928 resultados para 2 CARBOXY-GROUPS


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Phospholipases A(2) (PLA(2)) are key enzymes in membrane metabolism. The release of fatty acids and lysophospholipids by PLA(2) activates several intra-cellular second messenger cascades that regulate a wide variety of physiological responses. The aim of the present study is to describe a radioenzymatic assay to determine the activity of three main PLA(2) subtypes in platelets, namely extracellular calcium-dependent PLA(2) (sPLA(2)) and intracellular calcium-dependent (cPLA(2)) and calcium-independent PLA(2) (iPLA(2)). The differentiation of these distinct PLA(2) subtypes was based on the enzyme substrate preference (arachdonic acid or palmitoyl acid) and calcium concentration. Our results indicate that this new assay is feasible, precise and specific to measure the activity of the aforementioned subtypes of PLA(2). Therefore, this protocol can be used to investigate modifications of PLA(2) homeostasis in distinct biological models addressing the pathophysiology of many medical and neuropsychiatric disorders such as schizophrenia and Alzheimer's disease. (C) 2012 Elsevier Ltd. All rights reserved.

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Electrostatic and hydrophobic interactions govern most of the properties of supramolecular systems, which is the reason determining the degree of ionization of macromolecules has become crucial for many applications. In this paper, we show that highresolution ultraviolet spectroscopy (VUV) can be used to determine the degree of ionization and its effect on the electronic excitation energies of layer-by-layer (LbL) films of poly(allylamine hydrochloride) (PAH) and poly[1-[4-(3-carboxy-4 hydroxyphenylazo)- benzene sulfonamido]-1,2-ethanediyl, sodium salt] (PAZO). A full assignment of the VUV peaks of these polyelectrolytes in solution and in cast or LbL films could be made, with their pH dependence allowing us to determine the p'K IND. a' using the Henderson-Hasselbach equation. The p'K IND. a' for PAZO increased from ca. 6 in solution to ca. 7.3 in LbL films owing to the charge transfer from PAH. Significantly, even using solutions at a fixed pH for PAH, the amount adsorbed on the LbL films still varied with the pH of the PAZO solutions due to these molecular-level interactions. Therefore, the procedure based on a comparison of VUV spectra from solutions and films obtained under distinct conditions is useful to determine the degree of dissociation of macromolecules, in addition to permitting interrogation of interface effects in multilayer films.

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Objective. To investigate the association of the three major genetic groups of Mycobacterium tuberculosis with pulmonary and extra-pulmonary tuberculosis in clustered and non-clustered TB cases in the Houston area. ^ Study design. Secondary analysis of an ambi-directional study. ^ Study population. Three hundred fifty-eight confirmed cases of tuberculosis in the Houston that occurred between October 1995 and May 1997, who had been interviewed by the Houston T13 Initiative staff at Baylor College of Medicine, and whose isolates have had their DNA fingerprint and genetic group determined. ^ Exclusions. Individuals whose mycobacterial genotype was unknown, or whose data variables were unavailable. ^ Source of data. Laboratory results, patient interviews, and medical records at clinics and hospitals of the study population. ^ Results. In clustered cases, the majority of both, pulmonary and extra-pulmonary TB cases were caused by genetic group 1. Independent factors were assessed to determine the interactions that may influence the site of infection or increase the risk for one site or another. HIV negative males were protected against extra-pulmonary TB compared to HIV negative females. Individuals ages 1–14 years were at higher risk of having extra-pulmonary TB. Group 3 organisms were found less frequently in the total population in general, especially in extra-pulmonary disease. This supports the evidence in previous studies that this group is the least virulent and genetically distinct from the other two groups. Group 1 was found more frequently among African Americans than other ethnic groups, a trend for future investigations. ^ Among the non-clustered cases, group 2 organisms were the majority of the organisms found in both sites. They were also the majority of organisms found in African Americans, Caucasians, and Hispanics causing the majority of the infections at both sites. However, group 1 organisms were the overwhelming majority found in Asian/Pacific Islander individuals, which may indicate these organisms are either endemic to that area, or that there is an ethnic biological factor involved. This may also be due to a systematic bias, since isolates from individuals from that geographic region lack adequate copies of the insertion sequence IS6110, which leads to their placement in the non-clustered population. ^ The three genetic groups of Mycobacterium tuberculosis were not found equally distributed between sites of infection in both clustered and non-clustered cases. Furthermore, these groups were not distributed in the same patterns among the clustered and non-clustered cases, but rather in distinct patterns. ^

