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PubMed2003

Post-harvest processing methods for reduction of silica and alkali metals in wheat straw.

Silica and alkali metals in wheat straw limit its use for bioenergy and gasification. Slag deposits occur via the eutectic melting of SiO2 with K2O, trapping chlorides at surfaces and causing corrosion. A minimum melting point of 950 degrees C is desirable, corresponding to an SiO2:K2O weight ratio of about 3:1. Mild chemical treatments were used to reduce Si, K, and Cl, while varying temperature, concentration, % solids, and time. Dilute acid was more effective at removing K and Cl, while dilute alkali was more effective for Si. Reduction of minerals in this manner may prove economical for increasing utilization of the straw for combustion or gasification.

Agriculture↗
PubMed1979

Immuno-chemical studies on the alkali-labile carbohydrate chains of human serum glycoproteins.

Human serum glycoproteins can be classified into those containing N-acetyl-D-galactosamine and into those lacking this hexosamine. The N-acetyl-D-galactosamine-containing serum glycoproteins have alkali-labile chains containing this hexosamine linked O-glycosidically to hydroxy amino acids. These alkali-labile chains can be demonstrated in neuraminic acid free serum glycoproteins by gas liquid chromatography and by using precipitating lectins from invertebrates and plants. They are represented by two chains, one containing only N-acetyl-D-galactosamine, the other with D-galactose linked (1--3) beta-glycosidically to this hexosamine forming a disaccharide. Serologically these two chains, which usually occur together on one molecule, can be characterized by their reaction with lectins from Helix pomatia (anti-A like) and from Agaricus bisporus and Arachis hypogaea (anti-TF specificity).

Acetylgalactosamine↗
PubMed1996

The milk-alkali syndrome caused by betelnuts in oyster shell paste.

BACKGROUND: The carcinogenic effect of betelnut chewing leading to oral cancer is well known. Betelnut chewing may also affect the autonomic nervous system. In this report, we present another potential hazard of betelnuts, milk-alkali syndrome. CASE REPORT: Two patients who had chewed a large quantity of betelnuts developed hypercalcemia, metabolic alkalosis, and renal insufficiency. They ingested a large amount of calcium carbonate from a local special paste used for betelnut preparation, the main ingredient of which is ground oyster shell. The symptoms and metabolic abnormalities disappeared promptly after abstinence from betelnut chewing and administration of saline solution. Improvement of renal function was observed in both patients. Analysis of the calcium content of the paste suggested that the patients might have ingested 9 g and 6 g of calcium carbonate per day, respectively. CONCLUSION: This is the first report of milk-alkali syndrome not caused iatrogenically, but by recreational usage of oyster shell preparations of betelnuts.

Areca↗
PubMed1998

Effect of wheat straw treated with alkali on ruminal function and lactational performance of dairy cows.

Two experiments were conducted to evaluate the effects of wheat straw treated with alkali on ruminal function and lactational performance of dairy cows. In Experiment 1, four ruminally fistulated Holsteins cows (X = 57 d of lactation) were fed four diets that contained 0, 20, 30, or 40% (dry basis) wheat straw treated with 3% NaOH plus 3% Ca(OH)2 in a 4 x 4 Latin square. The diets contained 60, 40, 30, and 20% (dry basis) prebloom alfalfa haylage to result in a 60: 40 ratio of forage to concentrate. In Experiment 2, 12 (X = 149 d of lactation) midlactation Holstein cows were fed diets containing 0 or 20% treated wheat straw to measure lactational performance during a 12-wk period. In Experiment 1, no effect of diet was observed on ruminal pH, osmolality, digestion of neutral detergent fiber of straw, or 4% fat-corrected milk. However, the dry matter intake of cows fed diets containing the two highest concentrations of treated straw was depressed and was associated with a significant body weight loss. The ruminal rate of passage of treated straw was not affected by diet; however, rate of passage of alfalfa haylage decreased when straw was included in the diet. In Experiment 2, no effect on cow performance was observed when straw treated with alkali was included at 20% of the diet. Inclusion of up to 20% wheat straw treated with 3% NaOH plus 3% Ca(OH)2 in diets of lactating cows resulted in ruminal function and performance that were similar to those of cows fed diets that contained alfalfa haylage only.

Animal Nutritional Physiological Phenomena↗
PubMed2006

Mistletoe alkali inhibits peroxidation in rat liver and kidney.

