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1.
Curr Microbiol ; 81(6): 144, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38630311

RESUMEN

A group of Gram-negative plant-associated diazotrophic bacteria belonging to the genus Nitrospirillum was investigated, including both previously characterized and newly isolated strains from diverse regions and biomes, predominantly in Brazil. Phylogenetic analysis of 16S rRNA and recA genes revealed the formation of a distinct clade consisting of thirteen strains, separate from the formally recognized species N. amazonense (the closest species) and N. iridis. Comprehensive taxonomic analyses using the whole genomes of four strains (BR 11140T = AM 18T = Y-2T = DSM 2788T = ATCC 35120T, BR 11142T = AM 14T = Y-1T = DSM 2787T = ATCC 35119T, BR 11145 = CBAmC, and BR 12005) supported the division of these strains into two species: N. amazonense (BR 11142 T and BR 12005) and a newly proposed species (BR 11140 T and BR 11145), distinct from N. iridis. The phylogenomic analysis further confirmed the presence of the new Nitrospirillum species. Additionally, MALDI-TOF MS analysis of whole-cell mass spectra provided further evidence for the differentiation of the proposed Nitrospirillum species, separate from N. amazonense. Analysis of chemotaxonomy markers (i.e., genes involved in fatty acid synthesis, metabolism and elongation, phospholipid synthesis, and quinone synthesis) revealed that the new species highlights high similarity and evolutionary convergence with other Nitrospirillum species. This new species exhibited nitrogen fixation ability in vitro, it has similar NifHDK protein phylogeny position with the closest species, lacked denitrification capability, but possessed the nosZ gene, enabling N2O reduction, distinguishing it from the closest species. Despite being isolated from diverse geographic regions, soil types, and ecological niches, no significant phenotypic or physiological differences were observed between the proposed new species and N. amazonense. Based on these findings, a new species, Nitrospirillum viridazoti sp. nov., was classified, with the strain BR 11140T (DSM 2788T, ATCC 35120T) designated as the type strain.


Asunto(s)
Nitrógeno , Poaceae , Filogenia , ARN Ribosómico 16S/genética , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
2.
Reprod Health ; 20(1): 167, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37957689

RESUMEN

BACKGROUND: Many low- and-middle-income countries are disproportionately burdened by cervical cancer, resulting in high morbidity and mortality. HPV-DNA testing coupled with treatment with thermal ablation is a recommended screening and precancer treatment strategy, but not enough is known about how this can be effectively implemented in the context of integrated services. The (Scale Up Cervical Cancer Elimination by Secondary prevention Strategy, (SUCCESS) project is conducting a study to understand this approach, integrated into existing women's health services in Burkina Faso, Cote d'Ivoire, Guatemala, and the Philippines (2020-2024). METHODS: A hybrid effectiveness-implementation type III mixed-methods observational study design is used to assess feasibility, acceptability, and costs of integrated service delivery in 10 sites per country, selected considering urban/rural location, facility level, onsite/offsite laboratories, and health services type. In each country, a sample size of 2227 women aged 25-49 years will be enrolled with about 20% being women living with HIV. The primary outcome is proportion of HPV positive women completing precancer treatment, if eligible, within three months of screening. Data collection and analysis includes; facility and client exit surveys, key informant and client interviews, registries and project records extractions, and costing data analysis. Analysis includes descriptive statistics, context description, thematic analysis, and document analysis. Quantitative analyses will be stratified by participant's HIV status. DISCUSSION: Recruitment of study participants started in April 2022 (Burkina Faso and Côte d'Ivoire) and August 2022 (Guatemala and the Philippines). Enrolment targets for women screened, client exit, in-depth and key informant interviews conducted were reached in Burkina Faso and Cote d'Ivoire in November 2022. Guatemala and Philippines are expected to complete enrolment by June 2023. Follow-up of study Participants 12-months post-treatment is ongoing and is expected to be completed for all countries by August 2024. In LMICs, integrating cervical cancer secondary prevention services into other health services will likely require specific rather than incidental recruitment of women for screening. Reconfiguration of laboratory infrastructure and planning for sample management must be made well in advance to meet induced demand for screening. Trail Registration ClinicalTrials.Gov ID: NCT05133661 (24/11/2021).


