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2.
Europace ; 25(12)2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38019960

RESUMO

AIMS: The compatibility of cardiac pacing with the presence of a subcutaneous implantable cardioverter-defibrillator (S-ICD) has been investigated, but S-ICD screening test results have not been compared among different pacing sites. The objective was to compare S-ICD screening results among different cardiac pacing sites and to assess the electrocardiographic predictors of success. METHODS AND RESULTS: This prospective single-centre study conducted automated S-ICD screening in 102 carriers of cardiac pacing devices in conduction system (CSP), biventricular (BVP), right ventricular outflow tract (RVOT), or right ventricular apex (RVA) pacing sites. The study included 102 patients: 40 with CSP (20 left bundle pacing and 20 His bundle pacing), 21 with BVP, and 20 and 21 with RVOT and RVA pacing, respectively. The percentage of positive screenings was significantly higher for CSP (97.5%) than for the other patient groups (BVP 71.4%, RVOT 70%, and RVA 19%). In multivariate analysis, positive screening was associated with a narrower QRS (OR 0.95 [0.92-0.98] P = 0.001) and higher R/T ratio in precordial leads (1.76 [1.18-2.61]). CONCLUSION: A higher S-ICD eligibility rate of cardiac pacing device carriers was obtained in CSP than in conventional pacing (RVA or RVOT) or BVP. The presence of narrower paced QRS width and paced corrected QT interval and of higher R/T ratio in precordial and limb leads are electrocardiographic predictors of a positive response to screening.


Assuntos
Terapia de Ressincronização Cardíaca , Desfibriladores Implantáveis , Marca-Passo Artificial , Humanos , Estudos Prospectivos , Estimulação Cardíaca Artificial/métodos , Cardioversão Elétrica/métodos , Eletrocardiografia , Resultado do Tratamento
3.
Int J Sports Med ; 41(8): 545-551, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32289841

RESUMO

The aim of this study was to determine the influence of body weight or lean body mass-based load on Wingate Anaerobic Test performance in male and female endurance trained individuals. Thirty-one participants (22 male cyclists and triathletes and 9 female triathletes) completed two randomized Wingate Anaerobic Test (body weight and lean body mass loads) in stationary start. There were no significant differences in power outputs variables between loads in any group. However, when comparing specific groups within the sample (e. g. cyclists vs cyclists) medium to large effect sizes were observed for Relative Mean Power Output (ES=0.53), Relative Lowest Power (ES=0.99) and Relative Power Muscle Mass (ES=0.54). Regarding gender differences, male cyclists and triathletes displayed higher relative and absolute power outputs (p<0.001) compared to female triathletes regardless of the protocol used. FI was lower in female triathletes compared to male triathletes and cyclists in body weight (p<0.001) and lean body mass (p<0.01) protocols. Body composition and anthropometric characteristics were similar in male cyclists and triathletes, but there were differences between genders. These results suggest that using either body weight-based or lean body mass-based load can be used interchangeably. However, there may be some practically relevant differences when evaluating this on an individual level.


Assuntos
Índice de Massa Corporal , Peso Corporal , Resistência Física/fisiologia , Esportes/fisiologia , Adulto , Ciclismo/fisiologia , Estudos Cross-Over , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Corrida/fisiologia , Fatores Sexuais , Natação/fisiologia , Adulto Jovem
4.
Trop Anim Health Prod ; 52(5): 2737-2741, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32198611

RESUMO

The effect of concentrate supplementation to crossbred goats on rangeland during the dry period on their reproductive performance was investigated. Goats were assigned into two groups: a concentrate supplemented (S; n = 91) group and an unsupplemented (UNS; n = 118) group. S goats received 350 g/day of concentrate per head, 30 days prior to breeding (flushing in winter) and 30 days during the last trimester of pregnancy. UNS goats presented a lower (P < 0.01) liveweight at the onset of the breeding period than did the S group (38.2 ± 3.7 vs. 44.4 ± 3.6 kg). Average daily gains during pregnancy were higher (P < 0.01) in the S group than UNS goats (15.5 ± 1.2 vs. - 0.5 ± 5.1 g/d). S goats had a higher (P < 0.01) kidding rate (87.1%) than the UNS goats (54.7%). Litter size for UNS and S goats was 1.39 and 2.00, respectively (P < 0.01). Serum triiodothyronine, tetraiodothyronine, and cortisol concentration at the end of the flushing period were not affected by concentrate supplementation. Serum glucose (88.7 ± 3.8 vs. 95.7 ± 5.3 mg/dL), total protein (6.9 ± 1.1 vs. 8.2 ± 1.2 mg/dL), and blood urea nitrogen (17.1 vs. 21.0 ± 4.3 mg/dL) concentrations were lower for UNS goats as compared with S goats. In conclusion, concentrate supplementation in crossbred goats on rangeland markedly improved body mass changes during gestation and the reproductive performance, which implies that malnutrition is a major barrier affecting fertility of goats and liveweight of kids in this rangeland.


