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B Emmanuel

Publications and source records attributed to B Emmanuel.

At least 19 recordsLinked to original sources
PubMed1998

Fluorescence in situ hybridization for the detection and monitoring of the Ph-positive clone in chronic myelogenous leukemia: comparison with metaphase banding analysis.

In order to analyze the efficiency of interphase FISH for the detection and monitoring of Ph+ cells in chronic myelogenous leukemia (CML) under interferon (IFN) treatment, the following experiments were performed: (1) 98 specimens derived from 32 patients were analyzed in parallel by dual-color FISH and by conventional chromosome analysis (CCA). A 300/200 kb BCR/ABL probe was used in all tests and a smaller 35.5/39 kb probe was tested in parallel in 22 BM samples; (2) 30 BM samples were prepared by direct harvest and by 24-h culture and were analyzed in parallel; (3) PB and BM samples obtained simultaneously from 11 patients were analyzed. The cut-off point for the recognition of BCR/ABL fusion was set at 2.4%, calculated as the mean percent of false positivity in 11 controls plus 3 s.d. A very close correlation was observed (r=0.994, r2=0.988, P < 0.0001) between the percentages of Ph+ cells as assessed by CCA and by interphase FISH in 98 samples (26 at diagnosis). There was a moderate overestimation of the frequency of Ph+ cells by FISH with respect to CCA, that was more evident at low-to-medium values of Ph positivity. Seven specimens without Ph+ metaphases (17-50 cells analyzed) were shown to carry 2.5-8% interphase cells with BCR/ABL fusion. Similar percentages of BCR/ABL+ nuclei were recorded in 22 samples hybridized using the 300/200 kb and the 35.5/39 kb probe-sets (variation range: 0-5%, mean 2.3%). A very good correlation between the frequency of Ph+ interphase cells was observed when analyzing in parallel BM preparations after direct harvest and after 24-h culture. Underestimation of the percentage of BCR/ABL+ cells was noted to occur in 2/11 PB samples, compared to BM samples, the remaining nine cases showing superimposable results at either sites. We arrived at the following conclusions: (1) dual-color FISH enables an accurate detection and monitoring of the size of the Ph-positive clone in CML at diagnosis and after IFN-therapy; (2) FISH is more accurate than CCA, especially at low levels of Ph-positive cells; (3) testing of directly harvested BM samples is feasible and accurate, giving the opportunity to perform centralized FISH analysis in the context of multicentre trials; (4) the percentage of BCR/ABL+ PB cells usually, though not invariably, reflects the frequency of mutated cells in the BM.

Adult↗
PubMed1985

Ketogenic regulation by certain metabolites in rumen epithelium.

In experiments with rumen epithelium incubated in vitro in the presence of butyrate, the ketogenic effect of glucose was shared by epimeric monosaccharides but not by non-metabolizable analogues. 14C from glucose was not incorporated into ketone bodies. Malate increased ketogenesis from butyrate and decreased its oxidation, pyruvate and NH4+ had the opposite effect, and malonate inhibited both processes. The ketogenic effect of glucose was also effective with isovalerate maintaining the high proportion of acetoacetate which is characteristic of this substrate. Rumen epithelium transformed added acetoacetate into 3-hydroxybutyrate. It is concluded that reducing equivalents produced from glucose and other metabolizable substrates are responsible regulators of ketogenesis from butyrate. The results are discussed in view of the functional role of ruminal ketogenesis.

3-Hydroxybutyric Acid↗
PubMed1985

Measures of de novo synthesis of milk components from propionate in lactating goats.

Possible direct contributions of propionate to de novo synthesis of milk components by the mammary gland of lactating goats fed a concentrate-roughage diet have been studied in vivo by primed constant infusion of [1-carbon-14]propionate into the right mammary artery. Specific radioactivities of milk galactose, fatty acids, and protein were higher in the infused than in the uninfused half of the mammary gland, suggesting de novo synthesis of these compounds in the udder. Specific radioactivities of milk glucose in both udder halves were identical, ruling out any possibility of mammary gland-derived glucose from propionate of blood plasma under the experimental conditions. Of milk galactose, .8% was derived from propionate of blood plasma, and of milk glucose, 98% was derived from glucose of blood plasma. After intraruminal infusion of unlabeled propionic acid at 11 g/h, concentration of propionate in blood plasma was doubled, its contribution to milk galactose was increased to 1.5%, and proportions of milk odd-numbered fatty acids were increased. Propionate was incorporated largely into milk odd-numbered fatty acids (9:0, 11:0, 13:0, 15:0, 17:0). We conclude that small amounts of propionate can be incorporated into principal components of milk in the mammary gland of lactating goats.

