Polycyclic aromatic hydrocarbons (PAH`s) are ubiquitous hydrophobic organic pollutants in the marine environment. Many of the PAM`s are classified as possible carcinogens or mutagens, therefore they are of considerable concern to human and environmental health. The highest concentrations are found in coastal regions due to anthropogenic activities including oil spills, tanker operations, incomplete fossil fuel combustion and runoff. The sources and distribution of PAM`s in sediments are fairly well known, while the fate and transport of PAH`s in the marine environment are less known. Desorption is an important factor influencing the fate and transport of hydrophobic molecules at the seawater/sediment interface. The desorption of PAH`s from contaminated marine sediments to the water column/pore water affects the availability of the pollutant to biota. The sorption of PAH`s is determined in part by the ...
Polycyclic aromatic hydrocarbons (PAHs) are ubiquious in the environment both as natural products and as environmental contaminants. Among PAHs, phenanthrene (PH) that is ubiquitously distributed throughout the environment was subjected in this study. Although environmental distribution and metabolism of PH have been well reported, there are only a few studies examined the expression of mRNA and their functions on PH-induced toxicity. A new paradigm in toxicity screening, toxicogenomic technology represents a useful approach for evaluating the toxic properties of environmental pollutants. In this respect, we elicited the genes which were changed more than 2-fold by analysis of gene expression profiles in human hepatocellular carcinoma (HepG2) cells, exposed to PH by using human oligonucleo...
The PAH (polycyclic aromatic hydrocarbons) concentration in coastal zones in the Arctic were studied. Assessment in remote areas is difficult because PAHs contamination from fossil fuel discharges and combustion can be masked by PAHs from natural sources, such as oil seeps, bitumens and forest fires. It is believed that the most important source of anthropogenic PAHs in the Arctic is the long range transport of combustion emissions. A comparison study of PAH distribution between the Beaufort Sea and the Barents Sea led to the interpretation of PAH distributions in terms of potential sources and their geochemistry. PAH concentrations in the Barents Sea sediments were found to be 2 to 20 times lower than in the Beaufort Sea sediments; they are believed to be from anthropogenic sources. In the Beaufort ...
Abstract Lysis and extraction of cells are essential sample processing steps for investigations pertaining to metabolism of xenobiotics in cell culture studies. Of particular importance to these procedures are maintaining high lysis efficiency and analyte integrity as they influence the qualitative and quantitative distribution of drug and toxicant metabolites in the intra- and extracellular milieus. In this study we have compared the efficiency of different procedures viz. homogenization, sonication, bead beating, and molecular grinding resin treatment for disruption of HT-29 colon cells exposed to benzo(a)pyrene (BaP), a polycyclic aromatic hydrocarbon (PAH) compound and a suspected colon carcinogen. Also, we have evaluated the efficiency of various procedures for extracting BaP parent c...
Chemoheterotrophic thermophilic bacteria were used to achieve enhanced hydrocarbon degradation during slurry-phase treatment of oily waste sludges from petroleum refinery operations. Aerobic and anaerobic bacterial cultures were examined under thermophilic conditions to assess the effects of mode of metabolism on the potential for petroleum hydrocarbon degradation. The study determined that both aerobic and anaerobic thermophilic bacteria are capable of growth on petroleum hydrocarbons. Thermophilic methanogenesis is feasible during the degradation of hydrocarbons when a strict anaerobic condition is achieved in a slurry bioreactor. Aerobic thermophilic bacteria achieved the largest apparent reduction in chemical oxygen demand, freon extractable oil, total and volatile solid,s and polycyclic aromatic hydrocarbons (PAHs) when treating oily waste sludges. The observed shift with time in the molecular weight distribution of ...
Chemoheterotrophic thermophilic bacteria were used to achieve enhanced hydrocarbon degradation during slurry-phase treatment of oily waste sludges from petroleum refinery operations. Aerobic and anaerobic bacterial cultures were examined under thermophilic conditions to assess the effects of mode of metabolism on the potential for petroleum hydrocarbon degradation. The study determined that both aerobic and anaerobic thermophilic bacteria are capable of growth on petroleum hydrocarbons. Thermophilic methanogenesis is feasible during the degradation of hydrocarbons when a strict anaerobic condition is achieved in a slurry bioreactor. Aerobic thermophilic bacteria achieved the largest apparent reduction in chemical oxygen demand, freon extractable oil, total and volatile solid,s and polycyclic aromatic hydrocarbons (PAHs) when treating oily waste sludges. The observed shift with time in the molecular weight distribution of ...
The research project had the aim to develop a standard for measuring individual, inner stresses from polycyclic aromatic hydrocarbons (PAHs) at work. The employed method was by characterizing PAHs and metabolites of PAHs to be identified in urine with a view to developing a biological monitoring of professionally exposured persons. Using a number of PAHs relevant to work, the following questions were studied in cell culture systems and different animal-experimental models: Which metabolites are formed from the PAHs used in cell culture systems and the different animal-experimental models, and what are their ratios in percent? What percentage of a PAH is excreted by experimental animals in their urine and faeces on the first, second, and third day following different forms of application? What is the scale of the individual range of variation ...
The use of municipal sewage sludge as a fertilizer in agriculture is a convenient method of disposal. However, sludge is often contaminated with toxic organic compounds such as dioxins, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs), with implications for soil fertility and quality of crops for human and animal consumption. These compounds can be assimilated by intact plants or in-vitro cell-Culture systems. The amount of uptake depends on the plant species and on the physico-chemical conditions that influence, for example, molecular configuration; uptake rates are higher with low-molecular-weight and polar compounds. The xenobiotic can be converted to polar conjugates and hydroxylated metabolites that may also be toxic. In some cases, large amounts of the compound and/or its metabolic products are incorporated into non-extractable residues. The bound residues, especially those associated with carbohydrate ...
Polycyclic aromatic hydrocarbons (PAHs) are combustion products of organic materials, mixtures of which contain multiple known and probable human carcinogens. PAHs occur in indoor and outdoor air, as well as in char-broiled meats and fish. Human exposure to PAHs occurs by inhalation, ingestion and topical absorption, and subsequently formed metabolites are either rendered hydrophilic and excreted, or bioactivated and bound to cellular macromolecules. The formation of PAH-DNA adducts (DNA binding products), considered a necessary step in PAH-initiated carcinogenesis, has been widely studied in experimental models and has been documented in human tissues. This review describes immunohistochemistry (IHC) studies, which reveal localization of PAH-DNA adducts in human tissues, and semi-quantify PAH-DNA ...
The research project had the aim to develop a standard for measuring individual, inner stresses from polycyclic aromatic hydrocarbons (PAHs) at work. The employed method was by characterizing PAHs and metabolites of PAHs to be identified in urine with a view to developing a biological monitoring of professionally exposured persons. Using a number of PAHs relevant to work, the following questions were studied in cell culture systems and different animal-experimental models: Which metabolites are formed from the PAHs used in cell culture systems and the different animal-experimental models, and what are their ratios in percent What percentage of a PAH is excreted by experimental animals in their urine and faeces on the first, second, and third day following different forms of application What is the scale of the individual range of variation ...
Studies were conducted in northern Bohemia to simultaneously evaluate personal exposures to air pollution in the form of respirable particles containing polycyclic aromatic hydrocarbons (PAHs) and biomarkers...Full Text Available
Cytochrome P450 1B1 (Cyp1b1) metabolism contributes to physiological functions during embryogenesis, but also to carcinogenic activation of polycyclic aromatic hydrocarbons (PAH). We generated...Full Text Available
Finding environmentally friendly and cost-effective methods to remediate soils contaminated with polycyclic aromatic hydrocarbons (PAHs) is currently a major concern of researchers. In this study, a series of small-scale semi-continuous extractions - with and without in situ wet oxidation - were performed on soils polluted with PAHs, using subcritical water (i.e. liquid water at high temperatures and pressures, but below the critical point) as the removal agent. Experiments were performed in a 300 mL reactor using an aged soil sample. To find the desorption isotherms and oxidation reaction rates, semi-continuous experiments with residence times of 1 and 2 h were performed using aged soil at 250 deg. C and hydrogen peroxide as oxidizing agent. In all combined extraction and oxidation flow experiments, PAHs in the remaining soil after the experiments were almost undetectable. In combined extraction and ...
Findings indicate an urgent need to establish a monitoring program for persistent organic pollutants in water and sediment. - Marine culture is thriving in China and represents a major component of the regional economy in coastal zones, yet the environmental quality of many of those areas has never been studied. This paper attempts to investigate the quality status of Daya Bay, a key aquaculture area in China. The levels of 16 polycyclic aromatic hydrocarbons (PAHs) were determined in water and sediment samples of the bay. The total concentrations of 16 PAHs varied from 4228 to 29325 ng l"-"1 in water, and from 115 to 1134 ng g"-"1 dry weight in sediments. In comparison to many other marine systems studied, the PAH levels in Daya Bay waters were relatively high, and at six sites they were sufficiently high (>10 #mu#g l"-"1) to cause acute toxicity. The PAH ...
A monitoring campaign of polychlorinated dibenzo-p-dioxins and dibenzofurans, polyaromatic hydrocarbons (PAHs), and polychlorinated biphenyl was carried out in an Italian iron ore sintering plant by sampling the combustion gases at the electrostatic precipitator (ESP) outlet, at the Wetfine scrubber (WS) outlet, and by collecting the ESP dust. Few data are available on these micropollutants produced in iron ore sintering plants, particularly from Italian plants. This study investigates the PAH emission profiles and the removal efficiency of ESPs and WS. PAHs were determined at the stack, ESP outlet flue gases, and in ESP dust to characterize the emission profiles and the performance of the ESP and the WS for reducing PAH emission. The 11 PAHs monitored are listed in the Italian legislative decree 152/2006. The mean total PAH sum ...
BackgroundGenome-scale metabolic reconstructions have been recognised as a valuable tool for a variety of applications ranging from metabolic engineering to evolutionary studies....Full Text Available
Proper assessment of the hypothesis which correlates polycyclic aromatic hydrocarbons (PAHs) with the unidentified infrared emission bands requires additional experimental laboratory data. In order to address this need, thermal infrared emission studies were performed on a subset of PAHs suggested to be of astrophysical importance. It was proposed that infrared emission from interstellar PAHs occurs following absorption of an ultraviolet photon. Since energy transfer to the ground electronic state can be rapid for a species in which intersystem crossing is negligible, the emission spectrum may be viewed as resulting from an equilibrium vibrational temperature (Leger and d'Hendecourt, 1987). This has been the basis for using infrared absorption spectra to calculate the corresponding emission spectra at various temperatures. These calculations were made using room temperature infrared absorption ...
To evaluate the contribution of genetic influences on the individual variation in plateau serum salicylate levels, salicylate metabolism was studied in seven pairs of identical and six pairs of fraternal...Full Text Available
Few studies have examined energy metabolism during prolonged, strenuous exercise. We wanted therefore to investigate energy metabolic consequences of a prolonged period of continuous strenuous work...Full Text Available
Several enzymes of the metabolic pathways responsible for metabolism of cytosolic ribonucleotides and deoxyribonucleotides are located in mitochondria. Studies described in this paper suggest dysfunction of the mitochondria to affect these metabolic pathways and limit the available levels of cytosolic ribonucleotides and deoxyribonucleotides, which in turn can result in aberrant RNA and DNA synthesis. Mitochondrial dysfunction has been linked to genomic instability, and it is possible that the limiting effect of mitochondrial dysfunction on the levels of nucleotides and resulting aberrant RNA and DNA synthesis in part can be responsible for this link. This paper summarizes the parts of the metabolic pathways responsible for nucleotide metabolism that can be affected by mitochondrial dysfunction.
Soluble TWEAK is a member of the TNF-alpha family of cytokines that has been shown to predict mortality in patients with heart failure. Pulmonary artery hypertension is a devastating disease, in which right ventricular function has been shown to be the major determinant of prognosis. In this hypothesis-generating study, we sought to evaluate the potential usefulness of sTWEAK in the prediction of disease severity in patients with pulmonary artery hypertension. We therefore conducted a retrospective analysis of sTWEAK serum levels in 95 stable patients with PAH. For all patients data on hemodynamic parameters, biomarkers and functional exercise tests were available. Compared to controls, patients with PAH showed significantly decreased levels of sTWEAK [median 314?pg/ml (interquartile range...
This is the first time that the adsorption of binary mixtures of polycyclic aromatic hydrocarbons (PAHs) has been studied. This study was carried out at laboratory scale in an experimental apparatus specially designed for this aim: with gas-phase fluorescence, a new detection procedure was used. Experimental conditions, mainly in terms of temperature (150C) and contaminant concentration (approximately 1 ppmv), close to the ones observed in energy generation systems, were applied. The PAH adsorption process interpretation was carried out by recording the experimentally obtained breakthrough curves. After the detection parameter optimization, the influence of adsorbate characteristics in the hot gas cleaning of PAH was studied. In this system, the adsorption of 10 binary mixtures of five PAH (naphthalene (Np), fluorene (Fu), phenanthrene ...
1. The excretion of para-aminohippurate (PAH) in the isolated perfused rat kidney was examined over a wide range of perfusate PAH concentrations (15 microM to 6 mM). PAH excretion increased steadily...Full Text Available
Slide 10 Slide 11 23 ground-floor apartments Ancillary Information Gathered Median total PAH [mg/g] Slide 15 What are the principal sources of PAHs to urban lakes?...
Contaminated wood treatment sites can result in adverse health effects to nearby residents. Environmental exposure can be estimated by measuring concentrations of pollutants in air, water, food, or wipe tests. This environmental exposure value can be used as a surrogate to estimate individual exposure. The objective of this study was to determine whether or not pentachlorophenol (PCP) could be found in potentially exposed residents and if the dioxin levels are consistent with PCP exposure. A further objective of the study was to determine whether or not PAH-DNA adducts could be found in the potentially exposed residents. We present results of biomonitoring studies in residents living near a wood treatment plant that used coal-derived creosote and PCP to process and treat wood for over 100 years. The plant was built in 1904 and used creosote and PCP. Creosote is a complex mixture that contains numerous ...
Chronically elevated interleukin-6 (IL-6) affects lipid and lipoprotein metabolism. Individuals genetically predisposed to higher IL-6 secretion may be at risk of dyslipidemia, especially during the...Full Text Available
The metabolism of [1,4-14C]putrescine and [terminal methylene-3H]spermidine was studied in the fruit pericarp (breaker stage) discs of tomato (Lycopersicon esculentum...Full Text Available
As part of the study of cytokinin metabolic pathways, an enzyme, adenosine phosphorylase (EC 2.4.2.-), which catalyzed the ribosylation of N6-(Δ2-isopentenyl)adenine,...Full Text Available
The plasma metabolic clearance of biologically active luteinizing hormone (bioactive LH) was studied using the rat interstitial cell testosterone (RICT) bioassay in six hypogonadotropic men after single...Full Text Available
Histamine has been proposed to be an important regulator of energy intake and expenditure. The aim of this study was to evaluate histamine regulation of glucose and lipid metabolism and development...Full Text Available
The purpose of this study was to investigate whether genetically determined properties of muscle metabolism contribute to the exceptional physical endurance of world-class distance runners. ATP, phosphocreatine,...Full Text Available
1 The influence of the nonsteroidal anti-inflammatory drug naproxen on glucose metabolism and on tolbutamide pharmacokinetics and pharmacodynamics has been studied in ten maturity-onset diabetics. 2...Full Text Available
Calcium requirements of North American adolescents were set at 1300 mg/day based on data from white girls. Calcium requirements for Asian-American adolescents have not been studied. Using metabolic...Full Text Available
BackgroundIn vitro data suggest that changes in myocardial substrate metabolism may contribute to impaired myocardial function in diabetic cardiomyopathy (DCM)....Full Text Available
Background and RationaleAtypical antipsychotics exhibit metabolic side effects including diabetes mellitus and obesity. The adverse events are preceded by acute worsening of oral...Full Text Available
The sequential layer-by-layer adsorption of polyanions and polycations to build polyelectrolyte multilayers has triggered enormous interest in their potential uses in a wide range of fields, from photonic to pharmaceutical applications. We show that the conformation of the solvent swollen films - prior to drying - is determined by the initial adsorption conditions, but can be altered ex-situ by exposure to a liquid phase of very high ionic strength. Recently it has been observed that the swelling depends on the charge of the outermost layer. In the PAH/PSS system we saw that assemblies with PSS as the outermost layer swell more than those with PAH outside. A neutron reflectivity study of this effect in addition indicated the existence of two kinds of water, bound with different strength within the films. Beside an unexpected two-step kinetics of swelling, the reflectivity curves of the layers against vacuum before and after ...
Abstract in english We hypothesized that chronic oral administration of the phosphodiesterase-5 inhibitor sildenafil could improve the exercise capacity and pulmonary hemodynamics in patients with pulmonary arterial hypertension (PAH) on the basis of previous short-term studies. We tested this hypothesis in 14 subjects with PAH, including seven patients with the idiopathic form and seven patients with atrial septal defects, but no other congenital heart abnormalities. Patients were subjected (more) to a 6-min walk test and dyspnea was graded according to the Borg scale. Pulmonary flow and pressures were measured by Doppler echocardiography. Patients were given sildenafil, 75 mg orally three times a day, and followed up for 1 year. Sildenafil therapy resulted in the following changes: increase in the 6-min walk distance from a median value of 387 m (range 0 to 484 m) to 462 m (range 408 to 588 m; P
Aims.- To examine the relationships between depression, coronary artery disease, type 2 diabetes, metabolic syndrome and quality of life in Taiwanese adults from a cardiovascular department of a major hospital in Taiwan. Background.- Research suggests associations between depression, metabolic syndrome and quality of life. Despite this fact, few studies have investigated these relationships among Taiwanese. Design.- A cross-sectional descriptive correlational design was used to conduct this study. Methods.- A convenience sample of 140 adults participated in the study. Data were analysed with descriptive statistics, Pearson-s correlations, hierarchical regression and t-tests. Results.- Almost a half of the subjects (465%) had metabolic syndrome. The most common combination of metabolic synd...
... elevated blood sugar levels, but not full-blown diabetes. What are the keys to preventing the disease? ... been well studied, in a study called The Diabetes Prevention Program, in several thousand people with this ...
Phenylketonuria (PKU) is a common genetic disorder in humans that arises from deficient activity of phenylalanine hydroxylase (PAH), which catalyzes the conversion of phenylalanine to tyrosine....Full Text Available
Aromatic Hydrocarbons (PAHs) PAHs, such as benzo(a)pyrene, are commonly found in fuel oils and crude oil, and were detected above LDEQ screening levels for residential soil in...
Homocysteine concentrations are a read-out of methionine metabolism and have been related to changes in lifespan in animal models. In humans, high homocysteine concentrations are an important predictor...Full Text Available
Background: Apheresis is a procedure to selectively obtain blood components. For the collection process citrate is routinely used. It inhibits coagulation by binding to ionized calcium and leads to metabolic alkalosis. Objective: Whether regular apheresis affects bone and mineral metabolism is unknown. The intention of this study was to investigate 1) the acute effects of apheresis on acid-base balance, bone and mineral metabolism and 2) to compare bone mineral density (BMD) at the lumbar spine and hip of donors to matched control subjects. Design: In this open, observational, single-center, cross-sectional study we enrolled 102 regular plasma and thrombocyte donors to pursue objective 1) and compared those to 102 matched controls (CTR) for objective 2). Results: Platelet donation led to s...
In an effort to improve the extrapolation of laboratory data to man and estimate risk of human reproductive toxicity associated with environmental exposure, the pharmacokinetic parameters of the testicular compartment are being studied. Of particular interest is the variety of enzyme systems capable of activating and detoxicating environmental chemicals and drugs. This report compares the metabolism of benzo(a)pyrene by the isolated perfused testis and testicular homogenates in vitro. The cell free in vitro system metabolized benzo(a)pyrene at a much greater rate than the perfused testis and produced a different spectrum of metabolites. Reliable laboratory prediction of biotransformation by the whole organ or intact animal is an essential aspect of reproductive toxicology.
We investigated the association between biomarkers of dermal exposure, naphthyl-keratin adducts (NKA), and urine naphthalene biomarker levels in 105 workers routinely exposed to jet-fuel. A moderate correlation was observed between NKA and urine naphthalene levels (p?=?0.061). The NKA, post-exposure breath naphthalene, and male gender were associated with an increase, while CYP2E1*6 DD and GSTT1-plus (++/+-) genotypes were associated with a decrease in urine naphthalene level (p?0.0001). The NKA show great promise as biomarkers for dermal exposure to naphthalene. Further studies are warranted to characterize the relationship between NKA, other exposure biomarkers, and/or biomarkers of biological effects due to naphthalene and/or PAH exposure. PMID:21961652
This project is concerned with the kinetics and mechanisms of aromatic oxidation and soot and fullerenes formation in flames. The objective of the aromatics oxidation work is to identify and measure the concentration of important intermediates and products in benzene oxidation, and to determine reaction mechanisms and kinetics properties consistent with the behavior seen in flames. The research on soot formation is concerned primarily with the particle inception stages, but the work includes study of soot structure at all stages of growth in order to obtain mechanistic information from evidence of growth steps recorded in the structure of the particles. The ultimate objective is to understand how nascent soot particles are formed from high molecular weight compounds, including the roles of planar and curved PAH and the relationship between soot and fullerenes. The objective of the proposed research on fullerenes is to develop a more ...
Metabolic carbon labelling experiments enable a large amount of extracellular fluxes and intracellular carbon isotope enrichments to be measured. Since the relation between the measured quantities and the unknown intracellular metabolic fluxes is given by bilinear balance equations, flux determination from this data set requires the numerical solution of a nonlinear inverse problem. To this end, a general algorithm for flux estimation from metabolic carbon labelling experiments based on the least squares approach is developed in this contribution and complemented by appropriate tools for statistical analysis. The linearization technique usually applied for the computation of nonlinear confidence regions is shown to be inappropriate in the case of large exchange fluxes. For this reason a sophisticated compactification transformation technique for nonlinear statistical analysis is developed. Statistical analysis is then ...
[F-18]FDG PET brain imaging is an accurate predictor of primary brain tumor grading and prognosis. The purpose of this study was to evaluate simplified [F-18]FDG PET metabolic indices as indicators of proliferative activity of brain tumor cells. Twenty-five patients with glioma were studied with [F-18]FDG PET. From the tissue radioactivity ratios, following tumor metabolic indices were calculated: 1) the tumor-to-whole brain ratio (T/WB), 2) the ratio of tumor-to-contralateral gray matter at the level of centrum semiovale (T/GM), 3) the ratio of tumor-to-contralateral white matter at the level of centrum semiovale (T/WM), 4) the tumor-to-ipsilateral cerebella ratio (T/iCB) and 5) the tumor-to-contralateral cerebellar ratio (T/cCB). A standardized threshold method was used to define ROIs in the tumor areas having representative metabolic activites. Correlations of the tumor ...
A series of radioactive catastrophes (from 1948 to 1967) in the Southern Urals in the USSR led to intensive environmental contamination. Radioactive wastes were dispersed over the 20000 km(2) territory of four provinces-Chelyabinsk, Sverdlovsk, Tyumen' and Kurgan-due to the activity of the military facility that was built in 1948 for the production of nuclear bomb plutonium. The results of 50 years of investigations into the consequences of these disasters allow a general picture of the events that occurred to be reconstructed and allow the medical consequences of the irradiation of about half a million residents to be depicted. However, due to the atmosphere of secrecy and inadequate medical procedures, the results of medical studies of radiation victims are scant. The current protocols present a unique opportunity to study the DNA damage at the nucleotide resolution level in the genome of inhabitants of the given region, who presumably ...
Brain glucose metabolism was evaluated in four patients with acquired immunodeficiency syndrome (AIDS) dementia complex using ["1"8F]fluorodeoxyglucose (FDG) and positron emission tomography (PET) scans at the beginning of therapy with 3'-azido-2',3'-dideoxythymidine (AZT, zidovudine), and later in the course of therapy. In two patients, baseline, large focal cortical abnormalities of glucose utilization were reversed during the course of therapy. In the other two patients, the initial PET study did not reveal pronounced focal alterations, while the post-treatment scans showed markedly increased cortical glucose metabolism. The improved cortical glucose utilization was accompanied in all patients by immunologic and neurologic improvement. PET-FDG studies can detect cortical metabolic abnormalities associated with AIDS dementia complex, and may be used to monitor the ...
A review is presented of the literature through 1977 on the uses of radioactive lead isotopes in metabolicstudies in man, animals, and plants. These studies have been done mainly with the naturally-occurring, long-lived (22-yr half life) "2"1"0Pb, but a few were with 53-hr "2"0"3Pb or 10.6-hr "2"1"2Pb. Such studies have made possible estimates of the metabolic parameters of lead in man and animals, such as intestinal absorption, the ratio of fecal-to-urinary excretion of endogenous lead, residence time of lead in the body and in various organs, and the distribution in the body (skeleton, liver, kidney, and blood). Subsequently, these parameters and data have been used to trace the sources of lead for man, such as those from the atmosphere, food, cigarette smoke, and automobile exhaust.
In vivo plasminogen responses to various stimuli were studied. Plasminogen-125I was prepared and used first for metabolicstudies of plasminogen in control dogs. The average results were:...Full Text Available
To determine a rat strain appropriate for carcinogenicity testing of FYX-051, a xanthine oxidoreductase inhibitor, we performed a 4-week oral toxicity study by administering 0.3, 1 and 3?mg/kg, and 1, 3 and 10?mg/kg of FYX-051 to male Sprague-Dawley (SD) and Fischer (F344) rats, respectively. Histopathology revealed that the degree of FYX-051-induced nephropathy was 3-fold stronger in SD rats than in F344 rats. Our previous study demonstrated that the key factor of species differences in FYX-051-induced nephropathy is purine metabolism. This observation led us to examine the involvement of purine metabolism in differences among two strains of rats. However, purine metabolism was proven not to be implicated as an important factor. Subsequently, other factors responsible for the strain diffe...
The relationship between cigarette smoking and cell damage is complicated, particularly considering the role of oxidative stress. The aim of this study was to identify the relationships among plasma nicotine metabolites, lipophilic antioxidants, and metabolic parameters in smokers and non-smokers. This cross-sectional study recruited 100 subjects who visited the Department of Family Medicine at Kaohsiung Medical University Hospital. Excluding 14 ineligible cases, 46 smokers and 40 non-smokers were enrolled. Plasma nicotine metabolites, lipophilic antioxidants (including retinol, lycopene, a-carotene, b-carotene, d-tocopherol, g-tocopherol and a-tocopherol), related metabolic parameters, and body composition (including height, weight, body mass index, body fat, and waist circumference) were...
The structure of the skin in the epauletted fruit bat (Epomophorus wahlbergi) wing and body trunk was studied with a view to understanding possible adaptations for gas metabolism and...Full Text Available
BackgroundEpidemiological studies have shown a J- or U-shaped relation between alcohol and type 2 diabetes and coronary heart disease (CHD). The underlying mechanisms are not clear....Full Text Available
To investigate the role of thyroxine-binding globulin (TBG) and albumin in the availability of thyroid hormones to peripheral tissues, comprehensive kinetic studies of thyroxine (T4) and triiodothyronine...Full Text Available
Abnormal fat metabolism plays an important role in the pathogenesis of obesity-related type 2 diabetes mellitus. This study examined whether free fatty acid levels (FFAs), like insulin levels, oscillate...Full Text Available
This study was designed to determine the effects of red and far red irradiation on ATP metabolism in etiolated bean buds (Phaseolus vulgaris L. var. Red Kidney). Compared to dark controls,...Full Text Available
IntroductionThe aim of this study was to evaluate the effects of red blood cell (RBC) transfusions on muscle tissue oxygenation, oxygen metabolism and microvascular reactivity in...Full Text Available
Chemical reactions in living cells are under strict enzyme control and conform to a tightly regulated metabolic program. However, uncontrolled and potentially deleterious endogenous reactions occur,...Full Text Available
Benzidine-based azo dyes are proven mutagens and have been linked to bladder cancer. Previous studies have indicated that their initial reduction is the result of the azo reductase activity of the intestinal...Full Text Available
In this study, our main objective was to determine whether energy restriction (ER) affects the rate of oxygen consumption of mice transiently or lastingly and whether metabolic rate plays a role in...Full Text Available
BackgroundHigh serum uric acid concentration (hyperuricemia) has been studied for its relationship with multiple adverse health outcomes, such as metabolic syndrome. Intervention...Full Text Available
Serial studies of iron transport in patients on maintenance dialysis showed normal or raised values in almost all subjects and a transient increase soon after the start of dialysis in three. These...Full Text Available
Calorie restriction (CR) induces a metabolic shift towards mitochondrial respiration; however, molecular mechanisms underlying CR remain unclear. Recent studies suggest that CR-induced mitochondrial...Full Text Available
BackgroundSeven genes involved in folate metabolism are located on chromosome 21. Previous studies have shown that folate deficiency may contribute to mental retardation in Down's...Full Text Available
The continuous addition of toluene as a solute of treated ballast water from oil tankers into a well-defined estuary facilitated the study of the dynamics of dissolved hydrocarbon metabolism in seawater....Full Text Available
BackgroundInterest in lycopene metabolism and regulation is growing rapidly because accumulative studies have suggested an important role for lycopene in human health promotion....Full Text Available
Type 2 diabetes mellitus (DM2) is increasing in incidence, creating worldwide public health concerns and impacting morbidity and mortality rates. An increasing number of studies have demonstrated shared...Full Text Available
This study analyzed the atmospheric emissions produced by the live firing of a 155 mm Howitzer gun. The study was conducted during a live firing training exercise at a Canadian Forces Base. Air emissions were sampled continuously for 3 hours. Particles and chemicals were accumulated on sampling media during the firing of 69 rounds. A single round was fired using 4 bags of propellants, and an additional 3 rounds were fired using 5 bags of propellant. Samples included particulate matter; hydrogen cyanide; polycyclic aromatic hydrocarbons (PAHs); dinitrotoluene compounds; benzene; toluene; ethylbenzene; xylene; metals; aldehydes; nitric acid; nitric oxide; nitrogen dioxide; hydrogen sulphide; and sulphur dioxide. Samples were collected at 8 m to the left of the gun as well as at 22 m in front of the gun muzzle in the line of fire. Results of the study showed that 60 per cent of the particles were below 10 ...
