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Layrisse Z, Guedez Y, Domínguez E, Paz N, Montagnani S, Matos M, Herrera F, Ogando V, Balbas O, Rodríguez-Larralde A. Extended HLA haplotypes in a Carib Amerindian population: the Yucpa of the Perija Range. Hum Immunol 2001; 62:992-1000. [PMID: 11543901 DOI: 10.1016/s0198-8859(01)00297-x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Eleven MHC loci haplotypes have been defined among a Carib speaking Amerindian population; the Yucpa, inhabiting the northern section of the Perija Range, on the limits between Colombia and Venezuela. This tribe has been known with the name of "Motilones mansos" and is located close to the Chibcha-Paeze speaking Bari or "Motilones bravos." Seventy-three full blooded Yucpa living at the villages of Aroy, Marewa, and Peraya, were selected using a genealogy previously collected by an anthropologist and tested for Bf-C4AB complement allotypes and by serology, high resolution PCR-SSO and SBT typing for HLA class 1 and class 2 alleles. Combinations of 6 HLA-A, 6 HLA-B, 5 HLA-C, 1 Bf, 3 C4AB, 3 DQA1, 3DQB1 and 2 DPA1 and 2 DPB1 alleles present in this population originate 17 different haplotypes, 3 of which represent 63% of the haplotypic constitution of the tribe. The presence of 13 individuals homozygous for 11-loci haplotypes corroborates the existence of the following allelic combinations: DRB1*0411 DQA1*03011 DQB1*0302 DPA1*01 DPB1*0402 with HLA-A*6801 C*0702 B*3909 BfS C4 32 (f = 0.3372) or with A*0204 C*0702 B*3905 (f = 0.1977) and a third haplotype which differs only in DRB1*0403 and A*2402 (f = 0.0930). The results demonstrate the isolation of the tribe and the existence of high frequencies of a reduced number of "Amerindian" ancestral and novel class 1 and class 2 alleles (B*1522, DRB1*0807) with significant linkage disequilibria. These results will be useful to test the hypothesis that differentiation of Amerindian tribal groups will have to rely on haplotypes and micropolymorphism rather than allelic lineage frequencies due to the uniformity shown thus far by the putative descendants of the original Paleo-Indians.
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Affiliation(s)
- Z Layrisse
- From the Laboratorios de Fisiopatología y de Genetica Humana, Centro de Medicina Experimental, Instituto Venezolano de Investigaciones Cientificas, Caracas, Venezuela.
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102
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Casillas J, Cordón O, Del Jesus M, Herrera F. Genetic feature selection in a fuzzy rule-based classification system learning process for high-dimensional problems. Inf Sci (N Y) 2001. [DOI: 10.1016/s0020-0255(01)00147-5] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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103
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Cordón O, Herrera F, Magdalena L, Villar P. A genetic learning process for the scaling factors, granularity and contexts of the fuzzy rule-based system data base. Inf Sci (N Y) 2001. [DOI: 10.1016/s0020-0255(01)00143-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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104
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105
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Coronado C, Botello JE, Herrera F. Study and mathematical modeling of the production of propionic acid by Propionibacterium acidipropionici immobilized in a stirred tank fermentor. Biotechnol Prog 2001; 17:669-75. [PMID: 11485428 DOI: 10.1021/bp010059p] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A mathematical model was developed that describes production of propionic acid by fermentation of sweet whey with Propionibacterium acidipropionici immobilized in calcium polygalacturonate beads in a fermentor-type stirred tank. This mathematical model is constituted by a partial differential equations system, which fits consumption, production, growth and internal diffusion rates in the support. Fermentation was experimentally studied with free cells and immobilized cells, effective diffusivities of lactose and propionic acid were estimated in the support, and typical parameters of the model were obtained by nonlinear regression of the experimental data. The variance analysis shows that the combination of micro(max) and K(d) parameters is the source of variation most significative, also they were found to be the most sensitive parameters of the model. Finally, an effectiveness factor was calculated in order to assess the effect of mass transfer on the overall reaction rate observed.
