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71.
72.
Costa R Gomes NC Krögerrecklenfort E Opelt K Berg G Smalla K 《Environmental microbiology》2007,9(9):2260-2273
The Pseudomonas community structure and antagonistic potential in the rhizospheres of strawberry and oilseed rape (host plants of the fungal phytopathogen Verticillium dahliae) were assessed. The use of a new PCR-DGGE system, designed to target Pseudomonas-specific gacA gene fragments in environmental DNA, circumvented common biases of 16S rRNA gene-based DGGE analyses and proved to be a reliable tool to unravel the diversity of uncultured Pseudomonas in bulk and rhizosphere soils. Pseudomonas-specific gacA fingerprints of total-community (TC) rhizosphere DNA were surprisingly diverse, plant-specific and differed markedly from those of the corresponding bulk soils. By combining multiple culture-dependent and independent surveys, a group of Pseudomonas isolates antagonistic towards V. dahliae was shown to be genotypically conserved, to carry the phlD biosynthetic locus (involved in the biosynthesis of 2,4-diacetylphloroglucinol - 2,4-DAPG), and to correspond to a dominant and highly frequent Pseudomonas population in the rhizosphere of field-grown strawberries planted at three sites in Germany which have different land use histories. This population belongs to the Pseudomonas fluorescens phylogenetic lineage and showed closest relatedness to P. fluorescens strain F113 (97% gacA gene sequence identity in 492-bp sequences), a biocontrol agent and 2,4-DAPG producer. Partial gacA gene sequences derived from isolates, clones of the strawberry rhizosphere and DGGE bands retrieved in this study represent previously undescribed Pseudomonas gacA gene clusters as revealed by phylogenetic analysis. 相似文献
73.
A new semi-nested PCR protocol to amplify large 18S rRNA gene fragments for PCR-DGGE analysis of soil fungal communities 总被引:4,自引:0,他引:4
The analysis of soil fungal communities by molecular fingerprinting and subsequent identification of the underlying populations require the amplification of a phylogenetically informative gene fragment. In this study we tested the reliability and suitability of the previously published fungal primer combination (NS1/FR1-GC) that amplifies almost the entire 18S rRNA gene for the DGGE analysis of fungal communities in soil samples from 36 sites. This direct PCR system failed to amplify the fragment of interest from the total DNA extracted from most of the soils tested. Thus, we developed a new semi-nested PCR system based on the initial amplification of over 1,700 bp of the 18S rRNA gene with a new primer combination, followed by a subsequent amplification with NS1/FR1-GC. By means of the PCR approach developed in this study distinct 18S rRNA gene amplicons could be reproducibly generated for all soil samples. Amplification tests with 101 soil fungal isolates showed that with the new semi-nested system 18S rRNA gene fragments could be obtained from more fungi than with the direct approach. The subsequent DGGE separation of community amplicons resulted in a high resolution and revealed reproducible complex soil fungal communities specific for each site, despite a minor variability between replicates of the same sample. The semi-nested PCR system developed in this study, coupled with DGGE fingerprinting, offers a robust, reliable and sensitive tool for the analysis of soil fungal community structure. 相似文献
74.
75.
Human immunodeficiency virus (HIV-1) has become an important risk factor for human papillomavirus (HPV) infection and the development of HPV associated lesions in the female genital tract. HIV-1 may also increase the oncogenicity of high risk HPV types and the activation of low risk types. The Center for Disease Control and Prevention declared invasive cervical cancer an acquired immunodeficiency virus (AIDS) defining illness in HIV positive women. Furthermore, cervical cancer happens to be the second most common female cancer worldwide. The host's local immune response plays a critical factor in controlling these conditions, as well as in changes in the number of professional antigen-presenting cells, cytokine, and MHC molecules expression. Also, the production of cytokines may determine which arm of the immune response will be stimulated and may influence the magnitude of immune protection. Although there are many studies describing the inflammatory response in HPV infection, few data are available to demonstrate the influence of the HIV infection and several questions regarding the cervical immune response are still unknown. In this review we present a brief account of the current understanding of HIV/HPV co-infection, emphasizing cervical immune response. 相似文献
76.