Assuntos
Suplementos Nutricionais , Cabras/fisiologia , Reprodução , Fenômenos Fisiológicos da Nutrição Animal , Animais , Cruzamento , Feminino , Hidrocortisona/sangue , Tamanho da Ninhada de Vivíparos , Gravidez , Distribuição Aleatória , Hormônios Tireóideos/sangue
5.
Faraday Discuss ; 217(0): 98-113, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31016298

RESUMO

The combination of cryogenic ion traps with suitable light sources and standard tools of mass spectrometry has led to many innovative applications in previous years. This paper presents the combination of our versatile instrument with a supercontinuum laser for the rapid identification of ions that might be of special interest, e.g. as candidates for diffuse interstellar bands carriers. Using a linear wire quadrupole ion trap at 3 K, routine He-tagging, long irradiation times, and the brilliance and wide spectral range of a crystal fiber laser, mass selected ions have been exposed to spectral fluencies larger than 10 mJ (nm cm2)-1. These conditions result in an unsurpassed sensitivity, allowing us to find out within a few minutes and with nm accuracy, where photo absorption occurs with cross sections above 10-18 cm2. In this contribution, we present a variety of ions, probed between 420 and 720 nm. They have been generated by electron- or electrospray ionization of (polycyclic) aromatic hydrocarbons. For selected candidates, we recorded spectra with higher resolution and in the IR range. The anthracene dication has been selected to present a detailed analysis of our new results.

6.
Rev. colomb. cienc. pecu ; 29(4): 288-295, oct.-dic. 2016. tab
Artigo em Inglês | LILACS | ID: biblio-1042778

RESUMO

Summary Background: Katahdin breed sheep is highly disseminated in Mexico. This breed and its crosses have recently gained attention among sheep producers. However, research with crosses between Katahdin and other meat breeds is limited. Objective: to evaluate the genetic and non-genetic factors affecting growth and mortality rate of crossbred lambs from Katahdin ewes fecundated with breeds specialized for meat production. Methods: crossbred lambs (n = 152) from Katahdin ewes sired with Hampshire (KH; n = 43), Texel (KT; n = 53) or Charolais (KCH; n = 56) were evaluated under intensive management conditions. The effects of genotype and non-genetic factors on birth weight, weaning weight, pre-weaning daily weight gain, and mortality rate were determined. Results: breed differences were not detected for birth weight (4 ± 1.1, 4.3 ± 0.9 and 4 ± 1.1 Kg for KCH, KH, KT, respectively), nor for the 60-d weaning weight (20.2 ± 4.3, 20.9 ± 4.3, 18.2 ± 4.2 Kg for KCH, KH, KT, respectively). Weight of lambs did not differ significantly between sexes, but it decreased (p<0.05) with increased litter size (weaning weight at 60 days for single, twins and triplets was 24.5 ± 2.6, 19.2 ± 3.5, and 14.3 ± 3.8 Kg, respectively). Pre-weaning mortality of KH lambs was 13.3% and it was significantly lower than that of the other genotypes (24.5 and 39.3% for KT and KCH, respectively). Conclusion: inclusion of Charolais, Hampshire or Texel rams in Katahdin flocks results in similar lamb weaning weight, but Hampshire-sired progeny excels regarding pre-weaning survival.


Resumen Antecedentes: la raza de ovejas Katahdin se ha difundido ampliamente en México. Esta raza y sus cruces han ganado recientemente la atención de los productores de ovinos; sin embargo, la investigación con cruces entre Katahdin y otras razas productoras de carne es limitada. Objetivo: evaluar factores genéticos y no genéticos que afectan las tasas de crecimiento y mortalidad de corderos hijos de ovejas Katahdin fecundadas con razas de carne. Métodos: corderos híbridos (n = 152) derivados de ovejas Katahdin fecundadas con machos Hampshire (KH; n = 43), Texel (KT; n = 53) y Charolais (KCH; n = 56) se evaluaron bajo condiciones intensivas de manejo. Se determinó el efecto del genotipo y factores no genéticos en el peso al nacer, peso al destete, ganancia de peso pre-destete, tasa de ganancia de peso pos-destete y mortalidad de los corderos. Resultados: no se detectaron diferencias entre grupos raciales para el peso al nacer (4 ± 1,1, 4,3 ± 0,9 y 4 ± 1,1 Kg para KCH, KH, KT, respectivamente) ni para el peso al destete realizado a los 60 días (20,2 ± 4,3, 20,9 ± 4,3, 18,2 ± 4,2 Kg para KCH, KH, KT, respectivamente). Los pesos de los corderos no difirieron significativamente entre sexos, pero disminuyeron (p<0,05) con el aumento del tamaño de la camada (el peso al destete a los 60 días para los corderos individuales, gemelos y trillizos fue 24,5 ± 2,6, 19,2 ± 3,5 y 14,3 ± 3,8 Kg, respectivamente). La tasa de mortalidad pre-destete de los corderos KH fue de 13,3% y fue significativamente más baja que la de los otros genotipos (24,5 y 39,3% para KT y KCH, respectivamente). Conclusión: el uso de sementales Charolais, Hampshire o Texel en rebaños de ovejas Katahdin genera resultados similares para peso de los corderos a los 60 días, pero la progenie de los moruecos Hampshire tiene mayor sobrevivencia hasta el destete.


