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Iranian Journal of Environmental Health... Dec 2012The contamination of groundwater by heavy metal ions around a lead and zinc plant has been studied. As a case study groundwater contamination in Bonab Industrial Estate...
The contamination of groundwater by heavy metal ions around a lead and zinc plant has been studied. As a case study groundwater contamination in Bonab Industrial Estate (Zanjan-Iran) for iron, cobalt, nickel, copper, zinc, cadmium and lead content was investigated using differential pulse polarography (DPP). Although, cobalt, copper and zinc were found correspondingly in 47.8%, 100.0%, and 100.0% of the samples, they did not contain these metals above their maximum contaminant levels (MCLs). Cadmium was detected in 65.2% of the samples and 17.4% of them were polluted by this metal. All samples contained detectable levels of lead and iron with 8.7% and 13.0% of the samples higher than their MCLs. Nickel was also found in 78.3% of the samples, out of which 8.7% were polluted. In general, the results revealed the contamination of groundwater sources in the studied zone. The higher health risks are related to lead, nickel, and cadmium ions. Multivariate statistical techniques were applied for interpreting the experimental data and giving a description for the sources. The data analysis showed correlations and similarities between investigated heavy metals and helps to classify these ion groups. Cluster analysis identified five clusters among the studied heavy metals. Cluster 1 consisted of Pb, Cu, and cluster 3 included Cd, Fe; also each of the elements Zn, Co and Ni was located in groups with single member. The same results were obtained by factor analysis. Statistical investigations revealed that anthropogenic factors and notably lead and zinc plant and pedo-geochemical pollution sources are influencing water quality in the studied area.
PubMed: 23369182
DOI: 10.1186/1735-2746-9-29 -
Determination of the food dye carmine in milk and candy products by differential pulse polarography.Journal of Food and Drug Analysis Sep 2014As a basis for the development of a sensitive analytical method for the determination of carmine food dye, a study of the differential pulse polarographic reduction of...
As a basis for the development of a sensitive analytical method for the determination of carmine food dye, a study of the differential pulse polarographic reduction of carminic acid (CA) on a dropping mercury electrode was performed. For the analytical differential pulse polarographic method running at pH 2.0 Britton-Robinson (B-R) buffer solution (peak at -489 mV), the relationship between the peak current and CA concentration was linear in the range of 1 μM to 90 μM with a detection limit of 0.16 μM. The proposed electrochemical procedure was successfully applied to the determination of carmine food dye in spiked commercially available strawberry flavored milk. The method was extended to the determination of CA in candy and results were in agreement with that obtained by a spectrophotometric comparison method. A cyclic voltammogram of CA in 2.0 B-R buffer electrolyte was obtained on the dropping mercury electrode at pH 2.0 during potential scans from 0.00 mV to 1000 mV versus Ag/AgCl. From repetitive cyclic voltammograms, one cathodic peak at -500 mV and three anodic peaks on the reverse scan between approximately -340 mV and -460 mV were recorded. The influences of some other commonly found inorganic and organic salts on the determination of CA were also examined. The sufficiently good recoveries and low standard deviations for the data reflect the high accuracy and precision of the proposed differential pulse polarographic method.
PubMed: 28911422
DOI: 10.1016/j.jfda.2013.12.002 -
Cellular and Molecular Life Sciences :... Dec 1999Rat heart myocytes undergoing progressive damage demonstrate morphological changes of shortening and swelling followed by the formation of intracellular vacuoles and...
Rat heart myocytes undergoing progressive damage demonstrate morphological changes of shortening and swelling followed by the formation of intracellular vacuoles and plasma membrane blebbing. The damaged myocytes displayed impaired N,N'-tetramethyl-p-phenyldiamine (TMPD) ascorbate-stimulated respiratory activity which was restored by the addition of reduced cytochrome c to the cell culture medium. To clarify the role played by cytochrome c in the impairment of cell respiration, polarographic, spectrophotometric and fluorescence as well as electron microscopy imaging experiments were performed. TMPD/ascorbate-stimulated respiratory activity returned to control levels, at approximately 20 microM cytochrome c, establishing the threshold below which the turnover rate by cytochrome c oxidase in the cell depends on cytochrome concentration. Mildly damaged cardiac myocytes, as indicated by cell shortening, retention of visible striations and free-fluorescein exclusion, together with the absence of lactate dehydrogenase leakage and exclusion of trypan blue, were able to oxidize exogenous cytochrome c and were permeable to fluorescein-conjugated cytochrome c. The results, while consistent with an early cytochrome c release observed at the beginning of cell death, elucidate the role played by cytochrome c in the kinetic control of mitochondrial electron transfer under pathological conditions, particularly those involving the terminal part of the respiratory chain. These data are the first to demonstrate that the sarcolemma of cardiac myocytes, damaged but still viable, is permeable to cytochrome c.
