Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P00750 (PLA)
 16,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Little information is yet available on the economic viability of the production of bio-based bulk chemicals and intermediates from white biotechnology (WB). This paper details a methodology to systematically evaluate the techno-economic prospects of present and future production routes of bio-based bulk chemicals produced with WB. Current and future technology routes are evaluated for 15 products assuming prices of fermentable sugar between 70 euro/t and 400 euro/t and crude oil prices of US $25/barrel and US $50/barrel. The results are compared to current technology routes of petrochemical equivalents. For current state-of-the-art WB processes and a crude oil price of US $25/barrel, WB-based ethanol, 1,3-propanediol, polytrimethylene terephthalate and succinic acid are economically viable. Only three WB products are economically not viable for future technology: acetic acid, ethylene and PLA. Future-technology ethylene and PLA become economically viable for a higher crude oil price (US $50/barrel). Production costs plus profits of WB products decrease by 20-50% when changing from current to future technology for a crude oil price of US $25 per barrel and across all sugar prices. Technological progress in WB can thus contribute significantly to improved economic viability of WB products. A large-scale introduction of WB-based production of economically viable bulk chemicals would therefore be desirable if the environmental impacts are smaller than those of current petrochemical production routes.
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PMID:Today's and tomorrow's bio-based bulk chemicals from white biotechnology: a techno-economic analysis. 1762 39

Ostrich pancreatic phospholipase A(2) (OPLA(2)) was purified from delipidated pancreases. Pure protein was obtained after heat treatment (70 degrees C), precipitation by ammonium sulphate and ethanol, respectively followed by sequential column chromatography on MonoQ Sepharose and size exclusion HPLC column. Purified OPLA(2), which is not a glycosylated protein, was found to be monomeric protein with a molecular mass of 13773.93 Da. A specific activity of 840U/mg for purified OPLA(2) was measured at optimal conditions (pH 8.2 and 37 degrees C) in the presence of 4 mM NaTDC and 10 mM CaCl(2) using PC as substrate. This enzyme was also found to be able to hydrolyze, at low surface pressure, 1,2-dilauroyl-sn-glycero-3 phosphocholine (di C(12)-PC) monolayers. Maximal activity was measured at 5-8 mNm(-1). The sequence of the first 22 amino-acid residues at the N-terminal extremity of purified bird PLA(2) was determined by automatic Edman degradation and showed a high sequence homology with known mammal pancreatic secreted phospholipases A(2).
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PMID:Ostrich pancreatic phospholipase A(2): purification and biochemical characterization. 1765 63

The major objective of this research was to modify the surface properties of poly(lactic acid) (PLA) and poly(hydroxyalkanoate) (PHA) films by using a sequential two-step photografting approach. In step 1, benzophenone was photografted on the film surface and in step 2, hydrophilic monomers acrylamide and acrylic acid were photopolymerized from the film surfaces. Another objective was to study the effect of the reaction solvent in step 2 on surface and bulk properties of these films. ATR-FTIR spectroscopy and water contact angle goniometry were used to characterize the resultant film surfaces. When ethanol was used as the solvent in step 2, there was significant penetration of the monomers into the films, and bulk properties such as toughness and percent elongation at break were drastically affected. The penetration of these monomers into the bulk was characterized using transmission FTIR microspectroscopy. Microtomed sections of the surface-modified films were placed in a diamond compression cell to perform the FTIR microspectroscopic analyses. The observed monomer penetration into the films was successfully reduced by using water instead of ethanol in step 2, and resultant films showed higher toughness and percent elongation at break than films surface-modified using ethanol as a solvent in step 2.
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PMID:Effect of the photoreaction solvent on surface and bulk properties of poly(lactic acid) and poly(hydroxyalkanoate) films. 1809 90

