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Fleming ST, Pearce KA, McDavid K, Pavlov D. The development and validation of a comorbidity index for prostate cancer among Black men. J Clin Epidemiol 2003; 56:1064-75. [PMID: 14614997 DOI: 10.1016/s0895-4356(03)00213-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
BACKGROUND AND OBJECTIVES The purpose of this study was to develop a comorbidity index specific to Black Men with prostate cancer, because certain comorbidities and prostate cancer are particularly prevalent among this racial group. METHODS This research used the Surveillance, Epidemiology, and End Results (SEER)-Medicare-linked database to develop an index of comorbidity burden based on survival, and the presence/absence of comorbid illness in 2,931 Black males diagnosed with prostate cancer. Comorbidity burden was recognized using inpatient, outpatient, and physician claims for a 2-year period prior to the diagnosis of prostate cancer. We compared five different statistical models, each with two-way, three-way, and/or four-way interactions among the comorbidities, and selected the model with only two-way interactions as the optimal choice. We demonstrated the utility of refining the simplest model, with 27 comorbidity categories only, by adjusting for the number of different diagnoses within statistically significant categories.
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McDavid KA, Fleming ST, Pearce KA, Pavlov D. #117 Predictors of treatment for black and white men at least 67 years old with prostate cancer. Ann Epidemiol 2002. [DOI: 10.1016/s1047-2797(02)00405-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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53
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Pereira JS, Pavlov D, Nili M, Greaser M, Homsher E, Moss RL. Kinetic differences in cardiac myosins with identical loop 1 sequences. J Biol Chem 2001; 276:4409-15. [PMID: 11076938 DOI: 10.1074/jbc.m006441200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The kinetics of nucleotide turnover vary considerably among isoforms of vertebrate type II myosin, possibly due to differences in the rate of ADP release from the nucleotide binding pocket. Current ideas about likely mechanisms by which ADP release is regulated have focused on the hyperflexible surface loops of myosin, i.e. loop 1 (ATPase loop) and loop 2 (actin binding loop). In the present study, we investigated the kinetic properties of rat and pig beta-myosin heavy chains (beta-MHC) in which we have found the sequences of loop 1 (residues 204-216) to be virtually identical, i.e. DQSKKDSQTPKG, with a single conservative substitution (rat E210D pig). Pig myocardium normally expresses 100% beta-MHC, whereas rat myocardium was induced to express 100% beta-MHC by surgical thyroidectomy and subsequent treatment with propylthiouracil. Slack test measurements at 15 degrees C yielded unloaded shortening velocities of 1.1 +/- 0.8 muscle lengths/s in rat skinned ventricular myocytes and 0.35 +/- 0.05 muscle lengths/s in pig skinned myocytes. Similarly, solution measurements at the same temperature showed that actin-activated ATPase activity was 2.9-fold greater for rat beta-myosin than for pig beta-myosin. Stopped-flow methods were then used to assess the rates of acto-myosin dissociation by MgATP both in the presence and absence of MgADP. Although the rates of MgATP-induced dissociation of acto-heavy meromyosin (acto-HMM) were virtually identical for the two myosins, the rate of ADP dissociation was approximately 3.8-fold faster for rat beta-myosin (135 s(-)(1)) than for pig beta-myosin (35 s(-)(1)). ATP cleavage rates were nearly 30% faster for rat beta-myosin. Thus, whereas loop 1 appears from other studies to be involved in nucleotide turnover in the pocket, our results show that loop 1 does not account for large differences in turnover kinetics in these two myosin isoforms. Instead, the differences appear to be due to sequence differences in other parts of the MHC backbone.
