Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “MONOSACCHARIDES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,657 records · Page 92Linked to original sources
PubMed1994

Studies on the constituents of Solidago virga-aurea L. III. Structures of solidagosaponins XXI-XXIX.

From the most polar fractions of Solidago virga-aurea L. (Compositae), 9 oleanane-type triterpene saponins named solidagosaponins XXI-XXIX (1-9) were isolated, together with a known saponin, virgaureasaponin 2 (10). These saponins are bisdesmosidic glycosides having two monosaccharides at C-3 and four or five monosaccharides at C-28. Their structures were established on the basis of spectroscopic and chemical evidence.

Carbohydrate Sequence↗
PubMed2006

Physical characteristics of freeze-dried griseofulvin-lipids nanoparticles.

We have attempted to prepare micronized drug particles and to maintain the micronized state long-term in order to improve the solubility of a practically insoluble drug, griseofulvin (GF). GF nanoparticles (GFNPs) prepared by high-pressure homogenization were micronized to about 45 nm (mean particle size). GFNPs were subjected to transmission electron microscopy (TEM) observation. The mean particle size remained at about 50 nm for 3 months at 25 degrees C. However, increased to about 300 nm in 6 months. After 5% (w/v) sugar was added, GFNP was freeze-dried and rehydrated. The mean particle size of the rehydrated GFNPs was about 160 nm when the sugar was a monosaccharide. In contrast, it was about 55-65 nm when the sugar was a disaccharide. The powder X-ray diffraction pattern of the monosaccharide-containing freeze-dried GFNPs revealed a crystal state of sugar. On the other hand, that of the disaccharide-containing freeze-dried GFNPs indicated an amorphous state of sugar. From this result, it is considered that the high viscosity of an amorphous sugar prevents GFNPs from aggregating through retardation of molecular movement. Freeze-dried GFNPs stored for six months at 25 degrees C showed a good re-dispersibility. After the rehydration the mean particle size of GFNPs was 55-65 nm. It was found that freeze-dried GFNPs containing sucrose, maltose or trehalose were stable for longer periods than GFNP suspensions.

Antifungal Agents↗
PubMed1995

Gas chromatography-mass spectrometric studies of canine urinary metabolism.

After the urine was treated with urease, lyophilized, and trimethylsilylated, it was examined for metabolic profiles in Dalmatian dogs and Shetland sheepdogs by gas chromatography-mass spectrometry (GC/MS), which simultaneously analyzes organic acids, amino acids, sugars, sugar alcohols, purine and pyrimidine bases, and nucleosides. The profiles were compared with those from human specimens. As clarified in past studies, Dalmatian dogs showed an extreme decrease in allantoin, which is the final product of purine metabolism in the canine of other species, and a marked detection of uric acid peak. This finding suggests that purine metabolism in Dalmatian dogs is different from that in the other species. Only two Shetland sheepdogs, whose mother had chronic renal failure, showed a marked excretion of uric acid, as in Dalmatian dogs. In addition, some Dalmatian dogs, who were maintained on a protein-restricted diet, showed a little excretion of uric acid. A large amount of uric acid is detected in combination with pentose-monosaccharides, hexose-monosaccharides and sugar alcohols in neonatal human urine in comparison with the present dog samples. A marked difference between the canine and the humans is that phenylacetylglycine, which is derived from the aromatic amino acid phenylalanine, is excreted in the canine urine. Phenylacetylglycine is not detected in the human urine, and there have been no reports of its excretion in canine urine.

Amino Acids↗
PubMed2004

Comparison of two posthydrolysis processes of Brewery's spent grain autohydrolysis liquor to produce a pentose-containing culture medium.

