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PubMedDate not supplied

Comparison of red cell cholinesterase and plasma cholinesterase activities in early detection of organo-phosphorus toxicity in exposed industrial workers in Port Harcourt, Nigeria.

BACKGROUND: The Niger Delta region of Nigeria has a high concentration of companies using organo-phosphorus compounds with workers who have been exposed to these compounds for varying lengths of time resulting in toxic manifestations in some of the workers. Studies have revealed that plasma cholinesterase and red cell cholinesterase levels are reduced following organo-phosphorus toxicity. This study looks at cholinesterase levels in plasma and red cell in the occupationally exposed groups and control with a view to determining which will be more useful in the early detection of organo-phosphorus toxicity. METHOD: Fourty seven subjects with early symptoms of organo-phosphorus toxicity who have worked for more than 4 years with organo-phosphorus compounds were selected from five companies localized around the same area in Port Harcourt. Fifty subjects who do not work directly with organo-phosporus compounds from the same companies as the 47 workers above but not working directly in the organo-phosphorus units were also studied while 50 persons working in the civil service were recruited as controls. The kinetic colorimetric method was used for measuring plasma and red cell cholinesterase activity Result: The results showed significant reduction in the mean plasma cholinesterase activity in the chronically exposed subjects (4614. +/- 532) who showed symptoms of toxicity when compared with that of the control group (8095 +/- 575). There was no statistical difference in the mean red cell cholinesterase activity of the chronically exposed group (7998. +/- 948) when compared with that of the control (8115. +/- 712) P > 0.05 CONCLUSION: The effect of organo-phosphorus poisoning occurs early and is more marked in plasma cholinesterase than in the red cell cholinesterase. Plasma cholinesterase is thus more useful in early detection of organo-phosphorus toxicity than red cell cholinesterase.

Adult↗
PubMed1966

Compositional changes of douglas fir seeds during germination.

Changes in weight, water content, nucleic acids, nucleotides, carbohydrates, lipids, nitrogenous and phosphorus compounds in embryo and gametophyte of Douglas fir seeds (Pseudotsuga menziesii Franco) were studied at 6 stages of germination. Lipids, proteins, and reserve phosphorus compounds in the gametophyte were utilized for the synthesis of carbohydrates, structural components, and soluble compounds in the seedling.The general quantitative metabolic changes that occur during germination of Douglas fir seeds are comparable to those known for angiosperm seeds.

Journal Article↗
PubMed1987

Influence of heart rate on metabolic and hemodynamic parameters in the Syrian hamster cardiomyopathy.

The effect of varying heart rate in 155- to 170-day-old isolated, perfused cardiomyopathic Syrian hamster hearts was evaluated by 31P nuclear magnetic resonance spectroscopy. At a low paced heart rate of 170 bpm, cardiomyopathic hearts did not differ from normal hearts except for a lower developed left ventricular pressure. As pacing rate was increased progressively to 270/min, cardiomyopathic hearts showed prolongation of contraction, which led to a pronounced rise in diastolic pressure as the interstimulus interval shortened. This was accompanied by a marked decrease in energy-rich phosphorus compounds. By contrast, increasing heart rate in normal hearts did not change left ventricular pressure and caused only a mild reduction in energy-rich phosphorus compounds. Intracellular pH of cardiomyopathic animals paced at 270 bpm was significantly lower than in normal animals. Thus, indices reflecting mitochondrial function of 155- to 170-day-old cardiomyopathic hamsters appear adequate at low heart rate. Increasing the heart rate unmasks latent mitochondrial dysfunction.

Adenosine Triphosphate↗
PubMed1999

[Chronic kidney failure and hearing disorders].

Long-term occupational exposure to phosphorus compounds cause cochleovestibular disorders which, at the stage of marked intoxication, manifest with symptoms of cochlear neuritis with signs of vestibular dysfunction. This affection, among other manifestations of chronic occupational phosphorus intoxication, should be taken in consideration by the experts assessing working ability of employees in contact with phosphorus compounds.

Adult↗
PubMed1993

31P NMR examination of phosphorus metabolites in the aqueous, acidic, and organic extracts of Phaseolus vulgaris seeds.

31P NMR spectroscopy was used to compare the phosphorus compound content in aqueous, acidic, and organic extracts of Phaseolus vulgaris seeds. Two chloroform-methanol and three ethanol extractions were used to isolate phospholipids from dry cotyledons and the phospholipid profiles were compared. Variations in phospholipid composition and artificially high concentrations of lysophosphatidylcholine were observed in the ethanol extracts. Other phosphorus compounds were extracted using perchloric acid, trichloroacetic acid, trichloroacetic acid in ether, hydrochloric acid, boiling water, and aqueous Hepes. The Hepes extraction was introduced in order to compare the results of a gentle procedure with those involving heat and acid treatments. Low concentrations of phospho-sugars and other phosphorus metabolites were found in all these extracts. High concentrations of phytate were found in all aqueous and acidic extractions; however, 31P NMR spectra of aqueous extractions did not show the phytate resonance. The NMR silence of the phytate resonances is attributed to complexation of phytate. The 31P NMR spectra of aqueous extracts contained a broad resonance at 0.1 ppm assigned to protein-bound RNA. Various extraction procedures on the same biological material are presented, and the comparison of these methods will facilitate future analysis and interpretation of literature reports involving these methods of tissue analysis.

Chemistry Techniques, Analytical↗
PubMed1978

Phosphorus-nitrogen compounds. 22. Synthesis and antitumor activity of arylsulfonylhydrazone analogues.

