The Initial-Value Problem of Spherically Symmetric Wyman Sector Nonsymmetric Gravitational Theory

We cast the four-dimensional field equations of the Nonsymmetric Gravitational Theory (NGT) into a form appropriate for numerical study. In doing so, we have restricted ourselves to spherically symmetric spacetimes, and we have kept only the Wyman sector of the theory. We investigate the well-posedness of the initial-value problem of NGT for a particular data set consisting of a pulse in the antisymmetric field on an asymptotically flat space background. We include some analytic results on the solvability of the initial-value problem which allow us to place limits on the regions of the parameter space where the initial-value problem is solvable. These results are confirmed by numerically solving the constraints.Comment: REVTeX 3.0 with epsf macros and AMS symbols, 18 pages, 9 figure

Abelian Anomalies in Nonlocal Regularization

Nonlocal regularization of QED is shown to possess an axial anomaly of the same form as other regularization schemes. The Noether current is explicitly constructed and the symmetries are shown to be violated, whereas the identities constructed when one properly considers the contribution from the path integral measure are respected. We also discuss the barrier to quantizing the fully gauged chiral invariant theory, and consequences.Comment: 21 pages, UTPT-93-0

Structure and cardioprotective activities of polar lipids of olive pomace, olive pomace-enriched fish feed and olive pomace fed gilthead sea bream (Sparus aurata)

peer-reviewedTotal lipids of olive pomace (OP), olive pomace diet (OP diet), fish oil diet (FO diet) and fish fillets of farmed gilthead sea bream (fish fed with FO diet and OP diet respectively) were extracted and separated into polar (TPL) and neutral (TNL) lipids. All samples were assessed for their in vitro activity against washed rabbit platelets aggregation induced by Platelet Activating Factor (PAF) and they were further analyzed by electrospray-mass spectrometry. The high levels of palmitic (16:0), oleic (18:1 cis ω-9), linoleic (18:2 ω-6) and docosapentanoic acid (DPA 22:5 ω-3) contained in both OP and FO diets are reflected to the gilthead sea breams fed with the individual diet respectively, while the gilthead sea bream fed with FO diet displays a decrease in DPA. All samples contained various glycerophospholipids species. Two PE species were identified in OP, OP diet and fish fed with OP diet and not in FO diet, while that might be an indication that these substances are likely to be the key polar phospholipids that have the ability to be in vitro PAF inhibitors, i.e. inhibit the formation of atherosclerotic plaques in blood arteries.ACCEPTEDpeer-reviewe

Macrobenthic infaunal communities associated with deep‐sea hydrocarbon seeps in the northern Gulf of Mexico

There are thousands of seeps in the deep ocean worldwide; however, many questions remain about their contributions to global biodiversity and the surrounding deep‐sea environment. In addition to being globally distributed, seeps provide several benefits to humans such as unique habitats, organisms with novel genes, and carbon regulation. The purpose of this study is to determine whether there are unique seep macrobenthic assemblages, by comparing seep and nonseep environments, different seep habitats, and seeps at different depths and locations. Infaunal community composition, diversity, and abundance were examined between seep and nonseep background environments and among three seep habitats (i.e., microbial mats, tubeworms, and soft‐bottom seeps). Abundances were higher at seep sites compared to background areas. Abundance and diversity also differed among microbial mat, tubeworm, and soft‐bottom seep habitats. Although seeps contained different macrobenthic assemblages than nonseep areas, infaunal communities were also generally unique for each seep. Variability was 75% greater within communities near seeps compared to communities in background areas. Thus, high variability in community structure characterized seep communities rather than specific taxa. The lack of similarity among seep sites supports the idea that there are no specific infauna that can be used as indicators of seepage throughout the northern Gulf of Mexico, at least at higher taxonomic levels

Re(I) tricarbonyl complex of 1,10-phenanthroline-5,6-dione: DNA binding, cytotoxicity, antiinflammatory and anti-coagulant effects towards platelet activating factor

