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PubMed2005

Potentials for win-win alliances among animal agriculture and forest products industries: application of the principles of industrial ecology and sustainable development.

Commercial forests in many parts of the world are deficient in nitrogen and phosphorus. These nutrient-deficient forests often exist in close proximity to large animal feeding operations, meat processing and other food, textile, or other biomass-processing plants, and municipal waste treatment facilities. Many of these facilities produce large surpluses of nitrogen, phosphorus, and organic matter as gaseous ammonia, urea, uric acid, phosphorus compounds, bacterial sludges, and partially treated municipal wastewaters. These co-existing and substantial nutrient deficiencies and surpluses offer ready-made opportunities for discovery, demonstration, and commercial development of science-based, technology-facilitated, environmentally sound, economically viable, and socially acceptable "win-win alliances" among these major industries based on the principles of industrial ecology and sustainable development. The major challenge is to discover practical means to capture the surplus nutrients and put them to work in forest stands from which value-added products can be produced and sold at a profit.

Agriculture↗

PubMed2001

Coordination of carbonyl and carboxyl oxygen atoms with phosphorus in the presence of hydrogen bonding. P-O donor action.

A series of phosphorus compounds 1-5 containing carbonyl or carboxyl groups was obtained and subjected to X-ray analysis. Syntheses of the phosphoranes 1 and 5 were effected by oxidation reactions using potassium permaganate, while the phosphine oxide 2 was obtained by oxidation with hydrogen peroxide. The readily available phosphines 3 and 4 were included in the study. The structures revealed that P-O coordination occurred for 1-3 in the presence of extensive hydrogen bonding and led to trigonal bipyramidal geometries. A similar structure was observed for 4 in the absence of hydrogen bonding. (31)P chemical shifts indicate retention of the basic coordination geometries in solution. Consideration of the chirality of the phosphoranes 1 and 5 leads to a pair of mirror images that are possible in solution but exist in preferred isomeric forms in the crystalline state. Evaluation of the energies of two competing bonding types indicated a range for P-O coordination above and below the hydrogen bond energy. The results suggest that phosphoryl transfer enzyme mechanisms should benefit by taking into account donor interactions to phosphorus by residues at active sites in addition to the inclusion of hydrogen bonding interactions.

Journal Article↗

PubMed1991

31P magnetic resonance spectroscopy study of cerebral metabolism in developing dog brain and its relationship to neuronal function.

Cerebral metabolism and neuronal function of prefrontal brain cortex were studied in 6 dog litters from birth to 3 months of age. Noninvasive phosphorus magnetic resonance spectroscopy (31P-MRS) was used to observe longitudinal biochemical changes in the phosphorus compounds associated with cerebral metabolism. Neurological tests, examining reflex, motor and sensory nerve function, were performed in conjunction with the 31P-MRS study. During the neonatal period, exponential increases in PCr, Pi, and phophodiesters preceded neurological changes. Phosphomonoesters showed an exponential, nearly linear, decrease and PCr/Pi was maintained during the 3-month period. Developmental increases in high energy phosphates and the maintenance of PCr/Pi indicate that the increased energy demands of the developing animal are met by increased mitochondrial function (ATP turnover).

Aging↗

PubMed1987

Cerebral monitoring in newborn infants by magnetic resonance and near infrared spectroscopy.

Phosphorus magnetic resonance spectroscopy (MRS) and near infrared spectroscopy (NIRS) have been used to study the brains of normal newborn infants and infants with cerebral disorders admitted to a neonatal intensive care unit. MRS, which involves transporting the infant to the spectrometer, allows measurement of mobile phosphorus compounds such as adenosine triphosphate and phosphocreatine in brain tissue, and has been performed on over 160 babies. NIRS gives cotside information about cerebral oxygenation and haemodynamics and has recently been introduced. These techniques, especially when used together, show promise of providing important information about the mechanisms and prognostic significance of hypoxic-ischaemic damage to the brain--the most important cause of permanent neurodevelopmental disabilities in infants who require intensive care.

Brain↗

PubMed1985

Bioenergetic studies of mitochondrial oxidative phosphorylation using 31phosphorus NMR.

