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451.
Manoel Batista da Silva Júnior Edson A. Pozza Mário L. V. Resende Pedro M. R. Júnior Bruno H. G. Costa Camila A. Carvalho Alexandre R. M. Resende Deila Magna dos Santos Botelho 《Journal of Phytopathology》2018,166(10):686-693
The growing demand for alternative strategies for plant disease management has sought a reduction in the use of fungicides via the employment of resistance inducers and foliar fertilizers, among others. Therefore, this study aimed at evaluating the following foliar fertilizers for the management of phoma leaf spot: a foliar fertilizer based on macro‐ and micronutrients (Fmm: 10% N, 4% S, B, 5% Fe and 5% Zn); one based on cobalt and molybdenum (Fcm: 2% Co and 3% Mo); manganese phosphite (FMn: 30% P2O5 and 9% Mn); and the FMn+Fmm, Fcm+Fmm and FMn+Fcm+Fmm associations compared to a boscalid fungicide and a control with no treatment. The disease severity, the chlorophyll a and b contents, the net photosynthetic rate (LPR), the phenylalanine ammonia lyase (PAL) activity and the lignin content in leaves were assessment. Based on the severity, the area under the disease severity progress curve (AUSPC) and the efficiency of disease control in relation to untreated plants were calculated. The experimental design was in randomized blocks with eight treatments and three replications. Treatments FMn+Fmm and Fcm were the most effective in reducing the AUPSC in comparison with the control and promoted an increased activity of PAL. FMn was the treatment that promoted the highest increase in the LPR. There were no effects of the treatments on the lignin content compared to the control. 相似文献
452.
Laura Siracusa Edoardo Napoli Teresa Tuttolomondo Mario Licata Salvatore LaBella Maria Cristina Gennaro Claudio Leto Mauro Sarno Elisa Sperlinga Giuseppe Ruberto 《化学与生物多样性》2019,16(3)
A collection of nine Myrtus communis samples from different localities of Sicily was evaluated. Morphological traits and production characteristics have been chosen as parameters to arrange the samples into homogeneous groups and to identify the best biotypes for possible future agro‐industrial exploitation. The plant material has been subjected to taxonomic characterization from biometric and phytochemical perspectives. Myrtle berries and leaves have been analyzed for their content in metabolites, applying a cascade extraction protocol for M. communis leaves and a single hydroalcoholic extraction for berries, whereas hydrodistillation procedures have been applied to obtain the essential oils from berries and leaves. The analyses of non‐volatile components were carried out by LC‐UV‐DAD‐ESI‐MS. All the extracts were characterized by the presence of numerous polyphenols, namely highly hydroxylated flavonols such as quercetin and myricetin; and ellagic acid detected in all samples. In addition, myrtle berries contained nine different anthocyanins, namely delphinidin, petunidin, cyanidin and malvidin derivatives. The essential oils (EOs) were analyzed by a combination of GC‐FID and GC/MS. A total of 33 and 34 components were fully characterized with the predominance of α‐pinene, myrtenyl acetate, linalool, 1,8‐cineole and linalyl acetate. All phytochemical profiles were subjected to cluster analyses, which allowed subdividing the myrtle samples in different chemical groups. 相似文献
453.