A readily fermentable pentose-containing hydrolysate was obtained from Brewery's spent grain by a two-step process consisting of an auto-hydrolysis (converting the hemicelluloses into oligosaccharides) followed by an enzymatic or sulfuric acid-catalyzed posthydrolysis (converting the oligosaccharides into monosaccharides). Enzymatic hydrolyses were performed with several commercial enzymes with xylanolytic and cellulolytic activities. Acid-catalyzed hydrolyses were carried out at 121 degrees C under various sulfuric acid concentrations and reaction times, and the effects of treatments were interpreted by means of a corrected combined severity factor (CS*), which varied in the range of 0.80-2.01. Under the tested conditions, chemical hydrolysis allowed higher pentose yields than enzymatic hydrolysis. Optimized conditions (defined by CS* = 1.10) allowed both complete monosaccharide recovery and low content of inhibitors. Liquors subjected to posthydrolysis under optimal conditions were easily fermented by Debaryomyces hansenii CCMI 941 in semiaerobic shake-flask experiments, leading to xylitol and arabitol as major fermentation products. The bioconversion process was improved by hydrolysate concentration and supplementation of fermentation media with casamino acids.

Alcoholic Beverages↗
PubMed1981

Decreased carbohydrate content of rat plasma apolipoproteins in galactosamine hepatitis.

The total carbohydrate content and the monosaccharide composition of plasma apolipoproteins isolated from normal and D-galactosamine-treated rats were investigated. In the lipoprotein classes VLDL, LDL and HDL of control animals, the carbohydrate content was 5,5%, 3,4% and 2,9% of dry weight apolipoprotein, respectively. 24 h after galactosamine treatment, these values dropped to 1.8%, 1.6% and 2.3%. The reduction of the carbohydrate content in VLDL and LDL was mainly due to a decrease of the following monosaccharides: Mannose, galactose, N-acetylglucosamine and sialic acid. Minor changes were observed in the fucose, glucose and N-acetylgalactosamine content. Particularly, the mannose/galactose ratio in the LDL fraction fell from 2.3 in control animals to 1.0 in the galactosamine-treated animals. In another series of experiments, the time course of these carbohydrate alterations in the LDL apolipoprotein was studied. As early as 3 h after galactosamine application, we found a reduction of the mannose, galactose and N-acetylglucosamine levels, with the absolute minimum at 24 h, and later on a normalization at 48 and 72 h.

Acetylglucosamine↗
PubMed1984

The sugar spectrum of human cholesterol gallstones, mixed and pigment gallstones: combined quantitative analysis of neutral sugars, N-acetylhexosamines, hexuronic and N-acetylneuraminic acids by capillary gas-liquid chromatography.

Glycoproteins were investigated in different types of biliary calculi by a methanolysis procedure of the carbohydrate moiety, the formation of 2,6-dinitro-4-trifluoromethylbenzenesulphonate derivatives of N-acetylhexosamines and N-acetylneuraminic acid, followed by separation, identification and quantification of the liberated monosaccharides using capillary gas-liquid chromatography. This indirect method avoids several analytical problems caused by the presence of bile pigment derivatives; unless these are carefully removed they interfere strongly in the measurement of protein. The carbohydrate contents were much higher in pigment stones than in cholesterol and mixed stones. Rhamnose, a non-mammalian monosaccharide, was identified in most samples, but was significant increased in pigment stones, indicating a bacterial history of this stone type.

Carbohydrates↗
PubMed1997

Proteolytic release and partial characterization of human sperm-surface glycopeptides.

Sperm-surface glycopeptides were obtained from intact sperm membranes after proteolytic release by different enzymatic treatments such as autoproteolysis, trypsin, papain and pronase. Glycopeptides were isolated, their properties and composition were examined, and their monosaccharide and amino acid constituents were characterized. The monosaccharides identified were fucose, mannose, galactose, N-acetylglucosamine, and N-acetylgalactosamine, which form part of more than one type of oligosaccharide units. Autoproteolytic treatment mainly provided O-glycosidic type oligosaccharides, while a mixture of O- and N-glycosidic oligosaccharides was obtained in variable proportions when treated with trypsin, papain or pronase. The highest degree of peptide cleavage was obtained with pronase. Despite the higher yields reached with trypsin, these glycopeptides contain the lowest percentage of oligosaccharide chains. Proteolytic treatment provides a simple, rapid procedure for the isolation of glycopeptides from the sperm surface.

Glycopeptides↗
PubMed2006

Apoptosis and adhesion of hemocytes during molting stage of silkworm, Bombyx mori.

