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Lee Hui-Ling - - 2008
A major carcinogen, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), is present in cigarette smoke and its metabolite, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), is used as an exposure biomarker for environmental tobacco smoke (ETS). This metabolite (NNAL) can be either detoxified into glucuronidated NNAL (NNAL-Gluc) or activated into an unstable reactive metabolite that methylates DNA along with formation ...
Tran Thuy A - - 2008
The effects of polar (mercaptoacetyl-triseryl) and negatively charged (mercaptoacetyl-triglumatyl) chelators on the biodistribution of 99mTc-labeled anti-HER2 Affibody molecules were previously investigated. With glycine, serine, and glutamate, we demonstrated that substitution with a single amino acid in the chelator can significantly influence the biodistribution properties and the excretion pathways. Here, we ...
Biver Sophie - - 2008
The kidney has an important role in the regulation of acid-base homeostasis. Renal ammonium production and excretion are essential for net acid excretion under basal conditions and during metabolic acidosis. Ammonium is secreted into the urine by the collecting duct, a distal nephron segment where ammonium transport is believed to ...
Fenton Tanis R - - 2008
BACKGROUND: The acid-ash diet hypothesis of osteoporosis suggests that acid from the modern diet causes a demineralization of the skeleton, and mobilized bone calcium is excreted. A systematic approach has not been used to summarize the findings of the numerous studies about the hypothesis. OBJECTIVES: The purpose of this meta-analysis ...
Shih Tin-Han - - 2008
The mechanism of ammonia excretion in freshwater teleosts is not well understood. In this study, scanning ion-selective electrode technique was applied to measure H(+) and NH(4)(+) fluxes in specific cells on the skin of zebrafish larvae. NH(4)(+) extrusion was relatively high in H(+) pump-rich cells, which were identified as the ...
Yap Ivan K S - - 2008
The effects of the antibiotic vancomycin (2 x 100 mg/kg/day) on the gut microbiota of female mice (outbred NMRI strain) were studied, in order to assess the relative contribution of the gut microbiome to host metabolism. The host's metabolic phenotype was characterized using (1)H NMR spectroscopy of urine and fecal ...
Kenyon E M - - 2008
The relationship of exposure and tissue concentration of parent chemical and metabolites over prolonged exposure is a critical issue for chronic toxicities mediated by metabolite(s) rather than parent chemical alone. This is an issue for AsV because its trivalent metabolites have unique toxicities and relatively greater potency compared to their ...
Li Wei - - 2009
Microorganisms influence the dissolution of a number of minerals. Limestone is one of the most abundant rock types in karst areas, and is predominantly calcium carbonate. Two types of experimental systems were designed in this paper, to make comparisons of limestone dissolution rate among the acidic materials and extracellular carbonic ...
Diesveld Ramon - - 2009
L-Threonine is an important biotechnological product and Corynebacterium glutamicum is able to synthesize and accumulate this amino acid to high intracellular levels. We here use four exporters of Escherichia coli and show that three of them operate in C. glutamicum, with RhtA and RhtC being the most effective. Whereas RhtA ...
Okuno Alato - - 2008
Some people may take excessive tryptophan as a supplement in the expectation that the tryptophan metabolite, melatonine, will help to induce sufficient sleep. We investigated the basis for a useful index to assess the risk of a tryptophan excess. Young rats were fed on a 20% casein diet with 0, ...
Stepanov Irina I The Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA. - - 2008
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a potent lung carcinogen present in both unburned tobacco and cigarette smoke. The sum of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) and its glucuronides, referred to as total NNAL, is an established urinary biomarker of human NNK uptake. Metabolic activation of NNK to DNA adducts proceeds via alpha-hydroxylation pathways, and 4-oxo-4-(3-pyridyl)butanoic ...
Moriwaki Y - - 2008
Sucrose is converted fructose and glucose, which may increase plasma uric acid concentration (pUA) through increased purine degradation and/or decreased uric acid (UA) excretion. To investigate effects of acarbose, an inhibitor of alpha-glucosidase, on the increased pUA from sucrose administration, we measured pUA and urinary UA excretion in 6 healthy ...
Ward Natalie C - - 2008
Arachidonic acid is a major fatty acid that can be metabolized by the cytochrome P450 enzyme to a number of bioactive eicosanoids. A major metabolite of this oxidation is 20-hydroxyeicosatetraenoic acid, which acts as a potent vasoconstrictor. However, in the kidney, its vasoconstrictor actions can be offset by its natriuretic ...
Lubis Harun Rasyid - - 2008
Among the various ways of managing poisoning, haemodialysis may help in enhancing excretion of the toxic substance. We report a case, a Russian male, 35 years old, who was rushed to the Gleneagles Hospital Medan from the airport after being evacuated from Banda Aceh together with another older Russian who ...