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Affiliation(s)
- C Coronado
- Instituto Tecnológico de Celaya, Dep. de Ingeniería Química, Ave. Tecnológico y Antonio García Cubas, C.P. 38010, Celaya Gto. Mexico
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106
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Herrera F, Lopez A, Mascolo G, Albers P, Kiwi J. Catalytic decomposition of the reactive dye Uniblue A on hematite. Modeling of the reactive surface. Water Res 2001; 35:750-760. [PMID: 11228974 DOI: 10.1016/s0043-1354(00)00295-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Experimental results from the adsorption and subsequent catalytic combustion of the reactive dye Uniblue A on hematite indicate that this iron oxide can be used as an affordable catalyst for environmental purposes. Uniblue A was adsorbed on hematite and the products of the catalytic oxidation in O2 atmosphere were analyzed by thermal programmed gas-chromatography/mass spectrometry (STDS-GC-MS) analysis. The catalytic combustion of Uniblue A in the presence of hematite led to about 40% conversion of the dye C-content into CO2 at T = 275 degrees C. The activation energy (Ea) for the desorption of CO2 and other polyaromatic hydrocarbons (PAHs) from the hematite surface was determined to be 23.4 kcal mol-1. Identification of the species of Uniblue A in solution and those existing on the hematite surface was carried out in the framework of the generalized two-layer diffuse model. The modeling of the amount of dye absorbed on hematite is in good agreement with the experimental data.
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Affiliation(s)
- F Herrera
- Institute of Physical Chemistry II, EPFL, 1015 Lausanne, Switzerland
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107
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Layrisse Z, Fernandez MT, Montagnani S, Matos M, Balbas O, Herrera F, Colorado IA, Catalioti F, Acquatella H. HLA-C(*)03 is a risk factor for cardiomyopathy in Chagas disease. Hum Immunol 2000; 61:925-9. [PMID: 11053636 DOI: 10.1016/s0198-8859(00)00161-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Previous studies have shown the effect of class 1 as detected by serology or class 2 HLA genes by oligotyping upon susceptibility or resistance to the cardiomyopathy that develops in approximately one third of the Trypanosoma cruzi chronically infected patients. Low and intermediate resolution DNA typing of class 1 alleles was performed in a sample of 113 serologically positive individuals with and without cardiomyopathy. A polymerase chain reaction-sequence-specific oligonucleotide probe method using primers and probes from the British Society of Histocompatibility and Immunogenetics as modified for the VII Latin American Histocompatibility Workshop by D. Middleton, and LiPA kits from Innogenetics were used. Several alleles (A(*)11, A(*)31, B(*)15, B(*)35, B(*)45, B(*)49, B(*)51, and C(*)03) showed increased frequencies among patients with cardiac damage versus the asymptomatic group, but only the last one remained significant after correction of the p value (OR = 5.8, p(c) = 0.03). HLA-C(*)03 showed linkage disequilibrium with B(*)40 and B(*)15 and although both haplotypes were increased in cardiopathic patients compared with asymptomatic individuals, the difference is not significant. These results suggest that the HLA-C*03 allele could confer susceptibility to the development of cardiomyopathy among Venezuelan T. cruzi seropositive individuals and contrast with the protective effect conferred by the HLA B40 Cw3 haplotype among Chilean chagasic patients. Further studies will be needed to confirm the role of this allele on the cardiomyopathy of Chagas disease.
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Affiliation(s)
- Z Layrisse
- Instituto Venezolano de Investigaciones Científicas, Centro de Medicina Experimental, Laboratorio de Fisiopatología, Caracas, Venezuela.
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108
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109
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Rodríguez M, Ayala A, Rosa F, Herrera F, Rodríguez S, Díaz-González M. Portable data acquisition system for EKG measurements in marine environments. Comput Methods Programs Biomed 2000; 62:145-152. [PMID: 10764941 DOI: 10.1016/s0169-2607(00)00054-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In the present paper, an electronic prototype designed to acquire electrocardiographic signals from marine mammals has been developed. The system consists of a portable device that allows the on-line acquisition of EKG signals through a parallel port interface that is connected to a laptop computer. The EKG waveform, the voltage level, the bandwidth and the most relevant information from this type of signals is stored and analysed under real-time conditions by means of specifically implemented software. The whole system has been successfully tested to obtain the EKG from captive dolphins. The characteristics of the equipment presented here, with its low cost, size and energy requirements accomplish a portable system suitable for the acquisition of this type of signals in conductive media such as the seawater.