To clarify the regulatory mechanism of the rapid changes in the hemocyte density in the silkworm, Bombyx mori, during ecdysis, we evaluated the relationship between the hemocyte density and the incidence of apoptosis during this stage. We also evaluated the role of the sugar chains on the adhesion of hemocytes by analyzing the effects on the hemocyte density of the injection of enzymes that cut sugar chains and monosaccharides into the body cavity. The hemocyte density was increased in the molting stage and spinning, and then decreased after the ecdysis. During spinning, the diameter of the granulocytes markedly increased, in which fatty granules in the cytoplasm increased, becoming foamy. They were identified to be apoptotic hemocytes using the Hoechst staining and the Comet assay. The decrease in the hemocyte density during spinning was mainly caused by the apoptosis of granulocytes. Next, we focused on the fluctuation of hemocyte density during the molting stage. Examination of the changes in the hemocyte density induced by injecting glycoside hydrolases, neuraminidase, sialic acid, or monosaccharides into the body cavity during the fourth molt stage and the third day in fifth instar larva demonstrated that the alteration of hemocyte density was regulated by the attachment and detachment of hemocytes via a selectin ligand, sugar chains. As with the injection of glycoside hydrolase, neuraminidase, sialic acid and fucose raised the hemocyte detachment, and it was assumed that the selectin ligands include the sialyl Lewis x like sugar chains, the same as mammalian lymphocytes.

Animals↗
PubMed1994

A risk-benefit appraisal of acarbose in the management of non-insulin-dependent diabetes mellitus.

Acarbose is an alpha-glucosidase inhibitor proposed for the treatment of diabetic patients. It acts by competitively inhibiting the alpha-glucosidases in the intestinal brush border. The principal action of these enzymes is to convert nonabsorbable dietary starch and sucrose into absorbable monosaccharides (e.g. glucose). Enzyme inhibitors delay this conversion, slowing the formation and consequently the absorption of monosaccharides, and thus reducing the concentration of postprandial blood glucose. Both starch and sucrose are influenced, whereas lactose and glucose are not. Many studies in experimental animals, healthy volunteers and patients with non-insulin-dependent diabetes mellitus (NIDDM) have shown that acarbose decreases postprandial blood glucose, with a lesser reduction of fasting blood glucose, plasma triglycerides and postprandial insulin levels. In long term studies in NIDDM patients, acarbose significantly reduced glycosylated haemoglobin levels. Acarbose is only minimally absorbed from the gut and no systemic adverse effects have been demonstrated after long term administration. The drug allows undigested carbohydrates to pass into the large bowel where they are fermented causing flatulence, bloating and diarrhoea. These symptoms, which occur in approximately 30 to 60% of patients, tend to decrease with time and seem to be dose-dependent. They are minimised by starting therapy with low doses (such as 50mg 3 times daily) which may be effective in many patients. An increase in serum hepatic transaminases observed in earlier studies in the US, where doses of acarbose up to 900mg daily were used, has been not reported with the lower doses of the drug actually recommended [150 to 300mg (up to 600mg) daily]. In conclusion, acarbose may be useful in patients with NIDDM when diet alone is no longer able to maintain satisfactory blood glucose control. Furthermore, it may be a valid alternative to sulphonylurea or biguanide therapy when these drugs are contraindicated and insulin administration may be delayed. Acarbose seems also to be a useful adjunct to hypoglycaemic oral agents but its precise role in this field has not been fully clarified.

Acarbose↗
PubMed1988

Fluorescent probe studies of sodium/sugar cotransport and membrane potential changes in isolated chicken enterocytes.