Kirchheiner Julia - - 2008
The cytochrome P450 enzymes CYP2C8, CYP2C9 and CYP2J2 generate 8,9-, 11,12-, and 14,15-epoxyeicosatrienic acid (EET) from arachidonic acid, and these EETs are then hydrolyzed to dihydroxyeicosatrienoic acids (DHET) before excretion into the urine. It is unknown how genetic polymorphisms affect formation of these diuretic, vasodilatory and anti-inflammatory eicosanoids, and whether ...
Rylander Ragnar - - 2008
Several epidemiological investigations over the last 50 y have demonstrated a relation between risk for cardiovascular disease and drinking water hardness or its content of magnesium and calcium. An additional parameter, first suggested in a study from Japan 50 y ago, is the acidity of the water. It is known ...
Sebolai Olihile M - - 2008
In this paper we report the influence of acetylsalicylic acid on oxylipin migration in Cryptococcus neoformans var. neoformans UOFS Y-1378, previously isolated from human bone lesion. Transmission electron microscopy suggests that osmiophilic material originates in mitochondria and is deposited inside the yeast cell wall, from which it is excreted into ...
Evans Craig - - 2008
Autism is a complex and life-long behavioural disorder of unknown aetiology. Recent reports have indicated the involvement of digestive tract dysfunction and possible complications from inadequate nutrition. In this study, 34 autistic children (12 untreated and 22 receiving therapeutic treatments related to digestive function and nutritional uptake) and 29 control ...
Kos Mojca Kerec - - 2008
Chitosan significantly increases the permeability of the isolated pig urinary bladder wall by causing urothelial desquamation, the extent of which depends also on the concentration of the polymer. By desquamation permeability barriers of the urothelium are removed. To gain additional insight into the mechanism by which chitosan acts an absorption ...
Reeves W Brian - - 2008
Acute kidney injury is an important complication in hospitalized patients often diagnosed late and associated with high mortality and morbidity. Although biomarkers for nephrotoxicity are available, they often lack sensitivity and specificity for detecting tubular injury. Netrin-1 is a laminin-like molecule highly expressed in many organs including kidney. To determine ...
Lindner Holger A - - 2008
Mammalian aminoacylase-1 (Acy1) participates in the breakdown of N-acetylated amino acids during intracellular protein catabolism. Acy1 is most abundantly expressed in the kidney tubular epithelium. Lately, Acy1 deficiency was identified in children with increased urinary excretion of several N-acetylamino acids. Here we report detailed N-acetylamino acid specificity profiles for human ...
Lam Marnix G E H - - 2008
PURPOSE: (153)Sm-ethylenediaminetetramethylenephosphonic acid (EDTMP; Quadramet) is indicated for the treatment of painful bone metastases, whereas zoledronic acid (Zometa) is indicated for the prevention of skeletal complications. Because of the different therapeutic effects, combining the treatments may be beneficial. Both, however, accumulate in areas with increased osteoblastic activity. Possible drug interactions ...
Xie Xiaofeng - - 2007
A sensitive flow injection chemiluminescence method, based on the inhibitory effect of chlorogenic acid on the reaction between luminol and dissolved oxygen, was presented for the determination of chlorogenic acid. It was found that the decrease of chemiluminescence intensity was linear with the logarithm of chlorogenic acid concentration over the ...
Gamelin Laurence - - 2007
PURPOSE: Oxaliplatin displays a frequent dose-limiting neurotoxicity due to its interference with neuron voltage-gated sodium channels through one of its metabolites, oxalate, a calcium chelator. Different clinical approaches failed in neurotoxicity prevention, except calcium-magnesium infusions. We characterized oxalate outcome following oxaliplatin administration and its interference with cations and amino acids. ...
Kim Sungkyoon - - 2007
Using generalized linear models with natural-spline smoothing functions, we detected effects of specific xenobiotic metabolizing genes and gene-environment interactions on levels of benzene metabolites in 250 benzene-exposed and 136 control workers in Tianjin, China (for all individuals, the median exposure was 0.512 p.p.m. and the 10th and 90th percentiles were ...
Atoui A - - 2007
AIMS: Aspergillus carbonarius is an important ochratoxin A (OTA)-producing fungus which is responsible for toxin contamination of grapes and wine. The objectives of this study were to examine the partitioning of OTA in mycelium and conidia of a range of A. carbonarius strains on artificial grape juice and defined media, ...