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"Experimental Movie Project" (1945-46):; 1. "Below the Surface", Drehbuch des Testfilms, a) als Typoskript vervielfältigt, 46 Blatt, b) als Typoskript vervielfältigt, 26 Blatt, c) als Typoskript vervielfältigt, 26 Blatt, d) als Typoskript vervielfältigt, 26 Blatt "Experimental Movie Project" (1945-46): Memoranden zum Test; 2. 'Notes' 25.4.1946, Typoskript, 1 Blatt; 3. "Memorandum on Experimental Movie Project", 19.4.1946. Typoskript, 3 Blatt; 4. "Memorandum re: 'Below the Surface" (Juli 1945). Typoskript, 2 Blatt; 5. Dore Schary und Allen Rivkin: 'Memorandum, Subject: New Suggested Treatment for 'Below the Surface'", 13.7.1945. Typoskript, 2 Blatt; 6. Hans Richter: "Report about the film script 'Below the surface'", 7. u. 8.7.1945, a) Typoskript, 1 Blatt, b) Typoskript, 1 Blatt; 7. Hans Richter: Bestätigung der Vereinbarung mit dem American Jewish Committee, 3.7.1945. Typoskript, 1 Blatt; 8. "Notes and Suggestions re Experimental Motion Picture", Juni 1945. Typoskript, 2 Blatt; 9. Siegfried Kracauer; "Suggestions for the Dialogue" (4.4.1945). Typoskript, 3 Blatt; 10. "Motion Picture", März 1945. Typoskript, 5 Blatt; 11. "Project on a Test film", a) Typoskript, 4 Blatt, b) Typoskript, 5 Blatt; 12. "Memorandum re: 'Below the Surface'", a) Typoskript, 3 Blatt, b) Typoskript mit eigenhändigen Korrekturen von Theodor W. Adorno, 3 Blatt; "Experimental Movie Project" (1945-46): Korrespondenz zum Test-Film-Projekt:; 13. Friedrich Pollock: 1 Brief an Max Horkheimer, Santa Monica, California, 12.10.1945; 14. Theodor W. Adorno: 2 Briefe an Max Horkheimer, Los Angeles und Santa Monica, California, 1945; 15. Joseph M. Proskauer: 1 Brief von Max Horkheimer, o.O., 29.6.1945, 1 Brief mit Unterschrift an Max Horkheimer, o.O., o.D., 3 Blatt; 16. Alexander Hackenschmied, 1 Brief mit Unterschrift an Max Horkheimer, New York, 19.6.1945, 1 Blatt; 17. Gilbert Gabriel: 1 Brief von John Slawson, o.O., 22.3.1945, 2 Blatt; "The Police and Minority Groups" (1946):; 1. "The Police and Minority Groups". Typoskript, 2 Blatt; 2. Robert W. Kenny: "Police and Minority Groups - an Experiment". Als Typoskript vervielfältigt, 17 Blatt; 3. Davis McEntire, Robert B. Powers: "Police Training Bulletin. A Guide to Race Relations for Police Officers", State of California, 1946, 38 Seiten; Max Horkheimer: "Memorandum on a Study of Race Hatred in Post-War Germany" (1946):; 1. Memorandum, a) Typoskript, 8 Blatt, b) Typoskript mit eigenhändigen und handschriftlichen Korrekturen, 6 Blatt, c) Typoskript, 5 Blatt, d) Teilstück, Typoskript mit eigenhändigen Korrekturen, 1 Blatt e) Typoskript mit eigenhändigen Korrekturen, 5 Blatt, f) Teilstück, Typoskript mit handschriftlichen Korrekturen, 2 Blatt, g) Typoskript mit eigenhändigen Korrekturen, 7 Blatt, h) Teilstück, Typoskript mit eigenhändigen Korrekturen und Ergänzungen, 1 Blatt, i) Typoskript, 2 Blatt; 2. Theodor W. Adorno: "Ad Memorandum Neumann", Manuskript, 3 Blatt;