The FEN1 nuclease functions during Okazaki fragment maturation in the eukaryotic cell. Like many other proliferating cell nuclear antigen (PCNA)-binding proteins, FEN1 interacts with the interdomain connector loop (IDCL) of PCNA, and PCNA greatly stimulates FEN1 activity. A yeast IDCL mutant pcna-79 (IL126,128AA) failed to interact with FEN-1, but, surprisingly, pcna-79 was still very active in stimulating FEN1 activity. In contrast, a C-terminal mutant pcna-90 (PK252,253AA) showed wild-type binding to FEN1 in solution, but poorly stimulated FEN1 activity. When PCNA was loaded onto a DNA substrate coupled to magnetic beads, it stabilized retention of FEN1 on the DNA. In this DNA-dependent binding assay, pcna-79 also stabilized retention of FEN1, but pcna-90 was inactive. Therefore, in the absence of DNA, FEN1 interacts with PCNA mainly through the IDCL. However, when PCNA encircles the DNA, the C-terminal domain of PCNA rather than its IDCL is important for binding FEN1. An FF-->GA mutation in the PCNA-interaction domain of FEN1 severely decreased both modes of interaction with PCNA and resulted in replication and repair defects in vivo. 相似文献
77.
Roberta Gomes Carvalho Ricardo Louren?o-de-Oliveira Ima Aparecida Braga 《Memórias do Instituto Oswaldo Cruz》2014,109(6):787-796
The geographical distribution of Aedes albopictus in Brazil was updated according tothe data recorded across the country over the last eight years. Countrywide houseindexes (HI) for Ae. albopictus in urban and suburban areas were described for thefirst time using a sample of Brazilian municipalities. This mosquito is currentlypresent in at least 59% of the Brazilian municipalities and in 24 of the 27 federalunits (i.e., 26 states and the Federal District). In 34 Brazilian municipalities, theHI values for Ae. albopictus were higher than those recorded for Ae. aegypti,reaching figures as high as HI = 7.72 in the Southeast Region. Remarks regarding thecurrent range of this mosquito species in the Americas are also presented. NineteenAmerican countries are currently infested and few mainland American countries havenot confirmed the occurrence of Ae. albopictus. The large distribution and highfrequency of Ae. albopictus in the Americas may become a critical factor in thespread of arboviruses like chikungunya in the new world. 相似文献
78.
Luciano Pamplona de Góes Cavalcanti Lia Alves Martins Mota Gustavo Porto Lustosa Mayara Carvalho Fortes Davi Alves Martins Mota Ant?nio Afonso Bezerra Lima Ivo Castelo Branco Coelho Maria Paula Gomes Mour?o 《Memórias do Instituto Oswaldo Cruz》2014,109(1):93-98
In 2009, the World Health Organization (WHO) issued a new guideline that stratifies
dengue-affected patients into severe (SD) and non-severe dengue (NSD) (with or
without warning signs). To evaluate the new recommendations, we completed a
retrospective cross-sectional study of the dengue haemorrhagic fever (DHF) cases
reported during an outbreak in 2011 in northeastern Brazil. We investigated 84
suspected DHF patients, including 45 (53.6%) males and 39 (46.4%) females. The ages
of the patients ranged from five-83 years and the median age was 29. According to the
DHF/dengue shock syndrome classification, 53 (63.1%) patients were classified as
having dengue fever and 31 (36.9%) as having DHF. According to the 2009 WHO
classification, 32 (38.1%) patients were grouped as having NSD [4 (4.8%) without
warning signs and 28 (33.3%) with warning signs] and 52 (61.9%) as having SD. A
better performance of the revised classification in the detection of severe clinical
manifestations allows for an improved detection of patients with SD and may reduce
deaths. The revised classification will not only facilitate effective screening and
patient management, but will also enable the collection of standardised surveillance
data for future epidemiological and clinical studies. 相似文献
79.