Barr Dana B - - 2007
Atrazine (ATZ) is the second most abundantly applied pesticide in the United States. When we assessed exposure to ATZ by measuring its urinary mercapturic acid metabolite, general population data indicated that < 5% of the population was exposed to ATZ-related chemicals (limit of detection < 0.8 ng/mL). The aim of ...
Wagner Carsten A - - 2007
PURPOSE OF REVIEW: Metabolic acidosis is a severe disturbance of extracellular pH homeostasis that can be caused both by inborn or acquired defects in renal acid excretion or metabolic acid production. Chronic metabolic acidosis causes osteomalacia with nephrocalcinosis and urolithiasis. In the setting of end-stage renal disease, metabolic acidosis is ...
Niblett Suzanne H - - 2007
Patients with chronic fatigue syndrome (CFS) have a broad and variable spectrum of signs and symptoms with variable onsets. This report outlines the results of a single-blind, cross-sectional research project that extensively investigated a large cohort of 100 CFS patients and 82 non fatigued control subjects with the aim of ...
Mani Ali R - - 2007
During inflammation, neutrophil- and monocyte-derived myeloperoxidase catalyzes the formation of hypochlorous acid, which can chlorinate tyrosine residues in proteins to form chlorotyrosine. However, little is known of the metabolism and disposition of chlorotyrosine in vivo. Following infusion of deuterium-labeled [D(4)]chlorotyrosine into Sprague-Dawley rats, the major urinary metabolites were identified by ...
Kim Hye-Young - - 2007
Kidneys can maintain acid-base homeostasis, despite reduced renal mass, through adaptive changes in net acid excretion, of which ammonia excretion is the predominant component. The present study examines whether these adaptations are associated with changes in the ammonia transporter family members, Rh B glycoprotein (Rhbg) and Rh C glycoprotein (Rhcg). ...
Bakhiya Nadiya - - 2007
Excretion of mercapturic acids of a xenobiotic is a good indicator for the formation of electrophilic intermediates. However, the route of excretion, urine or feces, is important for usage of a given mercapturic acid as a biomarker in humans. In the present study we investigated the excretion routes of 1-methylpyrenyl ...
Mao I F - - 2007
The purpose of this study was to investigate whether the metabolic suppression of hippuric acid (HA) occurs in field workers coexposed to toluene, xylene and ethyl benzene. Eleven male spray painters were recruited into this study and monitored for 2 weeks using a repeated-measures study design. The sampling was conducted ...
Zhen Yueying - - 2007
Peroxisome proliferator-activated receptor alpha (PPARalpha) is a nuclear receptor with manifold effects on intermediary metabolism. To define a set of urinary biomarkers that could be used to determine the efficacy of PPARalpha agonists, a metabolomic investigation was undertaken in wild-type and Pparalpha-null mice fed for 2 wk either a regular ...
Brosnan Margaret E - - 2007
The urinary excretion of orotic acid, an intermediate in the pyrimidine biosynthetic pathway, is markedly increased in many inborn errors of the urea cycle and in a number of other disorders involving arginine metabolism. Carbamoyl phosphate, which accumulates within hepatic mitochondria in patients with ornithine transcarbamoylase deficiency, can diffuse to ...
Thiesen Flavia Valladão - - 2007
Toluene is the main substance contained in products used as inhalants. The frequent abuse of toluene-based inhalants requires the definition of a simple laboratory parameter that allows acute exposure assessment. This study aimed at defining urinary hippuric acid (UHA) levels related to intentional exposure to toluene, and to correlate them ...
Gilmour K M - - 2007
African lungfish Protopterus annectens utilized both respiratory and metabolic compensation to restore arterial pH to control levels following the imposition of a metabolic acidosis or alkalosis. Acid infusion (3 mmol kg(-1) NH(4)Cl) to lower arterial pH by 0.24 units increased both pulmonary (by 1.8-fold) and branchial (by 1.7-fold) ventilation frequencies ...
Gu Liwei - - 2007
Sorghum bran is concentrated with procyanidins (predominately polymers), which may be beneficial for health in humans; however, the bioavailability of procyanidins is not well-understood. Female Sprague-Dawley rats were fed an AIN93G diet containing 0, 5, 10, 20, or 40% Hi-tannin sorghum bran (n = 5-7 for each group) for 50 ...
Koskela Anja - - 2007
BACKGROUND: Whole-grain rye and wheat cereals contain high amounts of alkylresorcinols (ARs), phenolic lipids. ARs can be quantified in plasma. Two recently identified urinary AR metabolites, 3,5-dihydroxyphenylbenzoic acid (DHBA) and 3-(3,5-dihydroxyphenyl)-1-propanoic acid (DHPPA), may be useful as biomarkers of intake of whole-grain rye and wheat. METHODS: We evaluated 4 pretreatment ...