Purpose PR-104, a bioreductive prodrug in clinical trial, is a phosphate ester which is rapidly metabolized to the corresponding alcohol PR-104A. This dinitrobenzamide mustard is activated by reduction to hydroxylamine (PR-104H) and amine (PR-104M) metabolites selectively in hypoxic cells, and also independently of hypoxia by aldo-keto reductase (AKR) 1C3 in some tumors. Here, we evaluate reductive metabolism of PR-104A in mice and its significance for host toxicity. Methods The pharmacokinetics of PR-104, PR-104A and its reduced metabolites were investigated in plasma and tissues of mice (with and without SiHa or H460 tumor xenografts) and effects of potential oxidoreductase inhibitors were evaluated. Results Pharmacokinetic studies identified extensive non-tumor reduction of PR-104A to t...
The winter syndrome in the gilthead sea bream Sparus aurata indicates that the species is exposed to critically low temperatures in Mediterranean aquaculture in winter. The present study of metabolic patterns and molecular stress responses during cold exposure was carried out to investigate this ?disease?, in light of the recent concept of oxygen and capacity limited thermal tolerance. The metabolic profile of fuel oxidation was examined by determining the activities of the enzymes hexokinase (HK), aldolase (Ald), pyruvate kinase (PK), l-lactate dehydrogenase (l-LDH), citrate synthase (CS), malate dehydrogenase (MDH) and 3-hydroxyacyl CoA dehydrogenase (HOAD) in heart, red and white muscle after exposure to temperatures of 10, 14 and 18?C. Especially, the increase in LDH activity combined ...
Diethylene glycol (DEG) is an industrial chemical, the misuse of which has led to numerous epidemic poisonings worldwide. The mechanism of its toxicity has not been defined as to the precise relationship between the metabolism of DEG and target organ toxicity. The purpose of this study was to investigate the mechanism for the acute toxicity of DEG, and the effect of the alcohol dehydrogenase inhibitor 4-methylpyrazole (fomepizole), by determining the relationship between accumulation of DEG or its metabolites and the resulting kidney and liver toxicity. Rats were treated by oral gavage with water, 2 g/kg DEG (low dose), 10 g/kg DEG (high dose), or 10 g/kg DEG + fomepizole, and blood and urine were collected over 48 h. Rats treated with high-dose DEG had metabolic acidosis, increased BUN an...
Adipose tissue plays an essential role in energy homeostasis as a metabolic and endocrine organ. Accordingly, adipocytes are emerging as a major drug target for obesity and obesity-mediated metabolic syndrome. Dysfunction of enlarged adipocytes in obesity is involved in obesity-mediated metabolic syndrome. Adipocytokines, such as adiponectin released from small adipocytes, are able to prevent these disorders. In this study, we found that honokiol, an ingredient of Magnolia officinalis used in traditional Chinese and Japanese medicines, enhanced adipocyte differentiation in 3T3-L1 preadipocytes. Oil Red O staining showed that treatment with honokiol in the presence of insulin dose-dependently increased lipid accumulation in 3T3-L1 preadipoyctes although its activity was weak compared with r...
The present study was designed to determine the exercise intensity equivalent to the metabolic aerobic/anaerobic transition of alloxan diabetic rats, through lactate minimum test (LMT), and to evaluate the effects of swimming exercise at this intensity (LM) on the glucose and protein metabolism of these animals. Adult male Wistar rats received alloxan (SD, alloxan-injected rats that remained sedentary) intravenously (30 mg kg?1 body weight) for diabetes induction. As controls (SC, vehicle-injected rats that remained sedentary), vehicle-injected rats were utilized. Two weeks later, the animals were submitted to oral glucose tolerance test (oGTT) and LMT. After the tests, some of the animals were submitted to swimming exercise training [TC (vehicle-injected rats that performed a 6-week exerc...
Abstract Background- Cyclosporine is used for treatment of transplanted patients and for immune-mediated diseases. Cyclosporine is known to cause a combination of metabolic side effects including hypertension, hyperkalemia, hypercalciuria and hypomagnesemia. These side effects except for hypomagnesemia are the cardinal features of familial hyperkalemia and hypertension (FHHt), also called pseudohypoaldosteronism type II (PHA II). FHHt is caused by mutations in the kinases WNK1 and WNK4 resulting in an increase in renal Na-Cl cotransporter (NCC) apical distribution and function. Therefore, we studied whether cyclosporine-s metabolic side effects are mediated by WNK4 and NCC. Design- Sprague-Dawley (SD) rats were treated by cyclosporine 25-mg-kg-1 subcutaneously for 14-days. Blood pressure, ...
A new method is being developed to quickly screen for the human exposure potential to polycyclic aromatic hydrocarbons (PAHs) and organochlorines (OCs). The development involves two key elements: identifying suitable signals that represent intracellular changes that are specific to PAH and OC exposure, and constructing a device to guide the biological cell growth so that signals from individual cells are consistent and reproducible. We are completing the identification of suitable signals by using synchrotron radiation-based (SR) Fourier-transform infrared (FTIR) spectromicroscopy in the mid-infrared region (4000-400 cm-1). Distinct changes have been observed in the IR spectra after treatment of human cells in culture medium with PAHs and OCs. The potential use of this method for detecting exposure to PAHs and OCs has been tested and compared to a reverse transcription polymerase chain reaction (RT-PCR) ...
Desorption behavior of pyrene, phenanthrene and naphthalene from fullerene, single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) was examined. Available adsorption space of carbon nanotubes (CNTs) was found to be the cylindrical external surface, neither the inner cavities nor inter-wall spaces due to impurities in the CNTs and restricted spaces (0.335 nm) of the MWCNTs, respectively. Desorption hysteresis was observed for fullerene but not for CNTs. Deformation-rearrangement was proposed to explain the hysteresis of polycyclic aromatic hydrocarbons (PAHs) for fullerene, due to the formation of closed interstitial spaces in spherical fullerene aggregates. However, long, cylindrical carbon nanotubes could not form such closed interstitial spaces in their aggregates due to their length, thus showing no significant hysteresis. High adsorption capacity and reversible adsorption of PAHs on CNTs imply the potential ...
Positron emission tomography (PET) and X-ray computed tomography (CT) performed with PET/CT cameras allow us to obtain concurrently information on the presence and degree of alterations of myocardial perfusion and metabolism and on coronary arteries calcification. Furthermore, by gated myocardial perfusion studies, PET may provide crucial information on regional coronary blood flow reserve and endothelial dysfunction. A number of recent papers provide some insight on the potential of PET/CT in cardiology and in the assessment of various cardiovascular diseases including various types of vasculitis and metabolic diseases.
Biosorption is an important removal mechanism in treating hydrophobic toxic organics in biological reactors. Equilibrium sorption isotherms and sorption kinetics of 2,4-dichlorophenol on live and chemically inactive anaerobic granules were studied. A metabolic inhibitor was used to inactivate the biological activity of the biomass. Results showed that the difference in the biosorption of live and chemically inactive anaerobic granules is not significant. This would suggest that anaerobic biosorption is mainly a physical-chemical process and that metabolic-mediated diffusion in the process is negligible. 12 refs., 3 tabs., 7 figs.
The in vivo toxic effects of hexavalent chromium (20 mg/liter) on hemolymph glucose, tissue glycogen, total free sugars, and active and total phosphorylases of an edible, freshwater crab Barytelphusa guerini were studied. In a 15-day exposure span followed by a 15-day postexposure recovery, the time-course alterations in these constituent segments of the glycogen metabolism indicate an inconsistent depletion in metabolite levels and elevated enzyme activities during exposure period as well as hyperglycemia. An insignificant recovery was observed in these parameters on the 15th day of the postexposure phase.
The effect of protein malnutrition on the metabolism of collagen in bone was studied in young female albino rats after a single injection of "3H-proline. Both specific and total radioactivities of hydroxyproline in the total collagen of the bone were found to decrease in the protein-deficient animals, indicating decreased rate of collagen synthesis. In the urine the amount of hydroxyproline excreted and total radioactivity of "3H-hydroxyproline were greatly decreased. The results of the present investigation therefore clearly indicate decreased synthesis and catabolism of collagen in bones of protein deficient animals compared to controls. (auth.).
This paper discussed the potential of biofuels with particular reference to the situation in Germany and Europe. Emphasis was on technical potential, such as biofuel production, utilization and environmental aspects. The Institute of Agricultural Technology and Biosystems Engineering ran vTI emission tests on diesel engines to evaluate the environmental impacts of biofuels. This testing facility is able to drive heavy-duty diesel engines in both stationary and dynamic test cycles, such as the European ESC and ETC. Additional analyses were conducted to determine the fine and ultra-fine particles, polycyclic aromatic hydrocarbons (PAH), aldehydes, ketones, and the usual regulated exhaust gas compounds. Ames tests were conducted to assess the mutagenic potential of tailpipe emissions. Previous study results showed that neat vegetable oils can render the exhaust high in mutagenic potency. Some of the non-regulated exhaust gas compounds were found ...
Translating experimental findings into clinically effective therapies is one of the major bottlenecks of modern medicine. As this has been particularly true for cerebrovascular research, attention has turned to the quality and validity of experimental cerebrovascular studies. We set out to assess the study design, statistical analyses, and reporting of cerebrovascular research. We assessed all original articles published in the Journal of Cerebral Blood Flow and Metabolism during the year 2008 against a checklist designed to capture the key attributes relating to study design, statistical analyses, and reporting. A total of 156 original publications were included (animal, in vitro, human). Few studies reported a primary research hypothesis, statement of purpose, or measures to safeguard in...
Metabolism of benzene is thought to be necessary to produce the toxic effects, including carcinogenicity, associated with benzene exposure. To extrapolate from the results of rodent studies to potential health risks in man, one must know how benzene metabolism is affected by species, dose, dose rate, and repeated versus single exposures. The purpose of our studies was to determine the effect of repeated inhalation exposures on the metabolism of [14C]benzene by rodents. Benzene metabolism was assessed by characterizing and quantitating urinary metabolites, and by quantitating 14C bound to hemoglobin and micronuclei induction. F344/N rats and B6C3F1 mice were exposed, nose-only, to 600 ppm benzene or to air (control) for 6 hr/day, 5 days/week for 3 weeks. On the last day, both benzene-pretreated and control animals were exposed to 600 ppm, 14C-labeled benzene for ...
To elucidate biosorption mechanism and removal efficiency of plant residues as a biosorbent to abate polycyclic aromatic hydrocarbons (PAHs) in wastewater, sorption of PAHs onto wood chips (WC), ryegrass roots (RR), orange peels (OP), bamboo leaves (BL), and pine needles (PN) were investigated. The structural characterization of the biosorbents was analyzed by elemental composition, BET-N2 surface area, and Fourier transform infrared spectroscopy. PAHs sorption to the selected biosorbents were compared and correlated with their structures. Biosorption isotherms fit well with Freundlich equation and the mechanism was dominated by partition process. The magnitude of phenanthrene partition coefficients (Kd) followed the order of PN>BL>OP>RR>WC, ranged from 2484+/-24.24 to 5306+/-92.49L/kg. Ex...
The contents of polycyclic aromatic hydrocarbons (PAH) and phenolic substances in Frankfurter-type sausages were investigated depending on hot smoking conditions (glow smoke). For the 24 smoking experiments (performed in duplicates) three different smoke densities and ventilator velocities as well as wood chips with five different moisture contents were tested. During the smoking process, concentrations of O"2, CO"2 and CO, humidity and temperature in the smoking chamber as well as smoke generation temperature were determined. The chemical analysis included the contents of the 15+1 EU priority PAH and the phenolic substances guaiacol, 4-methylguaiacol, syringol, eugenol and trans-isoeugenol. The smoking conditions had a significant influence on smoke generation temperature, organoleptic pr...
The individual contributions in these proceedings are indexed separately. Main topics covered include the measurement of biological nitrogen fixation, studies of soil organic matter, investigations of nutrient uptake and use by plants, studies of plant metabolism and new methodologies in the analysis of stable isotopes. Refs, figs and tabs.
This bibliographical study compiles and analyzes findings about the metabolism and resorption of molybdenum. Besides including studies on the physiology of molybdenum 99, a general survey is given on molybdenum in the environment and on its physiological behaviour. In particular, information on the dependence of molybdenum resorption on various factors, such as the chemical form, antagonisms etc., are gathered from literature. These factors have to be considered for sensibly carrying out necessary experiments.
Pathways of salicylic acid (SA) biosynthesis and metabolism in tobacco have been recently identified. SA, an endogenous regulator of disease resistance, is a product of phenylpropanoid metabolism formed...Full Text Available
BACKGROUNDLifestyle modifications are successfully employed to treat obese and overweight women with polycystic ovary syndrome (PCOS). The aims of the current pilot study were (i) to compare the efficacy on reproductive functions of a structured exercise training (SET) programme with a diet programme in obese PCOS patients and (ii) to study their clinical, hormonal and metabolic effects to elucidate potentially different mechanisms of action.METHODSForty obese PCOS patients with anovulatory infertility underwent a SET programme (SET group, n = 20) and a hypocaloric hyperproteic diet (diet group, n = 20). Clinical, hormonal and metabolic data were assessed at baseline, and at 12- and 24-week follow-ups. Primary endpoint was cumulative pregnancy rate.RESULTSThe two groups had similar demogra...
Within the past decade two important groups of radiopharmaceuticals labelled with /sup 123/I were introduced into the clinical application opening new areas of metabolicstudies in nuclear medicine: radioiodinated fatty acids were developed for metabolicstudies of the myocardium and radioiodinated amphetamine derivatives were prepared for studying brain diseases by means of SPECT. It must be emphasized that the radiochemical problems with both groups of compounds are practically the same since both are radioiodinated by a nucleophilic substitution mechanism using /sup 123/I directly in its anionic form. The clinical application of brain imaging agents, particularly the one of p-/sup 123/I-iodo-N-isopropylamphetamine, is important and will presumably increase as soon as the details of the individual biochemical steps, which are involved in brain uptake mechanisms, are evaluated. It ...
and streambed sediment samples 2-6. Graphs showing: 2. Cesium-137 profile in HOE core 3. PAH trends in Lake Houston cores 4. DDE trends in Lake Houston cores 5. Trends in six trace...
Lab scale mulch biofilm barriers were constructed and tested to evaluate their performance for preventing the migration of aqueous and surfactant solubilized PAHs. The spatial distribution of viable PAH degrader populations and resultant biofilm formation were also monitored to evaluate the performance of the biobarrier and the prolonged surfactant effect on the PAH degrading microorganism consortia in the biobarrier. Sorption and biodegradation of PAHs resulted in stable operation of the system for dissolved phenanthrene and pyrene during 150 days of experimentation. The nonionic surfactant could increase the solubility of phenanthrene and pyrene significantly. However, the biobarrier itself couldn't totally prevent the migration of micellar solubilized phenanthrene and pyrene. The presence of surfactant and the resultant highly increased phenanthrene or pyrene concentration didn't appear to cause ...
This work is directly to analysis of atmosphere surrounding Ipiranga Refinery; witch is located in the city of Rio Grande, in estate of Rio Grande do Sul. The refinery is surrounded by neighborhood, witch are impacted by atmospheric emissions of refinery. The objective of this work is correlating the refinery to the inhabitants that lives near the refinery, using an environmental sustainability index. This work will be achieve by analysis of Polycyclic Aromatic Hydrocarbons (PAH) bounded in particulate matter with diameter of 100 {mu}m (PTS), the acquisition of health data on the city hospitals and correlation of this data with PAH concentrations in Particulate Matter. The Samples were obtain by FEPAM, witch have three samples sites in the center of city. The samples was obtained by a High Volume Sampler equipped with quartz fiber filters. The meteorological data important to this work, like wind direction and speed, will be obtain in ...
Abstract Aims: The aim of this study was to examine whether metabolic syndrome (MS) is associated with periodontitis in a representative sample of Korean adults, who were involved in the Fourth Korea National Health and Nutrition Examination Survey (KNHANES). Materials and Methods: A total of 7178 subjects over the age of 19 years who participated in KNHANES were examined. MS was defined as the definition proposed by the National Cholesterol Education Program Adult Treatment Panel III and the abdominal obesity cut-off line based on Korean Society for the Study of Obesity. The periodontal status was assessed by the Community Periodontal Index. Multivariate logistic regression analysis was carried out adjusting for the sociodemographics, oral health behaviours and status, and health behaviou...
In patients subjected to bone marrow transplantation the aggressive measures necessarily preceding this treatment lead to drastic metabolic changes which, in turn, are a cause of marked disturbances of homeostasis. The general preparatory measures in the form of cytoreduction by cytostatic drugs are broadened for leukaemic patients to include wholebody irradiation. During the study described here investigations were carried out into the resulting strain on the metabolism. One of the most essential changes observed in those patients was a nitrogen loss of up to approx. 20 g/day that occurred during the immunosuppressive phase. This was accompanied by markedly pronounced variations in fluid elimination, which partly were of an iatrogenic nature. An immediate and sufficient substitution of amino acids in connection with complete parenteral nutrition rapidly acted to compensate for the nitrogen losses, even though these could ...
Sustained metabolic rates (SusMR) are time-averaged metabolic rates that are measured in free-ranging animals maintaining constant body mass over periods long enough that metabolism is fueled by food...Full Text Available
The lung has the potential of metabolizing many foreign chemicals to a vast array of metabolites with different pharmacological and toxicological properties. Because many chemicals require metabolic...Full Text Available
Estrogen metabolism is suggested to play an important role in estrogen-induced breast carcinogenesis. Epidemiologic studies suggest that diets rich in phytoestrogens are associated with a reduced risk of breast cancer. Phytoestrogens are biologically active plant compounds that structurally mimic 17b-estradiol (E2). We hypothesize that phytoestrogens, may provide protection against breast carcinogenesis by altering the expression of estrogen-metabolizing enzymes cytochrome P450 1A1 (Cyp1A1) and 1B1 (Cyp1B1). Cyp1A1 and Cyp1B1 are responsible for the metabolism of E2 to generate 2-hydroxyestradiol (2-OHE2) and 4-hydroxyestradiol (4-OHE2), respectively. Studies suggest that 2-OHE2 and 2-methoxyestradiol may protect against breast carcinogenesis, while 4-OHE2 is carcinogenic in rodent models....
1. Gamma globulin metabolism and distribution were studied employing rabbit gamma globulin (RGG)I(131) 24 times in 13 control rabbits. Similar studies were performed before and during the ananmestic response in 4 rabbits previously sensitized with a polyvalent pneumococcal vaccine. 2. During the ananmestic response, gamma-globulin levels increased from 1.0 to 6.0 gm/100 ml, and the gamma-globulin pool increased from 0.7 to 4.7 gm/kg. There was no change in the intravascular-extravascular partition of gamma globulin. 3. Gamma globulin degradation increased from 0.06 to 0.33 gm/kg/day during the 28 days of the immunization period while gamma globulin synthesis increased even further to average 0.47 gm/kg/day. Following the attainment of elevated gamma globulin levels the fractional rate of RGG-I(131) turnover increased from 8.0 to 12.5 per cent/day. 4. No differences were noted in the metabolism of ...
A Quantitative Computed Tomography (QCT) method, simplifying the well-known technique proposed by Genant (1982) and applied to a standard third generation whole body CT scanner is described. This technique was applied in the measurement of the trabecular bone which has high sensitivity for metabolic changes. The BMC (Bone Mineral Content) measured in different groups of subjects (healthy postmenopausal patients versus women with postmenopausal osteoporosis) showed a highly significant difference (p<0.001). The precision of repositioning (coefficient of variation 1.8% to 2.3%, obtained in healty male patients) and the good, linear relationship computed from the phantom values, minimize measurement errors. Since this method is quickly applied and involves low-dose radiation-exposure, it could be introduced in the clinical study of metabolic bone diseases.
The effect of sugar on plant metabolism, which is known to be similar to hormone-like signaling, was metabolomically studied using Melissa officinalis (lemon balm). The metabolite profiles of M. officinalis treated with sucrose were analyzed by gas chromatography-mass spectrometry (GC-MS) and principal component analysis (PCA). A total of 64 metabolites from various chemical classes including alcohols, amines, amino acids, fatty acids, inorganic acids, organic acids, phosphates, and sugars were identified by GC-MS. Three groups treated with different sucrose concentrations were clearly separated by PCA of their metabolite profiles, indicating changes in the levels of many metabolites depending on the sucrose concentration. Metabolite profiling revealed that treatment with a higher sucrose ...
The present study was designed with an aim to analyze the effect of acute aluminium phosphide (ALP) exposure (10mg/kg b.wt, intragastrically) on the kinetic characteristics of cytochrome oxidase and energy metabolism in male Wistar rat liver mitochondria. Liver mitochondrial preparations from ALP-treated rats exhibited significant decrease (66%) in the activity of cytochrome oxidase suggesting that there was a decrease in the catalytic efficiency of the active oxidase molecules on ALP treatment. The decreased activity of cytochrome oxidase with altered NADH and succinic dehydrogenase activities might have contributed towards a significant decline in state 3 and state 4 respiration as observed. These alterations in the electron transport chain complexes in turn adversely affected the ATP sy...
Young children are at increased risk for valproic acid (VPA) hepatotoxicity. Urinary organic acid profiles, as a surrogate of mitochondrial function, were obtained in children 1.9 to 17.3 years of age (n = 52) who were undergoing treatment with VPA for seizure disorders. Age-matched patients receiving treatment with carbamazepine (CBZ; n = 50) and healthy children not undergoing treatment (n = 22) served as controls. Age-related changes in organic acid profiles were observed in all three groups. Although the untreated and CBZ control groups were indistinguishable from each other with respect to the principal-component analysis (PCA) score plots of the subjects, a distinct boundary was apparent between the VPA and each of the control groups. Interindividual variability was observed in the V...
The relationships between changes in energy metabolism and the antioxidant defense system in the weed species Ipomoea triloba L. during seed germination and early seedling growth were investigated. The effects of some common allelochemicals on these parameters also were studied. Respiratory activity and the activities of alcohol dehydrogenase, superoxide dismutase, catalase, guaicol peroxidase, ascorbate peroxidase, glutathione reductase, and lipoxygenase were measured. Mitochondrial oxidative phosphorylation resumed shortly after the seed imbibition period, as indicated by considerable KCN-sensitive respiratory activity in embryos of I. triloba. The occurrence of superoxide dismutase, catalase, guaicol peroxidase, and lipoxygenase activities in the embryos, along with significant KCN-inse...
T-2 toxin, a highly toxic member of the type-A trichothecenes, is produced by various Fusarium moulds that can potentially affect human health. It is strongly cytotoxic for human hematopoietic progenitors. Alimentary toxic aleukia (ATA), a disease typically associated with human, is primarily induced by T-2 toxin. A comparison of the metabolism of T-2 toxin incubated with hepatocytes of rats, piglets, chickens, and the hepatic subcellular fractions (microsomes and cytosol) of piglets, chickens, rats, and carp (common carp and grass carp) was carried out. The activities of the recombinant pig CYP3A29 on the transformation of T-2 and HT-2 toxins were preliminary studied. Metabolites were identified by novel LC/MS-IT-TOF. Qualitative similarities and differences across the species were observ...
Allyl acetate (AAC), allyl alcohol (AAL), and acrolein (ACR) are used in the manufacture of detergents, plastics, pharmaceuticals, and chemicals and as agricultural agents. A metabolic relationship exists between these chemicals in which allyl acetate is metabolized to allyl alcohol and subsequently to the highly reactive, a,b-unsaturated aldehyde, acrolein. Due to the weaker reactivity of the protoxicants, allyl acetate and allyl alcohol, relative to acrolien we hypothesized the protoxicants would attain greater systemic exposure and therefore deliver higher doses of acrolein to the internal organs. By extension, the higher systemic exposure to acrolein we hypothesized should lead to more internal organ toxicity in the allyl acetate and allyl alcohol treated animals relative to those trea...
Recent studies indicate that [Fe]-hydrogenases and H{sub 2} metabolism are widely distributed among green algae. The enzymes are simple structured and catalyze H{sub 2} evolution with similar rates than the more complex [Fe]-hydrogenases from bacteria. Different green algal species developed diverse strategies to survive under sulfur deprivation. Chlamydomonas reinhardtii evolves large quantities of hydrogen gas in the absence of sulfur. In a sealed culture of C. reinhardtii, the photosynthetic O{sub 2} evolution rate drops below the rate of respiratory O{sub 2} consumption due to a reversible inhibition of photosystem II, thus leading to an intracellular anaerobiosis. The algal cells survive under these anaerobic conditions by switching their metabolism to a kind of photo-fermentation. Although possessing a functional [Fe]-hydrogenase gene, the cells of Scenedesmus obliquus produce no significant amounts of H{sub 2} under ...
Studies of ribulose-1,5-bisphosphate (RuBP) carboxylase from taxonomically diverse plants show that the enzyme from C3 and crassulacean acid metabolism pathway species exhibits lower Km(CO2)...Full Text Available
In this study, bone mineral density (BMD) of normal (CON), ovariectomized (OVX) and partially nephrectomized (NFR) rats was measured by 31P NMR spectroscopy; bone matrix density was...Full Text Available
Peroxisome proliferator activated receptor-{gamma} (PPAR{gamma}) regulates metabolic homeostasis and adipocyte differentiation, and it is activated by oxidized and nitrated fatty acids. Here we report the crystal structure of the PPAR{gamma} ligand binding domain bound to nitrated linoleic acid, a potent endogenous ligand of PPAR{gamma}. Structural and functional studies of receptor-ligand interactions reveal the molecular basis of PPAR{gamma} discrimination of various naturally occurring fatty acid derivatives.
Kernels of Zea mays on an intact plant accumulate indole-3-acetic acid (IAA) at the rate of 190 ng g-1 fresh weight h-1. Of the IAA synthesized, 97% is in the esterified form and less than 3% remains...Full Text Available
We studied how the introduction of an additional ATP-consuming reaction affects the metabolic fluxes in Lactococcus lactis. Genes encoding the hydrolytic part of the F1 domain...Full Text Available
Previous studies demonstrated that perinatal exposure to polybrominated diphenyl ethers (PBDEs), a major class of brominated flame retardants, may affect thyroid hormone (TH) concentrations by inducing...Full Text Available
This study investigated the effects of electromagnetic fields on enzymes involved in purine metabolism in human peripheral blood mononuclear cells in vitro. Cells were obtained from 20 volunteers. We...Full Text Available
There are few studies that focused on the prognostic value of FDG-PET on small cell lung cancer (SCLC). Not only FDG uptake (maxSUV), but also metabolic size (greatest dimension of PET positive mass) may determine the prognosis of SCLC. Here, we investigated the prognostic significance of maxSUV, and the metabolic size in SCLC patients. Biopsy-proven SCLC patients (n=21; age, means.d.=67.39y; male: female=19: 3) who had underwent FDG-PET within 4 weeks of chemotherapy initiation were enrolled. There were 7 extensive disease (ED) and 14 limited disease (LD) patients. The maxSUV and the metabolic size were measured, and then, size-incorporated maxSUV (SIMaxSUV = maxSUV x metabolic size) were calculated at individual SCLC masses. SIMaxSUV of main lesion (main-SIMaxSUV), and the summed value of SIMaxSUV of all PET positive masses (summed-SIMaxSUV) were obtained. In addition, age, stage, ...
