, shortened the FRP, decreased the excitability, shortened the APD, and decreased APA and RP of AP.
Topics: Action Potentials; Animals; Female; Guinea Pigs; In Vitro Techniques; Male; Melitten; Microelectrodes; Myocardial Contraction; Papillary Muscles; Refractory Period, Electrophysiological
PubMed: 11749840
DOI: No ID Found -
The Journal of Nutrition Jun 2007Hyperphenylalaninemia (HPA) is the most frequently inherited disorder of amino acid metabolism (prevalence 1:10,000). In France, a nationwide neonatal screening was...
Hyperphenylalaninemia (HPA) is the most frequently inherited disorder of amino acid metabolism (prevalence 1:10,000). In France, a nationwide neonatal screening was organized in 1978 to control its efficacy and patient follow-up. Phenylketonuria (PKU) was diagnosed in 81.6% of screened patients, the remaining affected with either non-PKU HPA (17.2%) or with cofactor deficiency (1.1%). French guidelines were established to specify the minimal diagnosis procedures and optimal treatment of patients. A low-phenylalanine diet must be started within the first days of life for all newborns whose blood phenylalanine levels are above 10 mg/dL (600 micromol/L). The dietary control must keep the phenylalanine levels between 2 and 5 mg/dL (120 and 300 micromol/L) until 10 y of age. Thereafter, a progressive and controlled relaxation of the diet is allowed, keeping levels below 15 mg/dL until the end of adolescence and below 20 mg/dL (1200 micromol/L) in adulthood. A lifelong follow-up is recommended for PKU women to prevent for maternal PKU.
Topics: Child; Child, Preschool; Diet Therapy; Humans; Monitoring, Physiologic; Phenylalanine; Phenylketonurias
PubMed: 17513425
DOI: 10.1093/jn/137.6.1561S -
Journal of Zhejiang University.... Oct 2005A hydroponic experiment carried out to study the effect of five Cd levels on growth and photosynthesis of two tomato cultivars showed that the addition of 0.1 micromol/L...
A hydroponic experiment carried out to study the effect of five Cd levels on growth and photosynthesis of two tomato cultivars showed that the addition of 0.1 micromol/L Cd induced a slight increase in plant height of Hezuo 903 and the SPAD (the Soil-Plant Analyses Development) value of the 2 cultivars. However, at higher Cd levels, i.e., 1 and 10 micromol/L, root length and volume, plant height, and SPAD value were all significantly reduced. On an average of the 2 cultivars, exposure to 1 and 10 micromol/L Cd for 33 d reduced plant height by 18.9% and 46.4% and SPAD value by 11.2% and 31.6%, compared with control, respectively. Similarly, root length was reduced by 41.1% and 25.8% and root volume by 45.2% and 63.7%, respectively. The addition of Cd in the growth medium also had significant deleterious effect on net photosynthetic rate (Pn) and intracellular CO(2) concentration (Ci), with Pn being reduced by 27.2% and 62.1% at 1 micromol/L and 10 micromol/L Cd treatments compared to the control, respectively, while Ci increased correspondingly by 28.4% and 39.3%.
Topics: Cadmium; Solanum lycopersicum; Photosynthesis; Plant Leaves; Plant Roots; Seedlings
PubMed: 16187410
DOI: 10.1631/jzus.2005.B0974 -
Archives of Disease in Childhood. Fetal... Nov 2007To measure the zinc, copper, selenium and manganese blood levels in a cohort of 68 preterm infants, and to establish any associations with growth and/or dietary intake.
OBJECTIVE
To measure the zinc, copper, selenium and manganese blood levels in a cohort of 68 preterm infants, and to establish any associations with growth and/or dietary intake.
DESIGN
Blood samples were collected at an infant's expected date of delivery (term) and 6 months later. Serum zinc, plasma copper and whole blood manganese were analysed by atomic absorption spectrometry, plasma and red cell selenium were determined by mass spectrometry. Growth and dietary intake determinations have been previously published.
SETTING
Hampshire, England.
RESULTS
Mean (SD) birth weight of the infants was 1.47 (0.434) kg and mean gestation was 31.4 (2.9) weeks. Mean blood levels at term and 6 months were: serum zinc 12.0 (2.6) micromol/l and 13.8 (2.5) micromol/l; plasma copper 10.1 (2.6) micromol/l and 19.2 (3.6) micromol/l; plasma selenium 0.49 (0.15) micromol/l and 0.72 (0.14) micromol/l; red blood cell selenium 1.68 (0.40) micromol/l and 1.33 (0.19) micromol/l; and blood manganese 320 (189) nmol/l and 211 (68) nmol/l, respectively. There were no significant associations between levels of zinc and copper and dietary intakes of those nutrients at either age (dietary intakes of selenium and manganese were not determined). Only copper levels at term were significantly associated (r = 0.31; p = 0.05) with a growth parameter (head circumference).
CONCLUSION
These results provide new information about trace element status in this vulnerable population.
Topics: Child Development; Copper; Diet; Female; Humans; Infant Nutritional Physiological Phenomena; Infant, Newborn; Infant, Premature; Longitudinal Studies; Male; Manganese; Selenium; Trace Elements; United Kingdom; Zinc
PubMed: 17468128
DOI: 10.1136/adc.2006.107755