The fluoroprobe technique using a potential-sensitive dye, diS-C3(5), was applied to isolated enterocytes in order to correlate membrane potential changes with Na+/sugar cotransport. Cells were prepared from the chicken small intestine by enzymatic (Dispase) treatment combined with mechanical agitation. In the presence of Na+, addition of D-glucose (2 mM) to the suspension of cells doped with the dye (1.8 microM) gave rise to Na+-dependent increases in fluorescence indicative of depolarization of the cell membrane potential. The pH optimum for this response was ca. 7.3. Similar but smaller fluorescence increases were also evoked by D-galactose, alpha-methyl-D-glucoside, and 3-O-methyl-D-glucose, all known to be actively accumulated by enterocytes in a Na+-dependent fashion. These monosaccharide-evoked fluorescence changes were suppressed by lowering the extracellular Na+ concentration or by phlorizin. Monosaccharides with no reported Na+ requirement induced no such fluorescence responses. A disaccharide, maltose, elicited a smaller fluorescence increase which also was Na+ dependent and phlorizin inhibitable; this was interpreted as due to a possible supply of D-glucose by the membrane-bound disaccharidase systems. No change was observed with lactose, sucrose, or trehalose, however. The glucose-evoked fluorescence changes correlatable with depolarization were also confirmed using another carbocyanine, diO-C5(3). These results demonstrate that fluorescence from diS-C3(5) or diO-C5(3) can be a good measure for cotransport-associated membrane potential changes in isolated intestinal epithelial cells.

Animals↗
PubMed1991

Trans-hydroxyl group configuration on carbons 2 and 3 of glucose. Responsible for acute inhibition of myo-inositol transport?

Cultured neuroblastoma, cerebral microvessel endothelial, and retinoblastoma cells were used to examine the mechanism of acute inhibition by D-glucose of myo-inositol uptake. Acute exposure of the cells to 30 mM D-glucose caused a significant decrease in Na(+)-dependent myo-inositol uptake in all three cell types. The effect of D-glucose to acutely inhibit myo-inositol uptake was dependent on the extracellular glucose concentration and was not reversed by sorbinil. 2-Deoxy-D-glucose (30 mM), 3-O-methyl-D-glucose (30 mM), and cytochalasin B (100 microM) did not acutely inhibit myo-inositol uptake. These data suggest that the hydroxyl groups on carbons 2 and 3 of D-glucose, which in a Haworth projection appear trans to each other, are important for inhibitory activity. Other monosaccharides (30 mM) having a similar 2,3-trans-diol configuration, L-glucose, D- and L-fucose, D- and L-galactose, D- and L-xylose, and D-arabinose, all to varying degrees significantly inhibited myo-inositol uptake. In all cases, the L-isomers were more potent inhibitors of myo-inositol uptake than the corresponding D-isomers. Monosaccharides (30 mM) having hydroxyl groups on carbons 2 and 3 in a cis configuration, D-mannose, L-rhamnose, D-allose, and D-ribose, did not acutely inhibit myo-inositol uptake. Replacing the hydroxyl group with a fluorine on carbons 2 or 3 of D-glucose negated its inhibitory activity of myo-inositol uptake. In contrast, replacing the hydroxyl group with a fluorine on carbon 6 of D-glucose did not block its inhibition of myo-inositol uptake.(ABSTRACT TRUNCATED AT 250 WORDS)

3-O-Methylglucose↗
PubMed1992

Effect of alkaline hydrogen peroxide treatment on cell wall composition and digestion kinetics of sugarcane residues and wheat straw.

Our objective was to characterize changes in cell wall composition and digestibility of sugarcane bagasse, pith from bagasse, and wheat straw after treatment with alkaline hydrogen peroxide (AHP). The AHP treatment solution contained 1% H2O2 (wt/vol) maintained at pH 11.5 with NaOH. The H2O2 in solution amounted to 25% of the quantity of substrate treated. After treatment, residues were washed and dried. Detergent fiber composition, total fiber components (neutral sugars, uronic acids, Klason lignin, and noncore lignin phenolic acids), IVDMD, in vitro digestion kinetics of NDF, and monosaccharide digestibilities (24 and 120 h) were determined. Total fiber (TF) and NDF concentrations of all treatment residues were increased (P less than .05) over control substrates by AHP because of greater losses of cell solubles than of cell wall constituents. Hemicellulose:cellulose ratio in NDF of treatment residues was decreased (P less than .05) by AHP for all substrates, but the neutral sugar composition of TF did not agree with this preferential loss of hemicellulose components. Klason lignin, ADL, and esterified noncore lignin, especially ferulic acid, were reduced (P less than .05) by AHP, whereas etherified noncore lignin composition was unchanged. Treatment increased (P less than .05) IVDMD, extent of NDF digestion, and monosaccharide digestibilities of all crop residues. The rate of NDF digestion was increased (P less than .05) for the sugarcane residues but not for wheat straw. Alkaline hydrogen peroxide improved crop residue digestibility, probably as a result of the removal of core and noncore lignin fractions.