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Guachalla J, Czischke C, Lemus J, Barrera A, Soler T, Barahona R, Meneses M, Orlandi L, Rodriguez P, Pavlov D, Prats R, Fau C, Rosas R, Salas F. Lung Cancer in Chile. The importance of registering lung cancer patients for surgical treatment. Lung Cancer 2000. [DOI: 10.1016/s0169-5002(00)80519-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Homsher E, Lee DM, Morris C, Pavlov D, Tobacman LS. Regulation of force and unloaded sliding speed in single thin filaments: effects of regulatory proteins and calcium. J Physiol 2000; 524 Pt 1:233-43. [PMID: 10747195 PMCID: PMC2269863 DOI: 10.1111/j.1469-7793.2000.00233.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
1. Measurements of the unloaded sliding speed of and isometric force exerted on single thin filaments in in vitro motility assays were made to evaluate the role of regulatory proteins in the control of unloaded thin filament sliding speed and isometric force production. 2. Regulated actin filaments were reconstituted from rabbit F-actin, native bovine cardiac tropomyosin (nTm), and either native bovine cardiac troponin (nTn), troponin containing a TnC mutant, CBMII, in which the sole regulatory site in cardiac TnC (site II) is inactivated (CBMII-Tn), or troponin containing a point mutation in TnT (I79N, where isoleucine at position 79 is replaced with asparagine) associated with familial hypertrophic cardiomyopathy (FHC). 3. Addition of regulatory proteins to the thin filament increases both the unloaded sliding speed and the isometric force exerted by myosin heads on the thin filaments. 4. Variation of thin filament activation by varying [Ca2+] or the fraction of CBMII/TnC bound to the thin filament at pCa 5, had little effect on the unloaded filament sliding speed until the fraction of the thin filament containing calcium bound to TnC was less than 0.15. These results suggest that [Ca2+] primarily affects the number of attached and cycling crossbridges. 5. The presence of the FHC TnT mutant increased the thin filament sliding speed but reduced the isometric force that heavy meromyosin exerted on regulated thin filaments. These latter results, together with the increased sliding speed and isometric force seen in the presence of regulatory proteins, suggest that thin filament regulatory proteins exert significant allosteric effects on the interaction of crossbridges with the thin filament.
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Stoev SD, Anguelov G, Ivanov I, Pavlov D. Influence of ochratoxin A and an extract of artichoke on the vaccinal immunity and health in broiler chicks. EXPERIMENTAL AND TOXICOLOGIC PATHOLOGY : OFFICIAL JOURNAL OF THE GESELLSCHAFT FUR TOXIKOLOGISCHE PATHOLOGIE 2000; 52:43-55. [PMID: 10779152 DOI: 10.1016/s0940-2993(00)80014-7] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
The combined effect of ochratoxin A (at diet levels of 130, 305 and 790 ppb) and penicillic acid was studied in 100 broiler chicks. Serological investigations revealed significantly lower haemagglutination inhibiting antibody titers in the experimental chicks immunized with vaccine against Newcastle disease. A statistically significant decrease of the body weight and the relative weight of lymphoid organs as well as a significant increase of the relative weight of kidneys and liver were seen. The main degenerative changes were observed in the proximal convoluted tubules in kidneys and slight degenerative changes were found in the hepatocytes. Degenerative changes and depletion of lymphoid cells were observed in the bursa Fabricii, thymus, spleen and Peyer's patches of intestinal mucosa. Serum analyses revealed significant decreases of the total protein and cholesterol, and significant increases of the uric acid and glucose. Haematological analyses showed a slight anaemia, leucocytosis and slightly decompensated metabolic acidosis. A statistically significant protective effect of 5% total water extract of artichoke on humoral immune response (increase of haemaglutination inhibiting antibody titer), relative organ weight as well as on pathomorphological, haematological and biochemical changes induced by ochratoxin A, was established.