Possible use of stable radioisotopes in studies on nutrition and medicine problems that may be used in investigations of babies, children, pregnant women is shown. Attention is paid to behaviour of limited number of elements: hydrogen, carbon, nitrogen, oxygen. The IAEA plans implementation of a new coordinated research program on use of stable isotopes for studying nutrition problems and related diseases. The program emphasis will be placed on protein metabolism measurements and estimation of energy consumption in control population groups in developing countries.
PAH biomineralization measurements of yardwaste compost samples indicated heterogeneous distribution of active microorganisms and substantial sequestration of the non-polar substrate in the compost matrix. - The purpose of the study was to evaluate the potential of phenanthrene and fluoranthene biodegradation in yardwaste compost materials. These polynuclear aromatic hydrocarbons were chosen for this work because they are relatively readily biodegradable and ubiquitous in the environment. Compost samples were incubated in biometers with "1"4C-labeled phenanthrene and the evolution of "1"4CO_2 was assessed as a measure of mineralization. The "1"4CO_2 evolution varied widely among replicate biometers, possibly as the result of (1) uneven and patchy colonization of phenanthrene-degrading microorganisms on compost particles, and (2) non-uniform dispersion of the labeled substrate spike into the yardwaste microenvironment. Mineralization of ...
Organic materials released from energy-related activities could affect human health and the environment. To better assess possible impacts, we developed a model to predict the fate of spills or discharges of pollutants into flowing or static bodies of fresh water. A computer code, Aquatic Pathways Model (APM), was written to implement the model. The computer programs use compartmental analysis to simulate aquatic ecosystems. The APM estimates the concentrations of chemicals in fish tissue, water and sediment, and is therefore useful for assessing exposure to humans through aquatic pathways. The APM will consider any aquatic pathway for which the user has transport data. Additionally, APM will estimate transport rates from physical and chemical properties of chemicals between several key compartments. The major pathways considered are biodegradation, fish and sediment uptake, photolysis, and evaporation. The model has been implemented with parameters for distribution of phenols, an ...
Sediment trap fluxes of solids, organic carbon, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) were measured in Lake Superior in 1984 and 1985. Mass fluxes from surface waters ranged from 0.14 to 1.1 g/m{sup 2}{center dot}day and increased near the lake floor due to resuspension of surficial sediment and horizontal transport in the benthic nepheloid layer. Organic matter fluxes from surface water ranged from 60 to 90 mg of C/m{sup 2}{center dot}day, with {approximately}5% of organic carbon settling from surface waters accumulating in bottom sediments. Concentrations of PCBs and PAHs are enriched 10-100 times on settling particles relative to those on suspended particles. Resultant settling fluxes are 10-100 times greater for several PCB and PAH compounds than net accumulation rates in bottom sediments, indicating the effective and rapid recycling in the benthic region. Biological packaging of ...
We present new low resolution Spitzer mid-infrared spectroscopy of a sample of 20 ROSAT selected local Narrow Line Seyfert 1 galaxies (NLS1s). We detect strong AGN continuum in all and clear PAH emission in 70% of the sources. The 6.2 micron PAH luminosity spans three orders of magnitudes, from ~10^(39) erg/s to ~10^(42) erg/s providing strong evidence for intense ongoing star formation in the circumnuclear regions of these sources. Using the IRS/Spitzer archive we gather a large number of additional NLS1s and their broad line counterparts (BLS1s) and constructed NLS1 and BLS1 sub-samples to compare them in various ways. The comparison shows a clear separation according to FWHM(H_beta) such that objects with narrower broad H_beta lines are the strongest PAH emitters. We test this division in various ways trying to remove biases due to luminosity and aperture size. Specifically, we find that star formation activity around ...
Rats or mice acutely exposed to high concentrations of ozone show an immediate and significant weight loss, even when allowed free access to food and water. The mechanisms underlying this systemic response to ozone have not been previously elucidated. We have applied the technique of global gene expression analysis to the livers of C57BL mice acutely exposed to ozone. Mice lost up to 14% of their original body weight, with a 42% decrease in total food consumption. We previously had found significant up-regulation of genes encoding proliferative enzymes, proteins related to acute phase reactions and cytoskeletal functions, and other biomarkers of a cachexia-like inflammatory state in lungs of mice exposed to ozone. These results are consistent with a general up-regulation of different gene families responsive to NF-#kappa#B in the lungs of the exposed mice. In the present study, we observed significant down-regulation of different families of mRNAs in the livers of ...
Colorectal cancer is the third most common malignant tumor and the fourth-leading cause of cancer death worldwide. The crucial role of fatty acids for a number of important biological processes suggests a more in depth analysis of inter-individual differences in fatty acid metabolizing genes as contributing factor to colon carcinogenesis. We examined the association between genetic variability in 43 fatty acid metabolism-related genes and colorectal risk in 1225 CRC cases and 2032 controls participating in the European Prospective Investigation into Cancer and Nutrition study. 392 single nucleotide polymorphisms were selected using pairwise tagging with an r(2) cutoff of 0.8 and a minor allele frequency of >5%. Conditional logistic regression models were used to estimate odds ratios and corresponding 95% confidence intervals. Haplotype analysis was performed using a generalized linear model framework. On the genotype ...
Investigated here were the effects of microwave (MW) radiation (2450-MHz, continuous-wave, mean specific absorption rate of 103.5 + or - 4.2 W/kg) and convention heating on the nonphosphorylating oxidative metabolism of human peripheral mononuclear leukocytes (96% lymphocytes, 4% monocytes) at 37 C. Metabolic activity, determined by chemiluminescence (CL) of cells challenged with luminol (5-aminO-2, 3-dihydro-1, 4-phthalazinedione) linked to bovine serum albumin, was detected with a brightness photomer. A significant stimulation after after MW exposure (p < 0.005) over total CL of matched 37 C-incubator controls was observed. A similar degree of stimulation, compared to incubator controls, was also detected after sham treatment. No significant difference existed between changes in total CL or stimulation indices of the MW and sham-exposed groups. Exposure to MW radiation, under normothermic (37 + or - 0.03 C) conditions, appears to have no ...
Insulin receptors on the surface of isolated rat adipocytes were photoaffinity labeled at 12 degrees C with the iodinated photoreactive insulin analogue, 125I-B2 (2-nitro-4-azidophenylacetyl)-des-PheB1-insulin, and the pathways in the intracellular processing of the labeled receptors were studied at 37 degrees C. During 37 degrees C incubations, the labeled 440-kDa insulin receptors were continuously internalized (as assessed by trypsin inaccessibility) and degraded such that up to 50% of the initially labeled receptors were lost by 120 min. Metabolic poisons (0.125-0.75 mM 2,4-dinitrophenol (DNP) and 1-10 mM NaF), which led to dose-dependent depletion of adipocyte ATP pools, inhibited receptor loss, and caused up to 3-fold increase in intracellular receptor accumulation. This effect was due to inhibition of intracellular receptor degradation, and there was no apparent effect of the metabolic poisons on initial ...
AMP-activated-protein-kinase (AMPK) is a key sensor and regulator of cellular and whole-body energy metabolism and plays a key role in regulation of lipid metabolism. Since lipid metabolism...Full Text Available
13C metabolic flux analysis (MFA) is the most comprehensive means of characterizing cellular metabolic states. Uniquely labeled isotopic tracers enable more focused analyses to probe...Full Text Available
BackgroundMicroorganisms display vast diversity, and each one has its own set of genes, cell components and metabolic reactions. To assess their huge unexploited metabolic potential...Full Text Available
Heavy metals discharged from industries are a major source of pollution which has become a threat to all forms of life. Among the various heavy metals, cadmium is known to be highly toxic even in low concentrations. The harmful effects of cadmium is attributed to its effects on sulfhydryl groups of enzymes, especially dehydrogenases. Various aspects of cadmium pollution on fishes have been extensively reviewed. A survey of the literature reveals that few attempts have been made to study the various aspects of cadmium toxicity in crustaceans and these studies were mainly devoted to marine forms. The freshwater crustaceans, particularly the freshwater field crab, Barytelphusa guerini, has received little attention. The present study reports the influence of cadmium on certain aspects of protein metabolism in the tissues of a freshwater field crab, Barytelphusa guerini, and important component of the paddy ...
Cadmium is a toxic, non-essential heavy metal inhibiting numerous enzymes with functional sulfhydryl groups. Among the animals, aquatic organisms are most sensitive to heavy metals. Various aspects of toxic effects of cadmium pollution on fishes have been extensively reviewed. Survey of literature reveals that relatively few attempts have been made on the various aspects of cadmium toxicity in crustaceans and these studies were mainly devoted to marine forms. The freshwater crustaceans, particularly the freshwater field crab, Barytelphusa guerini, received less attention. This crab forms one of the major components of the paddy field ecosystem and has an edible importance among local populations. Apart from this, these crabs are easily available, maintainable in the laboratory and data obtained in this study can be extrapolated to other crustaceans. The present study reports the influence of cadmium on certain aspects of ...
The lipid composition of skin is important to a variety of functions served by this organ. Therefore, skin expresses multiple enzymes that synthesize and metabolize lipids. An important class of lipid...Full Text Available
The importance of cancer metabolism has been appreciated for many years, but the intricacies of how metabolic pathways interconnect with oncogenic signaling are not fully understood. With a clear understanding...Full Text Available
Emerging evidence indicates that impaired cellular energy metabolism is the defining characteristic of nearly all cancers regardless of cellular or tissue origin. In contrast to normal cells, which...Full Text Available
The promising use of mesenchymal stromal cells (MSC) in regenerative technologies accounts for necessity of detailed study of their physiology. Proliferation and differentiation of multipotent cells often involve changes in their metabolic state. In the present study, we analyzed the expression of ATP-sensitive potassium (K"A"T"P) channels in MSC and upon in vitro differentiation. K"A"T"P channels are present in many cells and regulate a variety of cellular functions by coupling cell metabolism with membrane potential. Kir6.1, Kir6.2 and SUR2A were expressed in undifferentiated MSC, whereas SUR2B and SUR1 were not detected on cDNA and protein level. Upon adipogenic differentiation Kir6.1 and SUR2A showed a significant reduction of the amount of mRNA by 84% and 95%, respectively, whereas Ki...
This case report makes evident that in a 75 years old patient with a (cured) femoral neck fracture 15 years ago a refracture at the same site following a new trauma could not be detected by conventional X-ray. The follow-up of a radionuclide bone study, however, enabled the dignosis of a refracture. From these findings, it is further evident that the decreased bone metabolism in older patients has to be considered. Thus, although the initial bone scan following the trauma is negative, a follow-up scan should be performed within a 4 day-period.
This case report makes evident that in a 75 years old patient with a (cured) femoral neck fracture 15 years ago a refracture at the same site following a new trauma could not be detected by conventional X-ray. The follow-up of a radionuclide bone study, however, enabled the dignosis of a refracture. From these findings, it is further evident that the decreased bone metabolism in older patients has to be considered. Thus, although the initial bone scan following the trauma is negative, a follow-up scan should be performed within a 4 day-period. (orig.).
Iodine deficiency disorders (IDD) are one of most common nutritional deficiencies in the world. The nuclear analytical methods (ENAA, SRXRF and XRF) were employed to study the effect of iodine deficiency on the metal ion changes during the stage of brain development, combined with biochemical methods. The results show that the distributions of iron, copper and zinc varied to different extent in different brain regions and subcellular fractions of the ID rat brains. These distributional changes of trace elements might be associated with the brain damage caused by the iodine deficiency. (author)
Carbonyl sulfide (COS), a colorless gas, is a side product of industrial procedures sure as coal hydrogenation and gasification. It is structurally related to and is a metabolite of carbon disulfide. COS is metabolized in the body by carbonic anhydrase to hydrogen sulfide (H{sub 2}S), which is thought to be responsible for COS toxicity. No threshold limit value for COS has been established. Results of these studies indicate COS (with an LC{sub 50} of 590 ppm) is slightly less acutely toxic than H{sub 2}S (LC{sub 50} of 440 ppm).
B vitamins and polymorphisms in genes coding for enzymes involved in one-carbon metabolism may affect DNA synthesis and methylation and thereby be implicated in carcinogenesis. Previous data on vitamins B2 and B6 and genetic polymorphisms other than those involving MTHFR as risk factors for gastric cancer (GC) are sparse and inconsistent. In this case-control study nested within the European Prospective Investigation into Cancer and Nutrition cohort, cases (n = 235) and controls (n = 601) were matched for study center, age, sex, and time of blood sampling. B2 and B6 species were measured in plasma, and the sum of riboflavin and flavin mononucleotide was used as the main exposure variable for vitamin B2 status, whereas the sum of pyridoxal 5'-phosphate, pyridoxal, and 4-pyridoxic acid was used to define vitamin B6 status. In addition, we determined eight polymorphisms related to one-carbon metabolism. ...
This feasibility study of the uve Institut fuer Technische Chemie und Umweltschutz GmbH discusses the scientific and technical fundamentals of a catalytic process for complete removal of organic pollutants (PAH, H-HC, PCB, phenols, nitro-aromatics and organometallic compounds, e.g. from polluted soil and groundwater) by thermal-catalytic cracking and conversion into simple gases. The process is based on the catalytic reaction of the hydrocarbon compounds with water vapour in the temperature range of 700-900 degrees centigrade. The resulting gas mixtures consist mainly of hydrogen, carbon monoxide, carbon dioxide and methane which can be used as fuels, e.g. for heating or in gas engines. The process is an alterntive to combustion. It is therefore well suited whenever the pollutant to be removed is already mixed with water or water vapour and wherever in-situ removal would be too great a hazard. [Deutsch] Die vorliegende Machbarkeitsstudie aus ...
We present ultraviolet through far-infrared (FIR) surface brightness profiles for the 75 galaxies in the Spitzer Infrared Nearby Galaxies Survey (SINGS). The imagery used to measure the profiles includes Galaxy Evolution Explorer UV data, optical images from Kitt Peak National Observatory, Cerro Tololo Inter-American Observatory, and Sloan Digital Sky Survey, near-IR data from Two Micron All Sky Survey, and mid- and FIR images from Spitzer. Along with the radial profiles, we also provide multi-wavelength asymptotic magnitudes and several nonparametric indicators of galaxy morphology: the concentration index (C 42), the asymmetry (A), the Gini coefficient (G), and the normalized second-order moment of the brightest 20% of the galaxy's flux (M-bar20). In this paper, the first of a series, we describe the technical aspects regarding the surface photometry, and present a basic analysis of the global and structural properties of the SINGS galaxies at different wavelengths. The homogeneity ...
The metabolism of organic matter in the coastal regions of the ocean may significantly affect the oceanic carbon budget. This paper describes the high percentage (30%) of oceanic oxidation that occurs in coastal areas and the impact of this metabolism on the carbon cycle and climate of earth. Organic metabolism in the ocean appears to be a source of carbon dioxide release into the atmosphere. Oxidation in the coastal zone is of special interest, as it is likely influenced by anthropogenic activity. Recommendations for future research on this topic are proposed. 129 refs., 2 figs., 6 tabs.
The mechanisms underlying the pathogenesis of estrogen-induced breast carcinogenesis remain unclear. The present study investigated the roles of estrogen metabolism and oxidative stress in estrogen-mediated mammary carcinogenesis in vivo. Female August Copenhagen Irish (ACI) rats were treated with 17b-estradiol (E2), the antioxidant vitamin C, the estrogen metabolic inhibitor a-naphthoflavone (ANF), or cotreated with E2 + vitamin C or E2 + ANF for up to 8 months. E2 (3 mg) was administered as an subcutaneous implant, ANF was given via diet (0.2%) and vitamin C (1%) was added to drinking water. At necropsy, breast tumor incidence in the E2, E2 + vitamin C and E2 + ANF groups was 82, 29 and 0%, respectively. Vitamin C and ANF attenuated E2-induced alterations in oxidative stress markers in b...
The elucidation on the metabolic products of the {sup 99}mTc-antibody conjugates may provide insights and approaches that would reduce the undesirable deposition of radioactive species in normal tissue. In this investigation, the radiolabeled species in blood, urine, bile and extracts of liver and kidney obtained at different times after the injection of a model antibody, {sup 99}mTc, into mice were analyzed with various chromatographic methods. Ninety-nine to 100% of the radioactivity in serum was associated with intact Mab 170. The radioactivity in liver homogenate extract was strictly protein-bound to either intact Mab or low molecular weight species (LMW). In kidney extracts, the majority of the radioactivity was protein bound {sup 99}mTc, with less than 8% of the activity being non- protein bound . Multiple {sup 99}mTc -containing protein and non-protein species were found in urine and bile. Evidence supporting the presence of {sup 99}mTc-cysteine and {sup ...
ObjectivesThe main objective of this study is to address the following specific questions: 1. Are the delayed effects of poor early diet on whole organism performance and senescence contingent on, or exacerbated by, the subsequent occurrence of compensatory growth? 2. Does the rate of growth influence levels of resting metabolism and/or oxidative stress, and if so, for how long does this persist? 3. How are the levels of early nutrition, growth, resting metabolism and oxidative stress linked to the lev [continued...]DescriptionIt is now widely appreciated that, while animals may appear to recover from periods of poor food quality or quantity experienced in early development, adverse effects may occur later in adult life. Such effects can influence the performance of complete cohorts of animals, and have important consequences for population dynamics. The reasons why such delayed effects occur across the animals' lifetimes ...
A study has been carried out to investigate whether the action of triclabendazole (TCBZ) against Fasciola hepatica is altered by inhibition of drug metabolism. The cytochrome P450 (CYP 450) enzyme pathway was inhibited using ketoconazole (KTZ) to see whether a TCBZ-resistant isolate could be made more sensitive to TCBZ action. The Oberon TCBZ-resistant and Cullompton TCBZ-susceptible isolates were used for these experiments. The CYP 450 system was inhibited by a 2-h pre-incubation in ketoconazole (40??M), then incubated for a further 22?h in NCTC medium containing either KTZ, KTZ?+?nicotinamide adenine dinucleotide phosphate (NADPH) (1?nM), KTZ?+?NADPH?+?TCBZ (15??g/ml), or KTZ?+?NADPH?+?triclabendazole sulphoxide (TCBZ.SO; 15??g/ml). Changes to fluke ultrastructure following drug treatmen...
In this study, six groups of rats were fed as follows: Groups 1 and 2 were fed formulated diets supplemented with zinc or without zinc respectively. Groups 3 and 4 were fed formulated diets supplemented with zinc plus phytic acid extracted from sweet potato (Ipomea batatas) or commercial phytic acid respectively. Groups 5 and 6 were fed formulated diets supplemented with phytic acid extract from sweet potato or commercial phytic acid respectively. The animals were fed for three weeks and then sacrificed The activities of key enzymes of carbohydrate and lipid metabolism as well as transaminases in the liver were determined. Blood glucose level was also assessed. Phytic acid extract consumption from sweet potato and commercial phytic acid plus zinc supplement lowered blood glucose levels. There was no significant change in the activity of 6-phosphogluconate dehydrogenase among the groups. Similarly, phytic acid supplementation showed no ...
The disposition of three (1-/sup 14/C)-chlorododecanes (MCDD, PCDD I and PCDD II; 17.4%, 55.9%, and 68.5% chlorination) was studied in C57Bl mice. (1-/sup 14/C)-lauric acid (LA) was studied as reference compound. Fifty-two percent (MCDD), 32% (PCDD I), and 8% (PCDD II) of the radioactive doses were exhaled as /sup 14/CO/sub 2/ during 12 h after i.v. injection. Similar results were obtained after p.o. administration. In addition to a marked labelling of the liver and fat, the distribution patterns observed at 24 h after administration revealed an uptake of radioactivity in tissues with high cell turnover/high metabolic activity, e.g., intestinal mucosa, bone marrow, salivary glands and thymus. The concentration of radioactivity in these sites and the exhalation of /sup 14/CO/sub 2/, which were inverse to the degree of chlorination, indicate that the chloroalkanes are degraded to metabolites which can be utilized in the ...
Perinatal exposure to cadmium (Cd) or methylmercury (MeHg) results in impaired neurodevelopment. Thyroid hormone is essential for normal brain development. However, the issue whether Cd or MeHg, especially at low doses, interrupts thyroid hormone action remains to be investigated. In the present study, effects of perinatal exposure to low levels of Cd or MeHg on thyroid hormone metabolism were examined using metallothionein I and II (MT-I/II) null or wild-type neonatal mice. Dams were exposed to 10 mg/L water of Cd or 5 mg/kg chow of MeHg from gestational day 0 to post-natal day 10 (PND 10). Sera, livers and brains were collected from neonates on PND 10. Iodothyronine deiodinase activities and serum thyroxine (T4) concentrations were measured. MeHg exposure failed to induce changes in serum T4 levels and liver type 1 deiodinase (D1) and brain type 2 deiodinase (D2) activities regardless of the MT genotype. However, exposure to MeHg resulted in ...
The authors used studies of local cerebral metabolic rate for glucose (LCMRGlc) to examine development of cerebral organization in 5 days to 1 year old children. A group (n=8) of infants with diverse pediatric disorders allowed investigation of developmental changes in LCMRGlc, while also providing relevant clinical management information. Patients consisted of questionable and definite neonatal seizures, cerebral embolism from cardiac sources, and otherwise normal infants with facial nevi with consideration of Sturge-Weber. Gradual increase in cortical LCMRGlc coincides with suppression of intrinsic subcortical reflexes present in all newborns. Two retarded children (2 years old) showed LCMRGlc developmental patterns of a few days old, which corresponded to their functional and mental status. These studies illustrate great potential of PET to study normal and altered states of human brain development.
Objective To demonstrate clinical features of a patient subgroup presenting with polycystic ovary syndrome (PCOS) without polycystic ovary morphology. Design Retrospective study. Setting Hospital-based IVF center. Patient(s) In the present study, 876 PCOS patients were selected from women who visited the Reproductive Medicine Center at Shandong Provincial Hospital, Shandong University, between September 2004 and October 2006. Women with PCOS were divided into two groups based on ultrasound image: group A, PCOS patients with classic polycystic ovary (n = 800); group B, PCOS patients without polycystic ovary morphology (n = 76). The following available data were analyzed in the large cohort of women: body height, weight, waistline, hip circumference, hirsutism scores, family history, serum s...
These studies were undertaken to assess the effects of increased galactose (v increased glucose) metabolism via the polyol pathway on vascular filtration function in the kidneys, eyes, nerves, and aorta. Quantitative radiolabeled tracer techniques were used to assess glomerular filtration rate (GFR) and regional tissue vascular clearance of plasma 131I-bovine serum albumin (BSA) in five groups of male Sprague-Dawley rats: nondiabetic controls, streptozotocin-diabetic rats, nondiabetic rats fed a 50% galactose diet, diabetic rats treated with sorbinil (an aldose reductase inhibitor), and galactose-fed rats treated with sorbinil. Sorbinil was added to the diet to provide a daily dose of approximately .2 mmol/kg body weight. After 2 months of diabetes or galactose ingestion, albumin clearance was increased twofold to fourfold in the eye (anterior uvea, choroid, and retina), sciatic nerve, aorta, and kidney; GFR was increased approximately twofold ...
Characteristics of basal and insulin-stimulated glucose utilization by perifused adipocytes have been investigated by measuring the formation of "3HOH from D-(5-"3H) glucose. At a glucose concentration of 0.55 mmol/L, basal glucose utilization ranged from 0.5 to 1.0 nmol/min/10(6) cells. Perifused adipocytes showed a maximal response to insulin of a threefold to fourfold increase in the conversion of (5-"3H) glucose to "3HOH with a half-maximal response at an insulin concentration of 20 microU/mL. The response to insulin was blocked by phlorizin and cytochalasin B, competitive inhibitors of glucose transport, consistent with an effect of insulin on glucose transport. Insulin increased the Vmax for glucose metabolism but had no effect on the apparent affinity for glucose utilization. The characteristics of glucose utilization and the stimulation of glucose metabolism by insulin in the perifused adipocyte are therefore similar to characteristics ...
Renal osteodystrophy is a metabolic bone disease and a common complication of end-stage chronic renal failure and maintenance dialysis treatment. In this study, we examined the correlation between quantifying bone scintigraphy and serum biochemical markers in hemodialysis patients. Bone scintigraphy with technetium-99m-hydroxy-methylene-diphosphonate ("9"9"mTc-HMDP) was performed on 28 patients on maintenance hemodialysis. Bone scintigraphy was performed using a standard protocol and was quantified by setting regions of interest (ROIs) over selected regions. The bone-to-soft-tissue ratio (B/ST ratio) at each region was calculated in all patients. The B/ST ratios were then compared with serum biochemical markers. The B/ST ratio for the skull correlated well with serum bone-specific alkaline phosphatase (BAP) (r=0.735, p<0.001), serum deoxypyridinoline (DPD) (r=0.806, p<0.001) and intact parathyroid hormone (intact PTH) (r=0.701, ...
Summary The objective of this study was to examine the role of root carbohydrate levels and metabolism in the waterlogging tolerance of contrasting mung bean genotypes. An experiment was conducted with two cultivated mung bean (Vigna radiata) genotypes viz., T44 (tolerant) and Pusa Baisakhi (PB) (susceptible), and a wild Vigna species Vigna luteola under pot-culture to study the physiological and molecular mechanism of waterlogging tolerance. Waterlogging resulted in decrease in relative water content (RWC), membrane stability index (MSI) in root and leaf tissues, and chlorophyll (Chl) content in leaves, while the Chl a/b ratio increased. Waterlogging-induced decline in RWC, MSI, Chl and increase in Chl a/b ratio was greater in PB than V. luteola and T44. Waterlogging caused decline in tot...
Abstract Plant metabolomics has been well established and applied across multiple fields including medicine, biotechnology, and environmental sciences in the post-genomic era. The Chenopodiaceae C3 halophyte Suaeda salsa is the most important plant species in the vegetation of saline soil and even intertidal zone in the Yellow River Delta, which is economically consumed as food, widely used as a bioindicator of environmental stresses (salinity, drought, and pollution) and typically applied for the phyto-remediation of degraded wetland. However, no global studies have been focused on the metabolic profile of this halophyte which is widely applied in environment related research areas. In metabolomics, the first crucial step is the preparation of plant samples. In this work, several strategi...
Abstract Background: Obstructive sleep apnea (OSA), a highly prevalent condition, is independently associated with increased risks of developing type 2 diabetes mellitus (T2D) and metabolic syndrome. It is unclear, however, if the severity of OSA has any impact on glycemic control among patients with T2D. We therefore aimed to determine the independent association between OSA severity and glycosylated hemoglobin (HbA1c) in patients with T2D. Methods: This was an observational cross-sectional study of 52 consecutive patients attending the diabetes obesity clinic between January 2008 to February 2010 with risk factors for sleep apnea and who underwent polysomnography study. Clinical, demographic, and lifestyle data were recorded using a questionnaire. Results: Prevalence of OSA in this clini...
To determine a rat strain appropriate for carcinogenicity testing of FYX-051, a xanthine oxidoreductase inhibitor, we performed a 4-week oral toxicity study by administering 0.3, 1 and 3 mg/kg, and 1, 3 and 10 mg/kg of FYX-051 to male Sprague-Dawley (SD) and Fischer (F344) rats, respectively. Histopathology revealed that the degree of FYX-051-induced nephropathy was 3-fold stronger in SD rats than in F344 rats. Our previous study demonstrated that the key factor of species differences in FYX-051-induced nephropathy is purine metabolism. This observation led us to examine the involvement of purine metabolism in differences among two strains of rats. However, purine metabolism was proven not to be implicated as an important factor. Subsequently, other factors responsible for the strain differences were examined. FYX-051-induced increases in plasma xanthine concentrations were higher ...
The penetrance of Lebers hereditary optic neuropathy (LHON) in families with primary mitochondrial DNA (mtDNA) mutations is very complex. Matrilineal and nuclear genetic background, as well as environmental factors, have been reported to be involved in different affected pedigrees. Here we describe two large Chinese families that show a striking difference in the penetrance of LHON, in which 53.3% and 15.0% of members were affected (Pin vivo mitochondrial oxidative metabolism as described in a previous study. Evolutionary analysis failed to indicate any putatively pathogenic mutation that cosegregated with G11778A in these two pedigrees. Our results suggest that the variable penetrance of LHON in the two Chinese families is independent of both their mtDNA haplotype background and a seconda...
Mobility reduction induced by the growth and metabolism of bacteria in high-permeability layers of heterogeneous reservoirs is an economically attractive technique to improve sweep efficiency. This paper describes an experimental study conducted in sandpacks using an injected bacterium to investigate the strength and stability of microbial plugs in porous media. Successful convective transport of bacteria is important for achieving sufficient initial bacteria distribution. The chemotactic and diffusive fluxes are probably not significant even under static conditions. Mobility reduction depends upon the initial cell concentrations and increase in cell mass. For single or multiple static or dynamic growth techniques, permeability reduction was approximately 70% of the original permeability. The stability of these microbial plugs to increases in pressure gradient and changes in cell physiology in a nutrient-depleted environment needs to be ...