Animal Feed↗
PubMed1994

Ruminal digestion and glycosyl linkage patterns of cell wall components from leaf and stem fractions of alfalfa, orchardgrass, and wheat straw.

Samples of alfalfa, orchardgrass, and wheat straw were hand-separated into leaf and stem fractions that were subjected to in situ ruminal fermentation for various lengths of time to assess the rate and extent of degradation of cell wall neutral monosaccharides, uronic acids, acetyl groups, and hydroxycinnamic acids. A second objective was to measure the glycosyl linkage patterns of leaf and stem fractions of substrates before and after ruminal fermentation. Samples were fermented for 0, 6, 12, 24, 48, 96, and 192 h in each of two ruminally cannulated steers. In situ disappearance data were fitted to a first-order exponential equation to estimate the following substrate parameters: insoluble, potentially digestible fraction (fd), indigestible fraction (fi), and fractional rate constant of degradation of the potentially digestible fraction (k). Leaves contained larger concentrations of crude protein and smaller concentrations of cell wall components than did stem fractions. Estimates of fi were 7.3, 39.2, 22.1, 49.3, 27.7, and 36.3 for dry matter disappearances for alfalfa leaf, alfalfa stem, orchardgrass leaf, orchardgrass stem, wheat straw leaf, and wheat straw stem, respectively. Averaged across substrates, estimates of fi for arabinose, galactose, glucose, xylose, uronic acids, acetyl groups, and p-coumaric acid were 16.5, 11.4, 14.8, 31.2, 12.8, 25.3, and 22.6% in leaf fractions and 29.5, 19.9, 37.5, 56.2, 35.0, 52.4, and 44.6% in stem fractions. Rates of digestion of all monomeric components except galactose and xylose were greater (P < .05) for alfalfa than for orchardgrass or wheat straw. Differences in digestibility of cell wall components from leaf and stem fractions were greater in alfalfa and orchardgrass than in wheat straw. Glycosyl linkage analysis indicated that xylans in leaf and stem fractions of alfalfa, orchardgrass leaf, and wheat straw stem that resisted degradation had a lower degree of substitution with acid-labile constituents (i.e., other monosaccharides) than was found in original substrates. Different rates and extents of digestion of leaf and stem fractions of forages explain part, but not all, of the observed differences in digestibilities of cell wall monomers by ruminants.

Animals↗
PubMed1999

Effects of different supplemental sugars and starch fed in combination with degradable intake protein on low-quality forage use by beef steers.

Twenty ruminally fistulated steers (Exp. 1, 448 kg and Exp. 2, 450 kg) were used in two consecutive randomized complete block experiments with five treatments in each experiment. The purpose was to evaluate the impact of feeding different supplemental sugars or starch in combination with supplemental degradable intake protein (DIP) on the utilization of low-quality tallgrass-prairie hay. In Exp. 1, steers were given ad libitum access to forage and, except for the negative control (NC), received a limited supply (insufficient to maximize forage use) of supplemental DIP (.031% BW/d, DM basis). In addition to the NC, this experiment included four supplementation treatments in which one of four carbohydrate (CHO) sources (starch, glucose, fructose, or sucrose) was fed at .30% BW of DM/d. In Exp. 2, the treatment structure was identical except that the supplemental DIP level (.122% BW, DM basis) was near the level needed to maximize forage use. Forage OM intake (FOMI) was not affected (P> or =.26) by supplementation in Exp. 1 but was increased (P = .05) in Exp. 2. However, no difference (P> or =.46) in FOMI occurred among CHO sources in either experiment. Total OM and digestible OM intakes were increased (P<.01) by supplementation in both experiments. In Exp. 1, no difference (P>.26) in OM digestion (OMD) occurred among treatments. In Exp. 2, supplementation increased (P<.01) OMD. Additionally, sugars yielded a higher (P = .04) OMD than starch, and the monosaccharides yielded a higher (P = .02) OMD than sucrose. In Exp. 1, NDF digestion (NDFD) was decreased (P = .02) by supplementation, but no differences (P> or =.21) occurred among CHO sources. In Exp. 2, NDFD was increased (P = .03) by supplementation. Additionally, sugars led to higher (P = .05) NDFD than starch, and the monosaccharides led to higher (P = .03) NDFD than sucrose. In both experiments, discernible patterns were observable with regard to the effects of supplementation and type of supplemental CHO on ruminal fermentation characteristics. In conclusion, even though some consistency in fermentation profiles for different carbohydrate sources was evident in both experiments, forage intake and digestion responses were not consistent across experiments. This raises the possibility that carbohydrate source may interact with the amount of supplemental DIP fed and, as such, deserves additional investigation.