Stacey Llewellyn Tawin Inpankaew Susana Vaz Nery Darren J. Gray Jaco J. Verweij Archie C. A. Clements Santina J. Gomes Rebecca Traub James S. McCarthy 《PLoS neglected tropical diseases》2016,10(1)
Background
Accurate quantitative assessment of infection with soil transmitted helminths and protozoa is key to the interpretation of epidemiologic studies of these parasites, as well as for monitoring large scale treatment efficacy and effectiveness studies. As morbidity and transmission of helminth infections are directly related to both the prevalence and intensity of infection, there is particular need for improved techniques for assessment of infection intensity for both purposes. The current study aimed to evaluate two multiplex PCR assays to determine prevalence and intensity of intestinal parasite infections, and compare them to standard microscopy.Methodology/Principal Findings
Faecal samples were collected from a total of 680 people, originating from rural communities in Timor-Leste (467 samples) and Cambodia (213 samples). DNA was extracted from stool samples and subject to two multiplex real-time PCR reactions the first targeting: Necator americanus, Ancylostoma spp., Ascaris spp., and Trichuris trichiura; and the second Entamoeba histolytica, Cryptosporidium spp., Giardia. duodenalis, and Strongyloides stercoralis. Samples were also subject to sodium nitrate flotation for identification and quantification of STH eggs, and zinc sulphate centrifugal flotation for detection of protozoan parasites. Higher parasite prevalence was detected by multiplex PCR (hookworms 2.9 times higher, Ascaris 1.2, Giardia 1.6, along with superior polyparasitism detection with this effect magnified as the number of parasites present increased (one: 40.2% vs. 38.1%, two: 30.9% vs. 12.9%, three: 7.6% vs. 0.4%, four: 0.4% vs. 0%). Although, all STH positive samples were low intensity infections by microscopy as defined by WHO guidelines the DNA-load detected by multiplex PCR suggested higher intensity infections.Conclusions/Significance
Multiplex PCR, in addition to superior sensitivity, enabled more accurate determination of infection intensity for Ascaris, hookworms and Giardia compared to microscopy, especially in samples exhibiting polyparasitism. The superior performance of multiplex PCR to detect polyparasitism and more accurately determine infection intensity suggests that it is a more appropriate technique for use in epidemiologic studies and for monitoring large-scale intervention trials. 相似文献80.
Development and Validation of the Self-Acceptance Scale for Persons with Early Blindness: The SAS-EB
Fabiane Frota da Rocha Morgado Angela Nogueira Neves Betanho Campana Maria da Consola??o Gomes Cunha Fernandes Tavares 《PloS one》2014,9(9)
Investigations of self-acceptance are critical to understanding the development and maintenance of psychological health. However, valid and reliable instruments for measuring self-acceptance in persons with early blindness have yet to be developed. The current research describes three studies designed to develop and validate the Self-acceptance Scale for Persons with Early Blindness (SAS-EB). In Study 1, we developed the initial item pool. Thirty-three items were generated, based on data from specialized literature and from 2 focus groups. Items were organized in a three-factor structure, theoretically predicted for SAS-EB - (1) body acceptance, (2) self-protection from social stigmas, and (3) feeling and believing in one''s capacities. In Study 2, information obtained from a panel of 9 experts and 22 persons with early blindness representing the target population was used to refine the initial item pool, generating a new pool of 27 items. In Study 3, 318 persons with early blindness (141 women and 177 men), between 18 and 60 years of age (M = 37.74 years, SD = 12.37) answered the new pool of 27 items. After the elimination of 9 items using confirmatory factor analysis, we confirmed the theoretical three-factor structure of the SAS-EB. Study 3 also provided support for the scale''s internal consistency and construct validity. Finally, the psychometric properties of the SAS-EB, its utility, and its limitations are discussed along with considerations for future research. 相似文献