Resumo Antecedentes: Katahdin é uma raça de ovelhas altamente disseminada no México. Esta raça e seus cruzamentos têm recentemente ganhado atenção entre os produtores de ovinos. No entanto, a pesquisa com cordeiros híbridos entre Katahdin e outras raças de carne é ainda limitada. Objetivo: avaliar os fatores genéticos e não-genéticos que afetam a taxa de crescimento e a taxa de mortalidade de cordeiros híbridos de ovelhas Katahdin fecundadas com raças de carne. Métodos: cordeiros cruzados (n= 152) derivados de ovelhas Katahdin fecundados com carneiro Hampshire (KH; n = 43), Texel (KT; n = 53) e Charolais (KCH; n = 56) foram usadas neste estudo sob condições intensivas. Foi determinado o efeito do genótipo e dos fatores nãogenéticos sobre o peso ao nascimento, peso ao desmame, peso pré-desmame e percentagem de sobrevivência. Resultados: não foram detectadas diferenças raciais por peso ao nascimento (4 ± 1,1, 4,3 ± 0,9 e 4 ± 1,1 Kg para KCH, KH, KT, respectivamente), e peso ao desmame aos 60 dias (20,2 ± 4,3, 20,9 ± 4,3, 18,2 ± 4,2 Kg para KCH, KH, KT, respectivamente). Os pesos dos cordeiros não diferiram significativamente entre os sexos, mas o peso diminuiu (p<0,05) com o aumento do tamanho da leitegada (o peso ao desmame aos 60 dias de cordeiros individuais, gêmeos e trigêmeos foi de 24,5 ± 2,6, 19,2 ± 3,5 e 14,3 ± 3,8 Kg, respectivamente). A taxa de mortalidade pré-desmame dos cordeiros KH foi de 13.3% e este foi significativamente menor do que a taxa de mortalidade de cordeiros dos demais genótipos ( 24,5 e 39,3% para KT e KCH, respectivamente). Conclusão: o uso de carneiros Hampshire, Charolês ou carneiros Texel em ovelhas Katahdin pode ser implementado com resultados semelhantes para o peso do cordeiro ao desmame, mas a descendência Hampshire destacou-se por sua maior sobrevivência até o desmame.

7.
PLoS One ; 9(1): e83779, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24416172

RESUMO

Burkholderia is a diverse and dynamic genus, containing pathogenic species as well as species that form complex interactions with plants. Pathogenic strains, such as B. pseudomallei and B. mallei, can cause serious disease in mammals, while other Burkholderia strains are opportunistic pathogens, infecting humans or animals with a compromised immune system. Although some of the opportunistic Burkholderia pathogens are known to promote plant growth and even fix nitrogen, the risk of infection to infants, the elderly, and people who are immunocompromised has not only resulted in a restriction on their use, but has also limited the application of non-pathogenic, symbiotic species, several of which nodulate legume roots or have positive effects on plant growth. However, recent phylogenetic analyses have demonstrated that Burkholderia species separate into distinct lineages, suggesting the possibility for safe use of certain symbiotic species in agricultural contexts. A number of environmental strains that promote plant growth or degrade xenobiotics are also included in the symbiotic lineage. Many of these species have the potential to enhance agriculture in areas where fertilizers are not readily available and may serve in the future as inocula for crops growing in soils impacted by climate change. Here we address the pathogenic potential of several of the symbiotic Burkholderia strains using bioinformatics and functional tests. A series of infection experiments using Caenorhabditis elegans and HeLa cells, as well as genomic characterization of pathogenic loci, show that the risk of opportunistic infection by symbiotic strains such as B. tuberum is extremely low.


Assuntos
Infecções por Burkholderia/microbiologia , Burkholderia/fisiologia , Mamíferos/microbiologia , Plantas/microbiologia , Simbiose , Animais , Sistemas de Secreção Bacterianos/genética , Burkholderia/genética , Burkholderia/patogenicidade , Caenorhabditis elegans/microbiologia , Resistência Microbiana a Medicamentos/genética , Flagelos/genética , Genes Bacterianos/genética , Loci Gênicos , Células HeLa , Humanos , Família Multigênica , Filogenia , Simbiose/genética , Virulência/genética
8.
Antonie Van Leeuwenhoek ; 104(6): 1063-71, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24057982

RESUMO

During a survey of Burkholderia species with potential use in agrobiotechnology, a group of 12 strains was isolated from the rhizosphere and rhizoplane of tomato plants growing in Mexico (Nepantla, Mexico State). A phylogenetic analysis of 16S rRNA gene sequences showed that the strains are related to Burkholderia kururiensis and Burkholderia mimosarum (97.4 and 97.1 %, respectively). However, they induced effective nitrogen-fixing nodules on roots of Phaseolus vulgaris. Based on polyphasic taxonomy, the group of strains represents a novel species for which the name Burkholderia caballeronis sp. nov. is proposed. The type species is TNe-841(T) (= LMG 26416(T) = CIP 110324(T)).


