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91.
Caleja C de Toro M Gon?alves A Themudo P Vieira-Pinto M Monteiro D Rodrigues J Sáenz Y Carvalho C Igrejas G Torres C Poeta P 《International microbiology》2011,14(1):19-24
The antibiotic resistance phenotype and genotype and the integron type were characterized in 58 Salmonella enterica isolates recovered from Bísaro pigs and wild boars (20 S. Typhimurium, 17 S. Rissen, 14 S. Enteritidis and 7 S. Havana). Most S. Typhimurium isolates (15/20 of Bísaro pigs and wild boars) showed ampicillin, chloramphenicol, streptomycin, tetracycline, sulfonamide, and amoxicillin-clavulanic acid resistances. Of the 17 S. Rissen isolates of both origins, 13 were resistant to ampicillin, tetracycline and trimethoprim-sulfamethoxazole. Among the S. Enteritidis isolates of Bísaro pigs, eight were nalidixic acid-resistant and three were sulfonamide-resistant. The tet(A) or tet(G) genes were detected in most tetracycline-resistant isolates. The intI1 gene was identified in 72.5% of S. enterica isolates in which the conserved region 3' of class 1 integrons (qacEΔ1+sul1) was also amplified, whereas none had the intI2 gene. The dfrA12+orfF+aadA2 gene cassette arrangement was found in the variable region of class 1 integrons in 14 S. Rissen isolates. Fifteen S. Typhimurium isolates had two integrons with variable regions of 1000 and 1200 bp that harbored the aadA2 and blaPSE-1 gene cassettes, respectively. In these isolates the floR and tet(G) genes were also amplified, indicative of the genomic island 1 (SGI1). Salmonella Typhimurium and S. Rissen of animal origin frequently show a multi-antimicrobial resistant phenotype, which may have implications in public health. 相似文献
92.
Hasegawa M Fujimoto Y Lucas PC Nakano H Fukase K Núñez G Inohara N 《The EMBO journal》2008,27(2):373-383
Nod1 and Nod2 are intracellular proteins that are involved in host recognition of specific bacterial molecules and are genetically associated with several inflammatory diseases. Nod1 and Nod2 stimulation activates NF-kappaB through RICK, a caspase-recruitment domain-containing kinase. However, the mechanism by which RICK activates NF-kappaB in response to Nod1 and Nod2 stimulation is unknown. Here we show that RICK is conjugated with lysine-63-linked polyubiquitin chains at lysine 209 (K209) located in its kinase domain upon Nod1 or Nod2 stimulation and by induced oligomerization of RICK. Polyubiquitination of RICK at K209 was essential for RICK-mediated IKK activation and cytokine/chemokine secretion. However, RICK polyubiquitination did not require the kinase activity of RICK or alter the interaction of RICK with NEMO, a regulatory subunit of IkappaB kinase (IKK). Instead, polyubiquitination of RICK was found to mediate the recruitment of TAK1, a kinase that was found to be essential for Nod1-induced signaling. Thus, RICK polyubiquitination links TAK1 to IKK complexes, a critical step in Nod1/Nod2-mediated NF-kappaB activation. 相似文献
93.
Alves Leticia Rodrigues Rossatto Davi Rodrigo Rossi Mônica Lanzoni Martinelli Adriana Pinheiro Gratão Priscila Lupino 《Protoplasma》2020,257(2):597-605
Protoplasma - The application of Se to plants growing under Cd contamination may become an alternative strategy to minimize Cd damage. However, there is no specific information available regarding... 相似文献
94.
Surprising invariance relationships have emerged from the study of social interaction, whereby a cancelling‐out of multiple partial effects of genetic, ecological or demographic parameters means that they have no net impact upon the evolution of a social behaviour. Such invariants play a pivotal role in the study of social adaptation: on the one hand, they provide theoretical hypotheses that can be empirically tested; and, on the other hand, they provide benchmark frameworks against which new theoretical developments can be understood. Here we derive a novel invariant for dispersal evolution: the ‘constant philopater hypothesis’ (CPH). Specifically, we find that, irrespective of variation in maternal fecundity, all mothers are favoured to produce exactly the same number of philopatric offspring, with high‐fecundity mothers investing proportionally more, and low‐fecundity mothers investing proportionally less, into dispersing offspring. This result holds for female and male dispersal, under haploid, diploid and haplodiploid modes of inheritance, irrespective of the sex ratio, local resource availability and whether mother or offspring controls the latter's dispersal propensity. We explore the implications of this result for evolutionary conflict of interests – and the exchange and withholding of contextual information – both within and between families, and we show that the CPH is the fundamental invariant that underpins and explains a wider family of invariance relationships that emerge from the study of social evolution. 相似文献
95.