Asunto(s)
Infecciones por VIH , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Humanos , Femenino , Masculino , Côte d'Ivoire/epidemiología , Burkina Faso/epidemiología , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/prevención & control , Guatemala/epidemiología , Filipinas/epidemiología , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/prevención & control , Infecciones por VIH/prevención & control , Estudios Observacionales como Asunto
3.
Braz J Microbiol ; 54(4): 2627-2640, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37843794

RESUMEN

Endophytic diazotrophic plant growth-promoting bacteria Herbaspirillum rubrisubalbicans (HCC103), Herbaspirillum seropedicae (HRC54), Paraburkholderia tropica (Ppe8T), Gluconacetobacter diazotrophicus (Pal5T), and Nitrospirillum amazonense (CBAmC) have been used as inoculants for sugarcane. The genome sequences of these strains were used to design a set of specific primers for the real-time PCR (qPCR) assay. Primer specificity was confirmed by conventional PCR using the genomic DNAs of 25 related bacterial species and the five target strains. The qPCR assays were conducted using root and shoot samples from two sugarcane varieties (RB867515 and RB92579). These samples were collected both with and without inoculation, using the target strains specified in this study. The sugarcane plants were grown in a greenhouse, utilizing a substrate composed of sterile sand and vermiculite in a 2:1 ratio, for a duration of 55 days. The primers designed for this study successfully amplified target DNA fragments from each of the bacterial species, enabling their differentiation at the species level. The total bacterial population present in the sugarcane quantified using qPCR was on average 105.2 cells g-1 of fresh tissue. Across both evaluated varieties, it was observed that the population of inoculated bacteria tended to decrease over time and became more concentrated in the sugarcane roots compared to the aerial parts. The qPCR results suggest that both the host and the microbes influence the endophytic population and the bacterial number decreases with plant age.


Asunto(s)
Saccharum , Saccharum/microbiología , Reacción en Cadena en Tiempo Real de la Polimerasa
4.
Braz J Microbiol ; 54(4): 2915-2926, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37651089

RESUMEN

An inoculant containing selected bacterial strains can be easily applied during the nursery please process, but in this case, substrate composition can affect its survival and, in consequence, bacterial colonization. The aim of this study was to evaluate the survival of five diazotrophic bacterial strains/species applied individually on 13 different substrates used in sugarcane seedling nurseries considering an active population higher than 105 cells g-1. In addition, one experiment was performed using two commercial substrates, coconut fiber, and Multiplant™, inoculated or not with a mixture of five bacterial strains to evaluate plant growth after 30 days. These strains are combined inoculants selected for sugarcane acting as plant growth promoters. Bacterial counts were determined every seven days using the Most Probable Number technique with four different semi-solid N-free media specific for each strain tested over 35 days. The survival order, independent of the substrate tested, was: Paraburkholderia tropica Pt-PPe8T > Nitrospirillum amazonense Na-CBAMc > Herbaspirillum seropedicae Hs-HRC54 = H. rubrisubalbicans Hr-HCC103 > Gluconacetobacter diazotrophicus Gd-PAL5T. All tested substrates influenced the bacterial survival, especially after 21 days of incubation. The population size can be partially controlled by the substrate pH and stimulated by the addition of slow-release fertilizer. Besides the differences in the bacterial population present in the two commercial substrates, plant growth was found to be stimulated by the inoculated bacteria, depending on the substrate and its sugarcane cultivar tested. The selection of a substrate used to produce new plantlets of sugarcane can contribute to bacterial survival and improve bacterial colonization.


Asunto(s)
Saccharum , Plantones , Saccharum/microbiología , Bacterias
5.
Artículo en Inglés | MEDLINE | ID: mdl-35913881

RESUMEN

Strain Az39T of Azospirillum is a diazotrophic plant growth-promoting bacterium isolated in 1982 from the roots of wheat plants growing in Marcos Juárez, Córdoba, Argentina. It produces indole-3-acetic acid in the presence of l-tryptophan as a precursor, grows at 20-38 °C (optimal 38 °C), and the cells are curved or spiral-shaped, with diameters ranging from 0.5-0.9 to 1.8-2.2 µm. They contain C16 : 0, C18 : 0 and C18 : 1 ω7c/ω6c as the main fatty acids. Phylogenetic analysis of its 16S rRNA gene sequence confirmed that this strain belongs to the genus Azospirillum, showing a close relationship with Azospirillum baldaniorum Sp245T, Azospirillum brasilense Sp7T and Azospirillum formosense CC-Nfb-7T. Housekeeping gene analysis revealed that Az39T, together with five strains of the genus (Az19, REC3, BR 11975, MTCC4035 and MTCC4036), form a cluster apart from A. baldaniorum Sp245T, A. brasilense Sp7T and A. formosense CC-Nfb-7T. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) between Az39T and the aforementioned type strains revealed values below 96 %, the circumscription limit for the species delineation (ANI: 95.3, 94.1 and 94.0 %; dDDH: 62.9, 56.3 and 55.6 %). Furthermore, a phylogeny evaluation of the core proteome, including 809 common shared proteins, showed an independent grouping of Az39T, Az19, REC3, BR 11975, MTCC4035 and MTCC4036. The G+C content in the genomic DNA of these six strains varied from 68.3 to 68.5 %. Based on the combined phylogenetic, genomic and phenotypic characterization presented here, we consider that strain Az39T, along with strains Az19, REC3, BR 11975, MTCC4035 and MTCC4036, are members of a new Azospirillum species, for which the name Azospirillum argentinense sp. nov. is proposed. The type strain is Az39T (=LBPCV39T=BR 148428T=CCCT 22.01T).