AIM: To explore the antioxidant and free radical scavenger properties of mistletoe alkali (MA). METHODS: The antioxidant effect of mistletoe alkali on the oxidative stress induced by carbon tetrachloride (CCl4) in rats was investigated. The rats were divided into four groups (n = 8): CCl4-treated group (1 mL/kg body weight), MA -treated group (90 mg/kg), CCl4+MA-treated group and normal control group. After 4 wk of treatment, the level of malondialdehyde (MDA), a lipid peroxidation product (LPO) was measured in serum and homogenates of liver and kidney. Also, the level of glutathione (GSH), and activities of glutathione reductase (GR), glutathione peroxidase (GSPx), superoxide dismutase (SOD), and glutathione-S-transferase (GST) in liver and kidney were determined. Scavenging effects on hydroxyl free radicals produced in vitro by Fenton reaction were studied by ESR methods using 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as a spin trap reagent and H2O2/UV as the OH. source. Urinary 8-hydroxydeoxyguanosine (8-OHdG) was determined by competitive ELISA. RESULTS: In CCl4-treated group, the level of LPO in serum of liver and kidney was significantly increased compared to controls. The levels of GSH and enzyme activities of SOD, GSPx and GR in liver and kidney were significantly decreased in comparison with controls. In CCl4+MA-treated group, the changes in the levels of LPO in serum of liver and kidney were not statistically significant compared to controls. The levels of SOD, GSPx and GR in liver and kidney were significantly increased in comparison with controls. There was a significant difference in urinary excretion of 8-OHdG between the CCl4-treated and MA-treated groups. CONCLUSION: Oxidative stress may be a major mechanism for the toxicity of CCl4. MA has a protective effect against CCl4 toxicity by inhibiting the oxidative damage and stimulating GST activities. Thus, clinical application of MA should be considered in cases with carbon tetrachloride-induced injury.

Animals↗
PubMed1999

[Early limbal autograft after alkali burn of the ocular surface].

Limbal autograft transplantation is recommended for treatment of limbal stem cell destruction and its complications. It is appropriate to restore corneal reepithelialization and arrest corneal vascularization and scarring. In unilateral alkali injury, limbal transplantation was first recommended for late management of corneal conjunctivalization. Our patient had severe ocular unilateral alkali injury. Early autologous limbal transplant was effective in restoring an excellent corneal surface and a good visual function.

Adult↗
PubMed1975

[Isolation and properties of a preparation of arterial collagen solubilized by pretreatment with alkali (author's transl)].

The acid-soluble, highly cross-linked aorta collagen, of which about 30% can be converted into a soluble form by alkali treatment, followed by extraction with aetic acid, was obtained predominantly in the form of monomeric, helical molecules, as indicated by the value for the intrinsic viscosity and its behaviour in sodium dodecylsulphate disc electrophoresis. Apart from decreased values for tyrosine (0.26%), arginine (4.4%) and aspartic acid (3.9%), the amino acid composition of the aorta collagen fraction was similar to that of the acid-soluble calf skin collagen. This finding, together with the cyanogen bromide peptide pattern, shows that the collagen extracted from the artery is predominantly type I. Treatment with alkali probably shortens the alpha1-CB6-peptide by about 45 amino acids. The collagen extracted from artery was compared with acid soluble skin collagen by sodium dodecylsulphate polyacrylamide electrophoresis. The arterial collagen showed a marked increase in the rations alpha1 to alpha2 (4:1), alpha to beta (3:1) and beta11 to beta12 (2.5:1). Compared with acid soluble skin collagen, the aorta collagen contained twice as much galactose and glucose (13.5 and 9.6 nmol/mg protein respectively), which are bound to hydroxylysine. 50% of the hydroxylysine residues are unsubstituted, 15% are present as galactosyl hydroxylysine, and 35% as glucosyl-galactosyl hydroxylysine. On the basis of its reported properties, arterial collagen obtained by the method of Fujii appears to be a suitable substrate for the study of the enzymic synthesis and enzymic degradation of hydroxylysine glycosides of native arterial collagen.

Amino Acids↗
PubMed2002

The application of pinch analysis to water, reagent and effluent management in a chlor-alkali facility.