Summary 1.-The metabolic theory of ecology (MTE) predicts that, after correcting for body mass variation among organisms, the rates of most biological processes will vary as a universal function of temperature. However, empirical support for -universal temperature dependence- (UTD) is currently equivocal and based on studies of a limited number of traits. 2.-In many ectothermic animals, the rate at which females produce mature eggs is temperature dependent and may be an important factor in determining the costs of reproduction. 3.-We tested whether the rate of egg maturation in marine turtles varies with environmental temperature as predicted by MTE, using the time separating successive clutches of individual females to estimate the rate at which eggs are formed. We also assessed the pheno...
Abstract Strains of Pseudomonas syringae are effective in controlling postharvest diseases of citrus fruits, and antagonistic activity has been correlated with in vitro production of lipodepsipeptides. Additionally, biocontrol agents can induce a range of defence mechanisms of resistance in citrus tissue that result in a broad spectrum of metabolic modifications, such as systemic acquired resistance, induced systemic resistance and production of reactive oxygen species. The aim of this study was to evaluate the expression of syringomycin (syrB1) and syringopeptin (sypA) synthetase genes from P.syringae pv. syringae biocontrol strains in vitro on different culture media and in vivo on citrus fruits (Citrus sinensis cv. Tarocco) during the interaction with Penicillium digitatum by quantitati...
Abstract Tumor necrosis factor (TNF)- is a pro-inflammatory cytokine associated with psoriasis pathogenesis. Anti-TNF- therapies are effective in psoriasis. A significant weight gain has been reported in patients treated with anti-TNF- agents. The aim of the present study was to evaluate the body composition changes in psoriatic patients receiving anti-TNF- therapies according with disease phenotype. Forty patients affected with psoriasis were followed up for 24 weeks and divided into two groups: psoriasis vulgaris (PsO) and psoriatic arthritis (PsA). Anthropometric, blood biochemical, body composition parameters, resting metabolic rate, and disease activity indexes were measured at baseline and at week 24. After 24 weeks of anti-TNF- administration, the disease activity indexes and concen...
Periphyton is typically a heterogeneous assemblage of filamentous and single celled photoautotrophic and heterotrophic micoorganisms suspended in a mucopolysaccharide matrix which they produce. By definition, the assemblage is attached to a substratum such as rock, sediment, or plant in an aquatic environment. Microtechniques with high spatial and temporal resolution are required to define metabolic interactions among the heterotrophic and autotrophic constituents, and between periphyton and its environment. This study used oxygen sensitive microelectrodes with tip diameters of < 30 m to investigate the effects of photosynthesis and respiration on the oxygen dynamics of several diverse periphyton communities both in situ and in laboratory microcosms. A novel flow-through system that utilized TSP radiotracer and that permitted manipulation of the velocity, flushing rate, and oxygen concentration of overlying water was developed to investigate ...
It is a useful hypothesis to thing of the reaction to protein deprivation as made up of two parts. First there is an initial adaptation involving rapid losses of protein. This is followed by slow continuing depletion. When considering two organ groups, such as the liver and muscle, it appears that the curve of urinary nitrogen excretion reflects the different parts they play in these two phases. The changes in the relative amounts of protein in different organs results in an alteration in the pattern of body protein at the level of the organ, the tissue and the cell. These changes are themselves the result of altered rates of synthesis and breakdown. The questions that must be asked and hopefully will be answered with the help of isotopes, are how these changes are brought about, how they are inter-related and controlled, and what is their significance? This paper contains a discussion of the few results that have been obtained so far. 1 fig.
The present study was aimed at investigating effects of nickel (NiCl2) on secretion of testosterone (T), cell viability, ultrastructure and apoptosis in mouse Leydig cells. Testosterone release was measured after 48h of culture with 15.67, 31.25, 62.5, 125, 250, 500 and 1000mmol/L NiCl2 or without NiCl2 using radioimmunoassay. Cell viability was assessed by a MTT (metabolic activity assay). Quantification of apoptotic cells was performed using TUNEL assay and the ultrastructural changes were analyzed using transmission electron microscopy. The viability was decreased after addition of >=250mmol/L NiCl2. A concentration-dependent depression of T production was observed. The percentage of apoptotic cells was significantly increased only after addition of 125, 250 and 1000mmol/L NiCl2. After ...
The objective of this study was to determine whether walking and running at different treadmill speeds resulted in different metabolic and cardiovascular responses in the vastus lateralis (VL) and lateral gastrocnemius (LG) by examining metabolite accumulation and tissue oxygen saturation. Ten healthy subjects (6 males, 4 females) completed a submaximal treadmill exercise test, beginning at 3.2?km?h?1 and increasing by 1.6?km?h?1 increments every 3?min until reaching 85% of age-predicted maximal heart rate. Muscle tissue oxygenation (SO2), total hemoglobin (HbT) and interstitial hydrogen ion concentration ([H+]) were calculated from near infrared spectra collected from VL and LG. The [H+] threshold for each muscle was determined using a simultaneous bilinear regression. Muscle and treadmil...
One of the research challenges in oncology is to develop new biochemical methods for noninvasive tumor therapy evaluation to determine whether the chemotherapeutics is effective. Vascular endothelial growth factor (VEGF) was labeled with radioiodine and evaluated in vitro as well as in vivo, using A2058, a melanoma cell line overexpressing VEGFR-1 and -2. Saturation binding analysis with [{sup 125}I]-VEGF resulted in a K {sub d} of 0.1 nM. Internalization assays indicate the preserved ligand induced internalization and metabolization of the tracer. Biodistribution studies with [{sup 123}I]-VEGF in wild type and A2058 tumor-bearing athymic mice showed low background activity and a tumor to reference tissue ratio of maximum 6.12. These results suggest that [{sup 123}I]-VEGF is a potentially suitable tracer for tumor therapy evaluation.
The clinical use of "1"8F-fluorodeoxyglucose (FDG) positron emission tomography in monitoring anticancer treatment is expanding. At the same time a number of radiotracers aiming to image different aspects of tumour biology such as proliferation and apoptosis are being developed. However, the factors determining changes of radiotracer uptake parameters in response to treatment are not well understood. In many cases, cellularity may be the primary determinant of changes of FDG uptake and may confound the interpretation of metabolic changes. Early imaging assessments have in some cases showed transient increases of uptake parameters, commonly termed 'flares', which are likely to be unaffected by cellularity and directly reflect pharmacodynamics at a cellular level. In this review a number of settings where molecular imaging 'flares' have been described are discussed. Such changes may often be clinically informative and warrant careful study as ...
In the present study the authors have shown that glycoproteins are present in the plasma membrane of Acanthamoeba castellanii by utilizing different radioactive labeling techniques. Plasma membrane proteins in the amoeba were iodinated by "1"2"5I-lactoperoxidase labeling and the solubilized radiolabeled glycoproteins were separated by lectin-Sepharose affinity chromatography followed by polyacrylamide gel electrophoresis. The periodate/NaB"3H_4 and galactose oxidase/NaB"3H_4 labeling techniques were used for labeling of surface carbohydrates in the amoeba. Several surface-labeled glycoproteins were observed in addition to a diffusely labeled region with M_r of 55,000-75,000 seen on electrophoresis, which could represent glycolipids. The presence of glycoproteins in the plasma membrane of Acanthamoeba castellanii was confirmed by metabolic labeling with ["3"5S]methionine followed by lectin-Sepharose affinity chromatography and polyacrylamide gel ...
Radioiodinated carbohydrates such as 2-deoxy-2-iodo-D-glucose and 3-deoxy-3-iodo-D-glucose undergo facile chemical or in vivo deiodination which precludes their use as radiotracers of glucose metabolism in tissues. To overcome the problems resulting from in vivo deiodination, we explored the concept of stabilizing radioiodide on a model carbohydrate, (E)-C-3-iodovinyl-D-allose (10) as an iodovinyl moiety. This agent did not exhibit brain specificity but showed low in vivo deiodination which demonstrated for the first time that radioiodide can be stabilized on a carbohydrate. The goal of this study was to develop a deoxy-branched carbohydrate with radioiodide stabilized as a vinyliodide with the objective of achieving high brain uptake. 10 refs., 1 fig., 1 tab.
Radioiodinated carbohydrates such as 2-deoxy-2-iodo-D-glucose and 3-deoxy-3-iodo-D-glucose undergo facile chemical or in vivo deiodination which precludes their use as radiotracers of glucose metabolism in tissues. To overcome the problems resulting from in vivo deiodination, we explored the concept of stabilizing radioiodide on a model carbohydrate, (E)-C-3-iodovinyl-D-allose as an iodovinyl moiety. This agent did not exhibit brain specificity but showed low in vivo deiodination which demonstrated for the first time that radioiodide can be stabilized on a carbohydrate. The goal of this study was to develop a deoxy-branched carbohydrate with radioiodide stabilized as a vinyliodide with the objective of achieving high brain uptake. (author).
Abstract This study reports the effects of varying concentrations of copper sulfate on the metabolic and gene transcriptional profile of a recombinant Chinese hamster ovary (CHO) cell line producing an immunoglobulin G (IgG)-fusion protein (B0). Addition of 50 M copper sulfate significantly decreased lactate accumulation in the cultures while increasing viable cell density and protein titer. These changes could be seen from day 6 and became increasingly evident with culture duration. Reducing the copper sulfate concentration to 5 M retained all the above beneficial effects, but with the added benefit of reduced levels of the aggregated form of the B0 protein. To profile the cellular changes due to copper sulfate addition at the transcriptional level, Affymetrix CHO microarrays were used to...
Apelin is a peptide known as the ligand of the G-protein-coupled receptor APJ. Several active apelin forms exist such as apelin-36, apelin-17, apelin-13, and the pyroglutamated form of apelin-13. Apelin and APJ are expressed in the central nervous system, particularly in the hypothalamus and in many peripheral tissues. Apelin has been shown to be involved in the regulation of cardiovascular and fluid homeostasis, food intake, cell proliferation, and angiogenesis. In addition to be an ubiquitous peptide, apelin is also produced and secreted by adipocytes and thus considered as an adipokine. This has opened a new field of investigation establishing a link between apelin and metabolic disorders (obesity, type 2 diabetes, etc.) which is the focus of the present review. Several studies, but not...
4-Methylcoumarins that possess two hydroxyl groups ortho to each other in the benzenoid ring have shown to have excellent antioxidant and radical-scavenging properties in different experimental models. Furthermore, they cannot be metabolized by the liver P450 monoxygenases and thus cannot form 3,4-coumarin epoxides, which are believed to be mutagenic. Herein, we present a study on the structure activity relationship of eight synthetic 4-methylcoumarins, carried out by employing a series of different chemical cell-free tests. These compounds were tested by means of three assays involving one redox reaction with the oxidant (DPPH assay, ABTS+ assay and FRAP). Other assays were employed to evaluate the antioxidant properties of the coumarins under investigation against NO, O2- and HClO, which...
Hepatocellular carcinoma (HCC) represents a major health problem as it afflicts an increasing number of patients worldwide. Albeit most of the risk factors for HCC are known, this is a deadly syndrome with a life expectancy at the time of diagnosis of less than 1?year. Definition of the molecular principles governing the neoplastic transformation of the liver is an urgent need to facilitate the clinical management of patients, based on innovative methods to detect the disease in its early stages and on more efficient therapies. In the present study, we have combined the analysis of a murine model and human samples of HCC to identify genes differentially expressed early in the process of hepatocarcinogenesis, using a microarray-based approach. Expression of 190 genes was impaired in murine ...
The aim of this study was the evaluation of contralateral hip fractures after a previous hip fracture. For this retrospective analysis patients were selected from the database of the LUMC, a teaching hospital in the south-west of the Netherlands. We analyzed all patients with a second fracture of a hip between 1992 and 2007. The exclusion criteria were high impact trauma and patients with diseases or medication known to have a negative effect on bone metabolism. A total of 1,604 hip fractures were identified. The possible predictive factors for the second fracture and descriptive statistics related to surgery (Hb and HT before and after the operation, total amount of intra- and postoperative blood loss, type of osteosynthesis, complications, time of death after the last fracture, time betw...
Large scale production of monoclonal antibodies has been accomplished using bioreactors with different length to diameter ratios, and diverse impeller and sparger designs. The differences in these physical attributes often result in dissimilar mass transfer, mechanical stresses due to turbulence and mixing inside the bioreactor that may lead to disparities in cell growth and antibody production. A rational analysis of impeller design parameters on cell growth, protein expression levels and subsequent antibody production is needed to understand such differences. The purpose of this study was to examine the impact of Rushton turbine and marine impeller designs on Chinese hamster ovary (CHO) cell growth and metabolism, and antibody production and quality. Experiments to evaluate mass transfer...
The effect of 5,5′-diphenylhydantoin on thyroxine metabolism was examined in five normal volunteers. Intravenous injection of radiothyroxine was followed by a 10-12 day control and subsequent...Full Text Available
The metabolism of 14C-labeled fatty acids and triacylglycerols was followed in intact germinating oil palm seedlings as well as in tissue slices. In the germinating seedling, the shoot contained...Full Text Available
Objective. To determine relative influences of intrauterine growth restriction (IUGR) and preterm birth on risks of cardiovascular, renal, or metabolic dysfunction in adolescent...Full Text Available
Six genes involved in the heparan sulfate and heparin metabolism pathway, DSEL (dermatan sulfate epimerase-like), EXTL1 (exostoses (multiple)-like 1), HS6ST1...Full Text Available
It has become increasing clear that alterations in cellular metabolism have a key role in the generation and maintenance of cancer. Some of the metabolic changes can be attributed to the activation...Full Text Available
The current obesity pandemic is expected to result in considerable downstream morbidity, mortality and incremental costs to health care systems around the world. The major metabolic complications of...Full Text Available
BackgroundComplex etiology and pathogenesis of pathophysiological components of the cardio-metabolic syndrome have been demonstrated in humans and animal models.Methodology/Principal...Full Text Available
The insulin/IGF-1 signaling (IIS) pathway is a conserved regulator of longevity, development, and metabolism. In Caenorhabditis elegans IIS involves activation of DAF-2 (insulin/IGF-1...Full Text Available
BACKGROUND: Each component of metabolic syndrome (MS) conveys increased cardiovascular disease risk, but as a combination they become much more powerful. Vigorous early management of the syndrome may...Full Text Available
Choline (Cho)-containing phospholipids are the most abundant phospholipids in cellular membranes and play fundamental structural as well as regulatory roles in cell metabolism and signaling. Although...Full Text Available
The mechanism of metabolic energy production by malolactic fermentation in Lactococcus lactis has been investigated. In the presence of L-malate, a proton motive force composed of a membrane potential...Full Text Available
de Vito, Peter C. (Princeton University, Princeton, N.J.), and Jacques Dreyfuss. Metabolic regulation of adenosine triphosphate sulfurylase in yeast. J. Bacteriol. 88:1341–1348....Full Text Available
Host cells use metabolic signaling through the LXRα nuclear receptor to defend against Listeria monocytogenes infection. 25-Hydroxycholesterol is a natural ligand of LXRs that...Full Text Available
Basal or standard metabolic rate (SMR) has been found to exhibit substantial intraspecific variation in a range of taxa, but the consequences of this variation are little understood. Here we explore...Full Text Available
The influence of obesity on the metabolism of apolipoprotein B (apo B) in very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL), and low density lipoprotein (LDL) was investigated...Full Text Available
We sought to determine the prevalence of metabolic syndrome (MS) in patients with acute myocardial infarction and its effect on clinical outcomes. Employing data from the Korea Acute Myocardial Infarction...Full Text Available
Tamoxifen (TAM) is a selective estrogen receptor modulator widely used in the prevention and treatment of breast cancer. A major mode of metabolism of the major active metabolites of TAM, 4-OH-TAM...Full Text Available
Hydrolytic exoenzymes as indicators of metabolically active bacteria were investigated in four consecutive sapropel layers collected from bathyal sediments of the eastern Mediterranean Sea. For comparison,...Full Text Available
A commercial blend of essential oil (EO) compounds was added to a grass, maize silage, and concentrate diet fed to dairy cattle in order to determine their influence on protein metabolism by ruminal...Full Text Available
Energetically costly behaviours, such as flight, push physiological systems to their limits requiring metabolic rates (MR) that are highly elevated above the resting MR (RMR). Both RMR and MR during...Full Text Available
A paradoxical metabolic imbalance in inorganic phosphate occurs from the early onset of diabetes and may lead to a reduction of high energy phosphates and tissue hypoxia. These changes take place in...Full Text Available
To assess the effects of increasing the mineral content of parenteral nutrition solutions on the biochemical and radiological indicators of metabolic bone disease of prematurity 27 neonates who required...Full Text Available
There is increasing evidence of a biochemical link between lipid oxidation and bone metabolism. Paraoxonase 1 (PON1) prevents the oxidation of low-density lipoprotein (LDL) and metabolizes biologically...Full Text Available
The cofactor nicotinamide adenine dinucleotide (NAD+) has emerged as a key regulator of metabolism, stress resistance and longevity. Apart from its role as ...Full Text Available
Experiments were conducted to investigate indole-3-acetic acid (IAA) and abscisic acid (ABA) metabolism associated with postanthesis senescence of ovaries from nonpollinated muskmelon (Cucumis...Full Text Available
BackgroundObesity is one of the principal causative factors involved in the development of metabolic syndrome. AMP-activated protein kinase (AMPK) is an energy sensor that regulates...Full Text Available
Thiamin(e), also known as vitamin B1, is now known to play a fundamental role in energy metabolism. Its discovery followed from the original early research on the ‘anti-beriberi factor’...Full Text Available
To determine if medium and long chain fatty acids can be appropriately metabolized by species that normally produce 16 and 18 carbon fatty acids, homogenates of developing Cuphea wrightii, Carthamus...Full Text Available
The eastern oyster (Crassostrea virginica) developed neoplastic disorders when experimentally exposed both in the laboratory and field to chemically contaminated sediment from Black Rock Harbor (BRH), Bridgeport, Connecticut. Neoplasia was observed in oysters after 30 or 60 days of continuous exposure in a laboratory flow-through system to a 20 mg/L suspension of BRH sediment plus postexposure periods of 3, 30, or 60 days. Composite tumor incidence was 13.6% for both exposures. Tumor occurrence was highest in the renal excretory epithelium, followed in order by gill, gonad, gastrointestinal, heart, and embryonic neural tissue. Regression of experimental neoplasia was not observed when the stimulus was discontinued. In field experiments, gill neoplasms developed in oysters, deployed in cages for 30 days at BRH and 36 days at a BRH dredge material disposal area in Central Long Island Sound, and kidney and gastrointestinal neoplasms developed in caged oysters deployed 40 days in Quincy ...
Isotope ratios of cellulose and cellulose nitrate from aquatic Crassulacean acid metabolism (CAM) and non-CAM plants were determined. Cellulose oxygen istope ratios for all plants that grew together...Full Text Available
Radioiodinated 15-(p-iodophenyl)-3,3-dimethylpentadecanoic acid (DMIPP) has been prepared as a new terminal iodophenyl-substituted fatty acid containing dimethyl-branching at the beta-position. Iodine-125-labeled DMIPP showed rapid, high myocardial uptake (min, mean % injected dose/g) in fasted rats (5, 4.67; 30, 5.06; 60, 4.79; 120, 4.37), and also exhibited high heart:blood ratios (min, ratio) 5, 3:1; 30, 12:1; 60, 12:1; 120, 13:1. These data demonstrate an unanticipated much longer myocardial residence time with DMIPP (+/sub 1/2/ 7-8 h) than observed with either the 3-monomethyl (BMIPP) analogue (+/sub 1/2/ 30-45 min) or the rapidly metabolized straight-chain (IPP) analogue (+/sub 1/2/ 10-15 min). The (/sup 123/I)DMIPP is thus an excellent candidate for clinical evaluation of regional fatty acid metabolism under conditions where the uptake of energy substrates can be assessed independent of regional blood delivery. ...
Tree growth is mainly regulated by nitrogen (N) availability. Many plants exhibit enhanced growth and increased biomass or net primary productivity when exposed to higher atmospheric levels of carbon dioxide (CO_2), as N metabolism is regulated by signals that are derived from CO_2 metabolism. This study estimated N use by trees of 3 poplar species exposed for 3 years to free air CO_2 enrichment (FACE) in order to determine if CO_2 treatment affected the future N availability of the plantation. N uptake of fine roots and litter was measured throughout the first crop rotation. Results were then related to previously published variations in soil N content during the same period. Retranslocation from green leaves was studied, as well as processes determining N mobilization and immobilization. The study showed that elevated CO_2 concentrations significantly increased N-use efficiency, ...
A transplant experiment was conducted to determine whether standard metabolic rate (SMR) of a freshwater shrimp (Palaeomonetes paludosus) would be affected by exposure to trace element-enriched coal combustion waste (coal ash). Shrimp were transplanted into replicate cages in a coal ash-polluted site and a reference site for 8 months. The coal ash-polluted site was characterized by elevated sediment concentrations of As, Cd, Cr, Cu, Ni, Pb and Se compared to sediments in the reference site. After 8 months in the study sites, shrimp in the polluted site appeared to have accumulated As, Cd and Se from the habitat, but there were on differences in survival between the study sites. However, mean SMR of shrimp (measured as O{sub 2} consumption at rest) held in the polluted site was 51% higher than mean SMR of shrimp held in the reference site. The elevation in SMR indicates that the energetic costs of maintenance are greater for ...
A cross sectional study on the mineral density of the 3rd lumbar vertebral trabecular bone was carried out in 123 children less than 15 years old, comprising 44 controls, and 79 patients affected with conditions which are at risk for developing metabolic derangement of skeletal bone (34 patients taking antiepileptic drugs (AED), 29 undergoing glucocorticoid (GC) therapy and 16 bedridden patients), by using quantitative computed tomography (QCT) with a CaCO{sub 3} phantom. Serum Ca and alkaline-phosphatase (Alp) levels were measured at the time of QCT examinations in all. The results obtained were as follows: The QCT values in the control children showed neither age dependency nor a sexual difference before puberty. The QCT values in each group showed significant difference with one another; the control group>the AED group>the GC group>the bedridden group (p<0.05{approx}0.005). The serum Ca levels in each pathology group were ...
The aim of this study was to assess the utility of a radioimmunoconjugate containing a lead radionuclide for therapy and scintigraphy applications. The radioimmunoconjugate evaluated consisted of a bifunctional DOTA ligand and monoclonal antibody (MAb) B72.3 using athymic mice bearing LS-174T tumors, human colon carcinoma xenografts. In the studies reported here, the lead-203-DOTA complex itself was first demonstrated to have in vivo stability. MAb B72.3 was then conjugated with the DOTA ligand and labeled with "2"0"3Pb, and the immunoreactivity of B72.3 was maintained. The localization of the radioimmunoconjugate to tumor tissue and other select organs paralleled that of DOTA-"1"2"5I-B72.3, suggesting a similar metabolic pattern of the two radioimmunoconjugates. Thus, the DOTA-metal complex does not alter the behavior of the radioimmunoconjugate. Tumor localization of the "2"0"3Pb-DOTA-B72.3 conjugate was demonstrated with ...
Statements about the dynamic processes of uptake, transport, and deposition of Ca and Mg in norway spruce and Scots pine are made in this paper. Concerning the storage of these elements it is shown that there are great differences in their functional importance in cell metabolism. There is evidence that the role of Mg in enzyme and protein metabolism is of far greater significance for the understanding of Mg-deficiency symptoms than its function as the central atom of the chlorophyll complexes. In regard to the transport and especially to the incorporation of Ca into the needles differences between species were evident, expressing the special status of pine among the gymnosperms. With increasing needle age an accumulation of Ca-oxalate crystals, which are physiologically inert, could be proved for the studied conifers. This was interpreted as a 'detoxication' from surplus Ca to hold constant the level of the physiologically ...
Bone is a complex, highly structured, mechanically active, three-dimensional (3-D) tissue composed of cellular and matrix elements. We previously published a report on in situ collagen gelation using a rotary 3-D culture system (CG-RC system) for the construction of large tissue specimens. The objective of the current study was to evaluate the feasibility of bone tissue engineering using our CG-RC system. Osteoblasts from the calvaria of newborn Wistar rats were cultured in the CG-RC system for up to 3 wk. The engineered 3-D tissues were implanted into the backs of nude mice and calvarial round bone defects in Wistar rats. Cell metabolic activity, mineralization, and bone-related proteins were measured in vitro in the engineered 3-D tissues. Also, the in vivo histological features of the transplanted, engineered 3-D tissues were evaluated in the animal models. We found that metabolic activity increased in the engineered 3-D ...
{sup 188}Re is a {beta}{sup -} (Emax=2.12 MeV) and {gamma} (155 keV) emitter. Since its chemistry is similar to that of the largely employed tracer, {sup 99m}Tc, molecules of hyaluronic acid (HA) have been labelled with {sup 188}Re to produce a target specific radiopharmaceutical. The radiolabeled compound, i.v. injected in healthy mice, is able to accumulate into the liver after a few minutes. To study the effect of metabolic radiotherapy in mice, we have built a small gamma camera based on a matrix of YAP:Ce crystals, with 0.6x0.6x10 mm{sup 3} pixels, read out by a R2486 Hamamatsu PSPMT. A high-sensitivity 20 mm thick lead parallel-hole collimator, with hole diameter 1.5 mm and septa of 0.18 mm, is placed in front of the YAP matrix. Preliminary results obtained with various phantoms containing a solution of {sup 188}Re and with C57 black mice injected with the {sup 188}Re-HA solution are presented. To increase the space resolution and to ...
Bone-seeking radiopharmaceutical uptake (BSRU) was used to examine alveolar bone metabolism in a longitudinal study of tetracycline efficacy in beagle dogs. BSRU was measured in untreated control dogs and in beagles receiving either 250 mg or 500 mg oral tetracycline-HCl daily for 16 months. The rate of bone loss was determined for radiographs taken semiannually for a 6-month pretreatment period and for a 24-month treatment period. Measurements of BSRU obtained at month 16 of treatment were correlated with rates of bone loss determined radiographically in an attempt to determine whether BSRU was indicative of the subsequent rate of bone loss. A reduced rate of alveolar bone loss was found in the 500 mg tetracycline group at month 16 of the study relative to the untreated controls which was consistent with the decreased bone-seeking radiopharmaceutical uptake observed in this group. A significantly increased BSRU ...
Previous work suggests that supplemental ascorbic acid (AA) may inhibit intestinal copper absorption by stabilizing the less absorbable cuprous state. The authors studied copper absorption in healthy men (age 19-32) fed a constant diet with different amounts of ascorbic acid supplements. The 6 men were confined to a metabolic unit for the entire 14 week study. The basal diet consisted of a 7 day rotating menu which provided an average of 2.1 mg Cu/d and was adequate in all other nutrients except AA (5 mg/d). The basal diet was supplemented with either zero, 60, or 600 mg of AA daily, added to grape juice and consumed at each meal. All feces were collected. Blood was taken weekly for monitoring AA and copper status. Copper absorption was determined by both balance and "6"5Cu stable isotope techniques. As determined by fecal Cu excretion, varying intakes of AA between 0.1 to 10 times the RDA had no significant effect on ...
BackgroundBiodiesel or ethanol derived from lipids or starch produced by microalgae may overcome many of the sustainability challenges previously ascribed to petroleum-based fuels and first generation plant-based biofuels. The paucity of microalgae genome sequences, however, limits gene-based biofuel feedstock optimization studies. Here we describe the sequencing and de novo transcriptome assembly for the non-model microalgae species, Dunaliella tertiolecta, and identify pathways and genes of importance related to biofuel production.ResultsNext generation DNA pyrosequencing technology applied to D. tertiolecta transcripts produced 1,363,336 high quality reads with an average length of 400 bases. Following quality and size trimming, ~ 45% of the high quality reads were assembled into 33,307 isotigs with a 31-fold coverage and 376,482 singletons. Assembled sequences and singletons were subjected to BLAST similarity searches and annotated with Gene Ontology (GO) and ...
In this study, we measured the effects of different concentrations of paraquat (0,01 mM and 1,0 mM) on the 1-"1"4CO_2 and 6-"1"4CO_2 production of rabbit lung slices and isolated alveolar macrophages, in 20% and 95% oxygen phases respectively. A 95% oxygen phase induced an increase in the 6-"1"4C-glucose oxidation of control lung slices over a 3-hour period, while the increased activity of the pentose pathway over the first 2 hours started to decline during the third hour of incubation. Paraquat (1,0mM) in 20% oxygen caused a consistent increase in the 6-"1"4CO_2 production by lung slices, but in a 95% oxygen phase gradually inhibited the 6-"1"4C-glucose oxidation over a period of 3 hours. The pentose phosphate pathway was highly significantly stimulated by 1,0 mM paraquat in 20% and 95% oxygen over 3 hours. When isolated alveolar macrophages (viability 95%) were incubated in a 20% and 95% oxygen phase respectively, both the 6-"1"4C-glucose and 1-"1"4C-glucose ...