Assuntos
Burkholderia/classificação , Burkholderia/fisiologia , Fixação de Nitrogênio , Phaseolus/microbiologia , Nodulação , Solanum lycopersicum/microbiologia , Técnicas de Tipagem Bacteriana , Burkholderia/genética , Burkholderia/isolamento & purificação , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , México , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
9.
Rev. colomb. cienc. pecu ; 26(3): 193-200, jul.-set. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-691194

RESUMO

Background: high environmental temperature coupled with high humidity can result in reproductive failure in dairy cattle, with a drastic reduction in reproductive efficiency of dairy herds. Objective: to study the effect of high environmental temperature on reproduction performance of Holstein cows treated with recombinant bovine somatotropin (rbST) throughout lactation in an arid environment. Methods: reproductive variables (n=18,037 services) from a large dairy herd were evaluated with respect to the maximum temperaturehumidity index (THI) prior to breeding, on the breeding day, and after breeding. The GENMOD procedure of SAS was used to assess the effect of THI and month of breeding on pregnancy by artificial insemination (P/AI). Results: increased THI from ≤ 70 to ≥ 95 units was associated with a decrease in P/AI from 47% to 26%. P/AI for cows inseminated on extremely hot days (THI= 85 to 90) preceded by cooler temperatures was six percent points higher than cows subjected to high temperatures before breeding. P/AI was higher (p<0.05) from January to March (39% to 41%) compared with the rest of the year (27% to 35%). The average number of inseminations per pregnancy was higher (p<0.05) from May to July (3.0 to 3.4) compared to other months (2.1 to 3.0). Conclusions: in this particular hot-arid environment (maximum temperature >38 ºC most of the year, and 230 mm mean annual rainfall), heat stress shortly before or after breeding severely compromises the breeding success of high yielding Holstein cows.


Antecedentes: la asociación entre temperaturas ambientales elevadas y alta humedad conduce a fallas reproductivas, disminuyendo la fertilidad de hatos lecheros. Objetivo: determinar el efecto de temperaturas ambientales elevadas sobre el comportamiento reproductivo de vacas Holstein mantenidas en un ambiente árido y cálido y tratadas con hormona del crecimiento (rbST) durante toda la lactancia. Métodos: las variables reproductivas (n=18037 servicios) de una explotación comercial fueron evaluadas con respecto al máximo índice temperatura humedad (THI) antes, durante y después de la inseminación de las vacas. El procedimiento GENMOD de SAS se utilizó para determinar el efecto del THI y el mes de inseminación sobre las tasas de preñez (P/AI). Resultados: el incremento del THI de ≤ 70 a ≥ 95 unidades se asoció con una disminución en el P/AI de 47% a 26%. El P/AI para las vacas inseminadas en días con un ITH de 85 a 90, pero con temperaturas menos cálidas antes de la inseminación, fue de seis puntos porcentuales más altos (30% vs. 36%) que en las vacas expuestas a ITH más altos antes de la inseminación. El P/AI fue mayor (p<0,05) de enero a marzo (39% a 41%) comparado con el resto de los meses del año (27-35%). El número de servicios por preñez fue mayor (p<0,05) de mayo a julio (3,0 a 3,4) que en los otros meses del año (2,1 a 3,0). Conclusiones: en este ambiente extremadamente caliente (temperaturas máximas > 38 °C la mayor parte del año) y árido (promedio de precipitación anual de 230 mm), el estrés calórico poco antes o después de la inseminación disminuye drásticamente las probabilidades de establecer una gestación en vacas de alta producción de leche.


Antecedentes: a associação entre alta temperatura e umidade no ambiente pode originar problemas reprodutivos, diminuindo o índice de fertilidade dos rebanhos leiteiros. Objetivo: avaliar o efeito da elevada temperatura ambiente sobre o desempenho reprodutivo de vacas da raça Holandês mantidas num ambiente quente e árido, as quais foram tratadas com somatotropina bovina recombinante (rBST) durante toda a lactação. Métodos: as variáveis reprodutivas (n = 18037 serviços) de um rebanho leiteiro foram avaliadas em relação ao máximo índice de temperatura-umidade (THI), antes, durante e depois da inseminação artificial das vacas. O procedimento GENMOD do SAS foi usado para avaliar o efeito do THI e do mês de reprodução sobre as taxas de gestação por inseminação artificial (P/AI). Resultados: o aumento do THI de ≤ 70 para ≥ 95 unidades foi associado com a diminuição no índice P/AI, de 47% a 26%. Em dias com THI de 85 - 90, mas com menor temperatura ambiental antes da inseminação, o índice P/AI foi 6% maior do que nas vacas expostas a superior THI. O índice P/AI foi maior (p<0,05) de janeiro a março (39% a 41%), em comparação aos outros meses do ano (27 a 35%). O número médio de inseminações por prenhez foi superior (p<0,05) de maio a julho (3,0 a 3,4) quando comparado aos outros meses do ano (2,1 a 3,0). Conclusões: em ambiente quente e seco (temperaturas máximas > 38°C a maior parte do ano, média de precipitação anual de 230 mm) o estresse térmico antes e depois da inseminação reduz drasticamente a possibilidade de estabelecer uma gestação em vacas de alta produção de leite.