Asunto(s)
Azospirillum brasilense , Azospirillum brasilense/genética , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Fosfolípidos/análisis , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/análisis
6.
Vaccine ; 40 Suppl 1: A116-A123, 2022 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-34863615

RESUMEN

A WHO global strategy launched in November 2020 sets out an ambitious pathway towards the worldwide elimination of cervical cancer as a public health problem within the next 100 years. Achieving this goal will require investment in innovative approaches. This review aims to describe integrated approaches that combine human papillomavirus (HPV) vaccination and cervical cancer screening in low- and middle-income countries (LMIC), and their efficacy in increasing uptake of services. A systematic review was conducted analyzing relevant papers from Embase, Medline, CINAHL and CAB Global Health databases, as well as grey literature. Narrative synthesis was performed on the included studies. Meta-analysis was not appropriate due to the heterogeneity and nature of included studies. From 5,278 titles screened, 11 uncontrolled intervention studies from four countries (from Africa and east Asia) were included, all from the past 12 years. Four distinct typologies of integration emerged that either increased awareness of HPV and/or cervical cancer screening, and/or coupled the delivery of HPV vaccination and cervical cancer screening programs. The synthesis of findings suggests that existing HPV vaccination programs can be a useful pathway for educating mothers and other female caregivers about cervical cancer screening; through in person conversations with care providers (preferred) or take-home communications products. Integrated service delivery through outreach and mobile clinics may overcome geographic and economic barriers to access for both HPV vaccination and cervical cancer screening, however these require significant program and system resources. One study promoted HPV vaccination as part of integrated service delivery, but there were no other examples found that examined use of cervical cancer screening platforms to promote or educate on HPV vaccination. This review has demonstrated gaps in published literature on attempts to integrate HPV vaccination and cervical cancer screening. The most promising practices to date seem to relate to integrated health communications for cervical cancer prevention. Future research should further explore the opportunities for integrated health communications to support the efforts towards the new global cervical cancer elimination agenda, and costs and feasibility of integrated service delivery for underserved populations.


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Neoplasias del Cuello Uterino , Cuello del Útero , Detección Precoz del Cáncer , Femenino , Humanos , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/uso terapéutico , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/prevención & control , Vacunación
7.
Int J Syst Evol Microbiol ; 70(12): 6203-6212, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33064068

RESUMEN

Azospirillum sp. strain Sp245T, originally identified as belonging to Azospirillum brasilense, is recognized as a plant-growth-promoting rhizobacterium due to its ability to fix atmospheric nitrogen and to produce plant-beneficial compounds. Azospirillum sp. Sp245T and other related strains were isolated from the root surfaces of different plants in Brazil. Cells are Gram-negative, curved or slightly curved rods, and motile with polar and lateral flagella. Their growth temperature varies between 20 to 38 °C and their carbon source utilization is similar to other Azospirillum species. A preliminary 16S rRNA sequence analysis showed that the new species is closely related to A. brasilense Sp7T and A. formosense CC-Nfb-7T. Housekeeping genes revealed that Azospirillum sp. Sp245T, BR 12001 and Vi22 form a separate cluster from strain A. formosense CC-Nfb-7T, and a group of strains closely related to A. brasilense Sp7T. Overall genome relatedness index (OGRI) analyses estimated based on average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) between Azospirillum sp. Sp245T and its close relatives to other Azospirillum species type strains, such as A. brasilense Sp7T and A. formosense CC-Nfb-7T , revealed values lower than the limit of species circumscription. Moreover, core-proteome phylogeny including 1079 common shared proteins showed the independent clusterization of A. brasilense Sp7T, A. formosense CC-Nfb-7T and Azospirillum sp. Sp245T, a finding that was corroborated by the genome clustering of OGRI values and housekeeping phylogenies. The DNA G+C content of the cluster of Sp245T was 68.4-68.6 %. Based on the phylogenetic, genomic, phenotypical and physiological analysis, we propose that strain Sp245T together with the strains Vi22 and BR12001 represent a novel species of the genus Azospirillum, for which the name Azospirillum baldaniorum sp. nov. is proposed. The type strain is Sp245T (=BR 11005T=IBPPM 219T) (GCF_007827915.1, GCF_000237365.1, and GCF_003119195.2).