We recently found that injection of 2 mCi of yttrium 90 (90Y; approximately 23,000 rads) into normal canine knees stimulated glycosaminoglycan (GAG) synthesis by femoral condylar cartilage. The present investigation was conducted to determine whether radiation affects cartilage metabolism directly. Rates of GAG synthesis and degradation in normal canine articular cartilage were studied following irradiation. Cultured synovium from the same knees was treated similarly, to determine the effects of irradiation on hyaluronic acid synthesis. Twenty-four hours after exposure to 1,000 rads, 10,000 rads, or 50,000 rads, 35S-GAG synthesis by the cartilage was 93%, 69%, and 37%, respectively, of that in control, nonirradiated cartilage. The effect was not rapidly reversible: 120 hours after exposure to 50,000 rads, GAG synthesis remained at only 28% of the control level. Autoradiography showed marked suppression of 35S uptake by chondrocytes after ...
A three-dimensional, three-phase, multiple-component numerical simulator was developed to investigate transport and growth of microorganisms in porous media and the impacts of microbial activities on oil recovery. The microbial activities modeled in this study included: (1) growth, retention, chemotaxis, and end product inhibition of growth, (2) the formation of metabolic products, and (3) the consumption of nutrients. Major mechanisms for microbial enhanced oil recovery (MEOR) processes were modeled as follows: (1) improvement in sweep efficiency of a displacement process due to in situ plugging of highly-permeable production zones by cell mass or due to improved mobility control achieved by increasing the viscosity of the displacing fluid with a biopolymer, and (2) solubilization and mobilization of residual oil in porous media due to the reduction of the interfacial tension between oleic and aqueous phases by the production of a ...
The purpose of this study was to examine arachidonic acid (AA) metabolism and to characterize the type of adrenergic receptor (AR) involved in the production of the major metabolite of this fatty acid. ({sup 14}C)AA was incubated with GPT-rings and the radiolabelled products were extracted and separated by TLC method. The medium was also assayed for radiolabelled immunoreactive PG's (iPG's) and leukotrienes (LT) B4 and C4 by RIA or Enzyme immunoassay (EIA) after exposure to various AR agonists. ({sup 14}C)AA was incorporated into GPT-rings and metabolized mainly into iPGE2 and smaller amounts into PGF2{alpha}. Trace amounts of PGD2 and 6-keto-PGF1{alpha} but not LTB4 or LTC4 were detected by RIA and/or EIA. Incubation of GPT rings for 15 minutes with isoproterenol and salbutamol resulted in a significant increase of PGE2 synthesis (optimum conc: 10{sup {minus}7}, 10{sup {minus}7}M respectively). In ...
The purpose of this study was to examine arachidonic acid (AA) metabolism and to characterize the type of adrenergic receptor (AR) involved in the production of the major metabolite of this fatty acid. ["1"4C]AA was incubated with GPT-rings and the radiolabelled products were extracted and separated by TLC method. The medium was also assayed for radiolabelled immunoreactive PG's (iPG's) and leukotrienes (LT) B4 and C4 by RIA or Enzyme immunoassay (EIA) after exposure to various AR agonists. ["1"4C]AA was incorporated into GPT-rings and metabolized mainly into iPGE2 and smaller amounts into PGF2#alpha#. Trace amounts of PGD2 and 6-keto-PGF1#alpha# but not LTB4 or LTC4 were detected by RIA and/or EIA. Incubation of GPT rings for 15 minutes with isoproterenol and salbutamol resulted in a significant increase of PGE2 synthesis (optimum conc: 10"-"7, 10"-"7M respectively). In contrast, dobutamine, norepinephrine, phenylnephrine ...
Nitrogen metabolism and protozoa production rate using "1"4C-choline as marker were studied on 9 adult male crossbred (Tharparker x Brown Swiss) rumen fistulated animals divided into 3 groups (A, B and C). All the animals were fed concentrate mixture and wheatstraw. However, groundnut cake (GNC) in concentrate mixture was untreated in group A, 50 per cent formaldehyde treated in group B and 100 per cent formaldehyde treated in group C. Although, DM intake was similar in these groups but water intake was significantly (P<0.05) higher in control group. Total-N, ammonia-N and blood urea were significantly lower in group B and C as compared to group A. Apparent CP digestibility was not affected by addition of formaldehyde treated GNC at 50 and 100 per cent levels. However, N balances increased significantly (P<0.05) due to addition of protected protein in diet. Protozoal pool as well as production rate were significantly (P<0.01) decreased ...
The advancement of bioprocess monitoring will play a crucial role to meet the future requirements of bioprocess technology. Major issues are the acceleration of process development to reduce the time to the market and to ensure optimal exploitation of the cell factory and further to cope with the requirements of the Process Analytical Technology initiative. Due to the enormous complexity of cellular systems and lack of appropriate sensor systems microbial production processes are still poorly understood. This holds generally true for the most microbial production processes, in particular for the recombinant protein production due to strong interaction between recombinant gene expression and host cell metabolism. Therefore, it is necessary to scrutinise the role of the different cellular compartments in the biosynthesis process in order to develop comprehensive process monitoring concepts by involving the most significant process variables and their ...
Repeated exposure to cold air reduces the metabolic response to cold air exposure in man. The purpose of this investigation was to measure the change in resting metabolic rate (RMR) with exposure to 22C air and 4C air during a 12 day period. Four women sat in 22C air for 45 min followed by 45 min in 4C air each day for ten days. The authors measured RMR during a 45 min period in 22C air followed by 45 min in 4C air on four days. All subjects began their morning exposures on a Monday within 2 days of the onset of menses completing the study on a Friday, 12 days later. Subjects dressed in a T-shirt, shorts and cotton socks. During 45 min of exposure to warm air, RMR remained steady at 10% of VO{sub 2peak} on Day 1 and 10% on Day 5. RMR during exposure to warm air significantly increased to 13% of VO{sub 2peak} on Day 8 and remained elevated at 13% on Day 12. During exposure to cold air RMR peaked at 31% of CO{sub 2peak} by ...
During last decade, considerable interest has been focused to assess the influence of human activities on ecosystems. The increasing trend in the atmospheric concentration of CO{sub 2} has been predicted to continue till the next century and the amount of nitrogen deposition in the northern hemisphere has increased markedly. Substantial interest has been focused on predicting how these changes will affect on plants. Most boreal mire ecosystems are dominated by mosses of the genus Sphagnum, the litter of which constitutes the main component in the peat deposits and is an important CO{sub 2} sink via peat formation. Since virtually nothing was known about the growth response of peat mosses to elevated concentrations of CO{sub 2} and alerting changes in species composition were detected in the sensitive ombrotrophic mire vegetation under increased N deposition in central Europe, this study was established. Laboratory experiments focused on measurements of the patterns ...
The need for noninvasive sensitive techniques for the diagnosis and follow-up of metabolic bone disease in dialysis patients has stimulated the author's interest in the efficacy of more detailed quantitative bone scintigraphy. Using hemodialysis to reduce elevated soft-tissue activity at scintigraphy, an attempt was made to assess the diagnostic sensitivity of quantitative bone scintigraphy as compared to qualitative bone scintigraphic, biochemical, radiographic and bone histologic studies. The second aim of these studies was to determine if one of the two major components of renal osteodystrophy is a major determinant for skeletal radiotracer uptake. The clinical observations on the efficacy and possible specificity of quantitative bone scintigraphy in the diagnosis and follow-up during treatment of renal osteodystrophy are presented briefly in this chapter. Thus, the use of scintigraphy for the routine detection and ...
Fetal exposure to phthalates may be associated with adverse reproductive effects, including cryptorchidism and decreased semen quality. Information about human placental transfer is needed to qualify the hypotheses. A dual recirculating placenta perfusion system to monitor concentrations of eight phthalate monoesters in fetal and maternal perfusates was established. In addition to perfusate background measures of phthalate monoesters, the concentrations in umbilical cord plasma and placenta tissue were measured. Monomethyl phthalate (mMP), monoethyl phthalate (mEP), monobutyl phthalate (mBP), and mono (2-ethyl-hexyl) phthalate (mEHP) were detected in both maternal and fetal perfusate, demonstrating a release of compounds from tissue or blood to perfusates. The distribution of compounds between perfusate, umbilical cord plasma, and tissue was in accordance with the physical-chemical properties of the compounds. Results from the present study of compounds residing in ...
Summaries are presented for those research contracts which expired between December 31, 1960 and December 31, 1981. Topics covered include: factors controlling distribution of fission products in biosphere, non-destructive methods of evaluating the U/sup 235/ and Pu content of irradiated fuel elements, studies of contamination in local marine resources, tracer studies of anemia, non-destructive analysis of irradiated fuel elements using a flux integrating monitor, mechanism of proteolysis of I/sup 131/-labeled fibrinogen, radiosensitivity of spermatogonia of Drosophila melel elements by gamma scanning, uptake and loss of radioactive material by marine bacteria, factors which influence the movement of radioactive strontium from soils to plants, biological concentration of fission products in mollusks from water, decay scheme of Tl/sup 210/, calcium balance in metabolic bone disease, development of ...
Abstract Neurodegenerative and neurometabolic disorders may cause significant morbidity and mortality in children. Imaging is important in early diagnosis of metabolic disorders and in determining the extent of brain injury. Especially after the development of new techniques such as diffusion-weighted magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS), neuroimaging plays more important role in the diagnosis and management of these disorders. In these disorders, usually a mutation causes a clinically significant block in one or more metabolic pathways. This blockage usually results in either a deficiency of the product or in an accumulation of substrate with damage induced by either storage or toxicity. The presenting symptoms are usually nonspecific. In some of the ...
The central nervous system (CNS), generally accepted to regulate energy homeostasis, has been implicated in the metabolic perturbations that either cause or are associated with obesity. Normally, the CNS receives hormonal, metabolic, and neuronal input to assure adequate energy levels and maintain stable energy homeostasis. Recent evidence also supports that the CNS uses these same inputs to regulate glucose homeostasis and this aspect of CNS regulation also becomes impaired in the face of dietary-induced obesity. This review focuses on the literature surrounding hypothalamic regulation of energy and glucose homeostasis and discusses how dysregulation of this system may contribute to obesity and T2DM.
Understanding the physical characteristics of the local microenvironment in which Mycobacterium tuberculosis resides is an important goal that may allow the targeting of metabolic processes...Full Text Available
A filamentous fungus, Cunninghamella blakesleeana AS 3.153, was used as a microbial model of mammalian metabolism to transform verapamil, a calcium channel antagonist. The metabolites...Full Text Available
A diagnosis of dementia is devastating at any age but diagnosis in younger patients presents a particular challenge. The differential diagnosis is broad as late presentation of metabolic disease...Full Text Available
Dogs challenged with toxic doses of methylsalicylate developed acute myocardiopathy. Metabolic manifestations of uncoupling of oxidative phosphorylation by methylsalicylate (MS) were observed. Oxygen...Full Text Available
High resolution of NMR spectroscopic data of biosamples are a rich source of information on the metabolic response to physiological variation or pathological events. There are many advantages...Full Text Available
Obesity is characterized by the abnormal or excessive deposition of fat in the adipose tissue. Its consequences go far beyond adverse metabolic effects on health, causing an increase in oxidative stress,...Full Text Available
The quest to understand why we age has given rise to numerous lines of investigation that have gradually converged to include metabolic control by mitochondrial activity as a major player. That...Full Text Available
Aging is the most significant risk factor for a range of degenerative disease such as cardiovascular, neurodegenerative and metabolic disorders. While the cause of aging and its associated diseases...Full Text Available
Summary: Analysis of biological networks requires assessing the statistical significance of network-based predictions by using a realistic null model. However, the existing network null model, switch randomization, is unsuitable for metabolic networks, as it does not include physical constraints and generates unrealistic reactions. We present JMassBalance, a tool for mass-balanced randomization and analysis of metabolic networks. The tool allows efficient generation of large sets of randomized networks under the physical constraint of mass balance. In addition, various structural properties of the original and randomized networks can be calculated, facilitating the identification of the salient properties of metabolic networks with a biologically meaningful null model. Availability and Imp...
Much progress has been made in understanding the complex pharmacokinetics of trichloroethylene (TCE). Qualitatively, it is clear that TCE is metabolized to multiple metabolites either locally or into...Full Text Available
MD, Chief, Division of Endocrinology, Diabetes and Metabolism, Trinitas Regional Medical Center, Elizabeth, NJ. Review provided by VeriMed Healthcare Network. Also reviewed...
Francisella tularensis is a Gram-negative bacterium capable of causing the zoonotic disease tularaemia in a large number of mammalian species and in arthropods. F. tularensis...Full Text Available
An elderly man receiving chlorambucil for chronic lymphatic leukaemia developed focal fits. The onset and frequency were dose related. There was no evidence of metabolic disturbance or of meningeal...Full Text Available
Diabetes mellitus is a metabolic disorder that leads to the development of a number of complications. The etiology of each diabetic complication is undoubtedly multifactorial. We will focus...Full Text Available
diet and genetic obesity metabolic defects and inflammation. To determine the role of adipocyte death in promoting adipose tissue inflammation and insulin resistance in animal...
Citrate and lactose fermentation are subject to the same metabolic regulation. In both processes, pyruvate is the key intermediate. Lactococcus lactis subsp. lactis...Full Text Available
The microbial process of converting organic matter into methane and carbon dioxide is so complex that anaerobic digesters have long been treated as {open_quotes}black boxes.{close_quotes} Research into this process during the past few decades has gradually unraveled this complexity, but many questions remain. The major biochemical reactions for forming methane by methanogens are largely understood, and evolutionary studies indicate that these microbes are as different from bacteria as they are from plants and animals. In anaerobic digesters, methanogens are at the terminus of a metabolic web, in which the reactions of myriads of other microbes produce a very limited range of compounds - mainly acetate, hydrogen, and formate - on which the methanogens grow and from which they form methane. {open_quotes}Interspecies hydrogen-transfer{close_quotes} and {open_quotes}interspecies formate-transfer{close_quotes} are major mechanisms by which ...
Elevated fatty acid levels have been thought to contribute to insulin resistance. Repression of the glucose transporter 4 (GLUT4) gene as well as impaired GLUT4 translocation may be a mediator for fatty acid-induced insulin resistance. This study was initiated to determine whether palmitate treatment repressed GLUT4 expression, whether glucose/fatty acid metabolism influenced palmitate-induced GLUT4 gene repression (PIGR), and whether attempts to prevent PIGR restored palmitate-induced impairment of glucose uptake (PIIGU) in C2 myotubes. Not only stimulators of fatty acid oxidation, such as bezafibrate, AICAR, and TOFA, but also TCA cycle substrates, such as pyruvate, leucine/glutamine, and ?-ketoisocaproate/monomethyl succinate, significantly prevented PIGR. In particular, supplementing with pyruvate through methyl pyruvate resulted in nearly complete prevention of PIIGU, whereas palmitate treatment reduced the intracellular pyruvate level. ...
The purpose was to study the toxicity of drugs known to generate free radicals on isolated pancreatic islets. The accumulattion of "8"6Rb"+ by mouse pancreatic islets was measured in vitro. Exposing the islets to 6-hydroxydopamine, minhydrin, or phenazine methosulphate + NADH inhibited the Rb"+ uptake, whereas paraquat or acetylphenylhydrazine had no effect. This effect of 6-hydroxydopamine was prevented by either of the hydroxyl radical scavengers, sodium benzoate and mannitol, but not by the non-scavenger,urea; ninhydrin was partially protected against by mannitol but not by benzoate. Protection against 6-hydroxydopamine was also afforded by D-glucose but not by L-glucose or 3-O-methyl-D-glucose; none of the sugars protected against ninhydrin. In damaging islet beta-cells and in being protected against by D-glucose, 6-hydroxydopamine closely resembles the diabetogenic drug, alloxan. It is suggested that protection against alloxan may involve both glucose ...
Quantitative bone scintigraphy was performed in 24 patients with prostatic carcinoma before orchiectomy and up to one to four years after operation. The gamma camera count rate was recorded over the lower thoracic and all lumbar vertebrae 4 h after injection of [sup 99m]Tc-MDP. Twelve patients has normal bone scintigrams throughout the study. They showed from two years after operation a slight increase in count rate values compared with the preoperative values, probability due to hormonal changes after orchiectomy and to age-related alterations in skeletal metabolism. Twelve patients had abnormal bone scintigrams. They showed as a response to treatment the flare phenomenon with an increase in count rate over the abnormal vertebrae when measured two weeks after operation followed by a decrease after two months. The lowest count rate values were obtained between six months and one year after operation. Thereafter the count rate seemed to remain ...
Quantitative bone scintigraphy was performed in 24 patients with prostatic carcinoma before orchiectomy and up to one to four years after operation. The gamma camera count rate was recorded over the lower thoracic and all lumbar vertebrae 4 h after injection of "9"9"mTc-MDP. Twelve patients has normal bone scintigrams throughout the study. They showed from two years after operation a slight increase in count rate values compared with the preoperative values, probability due to hormonal changes after orchiectomy and to age-related alterations in skeletal metabolism. Twelve patients had abnormal bone scintigrams. They showed as a response to treatment the flare phenomenon with an increase in count rate over the abnormal vertebrae when measured two weeks after operation followed by a decrease after two months. The lowest count rate values were obtained between six months and one year after operation. Thereafter the count rate seemed to remain on ...
Sucrose and mannitol are major photosynthetic products and translocates in celery. Assimilate partitioning and transport were studied by pulse-labeling leaves with /sup 14/CO/sub 2/ followed by different length chases in ambient air. After a 2 h chase in the light there was more /sup 14/C in sucrose than mannitol in source leaves and their petioles. In contrast after a 2 h dark chase leaves contained more /sup 14/C in mannitol than sucrose but petioles had more /sup 14/C in sucrose than mannitol. After a 15 h chase (6 h light; 9 h dark) labeled sucrose was higher in source petiole vascular bundles than in adjacent parenchyma tissue but label in glucose and fructose was higher in the parenchyma tissue. After the 15 h chase most of the /sup 14/C remaining in developing sink leaves and their petioles was in mannitol. Although in the light mannitol:sucrose ratios are the same in leaf and petiole tissues, in the dark sucrose is initially the major translocate with ...
The quantitative estimation of various trace element concentrations in medicinal plants is necessary for determining their effectiveness in treating various diseases and for understanding their pharmacological action. Elemental concentrations of some selected medicinal plants of north east India was measured by proton induced X-ray emission (PIXE) and proton induced {gamma}-ray emission (PIGE) techniques. PIXE measurements were carried out using 2.4 MeV collimated protons from the 3 MV tandetron accelerator of NCCCM, Hyderabad (India) while the PIGE measurements were carried out using 3 MeV protons from the same accelerator in the same laboratory. Accuracy and precision of the techniques were assured by analyzing certified reference materials in the same experimental conditions. Various elements of biological importance in man's metabolism were found to be present in varying concentrations in the studied medicinal plants and no toxic ...
This report briefly describes the studies on the mechanism of in vivo DNA repairing by the author in Research Reactor Institute, Kyoto Univ. for the past 30 years. First, the ability of UV radiation to induce transformation was investigated with viral DNA. The formation of thymine-thymine dimer was found harmful to organisms and such dimers were removable by UV-radiation at a low frequency. The mutability was determined in three different E.coli strains with mutator gene, mutT, mutS or mutL. The ability to excise 8-oxoguanin developed in primer DNA was deficient in mutT and miss-pairing left after DNA replication could not be recovered in mutL and mutS strains. Further, DNA repairing mechanism was investigated in other microorganisms; single-strand cleavage caused by exposure to BNCB radiation (boron-neutron-captured beam) could not be repaired in E. coli. Whereas for Deinococcus radiodurans, of which survival rate was not decreased by #gamma#-ray radiation at 5 ...
3T3 - L1 cells can be induced to differentiate by exposing cell culture to a medium containing 3-isobutyl-1-methyl-xanthine together with insulin and dexamethasone. They have observed that oxalomalate (OMA) which inhibits aconitase thus blocking the citric cycle, also favours differentiation to adipocytes leading to fatty acids accumulation and increased synthesis of specific proteins. They compared the effects of 3-isobutyl-1-methyl-xanthine-insulin-dexamethasone and OMA on the steady-state levels of mRNA of c / EBP, H-ferritin and aconitase / IRE-BP. OMA does not affect the steady-state mRNA amount of C / EBP, H-ferritin and aconitase / IRE-BP but the 3-isobutyl-1-methyl-xanthine-insulin-dexamethasone mixture is able to induce a five-fold increase of mRNA levels for aconitase / IRE-BP. This is the first finding correlating iron metabolism to adipocyte differentiation. Further studies will clarify a possible role for the aconitase inhibitor ...
Cerebral maturation in the human fetal brain was investigated by in utero localized proton magnetic resonance spectroscopy (MRS). Spectra were acquired on a clinical MR system operating at 1.5 T. Body phased array coils (four coils) were used in combination with spinal coils (two coils). The size of the nominal volume of interest (VOI) was 4.5 cm"3 (20 mm x 15 mm x 15 mm). The MRS acquisitions were performed using a spin echo sequence at short and long echo times (TE = 30 ms and 135 ms) with a VOI located within the cerebral hemisphere at the level of the centrum semiovale. A significant reduction in myo-inositol and choline and an increase in N-acetylaspartate were observed with progressive age. The normal MR spectroscopy data reported here will help to determine whether brain metabolism is altered, especially when subtle anatomic changes are observed on conventional images. Some examples of impaired fetal brain development studied by MRS are ...
Ethanol is generally toxic to microorganisms, and intracellular and extracellular accumulation of ethanol inhibits cell growth and metabolism. In this study, pyruvate decarboxylase (pdc) and alcohol dehydrogenase (adhB) were cloned into pET-32a vector and then introduced into E. coli BL21 to produce ethanol. Heat shock genes (BEM1 and SOD2) from Saccharomyces cerevisiae were inserted into recombinant ethanolic E. coli using pET28_a vector to improve ethanol shock resistance. Three different strains were constructed: Ethanolic E. coli (adhB and pdc genes inserted using pET32_a vector), BEM1 gene-inserted E. coli (BEM1 inserted using pET_28a), and SOD2-inserted E. coli (SOD2 inserted using pET28_a). Construction of these three different strains allowed comparison of the functions of these he...
Microbial degradation of aromatic hydrocarbons has been studied with the aim of developing applications for the removal of toxic compounds. Efforts have been directed toward the genetic manipulation of mesophilic bacteria to improve their ability to degrade pollutants, even though many pollution problems occur in sea waters and in effluents of industrial processes which are characterized by low temperatures. From these considerations the idea of engineering a psychrophilic microorganism for the oxidation of aromatic compounds was developed.In a previous paper it was demonstrated that the recombinant Antarctic Pseudoalteromonas haloplanktis TAC125 (PhTAC/tou) expressing a toluene-o-xylene monooxygenase (ToMO) is able to convert several aromatic compounds into corresponding catechols. In our work we improved the metabolic capability of PhTAC/tou cells by combining action of recombinant ToMO enzyme with that of the endogenous P. haloplanktis ...
Arachidonic acid is metabolized by means of P450 isoenzyme(s) to form epoxyeicosatrienoic acids (EETs) and their corresponding dihydroxy derivatives (DHETs). In the present study, we established the presence in human urine of 8,9-, 11,12-, and 14,15-EETs and their corresponding DHETs by developing quantitative assays and using negative ion, chemical ionization GC/MS and octadeuterated internal standards. Urinary excretion of 8,9- and 11,12-DHET increased in healthy pregnant women compared with nonpregnant female volunteers. By contrast, excretion of 11,12-DHET and 14,15-DHET, but not the 8,9-DHET regioisomer, increased even further in patients with pregnancy-induced hypertension. Intravenous administration of (3H)14,15-EET to three dogs markedly increased its DHET in plasma. The terminal half-life ranged from 7.9-12.3 min and the volume of distribution (3.5-5.3 liters) suggested limited distribution outside the plasma compartment. Negligible ...
In 576 patients quantitative scintigraphy of the sacroiliac joints and the spinal cord with "9"9"mTc-pyrophosphate was performed. 328 were patients with proven ankylosing spondylitis according to the New York criteria. 120 were patients with a clinically and roentgenologically suspected ankylosing spondylitis and 128 persons formed a healthy control group. The count rate in small regions of interest (ROI) in the sacroiliac joints, the spinal cord and the os sacrum were compared on the basis of indexes. The scintigraphic data of patients with ankylosing spondylitis were compared with the healthy control group and with the radiographic findings and radiologic staging of the disease. In a longitudinal follow-up study during 1 to 6 years these investigations were continued together with clinical and roentgenological checks. Quantitative bone scintigraphy provides characteristic indexes for ankylosing spondylitis, indicating the increased mineral ...
In general, over the course of the time, the phenomenon of acceleration in physical development may be observed, i.e. the children and adults of the next generation are taller and heavier than in former generation. Our data presented in this paper show a regular trend of acceleration in the development on Vietnamese, but the trend is still slow and was mostly probably influenced by our difficulties in a long time of war. It is hoped that, the acceleration in the development may be increased in the future following the economical acceleration of our country, however it is known that the ratio between the length of different parts of human body is a specific characteristic for human race, sex and group age. Therefore we may estimate these ratio for the prolongation of the utilization of our measured physical data. The result of studies on water balance of Vietnamese living in comfortable environment air temperature conditions and working in hot environment with ...
IntroductionCopper(II)-diacetyl-bis(N4-methylthiosemicarbazone), or Cu-ATSM, a hypoxia imaging agent, has been shown to be predictive of response to traditional cancer therapies in patients with a wide range of tumors. It is known that the environment of the tumor results in a myriad of physiological consequences, including hypoxia, alterations in metabolism and proliferation. In an effort to better characterize the relationships between Cu-ATSM and other prominent radiopharmaceuticals, this current study was undertaken to compare the regional distribution of 64Cu-ATSM with [18F]fluoromisonidazole (18F-FMISO), [18F]fluoro-2-deoxy-d-glucose (18F-FDG) and [18F]fluorothymidine (18F-FLT) in 9L tumors.MethodsTaking advantage of the different half-life of 18F (t1/2=110 min) in comparison to 64Cu...
Background & AimsMolecular mechanisms underlying alcoholic liver disease (ALD) are still not fully understood. Activating transcription factor-4 (ATF4) is the master coordinator of the integrated stress response (ISR), an adaptive pathway triggered by multiple stressors. which can promote cell death and induce metabolic dysregulation if the stress is intense or prolonged. The aim of this study was to assess the effect of alcohol on the ISR signaling pathway in human liver cells and to define the role of cytochrome P450 2E1 (CYP2E1) in this response. MethodsPrimary cultured human hepatocytes and human HepG2 cells over-expressing CYP2E1 by adenoviral infection were exposed to ethanol (25-100mM) for 8-48h. ResultsEthanol treatment of both liver cells up-regulated ATF4 as well as the pro-survi...
The aim of this work was to develop several strategies and software-packages for the evaluation of in-vivo-data of the human brain, which were acquired with high-resolution 1H-MRSI at 1.5 and 3 T. Several studies involving phantoms, volunteers and patients were performed. Quality assurance studies were conducted in order to evaluate the reproducibility of the applied MR-techniques at both field strengths. A qualitative comparison-study between MRSI-data from a 1.5 T clinical MR-scanner and a 3 T research MR-scanner showed the advantages of the more advanced MRSI sequences and higher field strength (3 T). A study involving patients with primary brain tumours (gliomas) was performed in cooperation with the Department of Neurosurgery (University of Erlangen-Nuremberg). The methods developed in the course of this study, such as the integration of MRS-data into a stereotactic-system, the ...
The metabolism of pentose-phosphate was investigated in Plasmodium falciparum-infected normal and glucose-6-phosphate dehydrogenase (G6PD)-deficient human red blood cells in vitro. 5'-Phosphoribosyl-1-pyrophosphate...Full Text Available
The effective half-life based on urine bioassay results of Wolsung NPP's worker was calculated. The effective half-life for tritiated water vapour obtained was 5 {approx} 9 days. In comparison to 10 days reported for ICRP-30, it is lower than the corresponding half-life for Reference Man. Also, the half-life was calculated based on intake amount of daily water. According to this result, the metabolism was reviewed.