Animal Feed↗
PubMed2007

Afternoon harvest increases readily fermentable carbohydrate concentration and voluntary intake of gamagrass and switchgrass baleage by beef steers.

Our objective was to determine if harvest in the morning (AM, 0600) vs. the afternoon (PM, 1800) affects composition and voluntary DMI of gamagrass (GG) or switchgrass (SG) stored as baleage. Iuka GG (Tripsacum dactyloides L.) and Alamo SG (Panicum virgatum L.) were cut with a mower-conditioner, immediately round-baled, wrapped in plastic, and stored as baleage. Beef steers (255 +/- 7 kg of BW) were assigned (5 steers/treatment) to GG/AM, GG/PM, SG/AM, or SG/PM. Ad libitum intake was measured for 21 d (7-d adjustment and 14-d intake estimate) followed by 7-d adjustment and 5-d digestion and N balance study. Chewing behavior was recorded during the balance study. Compared with AM, PM had more (P < 0.01) starch (9.3 vs. 4.7 g/kg of DM), total nonstructural carbohydrate (30.4 vs. 19.0 g/kg of DM), and monosaccharides (17.1 vs. 11.2 g/kg of DM). Compared with AM, PM had less (P = 0.05) acetate (13.0 vs. 18.6 g/kg of DM) and propionate (0.29 vs. 0.82 g/kg of DM) and tended (P < 0.13) to have less lactate (2.9 vs. 3.5 g/kg of DM) and butyrate (3.9 vs. 5.1 g/kg of DM). Compared with SG, GG had more (P = 0.01) DM (324 vs. 242 g/kg of baleage), CP (114 vs. 97 g/kg of DM), lactate (4.8 vs. 1.6 g/kg of DM), starch (9.4 vs. 4.7 g/kg of DM), total nonstructural carbohydrate (34.2 vs. 15.2 g/kg of DM), and monosaccharides (20.8 vs. 7.4 g/kg of DM). However, GG had a lower (P = 0.01) pH (5.32 vs.5.79) and less (P < 0.01) ethanol (18.7 vs. 27.3 g/kg of DM), acetate (12.3 vs. 19.2 g/kg of DM), propionate (0.00 vs. 1.11 g/kg of DM), and butyrate (0.6 vs. 8.4 g/kg of DM). Daily DMI (2.16 vs. 1.83% of BW) and digestible DMI (1.15 vs. 0.95% of BW) were greater (P = 0.03) for PM than AM. Plasma urea N concentrations at the end of the ad libitum intake phase were greater (P = 0.01) for AM (3.91 mM) than for PM (2.31 mM) and greater (P = 0.07) for GG (3.51 mM) than for SG (2.71 mM). Steers fed PM spent more time eating (P = 0.04) and less time resting (P = 0.01) during meals than steers fed AM. Apparent digestibility of DM and fiber components was not affected (P < 0.18) by treatment. Apparent digestibility and retention of N decreased from PM to AM for SG, but increased for GG (P = 0.05). Retention of N as a percentage of N intake or N digested decreased more from PM to AM for SG than for GG (P < 0.05). We conclude that increased nonstructural carbohydrate content of the PM harvest of these grasses stored as baleage caused increased voluntary intake and improved use of dietary N by beef steers.

Agriculture↗
PubMed1996

Lectin binding characteristics of squamous cell carcinomas of the head and neck.