Asunto(s)
Azospirillum brasilense/clasificación , Azospirillum/clasificación , Genoma Bacteriano , Filogenia , Técnicas de Tipificación Bacteriana , Composición de Base , Brasil , ADN Bacteriano/genética , Flagelos/química , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
8.
Arch Microbiol ; 201(4): 547-558, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30448870

RESUMEN

Maize is highly responsive to the application of nitrogen to achieve high productivity. Inoculation with diazotrophic bacteria can improve plant growth with low N fertilization. The objective was to evaluate the inoculation of two species of diazotrophs on N metabolism in maize plants, in the presence of two concentrations of nitrogen in a hydroponic system. A factorial arrangement composed of two N levels (3.0 and 0.3 mM), with the presence of Hs-Herbaspirillum seropedicae, and Ab-Azospirillum brasilense or not. The parameters used were dry mass; N, P, and K accumulation; nitrate reductase activity; soluble fractions in roots and leaves. The inoculation altered the N metabolism and promoted greater development of maize plants, as well as a higher accumulation of P and K in the shoots. A more intensive process of N assimilation was evidenced when the plants were inoculated with H. seropedicae, leading to increased levels of NO3- and reduced N-amino, sugars, and NH4+ in leaves associated with high N level, opposite of A. brasilense.


Asunto(s)
Azospirillum brasilense/fisiología , Herbaspirillum/fisiología , Nitrógeno/metabolismo , Zea mays/metabolismo , Zea mays/microbiología , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo
9.
Arch Microbiol ; 199(6): 863-873, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28321482

RESUMEN

Diazotrophs are able to stimulate plant growth. This study aimed at evaluating the effect of inoculation of five diazotrophic strains on growth promotion and nitrate reductase (NR, EC 1.7.1.1) activity in sugarcane. An experiment was carried out from three stages of cultivation: sprouting, tubes, and in hydroponics. On the first two stages, seven treatments were adopted: uninoculated control; mixed inoculation with five strains; and individual inoculation with Gluconacetobacter diazotrophicus (Gd), Herbaspirillum rubrisubalbicans (Hr), Herbaspirillum seropedicae (Hs), Nitrospirillum amazonense (Na), and Paraburkholderia tropica (Pt). The four treatments showing the best performance were transferred to the hydroponic system for analysis of NR activity. Hs, Pt, and the mixture of all strains led to the highest seedling biomass in tubes, followed by Hr. In hydroponics, the mixture and the strain Hr had the highest growth-promoting effect. NR activity was influenced by inoculation only under low N supply conditions, with positive effect of Hr, Pt, and the mixture.


Asunto(s)
Inoculantes Agrícolas/fisiología , Burkholderiaceae/fisiología , Gluconacetobacter/fisiología , Herbaspirillum/fisiología , Nitrato-Reductasa/metabolismo , Proteínas de Plantas/metabolismo , Rhodospirillaceae/fisiología , Saccharum/microbiología , Fijación del Nitrógeno , Saccharum/enzimología , Saccharum/crecimiento & desarrollo
10.
Int J Syst Evol Microbiol ; 66(10): 4118-4124, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27453319

RESUMEN

Root nodule bacteria were isolated from nodules on Mimosa pudica L. growing in neutral-alkaline soils from the Distrito Federal in central Brazil. The 16S rRNA gene sequence analysis of 10 strains placed them into the genus Rhizobium with the closest neighbouring species (each with 99 % similarity) being Rhizobium grahamii, Rhizobium cauense, Rhizobium mesoamericanum and Rhizobium tibeticum. This high similarity, however, was not confirmed by multi-locus sequence analysis (MLSA) using three housekeeping genes (recA, glnII and rpoB), which revealed R. mesoamericanum CCGE 501T to be the closest type strain (92 % sequence similarity or less). Chemotaxonomic data, including fatty acid profiles [with majority being C19 : 0 cyclo ω8c and summed feature 8 (C18 : 1ω7c/C18 : 1ω6c)], DNA G+C content (57.6 mol%), and carbon compound utilization patterns supported the placement of the novel strains in the genus Rhizobium. Results of average nucleotide identity (ANI) differentiated the novel strains from the closest species of the genus Rhizobium, R. mesoamericanum, R. grahamii and R. tibeticum with 89.0, 88.1 and 87.8 % similarity, respectively. The symbiotic genes essential for nodulation (nodC) and nitrogen fixation (nifH) were most similar (99-100 %) to those of R. mesoamericanum, another Mimosa-nodulating species. Based on the current data, these 10 strains represent a novel species of the genus Rhizobium for which the name Rhizobium altiplani sp. nov. is proposed. The type strain is BR 10423T (=HAMBI 3664T).