SummaryThe transcriptional co-repressor SMRT utilizes two major receptor interacting domains (RID1 and RID2) to mediate nuclear receptor (NR) signaling through epigenetic modification....Full Text Available
Although peroxisome proliferator-activated receptor alpha (PPARα) is closely associated with myocardial fatty acid metabolism, the pathophysiological role of PPARα in myocardial infarction...Full Text Available
Hepatocyte nuclear factor (HNF) 4α is a key transcription factor regulating endo/xenobiotic-metabolizing enzymes and transporters. We investigated whether microRNAs are involved in the regulation...Full Text Available
Metabolism of [14C]gibberellin (GA) A12 (GA12) and [14C]gibberellin A12-aldehyde (GA12-aldehyde) was examined in cotyledons and seed...Full Text Available
Maleic hydrazide (MH) is taken up by corn and pea seedling roots and bound to some material which is insoluble in 80% ethanol or 5% trichloroacetic acid. 14C-MH is stable metabolically; chromatography...Full Text Available
Little is known about how diet and energy metabolism interact in determination of lifespan under ad libitum feeding. From 12 weeks of age until death, male and female wild-type (WT) and transgenic (TG)...Full Text Available
The clinical and metabolic effects of two regimens of total parenteral nutrition delivering the same amino-acid (2·8 g/kig per 24 h), fat (4·8 g/kg per 24 h), and glucose (12 g/kg per...Full Text Available
Transcription activation of sulfur metabolism in yeast is dependent on two DNA binding factors, the centromere binding factor 1 (Cbf1) and Met4. While the role of Met4 was clearly established by showing...Full Text Available
L-[3-"1"8F]-#alpha#-methyltyrosine ("1"8F-FMT) is an amino-acid tracer for positron-emission tomography (PET). We have conducted a clinicopathologic study to elucidate the correlation of angiogenesis with "1"8F-FMT and 2-["1"8F]-fluoro-2-deoxy-D-glucose ("1"8F-FDG) uptake in patients with non-small cell lung cancer (NSCLC). Thirty-seven NSCLC patients were enrolled in this study, and two PET studies with "1"8F-FMT and "1"8F-FDG were performed. Uptake of PET tracers was evaluated with standardized uptake value. Vascular endothelial growth factor (VEGF), CD31, CD34, L-type amino acid transporter 1 (LAT1) and Ki-67 labeling index of the resected tumors were analyzed by immunohistochemical staining, and correlated with the clinicopathologic variables and the uptake of PET tracers. The median VEGF rate was 45% (range, 10-78%). High expression was seen in 30 patients (81%, 30/37). VEGF expression was statistically associated with ...
Laron syndrome (LS) is an autosomal recessively inherited condition characterized by insensitivity to endogenous and exogenous GH. Affected individuals have severe episodes and other characteristic features. GH receptor gene mutations are present in all affected individuals in whom molecular studies have been reported. The GH receptor is a plasma membrane-spanning protein in which the extracellular domain binds circulating GH and the intracellular domain interacts with the JAK-2 kinase and possibly other intracellular signaling molecules. GH receptor dimerization occurs on GH binding and is thought to be required for normal signal transduction. We have studied the GH receptor genes of four unrelated individuals affected with LS from the United States, Italy, Saudi Arabia, and India. We have identified four different missense mutations that alter consecutive amino acids 152 to 155 in or near the dimerization domain of the GH receptor. One of ...
The disruption of primary innate immune function of the epidermal layer of the skin accounts for the susceptibility of individuals using bleaching agents to localized or systemic infections. This subverted innate immunity in these people may lead to other pathological conditions. The resultant effects of skin bleaching and phagocytes activation in response to infections have not been studied in Nigerians using bleaching agents. The present study therefore assessed the levels of C-reactive protein (CRP), albumin, total antioxidant potential (TAP), total plasma peroxides (TPP), oxidative stress index (OSI) and malonaldehyde (MDA) in the users bleaching agents. Thirty (30) people who had used bleaching agents for average of 4.9 + 1.2 years participated in this study. They were recruited from various schools and markets within the city of Ibadan, Oyo State, Nigeria. Thirty apparently healthy staffs of University College ...
Investigations and studies are conducted seeking for a CO2 fixation method improved by utilizing the photosynthesizing function of higher vegetation. Details of higher vegetation genes are being disclosed thanks to the rapid progress of studies making use of molecular biological techniques, and the application of the genetic mechanism to scientific and technological fields is becoming increasingly feasible. In particular, the role of the CO2 fixation enzyme RuBisCO has been elucidated almost completely. It has been learned that, in terms of photosynthesizing capability, the C{sub 4} plants (corn etc.) are 2-3 times higher than the C{sub 3} plants (rice, wheat, etc.), and 5-10 times higher than the CAM plants (cactuses etc.). Studies are also under way about the rice genome so that a photosynthesizing capability so high as that of the C{sub 4} plants may be endowed the rice plant. The metabolism and ...
Previous studies have documented dissimilatory growth of bacteria on solid Mn{sup 4+} oxide, but Mn{sup 3+} oxides have not been previously studied; here the authors have demonstrated for the first time the bacterial reduction of manganite. Strain MR-4 of Shewanella putrefaciens was able to grow on and rapidly reduce insoluble needle-shaped crystals of synthetic manganite (MnOOH), converting them to soluble Mn{sup 2+} in the process. The rate of Mn{sup 3+} reduction was optimal at pH of 7.0 and 26 C consistent with an enzymatic reaction. In addition the rates of reduction were in proportion to the amount of manganite added, but nearly independent of the cell concentration present (e.g., cell number had only a small effect on the rate of Mn{sup 3+} reduction at early stages of growth) suggesting that surface properties were dictating the rates of metal reduction. This thesis was supported by major differences in reduction rates when Mn oxides of ...
Rice is a very important food staple that feeds more than half the world's population. Two major Asian cultivated rice (Oryza sativa L.) subspecies, japonica and indica, show significant phenotypic variation in their stress responses. However, the molecular mechanisms underlying this phenotypic variation are still largely unknown. A common link among different stresses is that they produce an oxidative burst and result in an increase of reactive oxygen species (ROS). In this study, methyl viologen (MV) as a ROS agent was applied to investigate the rice oxidative stress response. We observed that 93-11 (indica) seedlings exhibited leaf senescence with severe lesions under MV treatment compared to Nipponbare (japonica). Whole-genome microarray experiments were conducted, and 1,062 probe sets were identified with gene expression level polymorphisms between the two rice cultivars in addition to differential expression under MV treatment, which were assigned as Core ...
Carotenoids are highly beneficial for human nutrition and health because they provide essential nutrients and important antioxidants in our diets. However, many food crops, especially the major staple crops contain only trace to low amounts of carotenoids. Although significant progress has been made in developing food crops rich in carotenoids by altering the expression of carotenoid biosynthetic genes, in many cases it has proved to be difficult to reach the desired levels of carotenoid enrichment. The recent identification and characterization of a novel gene mutation in cauliflower reveals that creating a metabolic sink to sequester carotenoids is an important mechanism to control carotenoid accumulation in plants. The successful demonstration of increased carotenoid accumulation in ass...
Thirty fattened one humped desert camels were used to examine the effect of season on contractile and metabolic properties of Longissimus thoracis (LT) muscle. Ten camels were slaughtered according to seasons of the year (winter, summer and autumn). Season significantly influenced muscle chemical composition, ultimate pH (pHu) and color. Activities of metabolic enzymes were higher during autumn season compared to summer and winter for phosphofructokinase (+64% compared to both seasons) and for isocitrate dehydrogenase (+35% and +145% in autumn vs. summer and winter, respectively). Quantification of muscle myosin heavy chain isoforms by SDS-PAGE electrophoresis showed only presence of type I and type IIa MyHC in camel muscle and indicated high proportion in winter for type I and in autumn f...
Acidification is one of the most common and serious problems inducing process failure in anaerobic digesters. The production of volatile fatty acids (VFAs) mainly triggers acidic shock. However, little is known about the bacteria involved in the processes of acidogenic metabolism, such as fermentation and reductive acetogenesis. Here, the metabolic responses of a methanogenic community to the acidification and resulting process deterioration were investigated using transcriptional profiling of both the 16S rRNA and formyltetrahydrofolate synthetase (FTHFS) genes. The 16S rRNA-based analyses demonstrated that the dynamic shift of bacterial populations was closely correlated with reactor performance, especially with VFA accumulation levels. The pH drop accompanied by an increase in VFAs stim...
Biotin is an essential water-soluble vitamin crucial for maintaining normal body functions. The importance of biotin for human health has been under-appreciated but there is plenty of opportunity for future research with great importance for human health. Currently, carrying out predictions of biotin metabolism involves tedious manual manipulations. In this paper, we report the development of BiotinNet, an internet based program that uses Bayesian networks to integrate published data on various aspects of biotin metabolism. Users can provide a combination of values on the levels of biotin related metabolites to obtain the predictions on other metabolites that are not specified. As an inherent feature of Bayesian networks, the uncertainty of the prediction is also quantified and reported to...
Circadian rhythms affect several processes in the body physiology. This commentary revisits the topic of `metabolic basis of diseases' with a view to shed light on how cellular energy requirements feed-forward to a sequential signaling of hormonal response, blood glucose metabolism, antioxidant activities, and pathophysiology. Attempt is made to explain how diseases that may not appear to be closely related, such as bone metabolism and vasculopathy, have an increase in oxidative damage as a common underlying biochemistry. Importantly, this article identifies oxidative damage as an outcome of sleep disturbance and hypothesize that sleep complaint is not merely one of many resulting symptoms of PTSD, but a core feature that arise from trauma and gives rise to the stress biochemistry, which i...
The Baird and McGuire site is a former chemical manufacturing facility in northwest Holbrook, Massachusetts, approximately 14 miles south of Boston. From 1912 to 1983 the company operated a chemical manufacturing and batching facility on the property. Manufactured products included herbicides, pesticides, disinfectants, soaps, floor waxes and solvents. Waste disposal methods at the site included direct discharge into the soil, nearby brook and wetlands, and a former gravel pit (now covered) in the eastern portion of the site. EPA conducted a removal action at the site in 1983 after a waste lagoon overflowed spreading contaminants into the Cochato River. The company ceased operating shortly thereafter. A second removal action was conducted in 1985, following the discovery of dioxin in site soils. EPA also conducted an Initial Remedial Measure at the site from 1985 through 1987 which involved constructing a new water main to direct water away from the site, removing building structures, ...
The association of Finnish Plastics Industry examined the possibilities to utilize energy content of plastic wastes in spring 1990. A bark fuelled boiler plant of forest industry was used as test power plant. The power of the plant was 60 Mw. This report discusses shortly the theory of combustion of plastics. About 130 000-15 000 tons of plastic waste, corresponding to 7 % of the solid municipal waste, is dumped annually in Finland. Utilization of the plastic waste recovered from municipal wastes for energy production is technically viable in present power plants among present energy production. The chipping and mixing of the plastic in the other fuel are the only pretreatment required for the plastic waste. In Finland there are several power plants using suitable fuels for plastic mixture combustion. The portion of the plastic of the total fuel power was 10 %. No problems occurred during the tests. The results of the tests are presented in this report. Special attention has been paid ...
A broad range of persistent organic pollutants (POPs) and selected heavy metals has been analysed in sediment cores of North-East Germany. The pollutants analysed include polychlorinated dioxins and furans (PCDD/Fs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), several pesticides (DDT, HCH, CBz) and its metabolites as well as selected heavy metals. The sediment cores were sampled at five locations, reflecting a range of anthropogenic influences and background contamination: Arkona Basin (AK) representing a remote marine site, Lake Bugsin (BS) a background location only with atmospheric deposition, Lake Quenz (QS) close to the industrial city of Brandenburg, Teltowkanal (TK) in the suburban-industrial zone of Berlin and Lake White (WS) in the centre of Berlin. The age of the lower part of the AK, BS and TK cores were dated at 100-150 years. Results of selected pollutants (PCDD/Fs) have been presented earlier, focussing on the depth ...
Positron emission tomography (PET) is a fully quantitative technology for imaging metabolic pathways and dynamic processes in vivo. Attenuation correction of raw PET data is a prerequisite for quantification and is typically based on separate transmission measurements. In PET/CT attenuation correction, however, is performed routinely based on the available CT transmission data. Recently, combined PET/magnetic resonance (MR) has been proposed as a viable alternative to PET/CT. Current concepts of PET/MRI do not include CT-like transmission sources and, therefore, alternative methods of PET attenuation correction must be found. This article reviews existing approaches to MR-based attenuation correction (MR-AC). Most groups have proposed MR-AC algorithms for brain PET studies and more recently also for torso PET/MR imaging. Most MR-AC strategies require the use of complementary MR and transmission images, or morphology templates generated from ...
Autofluorescence spectroscopy has been a widely explored technique for in vivo and noninvasive diagnosis of pre-cancer lesions in epithelium where 90% cancers originate. For extracting more accurate fluorescence information for cancer diagnosis, depth-resolved fluorescence measurements are crucial to assess NADH and FAD in non-keratinized epithelial layer and collagen in stromal layer, respectively. In this study, we achieved the depth-resolved fluorescence spectral measurements of squamous epithelial tissue based on confocal technique. We found that in non-keratinized epithelial layer the fluorescence signals excited at 405 nm were the combination of NADH and FAD fluorescence and could be used for evaluating the redox ratio. Moreover, we found that confocal time-resolved autofluorescence measurements of epithelial tissue with 405 nm excitations could provide the information on the layered tissue structure. All depth-resolved autofluorescence decays were accurately ...
A model of weightlessness in which the hindlimbs of rats are elevated by their tails at a 40 degrees angle to unload the hindlimbs while maintaining normal weight bearing on the forelimbs has been used to simulate certain conditions of space flight. When we used this model in growing rats, we found that growth in bone weight ceased by 1 week in the hindlimbs and lumbar vertebrae, whereas growth in bone weight in the forelimbs and cervical vertebrae remained unaffected. Within 2 weeks, however, the accretion of bone weight in the hindlimbs and lumbar vertebrae returned to normal despite continued skeletal unloading. Since bone weight in the growing rat is primarily determined by bone formation (bone resorption is modest), we investigated the effects of selective skeletal unloading on bone formation during 2 weeks of hindlimb elevation using radioisotope incorporation (with /sup 45/Ca and (/sup 3/H)proline) and histomorphometry (with tetracycline labeling). The ...
Nitroaromatic radiosensitizers become metabolically bound preferentially to hypoxic cells and at least 10/sup 9/ adducts/cell can be tolerated as non-toxic. EMT-6 tumor cells have been incubated in hypoxia in the presence of /sup 3/H-Misonidazole and /sup 125/I-Azomycin Riboside for various times and the amount of /sup 3/H or /sup 125/I bound/cell was determined. Cells were stored as monolayers at 25"0C for up to 96 hr to accumulate radioactive decays and transferred at various times to 37"0C for colony-forming assays. No radiation inactivation was measured in cells which had incorporated at least 10/sup 6/ /sup 3/H or 10/sup 5/ /sup 125/I atoms. Previous studies had shown that -- 1% of MISO adducts to EMT-6 cells was associated with cellular DNA. These data indicate that the radiation-induced damage produced by these quantities of bound /sup 3/H or /sup 125/I causes little or not cell inactivation. The results of current ...
Dual energy X-ray absorptiometry (Hologic QDR-1000) was used to quantitatively analyze the diagnosis and prevention of osteoporosis. The peak bone mineral density (BMD) of the spine appeared in normal men in their twenties and in normal women in their thirties. There was acceleration of bone loss in the 50 to 60 year age bracket (premenopause and postmenopause) in normal women. On the contrary, the peak BMD of the femoral neck in normal men and women appeared in their twenties after which it decreased slightly with age. Comparison showed that the femoral neck BMD of normal women was lower than that of men throughout all ages. The fracture threshold, 0.756 g/cm[sup 2] for the spine, was obtained by scanning 73 females with spinal fractures, the mean BMDs for L2-L4 at the 90th percentile level were used as the fracture threshold. The fracture threshold of femoral neck fracture was the femoral proximal BMD of the 9th decile. Classification by the Public Welfare Silver Science ...
This paper presents a group's efforts to introduce national newborn screening in Lebanon. Tandem mass spectrometry (MS) technology offers the prospect of utilizing filter paper blood specimens to screen newborns for several metabolic disorders. In order to be cost-effective, it is necessary to have a mandatory newborn screening policy. At present such a policy is not available in Lebanon. A national screening survey for congenital hypothyroidism (CH) was carried out to assess the incidence of this anomaly in the Lebanese population. Such an initiative is essential as a first step for assessing the feasibility and cost of a national screening programme. Coated beads, blood spot standards for quality control and buffer solutions used for assays were prepared in-house to minimize costs. At first, samples of umbilical cord blood spots were assayed for TSH using IRMA technique. Those samples showing borderline or high values of TSH were then assayed for total T4 (TT4) ...
High quality "3"1P MR spectra (signal to noise ratio (S/N) approximately 18, 15 min acquisition for each spectrum) were consistently obtained with surface coils over a period of 6-week RT. Both transient and steady state alterations in metabolites in response to RT were found in this case. The transient changes occurred during the first 3 hr immediately after the 3rd fractionated RT, these changes include the transient elevation of the PCr resonance, a decrease in PDE and an increase in intracellular pH. The monitoring showed that the metabolites approached steady state approximately 2 hr after the fractionated radiation intervention, suggesting that in vivo MRS can be useful for studying the dynamics of tumor response to RT such as repair of potential lethal damage, growth delay, and reoxygenation etc. The steady-state MR spectra showed the net response to each intervention and can clinically be useful for predicting and measuring the result of the fractionated ...
To study the regulation of adipose tissue lipoprotein lipase (LPL) in human adipocytes, omental adipose tissue was obtained from healthy subjects and digested in collagenase. The isolated adipocytes thus obtained were suspended in Medium 199 and cultured at 37 degrees C. Cell viability was demonstrated in adipocytes cultured for up to 72 h by constancy of cell number, cell size, trypan-blue exclusion, and specific /sup 125/I-insulin binding. In addition, chloroquine induced an increase in cell-associated /sup 125/I-insulin at 24, 48, and 72 h after preparation. Thus, isolated adipocytes retained their ability to bind, internalize, and degrade insulin. LPL was measured as activity secreted into the culture medium (CM), released from cells by heparin (HR), and extracted from cell digests. A broad range of heparin concentrations produced a prompt release of LPL from a rapidly replenishable pool of cellular activity. When cells were cultured in medium containing 10% ...
Nuclear magnetic resonance is a powerful technique that can be used in a wide range of applications, such as the structural characterization of high molecular weight molecules, conformational studies on enzymes in solution, enzyme-substrate or DNA-protein interactions, monitoring of cell metabolism in vivo, and for diagnostic purposes, employing spectroscopic and imaging techniques. This course was organized in order to introduce the participants to the fundamentals of NMR spectroscopy, and offer practical advice on performing NMR experiments on cell systems, cell and tissue extracts and animal models. The main implications regarding human experiments were also discussed. Finally the quantification of information and the interpretation of data were considered with regard to the main nuclei observed. [Italiano] La risonanza magnetica nucleare e` una delle tecniche spettroscopiche che meglio risponde all`ampio spettro di condizioni imposto dalla ...
(Materials and Methods) (I) VX/sub 2/ carcinoma was transplanted to the rabbit tibia, sup(99m)Tc-MDP was intravenously injected when bone destruction was radiologically seen. Preoperative scintigraphs, postoperative one of the resected tibia and fibra and scintigraphs of sliced tumor were compared with each other. Tissue fragments were collected from the sliced tumor, and RI was measured to compare concentration rates at different parts together with histological investigations. (II) Tetracycline was given to the rabbit of Experiment (I) to compare with the concentration of sup(99m)Tc-MDP. (III) Microautoradiography method was done on the experimental animals for investigation of the concentration of sup(99m)Tc-MDP. (Results) (I) Localization of sup(99m)Tc-MDP was increased at the sites of tumorous bone formation, of reactive bone formation at tumor edges, and of cartilage calcification, with little concentration at tumor cells or necrotic tissue. (II) Deposition sites of tetracycline ...
Incorporation of tritium into body constituent molecules from tritiated water and its in vivo behaviors were studies using rats. In single administration of HTO, "3H behaviors were studied in lipids that are rich in hydrogen. Incorporation of "3H into the lipid fraction from HTO and its release differed by each organ and by the type of lipid components. Of routes of administration, the oral and parenteral routes showed same results, and no prominent difference was noted by inhalation. By consecutive administration, the urine "3H concentration showed no difference according to the route, but increased as the concentration of administered HTO increased. When administration was discontinued after the urine "3H concentration reached a plateau, the biological half-life was about 4.5 days, almost in agreement with the value by single administration. In relation to water intake, increase in the urine volume and accompanying promotion of urine "3H ...
Endocrine disrupting chemicals can induce malformations and impairment of reproductive function in experimental animals and may have similar effects in humans. Recently, the environmental obesogen hypothesis was proposed, suggesting that environmental chemicals contribute to the development of obesity and insulin resistance. These effects could be related to chemical interaction with nuclear receptors such as the peroxisome proliferator activated receptors (PPARs). As several testosterone-reducing drugs are PPAR activators, we aimed to examine whether four PPAR agonists were able to affect fetal testosterone production and masculinization of rats. Additionally, we wished to examine whether these chemicals affected fetal plasma levels of insulin and leptin, which play important roles in the developmental programming of the metabolic system. Pregnant Wistar rats were exposed from gestation day (GD) 7-21 to diisobutyl phthalate (DiBP), butylparaben, ...
Changes in the phosphate metabolism of the transplanted SCCVII (squamous cell carcinoma VII) tumor were studied before and after irradiation using in vivo [sup 31]P-magnetic resonance spectroscopy (MRS). Phosphocreatine (PCr), [gamma]-, [alpha]-, [beta]-ATP, inorganic phosphate (Pi), phosphomonoester (PME), and phosphodiester (PDE) were detected in [sup 31]P-MR spectra of tumor tissues. The curve fitting method was employed for calculating each peak of [sup 31]P-MR spectra (PCr, [beta]-ATP, Pi, PME, PDE). The values of PCr, PCr/Pi, [beta]-ATP/Pi and pH decreased in proportion to the growth of tumor, whereas that of Pi, PME and PDE increased. But the changes of [beta]-ATP were minimal in degree. Based on the fact that the ratio of PCr/Pi highly correlated with tumor volume and showed the most remarkable change among various parameters, it might be the useful index for the tumor growth. Because the phospholipid metabolite PME was detected in the ...
This study is aimed at exploring the possible mechanism of hypnosis-enhancing effect of HgS or cinnabar (a traditional Chinese medicine containing more than 95% HgS) in mice treated with pentobarbital. We also examined whether the effect of HgS is different from that of the well-known methyl mercury (MeHg). After a short period (7 days) of oral administration to mice, a nontoxic dose (0.1 g/kg) of HgS not only significantly enhanced pentobarbital-induced hypnosis but also attenuated tolerance induction; while a higher dose (1 g/kg) of HgS or cinnabar exerted an almost irreversible enhancing effect on pentobarbital-hypnosis similar to that of MeHg (2 mg/kg) tested, which was still effective even after 10 or 35 days cessation of administration. To study comparatively the effects of different mercury forms from oral administration of MeHg and HgS on membrane ATPase activities of experimental mice, analysis of the Hg content in the cerebral cortex ...
Medicinal plants play a major role in the life of Turkish people and of late medicinal plant usage has increased in many countries. Green plants in general contain mutagenic and carcinogenic substances, but there is little information about the biological activities of herbal medicine. In the present study, therefore, various Turkish medicinal herbs were investigated for their genotoxic potential in the Salmonella typhimurium microsomal activation assay and the alkaline single cell gel electrophoresis (COMET) assay. Extracts from these medicinal herbs and some fractions of these extracts were examined. The species investigated were Arctium minus, Ecballium elatterium, Momordica charantia, Plantago major, Urtica dioica, Viscum album, Salvia triloba, Euphorbia rigida, Stachys lavandulifolia, Acteoside, Abies nordmannia. They are used for various immune disorders and are applied either topically or taken orally as a herbal tea. Of the 19 samples of the extracts and ...
Glioblastoma multiforme is the most aggressive form of human brain tumor, which has no effective cure. Previously, we have demonstrated that overexpression of the C-terminal fragment of the human telomerase reverse transcriptase (hTERTC27) inhibits the growth and tumorigenicity of human cervical cancer HeLa cells. In this study, the therapeutic effect and molecular mechanisms of hTERTC27-mediated cancer gene therapy were further explored in vivo in established human glioblastoma xenografts in nude mice. We showed that intratumoral injection of adeno-associated virus carrying hTERTC27 (rAAV-hTERTC27) is highly effective in reducing the growth of the subcutaneously transplanted glioblastoma tumors. Histological analyses showed that rAAV-hTERTC27 treatment leads to profound necrosis, apoptosis, infiltration of polymorphonuclear neutrophils and reduced microvessel density in the tumor samples. To study the molecular mechanism of ...
For terrestrial animals and plants, a fundamental cost of living is water vapor lost to the atmosphere during exchange of metabolic gases. Here, by bringing together previously developed models for...Full Text Available
SummaryBrown fat is specialized in energy expenditure, a process that is principally controlled by the transcriptional co-activator PGC-1α. Here we describe a molecular...Full Text Available
BackgroundTransposons, i.e. transposable elements (TEs), are the major internal spontaneous mutation agents for the variability of eukaryotic genomes. To address the general issue...Full Text Available
Mitochondria and peroxisomes execute some analogous, nonredundant functions including fatty acid oxidation and detoxification of reactive oxygen species, and, in response to select metabolic cues, undergo...Full Text Available
Strong inhibitory effects of the anionic surfactant linear alkylbenzene sulfonate (LAS) on four strains of autotrophic ammonia-oxidizing bacteria (AOB) are reported. Two Nitrosospira...Full Text Available
Sixty-five patients operated with total pancreatectomy were reviewed with respect to factors influencing operative mortality and morbidity, long-term survival, and metabolic sequelae. The diagnoses...Full Text Available
Purpose of ReviewThe vertebrate cap’n’collar family transcription factor Nrf2 and its invertebrate homologs SKN-1 (in worms) and CncC (in flies) function...Full Text Available
Disposable nappies (diapers) have been satisfactorily demineralized and used for the collection of excreta from infants and young children during mineral and trace metal balances. It was possible to...Full Text Available
Reactive oxygen species (ROS), inevitable byproducts of aerobic metabolism, are known to cause oxidative damage to cells and molecules. This, in turn, is widely accepted as a pivotal determinant of...Full Text Available
1. γ-Hexachlorocyclohexane, γ-pentachlorocyclohexene and δ-pentachlorocyclohexene were converted by houseflies and grass grubs into metabolites that had chromatographic properties...Full Text Available
Peripheral subunit binding domains (PSBDs) are integral parts of large multienzyme complexes involved in carbohydrate metabolism. PSBDs facilitate shuttling of prosthetic groups between different catalytic...Full Text Available
The effect of thiamin on the organ distribution of lead was evaluated in CD-1 mice exposed intragastrically or intraperitoneally to a single dose of lead acetate (100 micrograms) containing 100 microCi...Full Text Available
The metabolism of DDT has been followed in pure lines of laboratory-reared resistant and susceptible anophelines using gas-liquid chromatography. Relatively large amounts of DDE were formed in...Full Text Available
Before the influence of divergent factors on gross efficiency (GE) [the ratio of mechanical power output (PO) to metabolic power input (PI)] can be assessed, the variation in GE between days, i.e. the...Full Text Available
Many of the gene products that participate in nitrogen metabolism are sensitive to nitrogen catabolite repression (NCR), i.e., their expression is decreased to low levels when readily used nitrogen...Full Text Available
Thyroid hormone is a critical regulator of growth, development and metabolism in virtually all tissues, and altered thyroid status affects many organs and systems. Although for many years testis...Full Text Available
BackgroundThe pregnane X receptor (PXR; NR1I2), a member of the nuclear receptor superfamily, regulates the expression of metabolic enzymes and transporters involved...Full Text Available
When the detached first leaves of green or etiolated oat (Avena sativa cv. Victory) seedlings senesce in the dark, their oxygen consumption shows a large increase, beginning after 24...Full Text Available
Disorders of mitochondrial fat metabolism lead to sudden death in infants and children. Although survival is possible, the underlying molecular mechanisms which enable this outcome have not yet been...Full Text Available
Experiments were carried out to clarify problems encountered in measuring metabolic and storage pool sizes of nitrate in wheat leaf sections with an in vivo nitrate reductase assay....Full Text Available
SummarySoluble epoxide hydrolase (sEH) is a key enzyme in the metabolic conversion and degradation of P450 eicosanoids called epoxyeicosatrienoic acids (EETs). Genetic variations...Full Text Available
In vivo short-term effects of recombinant human TNF-alpha on lipolysis, FFA flux, fat oxidation, triglyceride-fatty acid cycling, and glucose kinetics were evaluated with stable isotopic tracers and...Full Text Available
BackgroundCurrently used indicators of iron status have limitations. Hepcidin, a key regulator of iron metabolism, is reduced in iron deficiency. We sought to determine the properties...Full Text Available
The subfornical organ is a major receptor area for one of the principal stimuli of thirst, the octapeptide, angiotensin II. In conscious water-sated rats, the authors examined the effects of intravenous infusion of angiotensin II on the rate of glucose utilization in the subfornical organ and in structures anatomically and functionally connected with it. Angiotensin II produced pressor and drinking responses and increased glucose utilization selectively in the subfornical organ and pituitary neural lobe and in no other brain structure. Treatment with the angiotensin II antagonist, sar1-leu8-angiotensin II, before intravenous administration of angiotensin II prevented metabolic stimulation of the subfornical organ and neural lobe. Captopril, an inhibitor of angiotensin-converting enzyme, reduced subfornical organ glucose metabolism to a level similar to that found in control animals. These results demonstrate that peripheral angiotensin II ...