The relationship between phosphorylation ratio [( ATP])/[ADP][Pi], phosphocreatine (PCr)/Pi, and ATPase activity was determined for isolated rat heart mitochondria, and the use of phosphorylation ratio and/or PCr/Pi as bioenergetic indices (Chance, B., Eleff, S., Leigh, J. S., Sokolow, D., and Sapega, A. (1981) Proc. Natl. Acad. Sci. U.S.A. 78, 6714-6718) was evaluated. Isolated rat heart mitochondria were suspended at low concentration (0.5-2.0 mg of protein/ ml) in oxygenated KCl/sucrose/4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid medium at 25 degrees C and pyruvate, malate, PCr, ATP, Pi, and Mg2+ were added. Changes in extramitochondrial phosphorus compounds were followed by 31P NMR. The ATPase activity was varied by the addition of potato apyrase. It was found that the logarithm of steady state PCr/Pi decreased linearly with increasing ATPase rate with a PCr/Pi intercept of 32.8 at 0 ATPase rate. The log phosphorylation ratio was also linearly related to the ATPase rate with an extrapolated maximum value of 6.87 at 0 ATPase rate, corresponding to a phosphorylation ratio of 7.41 X 10(6) M(-1) and a delta GATP of -16.3 kcal. The phosphorylation ratio in these experiments (for state 4 respiration) was greater by 1 or 2 orders of magnitude than previously reported for either isolated mitochondria or for whole tissue.

Adenosine Diphosphate↗

PubMed1990

Adenosine triphosphate compartmentation in the rat heart: a 31P spin-lattice relaxation study.

Longitudinal relaxation times (T1) of phosphorus compounds in the perfused rat heart and erythrocytes were measured using the 31P Driven-Equilibrium Single-Pulse Observation of T1 relaxation (DESPOT) method at 33 degrees C. Both creatine phosphate in the heart and the three phosphate groups of adenosine triphosphate (ATP) in erythrocytes showed single-exponential relaxation. The three phosphate groups of ATP in the heart, however, had two T1 components. The T1 values of the short and the long T1 components of the beta-phosphate of ATP were ca. 0.4 and 14 s, respectively. The fraction with the long T1 represented ca. 30% of the total ATP content. These results suggested that there were two major pools of intracellular ATP in the rat heart which could be determined by 31P NMR spectroscopy.

Adenosine Triphosphate↗

PubMed2001

Application of two-dimensional CSI for absolute quantification of phosphorus metabolites in the human liver.

There have recently been a number of studies dealing with the absolute quantification of concentrations of MR-visible phosphorus compounds in different tissues. The use of absolute values rather than intensity ratios may furnish additional information about metabolic changes associated with different diseases. The purpose of this study was to develop a general procedure for measuring molar metabolite concentrations and to apply it with respect to the evaluation of human liver 31P-MRS data measured using a standard slice-selective two-dimensional CSI sequence and commercial 1H/31P surface coil. The experimental determination of all surface coil-related factors influencing signal intensity was undertaken using a gradient echo imaging technique that can be adapted to commercial systems. The resulting values for healthy volunteers (N = 9) showed concentrations of PME = 2.8 +/- 1.3 mM, PDE = 9.9 +/- 2.7 mM, P(i) = 1.7+/-0.7 mM, and ATP = 3.6 +/- 0.9 mM in the human liver. The data are quite consistent with published findings.

Adenosine Triphosphate↗

PubMed1977

31P nuclear magnetic resonance studies of HeLa cells.

A survey of phosphorus compounds present in HeLa cells and their acid extracts has been carried out by (31)P nuclear magnetic resonance spectroscopy at 40 MHz. The proton decoupled (31)P spectrum of the neutralized extract had resolution adequate to enable the identification of the main phosphate compounds. The spectral intensities were converted to concentrations. The lower detection limit with extensive signal averaging was 0.02 mumol for the extract. The composition, listed in order of decreasing concentration, was: inorganic phosphate, ATP, phosphorylcholine, creatine phosphate, UTP, NAD(+), glucose 6-phosphate, beta-D-fructose 1,6-bisphosphate, alpha-D-fructose 1,6-bisphosphate, ADP, alpha-glycerophosphorylcholine, and alpha-glycerophosphorylethanolamine. UTP made up (1/5) of the total nucleotide triphosphate content. The composition was compared to the (31)P spectrum of an extract from a human astrocytoma grown in athymic mice. The signal from P-containing macromolecules such as nucleic acids was not detected in the intact HeLa cell spectrum because of broad lines. Effects of the glycolysis inhibitor iodoacetic acid could be clearly shown in spectra of both the intact cell and the extract as buildup of fructose 1,6-bisphosphate at the expense of ATP, UTP, and creatine phosphate.