Asunto(s)
Mimosa/microbiología , Filogenia , Rhizobium/clasificación , Nódulos de las Raíces de las Plantas/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , Brasil , ADN Bacteriano/genética , Ácidos Grasos/química , Genes Bacterianos , Fijación del Nitrógeno , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Rhizobium/genética , Rhizobium/aislamiento & purificación , Análisis de Secuencia de ADN , Suelo/química , Simbiosis
11.
BMC Pregnancy Childbirth ; 15: 306, 2015 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-26596353

RESUMEN

BACKGROUND: Poor quality of care at health facilities is a barrier to pregnant women and their families accessing skilled care. Increasing evidence from low resource countries suggests care women receive during labor and childbirth is sometimes rude, disrespectful, abusive, and not responsive to their needs. However, little is known about how frequently women experience these behaviors. This study is one of the first to report prevalence of respectful maternity care and disrespectful and abusive behavior at facilities in multiple low resource countries. METHODS: Structured, standardized clinical observation checklists were used to directly observe quality of care at facilities in five countries: Ethiopia, Kenya, Madagascar, Rwanda, and the United Republic of Tanzania. Respectful care was represented by 10 items describing actions the provider should take to ensure the client was informed and able to make choices about her care, and that her dignity and privacy were respected. For each country, percentage of women receiving these practices and delivery room privacy conditions were calculated. Clinical observers' open-ended comments were also analyzed to identify examples of disrespect and abuse. RESULTS: A total of 2164 labor and delivery observations were conducted at hospitals and health centers. Encouragingly, women overall were treated with dignity and in a supportive manner by providers, but many women experienced poor interactions with providers and were not well-informed about their care. Both physical and verbal abuse of women were observed during the study. The most frequently mentioned form of disrespect and abuse in the open-ended comments was abandonment and neglect. CONCLUSIONS: Efforts to increase use of facility-based maternity care in low income countries are unlikely to achieve desired gains if there is no improvement in quality of care provided, especially elements of respectful care. This analysis identified insufficient communication and information sharing by providers as well as delays in care and abandonment of laboring women as deficiencies in respectful care. Failure to adopt a patient-centered approach and a lack of health system resources are contributing structural factors. Further research is needed to understand these barriers and develop effective interventions to promote respectful care in this context.


Asunto(s)
Actitud del Personal de Salud , Parto Obstétrico , Servicios de Salud Materna/normas , Relaciones Profesional-Paciente , Derechos de la Mujer , Lista de Verificación , Estudios Transversales , Etiopía , Femenino , Humanos , Kenia , Madagascar , Aceptación de la Atención de Salud , Pobreza , Embarazo , Rwanda , Encuestas y Cuestionarios , Tanzanía
12.
J Basic Microbiol ; 55(8): 931-49, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25736602

RESUMEN

For centuries, the Acetobacteraceae is known as a family that harbors many species of organisms of biotechnological importance for industry. Nonetheless, since 1988 representatives of this family have also been described as nitrogen fixing bacteria able to plant growth promotion by a variety of mechanisms. Nitrogen fixation is a biological process that guarantees that the atmospheric N2 is incorporated into organic matter by several bacterial groups. Most representatives of this group, also known as diazotrophic, are generally associated with soil rhizosphere of many plants and also establishing a more specific association living inside roots, leaves, and others plants tissues as endophyte. Their roles as plant growth-promoting microorganisms are generally related to increase in plant biomass, phosphate and other mineral solubilization, and plant pathogen control. Here, we report many of these plant growth-promoting processes related to nitrogen fixing species already described in Acetobacteraceae family, especially Gluconacetobacter diazotrophicus and their importance to agriculture. In addition, a brief review of the state of art of the phylogenetics, main physiological and biochemical characteristics, molecular and functional genomic data of this group of Acetobacteraceae is presented.