Topics: Animals; Cell Death; Cell Membrane Permeability; Cell Respiration; Cell Size; Cells, Cultured; Cellular Senescence; Cytochrome c Group; Electron Transport; Electron Transport Complex IV; Kinetics; Microscopy, Electron; Microscopy, Fluorescence; Mitochondria, Heart; Myocardium; Oxygen Consumption; Polarography; Rats; Rats, Sprague-Dawley; Sarcolemma; Vacuoles
PubMed: 11212322
DOI: 10.1007/s000180050493 -
Biochimica Et Biophysica Acta Jul 2013To find out whether and how the adenine nucleotide translocator-1 (ANT-1) inhibition due to NH2htau and Aβ1-42 is due to an interplay between these two Alzheimer's...
To find out whether and how the adenine nucleotide translocator-1 (ANT-1) inhibition due to NH2htau and Aβ1-42 is due to an interplay between these two Alzheimer's peptides, ROS and ANT-1 thiols, use was made of mersalyl, a reversible alkylating agent of thiol groups that are oriented toward the external hydrophilic phase, to selectively block and protect, in a reversible manner, the -SH groups of ANT-1. The rate of ATP appearance outside mitochondria was measured as the increase in NADPH absorbance which occurs, following external addition of ADP, when ATP is produced by oxidative phosphorylation and exported from mitochondria in the presence of glucose, hexokinase and glucose-6-phosphate dehydrogenase. We found that the mitochondrial superoxide anions, whose production is induced at the level of Complex I by externally added Aβ1-42 and whose release from mitochondria is significantly reduced by the addition of the VDAC inhibitor DIDS, modify the thiol group/s present at the active site of mitochondrial ANT-1, impair ANT-1 in a mersalyl-prevented manner and abrogate the toxic effect of NH2htau on ANT-1 when Aβ1-42 is already present. A molecular mechanism is proposed in which the pathological Aβ-NH2htau interplay on ANT-1 in Alzheimer's neurons involves the thiol redox state of ANT-1 and the Aβ1-42-induced ROS increase. This result represents an important innovation because it suggests the possibility of using various strategies to protect cells at the mitochondrial level, by stabilizing or restoring mitochondrial function or by interfering with the energy metabolism providing a promising tool for treating or preventing AD.
Topics: Adenine Nucleotide Translocator 1; Adenosine Diphosphate; Adenosine Triphosphate; Alzheimer Disease; Amyloid beta-Peptides; Animals; Cells, Cultured; Cerebellum; Cytoplasmic Granules; Energy Metabolism; Enzyme Inhibitors; Mersalyl; Mitochondria; Models, Neurological; Oxygen Consumption; Peptide Fragments; Polarography; Rats; Rats, Wistar; Reactive Oxygen Species; Superoxides; tau Proteins
PubMed: 23583906
DOI: 10.1016/j.bbabio.2013.04.001 -
Technology in Cancer Research &... Oct 2004The content of water in cancerous and normal human prostate in vitro tissues was shown to be different using near infrared (NIR) spectroscopy. The water absorption peaks...
The content of water in cancerous and normal human prostate in vitro tissues was shown to be different using near infrared (NIR) spectroscopy. The water absorption peaks at 1444 nm and 1944 nm are observed in both types of prostate tissues. The measurements show that less water is contained in cancerous tissues than in normal tissues. The OH stretching vibrational overtone mode at 1444 nm and other water overtone modes provide key spectroscopic fingerprints to detect cancer in prostate tissue. Transmission and backscattered spectral imaging were measured in cancer and normal prostate tissues. The degree of polarization for 700 nm, 800 nm, 1200 nm, and 1450 nm is larger for normal than for cancer tissues. The knowledge about water content offers a potential as a diagnostic tool to better determine and image cancer in prostate and in other tissues types such as breast and cervix using the absorption from vibrational overtones of H(2)O molecules in the NIR.