A series of pyridine-2-carboxaldehyde N-oxide and pyridine-2-carboxaldehyde (thio)phosphoric hydrazones and two cupric chelates was synthesized. The hydrazones, chelates, and combinations of hydrazones and cupric chloride were tested against mice bearing P388 lymphocytic leukemia, Sarcoma 180, or Ehrlich carcinoma ascites cells. The effects of various structural modifications of the hydrazones on antineoplastic activity for this latter system were determined. In general, the pyridine-2-carboxaldehyde thiophosphoric monohydrazones containing P-phenyl or P-phenoxy substituents possessed the highest activity when concurrently administered with cupric ion, whereas the ligands themselves were inactive. Two of the compounds were prepared with P-hydroxyl groups to permit increased hydrophilicity. The ability of the hydrazones to chelate cupric, ferrous, and cobaltous salts was investigated, and discrepancies between determined and calculated log P values for three compounds are discussed.

Animals↗
PubMed2003

Extraction of inorganic acids with neutral phosphorus extractants based on a reverse micelle/microemulsion mechanism.

The extraction of inorganic acids such as HCl, HNO(3), H(2)SO(4), and HClO(4) has been investigated in three neutral phosphorus compound systems, i.e., tri-n-butyl phosphate (TBP), di-isoamylmethyl phosphonate (DiAMP), and trialkylphosphine oxide (TRPO, C(6)-C(8)), using n-heptane as a diluent. The techniques of electrical conductivity, Fourier transform infrared (FTIR) spectroscopy, 1H NMR, and dynamic laser scattering (DLS) were selected to characterize the organic phases. The results indicate that the interaction between acids and neutral phosphorus compounds follows a molecule-ion combination mechanism. When the acid in the organic phase reaches a certain concentration, the molecular-ion species have a tendency to self-assemble and form reverse micelles/microemulsions (W/O). The further increase of the acid concentration leads the organic phase to split into two layers. Extractants and acids are mainly located in the down layer, in which aggregations are formed. The tendency to form microemulsions follows TRPO > DiAMP > TBP.

Journal Article↗
PubMed2006

Phosphorus-nitrogen compounds. Part 13. Syntheses, crystal structures, spectroscopic, stereogenic, and anisochronic properties of novel spiro-ansa-spiro-, spiro-bino-spiro-, and spiro-crypta phosphazene derivatives.

The condensation reactions of N2Ox (x = 2, 3) donor-type aminopodand (4) and dibenzo-diaza-crown ethers (5, 6, and 9) with hexachlorocyclotriphosphazatriene, N3P3Cl6, produce two kinds of partially substituted novel phosphazene derivatives, namely, spiro-bino-spiro- (19) and spiro-crypta (21, 22, and 25) phosphazenes. The partially substituted spiro-ansa-spiro-phosphazene (11) reacted with pyrrolidine and 1,4-dioxa-8-azaspiro[4,5]decane (DASD) give the corresponding new fully substituted phosphazenes (14 and 16). Unexpectedly, the reactions of 23 and 24 with pyrrolidine result in only geminal crypta phosphazenes (26 and 27). The solid-state structures of 16 and 22 have been determined by X-ray diffraction techniques. The relative inner hole-size of the macrocycle in the radii of 22 is 1.27 A. The relationship between the exocyclic NPN (alpha') and endocyclic (alpha) bond angles for spiro-crypta phosphazenes and exocyclic OPN (alpha') bond angles for spiro-ansa-spiro- and spiro-bino-spiro-phosphazenes with 31P NMR chemical shifts of NPN and OPN phosphorus atoms, respectively, have been investigated. The structures of 10, 14, 16, 19, 21, 22, and 25-27 have also been examined by FTIR, 1H, 13C, and 31P NMR, HETCOR, MS, and elemental analyses. The 31P NMR spectra of 10, 21, 22, and 25 indicate that the compounds have anisochrony. In compounds 16 and 22, the spirocyclic nitrogen atoms have pyramidal geometries resulting in stereogenic properties.

Journal Article↗
PubMed2005

Microbially mediated phosphine emission.

There is still a lot of controversy in literature concerning the question whether a biochemical system exists enabling micro-organisms to reduce phosphate to phosphine gas. The search for so-called 'de novo synthesised' phosphine is complicated by the fact that soils, slurries, sludges, etc., which are often used as inocula, usually contain matrix bound phosphine (MBP). Matrix bound phosphine is a general term used to indicate non-gaseous reduced phosphorus compounds that are transformed into phosphine gas upon reaction with bases or acids. A study was carried out to compare the different digestion methods, used to transform matrix bound phosphine into phosphine gas. It was demonstrated that caustic and acidic digestion methods should be used to measure the matrix bound phosphine of the inoculum prior to inoculation to avoid false positive results concerning de novo synthesis. This is especially true if anthropogenically influenced inocula possibly containing minute steel or aluminium particles are used. The comparative study on different digestion methods also revealed that the fraction of phosphorus in mild steel, converted to phosphine during acid corrosion depended on the temperature. Following these preliminary studies, anaerobic growth experiments were set up using different inocula and media to study the emission of phosphine gas. Phosphine was detected in the headspace gases and its quantity and timeframe of emission depended on the medium composition, suggesting microbially mediated formation of the gas. The amount of phosphine emitted during the growth experiments never exceeded the bound phosphine present in inocula, prior to inoculation. Hence, de novo synthesis of phosphine from phosphate could not be demonstrated. Yet, microbially mediated conversion to phosphine of hitherto unknown reduced phosphorus compounds in the inoculum was evidenced.

Bacteria, Anaerobic↗