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61.
62.
André Luis de Alcantara Guimarães Carlos Henrique Brasil Bizarri Leandro Silva Barbosa Marcos Jun Nakamura Mônica Freiman de Souza Ramos Ana Cláudia de Macêdo Vieira 《Flora》2013
Galls develop in different plant organs and are induced by the activity of various organisms. Some studies have investigated the ecological interactions between species of Clusia and gall-inducing insects. The goal of our study is to characterise changes in leaf anatomy caused by the activity of gall insects in Clusia lanceolata. Additionally, we also investigated the chemical composition of volatile compounds of normal leaves and those with galls to detect possible effects on the host plants. For anatomical studies, we used botanical material fixed in FAA50. Transversal sections of the leaf blade were obtained from samples of leaves located on the third and fourth nodes from both male and female individuals. Material was studied from both sexes both with unaffected leaves and leaves containing galls. Fresh leaves of C. lanceolata were used for the extraction of volatile compounds, which were submitted to stem distillation using a modified Clevenger apparatus determining the oil yields subsequently (w/w). The unaffected leaves of female and male individuals of C. lanceolata exhibit similar anatomical structures. However, galls on leaves of both sexes show anatomical differences. The activity of the gall insect Clusiamyia nitida induces several changes in the foliar anatomy and the distribution of metabolic compounds in new tissues during gall development. However, the larvae are not able to induce significant changes in the volatile compounds of inflected leaves from male and female individuals. 相似文献
63.
Mauro Leonelli Daniel O. Martins Luiz R. G. Britto 《Cellular and molecular neurobiology》2013,33(3):379-392
The activation of the transient receptor potential vanilloid type 1 channel (TRPV1) has been correlated with oxidative and nitrosative stress and cell death in the nervous system. Our previous results indicate that TRPV1 activation in the adult retina can lead to constitutive and inducible nitric oxide synthase-dependent protein nitration and apoptosis. In this report, we have investigated the potential effects of TRPV1 channel activation on nitric oxide synthase (NOS) expression and function, and the putative participation of ionotropic glutamate receptors in retinal TRPV1-induced protein nitration, lipid peroxidation, and DNA fragmentation. Intravitreal injections of the classical TRPV1 agonist capsaicin up-regulated the protein expression of the inducible and endothelial NOS isoforms. Using 4,5-diaminofluorescein diacetate for nitric oxide (NO) imaging, we found that capsaicin also increased the production of NO in retinal blood vessels. Processes and perikarya of TRPV1-expressing neurons in the inner nuclear layer of the retina were found in the vicinity of nNOS-positive neurons, but those two proteins did not colocalize. Retinal explants exposed to capsaicin presented high protein nitration, lipid peroxidation, and cell death, which were observed in the inner nuclear and plexiform layers and in ganglion cells. This effect was partially blocked by AP-5, a NMDA glutamate receptor antagonist, but not by CNQX, an AMPA/kainate receptor antagonist. These data support a potential role for TRPV1 channels in physiopathological retinal processes mediated by NO, which at least in part involve glutamate release. 相似文献
64.
Margarida Martins Jorge M. Pedrosa Maria J. Carvalho António Cabrita Rosário Oliveira 《Biofouling》2013,29(8):1015-1027
Biofilms are commonly associated with an increased risk of patient infection. In peritoneal dialysis (PD), catheter associated infection, especially peritonitis, remains a clinically relevant problem. Although the presence of a biofilm is recognized in relapsing, repeat, and catheter-related peritonitis, it remains poorly characterized. In this review, an update on the role of biofilms in PD infections is presented. The emerging concept that host cells and tissue associated biofilms, in addition to the biofilms on the catheters themselves, contribute to the recalcitrance of infections is discussed. Furthermore, the evidence of biofilms on PD catheters, their developmental stages, and the possible influence of the PD environment are reviewed. The focus is given to ex vivo and in vitro studies that contribute to the elucidation of the interplay between host, microbial, and dialysis factors. The key issues that are still to be answered and the challenges to clinical practice are discussed. 相似文献
65.