Animals↗
PubMed1985

Effects of propionate and methylmalonate on conversions of acetate, butyrate, and D(-)-3-hydroxybutyrate to fatty acids and carbon dioxide by mammary tissue slices of goats.

Incorporations of [1-carbon-14] acetate, [1-carbon-14] propionate, n-[1-carbon-14] butyrate, and D(-)-3-hydroxy[3-carbon-14] butyrate into individual milk fatty acids and their conversion to carbon dioxide were studied in vitro with caprine mammary tissue slices in the presence and absence of propionate and methylmalonate. Neither propionate nor methylmalonate affected incorporation of these substances into fatty acids. In a decreasing order butyrate, acetate, propionate, and D(-)-3-hydroxybutyrate were converted to carbon dioxide. Acetate had the highest incorporation rate into fatty acids followed by D(-)-3-hydroxybutyrate, butyrate, and propionate. Labeled propionate was incorporated mainly into odd-numbered fatty acids. Results do not support the theory that either propionate or its metabolite, methylmalonate, inhibit de novo synthesis of fatty acids in the mammary gland in relation to the etiology of low milk fat syndrome.

3-Hydroxybutyric Acid↗
PubMed1984

Cholesterogenesis from propionate: facts and speculations.

Cholesterogenesis from [1-14C]acetate and [2-14C]propionate by the liver and adipose tissue has been studied in vitro. In all species tested including the rat, mouse, chicken, cow and pig, labelled propionate was recovered in cholesterol following the same trend as acetate, but at lower incorporation rates. Chicken liver was the most active in incorporating both substrates into cholesterol. In the cow and pig, the rates of cholesterol synthesis were higher in the adipose tissue than in the liver. Three alternative mechanisms are proposed to explain the recovery of propionate in cholesterol.

Acetates↗
PubMed1984

The ketogenic effect of glucose in rumen epithelium of ovine (Ovis aries) and bovine (Bos taurus) origin.

In experiments with rumen epithelium incubated in vitro the ratio of 3-hydroxybutyrate: acetoacetate produced was similar to the ratio reported for portal blood, and the ratio ketogenesis: oxidized to CO2 of butyrate was also close to values reported in vivo. Ovine and bovine epithelium incubated with butyrate differed significantly by the values of about 12-17 and 4-7 obtained for the ratio of 3-hydroxybutyrate: acetoacetate. Increasing levels of butyrate in the incubation medium resulted in a decreasing proportion of butyrate oxidized to CO2 and an increasing proportion of ketogenesis. The addition of glucose to butyrate in the incubation medium significantly increased the rate of ketogenesis from butyrate by ovine and bovine tissues. The addition of glucose to butyrate in the incubation medium significantly decreased the rate of butyrate oxidation to CO2 by ovine and bovine tissues. The ketogenic effect of glucose was also apparent in perfused rumen epithelium with butyrate at the mucosal side and glucose at the serosal side.

3-Hydroxybutyric Acid↗
PubMed1984

Effect of propionic acid on ketogenesis in lactating sheep fed restricted rations or deprived of food.