The complex fac-[Re(CO)3(phendione)Cl] (1) (where phendione = 1,10-phenanthroline-5,6-dione) has been synthesized and fully characterized by UV–visible, FTIR, and NMR techniques. The DNA binding properties of 1 are investigated by UV-spectrophotometric (melting curves), covalent binding assay, CV (cyclic voltammetry), circular dichroism (CD) and viscosity measurements. Experimental data indicate that 1 fits into the major groove without disrupting the helical structure of the B-DNA in contrast to the free phendione which intercalates within the base pairs of DNA. Upon irradiation, complex 1promotes the cleavage of plasmid pBR322 DNA from supercoiled form I to nicked form II via a proton coupled electron transfer mechanism. This comes as a result of experimental data in anaerobic/aerobic conditions and in the presence of DMSO. The biological activities of 1 and its precursors [Re(CO)5Cl] and phendione are tested towards a series of cancerous cell lines as glioblastoma (T98G), prostate cancer (PC3) and breast cancer (MCF-7) as well as platelet activating factor (PAF)-aggregation. Moreover, all the aforementioned compounds are tested for their ability to modulate PAF-basic metabolic enzyme activities in preparations of rabbit leukolytes. The in vitro experiments indicate that phendione has a better antitumor effect than cisplatin whereas [Re(CO)5Cl] is a better PAF inhibitor than both the phendione ligand and 1. Moreover, for the first time it is indicated that [Re(CO)5Cl], with a IC50 of 17 nM is comparable to the widely used PAF receptor antagonists, BN52021 and WEB2170 with IC50 of 30 and 20 nM, respectively, whereas 1 affects PAF-catabolism

Fish polar lipids retard atherosclerosis in rabbits by down-regulating PAF biosynthesis and up-regulating PAF catabolism

<p>Abstract</p> <p>Background</p> <p>Platelet activating factor (PAF) has been proposed as a key factor and initial trigger in atherosclerosis. Recently, a modulation of PAF metabolism by bioactive food constituents has been suggested. In this study we investigated the effect of fish polar lipid consumption on PAF metabolism.</p> <p>Results</p> <p>The specific activities of four PAF metabolic enzymes; in leukocytes, platelets and plasma, and PAF concentration; either in blood cells or plasma were determined. Samples were acquired at the beginning and at the end of a previously conducted study in male New Zealand white rabbits that were fed for 45 days with atherogenic diet supplemented (group-B, n = 6) or not (group-A, n = 6) with gilthead sea bream (<it>Sparus aurata</it>) polar lipids.</p> <p>The specific activity of PAF-Acetylhydrolase (PAF-AH); a catabolic enzyme of PAF, was decreased in rabbits' platelets of both A and B groups and in rabbits' leukocytes of group A (p < 0.05). On the other hand the specific activity of Lipoprotein-associated Phospholipase A2 (Lp-PLA2); the catabolic enzyme of PAF in plasma was increased in both A and B groups in both leukocytes and platelets (p < 0.05). PAF-cholinephosphotransferase (PAF-CPT); a biosynthetic enzyme of PAF showed increased specific activity only in rabbits' leukocytes of group A (p < 0.05). Neither of the two groups showed any change in Lyso-PAF-acetyltransferase (Lyso-PAF-AT) specific activity (p > 0.05). Free and bound PAF levels increased in group A while decreased in group B (p < 0.05).</p> <p>Conclusions</p> <p>Gilthead sea bream (<it>Sparus aurata</it>) polar lipids modulate PAF metabolism upon atherosclerotic conditions in rabbits leading to lower PAF levels and activity in blood of rabbits with reduced early atherosclerotic lesions compared to control group.</p

Hydroxyl-platelet-activating factor exists in blood of healthy volunteers and periodontal patients.