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Affiliation(s)
- M Rodríguez
- Department of Fundamental and Experimental Physics, University of La Laguna, 38203, La Laguna, Spain
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110
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Abstract
An in vitro translation system has been prepared from Plasmodium falciparum by saponin lysis of infected-erythrocytes to free parasites which were homogeneized with glass beads, centrifuged to obtain a S-30 fraction followed by Sephadex G-25 gel filtration. This treatment produced a system with very low contamination of host proteins (<1%). The system, optimized for Mg2+ and K+, translates endogenous mRNA and is active for 80 min which suggests that their protein factors and mRNA are quite stable.
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Affiliation(s)
- A Ferreras
- Centro de Investigaciones Biomédicas, Facultad de Ciencias de la Salud, Universidad de Carabobo, Maracay, Aragua, Venezuela
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111
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112
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113
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114
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115
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Herrera F, Lozano M, Verdegay JL. Dynamic and heuristic fuzzy connectives-based crossover operators for controlling the diversity and convergence of real-coded genetic algorithms. INT J INTELL SYST 1998. [DOI: 10.1002/(sici)1098-111x(199612)11:12<1013::aid-int1>3.0.co;2-q] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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118
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Borys RD, Lowenthal DH, Wetzel MA, Herrera F, Gonzalez A, Harris J. Chemical and microphysical properties of marine stratiform cloud in the North Atlantic. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98jd02087] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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119
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Martínez-Arends A, Layrisse Z, Argüello R, Herrera F, Montagnani S, Matos M, Ross J, Dunn P, Marsh SG, Madrigal JA. Characterization of the HLA class I genotypes of a Venezuelan Amerindian group by molecular methods. Tissue Antigens 1998; 52:51-6. [PMID: 9714474 DOI: 10.1111/j.1399-0039.1998.tb03023.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We have characterized the HLA class I genotypes of the Yucpa, a tribe of Venezuelan Amerindians, using molecular methods. The study was carried out on DNA extracted from unrelated individuals using low resolution ARMS-SSP typing with sequence-specific primers, high resolution typing using reference strand conformation analysis (RSCA), and for some samples sequence-based typing (SBT). The following class I alleles were found to be present in this tribe: for the HLA-A locus A*0204, A*0212, A*0213, A*2402, A*3101 and A*6801; for the B locus B*1522, B*3512, B*3905, B*3909, B*4004 and B*52012, and for C locus Cw*0102, Cw*0302/ 4, Cw*0401, Cw*0702 and Cw*1503. This is the first time these alleles have been described in this group, although all of them have previously been reported as being present in other Amerindian tribes. The study confirmed the high frequency of HLA-B39 which was previously observed in serological analysis of this tribe, and indicated that two different B*39 alleles were present in this population. The identification of the class I alleles by molecular methods for this ethnic group confirms the restricted polymorphism of the MHC molecules previously obtained by serology and has allowed a more accurate definition of the different alleles present in this population.