Propionic acid was used as a possible preventive agent against ketogenesis. A total of 12 Suffolk lactating sheep were allocated to groups of 4 and fed isocaloric isonitrogenous rations containing 0, 5 and 10% propionic acid for 2 wk at 1.25 kg twice daily, followed by 4 days of food restriction to .5 kg/day and 2 days of food deprivation to induce ketogenesis. During the restricted feeding, concentrations of glucose in blood plasma were higher (50 to 57 versus 41 to 53 mg/dl) and concentrations of D (--)-3-hydroxybutyrate and acetoacetate lower (3.0 to 5.9 versus 3.9 to 7.6 mg/dl; .39 to .83 versus .43 to .92 mg/dl) in animals fed propionic acid. Propionic acid did not change free fatty acid concentrations of blood plasma or milk and subcutaneous fatty acid composition. Restricted feeding and fasting markedly lowered glucose and elevated concentrations of ketone bodies and free fatty acids in plasma. Furthermore, during these periods proportions of milk fatty acids containing 4 to 14 carbon atoms were decreased and those of stearic and oleic acid (18:0 and 18:1) were increased (16.6 versus 6.5%; and 41.0 versus 17.4%).

3-Hydroxybutyric Acid↗
PubMed1984

Effect of propionic acid on kinetics of acetate and oleate and on plasma and milk fatty acid composition of goats.

Entry rates of acetate and oleate and their incorporation into lipids of blood plasma and fatty acids of milk were studied in lactating goats fed a concentrate-roughage ration with propionic acid infused intraruminally at 0, 5.52, and 13.74 g/h by primed constant intravenous infusion of [1-carbon-14] acetate and [9, 10-hydrogen-3] oleate. Means for infusion rates were acetate, 60, 52, and 39 micrograms/ml blood plasma; propionate 9, 12, and 22 micrograms/ml; oleate, 19, 14, and 12 micrograms/ml; acetate entry rate, 3.9, 2.7, and 1.8 mmol/h per kg bodyweight; oleate entry rate, 47, 29, and 19 mumol/h per kg bodyweight; acetate oxidation rate, 2.0, 1.7, and 1.4 mmol/h per kg, and its contribution to the total carbon dioxide production, 16, 14, and 11%. Propionic acid increased incorporation of carbon-14 and hydrogen-3 into plasma lipids, elevated proportions of 7:0, 9:0, 11:0, 13:0, 15:0, and 17:0 fatty acids in milk, and tended to lower others. Specific radioactivities of milk fatty acids during infusion of propionic acid were elevated by 1.8 to 2.8 times, and total fatty acids in milk and plasma were lowered by 22 and 38%. Data support the glucogenic theory that propionic acid either directly or through gluconeogenesis stimulates insulin secretion, which in turn inhibits release of fatty acids from adipose tissue, resulting in milk fat depression.

Acetates↗
PubMed1984

Kinetics of methionine and choline and their incorporation into plasma lipids and milk components in lactating goats.

Rates of entry of L-methionine and choline and their incorporations into lipids of blood plasma and milk components were studied in lactating goats fed a concentrate-roughage ration with primed constant infusion of L-[methyl-carbon-14] methionine and [methyl-carbon-14] choline. Entry rates of methionine and choline were 30 and 47 mumol/h/kg body weight. Of the methionine pool, 10 and 28% were recovered in carbon dioxide and choline of blood plasma, but the contribution of methionine to the total carbon dioxide production was negligible. Two percent of serine was derived from methionine. Six percent of the choline pool was derived from methionine, whereas labeled choline was not recovered in methionine. Methionine and choline contributed to at least 4 and 19% of the phospholipid pool. Of the methionine dose, .2 and 3.7% appeared in milk lactose and protein. Little (.3%) labeled choline was recovered in milk; however, its contribution to milk fat was 10 times as high as that of methionine. The lipogenic effect of methionine in the liver is proposed as one mechanism among others stimulating production of milk and milk fat.

Animals↗
PubMed1983

Simultaneous determination of total cholesterol concentration and radioactivity in plasma.

Total plasma cholesterol concentration and radioactivity were measured simultaneously using a gas chromatograph equipped with a flame ionization detector and an effluent splitter. More than 99% of the recovered radioactivity was in the cholesterol peak. Specific activities were highly correlated with the amounts of labeled cholesterol present in plasma. The recovery of label was quantitative over a wide range of carrier cholesterol concentrations. The method is highly reproducible, accurate, rapid and specific.

Acetates↗
PubMed1983

Rates of entry of alanine and glycerol and their contribution to glucose synthesis in fasted chickens.