Asunto(s)
Acetobacteraceae/genética , Acetobacteraceae/fisiología , Agricultura , Gluconacetobacter/fisiología , Fijación del Nitrógeno , Microbiología del Suelo , Biomasa , Endófitos , Filogenia , Hojas de la Planta/microbiología , Raíces de Plantas/microbiología , Rizosfera
13.
Environ Microbiol Rep ; 6(4): 354-63, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24992534

RESUMEN

Brazilian sugarcane has been shown to obtain part of its nitrogen via biological nitrogen fixation (BNF). Recent reports, based on the culture independent sequencing of bacterial nifH complementary DNA (cDNA) from sugarcane tissues, have suggested that members of the Bradyrhizobium genus could play a role in sugarcane-associated BNF. Here we report on the isolation of Bradyrhizobium spp. isolates and a few other species from roots of sugarcane cultivar RB867515 by two cultivation strategies: direct isolation on culture media and capture of Bradyrhizobium spp. using the promiscuous legume Vigna unguiculata as trap-plant. Both strategies permitted the isolation of genetically diverse Bradyrhizobium spp. isolates, as concluded from enterobacterial repetitive intergenic consensus polymerase chain reaction (PCR) fingerprinting and 16S ribosomal RNA, nifH and nodC sequence analyses. Several isolates presented nifH phylotypes highly similar to nifH cDNA phylotypes detected in field-grown sugarcane by a culture-independent approach. Four isolates obtained by direct plate cultivation were unable to nodulate V. unguiculata and, based on PCR analysis, lacked a nodC gene homologue. Acetylene reduction assay showed in vitro nitrogenase activity for some Bradyrhizobium spp. isolates, suggesting that these bacteria do not require a nodule environment for BNF. Therefore, this study brings further evidence that Bradyrhizobium spp. may play a role in sugarcane-associated BNF under field conditions.


Asunto(s)
Bradyrhizobium/clasificación , Bradyrhizobium/aislamiento & purificación , Endófitos/clasificación , Endófitos/aislamiento & purificación , Saccharum/microbiología , Proteínas Bacterianas/genética , Bradyrhizobium/genética , Bradyrhizobium/crecimiento & desarrollo , Brasil , Análisis por Conglomerados , Medios de Cultivo/química , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Endófitos/genética , Endófitos/crecimiento & desarrollo , Técnicas Microbiológicas , Datos de Secuencia Molecular , Tipificación Molecular , Nitrogenasa/análisis , Filogenia , Nodulación de la Raíz de la Planta , Raíces de Plantas/microbiología , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
14.
Psychosom Med ; 76(1): 2-11, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24336429

RESUMEN

OBJECTIVE: This meta-analysis systematically examined the association of reported psychological trauma and posttraumatic stress disorder (PTSD) with functional somatic syndromes including fibromyalgia, chronic widespread pain, chronic fatigue syndrome, temporomandibular disorder, and irritable bowel syndrome. Our goals were to determine the overall effect size of the association and to examine moderators of the relationship. METHODS: Literature searches identified 71 studies with a control or comparison group and examined the association of the syndromes with traumatic events including abuse of a psychological, emotional, sexual, or physical nature sustained during childhood or adulthood, combat exposure, or PTSD. A random-effects model was used to estimate the pooled odds ratio and 95% confidence interval. Planned subgroup analyses and meta-regression examined potential moderators. RESULTS: Individuals who reported exposure to trauma were 2.7 (95% confidence interval = 2.27-3.10) times more likely to have a functional somatic syndrome. This association was robust against both publication bias and the generally low quality of the literature. The magnitude of the association with PTSD was significantly larger than that with sexual or physical abuse. The association of reported trauma with chronic fatigue syndrome was larger than the association with either irritable bowel syndrome or fibromyalgia. Studies using nonvalidated questionnaires or self-report of trauma reported larger associations than did those using validated questionnaires. CONCLUSIONS: Findings are consistent with the hypothesis that traumatic events are associated with an increased prevalence of functional somatic syndromes. The analyses also highlight limitations of the existing literature and emphasize the importance of prospective studies, examining the potential similarities and differences of these conditions, and pursuing hypothesis-driven studies of the mechanisms underlying the link between trauma, PTSD, and functional somatic syndromes.