10.
Bioengineered ; 4(4): 236-43, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23680857

RESUMO

It has been documented that bacteria from the Burkholderia genera produce different kinds of compounds that inhibit plant pathogens, however in Burkholderia tropica, an endophytic diazotrophic and phosphate-solubilizing bacterium isolated from a wide diversity of plants, the capacity to produce antifungal compounds has not been evaluated. In order to expand our knowledge about Burkholderia tropica as a potential biological control agent, we analyzed 15 different strains of this bacterium to evaluate their capacities to inhibit the growth of four phytopathogenic fungi, Colletotrichum gloeosporioides, Fusarium culmorum, Fusarium oxysporum and Sclerotium rolffsi. Diverse analytical techniques, including plant root protection and dish plate growth assays and gas chromatography-mass spectroscopy showed that the fungal growth inhibition was intimately associated with the volatile compounds produced by B. tropica and, in particular, two bacterial strains (MTo293 and TTe203) exhibited the highest radial mycelial growth inhibition. Morphological changes associated with these compounds, such as disruption of fungal hyphae, were identified by using photomicrographic analysis. By using gas chromatography-mass spectroscopy technique, 18 volatile compounds involved in the growth inhibition mechanism were identified, including α-pinene and limonene. In addition, we found a high proportion of bacterial strains that produced siderophores during growth with different carbon sources, such as alanine and glutamic acid; however, their roles in the antagonism mechanism remain unclear.


Assuntos
Burkholderia/química , Fungos/efeitos dos fármacos , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/farmacologia , Agentes de Controle Biológico , Colletotrichum/efeitos dos fármacos , Fusarium/efeitos dos fármacos
11.
Curr Microbiol ; 67(1): 51-60, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23404651

RESUMO

Burkholderia comprises more than 60 species of environmental, clinical, and agro-biotechnological relevance. Previous phylogenetic analyses of 16S rRNA, recA, gyrB, rpoB, and acdS gene sequences as well as genome sequence comparisons of different Burkholderia species have revealed two major species clusters. In this study, we undertook a multilocus sequence analysis of 77 type and reference strains of Burkholderia using atpD, gltB, lepA, and recA genes in combination with the 16S rRNA gene sequence and employed maximum likelihood and neighbor-joining criteria to test this further. The phylogenetic analysis revealed, with high supporting values, distinct lineages within the genus Burkholderia. The two large groups were named A and B, whereas the B. rhizoxinica/B. endofungorum, and B. andropogonis groups consisted of two and one species, respectively. The group A encompasses several plant-associated and saprophytic bacterial species. The group B comprises the B. cepacia complex (opportunistic human pathogens), the B. pseudomallei subgroup, which includes both human and animal pathogens, and an assemblage of plant pathogenic species. The distinct lineages present in Burkholderia suggest that each group might represent a different genus. However, it will be necessary to analyze the full set of Burkholderia species and explore whether enough phenotypic features exist among the different clusters to propose that these groups should be considered separate genera.


Assuntos
Burkholderia/classificação , Burkholderia/genética , DNA Bacteriano/genética , Variação Genética , Tipagem de Sequências Multilocus/métodos , Filogenia , Animais , Análise por Conglomerados , Genes Bacterianos , Genótipo , Humanos
12.
Appl Microbiol Biotechnol ; 97(10): 4639-49, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22805783

RESUMO

Azospirillum are prominent plant growth-promoting rhizobacteria (PGPR) extensively used as phytostimulatory crop inoculants, but only few studies are dealing with Azospirillum-containing mixed inocula involving more than two microorganisms. We compared here three prominent Azospirillum strains as part of three-component consortia including also the PGPR Pseudomonas fluorescens F113 and a mycorrhizal inoculant mix composed of three Glomus strains. Inoculant colonization of maize was assessed by quantitative PCR, transcription of auxin synthesis gene ipdC (involved in phytostimulation) in Azospirillum by RT-PCR, and effects on maize by secondary metabolic profiling and shoot biomass measurements. Results showed that phytostimulation by all the three-component consortia was comparable, despite contrasted survival of the Azospirillum strains and different secondary metabolic responses of maize to inoculation. Unexpectedly, the presence of Azospirillum in the inoculum resulted in lower phytostimulation in comparison with the Pseudomonas-Glomus two-component consortium, but this effect was transient. Azospirillum's ipdC gene was transcribed in all treatments, especially with three-component consortia, but not with all plants and samplings. Inoculation had no negative impact on the prevalence of mycorrhizal taxa in roots. In conclusion, this study brought new insights in the functioning of microbial consortia and showed that Azospirillum-Pseudomonas-Glomus three-component inoculants may be useful in environmental biotechnology for maize growth promotion.