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Affiliation(s)
- A Martínez-Arends
- Centro de Medicina Experimental, Instituto Venezolano de Investigaciones Científicas, Caracas
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120
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121
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Fernandez-Mestre MT, Layrisse Z, Montagnani S, Acquatella H, Catalioti F, Matos M, Balbas O, Makhatadze N, Dominguez E, Herrera F, Madrigal A. Influence of the HLA class II polymorphism in chronic Chagas' disease. Parasite Immunol 1998; 20:197-203. [PMID: 9618730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Chagas' disease or American trypanosomiasis due to Trypanosoma cruzi has existed at least since the time of the Inca empire and contributes significantly to cardiovascular morbidity and mortality in several countries of this continent. Due to the fundamental role of human class II molecules polymorphic residues in the control of the immune response, a study was designed to define by DNA typing HLA class II alleles in a sample of 67 serologically positive individuals with and without cardiomyopathy and in 156 healthy controls of similar ethnic origin. Genomic DNA extraction, PCR amplification of the HLA-DRB1 and DQB1 second exon regions and hybridization to labelled specific probes were carried out following the 11th International Histocompatibility Workshop reference protocol. Comparison of DRB1 and DQB1 allele frequencies among the patients and control subjects showed a decreased frequency of DRB1*14 and DQB1*0303 in the patients, suggesting independent protective effects to the chronic infection in this population. Allele frequencies comparison between patients with and without cardiomyopathy showed a higher frequency of DRB1*01, DRB1*08 and DQB1*0501 and a decreased frequency of DRB1*1501 in the patients with arrhythmia and congestive heart failure. The results suggest that HLA Class II genes may be associated with the development of a chronic infection and with heart damage in Chagas' disease.
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122
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Cordón O, Del Jesús M, Herrera F, Lozano M. Modelado cualitativo utilizando una metodología evolutiva de aprendizaje iterativo de bases de reglas difusas. Int Artif 1998. [DOI: 10.4114/ia.v2i5.680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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123
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124
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Gorodezky C, Olivo A, Alaez C, Vázquez MN, de la Rosa G, Debaz H, Robles C, Altamirano N, Layrisse Z, Balducci PL, Domínguez E, Herrera F, Montagnani S, Esparza B, Balbas O, Gunczler P, Lanes R, Amaro R, Zaro R, Fuenmayor V, Montoya F, Bedoya CI, Restrepo MC, Villegas A, Vicario JL. [High- and low-risk molecular sequences in autoimmune diseases. An analysis of type I diabetes in Latin America]. GAC MED MEX 1998; 133 Suppl 1:125-32. [PMID: 9504114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Type I diabetes is an autoimmune and a polygenic disease, in which MHC-class II genes contribute to 48% of the disease. The aim of the present study, is to provide a guideline to understanding the molecular association of these genes, through the immunogenetic analysis of 3 Latin american mestizo populations. We included 606 individuals, 349 patients with DMDI and 257 healthy controls coming from 3 geographical areas: Mexico City, Mexico; Caracas, Venezuela and Medellin, Colombia. The results clearly indicate that in mestizo groups, the diabetogenic haplotypes are from mediterranean ancestry, while protection is due to Amerindian genes. It was demonstrated that the relevant sequences for IDDM expression are located to DRB1 and DQB1 loci with a minimal contribution of DQA1 residues. The sequences determining peptide recognition and the induction of TH1 cells mediating the cellular autoimmune response are in positions DRB1-57 and 74 (an aspartic acid and a glutamic acid respectively, confer protection), modulated by D-57 in the DQ, 8 chain. These data show that DRB1-DQB1 haplotypes are central for IDDM expression and open new pathways for the disease management.
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Affiliation(s)
- C Gorodezky
- Departamento de Inmunogenética, INDRE, SSA, MEXICO D.F. cgorodeaUmailer.main.conacyt.mx
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125
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Attwood GT, Herrera F, Weissenstein LA, White BA. Retraction: An endo-beta-1,4-glucanase gene (celA) from the rumen anaerobe Ruminococcus albus 8: cloning, sequencing, and transcriptional analysis. Can J Microbiol 1998; 44:312. [PMID: 9643967 DOI: 10.1139/cjm-44-3-312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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126
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Gutiérrez R, Cederlund E, Hjelmqvist L, Peirano A, Herrera F, Ghosh D, Duax W, Jörnvall H, Eyzaguirre J. Acetyl xylan esterase II from Penicillium purpurogenum is similar to an esterase from Trichoderma reesei but lacks a cellulose binding domain. FEBS Lett 1998; 423:35-8. [PMID: 9506837 DOI: 10.1016/s0014-5793(98)00055-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Penicillium purpurogenum produces at least two acetyl xylan esterases (AXE I and II). The AXE II cDNA, genomic DNA and mature protein sequences were determined and show that the axe 2 gene contains two introns, that the primary translation product has a signal peptide of 27 residues, and that the mature protein has 207 residues. The sequence is similar to the catalytic domain of AXE I from Trichoderma reesei (67% residue identity) and putative active site residues are conserved, but the Penicillium enzyme lacks the linker and cellulose binding domain, thus explaining why it does not bind cellulose in contrast to the Trichoderma enzyme. These results point to a possible common ancestor gene for the active site domain, while the linker and the binding domain may have been added to the Trichoderma esterase by gene fusion.