Gabriela Rodríguez-Arellanes Carolina Nascimento de Sousa Mauro de Medeiros-Muniz José A. Ramírez Cláudia V. Pizzini Marcos de Abreu-Almeida Manoel M. Evangelista de Oliveira Ana-Marisa Fusco-Almeida Tania Vite-Garín Nayla S. Pitangui Daniel A. Estrada-Bárcenas Antonio E. González-González María José Soares Mendes-Giannini Rosely M. Zancopé-Oliveira Maria-Lucia Taylor 《Eukaryotic cell》2013,12(7):1033-1038
The MAT1-1 and MAT1-2 idiomorphs associated with the MAT1 locus of Histoplasma capsulatum were identified by PCR. A total of 28 fungal isolates, 6 isolates from human clinical samples and 22 isolates from environmental (infected bat and contaminated soil) samples, were studied. Among the 14 isolates from Mexico, 71.4% (95% confidence interval [95% CI], 48.3% to 94.5%) were of the MAT1-2 genotype, whereas 100% of the isolates from Brazil were of the MAT1-1 genotype. Each MAT1 idiomorphic region was sequenced and aligned, using the sequences of the G-217B (+ mating type) and G-186AR (− mating type) strains as references. BLASTn analyses of the MAT1-1 and MAT1-2 sequences studied correlated with their respective + and − mating type genotypes. Trees were generated by the maximum likelihood (ML) method to search for similarity among isolates of each MAT1 idiomorph. All MAT1-1 isolates originated from Brazilian bats formed a well-defined group; three isolates from Mexico, the G-217B strain, and a subgroup encompassing all soil-derived isolates and two clinical isolates from Brazil formed a second group; last, one isolate (EH-696P) from a migratory bat captured in Mexico formed a third group of the MAT1-1 genotype. The MAT1-2 idiomorph formed two groups, one of which included two H. capsulatum isolates from infected bats that were closely related to the G-186AR strain. The other group was formed by two human isolates and six isolates from infected bats. Concatenated ML trees, with internal transcribed spacer 1 (ITS1) -5.8S-ITS2 and MAT1-1 or MAT1-2 sequences, support the relatedness of MAT1-1 or MAT1-2 isolates. H. capsulatum mating types were associated with the geographical origin of the isolates, and all isolates from Brazil correlated with their environmental sources. 相似文献
454.
Teotónio H Manoel D Phillips PC 《Evolution; international journal of organic evolution》2006,60(6):1300-1305
The evolution of breeding systems results from the existence of genetic variation and selective forces favoring different outcrossing rates. In this study we determine the extent of genetic variation for characters directly related to outcrossing, such as male frequency, male mating ability, and male reproductive success, in several wild isolates of the nematode Caenorhabditis elegans. This species is characterized by an androdioecious breeding system in which males occur with hermaphrodites that can either self-fertilize or outcross with males. We find genetic variation for all characters measured, but also find that environmental variation is a large fraction of the total phenotypic variance. We further determine the existence of substantial genetic variation for population competitive performance in several laboratory environments. However, these measures are uncorrelated with outcrossing characters. The data presented here contribute to an understanding of male maintenance in natural populations through their role in outcrossing. 相似文献
455.
Andre Tsin Chih Chen Fabio Payo Aline Lopes Chagas Regiane Saraiva De Souza Melo Alencar Claudia Megumi Tani Karina Gondim Moutinho da Conceio Vasconcelos Manoel de Souza Rocha Heloisa de Andrade Carvalho Paulo Marcelo Gehm Hoff Flair Jos Carrilho 《Reports of Practical Oncology and Radiotherapy》2021,26(2):226
456.
Piet K Vanhoenacker Isabel Decramer Olivier Bladt Giovanna Sarno Charlotte Bevernage William Wijns 《BMC cardiovascular disorders》2007,7(1):1-11
Background
Post thrombotic syndrome (PTS) is a burdensome and costly complication of deep venous thrombosis (DVT) that develops in 20–40% of patients within 1–2 years after symptomatic DVT. Affected patients have chronic leg pain and swelling and may develop ulcers. Venous valve disruption from the thrombus itself or thrombus-associated mediators of inflammation is considered to be a key initiating event for the development of venous hypertension that often underlies PTS. As existing treatments for PTS are extremely limited, strategies that focus on preventing the development of PTS in patients with DVT are more likely to be effective and cost-effective in reducing its burden. Elastic compression stockings (ECS) could be helpful in preventing PTS; however, data on their effectiveness are scarce and conflicting.Methods/Design
The SOX Trial is a randomized, allocation concealed, double-blind multicenter clinical trial. The objective of the study is to evaluate ECS to prevent PTS. A total of 800 patients with proximal DVT will be randomized to one of 2 treatment groups: ECS or placebo (inactive) stockings worn on the DVT-affected leg daily for 2 years. The primary outcome is the incidence of PTS during follow-up. Secondary outcomes are severity of PTS, venous thromboembolism (VTE) recurrence, death from VTE, quality of life and cost-effectiveness. Outcomes will be evaluated during 6 clinic visits and 2 telephone follow ups. At baseline, 1 and 6 months, blood samples will be obtained to evaluate the role of inflammatory mediators and genetic markers of thrombophilia in the development of PTS (Bio-SOX substudy).Discussion
The SOX Trial will be the largest study and the first with a placebo control to evaluate the effectiveness of ECS to prevent PTS. It is designed to provide definitive data on the effects of ECS on the occurrence and severity of PTS, as well as DVT recurrence, cost-effectiveness and quality of life. This study will also prospectively evaluate the predictive role of biomarkers that are reflective of putative underlying pathophysiological mechanisms in the development of clinical PTS. As such, our results will impact directly on the care of patients with DVT.Trial Registration
NCT00143598 and ISRCTN71334751 相似文献457.