Lanzarotti E Pellizza L Bercovich A Foti M Coria SH Vazquez SC Ruberto L Hernández EA Dias RL Mac Cormack WP Cicero DO Smal C Nicolas MF Vasconcelos AT Marti MA Turjanski AG 《Journal of bacteriology》2011,193(23):6797-6798
A psychrotolerant marine bacterial strain, designated JUB59(T), was isolated from Antarctic surface seawater and classified as a new species of the genus Bizionia. Here, we present the first draft genome sequence for this genus, which suggests interesting features such as UV resistance, hydrolytic exoenzymes, and nitrogen metabolism. 相似文献
96.
Dener Acosta de Assis Carla Matte Bruno Aschidamini Eliseu Rodrigues Marco Antônio Záchia Ayub 《Biotechnology progress》2020,36(5):e3011
Vitamin B12 deficiency still persists, mainly caused by low intake of animal food products affecting vegetarians, vegans, and populations of underdeveloped countries. In this study, we investigate the biosynthesis of vitamin B12 by potential probiotic bacterium using an agroindustry residue, the liquid acid protein residue of soybean (LAPRS), as a low-cost, animal derivate-free alternative culture medium. Cultures of Propionibacterium freudenreichii subsp. shermanii ATCC 13673 growing in LAPRS for vitamin B12 biosynthesis were studied using the Plackett–Burman experimental approach, followed by a central composite design 22 to optimize the concentration of significant variables. We also performed a proteolytic treatment of LAPRS and evaluated the optimized–hydrolyzed medium influence on the microbial growth and metabolism in shaker flask and bioreactor experiments. In this all-plant source medium, P. freudenreichii subsp. shermanii produced high concentrations of cells and high amounts of vitamin B12 (0.6 mg/g cells) after process optimization. These results suggest the possibility of producing vitamin B12 by a potential probiotic bacterium in a very cheap, animal derivate-free medium to address the needs of specific population groups, at the same time reducing the production costs of this essential vitamin. 相似文献
97.
Patricia Fagundes Costa Geisa Ferreira Fernandes Priscila Oliveira dos Santos Cristiane Candida Amaral Zoilo Pires Camargo 《Mycopathologia》2010,169(1):37-46
The ecological niche or exact habitat of the fungus Paracoccidioides brasiliensis is not known, and few isolates have been obtained from the environment. In this study, ten isolates were analyzed with respect
to antigenic composition, serology, pathogenicity, and molecular aspects. Gp43 is considered to be the molecular basis for
the serodiagnosis of paracoccidioidomycosis; however, in this study only six of the environmental isolates secreted this molecule
(four in great amounts and two in small amounts). Other molecules were also produced. When exoantigens from these isolates
were tested using immunodiffusion, only four preparations were positive by ID tests. However, when these exoantigens were
tested by ELISA, all of them except one were able to detect anti-P. brasiliensis antibodies. In Western blot assays, these exoantigens showed different reactivities. Isolates that secreted gp43 presented
positive reactions for this molecule, and isolates that did not secrete gp43 gave positive reactions for other minor molecules.
RAPD analysis revealed that there is great genetic variation between these environmental isolates. These isolates were non-pathogenic:
no mortality was observed among the inoculated mice during an 18-month follow-up period. 相似文献
98.