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Affiliation(s)
- R Gutiérrez
- Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Casilla, Santiago
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128
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Cordón O, Herrera F. A three-stage evolutionary process for learning descriptive and approximate fuzzy-logic-controller knowledge bases from examples. Int J Approx Reason 1997. [DOI: 10.1016/s0888-613x(96)00133-8] [Citation(s) in RCA: 147] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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129
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Abstract
The cytotoxicity of a low mol. wt fraction (LMWF) obtained from Aloe vera gel was determined by two different assays. Firstly, exposure of monolayers of chicken fibroblasts to LMWF induced disruption of intercellular junctions and detachment of individual cells from the bottom of the flask, with formation of cell-free gaps in the monolayer. Secondly, LMWF inhibited the production of reactive oxygen species by human polymorphonuclear leukocytes stimulated by zymosan, as followed by luminol-dependent chemiluminescence. The toxic activity of LMWF was compared to that of sodium dodecyl sulfate (a well-known toxic substance), aloe-emodin and aloin (an anthraquinone and its precursor present in Aloe vera cortex) using the chemilumescence assay, and was found to be of similar potency to these toxic substances on a weight-to-weight basis. These results confirm that Aloe vera gel contains toxic low mol. wt compounds, and every effort must be made to limit the amount of these toxins in the commercially prepared Aloe vera gel products.
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Affiliation(s)
- H Avila
- Centro de Investigaciones Biomédicas (BIOMED), Facultad de Ciencias de la Salud, Universidad de Carabobo, Maracay, Venezuela
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130
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Triana L, Ferreras AC, Cayama E, Correia H, Fraile G, Chakraburtty K, Herrera F. Involvement of a 50-kDa mRNP protein from Saccharomyces cerevisiae in mRNA binding to ribosomes. Arch Biochem Biophys 1997; 344:1-10. [PMID: 9244375 DOI: 10.1006/abbi.1997.0173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A yeast 50-kDa mRNA-binding protein (50mRNP) is found selectively associated with the 48S and 80S initiation complexes. This protein is structurally related to the translational elongation factor EF-1alpha. The protein reacts with antibodies directed against EF-1alpha and, similarly, EF-1alpha recognizes antibodies against the 50mRNP protein. This is evidence that they share at least one epitope which allows a similar antigenic behavior. In addition, both proteins show similar cleavage patterns upon treatment with the endoproteinase Lys-C. A murine antibody raised against 50mRNP inhibits both 48S and 80S initiation complex formation. The inhibitory effect is relieved by preincubating anti-50mRNP with EF-1alpha. Antibody to EF-1alpha manifests a similar inhibitory pattern for the formation of 48S and 80S complexes. These data strongly suggest that 50mRNP is an EF-1alpha-like polypeptide essential for the formation of the above complexes.