Rates of entry of alanine and glycerol and their contribution to glucose synthesis were studied in 48-h fasted White Leghorn cockerels using primed constant intravenous infusions of L-[U-14C]alanine and [U-14C]glycerol. Entry rates of alanine and glycerol were 112 and 401 mumol/h per kg body weight, respectively. Of the total glucose irreversible loss (entry rate), 1.5 and 6.6% were derived from alanine and glycerol, respectively. The possibilities of the operation of a glyoxylate cycle and omega-oxidation of fatty acids in the fasted chicken are discussed.

Alanine↗
PubMed1982

Rates of entry and oxidation of D(-)-3-hydroxybutyrate and glucose in fed and fasted chickens.

Rates of entry and oxidation of D(-)-3-hydroxybutyrate (DBHB) and glucose and their contribution to the total metabolic production of CO2 were studied in fed and 48-hr fasted Leghorn roosters using primed constant intravenous infusions of NaH14CO3, D(-)-3-[3-14C]-hydroxybutyrate, and D-[U-14C] glucose. Fasting increased plasma DBHB concentrations sixfold but did not change plasma glucose levels. In both states of nutrition, rates of CO2 production were identical (P greater than .05). Mean fractions of the total CO2 derived from DBHB and glucose in fed and fasted chickens, respectively, were: DBHB, 1.7 and 9.9% (P less than .001); glucose, 29 and 10% (P less than .001). Entry rates of DBHB and glucose in fed chickens were 276 and 5936 mumoles/hr per kg (P less than .001), respectively, and in starved birds were 1703 and 2204 mumoles/hr per kg (P less than .001), respectively. Fasting increased the oxidation rate of DBHB from 124 to 737 mumoles/hr per kg (P less than .001) and decreased the oxidation rate of glucose from 1491 to 525 mumoles/hr per kg (P less than .001). During fasting, glucose homeostasis is maintained in part by concomitant decreases in glucose entry and oxidation rates. The results are discussed with reference to the sparing effect of DBHB on glucose oxidation.

3-Hydroxybutyric Acid↗
PubMed1979

A comparative study of ketone body metabolism between the camel (Camelus dromedarius) and the sheep (Ovis aries).

1. Plasma levels of beta-hydroxybutyrate (BHB), and acetoacetate (AcAc) have been measured in camels (Camelus dromedarius) and sheep (Ovis aries). The activity of beta-hydroxybutyrate dehydrogenase (BHB-deH2) (E.C. 1.1.1.30) was studied in the rumen epithelium and the liver of these animals. 2. Concentrations of plasma BHB and AcAc in the camel were in respective order 33 and 4 times lower than that of the sheep. The ratios of BHB to AcAc were 0.61 and 4.8 for the camel and sheep, respectively. 3. The activity of BHB-deH2 in the rumen epithelium of the camel and sheep were 7.15 and 66 mumol/hr/g wet wt tissue, respectively. The activity in both species was higher in the rumen epithelium than in the liver.

Acetoacetates↗
PubMed1979

Specific methods for the determination of radioactivity in D-(-)-3-hydroxybutyrate in blood plasma.

Two simple, high-yield rapid methods with good reproducibility are described, which permit the determination of radioactivity in plasma D-(-)-3-hydroxybutyrate. The compound is converted to acetoacetate, using a modified enzymatic method. In procedure 1, acetoacetate is reacted with 2,4-dinitrophenylhydrazine; the resulting hydrazone is oxidised by means of a sample oxidiser, and the product 14CO2 is collected in scintillation liquid and counted. In procedure 2, a Conway microdiffusion unit is applied. The acetoacetate is decarboxylated to acetone in the presence of o-phenylenediamine, and the acetone is then diffused into semicarbazide solution. This solution, containing the semicarbazone derivative of labelled acetone, is transferred to liquid scintillation and counted. In both procedures the radioactivity is measured simultaneously in a separate sample which was not subjected to the enzymatic conversion of D-(-)-3-hydroxybutyrate. The difference in radioactivity between the two samples is attributed to labelled (D-(-)-3-hydroxybutyrate.

Carbon Radioisotopes↗