A formyl group-ended poly(DL-lactic acid) (PLA-aldehyde), synthesized in the same manner as reported previously, was utilized to produce the polymeric marker for PLA-related nanoparticles. Namely, pyrene-ended poly(DL-lactic acid) (PLA-pyrene) was prepared as a polymeric marker by the reductive amination of PLA-aldehyde and aminopyrene. Methoxypolyethylene glycol amine-poly(DL-lactic acid) block copolymer (PLA-(MeO-PEG) nanoparticles loaded with PLA-pyrene were prepared, and examined on retention of PLA-pyrene in the nanoparticles, and biodisposition in normal and sarcoma-180 solid tumor-bearing mice. PLA-pyrene was retained stably in PLA-(MeO-PEG) nanoparticles in a PBS-ethanol (7:3, v/v) mixture and a plasma-PBS (1:1, v/v) mixture, indicating that PLA-pyrene might be a useful marker of PLA-(MeO-PEG) nanoparticles themselves. After i.v. injection in normal rats, the plasma level of PLA-pyrene was very high for initial 8h, and accumulated gradually into organs, especially spleen and liver. After i.v. injection in tumor-bearing mice, similar biodistribution profiles of PLA-pyrene were observed, and PLA-pyrene was accumulated well in tumor, suggesting that PLA-(MeO-PEG) nanoparticles should be delivered efficiently to solid tumors. It is suggested that PLA-pyrene might be a useful probe of the nanoparticles themselves. In addition, it was demonstrated that PLA-(MeO-PEG) nanoparticles should be a useful drug carrier for passive tumor targeting.
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PMID:Preparation and biodisposition of methoxypolyethylene glycol amine-poly(DL-lactic acid) copolymer nanoparticles loaded with pyrene-ended poly(DL-lactic acid). 1844 90

The nano-organized LipoParticle assemblies, consisting of polymer particles coated with lipid layers, are investigated with the aim of evidencing the impact of the particle chemical nature on their physicochemical behavior. To this end, these colloidal systems are elaborated from anionic submicrometer poly(styrene) (P(St)) or poly(lactic acid) (PLA) particles, and lipid mixtures composed of zwitterionic 1,2-dipalmitoyl- sn-glycero-3-phosphocholine (DPPC) and cationic 1,2-dipalmitoyl-3-trimethylammonium-propane (DPTAP). As revealed by various experimental techniques, such as quasielastic light scattering, zeta potential measurements, transmission electron microscopy, and 1H NMR spectroscopy, the features of both LipoParticle systems are similar when cationic lipid formulations (DPPC/DPTAP mixtures) are used. This result emphasizes the major role of electrostatic interactions as driving forces in the assembly elaboration process. Conversely, the assemblies prepared only with the zwitterionic DPPC lipid are strongly dependent on the particle chemical nature. The structural characteristics of the assemblies based on PLA particles are not controlled and correspond to aggregates, contrary to P(St) particles. To understand this specific phenomenon, and to consequently improve the final organization of these assemblies which are potentially of great interest in biotechnology and biomedicine, numerous investigations are carried out such as the studies of the impact of the ionic strength and the pH of the preparation media, as well as the presence of ethanol (involved in the PLA particle synthesis) or the mean size of the lipid vesicles. From the resulting data and according to the nature of spherical solid support, hydrophobic effects, hydrogen bonds, or dipole-dipole interactions would also appear to influence the LipoParticle elaboration in the case of zwitterionic lipid formulation.
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PMID:Effect of the polymer nature on the structural organization of lipid/polymer particle assemblies. 1884 2

Chicken pancreatic phospholipase A(2) (ChPLA(2)) was purified from delipidated pancreases using ammonium sulfate and ethanol precipitation, followed by sequential column chromatography steps on MonoQ Sepharose and size exclusion HPLC columns. ChPLA(2) was found to be a nonglycosylated monomeric protein with a molecular mass of 14 kDa and a specific activity of 400 U x mg(-1) in the presence of 1 mM sodium taurodeoxycholate and 4 mM CaCl(2) with phosphatidylcholine as substrate. The N-terminal sequence of the first 15 amino acids of ChPLA(2) was determined, and showed a high degree of homology with known mammal pancreatic phospholipases A(2). The gene encoding the mature ChPLA(2) was cloned and sequenced. The deduced amino acid sequence of the mature ChPLA(2) confirmed the high level of identity with mammal pancreatic PLA(2). To investigate the structure-activity relationships, a 3D model of group IB ChPLA(2) was built using the porcine pancreatic phospholipase A(2) structure as template.
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PMID:Biochemical and molecular characterization of purified chicken pancreatic phospholipase A2. 1964 24