Periodontal diseases are localized chronic inflammatory conditions of the gingival and underlying bone and connective tissue. Platelet-activating factor (PAF), a potent inflammatory phospholipid mediator that has been previously detected in elevated levels in inflamed gingival tissues, in gingival crevicular fluid and in saliva, is implicated in periodontal disease. Our results from previous studies showed that the biologically active phospholipid detected in gingival crevicular fluid is a hydroxyl-PAF analogue. In this study, hydroxyl-PAF analogue was detected for the first time in human blood derived from patients with chronic periodontitis as well as from periodontally healthy volunteers. The hydroxyl-PAF analogue was purified by high-performance liquid chromatography, detected by biological assays and identified by electrospray analysis. In addition, the quantitative determination of PAF and hydroxyl-PAF analogue (expressed as PAF-like activity) showed a statistically significant increase in the ratio of hydroxyl-PAF analogue levels to PAF levels in periodontal patients, suggesting that this bioactive lipid may play a role in oral inflammation

Structurally Diverse Metal Coordination Compounds, Bearing Imidodiphosphinate and Diphosphinoamine Ligands, as Potential Inhibitors of the Platelet Activating Factor

Metal complexes bearing dichalcogenated imidodiphosphinate [R2P(E)NP(E)R2′]− ligands (E = O, S, Se, Te), which act as (E,E) chelates, exhibit a remarkable variety of three-dimensional structures. A series of such complexes, namely, square-planar [Cu{(OPPh2)(OPPh2)N-O, O}2], tetrahedral [Zn{(EPPh2)(EPPh2)N-E,E}2], E = O, S, and octahedral [Ga{(OPPh2)(OPPh2)N-O,O}3], were tested as potential inhibitors of either the platelet activating factor (PAF)- or thrombin-induced aggregation in both washed rabbit platelets and rabbit platelet rich plasma. For comparison, square-planar [Ni{(Ph2P)2N-S-CHMePh-P, P}X2], X = Cl, Br, the corresponding metal salts of all complexes and the (OPPh2)(OPPh2)NH ligand were also investigated. Ga(O,O)3 showed the highest anti-PAF activity but did not inhibit the thrombin-related pathway, whereas Zn(S,S)2, with also a significant PAF inhibitory effect, exhibited the highest thrombin-related inhibition. Zn(O,O)2 and Cu(O,O)2 inhibited moderately both PAF and thrombin, being more effective towards PAF. This work shows that the PAF-inhibitory action depends on the structure of the complexes studied, with the bulkier Ga(O,O)3 being the most efficient and selective inhibitor

Behavioral and antioxidant activity of a tosylbenz[g]indolamine derivative. A proposed better profile for a potential antipsychotic agent

BACKGROUND: Tardive dyskinesia (TD) is a major limitation of older antipsychotics. Newer antipsychotics have various other side effects such as weight gain, hyperglycemia, etc. In a previous study we have shown that an indolamine molecule expresses a moderate binding affinity at the dopamine D(2 )and serotonin 5-HT(1A )receptors in in vitro competition binding assays. In the present work, we tested its p-toluenesulfonyl derivative (TPBIA) for behavioral effects in rats, related to interactions with central dopamine receptors and its antioxidant activity. METHODS: Adult male Fischer-344 rats grouped as: i) Untreated rats: TPBIA was administered i.p. in various doses ii) Apomorphine-treated rats: were treated with apomorphine (1 mg kg(-1), i.p.) 10 min after the administration of TPBIA. Afterwards the rats were placed individually in the activity cage and their motor behaviour was recorded for the next 30 min The antioxidant potential of TPBIA was investigated in the model of in vitro non enzymatic lipid peroxidation. RESULTS: i) In non-pretreated rats, TPBIA reduces the activity by 39 and 82% respectively, ii) In apomorphine pretreated rats, TPBIA reverses the hyperactivity and stereotype behaviour induced by apomorphine. Also TPBIA completely inhibits the peroxidation of rat liver microsome preparations at concentrations of 0.5, 0.25 and 0.1 mM. CONCLUSION: TPBIA exerts dopamine antagonistic activity in the central nervous system. In addition, its antioxidant effect is a desirable property, since TD has been partially attributed, to oxidative stress. Further research is needed to test whether TPBIA may be used as an antipsychotic agent