Castro SV de Carvalho AA da Silva CM Faustino LR Campello CC Lucci CM Báo SN de Figueiredo JR Rodrigues AP 《Cell and tissue research》2011,346(2):283-292
Goat ovarian cortex fragments were subjected to slow freezing in the presence of various solutions containing intracellular
cryoprotectants, including 1.0 M ethylene glycol (EG), propanediol (PROH), or dimethyl sulfoxide (DMSO), with or without sucrose
and/or fetal calf serum (FCS). Histological examination revealed that only the DMSO-containing solutions were able to maintain
a follicular ultrastructure similar to the morphology observed in the fresh control. Therefore, fragments previously cryopreserved
in DMSO solutions (with and without sucrose and/or FCS) were cultured in vitro for 48 h and then subjected to viability, histological,
and ultrastructural analysis. No significant differences were observed among the percentages of morphologically normal follicles
in cryopreserved ovarian tissue before in vitro culture (DMSO: 62.5%; DMSO + sucrose: 68.3%; DMSO + FCS: 60.0%; DMSO + sucrose + FCS:
60.0%) and after culture (DMSO: 60.8%; DMSO + sucrose: 64.2%; DMSO + FCS: 70.8%; DMSO + sucrose + FCS: 55.0%). Following in
vitro culture, the viability analysis showed that only the freezing solution containing DMSO and FCS (75.6%) maintained a
percentage of viable follicles similar to that observed after culture without cryopreservation (89.3%). As determined by ultrastructural
analysis, morphologically normal preantral follicles were detected in the fresh control and in fragments cultured before and
after cryopreservation with DMSO and FCS. Thus, a freezing solution containing DMSO and FCS, under the experimental conditions
tested here, guaranteed the maintenance of viability and follicular ultrastructure after short-term in vitro culture. 相似文献
458.
Morphological and genetic diversity of Beaufort Sea diatoms with high contributions from the Chaetoceros neogracilis species complex 下载免费PDF全文
Sergio Balzano Isabella Percopo Raffaele Siano Priscillia Gourvil Mélanie Chanoine Dominique Marie Daniel Vaulot Diana Sarno 《Journal of phycology》2017,53(1):161-187
Seventy‐five diatom strains isolated from the Beaufort Sea (Canadian Arctic) in the summer of 2009 were characterized by light and electron microscopy (SEM and TEM), as well as 18S and 28S rRNA gene sequencing. These strains group into 20 genotypes and 17 morphotypes and are affiliated with the genera Arcocellulus, Attheya, Chaetoceros, Cylindrotheca, Eucampia, Nitzschia, Porosira, Pseudo‐nitzschia, Shionodiscus, Thalassiosira, and Synedropsis. Most of the species have a distribution confined to the northern/polar area. Chaetoceros neogracilis and Chaetoceros gelidus were the most represented taxa. Strains of C. neogracilis were morphologically similar and shared identical 18S rRNA gene sequences, but belonged to four distinct genetic clades based on 28S rRNA, ITS‐1 and ITS‐2 phylogenies. Secondary structure prediction revealed that these four clades differ in hemi‐compensatory base changes (HCBCs) in paired positions of the ITS‐2, suggesting their inability to interbreed. Reproductively isolated C. neogracilis genotypes can thus co‐occur in summer phytoplankton communities in the Beaufort Sea. C. neogracilis generally occurred as single cells but also formed short colonies. It is phylogenetically distinct from an Antarctic species, erroneously identified in some previous studies as C. neogracilis, but named here as Chaetoceros sp. This work provides taxonomically validated sequences for 20 Arctic diatom taxa, which will facilitate future metabarcoding studies on phytoplankton in this region. 相似文献
459.