HeLa Cells↗

PubMed1991

Positive inotropism in hypothermia partially depends on an increase in maximal Ca(2+)-activated force.

We investigated the contribution of maximal Ca(2+)-activated force to the positive inotropism induced by mild hypothermia. Phosphorus-31 nuclear magnetic resonance spectroscopy revealed that neither energy-related phosphorus compounds in myocardium nor intracellular pH was responsible for the change in contractility. Maximal Ca(2+)-activated pressure (MCAP), the intact-heart correlate of maximal Ca(2+)-activated force, was determined in isolated perfused rabbit hearts by measuring isovolumic left ventricular pressure during tetani at extracellular Ca2+ concentrations greater than or equal to 10 mM. Tetani were elicited by rapid pacing after exposure to ryanodine. MCAP increased by 2.17 +/- 0.28% (mean +/- SE, P less than 0.001, n = 19) for each degree of myocardial cooling between 30 and 38 degrees C. Our results indicate that a primary change in myofilament Ca2+ responsiveness underlies the positive inotropism in hypothermia. The increase in maximal Ca(2+)-activated force may explain the observation of positive inotropism without an upward shift in the relation between oxygen consumption and pressure-volume area, as previously reported for cooled whole hearts.

Animals↗

PubMedDate not supplied

Depth selective quantification of phosphorus metabolites in human calf muscle.

We have used phase modulated rotating frame imaging, a depth selective NMR technique, in conjunction with two methods of calibration, in order to determine the feasibility of quantifying phosphorus compounds in selected regions of a biological sample. In one method, we related peak areas obtained from a sample to the peak area of an external reference located within the receiver coil, previously calibrated against a standard. In the second method we measured peak areas from a standard separately and related them directly to the area of the sample peak. We examined the calf muscles of male volunteers, positioning the coil to obtain signal mainly from the gastrocnemius in the shallow slices and soleus in the deep slices. The concentrations of Pi, phosphocreatine and ATP (in mmol/kg tissue) were 3.0 +/- 0.5, 18 +/- 2 and 4.8 +/- 0.2 at 2 cm depth (mean +/- SD; n = 5). These results are similar to published biopsy data. A comparison with published values obtained from other NMR quantification methods suggests that, while it is possible to obtain consistent results within one laboratory, it is not currently possible to obtain similar results between laboratories. This is evident from the fact that different laboratories report different phosphocreatine/ATP ratios, indicating that the techniques are limited by variations in the processes of data collection and peak area measurement.

Adenosine Triphosphate↗

PubMed1995

Formation and characterization of anodic titanium oxide films containing Ca and P.

Commercially pure titanium was anodized in an electrolytic solution that was dissolved calcium and phosphorus compounds in water, and an AOFCP (anodic titanium oxide film containing Ca and P) was formed. It was found that sodium beta-glycerophosphate (beta-GP) and calcium acetate (CA) were suitable for the electrolytes to form the AOFCP having an equivalent Ca/P ratio to hydroxyapatite (HA). The AOFCP was characterized by scanning electron microscopy (SEM), an energy-dispersive X-ray microanalysis (EDX), and X-ray diffraction (XRD). Numerous micropores and microprojections were observed on the AOFCP by SEM. The composition of the AOFCP, which was measured by EDX, changed according to beta-GP and CA concentration, and the electrolytic voltage. Ca and P in the AOFCP seem to be incorporated into the TiO2 matrix from CA and beta-GP in the electrolyte during the anodic oxidation. Despite the existence of Ca and P in the AOFCP, no calcium phosphate peak was detected by XRD, and the AOFCP consisted of anatase and only a little rutile. The AOFCP, whose contents of Ca and P were low, had a high adhesive strength after soaking in a simulated body fluid for 300 days. When the AOFCP having an equivalent Ca/P ratio to HA was hydrothermally heated at 300 degrees C, HA crystals were precipitated on the AOFCP and completely covered the surface.

Biocompatible Materials↗

PubMed1984

[Determination of two unknown peaks in the 31P magnetic resonance spectrum appearing during the breakdown of high energy phosphates in the ischemic heart and skeletal musculature].