South African industry is coming under increasing pressure to reduce the amount of freshwater it uses and the amount of effluent it produces. Water pinch is a cleaner production technique aimed at reducing the freshwater consumption and effluent production within a chemical complex. The design of water-reuse or water pinch networks as applied to the case study of a chlor-alkali complex is considered. Insights are provided into the analysis and formulation of problems for large-scale industrial systems and the application of present techniques and tools to the formulated problem is illustrated. The features of the problem posed by the chlor-alkali facility are discussed and the limitations of the present theory in dealing with this problem highlighted. The concepts of utility-waterpinch analysis and process-water pinch analysis are introduced.

Chemical Industry↗
PubMed2004

[Corneal combined amniotic membrane transplantation for early severe alkali chemical injury of the eye].

OBJECTIVE: To investigate the effect of lamella corneal transplantation combined amniotic membrane transplantation for the early severe alkali burns of eyes. METHODS: Twenty-three eyes with an over second-degree acute corneal alkali injury in 2 weeks were treated by lamella corneal transplantation combined amniotic membrane transplantation. After the operation the patients were treated with an intense and prolonged regimen of topical steroids and topical and systemic vitamin C. All patients were followed up for 6-12 months. RESULTS: Seven eyes were cornea transparent, 10 semi-transparent, and 6 opaque in the 23 eyes, respectively. The visual acuity of 3 eyes was better than 0.3, that of 5 eyes was between 0.25 to 0.1, and that of the other 15 eyes was below 0.1. No eye was enucleated due to the corneoscleral melting. CONCLUSION: Lamella corneal transplantation combined amniotic membrane transplantation may clear away the necrotic tissues and cells of corneal or conjunctiva, prevent and reduce the complication, and improve the prognosis of the patients.

Adolescent↗
PubMed2005

Isolation of 4-aminopyridine resistant mutants affecting alkali-insoluble glucan content of cell walls in Saccharomyces cerevisiae.

Saccharomyces cerevisiae cells when grown on synthetic medium plates containing 10 mM of 4-aminopyridine (4-AP) undergo cell lysis. Using an ethylmethane sulfonate mutagenesis (EMS) screen, 4-AP resistant mutants (apr) were isolated which could grow on inhibitory concentration of 4-AP. Eighty mutants were obtained that were recessive, monogenic and formed two complementation groups. To identify genes, whose products might be interacting with the apr loci, extragenic suppressors were isolated, which reverted 4-AP resistance phenotype of apr mutants. The suppressors, when genetically characterized, were found to be recessive and represented two loci with overlapping functions. Representative alleles from apr mutants were analyzed for cell wall composition. They were found to have a higher amount of alkali-insoluble glucan signifying the role of alkali-insoluble glucan in cell wall maintenance.

4-Aminopyridine↗
PubMed2005

[Expression of thrombospondin 2 during the repair process after alkali burn injury of cornea in mice].

OBJECTIVE: To explore the expression of thrombospondin 2 (TSP2) during the repair process after alkali burn injury to cornea in mice. METHODS: Forty mice were employed in the study. The murine corneal alkali burn model was reproduced (n = 35) as experimental group (E), and the mice were randomly divided into control (C, n = 5) and experimental (E, n = 35) groups. The mice in E group were again divided into 7 sub-groups according to different time points [3, 6, 12, 24, 48, 96 and 192 postburn hours (PBHs)] with 5 mice in each sub-group. HE staining, immunocytochemistry (ICC) and RT-PCR were employed to observe the expression of TSP2 in the corneal tissue of mice in both control and all animals in experimental sub-groups at all above mentioned time points (PBHs). RESULTS: TSP2 was expressed in corneal tissue in both C and E groups, especially in the basal layer of epithelial layer, and also a weak expression in substantia propria layer. Compared with that in C group (0.48 +/- 0.15), the expression of TSP2 in E group enhanced at 3 PBH, peaked at 6 PBH, (1.54 +/- 0.45, P < 0.05), dropped to the nadir at 24 PBH (0.73 +/- 0.19), and bounded back afterwards. It peaked again at 96 PBH (1.79 +/- 0.63, P < 0.05), then decreased thereafter, and approached the control level at 192 PBH (P > 0.05). There was remarkable angiogenesis in the cornea at 24 PBH in the mice in E group. CONCLUSION: The expressions of TSP2 exhibits fluctuating changes along with the course of repair. This might be related to the compensatory process under stress condition.

