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1.
Braz J Biol ; 80(1): 39-46, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31017232

RESUMEN

The current study aimed to assess whether the A122V causal polymorphism promotes alterations in the functional and structural proprieties of the CXC chemokine receptor type 1 protein (CXCR1) of cattle Bos taurus by in silico analyses. Two amino acid sequences of bovine CXCR1 was selected from database UniProtKB/Swiss-Prot: a) non-polymorphic sequence (A7KWG0) with alanine (A) at position 122, and b) polymorphic sequence harboring the A122V polymorphism, substituting alanine by valine (V) at same position. CXCR1 sequences were submitted as input to different Bioinformatics' tools to examine the effects of this polymorphism on functional and structural stabilities, to predict eventual alterations in the 3-D structural modeling, and to estimate the quality and accuracy of the predictive models. The A122V polymorphism exerted tolerable and non-deleterious effects on the polymorphic CXCR1, and the predictive structural model for polymorphic CXCR1 revealed an alpha helix spatial structure typical of a receptor transmembrane polypeptide. Although higher variations in the distances between pairs of amino acid residues at target-positions are detected in the polymorphic CXCR1 protein, more than 97% of the amino acid residues in both models were located in favored and allowed conformational regions in Ramachandran plots. Evidences has supported that the A122V polymorphism in the CXCR1 protein is associated with increased clinical mastitis incidence in dairy cows. Thus, the findings described herein prove that the replacement of the alanine by valine amino acids provokes local conformational changes in the A122V-harboring CXCR1 protein, which could directly affect its post-translational folding mechanisms and biological functionality.


Asunto(s)
Polimorfismo de Nucleótido Simple , Receptores de Interleucina-8A , Secuencia de Aminoácidos , Animales , Bovinos , Femenino
2.
Braz J Biol ; 80(1): 81-86, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31017236

RESUMEN

Wilson's Plover, Charadrius wilsonia, is widely distributed in coastal areas of the Americas. This report presents the first record of breeding in this species on Coroa do Avião Island, on the coast of Pernambuco, and in the estuary of the Cardoso and Camurupim rivers, on the coast of Piauí, in northeastern Brazil, extending the known area of reproduction of this species in this region. One breeding pair was observed on October 29th 2014 on Coroa do Avião Island, and a second pair was recorded on April 6th 2016 in the Cardoso/Camurupim estuary on the Piauí coast. Both the male and the female contributed to the incubation of the eggs. The nest on Coroa do Avião island was camouflaged by the local vegetation, but despite this, the eggs were attacked by a predator. Possible predators observed on the island included Caracara plancus and domestic cats and dogs.


Asunto(s)
Cruzamiento , Charadriiformes , Animales , Brasil , Gatos , Perros , Femenino , Masculino , Reproducción
3.
Braz. j. biol ; 80(1): 81-86, Feb. 2020. graf
Artículo en Inglés | LILACS | ID: biblio-1089303

RESUMEN

Abstract Wilson's Plover, Charadrius wilsonia, is widely distributed in coastal areas of the Americas. This report presents the first record of breeding in this species on Coroa do Avião Island, on the coast of Pernambuco, and in the estuary of the Cardoso and Camurupim rivers, on the coast of Piauí, in northeastern Brazil, extending the known area of reproduction of this species in this region. One breeding pair was observed on October 29th 2014 on Coroa do Avião Island, and a second pair was recorded on April 6th 2016 in the Cardoso/Camurupim estuary on the Piauí coast. Both the male and the female contributed to the incubation of the eggs. The nest on Coroa do Avião island was camouflaged by the local vegetation, but despite this, the eggs were attacked by a predator. Possible predators observed on the island included Caracara plancus and domestic cats and dogs.