Lectins are polyvalent proteins of non-immune origin with exquisite carbohydrate binding specificity making them ideal for investigation of cell surface glycoprotein and glycolipid antigens. We examined the cell surface lectin binding phenotypes of 20 UM-SCC squamous cell carcinoma cell lines established from 17 patients with head and neck cancers using a panel of fluorescein-conjugated lectins and inhibition by the appropriate monosaccharide to confirm specificity of using a panel of fluorescein-conjugated lectins and inhibition by the appropriate monosaccharide to confirm specificity of binding. Conconavalin A (Con A) from Canavalia ensiformis and the peanut agglutinin (PNA) from Arachis hypogaea bound all SCC cell lines tested and wheat germ agglutinin (WGA) from Triticum vulgaris bound to 12 of 13 tumor cell lines. The blood group O specific lectin UEA 1 from Ulex europeus also bound to all cell lines regardless of the donor blood type. Lectins of Dolichos biflorus (DBA) and Griffonia simplicifolia (GS I-B4 or BSA I-B4) with binding specificity for glycoproteins associated with blood group A and B respectively, had reactivity that did not directly correlate with blood group antigen expression. In contrast to the other lectins in our panel which exhibited broad reactivity with SCC antigens, the BSA-II lectin from Griffonia simplicfolia, (GS II or BSA II) which has sugar binding specificity for terminal non-reducing GlcNAc, did not bind to any of the screened cell lines. Our results demonstrate a common pattern of lectin-defined carbohydrate expression on the cell surface of squamous cell carcinomas of head and neck that appears promising in defining the malignant cellular phenotype. Lectin binding profile may be useful in differentiating benign from malignant histopathology.

Adult↗
PubMed1977

Rates and mechanisms of glucose, galactose, and xylose absorption in man in vivo.

Jejunal absorption-rates of glucose, galactose, and xylose were determined consecutively, using a double-lumen tube perfusion technique, in 6 Arab subjects in vivo; perfusion solutions contained 200 mmol/l of each monosaccharide. Mean xylose absorption rate was significantly lower than that for glucose (P less than 0.001) and galactose (P less than 0.001). In order to investigate evidence that glucose and xylose share the same jejunal transfer mechanism, their absorption-rates when given alone and together, at high concentrations, were determined in 6 other Arabs; perfusion solutions contained (1) 200 mmol/l glucose, (2) 100 mmol/l xylose, and (3) 200 mmol/l glucose + 100 mmol/l xylose. Rates of glucose and xylose absorption were not significantly influenced by the other monosaccharide. This study does not therefore confirm existence of a common transfer mechanism. A significant correlation between absorption rate of glucose and weight of xylose excreted after a 25 g oral load (P less than 0.05) was demonstrated.

Adolescent↗
PubMed1992

Fructose and related food carbohydrates. Sources, intake, absorption, and clinical implications.

It is possible to point out subjects consuming considerable quantities of fructose and sorbitol, and the intake seems to be increasing both from added and natural sources. Studies of the absorption of fructose in animals are inconsistent, and the mechanisms of fructose uptake seem to vary in accordance with the species. In most species fructose absorption takes place by a specific carrier (facilitated transport), but it may be active in the rat. In vitro studies of human intestine are very scarce; there is no evidence of active intestinal fructose transport in the human intestine. By means of hydrogen breath tests, a very low absorption capacity for fructose given as the free monosaccharide has been found in humans. Fructose given as sucrose or in equimolar combinations with glucose is well absorbed, and only fructose in excess of glucose is malabsorbed. On this basis it is hypothesized that two different uptake mechanisms for fructose are present in the human intestine. One of these may be a disaccharidase-related uptake system. Sorbitol ingestion may aggravate malabsorption of fructose given as the monosaccharide; it is not known whether a specific mechanism is involved. In children and adults with functional bowel distress the absorption capacities for fructose may not differ from those of healthy individuals, but malabsorption of fructose and/or sorbitol may be the cause of or aggravate abdominal symptoms. Fructose polymers (fructans) are also subject to increasing nutritional interest. Fructans are not absorbed in the small intestine but are strongly fermented in the large bowel. Fructans may be of potential benefit for large-bowel function and blood glucose regulation.

Breath Tests↗