An inverse association between moderate alcohol intake and cardiovascular risk, in particular coronary disease and ischemic stroke, has been demonstrated in many epidemiologic studies. In addition, several not primarily vascular diseases are also known to occur less frequently in moderate drinkers than in nondrinkers, whereas excess drinking is unquestionably harmful. As a consequence, strong concern exists on the possibility that at any dosage the benefit of alcohol could overcome its harmful effects. Alcohol affects several biochemical factors that have potential cardioprotective benefits, including lipids, platelet aggregation, fibrinogen, tissue-plasminogen activator, plasminogen-activator inhibitor and omega-3 fatty acids. Wine possibly acts through mechanisms that might provide additional cardiovascular benefits. Mechanisms supporting the protective effect of moderate alcohol intake against cardiovascular disease, and epidemiologic evidence concerning the relationship between alcohol dosing and vascular and all-cause mortality are discussed in this review.
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PMID:Alcohol consumption and cardiovascular risk: mechanisms of action and epidemiologic perspectives. 1971 11

The interactions of post-culture treatments reagents used for fixing, lysing and cell quantification on poly(lactide-co-glycolide) (PLGA) flat sheet membrane scaffolds are presented. Lysing with Alkaline buffer solution/Triton X-100/MilliQ water (ATM) and fixing with 10% Neutral Buffered Formalin (10% NBF) had no affect on membrane structure while fixing with 95% ethanol caused smoothing of the surface, shrinkage and a reduction in surface area of 55, 48 and 33, for 100:0, 75:25 and 50:50 (PLA:PGA), respectively. PicoGreen assay was selected for cell (560pZIPv.neo) quantification since the background noise would not affect readings for cell numbers over 3,000 cells/cm(2), while the background reading was too high for MTT and Methylene Blue (MB). MB at 0.5% (w/v) was, however, deemed suitable for visualising cell morphology on the membranes. Furthermore ATM buffer was suitable for the PicoGreen assay, which allows the same samples to be used for quantification of alkaline phosphatase activity.
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PMID:Post-culture treatment protocols for PLGA membrane scaffolds. 1982 Oct 75

Enzymatic synthesis of phospholipids (PLs) containing polyunsaturated fatty acids (PUFAs) was studied. The main purpose was to establish an efficient production method for PLs containing docosahexaenoic acid or eicosapentaenoic acid using only food-compatible reagents. Phospholipase A(2) (PLA(2))-mediated ester synthesis was employed to introduce the PUFAs into the sn-2 position of lysophospholipid (LPL) to yield PUFA-containing PLs. When LPL and the fatty acids were reacted in glycerol in the presence of porcine pancreas PLA(2), the reaction was not very effective. However, it was found that addition of certain kinds of amino acids such as glycine or L-alanine in the reaction mixture improved the reaction. After the reaction, the synthesized PLs were extracted selectively with ethanol and n-hexane, leaving the unreacted LPL, amino acids and the enzyme remained in the glycerol layer. It was confirmed that the enzyme remained in the glycerol layer could be reused by adding fresh substrates for the subsequent reactions.
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PMID:Synthesis of phospholipids containing polyunsaturated fatty acids by phospholipase A(2)-mediated esterification with food-compatible reagents. 2051 71

To examine population mean variations in plasma fibrinogen and fibrinolytic variables, and their rela tions with cardiovascular risk characteristics among Japanese middle-aged men, a cross-sectional study was conducted for a total of 245 men aged 50-59 years in three population-based samples: residents in rural communities of northeast and central Japan and urban white-collar workers. Age-adjusted mean value of plasma fibrinogen, tissue plasminogen activator antigen (t-PA antigen), plasminogen activator inhibitor 1 antigen (PAI-1 antigen) did not differ significantly among the populations. Mean value of tissue plasminogen activator activity (t-PA activity) was lower in central rural residents than in northeast rural men. According to multiple linear regression analyses, there were positive associations of t-PA and PAI-1 antigens with serum triglyceride levels, serum insulin and waist-hip ratio within each population and the total samples. A positive association between these fibrinolytic variables and usual ethanol intake was also observed. Smoking was significantly associated with plasma fibrinogen and PAI-1 antigen but not with t-PA antigen or activity. Activity of t-PA was inversely associated with body mass index, and a mean difference in t-PA activity was in part explained by a mean difference in body mass index. In conclusion, population mean values of plasma fibrinogen and fibrinolytic variables did not differ among three Japanese populations except for mean t-PA activity. Reduced fibrinolysis expressed as increased PAI-1 antigen was associated with smoking and the status of insulin resistance, such as high levels of serum insulin, serum triglycerides and waist-hip ratio.
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PMID:Plasma fibrinogen, tissue plasminogen activator, plasminogen activator inhibitor 1, and their related factors in three Japanese population samples. 2143 96


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