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Affiliation(s)
- L Triana
- Centro de Investigaciones Biomédicas (BIOMED), Facultad de Ciencias dela Salud, Universidad de Carabobo, Maracay, Venezuela
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Affiliation(s)
- H Correia
- Centro de Investigaciones Biomédicas (BIOMED), Facultad de Ciencias de la Salud, Universidad de Carabobo, Maracay, Venezuela
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132
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Herrera F, Herrera-Viedma E, Verdegay J. Linguistic measures based on fuzzy coincidence for reaching consensus in group decision making. Int J Approx Reason 1997. [DOI: 10.1016/s0888-613x(96)00121-1] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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133
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Abstract
Nucleotide sequences of five novel HLA-DRB1*08 alleles have been recently reported but their frequency in different populations is still unknown. The presence of DRB1*08 variants among Carib-speaking Yucpa Amerindians of the Perijá Range in the border between Colombia and Venezuela was tested by PCR-DNA typing. DRB1*0807 was the only DRB1*08 variant found in this population with a frequency of 0.1250. Until very recently, DRB1*0802 was the predominant DRB1*08 allele present among full-blooded Amerindians, but in the last 3 years DRB1*0804 has been found in 2 South American tribes and *0811 in 2 North American tribes. The description of a new functional DRB1*08 variant in Amerindians suggests that extensive gene polymorphism among Amerindians might not be limited to the HLA-B Class I locus.
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Affiliation(s)
- Z Layrisse
- Centro de Medicina Experimental, Instituto Venezolano de Investigaciones Cientificas, Caracas, Venezuela.
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134
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Cordón O, Herrera F, Lozano M. A CLASSIFIED REVIEW ON THE COMBINATION FUZZY LOGIC–GENETIC ALGORITHMS BIBLIOGRAPHY: 1989–1995. Advances in Fuzzy Systems — Applications and Theory 1997. [DOI: 10.1142/9789814261296_0012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- O. Cordón
- Dept. of Computer Science and Artificial Intelligence, E.T.S.I. Informatica. Universidad de Granada. 18071, Granada, Spain
| | - F. Herrera
- Dept. of Computer Science and Artificial Intelligence, E.T.S.I. Informatica. Universidad de Granada. 18071, Granada, Spain
| | - M. Lozano
- Dept. of Computer Science and Artificial Intelligence, E.T.S.I. Informatica. Universidad de Granada. 18071, Granada, Spain
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136
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Herrera F, Lozano M, Verdegay JL. Dynamic and heuristic fuzzy connectives‐based crossover operators for controlling the diversity and convergence of real‐coded genetic algorithms. INT J INTELL SYST 1996. [DOI: 10.1002/(sici)1098-111x(199612)11:12<1013::aid-int1>3.3.co;2-k] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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137
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Domínguez E, Herrera F, Balducci P, Montagnani S, Layrisse Z. MHC studies in ethnically-mixed families with IDDM. Hum Immunol 1996. [DOI: 10.1016/0198-8859(96)85540-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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138
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Attwood GT, Herrera F, Weissenstein LA, White BA. An endo-beta-1,4-glucanase gene (celA) from the rumen anaerobe Ruminococcus albus 8: cloning, sequencing, and transcriptional analysis. Can J Microbiol 1996; 42:267-78. [PMID: 8868234 DOI: 10.1139/m96-039] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A genomic library of Ruminococcus albus 8 DNA was constructed in Escherichia coli using bacteriophage lambda ZapII. This library was screened for cellulase components and several Ostazin brilliant red/carboxymethyl cellulose positive clones were isolated. All of these clones contained a common 3.4-kb insert, which was recovered as a plasmid by helper phage excision. The carboxymethyl cellulase coding region was localized to a 1.4-kb region of DNA by nested deletions, and a clone containing the entire celA gene was sequenced. Analysis of the sequence revealed a 1231-bp open reading frame, coding for a protein of 411 amino acids with a predicted molecular weight of 45 747. This protein, designated CelA, showed extensive homology with family 5 endoglucanases by both primary amino acid sequence alignment and hydrophobic cluster analysis. Cell-free extracts of E. coli containing the celA clone demonstrated activity against carboxymethyl cellulose and acid swollen cellulose but not against any of the p-nitrophenol glycosides tested, indicating an endo-beta-1,4-glucanase type of activity. In vitro transcription-translation experiments showed that three proteins of 48,000, 44,000, and 23,000 molecular weight were produced by clones containing the celA gene. Northern analysis of RNA extracted from R. albus 8 grown on cellulose indicated a celA transcript of approximately 2700 bases, whereas when R. albus 8 was grown on cellobiose, celA transcripts of approximately 3000 and 600 bases were detected. Primer extension analysis of these RNAs revealed different transcription initiation sites for the celA gene when cells were grown with cellulose or cellobiose as the carbon source. These two sites differed by 370 bases in distance. A model, based on transcription and sequence data, is proposed for celA regulation.