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Hansen JE, Marner J, Pavlov D, Rubenstein PA, Reisler E. Structural transition at actin's N-terminus in the actomyosin cross-bridge cycle. Biochemistry 2000; 39:1792-9. [PMID: 10677229 DOI: 10.1021/bi991873c] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Force and motion generation by actomyosin involves the cyclic formation and transition between weakly and strongly bound complexes of these proteins. Actin's N-terminus is believed to play a greater role in the formation of the weakly bound actomyosin states than in the formation of the strongly bound actomyosin states. It has been the goal of this project to determine whether the interaction of actin's N-terminus with myosin changes upon transition between these two states. To this end, a yeast actin mutant, Cys-1, was constructed by the insertion of a cysteine residue at actin's N-terminus and replacement of the C-terminal cysteine with alanine. The N-terminal cysteine was labeled stoichiometrically with pyrene maleimide, and the properties of the modified mutant actin were examined prior to spectroscopic measurements. Among these properties, actin polymerization, strong S1 binding, and the activation of S1 ATPase by pyrenyl-Cys-1 actin were not significantly different from those of wild-type yeast actin, while small changes were observed in the weak S1 binding and the in vitro motility of actin filaments. Fluorescence changes upon binding of S1 to pyrenyl-Cys-1 actin were measured for the strongly (with or without ADP) and weakly (with ATP and ATPgammaS) bound acto-S1 states. The fluorescence increased in each case, but the increase was greater (by about 75%) in the presence of MgATP and MgATPgammaS than in the rigor state. This demonstrates a transition at the S1 contact with actin's N-terminus between the weakly and strongly bound states, and implies either a closer proximity of the pyrene probe on Cys-1 to structural elements on S1 (most likely the loop of residues 626-647) or greater S1-induced changes at the N-terminus of actin in the weakly bound acto-S1 states.
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Tobacman LS, Lin D, Butters C, Landis C, Back N, Pavlov D, Homsher E. Functional consequences of troponin T mutations found in hypertrophic cardiomyopathy. J Biol Chem 1999; 274:28363-70. [PMID: 10497196 DOI: 10.1074/jbc.274.40.28363] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Missense mutations in the cardiac thin filament protein troponin T (TnT) are a cause of familial hypertrophic cardiomyopathy (FHC). To understand how these mutations produce dysfunction, five TnTs were produced and purified containing FHC mutations found in several regions of TnT. Functional defects were diverse. Mutations F110I, E244D, and COOH-terminal truncation weakened the affinity of troponin for the thin filament. Mutation DeltaE160 resulted in thin filaments with increased calcium affinity at the regulatory site of troponin C. Mutations R92Q and F110I resulted in impaired troponin solubility, suggesting abnormal protein folding. Depending upon the mutation, the in vitro unloaded actin-myosin sliding speed showed small increases, showed small decreases, or was unchanged. COOH-terminal truncation mutation resulted in a decreased thin filament-myosin subfragment 1 MgATPase rate. The results indicate that the mutations cause diverse immediate effects, despite similarities in disease manifestations. Separable but repeatedly observed abnormalities resulting from FHC TnT mutations include increased unloaded sliding speed, increased or decreased Ca(2+) affinity, impairment of folding or sarcomeric integrity, and decreased force. Enhancement as well as impairment of contractile protein function is observed, suggesting that TnT, including the troponin tail region, modulates the regulation of cardiac contraction.