Resumo Charadrius wilsonia (Wilson's Plover) está amplamente distribuído pela costa das Américas. Este é o primeiro registro de reprodução no litoral de Pernambuco, Coroa do Avião, e no estuário dos rios Cardoso e Camurupim, litoral do Piauí, Brasil, ampliando a área de reprodução no Nordeste do Brasil. Foi encontrado um casal em período reprodutivo em 23 de outubro de 2014 na ilha Coroa do Avião, litoral de Pernambuco e outro registro em 06 de abril de 2016 nos estuários Cardoso e Camurupim, litoral do Piauí. Foi observado que o macho e a fêmea contribuem na incubação dos ovos. A vegetação na ilha contribui para a camuflagem do ninho, bem como na proteção dos ovos pelos predadores. Apesar da proteção ocorreu a predação do ninho na ilha Coroa do Avião. Alguns possíveis predadores foram registrados na ilha, como Caracara plancus que diariamente frequentam a área e animais domésticos como cães e gatos.


Asunto(s)
Animales , Masculino , Femenino , Gatos , Perros , Cruzamiento , Charadriiformes , Reproducción , Brasil
4.
Braz. j. biol ; 80(1): 39-46, Feb. 2020. graf
Artículo en Inglés | LILACS | ID: biblio-1089293

RESUMEN

Abstract The current study aimed to assess whether the A122V causal polymorphism promotes alterations in the functional and structural proprieties of the CXC chemokine receptor type 1 protein (CXCR1) of cattle Bos taurus by in silico analyses. Two amino acid sequences of bovine CXCR1 was selected from database UniProtKB/Swiss-Prot: a) non-polymorphic sequence (A7KWG0) with alanine (A) at position 122, and b) polymorphic sequence harboring the A122V polymorphism, substituting alanine by valine (V) at same position. CXCR1 sequences were submitted as input to different Bioinformatics' tools to examine the effects of this polymorphism on functional and structural stabilities, to predict eventual alterations in the 3-D structural modeling, and to estimate the quality and accuracy of the predictive models. The A122V polymorphism exerted tolerable and non-deleterious effects on the polymorphic CXCR1, and the predictive structural model for polymorphic CXCR1 revealed an alpha helix spatial structure typical of a receptor transmembrane polypeptide. Although higher variations in the distances between pairs of amino acid residues at target-positions are detected in the polymorphic CXCR1 protein, more than 97% of the amino acid residues in both models were located in favored and allowed conformational regions in Ramachandran plots. Evidences has supported that the A122V polymorphism in the CXCR1 protein is associated with increased clinical mastitis incidence in dairy cows. Thus, the findings described herein prove that the replacement of the alanine by valine amino acids provokes local conformational changes in the A122V-harboring CXCR1 protein, which could directly affect its post-translational folding mechanisms and biological functionality.


Resumo O presente estudo objetivou avaliar se o polimorfismo causal A122V promove alterações nas propriedades funcionais e estruturais da proteína receptora de quimiocina CXC do tipo 1 (CXCR1) de bovino Bos taurus por análises in silico. Duas sequências de aminoácidos da CXCR1 bovina foram selecionadas a partir do banco de dados UniProtKB/Swiss-Prot: a) sequência não-polimórfica (A7KWG0) contendo alanina (A) na posição 122, e b) sequência polimórfica carreando o polimorfismo A122V, causando a substituição de alanina por valina (V) na mesma posição. As sequências CXCR1 foram analisadas por diferentes ferramentas de Bioinformática para examinar o efeito desse polimorfismo sobre sua estabilidade, função e estrutura, predizer eventuais alterações na sua modelagem estrutural 3-D, bem como estimar a qualidade dos modelos preditos. O polimorfismo A122V exerceu efeitos toleráveis e não-deletérios sobre a CXCR1 polimórfica, apresentando um modelo estrutural de alfa-hélice típico de uma proteína receptora transmembranar para ambas as proteínas. Embora maiores variações nas distâncias entre os pares de aminoácidos nas posições-alvo tenham sido detectadas na proteína polimórfica, mais do que 97% dos aminoácidos em ambos os modelos foram situados em regiões ditas favoráveis e permitidas nos diagramas de Ramachandran. Evidências sustentam que o polimorfismo de nucleotídeo único A122V na proteína receptora CXCR1 está associado à aumentada incidência de mastite clínica em vacas leiteiras. Assim, as descobertas descritas aqui comprovam que a substituição do aminoácido alanina por valina provoca mudanças conformacionais locais na proteína CXCR1 polimórfica, que podem estar diretamente afetando seus mecanismos de enovelamento pós-traducionais e sua função biológica.