Carlota Pascoal Sandra Brasil Rita Francisco Dorinda Marques-da-Silva Agnes Rafalko Jaak Jaeken Paula A. Videira Luísa Barros Vanessa dos Reis Ferreira 《Orphanet journal of rare diseases》2018,13(1):215
Background
Health-related Quality of Life (HrQoL) is a multidimensional measure, which has gained clinical and social relevance. Implementation of a patient-centred approach to both clinical research and care settings, has increased the recognition of patient and/or observer reported outcome measures (PROMs or ObsROMs) as informative and reliable tools for HrQoL assessment. Inherited Metabolic Diseases (IMDs) are a group of heterogeneous conditions with phenotypes ranging from mild to severe and mostly lacking effective therapies. Consequently, HrQoL evaluation is particularly relevant.Objectives
We aimed to: (1) identify patient and/or caregiver-reported HrQoL instruments used among IMDs; (2) identify the main results of the application of each HrQoL tool and (3) evaluate the main limitations of HrQoL instruments and study design/methodology in IMDs.Methods
A scoping review was conducted using methods outlined by Arksey and O’Malley. Additionally, we critically analysed each article to identify the HrQoL study drawbacks.Results
Of the 1954 studies identified, 131 addressed HrQoL of IMDs patients using PROMs and/or ObsROMs, both in observational or interventional studies. In total, we identified 32 HrQoL instruments destined to self- or proxy-completion; only 2% were disease-specific. Multiple tools (both generic and disease-specific) proved to be responsive to changes in HrQoL; the SF-36 and PedsQL questionnaires were the most frequently used in the adult and pediatric populations, respectively. Furthermore, proxy data often demonstrated to be a reliable approach complementing self-reported HrQoL scores. Nevertheless, numerous limitations were identified especially due to the rarity of these conditions.Conclusions
HrQoL is still not frequently assessed in IMDs. However, our results show successful examples of the use of patient-reported HrQoL instruments in this field. The importance of HrQoL measurement for clinical research and therapy development, incites to further research in HrQoL PROMs’ and ObsROMs’ creation and validation in IMDs.99.
M?nica Sawan Mendon?a Terezinha S Pera?olli Mário León Silva-Vergara Sílvio C Ribeiro Rafael Faria Oliveira Rinaldo Poncio Mendes Virmondes Rodrigues Jr 《Memórias do Instituto Oswaldo Cruz》2015,110(6):781-785
Paracoccidioidomycosis (PCM) is caused by dimorphic fungi fromtheParacoccidioides brasiliensis complex. Previous studies havedemonstrated that the severity of disease is associated with a T-helper 2 immuneresponse characterised by high interleukin (IL)-4 production. In the present study weanalysed two polymorphisms in the IL-4 gene (-590 C/T and intron-3microsatellite) in 76 patients with PCM and 73 control subjects from an endemic area.The production of IL-4 by peripheral blood mononuclear cells after antigen orphytohaemagglutinin stimulation was determined by ELISA. A significant correlationwas observed between the RP2/RP2 intron-3 genotype and infection withParacoccidioides sp. (p = 0.011), whereas the RP1/RP1 genotypewas correlated with resistance. No significant correlation was observed forthe IL-4 promoter polymorphism. Furthermore, the low IL-4expression observed in the control group compared with patients was associated withthe RP1/RP1 genotype. These results suggest that IL-4polymorphismsmight be associated with the ability of the host to control Paracoccidioidessp. infection. The relevance of this polymorphism is supported by theobservation that patients with disease produce high levels of IL-4 following mitogenor antigen stimulation. The IL-4 gene is located in the cytokinecluster region of chromosome 5 where other polymorphisms have also beendescribed. 相似文献
100.
Rosete Pescador Gilberto Barbante Kerbauy Wagner de Melo Ferreira Eduardo Purgatto Rogério Mamoru Suzuki Miguel Pedro Guerra 《Plant Growth Regulation》2012,68(1):67-76
Endogenous levels of IAA, ABA and four types of CKs were analyzed in zygotic and indirect (ISE) and direct somatic embryogenesis of Acca sellowiana. Zygotic and somatic embryos at different developmental stages were sampled for morphological and hormonal analysis. Both embryo types showed substantial asymmetry in hormone levels. Zygotic embryos displayed a conspicuous peak of IAA in early developmental stages. The results outlined the hormonal variations occurring during zygotic and somatic embryogenesis regarding the timing, nature and hormonal status involved in both processes. The short transient pulse of IAA observed on the 3rd day in culture was suggested to be involved with the signaling for the induction of somatic embryogenesis. Fertilized ovule development was associated with increased IAA levels 21?C24?days after pollination, followed by a sharp decrease in the cotyledonary stage, both in zygotic and somatic embryos. There was a prominent increase in ABA levels in cultures which generated ISE 24?C30?days after pollination, a period that corresponds to the heart and torpedo stages. The levels of total CKs (Z, [9R]Z, iP and [9R]iP) were also always higher in zygotic than in somatic embryogenesis. While zygotic embryogenesis was dominated by the presence of zeatin, the somatic process, contrarily, was characterized by a large variation of the other cytokinin forms and amounts studied. The above results, when taken together, could be related to the previously observed high frequency formation of anomalous somatic embryos formed in A. sellowiana, as well as to their low germination ability. 相似文献