Assuntos
Azospirillum/fisiologia , Glomeromycota/fisiologia , Pseudomonas/fisiologia , Zea mays/crescimento & desenvolvimento , Azospirillum/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Zea mays/microbiologia
13.
Int J Syst Evol Microbiol ; 63(Pt 1): 208-211, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22389284

RESUMO

Phylogenetic analysis of the 16S rRNA gene sequences of strains TE26(T) and K6 belonging to Wautersia numazuensis Kageyama et al. 2005 showed the strains to be deeply intermingled among the species of the genus Cupriavidus. The comparison showed that strain TE26(T) was closely related to the type strains of Cupriavidus pinatubonensis (99.1 % 16S rRNA gene sequence similarity), C. basilensis (98.7 %), C. necator (98.7 %) and C. gilardii (98.0 %). However, DNA-DNA hybridization experiments (less than 20 % relatedness) demonstrated that strain TE26(T) is different from these Cupriavidus species. A comparative phenotypic and chemotaxonomic analysis (based on fatty acid profiles) in combination with the 16S rRNA gene sequence phylogenetic analysis and the DNA-DNA hybridization results supported the incorporation of Wautersia numazuensis into the genus Cupriavidus as Cupriavidus numazuensis comb. nov.; the type strain is TE26(T) (=LMG 26411(T) =DSM 15562(T) = CIP 108892(T)).


Assuntos
Cupriavidus/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Cupriavidus/genética , DNA Bacteriano/genética , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
14.
Syst Appl Microbiol ; 35(5): 310-4, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22738764

RESUMO

A group of 20 bacterial strains was isolated from the rhizosphere of different agricultural plants growing in alkaline soils in the northeast of Mexico. The phylogenetic analysis of the 16S rRNA gene sequence from four strains showed that this novel group belonged to the Cupriavidus genus, with C. taiwanensis (∼98.9%) and C. necator (∼98.8%) as the closest species. However, DNA-DNA reassociation values were less than 20%. The novel group did not fix nitrogen and lacked nifH and nodA genes, unlike C. taiwanensis. Whole-cell protein patterns were highly similar among the 20 strains but different from the closest Cupriavidus species. BOX-PCR patterns were distinct among the 20 strains but also differed from other Cupriavidus type species. The major cellular fatty acids from strains ASC-732(T) and SLV-2362 were C(16:0), C(18:1) ω7c/12t/9t and C(16:1) ω7c and/or C(15:0) iso 2OH. The major polar lipids consisted of phosphatidylglycerol, cardiolipin, phosphatidylethanolamine, 2-hydroxylated-phosphatidylethanolamine and an unknown aminolipid. The DNA G+C content of strain ASC-732(T) was 66.8mol%. All 20 strains grew in the presence of 5-10mgmL(-1) arsenic, 1mgmL(-1) zinc, and 0.1mgmL(-1) copper. Consequently, the group of strains was considered to represent a novel species for which the name Cupriavidus alkaliphilus sp. nov. is proposed. The type strain is ASC-732(T) (=LMG 26294(T)=CIP 110330(T)).


Assuntos
Cupriavidus/classificação , Cupriavidus/isolamento & purificação , Rizosfera , Agricultura , Composição de Bases , Cupriavidus/genética , Concentração de Íons de Hidrogênio , México , Filogenia , Solo/química , Microbiologia do Solo
15.
Microb Ecol ; 63(2): 249-66, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21850446

RESUMO

The genus Burkholderia comprises more than 60 species isolated from a wide range of niches. Although they have been shown to be diverse and ubiquitously distributed, most studies have thus far focused on the pathogenic species due to their clinical importance. However, the increasing number of recently described Burkholderia species associated with plants or with the environment has highlighted the division of the genus into two main clusters, as suggested by phylogenetical analyses. The first cluster includes human, animal, and plant pathogens, such as Burkholderia glumae, Burkholderia pseudomallei, and Burkholderia mallei, as well as the 17 defined species of the Burkholderia cepacia complex, while the other, more recently established cluster comprises more than 30 non-pathogenic species, which in most cases have been found to be associated with plants, and thus might be considered to be potentially beneficial. Several species from the latter group share characteristics that are of use when associating with plants, such as a quorum sensing system, the presence of nitrogen fixation and/or nodulation genes, and the ability to degrade aromatic compounds. This review examines the commonalities in this growing subgroup of Burkholderia species and discusses their prospective biotechnological applications.