Asunto(s)
Animales , Femenino , Polimorfismo de Nucleótido Simple , Receptores de Interleucina-8A , Bovinos , Secuencia de Aminoácidos
5.
Chemosphere ; 38(12): 2753-65, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10214713

RESUMEN

We used the duplicate portion method to measure the daily dietary intake of total and congener-specific polychlorinated biphenyls (PCB) and to assess their potential toxicity in a group of 20 subjects consuming a typical Italian diet. The mean +/- SD intake of total PCB, measured by GC-MS, was 3.72 +/- 1.51 micrograms/person/day, comparable to values reported in similar studies world-wide, with individual intakes varying within one order of magnitude, from 0.97 to 10.59 micrograms/person/day. The di-ortho congeners 153, 18 and 138 were the PCB found in the highest concentrations (respectively 13.8%, 11.4% and 10.9% of the total) while the non-ortho coplanar congeners (77, 126 and 169) amounted to 0.5% of the total. The corresponding levels of toxicity (TCDD-like TEQ values ascribable to PCB) ranged from 4.6 up to 119 pg/person/day of TCDD-equivalents in 18 subjects, i.e. presumed no-risk levels, but with peaks of 2109 and 4553 pg/person/day in two subjects with significant intakes of the congener 126. Principal components analysis and redundancy analysis showed dairy products, meat and fish were the principal sources of PCB, and vegetables those with the highest toxicity index in the Italian diet.


Asunto(s)
Dieta , Contaminantes Ambientales/análisis , Contaminantes Ambientales/toxicidad , Contaminación de Alimentos , Bifenilos Policlorados/análisis , Bifenilos Policlorados/toxicidad , Adulto , Contaminantes Ambientales/metabolismo , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Italia , Masculino , Persona de Mediana Edad , Análisis Multivariante , Bifenilos Policlorados/metabolismo , Dibenzodioxinas Policloradas/toxicidad
6.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467257

RESUMEN

Abstract The current study aimed to assess whether the A122V causal polymorphism promotes alterations in the functional and structural proprieties of the CXC chemokine receptor type 1 protein (CXCR1) of cattle Bos taurus by in silico analyses. Two amino acid sequences of bovine CXCR1 was selected from database UniProtKB/Swiss-Prot: a) non-polymorphic sequence (A7KWG0) with alanine (A) at position 122, and b) polymorphic sequence harboring the A122V polymorphism, substituting alanine by valine (V) at same position. CXCR1 sequences were submitted as input to different Bioinformatics tools to examine the effects of this polymorphism on functional and structural stabilities, to predict eventual alterations in the 3-D structural modeling, and to estimate the quality and accuracy of the predictive models. The A122V polymorphism exerted tolerable and non-deleterious effects on the polymorphic CXCR1, and the predictive structural model for polymorphic CXCR1 revealed an alpha helix spatial structure typical of a receptor transmembrane polypeptide. Although higher variations in the distances between pairs of amino acid residues at target-positions are detected in the polymorphic CXCR1 protein, more than 97% of the amino acid residues in both models were located in favored and allowed conformational regions in Ramachandran plots. Evidences has supported that the A122V polymorphism in the CXCR1 protein is associated with increased clinical mastitis incidence in dairy cows. Thus, the findings described herein prove that the replacement of the alanine by valine amino acids provokes local conformational changes in the A122V-harboring CXCR1 protein, which could directly affect its post-translational folding mechanisms and biological functionality.