Topics: Body Water; Humans; Male; Middle Aged; Polarography; Prostate; Prostatic Neoplasms; Reference Values; Spectrophotometry, Infrared
PubMed: 15453814
DOI: 10.1177/153303460400300510 -
Simultaneous voltammetric determination of nitazoxanide and ofloxacin in pharmaceutical formulation.Indian Journal of Pharmaceutical... Sep 2011A simple, sensitive and highly selective electrochemical method was developed for the simultaneous determination of nitazoxanide and ofloxacin in aqueous media...
A simple, sensitive and highly selective electrochemical method was developed for the simultaneous determination of nitazoxanide and ofloxacin in aqueous media (Britton-Robinson buffer, pH-8.36) on a hanging mercury drop electrode (HMDE) using differential pulse polarography (DPP). Using DPP a separation of about 936 mV between the peak oxidation potentials of nitazoxanide and ofloxacin present in binary mixtures was obtained. The quantification limits for the simultaneous determination of nitazoxanide and ofloxacin were 0.083 μg/ml and 0.208 μg/ml, respectively. The proposed method was successfully applied for the simultaneous determination of nitazoxanide and ofloxacin in bulk drug and pharmaceutical tablet formulation.
PubMed: 22923875
DOI: 10.4103/0250-474X.99022 -
Journal of Young Pharmacists : JYP Jun 2013Clarithromycin is an antibacterial widely used for the treatment of a myriad of infections. Various methods including HPLC have been reported for its drug plasma...
Clarithromycin is an antibacterial widely used for the treatment of a myriad of infections. Various methods including HPLC have been reported for its drug plasma concentration but they are more complex. In this study, we developed an electrochemical method for estimation of clarithromycin in blood using differential pulse polarography (DPP) after oral administration of pure clarithromycin suspension. The differential pulse polarography of clarithromycin showed peak with peak potential Ep is -1460 mV SCE at pH 6.5 ± 0.1. The developed electrochemical method was standardized and validated for the determination of clarithromycin in blood serum of albino rats. PK analysis included C max, T max, AUC0-24, elimination rate constant (Kel) and t1/2. C max were found to be 1.34 ± 0.16 mg/ml and 1.99 ± 0.22 mg/ml for plain clarithromycin and suspension formulation, respectively. Effects of ammonium tartarate concentration and pH were also studied as specificity parameters. Developed electrochemical method was found to be simple, accurate method for to estimate blood-clarithromycin profile and can also be used similarly for various dosage forms.
PubMed: 24023459
DOI: 10.1016/j.jyp.2013.06.005 -
The Journal of Biological Chemistry Nov 1975The arrangement of the six cytochrome c oxidase subunits in the inner membrane of bovine heart mitochondria was investigated. The experiments were carried out in three...
The arrangement of the six cytochrome c oxidase subunits in the inner membrane of bovine heart mitochondria was investigated. The experiments were carried out in three steps. In the first step, exposed subunits were coupled to the membrane-impermeant reagent p-diazonium benzene [32S]sulfonate. In the second step, the membranes were lysed with cholate anc cytochrome c oxidase was isolated by immunoprecipitation. In the third step, the six cytochrome c oxidase subunits were separated from each other by dodecyl sulfate-acrylamide gel electrophoresis and scanned for radioactivity. Exposed subunits on the outer side of the mitochondrial inner membrane were identified by labeling intact mitochondria. Exposed subunits on the matrix side of the inner membrane were identified by labeling sonically prepared submitochondrial particles in which the matrix side of the inner membrane is exposed to the suspending medium. Since sonic irradiation leads to a rearrangement of cytochrome c oxidase in a large fraction of the resulting submitochondrial particles, an immunochemical procedure was developed for isolating particles with a low content of displaced cytochrome c oxidase. With mitochondria, subunits II, V, and VI were labeled, whereas in purified submitochondrial particles most of the label was in subunit III. The arrangement of cytochrome c oxidase in the mitochondrial inner membrane is thus transmembraneous and asymmetric; subunits II, V, and VI are situated on the outer side, subunit III is situated on the matrix side, and subunits I and IV are buried in the interior of the membrane. In a study of purified cytochrome c oxidase labeled with p-diazonium benzene [32S]sulfonate, the results were similar to those obtained with the membrane-bound enzyme. Subunits I and IV were inaccessible to the reagent, whereas the other four subunits were accessible. In contrast, all six subunits became labeled if the enzyme was dissociated with dodecyl sulfate before being exposed to the labeling reagent.