Animals↗
PubMed1991

Effect of topical corticosteroids on goblet-cell density in an alkali-burn model.

Conjunctival alkali burns result in a loss of goblet cells in the acute postinjury period. A deficiency of goblet cells and their primary product, mucin, is associated with both short- and long-term ocular sequelas. We evaluated the effect of topical corticosteroids on goblet-cell density in a prospective, randomized, controlled trial using 24 eyes of 12 adult albino rabbits in which a standard conjunctival burn was made. The treatment group was found to have 97.38 goblet cells per unit area of conjunctiva; the control group had 65.81 goblet cells per unit area of conjunctiva. This was a statistically significant difference (P less than .02). These results suggest that topical steroids are beneficial in suppressing goblet-cell loss after a conjunctival alkali burn.

Administration, Topical↗
PubMed1991

The effect of alkali light chains on the thermal stability of myosin subfragment 1.

Thermal denaturation of myosin subfragment 1 (S1) isoforms from rabbit skeletal muscle containing the different alkali light chains A1 and A2 [S1(A1) and S1(A2), respectively] were studied by various methods. Turbidity measurements showed that thermally induced (heating rate 1 degrees C min-1) aggregation of S1(A1) occurs at lower temperatures than that of S1(A2). However, the temperature dependences of the tryptophan fluorescence spectrum and that for ATPase inactivation were the same for S1(A1) and S1(A2). Thermal denaturation of the S1 isoforms was also studied by differential scanning microcalorimetry with the 'successive annealing' method. Three independently melting cooperative regions (domains) were revealed in the molecules of both isoforms. Heat sorption curves for the S1 isoforms were different only for the most thermolabile domain, which had a maximum at 36 degrees C for S1(A1) and at 40.5 degrees C for S1(A2). Two other peaks had maxima at 46-47 degrees C and 50-51 degrees C for both isoforms. It is proposed that alkali light chains A1 and A2 differently affect the conformation of the most thermolabile domain, which probably does not contain trytophan residues and does not take part directly in the formation of the active site of the S1 ATPase.

Animals↗
PubMed1978

Annealing of alkali-resistant HSV DNA strands and isolation of S and L components.

DNA isolated from highly purified virions of herpes simplex virus type-1 (HF strain) was denatured by centrifugation in alkaline sucrose gradients. DNA molecules corresponding to intact single-stranded virion DNA (50 x 10(6) daltons) were isolated and adjusted to neutral pH. The DNA was annealed under conditions permitting reassociation of intact single-stranded molecules and studied by electron microscopy. Three classes of DNA molecules showing double-stranded sequences were observed: (a) fully double-stranded DNA molecules the size of the intact HSV DNA genome, namely 52 micron; (b) DNA hybrids with a region of partial double-strandedness ranging from 5 to 12 micron, plus long single strands; and (c) DNA hybrids with a double-stranded region of 32--40 micron, plus short single strands. (These results suggest that the alkali-resistant single-stranded HSV DNA molecules are composed of several subclasses that permit annealing of either the total genome or the S or L components.) The 5 micron double-stranded region probably constitutes the S component of HSV DNA and the sequences longer than 5 micron and shorter than 12 micron represent annealing of the repeat sequences on either or both sides of the S component. The double-stranded sequences with a length of 32--40 micron may represent the L component. Treatment of the annealed, partially double-stranded hybrid DNA molecules with S1 endonuclease to remove the single-stranded termini and centrifugation in neutral sucrose gradients yielded two distinct peaks. Centrifugation of fractions from the two peaks in caesium chloride density gradients showed that the small DNA component (possibly the S and the repeat sequences) had a higher buoyant density and the longer (possibly the L) DNA component had a lower density than the HSV DNA marker. Annealing of alkali-resistant viral DNA strands therefore provides a means of isolating the L, S and repeat sequence regions of HSV DNA.

Base Sequence↗
PubMed1987

[Langerhans cells and corneal neovascularization in experimental alkali burns].

Experimental alkali-burns rabbit corneas present a neovascularisation. Six weeks later the corneas have been processed for ATPase Cytochemistry, allowing the observation of Langerhans cells. We observed an increase in the number of Langerhans cells that was statistically significant in alkali-burned corneas when compared to unburned corneas in the peripheral and midperipheral cornea.