Asunto(s)
Dolor Crónico/epidemiología , Síndrome del Colon Irritable/epidemiología , Enfermedades Neuromusculares/epidemiología , Trastornos por Estrés Postraumático/epidemiología , Trastornos de la Articulación Temporomandibular/epidemiología , Dolor Crónico/etiología , Humanos , Síndrome del Colon Irritable/etiología , Enfermedades Neuromusculares/etiología , Trastornos por Estrés Postraumático/complicaciones , Trastornos de la Articulación Temporomandibular/etiología
15.
J Microbiol Methods ; 91(1): 1-7, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22814372

RESUMEN

Gluconacetobacter diazotrophicus strain PAL5 is a nitrogen-fixing endophytic bacterium originally isolated from sugarcane and later on was found to colonize other plants such as rice, elephant grass, sweet potato, coffee, and pineapple. Currently, G. diazotrophicus has been considered a plant growth-promoting bacterium due to its characteristics of biological nitrogen fixation, phytohormone secretion, solubilization of mineral nutrients and antagonism to phytopathogens. Reverse transcription followed by quantitative real-time polymerase chain reaction (RT-qPCR) is a method applied for the quantification of nucleic acids because of its specificity and high sensitivity. However, the decision about the reference genes suitable for data validation is still a major issue, especially for nitrogen-fixing bacteria. To evaluate and identify suitable reference genes for gene expression normalization in the diazotrophic G. diazotrophicus, mRNA levels of fourteen candidate genes (rpoA, rpoC, recA, rpoD, fabD, gmk, recF, rho, ldhD, gyrB, gyrBC, dnaG, lpxC and 23SrRNA) and three target genes (matE, omp16 and sucA) were quantified by RT-qPCR after growing the bacteria in different carbon sources. The geNorm and Normfinder programs were used to calculate the expression stabilities. The analyses identified three genes, rho, 23SrRNA and rpoD, whose expressions were stable throughout the growth of strain PAL5 in the chosen carbon sources. In conclusion our results strongly suggest that these three genes are suitable to be used as reference genes for real-time RT-qPCR data normalization in G. diazotrophicus.


Asunto(s)
Carbono/metabolismo , Perfilación de la Expresión Génica/métodos , Gluconacetobacter/genética , Gluconacetobacter/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Estándares de Referencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Perfilación de la Expresión Génica/normas , Genes Bacterianos , Gluconacetobacter/crecimiento & desarrollo , Reacción en Cadena en Tiempo Real de la Polimerasa/normas
16.
J Psychosom Res ; 72(1): 39-44, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22200521

RESUMEN

OBJECTIVE: To examine health, psychological, and autonomic impairment differences between individuals with fibromyalgia and those with other chronic benign pain in these conditions. The possible role of the autonomic nervous system in the maintenance of chronic benign pain can be examined using heart rate variability (HRV), which measures the interplay between the excitatory sympathetic and the inhibitory parasympathetic nervous system. Predictors of HRV will also be examined. METHODS: This study examined resting HRV in a sample of 84 patients with chronic benign pain, a subgroup of whom had fibromyalgia. Participants completed a battery of self-report measures and underwent measurements of resting HRV. RESULTS: Individuals with fibromyalgia experienced higher levels of depression (t (82)=-2.27, p<.05) and significantly greater difficulty with physical functioning (t (75.8)=2.65, p<.01) than did those with other chronic benign pain, there were no significant differences in any of the HRV indices. Across all pain conditions, we found that age, gender, physical health functioning, pain anxiety, and pain sensations were all significant predictors of HRV, suggesting that each are involved in the relationship between chronic benign pain and autonomic function. CONCLUSIONS: These findings emphasize the importance of addressing psychological distress and physical functioning in chronic pain populations and specifically fibromyalgia. Future research can further examine the role of physical health functioning, psychological distress, and pain severity in the relationship between chronic pain and autonomic abnormalities.


Asunto(s)
Sistema Nervioso Autónomo/fisiopatología , Dolor Crónico/fisiopatología , Fibromialgia/fisiopatología , Frecuencia Cardíaca/fisiología , Estrés Psicológico/fisiopatología , Adulto , Anciano , Dolor Crónico/psicología , Femenino , Fibromialgia/psicología , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Estrés Psicológico/psicología , Encuestas y Cuestionarios
17.
Environ Microbiol Rep ; 3(3): 383-9, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23761284

RESUMEN

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.