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Affiliation(s)
- G T Attwood
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, 61801, USA
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Martínez R, Estrada MP, Berlanga J, Guillén I, Hernández O, Cabrera E, Pimentel R, Morales R, Herrera F, Morales A, Piña JC, Abad Z, Sánchez V, Melamed P, Lleonart R, de la Fuente J. Growth enhancement in transgenic tilapia by ectopic expression of tilapia growth hormone. Mol Mar Biol Biotechnol 1996; 5:62-70. [PMID: 8869518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The generation of transgenic fish with the transfer of growth hormone (GH) genes has opened new possibilities for the manipulation of growth in economically important fish species. The tilapia growth hormone (tiGH) cDNA was linked to the human cytomegalovirus (CMV) enhancer-promoter and used to generate transgenic tilapia by microinjection into one-cell embryos. Five transgenic tilapia were obtained from 40 injected embryos. A transgenic animal containing one copy of the transgene per cell was selected to establish a transgenic line. The transgene was stably transmitted to F1 and F2 generations in a Mendelian fashion. Ectopic, low-level expression of tiGH was detected in gonad and muscle cells of F1 transgenic tilapia by immunohystochemical analysis of tissue sections. Nine-month-old transgenic F1 progeny were 82% larger than nontransgenic fish at p = .001. These results showed that low-level ectopic expression of tiGH resulted in a growth acceleration in transgenic tilapia. Tilapia GH gene transfer is an alternative for growth acceleration in tilapia.
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Affiliation(s)
- R Martínez
- Mammalian Cell Genetics Division, Centro de Ingeniería Genética y Biotechnologia, Havana, Cuba
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140
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Layrisse Z, Guedez Y, Dominguez E, Herrera F, Soto M, Balbas O, Matos M, Alfonzo JC, Granados J, Scorza J. Extended HLA haplotypes among the Bari Amerindians of the Perija Range. Relationship to other tribes based on four-loci haplotype frequencies. Hum Immunol 1995; 44:228-35. [PMID: 8770636 DOI: 10.1016/0198-8859(95)00111-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Extended HLA haplotypes among Bari Amerindians living at the Perija Range on the limits between Colombia and Venezuela have been defined using serology for class I, electrophoresis and immuno-fixation for Bf and C4, and PCR-SSO for class II loci typing. Haplotypes were assigned based on family studies and gene frequencies were calculated using a subset of less related subjects selected from the genealogy. No rare class III variants were observed, but the characteristic low HLA diversity of isolated Amerindians populations present also in the Bari extends to Bf and C4. Thus there were only 22 different haplotypes segregating in families when nine loci were considered. All of them except three carried Bf*S, C4A*3, C4B*1. The null allele C4A*Q0 reached a frequency of 0.147 and was predominantly present in A24 Cw7 B39 DRB1*0411 haplotypes. In contrast to what has been reported using HLA alleles or class I haplotype frequencies and other isolated South American tribes, genetic distance estimates based on A-Cw-B-DR haplotype frequencies show a closer relationship between the two linguistically but geographically distant Venezuelan tribes, the Bari and the Warao, as compared to two culturally different Brazilian populations. The information reported here will be useful for identifying ancestral haplotypes in native peoples of America, for population comparison, and for discussing the differential influence of MHC haplotype diversity and population survival when similar data on other Amerindian tribes becomes available.