Jo?o B. A. Neto Cecília R. da Silva Maria A. S. Neta Rosana S. Campos Janaína T. Siebra Rose A. C. Silva Danielle M. Gaspar Hemerson I. F. Magalh?es Manoel O. de Moraes Marina D. P. Lobo Thalles B. Grangeiro Tatiane S. C. Carvalho Emilay B. T. Diogo Eufranio N. da Silva Júnior Felipe A. R. Rodrigues Bruno C. Cavalcanti Hélio V. N. Júnior 《PloS one》2014,9(5)
In recent decades, the incidence of candidemia in tertiary hospitals worldwide has substantially increased. These infections are a major cause of morbidity and mortality; in addition, they prolong hospital stays and raise the costs associated with treatment. Studies have reported a significant increase in infections by non-albicans Candida species, especially C. tropicalis. The number of antifungal drugs on the market is small in comparison to the number of antibacterial agents available. The limited number of treatment options, coupled with the increasing frequency of cross-resistance, makes it necessary to develop new therapeutic strategies. The objective of this study was to evaluate and compare the antifungal activities of three semisynthetic naphthofuranquinone molecules against fluconazole-resistant Candida spp. strains. These results allowed to us to evaluate the antifungal effects of three naphthofuranquinones on fluconazole-resistant C. tropicalis. The toxicity of these compounds was manifested as increased intracellular ROS, which resulted in membrane damage and changes in cell size/granularity, mitochondrial membrane depolarization, and DNA damage (including oxidation and strand breakage). In conclusion, the tested naphthofuranquinones (compounds 1–3) exhibited in vitro cytotoxicity against fluconazole-resistant Candida spp. strains. 相似文献
460.
Spencer JS Dockrell HM Kim HJ Marques MA Williams DL Martins MV Martins ML Lima MC Sarno EN Pereira GM Matos H Fonseca LS Sampaio EP Ottenhoff TH Geluk A Cho SN Stoker NG Cole ST Brennan PJ Pessolani MC 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(12):7930-7938
Diagnosis of leprosy is a major obstacle to disease control and has been compromised in the past due to the lack of specific reagents. We have used comparative genome analysis to identify genes that are specific to Mycobacterium leprae and tested both recombinant proteins and synthetic peptides from a subset of these for immunological reactivity. Four unique recombinant proteins (ML0008, ML0126, ML1057, and ML2567) and a panel of 58 peptides (15 and 9 mer) were tested for IFN-gamma responses in PBMC from leprosy patients and contacts, tuberculosis patients, and endemic and nonendemic controls. The responses to the four recombinant proteins gave higher levels of IFN-gamma production, but less specificity, than the peptides. Thirty-five peptides showed IFN-gamma responses only in the paucibacillary leprosy and household contact groups, with no responses in the tuberculosis or endemic control groups. High frequencies of IFN-gamma-producing CD4+ and CD8+ T cells specific for the 15- and 9-mer peptides were observed in the blood of a paucibacillary leprosy patient. 9-mer peptides preferentially activated CD8+ T cells, while the 15-mer peptides were efficient in inducing responses in both the CD4+ and CD8+ T cell subsets. Four of the six 9-mer peptides tested showed promising specificity, indicating that CD8+ T cell epitopes may also have diagnostic potential. Those peptides that provide specific responses in leprosy patients from an endemic setting could potentially be developed into a rapid diagnostic test for the early detection of M. leprae infection and epidemiological surveys of the incidence of leprosy, of which little is known. 相似文献