Topics: Animals; Binding Sites; Cattle; Cytochrome c Group; Diazonium Compounds; Electron Transport Complex IV; Macromolecular Substances; Membranes; Mitochondria, Muscle; Myocardium; Polarography; Precipitin Tests; Protein Binding
PubMed: 171259
DOI: No ID Found -
Drug News & Perspectives Dec 2007Hypoxia is a pathophysiological aspect that is characteristic for many solid tumors. It is an indicator for tumor aggressiveness and predicts poor treatment outcome.... (Review)
Review
Hypoxia is a pathophysiological aspect that is characteristic for many solid tumors. It is an indicator for tumor aggressiveness and predicts poor treatment outcome. Thus, the assessment of tumor hypoxia would help clinicians to select patients for additional or more specific treatment regimens. Tumor hypoxia can be detected by invasive and noninvasive techniques. The polarographic oxygen electrode method is considered indispensable to establish the effect of antitumor therapy on hypoxia but its invasive nature prevents frequent and repeated use. Therefore, the development of noninvasive techniques is needed and has been directed towards magnetic resonance imaging (MRI) and scintigraphic imaging. Whereas MRI, though promising, is still in its infancy, scintigraphy has demonstrated its ability to depict hypoxic tumor areas. This paper reviews the state-of-the-art in this field. In addition, this paper mentions the related research and new agents to target hypoxia-related makers to interfere with tumor survival and growth.
Topics: Cell Hypoxia; Electrodes; Humans; Magnetic Resonance Imaging; Neoplasms; Neovascularization, Pathologic; Polarography; Prognosis; Radionuclide Imaging
PubMed: 18301796
DOI: 10.1358/dnp.2007.20.10.1181355 -
Anesthesiology May 2002Increasing inspired oxygen concentrations might provide a simple and effective intervention to increase oxygen tension in tissues during controlled hypotension. To test... (Clinical Trial)
Clinical Trial Randomized Controlled Trial
BACKGROUND
Increasing inspired oxygen concentrations might provide a simple and effective intervention to increase oxygen tension in tissues during controlled hypotension. To test this hypothesis, the influence of hyperoxic ventilation (100% O2) on skeletal muscle oxygen partial pressure (Ptio2) in patients receiving sodium nitroprusside-induced controlled hypotension was studied.
METHODS
Forty-two patients undergoing radical prostatectomy were prospectively studied and randomly divided into three groups as follows: (1) Controlled hypotension induced by sodium nitroprusside (mean arterial blood pressure, 50 mmHg) and hyperoxic ventilation (CH-100%; n = 14); (2) controlled hypotension and ventilation with 50% O2 in nitrous oxide (CH-50%; n = 14); and (3) standard normotensive anesthesia with 50% O2 in nitrous oxide (control; n = 14). Ptio2 values were measured continuously in all patients using implantable polarographic microprobes. Arterial blood gases and lactate concentrations were analyzed in 30-min intervals.
RESULTS
Surgical blood loss and transfusion requirements were significantly reduced in both groups receiving hypotensive anesthesia. During surgery, arterial partial pressure of oxy-gen and arterial oxygen content were significantly higher in patients of the CH-100% group. Baseline values of Ptio2 were comparable between the groups (CH-50%: 25.0 +/- 0.7 mmHg; CH-100%: 25.2 +/- 0.2 mmHg; control: 24.5 +/- 0.2 mmHg). After a transient increase in Ptio2 in the CH-100% group during normotension, Ptio2 values returned to baseline and remained unchanged in the control group. Ptio2 decreased significantly during the hypotensive period in the CH-50% group. The lowest mean Ptio2 values were 15.0 +/- 4.1 mmHg in the CH-50% group, 24.2 +/- 4.9 mmHg in the CH-100% group, and 23.5 +/- 3.8 mmHg in the control group. There were no significant changes in lactate plasma concentrations in any group throughout the study period.
CONCLUSIONS
Hyperoxic ventilation improved skeletal muscle tissue oxygenation during sodium nitroprusside-induced hypotension. This improved local tissue oxygenation seems to be most likely due to an increase in convective oxygen transport and the attenuation of hyperoxemia-induced arteriolar vasoconstriction by sodium nitroprusside.
Topics: Aged; Anesthesia; Anesthetics, Inhalation; Antihypertensive Agents; Blood Gas Analysis; Desflurane; Humans; Hypotension, Controlled; Isoflurane; Male; Middle Aged; Muscle, Skeletal; Nitroprusside; Oxygen; Oxygen Consumption; Oxygen Inhalation Therapy; Polarography; Prostatectomy
PubMed: 11981149
DOI: 10.1097/00000542-200205000-00012