Using the 31-Phosphorus pulsed NMR-technique by FFT information processing it was possible to obtain the following results: The phosphorus compounds were measured as time function in the course of 24 h in isolated skeletal and cardiac muscle of rana temporaria in a dynamic NMR experiment. The shift of the observed resonance lines by increasing intracellular H+ concentration during anoxic conditions will be described in this paper in accordance with the NMR literature. The time course of the beta group of ATP (which is representative for ATP) has been found not to decrease monotonically but rather periodically in a half-hour periodicity until finally a complete fading of ATP in the NMR spectrogram occurs. Besides the resonances described in the literature it was possible to record two additional unknown resonance lines 1.6 and 4.6 ppm apart from the classical alpha- and beta ATP peaks. The peak area of this up to now unknown substance followed a periodic law, regarding the first 2-3 h after preparation. Afterward the concentration dropped to zero. Some shift of the resonance lines of the NMR spectrum could be observed dependent upon the fact that in the muscle cell the ATP normally occurs as a complex with Mg++ ions (MgATP). After separation of Mg++ ions from ATP at low intracellular pH values the resonance lines shifted by some 1-4 ppm. This was tested by test solutions containing MgATP as a complex of free ATP. Although this observation could not sufficiently explain the two as yet unknown lines in the NMR spectra, this result gave rise to further exploration of the phenomenon. To explain the unknown resonance lines, the spectra of the heart and skeletal muscle were compared with that of an adenosine tetraphosphate solution. Based upon the fact that the frequencies of the lines under discussion are identical with those of the adenosine tetraphosphate, one can conclude with a high degree of probability that the as yet unknown lines are originated by adenosine tetraphosphate. If this hypothesis is correct, the concentration of adenosine tetraphosphate could be determined in the order of 1 mM, thus being one third or one quarter of the concentration of the adenosine triphosphate. To give better evidence for the clarification of the newly found substance it will be necessary to record under identical experimental conditions 1H and 13C NMR spectra during the time course of deterioration of the skeletal and cardiac muscle.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenosine Triphosphate↗

PubMed1999

Frontal lobe in vivo (31)P-MRS reveals gender differences in healthy controls, not in schizophrenics.

Phosphorus-31 magnetic resonance spectroscopy ((31)P-MRS) has gained much interest in schizophrenia research in recent years since it allows the non-invasive measurement of high-energy phosphates and phospholipids in vivo. However, until now only differences in metabolite concentrations between certain brain areas of schizophrenic patients and healthy controls have been examined. We investigated the influence of gender on the concentrations of different phosphorus compounds. For this purpose, well-defined volumes in the frontal lobe of 32 healthy controls and 51 schizophrenic in-patients were examined with an image selected in vivo spectroscopy (ISIS) sequence on a whole-body scanner at 1.5 T. Healthy females exhibited increased values of inorganic phosphate (P(i)) and decreased values of phosphocreatine (PCr) in comparison to their male counterparts. In schizophrenic patients such gender differences were not present. Thus, the results can be interpreted in the sense that frontal energy demanding processes are enhanced in female compared to male healthy volunteers; schizophrenia seems to reduce these gender differences.

Adenosine Triphosphate↗

PubMed1998

Occurrence of pesticides in fish tissues, water and soil sediment from Manzala Lake and River Nile.

Pesticides constitute the major source of potential environmental hazard to man and animal as they are present and concentrated in the food chain. This study was conducted on 136 samples of water, sediment and fish for detection and determination of pesticide residues in this ecosystem. Highly significant differences were found in levels of Indian, heptachlor, endrin, dieldrin, P,P'-DDE and propoxur in River Nile water when compared with that of Manzala Lake. Levels of Indian, endrin, malathion and diazinon were significantly higher in soil sediment of Manzala Lake, while the levels of heptachlor, aldrine, P,P'-DDE, DDT, parathion, propoxur and zectran were significantly higher in soil sediment of River Nile. Boury fish of Manzala Lake contained higher levels of heptachlor, aldrin, P,P'-DDE and malathion, while boury fish of River Nile contained a higher level of zectran only. This survey, thus indicated that Manzala Lake and even the River Nile which was used as control are heavily contaminated with chlorinated hydrocarbons (Indian, heptachlor, aldrin, endrin, dieldrin, P,P'-DDE and DDT), organic phosphorus compounds (malathion, dimethoat, diazinon and parathion) and carbamate pesticides (propoxur and zectran).

Agriculture↗

PubMed2006