18.
Braz. j. microbiol ; 40(4): 866-878, Oct.-Dec. 2009. graf, tab
Artículo en Inglés | LILACS | ID: lil-528169

RESUMEN

The species Gluconacetobacter diazotrophicus, Herbaspirillum seropedicae and H. rubrisubalbicans are endophytic N2-fixing [diazotrophic] bacteria which colonise not only roots, but also the aerial tissue of sugar cane. However, the technique most commonly used to quantify the populations of these microbes in plants is by culturing serial dilutions of macerates of plant tissues in N free semi-solid media which are only semi-selective for the species/genera [the Most Probable Number (MPN) Technique] and each culture must be further subjected to several tests to identify the isolates at the species level. The use of species-specific polyclonal antibodies with the indirect ELISA (enzyme-linked immunosorbent assay) can be an alternative which is rapid and specific to quantify these populations of bacteria. This study was performed to investigate the viability of adapting the indirect ELISA technique to quantify individually the populations of these three species of diazotroph within the root and shoot tissues of sugarcane. The results showed that species-specific polyclonal antibodies could be obtained by purifying sera in protein-A columns which removed non-specific immuno-globulins. It was possible to quantify the three bacterial species in the Brazilian sugarcane variety SP 70-1143 in numbers above 10(5) cells per g fresh weight in roots, rhizomes and leaves. The numbers of the different bacterial species evaluated using the ELISA technique were found to be higher than when the same populations were evaluated using the MPN technique, reaching 1400 times greater for G. diazotrophicus and 225 times greater for Herbaspirillum spp. These results constitute the first quantification of Herbaspirillum using immunological techniques.


Asunto(s)
Anticuerpos/análisis , Gluconacetobacter/aislamiento & purificación , Herbaspirillum/aislamiento & purificación , Fijación del Nitrógeno , Saccharum , Ensayo de Inmunoadsorción Enzimática , Técnicas Inmunológicas , Métodos
19.
J Gen Intern Med ; 24(11): 1192-7, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19774423

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths in the United States. Randomized controlled trials have shown that annual screening fecal occult blood testing (FOBT) reduces CRC mortality and incidence. However, patient compliance with FOBT is low. OBJECTIVE: To determine whether a mailed educational reminder increases FOBT card return rates and to examine predictors of FOBT compliance. DESIGN: Blinded, randomized, controlled trial at the Veteran Affairs Medical Center, San Diego, California. PATIENTS: Seven hundred and seventy-five consecutive patients > or =50 years of age referred by their primary care physicians for FOBT. INTERVENTION: Patients were randomly assigned to the usual care group or the intervention group. Ten days after picking up the FOBT cards, a 1-page reminder with information related to CRC screening was mailed to the intervention group only. MEASUREMENTS: The primary outcome was proportion of returned FOBT cards after 6 months. Patient demographic, clinical characteristics and prior FOBT completed were collected for multivariate regression analysis. RESULTS: At 6 months after card distribution, 64.6% of patients in the intervention group returned cards compared with 48.4% in the control group (P < 0.001). Patients who received a mailed reminder (OR 2.02; 95% CI: 1.48-2.74) or have a prior history of returning the FOBT cards (OR 1.87; 95% CI: 1.29-2.70) were more likely to return the FOBT cards. Patients with current or recent illicit drug use were less likely to return the FOBT cards (OR 0.26; 95% CI: 0.13-0.50). CONCLUSION: A simple mailed educational reminder significantly increases compliance with FOBT for CRC screening.


Asunto(s)
Detección Precoz del Cáncer/métodos , Sangre Oculta , Cooperación del Paciente , Educación del Paciente como Asunto/métodos , Servicios Postales/métodos , Sistemas Recordatorios , Anciano , Citas y Horarios , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/prevención & control , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad
20.
Braz J Microbiol ; 40(4): 866-78, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24031435

RESUMEN

The species Gluconacetobacter diazotrophicus, Herbaspirillum seropedicae and H. rubrisubalbicans are endophytic N2-fixing [diazotrophic] bacteria which colonise not only roots, but also the aerial tissue of sugar cane. However, the technique most commonly used to quantify the populations of these microbes in plants is by culturing serial dilutions of macerates of plant tissues in N free semi-solid media which are only semi-selective for the species/genera [the Most Probable Number (MPN) Technique] and each culture must be further subjected to several tests to identify the isolates at the species level. The use of species-specific polyclonal antibodies with the indirect ELISA (enzyme-linked immunosorbent assay) can be an alternative which is rapid and specific to quantify these populations of bacteria. This study was performed to investigate the viability of adapting the indirect ELISA technique to quantify individually the populations of these three species of diazotroph within the root and shoot tissues of sugarcane. The results showed that species-specific polyclonal antibodies could be obtained by purifying sera in protein-A columns which removed non-specific immuno-globulins. It was possible to quantify the three bacterial species in the Brazilian sugarcane variety SP 70-1143 in numbers above 10(5) cells per g fresh weight in roots, rhizomes and leaves. The numbers of the different bacterial species evaluated using the ELISA technique were found to be higher than when the same populations were evaluated using the MPN technique, reaching 1400 times greater for G. diazotrophicus and 225 times greater for Herbaspirillum spp. These results constitute the first quantification of Herbaspirillum using immunological techniques.

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