Karanam Bindhu - - 2007
[(3R)-4-(4-Chlorobenzyl)-7-fluoro-5-(methylsulfonyl)-1,2,3,4-tetrahydrocyclopentaindol-3-yl]acetic acid (MK-0524) is a potent orally active human prostaglandin D(2) receptor 1 antagonist that is currently under development for the prevention of niacin-induced flushing. The metabolism and excretion of [(14)C]MK-0524 in humans were investigated in six healthy human volunteers following a single p.o. dose of 40 mg (202 microCi). ...
Stehberger Paul A PA Institute of Physiology and Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, - - 2007
Mutations in the human gene that encodes the AE1 Cl(-)/HCO(3)(-) exchanger (SLC4A1) cause autosomal recessive and dominant forms of distal renal tubular acidosis (dRTA). A mouse model that lacks AE1/slc4a1 (slc4a1-/-) exhibited dRTA characterized by spontaneous hyperchloremic metabolic acidosis with low net acid excretion and, inappropriately, alkaline urine without bicarbonaturia. ...
Zhang Yu - - 2007
The metabolism of flavone C-glucosides and p-coumaric acid from antioxidant of bamboo leaves (AOB) in rats is discussed systematically in the present study. Following single oral administration of AOB, p-coumaric acid was detected in plasma but not in gastrointestinal tract extracts and faeces, and the corresponding absorption pharmacokinetic curve at ...
Berndt Theresa J TJ Department of Internal Medicine, Mayo Clinic College of Medicine, Mayo Clinic Rochester, 200 First Street SW, Rochester, MN 55905, - - 2007
The phosphaturic activity of intact, full-length, fibroblast growth factor-23 (FGF-23) is well documented. FGF-23 circulates as the intact protein and as fragments generated as the result of proteolysis of the full-length protein. To assess whether short fragments of FGF-23 are phosphaturic, we compared the effect of acute, equimolar infusions of ...
Pais Vernon M VM Jr Division of Urology, University of Kentucky Chandler Medical Center, Lexington, Kentucky 40536, USA. - - 2007
Hyperuricosuria is a well-recognized risk factor for calcium oxalate urolithiasis. Some studies have demonstrated elevated urinary uric acid excretion in stone formers compared with non-stone-forming controls; nevertheless, these studies were limited by patient consumption of self-selected diets. With the recognition that dietary differences may induce variations in urinary uric acid ...
Dawson-Hughes B - - 2007
In 30 adults, increasing intake of aromatic amino acids increased calcium excretion and serum IGF-1, but not indices of bone turnover, when compared with similar increases in intake of branched-chain amino acids. The mechanisms involved are not certain but these findings suggest a role for the calcium sensor receptor. INTRODUCTION: ...
Wijnhoven Tessa J M - - 2007
Heparan sulfates (HS) are long, unbranched, negatively charged polysaccharides that are bound to core proteins. HS in the glomerular basement membrane (GBM) is reported to be important for charge-selective permeability. Aberrant GBM HS expression has been observed in several glomerular diseases, such as diabetic nephropathy and membranous glomerulopathy, and a ...
Wesson D E - - 2007
Dietary protein as casein (CAS) augments intrinsic acid production, induces endothelin-mediated kidney acidification, and promotes kidney injury. We tested the hypothesis that dietary CAS induces endothelin-mediated kidney injury through augmented intrinsic acid production. Munich-Wistar rats ate minimum electrolyte diets from age 8 to 96 weeks with 50 or 20% protein ...
Ye Xiaoyun - - 2006
Parabens appear frequently as antimicrobial preservatives in cosmetic products, in pharmaceuticals, and in food and beverage processing. In vivo and in vitro studies have revealed weak estrogenic activity of some parabens. Widespread use has raised concerns about the potential human health risks associated with paraben exposure. Assessing human exposure to ...
Kuhnt Katrin - - 2006
BACKGROUND: High consumption of trans fat has been associated with high oxidative stress in humans, which could increase the risk of the development or acceleration of several diseases, such as atherosclerosis, cancer, and type 2 diabetes. OBJECTIVE: Several urinary and blood biomarkers of oxidative stress [8-iso-prostaglandin-F(2alpha) (PGF(2alpha)), 15-keto-dihydro-PGF(2alpha), and 7,8-dihydro-8-oxo-2'-deoxy-guanosine ...
Tay Yi L - - 2006
The climbing perch, Anabas testudineus, inhabits large rivers, canals, stagnant water bodies, swamps and estuaries, where it can be confronted with aerial exposure during the dry season. This study aimed to examine nitrogen excretion and metabolism in this fish during 4 days of emersion. Contrary to previous reports, A. testudineus ...
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