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Affiliation(s)
- Z Layrisse
- Venezuelan Institute for Scientific Investigations, School of Bioanalysis, Caracas, Venezuela
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141
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Martínez-vidal JL, Parrilla P, Fernández-alba AR, Carreñ R, Herrera F. A New Sequential Procedure for the Efficient and Automated Location of Optimum Conditions in High Performance Liquid Chromatography (HPLC). ACTA ACUST UNITED AC 1995. [DOI: 10.1080/10826079508010427] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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142
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143
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Layrisse Z, Guedez Y, Dominguez E, Herrera F. DP allele and haplotype frequencies among 2 linguistically related South American Indian Tribes. Hum Immunol 1994. [DOI: 10.1016/0198-8859(94)91813-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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144
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145
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Herrera F, Correia H, Triana L, Fraile G. Association of ribosomal subunits. A new functional role for yeast EF-1 alpha in protein biosynthesis. Eur J Biochem 1991; 200:321-7. [PMID: 1889401 DOI: 10.1111/j.1432-1033.1991.tb16188.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A yeast ribosomal subunit association factor (AF) has been purified from a high-salt ribosomal wash. The purified enzyme is a thermostable protein that associates ribosomal subunits at low Mg2+ concentration without requiring energy. It appears to be an aggregate of trimers or dimers (molecular mass 125 or 79 kDa) which on sodium dodecyl sulfate gels shows the presence of a major protein band whose estimated molecular mass is 43 kDa. Evidence also indicates the existence of a 50-kDa polypeptide which seems to be unstable since with freezing and thawing it gives rise to the 43-kDa polypeptide. It was shown that the labelled factor interacts with 80S ribosomes and with 40S ribosomal subunits. The purified polypeptide reacts with antibodies directed against EF-1 alpha, this last protein recognizing the antibodies raised against AF. Likewise, both EF-1 alpha and AF associate ribosomal subunits in the same way. When EF-1 is heated, it not only maintains its association activity, but also behaves like a 43-kDa polypeptide in an SDS electrophoresis run. These observations strongly suggest that AF originates from EF-1 alpha, which implies that the well-known elongation factor may also play a role in the initiation step of protein synthesis.
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Affiliation(s)
- F Herrera
- Centro de Investigaciones Biomédicas (BIOMED), Facultad de Ciencias de la Salud, Universidad de Carabobo, Venezuela
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146
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Aliaga L, Herrera F, Sarmiento C, Plaza F, Castillo A. [Chylous ascites secondary to a carcinoid tumor]. An Med Interna 1990; 7:419-21. [PMID: 2103270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A 68-year-old male with abdominal swelling and wasting of one month's evolution had chylous ascites. The clinical study of the patient showed a retroperitoneal tumor and a distal jejunum and mesenterium affliction. There were metastatic nodules in peritoneum, epiploic appendix and malignant pleural effusion. The histological study showed a carcinoid tumor. Chylous ascites is an exceptional complication, and a bad prognosis factor of carcinoid tumor.
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Affiliation(s)
- L Aliaga
- Servicio de Medicina Interna, Hospital de la Cruz Roja del INSALUD, Ceuta
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Abstract
The polysomal mRNA from the cell-free system of the yeast Saccharomyces cerevisiae, in the absence of exogenous energy, binds to the 40S ribosomal subunit thus forming a 48S preinitiation complex which, with energy added, is converted into 80S initiation complex. By using ribosomes with a high affinity to polysomal mRNA (pmRNA) from an edeine-resistant mutant of S. cerevisiae in place of wild-type ribosomes, increased quantities of the 48S preinitiation complex are obtained. The pmRNA is found associated with several polypeptides having molecular masses of 115-98 kDa, 72 kDa, 60 kDa and 51 kDa. These polypeptides, labelled with 125I, interact with 40S and 80S ribosomes and are essential for the formation of the 48S and 80S initiation complexes inasmuch as deproteinized pmRNA alone cannot initiate the process. In addition, other polypeptides present in the cytosol are required to carry out the above-mentioned steps of protein synthesis.
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Affiliation(s)
- F Herrera
- Centro de Investigaciones Biomédicas (BIOMED), Facultad de Ciencias de la Salud, Universidad de Carabobo, Maracay-Aragua, Venezuela
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149
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Palomo I, Valdés E, León M, Herrera F, Ramos L, Rojas A, Pino M. [Typhoid and paratyphoid fevers in the province of Talca, Chile]. Rev Med Chil 1988; 116:180-3. [PMID: 3148182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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150
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