Assuntos
Burkholderia/classificação , Burkholderia/fisiologia , Magnoliopsida/microbiologia , Simbiose , Burkholderia/genética , Fungos/fisiologia , Magnoliopsida/fisiologia , Filogenia , Especificidade da Espécie
16.
J Microbiol ; 49(6): 867-76, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22203548

RESUMO

The presence of Burkholderia, Cupriavidus, and Ralstonia species in northeastern Mexico was investigated. An analysis of the root surrounding soil from different agricultural plants led to the isolation of Burkholderia and Cupriavidus species but no Ralstonia strains. Most Cupriavidus species were unknown and grouped into two clusters according to ARDRA profiles. The 16S rRNA sequence analysis showed that the Cupriavidus isolates were highly related among them and with different Cupriavidus species with validated names. However, SDS-PAGE profiles were distinct among the different ARDRA profiles and to other Cupriavidus species examined, suggesting new species in the genus. This shows that Cupriavidus is more widely associated with plants than previously appreciated. The BCC isolate was 99% similar to B. cenocepacia by recA sequence analysis. Additionally, most Cupriavidus strains from the two largest groups grew on media containing up to 0.1 mg/ml of copper, 10.0 mg/ml arsenic and 1.0 mg/ml zinc. Burkholderia strains grew on media containing up to 10.0 mg/ml zinc, 5.0 mg/ml arsenic and 0.1 mg/ml copper.


Assuntos
Burkholderia/isolamento & purificação , Produtos Agrícolas/microbiologia , Cupriavidus/isolamento & purificação , Microbiologia do Solo , Solo/análise , Burkholderia/classificação , Burkholderia/genética , Produtos Agrícolas/crescimento & desenvolvimento , Cupriavidus/classificação , Cupriavidus/genética , DNA Bacteriano/genética , México , Dados de Sequência Molecular , Filogenia , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética
17.
BMC Microbiol ; 11: 228, 2011 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-21995705

RESUMO

BACKGROUND: A close association between maize roots and Burkholderia cepacia complex (BCC) bacteria has been observed in different locations globally. In this study we investigated by MultiLocus Restriction Typing (MLRT) the genetic diversity and relationships among Burkholderia cenocepacia IIIB and BCC6 populations associated with roots of maize plants cultivated in geographically distant countries (Italy and Mexico), in order to provide new insights into their population structure, evolution and ecology. RESULTS: The 31 B. cenocepacia IIIB and 65 BCC6 isolates gave rise to 29 and 39 different restriction types (RTs), respectively. Two pairs of isolates of B. cenocepacia IIIB and BCC6, recovered from both Italian and Mexican maize rhizospheres, were found to share the same RT. The eBURST (Based Upon Related Sequence Types) analysis of MLRT data grouped all the B. cenocepacia IIIB isolates into four clonal complexes, with the RT-4-complex including the 42% of them, while the majority of the BCC6 isolates (94%) were grouped into the RT-104-complex. These two main clonal complexes included RTs shared by both Italian and Mexican maize rhizospheres and a clear relationship between grouping and maize variety was also found. Grouping established by eBURST correlated well with the assessment using unweighted-pair group method with arithmetic mean (UPGMA). The standardized index of association values obtained in both B. cenocepacia IIIB and BCC6 suggests an epidemic population structure in which occasional clones emerge and spread. CONCLUSIONS: Taken together our data demonstrate a wide dispersal of certain B. cenocepacia IIIB and BCC6 isolates in Mexican and Italian maize rhizospheres. Despite the clear relationship found between the geographic origin of isolates and grouping, identical RTs and closely related isolates were observed in geographically distant regions. Ecological factors and selective pressure may preferably promote some genotypes within each local microbial population, favouring the spread of a single clone above the rest of the recombinant population.


Assuntos
Burkholderia cenocepacia/genética , Rizosfera , Microbiologia do Solo , Zea mays/microbiologia , Alelos , Burkholderia cenocepacia/isolamento & purificação , DNA Bacteriano/genética , Variação Genética , Itália , Desequilíbrio de Ligação , México , Raízes de Plantas/microbiologia , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA
18.
Syst Appl Microbiol ; 34(7): 531-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21592712

RESUMO

The aim of this work is the taxonomic characterization of three biosurfactant-producing bacterial isolates from the Churince system at Cuatro Ciénegas Basin (CCB) in the Mexican State of Coahuila, and the study of the possible role of biosurfactant production in their ecology and evolution. We determined that these isolates belong to a Pseudomonas koreensis lineage endemic to CCB, using standard taxonomical techniques, phylogenetic analysis of three chromosomal loci and phenotypic characterization. This new lineage has the distinct capacity to produce a biosurfactant when compared with previously reported P. koreensis isolates recovered from agricultural soils in Korea. We present evidence suggesting that the biosurfactant secreted by CCB P. koreensis strains is involved in their ability to compete with a CCB Exiguobacterium aurantiacum strain (m5-66) used as a model organism in competition experiments. Furthermore, the ethyl acetate extract of culture supernatant of CCB P. koreensis strains results in growth inhibition not only of E. aurantiacum m5-66, but also of a Bacillus subtilis type strain (ATCC6633). Based on these results we propose that the production of biosurfactant could be of ecological importance and could play a role in the separation of the P. koreensis CCB lineage.