Animals↗
PubMed1989

Influence of vitamin B2 on formation of chromium(V), alkali-labile sites, and lethality of sodium chromate(VI) in Chinese hamster V-79 cells.

The effect of vitamin B2 on the cellular reduction and cytotoxicity of chromate(VI) was studied using Chinese hamster V-79 cells. Electron spin resonance studies showed that incubation of cells with Na2CrO4 resulted in the formation of both chromium(V) and chromium(III) complex and that cellular pretreatment with riboflavin (Vitamin B2) for 24 h prior to exposure increased the level of chromium(V) complex, but the level of chromium(III) remained unchanged. Analysis of flavin derivatives revealed that pretreatment with vitamin B2 increased free riboflavin without altering flavin adenine dinucleotide and flavin mononucleotide. In addition, the level of the flavoenzyme glutathione reductase, which is capable of reducing chromate, was unaffected by pretreatment with vitamin B2. However, treatment of cells with vitamin B2 and Na2CrO4 augmented the inhibition of glutathione reductase attributable to Na2CrO4 alone. Using a colony-forming assay, pretreatment with vitamin B2 resulted in a decrease of cytotoxicity after exposure to the lethal concentration of chromate (15 microM) but did not affect the cytotoxicity at sublethal concentration of this metal (5-7.5 microM). Alkaline elution studies demonstrated that Na2CrO4 induced alkali-labile sites in the DNA of cells in a concentration-dependent manner (5-15 microM) and pretreatment with vitamin B2 resulted in an increase of these DNA lesions at all concentrations of Na2CrO4. The results, showing that vitamin B2 enhances chromate-induced alkali-labile lesions and chromium inhibition of glutathione reductase, might be due to an increase of chromium(V) species, possibly through its ability to directly reduce chromium(VI). The results also suggest that the extent of DNA lesions induced by chromate may not correlate directly with the cytotoxic effects of this metal.

Animals↗
PubMed1989

Human ventricular/slow twitch myosin alkali light chain gene characterization, sequence, and chromosomal location.

The gene coding for the human ventricular/slow twitch myosin alkali light chain isoform was isolated and sequenced. It was found to contain a total of seven exons, the last of which is completely 3'-untranslated sequence. Comparison of this gene sequence with that of the various fast twitch skeletal isoform gene sequences revealed that the exon-intron arrangement is conserved within the myosin alkali light chain gene family. In fact the introns are in exactly the same positions within analogous codons. Comparison of the derived amino acid sequence from the human ventricular/slow twitch isoform gene with that of other isoform protein sequences indicated that the protein encoded by this gene is more homologous to the chicken cardiac isoform protein sequence than to any of the other protein sequences. These results indicate that the gene duplication which gave rise to the ventricular/slow twitch and fast twitch isoform genes must have occurred prior to the divergence of mammals and avians. We have also localized the human ventricular/slow twitch isoform gene to the short arm of human chromosome 3. Interestingly the corresponding mouse gene has been mapped to the distal region of mouse chromosome 9 which contains a conserved syntenic group of genes that map to the short arm of human chromosome 3.

Amino Acid Sequence↗
PubMed1987

Treatment with dilute alkali-nuclease S1 permits the analysis of DNA damage: cells treated with platinum analogues.

We describe here an approach to characterize various lesions induced in DNA by drug treatments, using three parameters: (a) release of single-stranded DNA fragments by cell lysis in dilute alkali, which result from enzymatic strand scission during DNA repair or chemical alterations of DNA; (b) the presence of high molecular weight DNA in cells after lysis in dilute alkali followed by nuclease S1 treatment which, due to drug-induced DNA cross-links and its level is a measure of the amount of DNA-containing cross-links; and (c) the appearance of small double-stranded DNA fragments, when the cell lysis is followed by digestion with nuclease S1 to remove single-stranded DNA. This DNA shows the same characteristics as DNA of untreated cells, but it may contain monoadducts. By following the flow of label through the three parameters, one can characterize both the lesions induced in DNA and how the lesions are repaired. We report here results of three platinum analogues: cis-Pt(II), trans-Pt(II), and cis-FLAP(II). A large proportion of DNA in treated cells appears as fragments (parameter c). The cis- compounds and trans- compounds differ with regard to appearance of high molecular weight DNA (parameter b) and the initial release of fragments (parameter a).

Cell Line↗