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Iantcheva N, Steingass H, Todorov N, Pavlov D. A comparison of in vitro rumen fluid and enzymatic methods to predict digestibility and energy value of grass and alfalfa hay. Anim Feed Sci Technol 1999. [DOI: 10.1016/s0377-8401(99)00037-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Djouvinov D, Pavlov D, Ilchev A, Enev E. Peppermint (Mentha piperita Huds.) and basil (Ocimum basilicum L.) etheric oil by-products as roughages for sheep feeding. Anim Feed Sci Technol 1997. [DOI: 10.1016/s0377-8401(97)00048-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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62
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Atanassova S, Pavlov D, Todorov N. Estimation of chemical composition, net energy
and protein value of lucerne by NIRS
and by regression equation based of the days
of vegetation or the accumulated temperature. JOURNAL OF ANIMAL AND FEED SCIENCES 1994. [DOI: 10.22358/jafs/69846/1994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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63
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64
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Bojinov M, Pavlov D. Anodic oxidation of antimony at high overpotentials — formation of a barrier layer and klebelsbergite. J Electroanal Chem (Lausanne) 1993. [DOI: 10.1016/0022-0728(93)85023-a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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65
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Bojinov M, Pavlov D. The processes of formation of a gel-like anodic layer during polarization of an antimony electrode in H2SO4 solution. ACTA ACUST UNITED AC 1991. [DOI: 10.1016/0022-0728(91)80070-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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66
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Pavlov D, Monahov B, Sundholm G, Laitinen T. The effect of antimony on the anodic behaviour of lead in H2SO4 solution. ACTA ACUST UNITED AC 1991. [DOI: 10.1016/0022-0728(91)85202-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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67
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Pavlov D, Bojinov M, Laitinen T, Sundholm G. Electrochemical behaviour of the antimony electrode in sulphuric acid solutions—II. Formation and properties of the primary anodic layer. Electrochim Acta 1991. [DOI: 10.1016/0013-4686(91)85214-r] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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68
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Pavlov D, Bojinov M, Laitinen T, Sundholm G. Electrochemical behaviour of the antimony electrode in sulphuric acid solutions—I. Corrosion processes and anodic dissolution of antimony. Electrochim Acta 1991. [DOI: 10.1016/0013-4686(91)85213-q] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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69
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Laitinen T, Salmi K, Sundholm G, Monghov B, Pavlov D. The effect of antimony on the anodic behaviour of lead in sulphuric acid solutions—I. Voltammetric measurements. Electrochim Acta 1991. [DOI: 10.1016/0013-4686(91)85147-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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70
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Pavlov D, Pashmakova I. Influence of the size of PbSO4 crystals on their solubility and the significance of this process in the lead-acid battery. J APPL ELECTROCHEM 1987. [DOI: 10.1007/bf01024373] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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71
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Pavlov D, Ignatova S. ?Breathing? of the lead-acid battery negative plate during cycling. J APPL ELECTROCHEM 1987. [DOI: 10.1007/bf01007806] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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72
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Pavlov D, Rogachev T. Mechanism of the action of Ag and As on the anodic corrosion of lead and oxygen evolution at the Pb/PbO(2−x)/H2O/O2/H2SO4 electrode system. Electrochim Acta 1986. [DOI: 10.1016/0013-4686(86)87115-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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73
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Dimitrov M, Kochev K, Pavlov D. The effect of thickness and stoichiometry of the PbO layer upon the photoelectric properties of the Pb/PbO/PbSO4/H2SO4 electrode. ACTA ACUST UNITED AC 1985. [DOI: 10.1016/0368-1874(85)85487-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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74
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Beloev I, Elenkova A, Pavlov D. [Urinary catecholamine excretion and cardiac output in hypertensive patients]. VUTRESHNI BOLESTI 1982; 21:85-91. [PMID: 7101894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Cardiac output was determined to 70 patients with hypertonic disease I, II and III stage by dye-dilution method and urine excretion of adrenaline and noradrenaline was determined by fluorescence method. The extent of stroke and minute volume was determined depending on the stage of the disease, degree of arterial hypertension and patients' age. Noradrenaline excretion was normal in 75.8 per cent from the whole group of the patients examined and decreased in 24.2 per cent. Adrenaline excretion was increased in 7.1 per cent and with normal values--in 92.9 per cent of the patients. No discrepancies in adrenaline and noradrenaline excretion were found in the patients with hypertonic disease, depending both on the degree of arterial hypertension and patients' age. A moderate positive correlation was found between noradrenaline excretion and cardiac index and stroke index.
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Pavlov D. Semiconductor mechanism of the processes during electrochemical oxidation of PbO to PbO2. ACTA ACUST UNITED AC 1981. [DOI: 10.1016/s0022-0728(81)80539-6] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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