Assuntos
Pseudomonas/classificação , Tensoativos/química , Antibacterianos/química , Antibacterianos/farmacologia , Bacillaceae/efeitos dos fármacos , Bacillaceae/crescimento & desenvolvimento , Proteínas de Bactérias/química , Proteínas de Bactérias/farmacologia , Técnicas de Tipagem Bacteriana , Cromossomos/genética , DNA Girase/genética , DNA Ribossômico/genética , Ecologia , Evolução Molecular , Genes Bacterianos , Loci Gênicos , México , Testes de Sensibilidade Microbiana , Fenótipo , Filogenia , Pseudomonas/química , Pseudomonas/genética , Pseudomonas/crescimento & desenvolvimento , Pseudomonas/isolamento & purificação , Recombinases Rec A/genética , Ribossomos/genética , Tensoativos/farmacologia , Microbiologia da Água
19.
Environ Microbiol Rep ; 3(3): 383-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23761284

RESUMO

Although some sugarcane cultivars may benefit substantially from biological nitrogen fixation (BNF), the responsible bacteria have been not identified yet. Here, we examined the active diazotrophic bacterial community in sugarcane roots from Africa and America by reverse transcription (RT)-PCR using broad-range nifH-specific primers. Denaturing gradient gel electrophoresis (DGGE) profiles obtained from sugarcane showed a low diversity at all sample locations with one phylotype amounting up to 100% of the nifH transcripts. This major phylotype has 93.9-99.6% DNA identity to the partial nifH sequence from a strain affiliated with Rhizobium rosettiformans. In addition, nifH transcripts of this phylotype were also detected in spruce roots sampled in Germany, where they made up 91% of nifH transcripts detected. In contrast, in control soil or shoot samples two distinct nifH transcript sequences distantly related to nifH from Sulfurospirillum multivorans or Bradyrhizobium elkanii, respectively, were predominant. These results suggest that R. rosettiformans is involved in root-associated nitrogen fixation with sugarcane and spruce, plants that do not form root-nodule symbioses.

20.
Enferm. clín. (Ed. impr.) ; 20(4): 255-259, jul.-ago. 2010. tab
Artigo em Espanhol | IBECS | ID: ibc-84886

RESUMO

Se presenta el caso de una recién nacida prematura de 27 semanas de gestación y 420g de peso, que nació como consecuencia de una preeclampsia materna y un crecimiento intrauterino retardado. Durante los 125 días de ingreso se desarrolló y aplicó un plan de cuidados individualizado basado en el modelo de Virginia Henderson, tanto a la niña como a sus padres, utilizando los diagnósticos NANDA, las intervenciones según la clasificación de intervenciones de enfermería y los resultados esperados según la clasificación de resultados de enfermería. Para la valoración inicial utilizamos los patrones funcionales de Marjory Gordon. Gracias al plan aplicado, la recién nacida prematura vio suplidas todas sus necesidades, que fueron modificándose a lo largo del tiempo de ingreso con nuevas necesidades que se unían a las que planteaba de base y que requerían una valoración continua con la consiguiente adaptación del plan de cuidados. Asimismo, la atención que requerían los padres fue variando desde el duelo inicial por la posible pérdida de su hija hasta el aprendizaje de los signos de alarma y cuidados a domicilio que requería su hija. Finalmente, la niña fue dada de alta con 2.900 g y un desarrollo neurológico y psicomotor normales, aunque por debajo del peso adecuado a su edad. Asimismo, el vínculo entre los padres y la niña es adecuado. Actualmente, con 2 años de vida, la niña tiene un desarrollo neurológico y psicomotor normal, aunque con percentil en peso y talla inferior al percentil 3. Precisa de tratamiento con logopeda y foniatra por parálisis de la cuerda vocal derecha (AU)


A case is presented of a premature newborn of 27 weeks gestation and weighing 420 grams who was delivered as a result of a maternal pre-eclampsia and retarded intra-uterine growth. During the 125 days of hospitalisation, an individual care plan based on the Virginia Henderson model was devised and applied to both the child and her parents using NANDA diagnostics, interventions according to the NIC classification, and the expected results according to the NOC classification. The Marjory Gordon functional patterns were used for the initial assessment. By applying the pre-term newborn (PTNB) plan, all their needs were provided and were modified throughout the hospital stay, with new needs that were added to the established ones. These required a continuous assessment with the subsequent adapting of the care plan. Likewise, the care required by the parents varied from the initial grief due to the possible loss of their child to learning the alarm signs and the home care that their child would need. The child was finally discharged weighing 2900 grams and with normal neurological and psychomotor development, although with a lower weight appropriate to her age. Currently, at 2 years old, the child has a normal neurological and psychomotor development, but with weight and size lower than the P3 percentile. She requires speech therapy treatment due to paralysis of the right vocal cord (AU)


Assuntos
Humanos , Feminino , Recém-Nascido , Recém-Nascido Prematuro , Enfermagem Neonatal , Diagnóstico de Enfermagem
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