Hibernators are unique among mammals in their ability to survive extended periods of time with core body temperatures near freezing and with dramatically reduced heart, respiratory, and metabolic rates...Full Text Available
The levels of glucose, sugar phosphates, and adenosine phosphates were determined in primary leaves of intact bean plants during normal senescence and compared to leaves in which senescence was delayed...Full Text Available
Phospho-beta-galactosidase (P-beta-gal), the enzyme which catalyzes the first step in the metabolism of intracellular lactose phosphate, occurred at high specific activity in the cytoplasm in 12 of...Full Text Available
The prevalence of obesity among children, adolescents and adults has been dramatically increasing worldwide during the last several decades. The obesity epidemic has been recognized as one of...Full Text Available
The measurement of physiological parameters in man is possible with the help of positron emission tomography (PET) and radiopharmaceuticals labeled with short lived positron emitters as C 11, N 13, O 15 and F 18. With the use of this substances it is possible to make a tomographic map defining regional metabolic parameters in normal and diseased brain. This technique has therefore also be named 'in vivo autoradiography'. The possibility of applying C 11 or F 18 labeled deoxyglucose with PET for detecting regional and local changes in cerebral metabolic rate of glucose in brain development in children of 5 days to 1 year of age is discussed. Beyond this a relationship between cerebral metabolic rate of glucose, cerebral blood flow and cerebral metabolic rate of oxygen by use of this technique after inhalation of O 15 and C 11-labeled CO_2 is shown. Attention is drawn to the application of C ...
When oxygen is limiting, animals can ferment glucose via several metabolic pathways varying in energetic efficiency and leading to various end products (such as lactate, succinate, or propionate). Because the pH dependence of H/sup +/ production by fermentation is opposite to that by hydrolysis of adenosine triphosphate formed in the fermentation, the total number of moles of protons generated is always two per mole of fermentable substrate. However, two and three times more adenosine triphosphate can be turned over per mole of protons produced in succinate and propionate fermentations, respectively, than in lactate fermentation. At its limit, this advantage would achieve the same balance between H/sup +/ production and H/sup +/ consumption during ATP cycling that is observed in aerobic metabolism, a situation observed in certain alcohol fermentations. Since proton balance during anaerobiosis is clearly adaptable, we consider possible impact ...
The parathyroid hormone receptor (PTHR) is a class B G protein-coupled receptor that plays critical roles in bone and mineral ion metabolism. Ligand binding to the PTHR involves interactions to both...Full Text Available
The osmoprotectant Pro betaine is the main betaine identified in alfalfa (Medicago sativa). We have investigated the long-term responses of nodulated alfalfa plants to salt stress,...Full Text Available
OBJECTIVENicotinamide adenine dinucleotides (NAD+ and NADH) play a crucial role in cellular energy metabolism, and a dysregulated NAD+-to-NADH ratio is implicated...Full Text Available
BackgroundIn Saccharomyces cerevisiae galactose is initially metabolized through the Leloir pathway after which glucose 6-phosphate enters glycolysis. Galactose...Full Text Available
SummaryPAS domains sense oxygen, redox potential and light, and are implicated in behavior, circadian rhythmicity, development and metabolic regulation. Although PAS domains are...Full Text Available
While specific signalling cascades involved in aging, such as the insulin/IGF-1 pathway, are well-described, the actual metabolic changes they elicit to prolong lifespan remain obscure. Nevertheless,...Full Text Available
Mucopolysaccharidosis type IIIB (MPS IIIB; Sanfilippo syndrome type B) is a metabolic disorder with devastating clinical characteristics starting in early childhood and leading to premature death. A...Full Text Available
IntroductionSeizures with or without trauma may cause fractures that occur commonly in epileptic seizures. Fracture risk is less reported in non-epileptic seizures. Some metabolic...Full Text Available
The polarity of biological mediums controls a host of physiological processes such as digestion, signaling, transportation, metabolism, and excretion. With the recent widespread use of near-infrared...Full Text Available
BackgroundMutations that impair mitochondrial functioning are associated with a variety of metabolic and age-related disorders. A barrier to rigorous tests of the role of mitochondrial...Full Text Available
The response of the dissimilatory metal-reducing bacterium Shewanella alga BrY to carbon and nitrogen starvation was examined. Starvation resulted in a gradual decrease in the mean cell volume from...Full Text Available
Microorganisms in the environment can often adapt to use xenobiotic chemicals as novel growth and energy substrates. Specialized enzyme systems and metabolic pathways for the degradation of man-made...Full Text Available
1. The LD50 of iodomethane orally administered to rats is 76mg./kg. body wt. but repeated daily doses of 30–50mg./kg. body wt. are without effect. 2. Oral doses of iodomethane to...Full Text Available
Over the last three to four decades, it has been observed that the average total hours of sleep have decreased to less than seven hours per person per night. Concomitantly, global figures relating to...Full Text Available
Poly(3-hydroxyalkanoates) (PHAs) are a class of microbially produced polyesters that have potential applications as conventional plastics, specifically thermoplastic elastomers. A wealth of biological...Full Text Available
l-Ribulose is a rare and expensive sugar that can be used as a precursor for the production of other rare sugars of high market value such as l-ribose. In this work we describe a production...Full Text Available
Sources of manganese are identified. Uptake and distribution of manganese in plants and man are discussed, and the role of manganese in metabolism is described. The epidemiology of manganese toxicity is outlined, permissible air concentrations are listed, and the symptoms of manganese toxicity and deficiency are described. 555 references, 32 tables.
Obesity and metabolic syndrome result from excess calorie intake and genetic predisposition and are mechanistically linked to type II diabetes and accelerated body aging; abnormal nutrient and insulin...Full Text Available
Sirtuins are highly conserved NAD+-dependent protein deacetylases and/or ADP-ribosyltransferases that can extend the lifespan of several lower model organisms including yeast, worms and flies....Full Text Available
Iron is a central element in the metabolism of normal and malignant cells. Abnormalities in iron and ferritin expression have been observed in many types of cancer. Interest in characterizing iron compounds...Full Text Available
BackgroundMacrophages (MΦs) utilize macropinocytosis to integrate immune and metabolic signals in order to initiate an effective immune response. Diabetes is characterized...Full Text Available
... hepatopancreas (1.55 ppm), gonad (5.18 ppm), epithelial tissue (6.17 ppm) and, most significantly, the eyestalks ( ... by Day 1 Stage I larvae and by epithelial tissue of postmolt juvenile lobsters. Postmo...
Nitric oxide (NO) and related reactive nitrogen species (RNS) play a major role in the pathophysiology of stroke and other neurodegenerative diseases. One of the poorly understood consequences...Full Text Available
Two isoenzymes each of phosphoglucomutase, hexose phosphate isomerase, aldolase, fructose diphosphatase, phosphofructokinase, and 6-phosphogluconate dehydrogenase have been separated by DEAE-cellulose...Full Text Available
A strain of Neurospora crassa was isolated by training the mould to grow on media containing high concentrations of Co2+. This strain, the CoR strain, exhibited...Full Text Available
The cytokine interleukin-7 (IL-7) has essential growth activities that maintain the homeostatic balance of the immune system. Little is known of the mechanism by which IL-7 signaling regulates metabolic...Full Text Available
We present a software system that computationally reproduces biochemical radioisotope-tracer experiments. It consists of three main components: A mapping database of substrate-product atomic correspondents...Full Text Available
BackgroundIn chordates, retinoid metabolism is an important target of short-chain dehydrogenases/reductases (SDRs). It is not known whether SDRs play a role in retinoid...Full Text Available
Growth of Lactococcus lactis subsp. lactis biovar diacetylactis was observed on media with citrate as the only energy source. At pH 5.6, steady state was achieved in...Full Text Available
Quantitative probing of heterogeneous regions in muscle is feasible with phosphorus-31 magnetic resonance spectroscopy because of the differentiation of metabolic patterns of glycolytic and oxidative...Full Text Available
Parasitic nematodes cause serious diseases in humans, animals, and plants. They have limited lipid metabolism and are reliant on lipid-binding proteins to acquire these metabolites from their hosts....Full Text Available
Little is known about the metabolic origin of petroselinic acid (18:1 delta 6cis), the principal fatty acid of the seed oil of most Umbelliferae, Araliaceae, and Garryaceae species. To examine the possibility...Full Text Available
Metabolic profiling analyses were performed to determine metabolite temporal dynamics associated with the induction of acquired thermotolerance in response to heat shock and acquired freezing tolerance...Full Text Available
Isolated cauliflower (Brassica oleracea) bud plastids, purified by isopycnic centrifugation in density gradients of Percoll, were found to be highly intact, to be practically devoid...Full Text Available
The aromas of fruits, vegetables, and flowers are mixtures of volatile metabolites, often present in parts per billion levels or less. We show here that tomato (Lycopersicon esculentum...Full Text Available
Obesity is a risk factor for stroke and neurodegenerative disease. Excess body fat has been linked to impaired glucose metabolism, insulin resistance, and impulsivity and may be a precursor to decline...Full Text Available
Investigations of enzymes involved in DNA metabolism have strongly benefited from the establishment of single molecule techniques. These experiments frequently require elaborate DNA substrates, which...Full Text Available
Bitter orange (Citrus aurantium) extract is widely used in dietary supplements for weight management and sports performance. Its primary protoalkaloid is p-synephrine....Full Text Available
Mice lacking acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1), an enzyme that catalyzes the terminal step in triacylglycerol synthesis, have enhanced insulin sensitivity and are protected from...Full Text Available
The effects of temperature on rates of cellulose synthesis, respiration, and long-term glucose uptake were investigated using cultured cotton ovules (Gossypium hirsutum L. cv Acala...Full Text Available
The hypothesis, that a decrease in metabolic rate mediates the life span prolonging effect of caloric restriction (CR), was tested using two strains of mice, one of which, C57BL/6, exhibits...Full Text Available
Increasing attention is being paid to the scientific evaluation of traditional Chinese medicine (TCM). As many TCMs are capable of biotransformation in the gastrointestinal tract, attention to biotransformation...Full Text Available
Social stress is prevalent in many facets of modern society. Epidemiological data suggest that stress is linked to the development of overweight, obesity and metabolic disease. Although there...Full Text Available
Sialic acids are structurally unique nine-carbon keto sugars occupying the interface between the host and commensal or pathogenic microorganisms. An important function of host sialic acid is to regulate...Full Text Available
We have isolated a second gene (MLS1), which in addition to DAL7, encodes malate synthase from S. cerevisiae. Expression of the two genes is specific for their physiological roles in carbon and nitrogen...Full Text Available
The enzyme 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase in Drosophila melanogaster synthesizes mevalonate for the production of nonsterol isoprenoids, which are essential for growth and...Full Text Available
Proteins that metabolize or bind the nucleotide second messenger cyclic diguanylate regulate a wide variety of important processes in bacteria. These processes include motility, biofilm formation, cell...Full Text Available
Objective: Creatine and phosphocreatine (PCr) are important compounds in the normal energy metabolism of muscle. Recently, it has been shown that dietary creatine (5 to 20 g/day)...Full Text Available
Species of the large family Orchidaceae display a spectacular array of adaptations and rapid speciations that are linked to several innovative features, including specialized pollination syndromes,...Full Text Available
Activation of beta-adrenergic or muscarinic acetylcholine receptors expressed in transfected cells or epidermal growth factor receptors in human keratinocytes produces 15% to 200% changes in cellular...Full Text Available
Diabetic pregnancies are characterized by chronic metabolic insults, including iron deficiency, that place the developing brain at risk and for memory impairment later in life. A behavioral...Full Text Available
A mesophilic yeast, Candida utilis, and a psychrophilic yeast, Leucosporidium stokesii, were subjected to freeze-thaw cycling over the range 25 to -60 C. Viability...Full Text Available
The ability to adapt and respond to nutrients is an ancient cellular function, conserved from unicellular to the most complex multicellular organisms, including mammals. Mammals adapt to changes...Full Text Available
Pesticide chemicals are an important component of modern agriculture. Through their use, plants and animals are exposed to pesticides directly and indirectly from transport through soil, water, and...Full Text Available
Carbohydrate/citrate cometabolism in Lactococcus lactis results in the formation of the flavor compound acetoin. Resting cells of strain IL1403(pFL3) rapidly consumed citrate while...Full Text Available
Social opportunities and work demands have caused humans to become increasingly active during the late evening hours, leading to a shift from the predominantly diurnal lifestyle of our ancestors...Full Text Available
In the growing chloronema cell suspension cultures of the moss Funaria hygrometrica Hedw., activities of several enzymes have been found to be cell-density-dependent. Cyclic nucleotide...Full Text Available
Tyrosinase or polyphenol oxidase (EC 1.14.18.1) is the key enzyme in melanin biosynthesis and in the enzymatic browning of fruits and vegetables. The role of tyrosinase in the secondary metabolism of...Full Text Available
Exogenously supplied indole-3-acetic acid (IAA) stimulated ethylene production in tobacco (Nicotiana glauca) leaf discs but not in those of sugar beet (Beta vulgaris...Full Text Available
Cortical bone contributes the majority of overall bone mass and bears the bulk of axial loads in the peripheral skeleton. Bone metabolic disorders often are manifested by cortical microstructural changes...Full Text Available
BackgroundAdipose tissue lipid storage and processing capacity can be a key factor for obesity-related metabolic disorders such as insulin resistance and diabetes. Lipid uptake is...Full Text Available
Adipocyte death has been reported in both obese humans and rodents. However, its role in metabolic disorders, including insulin resistance, hepatic steatosis, and inflammation associated with obesity...Full Text Available
Abs facilitate humoral immunity via the classical mechanisms of opsonization, complement activation, Ab-dependent cellular cytotoxicity, and toxin/viral neutralization. There is also evidence that some...Full Text Available
AMP-activated protein kinase (AMPK) is a key regulator of energy metabolism; its activity is regulated by a plethora of physiological conditions, exercises and many anti-diabetic drugs. Recent...Full Text Available
Siderophores are essential factors for iron (Fe) acquisition in bacteria during colonization and infection of eukaryotic hosts, which restrain iron access through iron-binding protein, such as lactoferrin...Full Text Available
BackgroundThe pH is an important parameter controlling many metabolic and signalling pathways in living cells. Recombinant fluorescent pH indicators (pHluorins) have come into vogue...Full Text Available
The interaction of long-chain fatty acids with cells is important for their uptake and metabolism, as well as their involvement in signalling processes. The majority of long-chain fatty acids circulating...Full Text Available
The biosynthetic costs of phenylpropanoid-derived condensed tannins (CTs) and phenolic glycosides (PGs) are substantial. However, despite reports of negative correlations between leaf phenolic content...Full Text Available
Assessment of the regulation of plant metabolism by the calcium ion requires a knowledge of its intracellular levels and dynamics. Technical problems have prevented direct measurement of the concentration...Full Text Available
There is increasing concern for the potential adverse health effects of human exposures to chemical mixtures. To better understand the complex interactions of chemicals within a mixture, it is essential...Full Text Available
The liver is a primary target of growth hormone (GH). GH signals are mediated by the transcription factor signal transducer and activator of transcription 5 (STAT5). Here, we focus on recent discoveries about the role of GH-STAT5 signaling in hepatic physiology and pathophysiology. We discuss roles of the GH-STAT5 axis in body growth, lipid metabolism, and the cell cycle pertaining to hepatosteatosis, fibrosis, and hepatocellular carcinoma. Finally, we discuss recent discoveries about the role of GH-STAT5 in sex-specific gene expression and bile acid, steroid, and drug metabolism.
Microorganisms are ubiquitous in subsurface environments although their populations sizes and metabolic activities can vary considerably depending on energy and nutrient inputs. As a result of their metabolic activities and the chemical properties of their cell surfaces and the exopolymers they produce, microorganisms can directly or indirectly facilitate the biotransformation of radionuclides, thus altering their solubility and overall fate and transport in the environment. Although biosorption to cell surfaces and exopolymers can be an important factor modifying the solubility of some radionuclides under specific conditions, oxidation state is often considered the single most important factor controlling their speciation and, therefore, environmental behavior.
Exposure of the freshwater field crab Barytelphusa guerini to a sublethal concentration of NaF (30 mg litre(-1)) caused significant alterations in protein metabolism. After an exposure time of 15 days, the crab was found to have a marked depletion of total protein and free amino acid content. A significant elevation in transaminases, Aspartate aminotransferase (AAT) and Alanine aminotransferase (ALAT), and Glutamate dehydrogenase (GDH) activities was reflected in the free amino acid levels of the tissues. PMID:15092215
In the present study, the immunomodulatory effect of {beta}-endorphin ({beta}-E) and shorter pro-opiomelancortin (POMC) fragments was evaluated by assessing their influence on respiratory burst in human polymorphonuclear leukocytes (PMN). The effect of the peptides on phorbol myristate acetate (PMA)-stimulated production of reactive oxygen metabolites was measured in a lucigenin-enhanced chemiluminescence (CL) assay. Both POMC peptides with opiate-like activity and their non-opioid derivatives were tested. With the exception of {alpha}-E, PMA-stimulated respiratory burst was suppressed by all POMC fragments tested. A U-shaped dose-response relation was observed. Doses lower than 10{sup {minus}17}M and higher than 10{sup {minus}8}M were without effect. {beta}-E and dT{beta}E both suppressed PMA-induced oxidative burst in human PMN at physiological concentrations. {gamma}-E and dT{gamma}E proved to be less potent inhibitors, reaching maximal effect at higher ...
Endurance-trained older men have a higher proportion of lean tissue and greater muscle cell oxidative capacity, reversing age-related trends and suggesting major changes in protein metabolism. In this study, protein turnover was determined in 6 middle-aged (52+/-1 yr) men who were well trained (VO_2 max 55.2+/-5.0 ml O_2/kg.min) and lean (body fat 18.9+/-2.8%, muscle mass 36.6+/-0.6%). The maintained habitual exercise while consuming 0.6, 0.9 or 1.2 g protein/kg.day for 10-day periods. N flux was measured from "1"5N in urea after oral "1"5N-glycine administration. Myofibrillar protein breakdown was estimated from urinary 3-methyl-histidine. Dietary protein had no effect on turnover rates, even when N balance was negative. Whole body protein synthesis was 3.60+/-0.12 g/kg.day and breakdown was 3.40+/-0.14 g/kg.day for all N intakes. Whole body protein flux, synthesis and breakdown were similar to values reported for sedentary young (SY) or ...
The response of Desulfovibrio vulgaris Hildenborough (DvH),a sulphate-reducing bacterium, to nitrate stress was examined usingquantitative proteomic analysis. DvH was stressed with 105 m M sodiumnitrate(NaNO3), a level that caused a 50 percent inhibition in growth.The protein profile of stressed cells was compared with that of cellsgrown in the absence of nitrate using the iTRAQ peptide labellingstrategy and tandem liquid chromatography separation coupled with massspectrometry (quadrupoletime-of-flight) detection. A total of 737 uniqueproteins were identified by two or more peptides, representing 22 percentof the total DvH proteome and spanning every functional category. Theresults indicate that this was a mild stress, as proteins involved incentral metabolism and the sulphate reduction pathway were unperturbed.Proteins involved in the nitrate reduction pathway increased. Increasesseen in transport systems for proline, glycine^ betaineandglutamateindicate that the ...
The penetrance of Leber's hereditary optic neuropathy (LHON) in families with primary mitochondrial DNA (mtDNA) mutations is very complex. Matrilineal and nuclear genetic background, as well as environmental factors, have been reported to be involved in different affected pedigrees. Here we describe two large Chinese families that show a striking difference in the penetrance of LHON, in which 53.3% and 15.0% of members were affected (P < 0.02), respectively. Analysis of the complete mtDNA genome of the two families revealed the presence of the primary mutation G11778A and several other variants suggesting the same haplogroup status G2a. The family with higher penetrance contained a previously described secondary mutation G13708A, which presents a polymorphism in normal Chinese samples and does not affect in vivo mitochondrial oxidative metabolism as described in a previous study. Evolutionary analysis failed to indicate any ...
The penetrance of Leber's hereditary optic neuropathy (LHON) in families with primary mitochondrial DNA (mtDNA) mutations is very complex. Matrilineal and nuclear genetic background, as well as environmental factors, have been reported to be involved in different affected pedigrees. Here we describe two large Chinese families that show a striking difference in the penetrance of LHON, in which 53.3% and 15.0% of members were affected (P < 0.02), respectively. Analysis of the complete mtDNA genome of the two families revealed the presence of the primary mutation G11778A and several other variants suggesting the same haplogroup status G2a. The family with higher penetrance contained a previously described secondary mutation G13708A, which presents a polymorphism in normal Chinese samples and does not affect in vivo mitochondrial oxidative metabolism as described in a previous study. Evolutionary analysis failed to indicate any putatively ...
Diethyldithiocarbamate (DDTC), a chelating agent, is an active metabolite of disulfiram (Antabus) and is used in the rubber industry. The effect of DDTC on the tissue distribution of "2"0"3Pb was studied in rats. Two groups of rats were given an i.v. injection of 100 #mu#Ci "2"0"3Pb (28.6 nmol/kg b.wt.) as lead acetate. After 10 min one group received 2 mmol/kg b.wt. of DDTC as an i.p. injection. Rats were killed 4 and 72 h after injection of "2"0"3Pb and tissue concentration and excretion of "2"0"3Pb was determined by gamma counting. The brain concentration of "2"0"3Pb in DDTC-treated rats was nine times higher than in controls after 4 h and 14 times higher after 72 h. Treatment with DDTC also increased the lead concentration in fat about seven times at both survival intervals. On the other hand, uptake of "2"0"3Pb in bone was reduced by treatment with DDTC and at 4 h also kidney and blood had a lower concentration of "2"0"3Pb in DDTC-treated rats compared to ...
PPARgamma agonists have been proposed to exert more than metabolic benefits, particularly by anti-inflammatory mechanisms. We hypothesized that pioglitazone might modulate inflammatory and vascular responses to lipopolysaccharide (LPS). In a placebo-controlled parallel-group study in 18 healthy male subjects, the E. coli endotoxin model of inflammation (20 IU/kg i. v.) was employed to test the effect of 60 mg pioglitazone over nine days on inflammatory cytokines. Macrovascular function and microvascular blood flow were assessed by brachial artery ultrasound and retinal blood flow parameters, respectively. Pioglitazone increased brachial artery diameter by 5.6% but had no effect on other outcome parameters under resting conditions. LPS increased cytokine levels to peak concentrations of 91.3+/-22.5 ng/ml (IL-6), 261.4+/-60.0 ng/ml (TNFalpha), and 524.5+/-15.3 ng/ml (VCAM-1). The endotoxin caused microvascular vasodilation and increased retinal ...
A method for the introduction of N-(/sup 3/H)acetyl groups into glycosaminoglycans is described. The procedure is based on (/sup 3/H)acetylation of N-unsubstituted hexosamine residues by treating the polysaccharides with (/sup 3/H)acetic anhydride. Preparations of heparin and heparin sulfate were found to contain significant numbers of N-unsubstituted hexosamine residues, as isolates. In contrast, such units could not be detected in chondroitin sulfate, dermatan sulfate, or hyaluronic acid. These polysaccharides were therefore subjected to partial N-deacetylation by reaction with hydrazine in the presence of hydrazine sulfate. After treatment with (/sup 3/H)acetic anhydride, the specific activities of the resulting labeled polysaccharide preparations ranged between 0.1 X 10/sup 6/ and 0.6 X 10/sup 6/ cpm /sup 3/H/..mu..g of uronic acid. The /sup 3/H-labeled polysaccharide preparations did not differ significantly from the corresponding unlabeled starting materials with regard to ...
Simulation and experimental results on the transport of microbes and nutrients in one-dimensional cores are presented, and the development of a three-dimensional, three-phase, multiple-component numerical model to describe the microbial transport and oil recovery in porous media is described. The change of rock's wettability and associated relative permeability values after microbial treatments were accounted for in the model for additional oil recovery. Porosity and permeability reductions due to cell clogging have been considered and the production of gas by microbial metabolism has been incorporated. Governing equations for microbial and nutrient transport are coupled with continuity and flow equations under conditions appropriate for a black oil reservoir. The computer simulator has been used to determine the effects of various transport parameters on microbial transport phenomena. The model can accurately describe the observed transport of microbes, ...
Simulation and experimental results on the transport of microbes and nutrients in one-dimensional cores are presented, and the development of a three-dimensional, three-phase, multiple-component numerical model to describe the microbial transport and oil recovery in porous media is described. The change of rock`s wettability and associated relative permeability values after microbial treatments were accounted for in the model for additional oil recovery. Porosity and permeability reductions due to cell clogging have been considered and the production of gas by microbial metabolism has been incorporated. Governing equations for microbial and nutrient transport are coupled with continuity and flow equations under conditions appropriate for a black oil reservoir. The computer simulator has been used to determine the effects of various transport parameters on microbial transport phenomena. The model can accurately describe the observed transport of microbes, nutrients, ...
The Nuclear Regulatory Commission stipulates in 10 CFR 61 that disposed low-level radioactive waste (LLW) be stabilized. To provide guidance to disposal vendors and nuclear station waste generators for implementing those requirements, the NRC developed the Technical Position on Waste Form, Revision 1. That document details a specified set of recommended testing procedures and criteria, including several tests for determining the biodegradation properties of waste forms. Cement has been widely used to solidify LLW; however, the resulting waste forms are sometimes susceptible to failure due to the actions of waste constituents, stress, and environment. The purpose of this research program is to develop modified microbial degradation test procedures that will be more appropriate than the existing procedures for evaluating the effects of microbiologically influenced chemical attack on cement-solidified LLW. Groups of microorganisms indigenous to LLW disposal sites are being employed that ...
The Nuclear Regulatory Commission stipulates in 10 CFR 61 that disposed low-level radioactive waste (LLW) be stabilized. To provide guidance to disposal vendors and nuclear station waste generators for implementing those requirements, the NRC developed the Technical Position on Waste Form, Revision 1. That document details a specified set of recommended testing procedures and criteria, including several tests for determining the biodegradation properties of waste forms. Information has been presented by a number of researchers, which indicated that those tests may be inappropriate for examining microbial degradation of cement-solidified LLW. Cement has been widely used to solidify LLW; however, the resulting waste forms are sometimes susceptible to failure due to the actions of waste constituents, stress, and environment. The purpose of this research program was to develop modified microbial degradation test procedures that would be more appropriate than the existing procedures for ...
The effects of a daily 3-g supplement of betaine on kinetic aspects of L-[2H3-methyl-1-13C]methionine (MET) metabolism in healthy young adult men were explored. Four groups of four subjects each were given a control diet, based on an L-amino acid mixture supplying 29.5 and 21.9 mg.kg-1.d-1 of L-methionine and L-cystine for 4 d before the tracer study, conducted on day 5 during the fed state. Two groups received the control diet and two groups received the betaine supplement. Tracer was given intravenously (iv) or orally. The transmethylation rate of MET (TM), homocysteine remethylation (RM), and oxidation of methionine were estimated from plasma methionine labeling and 13C enrichment of expired air. RM tended to increase (P = 0.14) but the TM and methionine oxidation were significantly (P less than 0.05) higher after betaine supplementation when estimated with the oral tracer. No differences were detected with the intravenous tracer. Methionine ...
Objectives: To minimize movement artifacts during tracer imaging studies, the animals are generally sedated. Although many reports describe the effect of barbiturates on brain function, less is published about the general impact on the extracerebral metabolism and tracer biodistribution. This report describes the influence of pentobarbital on tumor uptake of ["1"2"3I]-2-iodo-L-phenylalanine (["1"2"3I]-2I-L-PA) using dissection and nuclear imaging. Methods: R1M tumor-bearing athymic mice were divided into two populations: untreated and pentobarbital-treated. Each group was subjected to dynamic and static planar imaging and organ dissection after ["1"2"3I]-2I-L-PA injection. Two-compartment blood modeling was performed. Analysis of variance (ANOVA), t test and clustered boxplot analyses were used to compare the results between the treatment groups and between the data acquisition methods. Results: Two-compartment blood modeling demonstrated that ...
The role of dietary calcium and phosphorus in modifying the intestinal absorption of lead and also the effect of lead ingestion on the metabolism of cholecalciferol were studied in chicks. The efficiency of absorption of /sup 203/Pb and /sup 47/Ca was increased when the animals were fed a low calcium diet and treated with cholecalciferol. The synthesis of the vitamin D-induced calcium-binding protein (CaBP) was correspondingly increased. When the chicks were depleted of vitamin D and repleted with 1,25-dihydroxycholecalciferol (1,25(OH)/sub 2/D/sub 3/) as their only source of the vitamin, the absorption of both /sup 47/Ca and /sup 203/Pb was unaffected by dietary calcium levels, and no change in CaBP levels occurred. Low dietary intake of phosphorus resulted in an increase in /sup 47/Ca and /sup 203/Pb absorption and in CaBP synthesis when the animals were treated with cholecalciferol. However, when the birds were repleted with 1,25(OH)/sub ...