Resumo O presente estudo objetivou avaliar se o polimorfismo causal A122V promove alterações nas propriedades funcionais e estruturais da proteína receptora de quimiocina CXC do tipo 1 (CXCR1) de bovino Bos taurus por análises in silico. Duas sequências de aminoácidos da CXCR1 bovina foram selecionadas a partir do banco de dados UniProtKB/Swiss-Prot: a) sequência não-polimórfica (A7KWG0) contendo alanina (A) na posição 122, e b) sequência polimórfica carreando o polimorfismo A122V, causando a substituição de alanina por valina (V) na mesma posição. As sequências CXCR1 foram analisadas por diferentes ferramentas de Bioinformática para examinar o efeito desse polimorfismo sobre sua estabilidade, função e estrutura, predizer eventuais alterações na sua modelagem estrutural 3-D, bem como estimar a qualidade dos modelos preditos. O polimorfismo A122V exerceu efeitos toleráveis e não-deletérios sobre a CXCR1 polimórfica, apresentando um modelo estrutural de alfa-hélice típico de uma proteína receptora transmembranar para ambas as proteínas. Embora maiores variações nas distâncias entre os pares de aminoácidos nas posições-alvo tenham sido detectadas na proteína polimórfica, mais do que 97% dos aminoácidos em ambos os modelos foram situados em regiões ditas favoráveis e permitidas nos diagramas de Ramachandran. Evidências sustentam que o polimorfismo de nucleotídeo único A122V na proteína receptora CXCR1 está associado à aumentada incidência de mastite clínica em vacas leiteiras. Assim, as descobertas descritas aqui comprovam que a substituição do aminoácido alanina por valina provoca mudanças conformacionais locais na proteína CXCR1 polimórfica, que podem estar diretamente afetando seus mecanismos de enovelamento pós-traducionais e sua função biológica.

7.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467261

RESUMEN

Abstract Wilsons Plover, Charadrius wilsonia, is widely distributed in coastal areas of the Americas. This report presents the first record of breeding in this species on Coroa do Avião Island, on the coast of Pernambuco, and in the estuary of the Cardoso and Camurupim rivers, on the coast of Piauí, in northeastern Brazil, extending the known area of reproduction of this species in this region. One breeding pair was observed on October 29th 2014 on Coroa do Avião Island, and a second pair was recorded on April 6th 2016 in the Cardoso/Camurupim estuary on the Piauí coast. Both the male and the female contributed to the incubation of the eggs. The nest on Coroa do Avião island was camouflaged by the local vegetation, but despite this, the eggs were attacked by a predator. Possible predators observed on the island included Caracara plancus and domestic cats and dogs.


Resumo Charadrius wilsonia (Wilsons Plover) está amplamente distribuído pela costa das Américas. Este é o primeiro registro de reprodução no litoral de Pernambuco, Coroa do Avião, e no estuário dos rios Cardoso e Camurupim, litoral do Piauí, Brasil, ampliando a área de reprodução no Nordeste do Brasil. Foi encontrado um casal em período reprodutivo em 23 de outubro de 2014 na ilha Coroa do Avião, litoral de Pernambuco e outro registro em 06 de abril de 2016 nos estuários Cardoso e Camurupim, litoral do Piauí. Foi observado que o macho e a fêmea contribuem na incubação dos ovos. A vegetação na ilha contribui para a camuflagem do ninho, bem como na proteção dos ovos pelos predadores. Apesar da proteção ocorreu a predação do ninho na ilha Coroa do Avião. Alguns possíveis predadores foram registrados na ilha, como Caracara plancus que diariamente frequentam a área e animais domésticos como cães e gatos.

8.
Am J Phys Med ; 65(5): 223-44, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3766709

RESUMEN

A piecewise linear model of the elbow antagonistic muscle pair under isometric conditions was developed. The model consists of a linear myoelectric signal-joint force relationship with a mild slope for the force range of 0-30%, and a second, linear segment of steeper slope for the range of 30%-100%. The slope of the agonist, whether biceps or triceps, is fixed for most of the force range at about 1.16 regardless of elbow angle, whereas the slope of the antagonist varies with elbow angle. The antagonist muscle varies its response in such a way that it regulates the net torque about the joint, compensating for the effect of the gravity vector on the joint geometry and limb mass to stabilize the joint. The myoelectric profile of the medial gastrocnemius muscle of the cat during recruitment at synchronous firing rate of 51 pps (maximal tetanic rate) was obtained and compared with the above model. The force-EMG relationship for recruitment was fitted with a second-order polynomial similar but not equivalent to that of the EMG-joint force model. The minor differences were attributed to the effect of the antagonist, proprioception, ligament status and joint geometry.


Asunto(s)
Articulación del Codo/fisiología , Gravitación , Músculos/fisiología , Conducción Nerviosa , Reclutamiento Neurofisiológico , Animales , Fenómenos Biomecánicos , Gatos , Electromiografía , Humanos , Modelos Biológicos
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