The role of dietary calcium and phosphorus in modifying the intestinal absorption of lead and also the effect of lead ingestion on the metabolism of cholecalciferol were studied in chicks. The efficiency of absorption of "2"0"3Pb and "4"7Ca was increased when the animals were fed a low calcium diet and treated with cholecalciferol. The synthesis of the vitamin D-induced calcium-binding protein (CaBP) was correspondingly increased. When the chicks were depleted of vitamin D and repleted with 1,25-dihydroxycholecalciferol [1,25(OH)_2D_3] as their only source of the vitamin, the absorption of both "4"7Ca and "2"0"3Pb was unaffected by dietary calcium levels, and no change in CaBP levels occurred. Low dietary intake of phosphorus resulted in an increase in "4"7Ca and "2"0"3Pb absorption and in CaBP synthesis when the animals were treated with cholecalciferol. However, when the birds were repleted with 1,25(OH)_2D_3, the intestinal absorption of ...
We tested the hypothesis that insulin-dependent diabetic patients with coronary artery bypass graft surgery experience altered coupling of cerebral blood flow and oxygen consumption. In a study of 23 patients (11 diabetics and 12 age-matched controls), cerebral blood flow was measured using 133Xe clearance during nonpulsatile, alpha-stat blood gas managed cardiopulmonary bypass at the conditions of hypothermia and normothermia. In diabetic patients, the cerebral blood flow at 26.6 +/- 2.42 degrees C was 25.3 +/- 14.34 ml/100 g/min and at 36.9 +/- 0.58 degrees C it was 27.3 +/- 7.40 ml/100 g/min (p = NS). The control patients increased cerebral blood flow from 20.7 +/- 6.78 ml/100 g/min at 28.4 +/- 2.81 degrees C to 37.6 +/- 8.81 ml/100 g/min at 36.5 +/- 0.45 degrees C (p less than or equal to 0.005). The oxygen consumption was calculated from jugular bulb effluent and increased from hypothermic values of 0.52 +/- 0.20 ml/100 g/min in diabetics to 1.26 +/- 0.28 ...
Untreated landfill leachates and wastes from metal plating and mining operations are sources of environmental contamination by heavy metals. Because of their toxicity and potential for accumulation, the discharge of heavy metals must be controlled. Standard physical and chemical treatments used to remove metals from wastes such as concentration by electro-precipitation, ion exchange, solvent extraction, evaporative recovery, and conventional precipitation, are usually expensive and produce high quantities of sludge. Biosorption is the removal of metals from aqueous solutions by microorganisms. It is called biosorption rather than bioadsorption or bioaccumulation because the mechanisms of removal are not restricted to adsorption or metabolic uptake and so the more general term is preferable and has come to be accepted. In this thesis the focus is one two microorganisms and two metals. However, the possible combinations of conditions such as pH, relative metal ...
The effect of prenatal cimetidine exposure (PreCM) on the duration of pentobarbital-induced narcosis (DPN) was assessed in immature (14- and 28-day old) and adult (50-60-day old) male and female rats. PreCM exposure was accomplished by treating mothers with cimetidine (CM) (20 mg/kg, ip) daily for the last two days of gestation and then (0.01% in drinking water) throughout lactation. Pregnant mothers of untreated offspring (Con) received saline. PreCM decreased DPN to 505 +/- 33 min (from 611 +/- 23 min in Con) and 393 +/- 190 min (from 686 +/- 44 min in Con) in 14-day old male and female rats, respectively. Similarly, PreCM decreased DPN to 88 +/- 15 min (from 134 +/- 3 min in Con) and 102 +/- 19 min (from 171 +/- 44 min in Con) in 28-day old male and female rats, respectively. At 21 days, PreCM did not alter DPN in either sex. At 50-60 days, however, it decreased DPN to 144 +/- 41 min (from 238 +/- 7 min in Con) in females but had no effect in males; PreCM also increased the plasma ...
Background. Metabolic disturbances such as anoxia and hypoglycaemia are important in causing maldevelopment of the neonatal brain. While there have been some pathology studies of the effects of neonatal hypoglycaemia on brain development, reports of MRI findings in such infants have been rare. Objectives. To describe the MRI findings in neurologically handicapped children who had suffered from neonatal hypoglycaemia and to evaluate the relationship between the neurological impairment and neonatal hypoglycaemia. Materials and methods. We retrospectively evaluated the MRI findings in eight full-term infants with neonatal symptomatic hypoglycaemia who later exhibited neurological handicap. The age at which the MRI scans were obtained ranged from 9 months to 8 years 10 months (mean 4 years 1 month, median 4 years). Results. The most striking findings were prolonged T1 weighting and T2 weighting in the parieto-occipital periventricular deep white ...
Macrocephaly was defined as a head measuring larger than 98th percentile. We have evaluated CT findings and head growth curves in 25 infants with large heads. Ten (40%) of 25 infants with large heads were normal developmentally and neurologically. Five (20%) of those were mentally retarded. The other 10 infants (40%) included hydrocephalus (4 cases), malformation syndrome (3 cases), brain tumor (1 case), metabolic disorder (1 case) and degenerative disorder (1 case). Their head growth curves were typed as (I), (II) and (III): Type (I) (excessive head growth curve to 2 SDs above normal); Type (II) (head growth curve gradually approached to 2 SDs above normal); Type (III) (head growth curve parallel to 2 SDs above normal). Ten of macrocephaly with normal psychomotor development were studied clinically and radiologically in details. They were all male. CT pictures of those showed normal or various abnormal findings: ventricular dilatations, wide ...
Investigations of radionuclide metabolism and effects in various mammalian species revealed important similarities between animals and humans and between some animal species. These include skeletal deposition of radium and radiostrontium in bone volume; deposition on bone surfaces of plutonium and other actinides; liver deposition of actinides; induction of skeletal or liver malignancies by these radionuclides; induction of tooth and jaw abnormalities; mammary cancer induction by radium in humans and in the beagle; depression of circulating cells in blood; and induction of bone fractures. There are also inter-species differences that may not have been noted if multiple species (including humans) had not been studied. Some of these are more rapid excretion of radium in humans compared with most other mammals; induction by radium of eye melanomas in animals but not humans; rapid loss of deposited plutonium from liver in many species of mice and ...
1-Furan-2-yl-3-pyridin-2-yl-propenone (FPP-3) is an anti-inflammatory agent with a propenone moiety and chemically synthesized recently. In this study, we examined the chemopreventive effect of FPP-3 on 7,12-dimethylbenz[a]anthracene (DMBA)-induced genotoxicity in MCF-7 cells. FPP-3 reduced the formation of the DMBA-DNA adduct. DMBA-induced CYP1A1 and CYP1B1 gene expression and enzyme activity were inhibited by FPP-3. It inhibited DMBA-induced aryl hydrocarbon receptor (AhR) transactivation and DMBA-inducible nuclear localization of the AhR. Induction of detoxifying phase II genes by chemopreventive agents represents a coordinated protective response against oxidative stress and neoplastic effects of carcinogens. Transcription factor NF-E2 related factor 2 (Nrf2) regulates antioxidant response element (ARE) of phase II detoxifying and antioxidant enzymes, such as glutathione S-transferase (GST) and NAD(P)H:quinone oxidoreductase (QR). FPP-3 increased the expression ...
The three main objectives of this study were: (1) to determine if depletion of proteoglycans from the cartilage matrix that occurs during osteoarthritis causes a measurable increase of cartilage proteoglycan components in the synovial fluid and sera, (2) to observe what effect intracellular cAMP has on the expression of matrix components by chondrocytes, and (3) to determine if freshly isolated chondrocytes contain detectable levels of mRNA for fibronectin. Canine serum keratan sulfate and hyaluronate were measured to determine if there was an elevation of these serum glycosaminoglycans in a canine model of osteoarthritis. A single intra-articular injection of chymopapain into a shoulder joint increased serum keratan sulfate 10 fold and hyaluronate less than 2 fold in 24 hours. Keratan sulfate concentrations in synovial fluids of dogs about one year old were unrelated to the presence of spontaneous cartilage degeneration in the joints. High keratan sulfate in ...
Studies investigated whether changes in omega- and (omega-1)-hydroxylation (OH) of lauric acid (LA) occurred in renal microsomes prepared from SHR compared to Wistar-Kyoto (WK) control rats. Systolic blood pressure in age-matched adult SHR and WKR were 189 +/- 3 and 123 +/- 4 mm Hg(anti X +/- SE) respectively (p < 0.001). No significant differences between SHR and WKR were seen in body weight, kidney weight or renal microsomal protein content. Renal microsomes, prepared from whole kidneys, were incubated with 10 mM NADPH and ["1"4C]LA at concentrations between 5-50 #mu#M. The 11- and 12-OH metabolites of LA were separated by HPLC using a reverse phase column with a methanol:water:acetic acid (62:37.8:0.2) mobile phase. Apparent (app) V/sub max/ values for 12-OH in WKR and SHR were 0.87 +/- 0.19 vs 1.48 +/- .11 nmoles/mg protein/min (p < 0.05), respectively, while values for 11-OH were 0.51 +/- 0.12 vs 0.60 +/- .07, respectively. No significant differences ...
This paper aims at the study of the transfer and accumulation of "1"0"6Ru from marine foods to man through the grazing food chain and evaluation of the radiation exposure to man. As a model, accumulation and excretion of "1"0"6Ru in mice orally administered by the meat of prawn (Penaeus japonicus) which accumulated the radionuclide from the sea water, were examined and compared with those in mice administered by non-radioactive prawn meat mixed with the contaminant in inorganic chemical forms (the control diet); on the latter experiment, the previous evaluation method of the radiation exposure was based. Higher concentrations of "1"0"6Ru in tissues and organs of mice were observed in the former diet than in the latter because of the higher absorption rate of "1"0"6Ru from the gastrointestinal tract (17.4 +- 4.4%, the control diet: 0.7 +- 0.7%) and smaller excretion. As the results of this experiment, the critical organs for men by ingestion of such a meat should be ...
Hydrolyzates of tissues that had been labeled with (14C)proline often contain significant amounts of cis-4-hydroxy(14C)proline. Since animal cells do not contain an enzyme which can effect formation of cis-4-hydroxyproline, there are only two possible explanations for its presence. Either it is formed during acid hydrolysis of trans-4-hydroxyproline (which is synthesized by cells and is a common constituent of connective tissues), or it is produced by a nonenzymatic mechanism such as attack by oxygen radicals. It is important to resolve this issue because if a nonenzymatic mechanism is active in connective tissues, then it will be necessary to reevaluate currently accepted ideas about production of hydroxyproline. This communication describes a method for distinguishing between the two alternate explanations. Tissues or cells are labeled with (14C)proline, and then a known amount of trans-4-hydroxy(3H)proline is added to each sample before hydrolysis; the relative amounts of (14C)- and ...
Hydrolyzates of tissues that had been labeled with [14C]proline often contain significant amounts of cis-4-hydroxy[14C]proline. Since animal cells do not contain an enzyme which can effect formation of cis-4-hydroxyproline, there are only two possible explanations for its presence. Either it is formed during acid hydrolysis of trans-4-hydroxyproline (which is synthesized by cells and is a common constituent of connective tissues), or it is produced by a nonenzymatic mechanism such as attack by oxygen radicals. It is important to resolve this issue because if a nonenzymatic mechanism is active in connective tissues, then it will be necessary to reevaluate currently accepted ideas about production of hydroxyproline. This communication describes a method for distinguishing between the two alternate explanations. Tissues or cells are labeled with [14C]proline, and then a known amount of trans-4-hydroxy[3H]proline is added to each sample before hydrolysis; the relative amounts of [14C]- and ...
The important role of thyroid hormones in growth and development, maintenance of body temperature, digestion, cardiac function, and normal brain development can be disrupted by environmental contaminants like polychlorinated biphenyls (PCB). Polychlorinated biphenyls are environmental contaminants that are widespread, persistent, lipophilic, and bioaccumulate through food webs, concentrating in adipose tissue. Placental and lactational PCB exposure of offspring causes metabolic and endocrine disruptions including hypothyroxinemia, spatial learning and memory deficits, neurochemical and neurobehavioral alterations, and reproductive problems. Previous studies in our lab using the individual congeners PCB 47 (2,2',4,4'-tetrachlorobiphenyl, ortho-substituted) and PCB 77 (3,3',4,4'-tetrachlorobiphenyl, non-ortho-substituted) have demonstrated alterations in thyroid hormone levels, alterations in brain choline acetyltransferase (ChAT) activity, and ...
Metabolic profile is an important biological marker of neoplastic processes not only in the tumor itself but also in the host organism. The neuro-hormone melatonin has been implicated in the experiments as an oncostatic agent. Female Wistar:Han SPF rats (Velaz, Prague, Czech Republic) were irradiated continuously for 15 days using a daily gamma rays dose of 96 mGy. At the end of exposure one group of rats was administered 5 mg/kg b.w. of dimethylbenz/a/anthracene (DMBA) intragastrically. During the period of exposure to ionizing radiation a part of the animals was supplied with melatonin (M) at a concentration of 20 #mu#l/ml in drinking water. Selected parameters of lipid and carbohydrate metabolism and levels of selected hormones were determined 2, 30 and 100 days post-irradiation. The irradiation itself caused only small changes in tissue lipids. The application of a single low dose (subthreshold from the point of view of induction of mammary ...
Urinary acidification, bone metabolism and urinary excretion of calcium and citrate were evaluated in 10 recurrent stone formers with incomplete renal tubular acidosis (iRTA), 10 recurrent stone formers with normal urinary acidification (NUA) and 10 normal controls (NC). Patients with iRTA had lower plasma standard bicarbonate after fasting (P <0.01) and lower urinary excretion of titratable acid (P <0.05) and citrate (P <0.01) compared with NUA patients and NC, and higher urinary excretion of ammonia (P <0.05) compared with NC (P <0.05). Hypercalciuria was found in 6 of 10 patients with iRTA compared with 3 of 10 with NUA, and 0 of 10 NC. The citrate/calcium ratio in urine was significantly reduced in iRTA compared with the value in NUA (P <0.01), and in NUA compared with NC (P <0.05). Biochemical markers of bone formation (serum osteocalcin) and bone resorption (urinary hydroxyproline) were significantly increased in iRTA compared with NUA ...
Production of hydrogen sulfide in produced waters due to the activity of sulfate-reducing bacteria (SRB) is a potentially serious problem. The hydrogen sulfide is not only a safety and environmental concern, it also contributes to corrosion, solids formation, a reduction in produced oil and gas values, and limitations on water discharge. Waters produced from seawater-flooded reservoirs typically contain all of the nutrients required to support SRB metabolism. Surface processing facilities provide a favorable environment in which SRB flourish, converting water-borne nutrients into biomass and H{sub 2}S. This paper will present results from a field trial in which a new technology for the biochemical control of SRB metabolism was successfully applied. A slip stream of water downstream of separators on a produced water handling facility was routed through a bioreactor in a side-steam device where microbial growth was allowed to develop fully. This ...
l-Carnitine is a critical metabolite indispensable for the metabolism of lipids as it facilitates fatty acid transport into the mitochondrion where b-oxidation occurs. Human astrocytes (CCF-STTG1 cells) and hepatocytes (HepG2 cells) exposed to aluminum (Al) and hydrogen peroxide (H2O2), were characterized with lower levels of l-carnitine, diminished b-oxidation, and increased lipid accumulation compared to the controls. g-Butyrobetainealdehyde dehydrogenase (BADH) and butyrobetaine dioxygenase (BBDOX), two key enzymes mediating the biogenesis of l-carnitine, were sharply reduced during Al and H2O2 challenge. Exposure of the Al and H2O2-treated cells to a-ketoglutarate (KG), led to the recovery of l-carnitine production with the concomitant reduction in ROS levels. It appears that the chann...
Recycling of carbon by the photorespiratory pathway involves enzymatic steps in the chloroplast, mitochondria, and peroxisomes. Most of these reactions are essential for plants growing under ambient CO2 concentrations. However, some disruptions of photorespiratory metabolism cause subtle phenotypes in plants grown in air. For example, Arabidopsis thaliana lacking both of the peroxisomal malate dehydrogenase genes (pmdh1pmdh2) or hydroxypyruvate reductase (hpr1) are viable in air and have rates of photosynthesis only slightly lower than wild-type plants. To investigate how disruption of the peroxisomal reduction of hydroxypyruvate to glycerate influences photorespiratory carbon metabolism we analyzed leaf gas exchange in A. thaliana plants lacking peroxisomal HPR1 expression. In addition, b...
Background In chordates, retinoid metabolism is an important target of short-chain dehydrogenases/reductases (SDRs). It is not known whether SDRs play a role in retinoid metabolism of protostomes, such as Drosophila melanogaster. Methods Drosophila genome was searched for genes encoding proteins with ?50% identity to human retinol dehydrogenase 12 (RDH12). The corresponding proteins were expressed in Sf9 cells and biochemically characterized. Their phylogenetic relationships were analyzed using PHYLIP software. Results A total of six Drosophila SDR genes were identified. Five of these genes are clustered on chromosome 2 and one is located on chromosome X. The deduced proteins are 300 to 406 amino acids long and are associated with microsomal membranes. They recognize all-trans-retinaldehyd...
An experiment lasting a number of hours was carried out with 6 men under standardised climate chamber conditions to find out to what extent wallpaper that reflects about 65-75% in the infra-red range by comparison with normal wallpaper that reflect only 3-5% of heat, has measurable positive effects on the thermoregulation of the human body and the human sensation of temperature. The measurements of skin temperature and heat flow intensity in the deeper areas of the body and the periphery, and metabolic heat conversion measurements (indirect calorimetry) confirm that infra-red reflection of the heat irradiated from the body lead to a measurable heat recovery on the body surface with a reduction of metabolic conversion. It was proved that it is possible to reduce the average room temperature by up to 4 K whilst maintaining the same degree of thermal comfort, which corresponds to a 20% saving in heating energy. (orig./BWI).
Hydrogen cyanide (HCN) production by Pseudomonas aeruginosa in a synthetic medium is stimulated by the presence of glycine. Methionine enhances this stimulation but will not substitute for glycine as a stimulator of cyanogenesis. Threonine and phenylalanine are effective substitutes for glycine in the stimulation of HCN production. Glycine, threonine, and serine are good radioisotope precursors of HCN, but methionine and phenylalanine are not. Cell extracts of P. aeruginosa convert (/sup 14/C)threonine to (/sup 14/C)glycine. H14CN is produced with low dilution of label from either (1-/sup 14/C)glycine or (2-/sup 14/C)glycine, indicating a randomization of label either in the primary or secondary metabolism of glycine. When whole cells were fed (1,2-/sup 14/C)glycine, cyanide and bicarbonate were the only radioactive extracellular products observed.
Obesity is associated with increased susceptibility to dyslipidemia, insulin resistance, and hypertension, a combination of traits that comprise the traditional definition of the metabolic syndrome. Recent evidence suggests that obesity is also associated with the development of nonalcoholic fatty liver disease (NAFLD). Despite the high prevalence of obesity and its related conditions, their etiologies and pathophysiology remains unknown. Both genetic and environmental factors contribute to the development of obesity and NAFLD. Previous genetic analysis of high-fat, diet-induced obesity in C57BL/6J (B6) and A/J male mice using a panel of B6-ChrA/J/NaJ chromosome substitution strains (CSSs) demonstrated that 17 CSSs conferred resistance to high-fat, diet-induced obesity. One of these CSS st...
The moment analysis of pulse responses was applied to a biological activated carbon (BAC) bed to evaluate the microbial activity. Glucose and activated carbon fiber (ACF) were employed in experiments as a model tracer and an activated carbon respectively. No significant difference in biodegradation rates of glucose by microorganisms attached on different solid supports such as activated carbon inactivated carbon and glass fibers was observed. However, higher microbial activity was obtained from microorganisms supported on the ACF in terms of the apparent degradation of total organic including metabolic byproducts by microorganisms, since part of the metabolic byproducts was irreversibly deposited onto the ACF. 11 refs., 6 figs.
We have developed a cell-mediated mutagenesis assay in which cells with the appropriate markers for mutagenesis are co-cultivated with either lethally irradiated rodent embryonic cells that can metabolize carcinogenic hydrocarbons or with primary rat liver cells that can metabolize chemicals carcinogenic to the liver. During co-cultivation, the reactive metabolites of the procarcinogen appear to be transmitted to the mutable cells and induce mutations in them. Assays of this type make it possible to demonstrate a relationship between carcinogenic potency of the chemicals and their ability to induce mutations in mammalian cells. In addition, by simultaneously comparing the frequencies of transformation and mutation induced in normal diploid hamster cells by benzo(a)pyrene (BP) and one of its metabolites, it is possible to estimate the genetic target size for cell transformation in vitro.
Glucose homeostasis requires the tight regulation of glucose utilization by liver, muscle and white or brown fat, and glucose production and release in the blood by liver. The major goal of maintaining glycemia at -5 mM is to ensure a sufficient flux of glucose to the brain, which depends mostly on this nutrient as a source of metabolic energy. This homeostatic process is controlled by hormones, mainly glucagon and insulin, and by autonomic nervous activities that control the metabolic state of liver, muscle and fat tissue but also the secretory activity of the endocrine pancreas. Activation or inhibition of the sympathetic or parasympathetic branches of the autonomic nervous systems are controlled by glucose-excited or glucose-inhibited neurons located at different anatomical sites, mainl...
Cadmium is an environmental toxic metal implicated in human diseases. The mechanism of its toxicity is not fully understood. Therefore, the role of cadmium in renal toxicity, and the protective role of selenium against this toxicity were investigated. Forty-five male rats were used through out the study and divided into three groups of 15. The first group received saline solution daily for 10 days. The second group, received cadmium chloride (CdCl_2) (2 mg/kg body weight) intraperitoneally daily for a period of 10 days. The third group, received sodium selenite (1 mg/kg body weight, twice a day) and CdCl_2 (once a day) for a period of 10 days. The results showed that cadmium treatment increased renal lipid peroxidation (measured as malondialdehyde, MDA) which was associated with a significant decrease in the antioxidant systems such as reduced glutathione levels and the activities of glutathione peroxidase (GPx) and thioredoxin reductase (TrxR). On the other hand, ...
This report documents the results of a project funded by DoD's Strategic Environmental Research and Development Program (SERDP) on the science behind development of predictive models for soot emission from gas turbine engines. Measurements of soot formation were performed in laminar flat premixed flames and turbulent non-premixed jet flames at 1 atm pressure and in turbulent liquid spray flames under representative conditions for takeoff in a gas turbine engine. The laminar flames and open jet flames used both ethylene and a prevaporized JP-8 surrogate fuel composed of n-dodecane and m-xylene. The pressurized turbulent jet flame measurements used the JP-8 surrogate fuel and compared its combustion and sooting characteristics to a world-average JP-8 fuel sample. The pressurized jet flame measurements demonstrated that the surrogate was representative of JP-8, with a somewhat higher tendency to soot formation. The premixed flame measurements revealed that flame temperature has a ...
Embryos of chicken (Gallus domesticus), domestic duck (Anas platyrhynchos), and common eider duck (Somateria mollissima) were exposed in ovo to PCBs and to polycyclic aromatic hydrocarbons. Two coplanar PCBs, 3,3{prime},4,4{prime}-tetrachlorobiphenyl (PCB {number_sign}77) and 3,3{prime},4,4{prime},5-pentachlorobiphenyl (PCB {number_sign}126), were considerably more lethal and potent as inducers of 7-ethoxyresorufin O-deethylase (EROD) in chicken embryos (Gallus domesticus) than in embryos of the other two species. In chicken embryos, these compounds caused edema and eye and beak deformities. An artificial mixture of 18 PAHs which all have been detected in environmental samples, was slightly more toxic to embryos of the domestic duck and the common eider duck than to chicken embryos. The most potent compound in the mixture was benzo(k)fluoranthene. When chicken embryo livers were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in vitro, EROD was induced by ...
The overall goal of the DOE fine particulate program is to ensure that the best science and technology is available for any regulatory decision-making related to the health and environmental impacts of ambient fine particulate matter and regional haze. Interest primarily lies in the particulate fraction having aerodynamic diameters of 2.5 microns and less (PM2.5). Particulates of this size are the focus of the newly established National Ambient Air Quality Standards. As such, the Federal Energy Technology Center (FETC) is establishing a fine particulate sampling station at the Center's Pittsburgh site located in South Park Township, PA. This sampling station is one of a group of stations scattered throughout Pennsylvania, West Virginia, and Ohio that constitute the Upper Ohio River Valley Project. The station is equipped with a full complement of fine particulate and gaseous monitors including the following: (1) R and P Sequential FRM sampler, (2) Grimm PM2.5 continuous ...
In June 1997, the US Navy plans to close its Naval Air Facility on Sand Island and transfer the atoll to the US Fish and Wildlife Service for use as a National Wildlife Refuge. Midway provides breeding and feeding habitat for migratory seabirds, terrestrial and marine mammals, sea turtles and other reptiles, and a variety of reef fishes and invertebrates. As part of the base closure and transfer process, 36 sites of potential environmental concern were identified on Sand and Eastern islands. These sites include landfills and uncontrolled disposal areas, hazardous materials storage areas, abandoned transformers, sewer outfalls, and other potential hazardous waste sites. Potential contaminants include pesticides, PAHs, PCBs, and heavy metals. A screening ecological risk assessment was performed at each site with a goal of determining whether contaminants could pose any current or future risks to protected migratory bird or marine mammal wildlife species. Specific ...
Glucose metabolism through glycolysis and hexosamine pathway has been shown to be altered in type 2 diabetes. However, its fate through the pentose phosphate pathway (PPP) is currently unclear....Full Text Available
NADP:malic enzyme from corn (Zea mays L.) leaves was purified by conventional techniques to apparent homogeneity as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis....Full Text Available
This project (a) demonstrated specific dopamine transporter (DAT) uptake in vivo and metabolic stability of a radiolabelled cycloplentadieny rhenium compound in rats and baboons, (b) showed that cyclopentadieny tricarbonyl rhenium and technetium compounds conjugated tropanel could be made by metal transfer with ferrocenes; and (c) explored new methods of synthesizing these compounds under mild conditions.
The coupling between cerebral metabolic rate of oxygen (CMRO2) and blood flow (CBF) in response to visual stimulation was evaluated by means of a model of oxygen delivery. The model predicted a nonlinear relationship between stimulus-evoked changes of oxygen consumption and blood flow. The magnitude of the CMRO2/CBF ratio index (IO2) was used to indicate the degree of flow-metabolism coupling prevailing in specific areas of the brain during physiological stimulation. Therefore, the index provided a measure of the blood oxygenation level dependent (BOLD) magnetic resonance contrast. To evaluate the changes of IO2 in response to visual stimulation, the model was applied to the effect of a changing flicker rate of a visual stimulus on the magnitudes of CBF, CMRO2, and oxygen diffusion capacity, in the human brain. Positron emission tomography (PET) was used to measure the CBF and the CMRO2 in 12 healthy volunteers who viewed a cross-hair ...
A comparative test in mice for pulmonary toxicity between butylated hydroxytoluene (2,6-di-tert.-butyl-4-methylphenol, BHT) and 2,6-di-tert.-butyl-4-(alpha, alpha, alpha-2H3)methylphenol (BHT-d3) showed a significantly lower toxic potency of the latter. The rate of in vitro BHT metabolism to 2,6-di-tert.-butyl-4-methylene-2,5-cyclohexadienone (BHT-QM) was slowed by deuterating BHT in the 4-methyl group. On the other hand, the rate of in vitro metabolism to 2,6-di-tert.-butyl-4-hydroxy-4-methyl-2,5-cyclohexadienone (BHT-OH) was increased with the deuteration. A similar isotope effect of the deuterium substitution on the in vivo metabolic rates of BHT was observed. These observations support the concept that the lung damage caused by BHT is mediated by BHT-QM. The pulmonary toxicity of 2-tert.-butyl-4-ethylphenol (4-EP) and their deuterated analogs was also compared. 2-tert.-Butyl-4-(1,1-2H2)ethylphenol (4-EP-d2) showed a ...
Rice, the world's major staple crop, is a poor source of essential micronutrients, including folates (vitamin B9). We report folate biofortification of rice seeds achieved by overexpressing two Arabidopsis thaliana genes of the pterin and para-aminobenzoate branches of the folate biosynthetic pathway from a single locus. We obtained a maximal enhancement as high as 100 times above wild type, with 100 g of polished raw grains containing up to four times the adult daily folate requirement.
Barley (Hordeum vulgare L. cv Golden Promise) plants were grown in a continuous culture system in which the root and shoot ammonia and amino acid levels were constant over a 6-hour...Full Text Available