Diego Rodrigo Dolibaina Fernando Maia Silva Dias Olaf Hermann Hendrik Mielke Mirna Martins Casagrande 《Zoological Journal of the Linnean Society》2013,168(3):427-451
Three new species of Synargis Hübner, 1819, from Paraguay and southern and central Brazil are described: Synargis fandanga sp. nov. from Paraguay (Amambay and Paraguari) and southern Brazil (Paraná and Santa Catarina), Synargis rasqueada sp. nov. from central Brazil (Mato Grosso), and Synargis gorpa sp. nov. from southern Brazil (Paraná, Santa Catarina, and Rio Grande do Sul). Lectotypes are designated for Lemonias axenus Hewitson, 1876, Ematurgina axenus ochrophlegma Sitchel, 1911, Ematurgina acervata Seitz, 1932, and Ematurgina perrupta Seitz, 1932. Ematurgina ochrophlegma f. dissimilis Hayward, 1949, is a new synonym of Synargis bifasciata (Mengel, 1902), and Ematurgina ochrophlegma f. distincta Hayward, 1949, is a new synonym of Synargis axenus (Hewitson, 1876). The revalidation of E. perrupta Seitz, 1932, and the new status Synargis ochrophlegma (Stichel, 1911) are proposed. Ematurgina perrupta ab. roeberi Seitz, 1932, and Ematurgina bifasciata ochrophlegma ab. leucomelaina Breyer, 1930, are considered unavailable names. Based on a previous phylogenetic hypothesis, the phylogeny of the genus Synargis is reassessed, adding these new and revalidated taxa, and nine additional characters. The ‘Synargis regulus’ species group and the ‘Synargis axenus complex’ are recovered as monophyletic, with S. gorpa sp. nov. sister to the remaining species of the ‘S. axenus complex’. Additionally, an up‐to‐date geographical distribution map and a dichotomous key are provided, and the taxonomy of the taxa involved is discussed. © 2013 The Linnean Society of London 相似文献
66.
Hoffmannseggella viridiflora Verola & Semir (Laeliinae, Orchidaceae) is a recently discovered species in the campos rupestres vegetation of the Espinhaço Range, MG, Brazil, in synchronopatry with H. bradei (Pabst) V. P. Castro & Chiron. Both morphological and phenological studies indicate that these species are closely related. To substantiate the differentiation of these two species we examined their chromosome numbers and morphologies. The two species had different chromosome numbers, with H. bradei having 2n = 40 and H. viridiflora having 2n = 44 chromosomes, an aneuploid number not previously documented in the genus. Meiotic behavioral studies undertaken with H. bradei revealed many abnormalities related to bivalent numbers and chromosome migration, suggesting that meiotic abnormalities could generate aneuploid gametes and perhaps aneuploid zygotes. Karyotype formulas and chromosome morphologies are quite different between the species, so H. viridiflora was not directly derived from H. bradei through simple chromosome additions. Complementary analyses are necessary to understand the process and species involved in the origin of H. viridiflora. 相似文献
67.
Rosane Dias Costa Vanessa Amaral Mendon?a Frederico Marianetti Soriani Sandra Lyon Rachel Adriana Penido Ana Maria Duarte Dias Costa Marina Dias Costa Fabio de Souza Terra Mauro Martins Teixeira Carlos Mauricio de Figueiredo Antunes Antonio Lúcio Teixeira 《Memórias do Instituto Oswaldo Cruz》2013,108(8):1051-1056
Leprosy is an infectious and contagious spectral disease accompanied by a series of
immunological events triggered by the host response to the aetiologic agent,
Mycobacterium leprae . The induction and maintenance of the
immune/inflammatory response in leprosy are linked to multiple cell interactions and
soluble factors, primarily through the action of cytokines. The purpose of the
present study was to evaluate the serum levels of tumour necrosis factor (TNF)-α and
its soluble receptors (sTNF-R1 and sTNF-R2) in leprosy patients at different stages
of multidrug treatment (MDT) in comparison with non-infected individuals and to
determine their role as putative biomarkers of the severity of leprosy or the
treatment response. ELISA was used to measure the levels of these molecules in 30
healthy controls and 37 leprosy patients at the time of diagnosis and during and
after MDT. Our results showed increases in the serum levels of TNF-α and sTNF-R2 in
infected individuals in comparison with controls. The levels of TNF-α, but not
sTNF-R2, decreased with treatment. The current results corroborate previous reports
of elevated serum levels of TNF-α in leprosy and suggest a role for sTNF-R2 in the
control of this cytokine during MDT. 相似文献
68.
Marcos Paulo Wille Thaís Guimar?es Guilherme Henrique Campos Furtado Arnaldo Lopes Colombo 《Memórias do Instituto Oswaldo Cruz》2013,108(3):288-292
Candida species are an important cause of bloodstream infections (BSI). To evaluate the epidemiological, clinical and microbiological aspects of two cohorts {1994-1999 [period 1 (P1) ]; 2000-2004 [period 2 (P2) ]} of candidaemic patients, we performed a retrospective analysis from a laboratory-based survey. A total of 388 candidaemias were identified, with an incidence of 0.20/1,000 patient-days and a significant increase in P2 vs. P1 (0.25 vs. 0.15, p = 0.04). Cancer and prior antibiotic use were frequent and Candida albicans was the most prevalent species found (42.4%). Resistance to fluconazole was found in 2.47% of the strains. No differences were observed in the species distribution of Candida during the study periods. In the P2 cohort, there were higher prevalence of elderly individuals, cardiac, pulmonary and liver diseases, renal failure, central venous catheters and antibiotic therapy. In P1, there were higher prevalence of neurological diseases and chemotherapy. The crude mortality was 55.4%. In conclusion, our incidence rates remained high. Furthermore, the distribution pattern of Candida species and the fluconazole resistance profile remained unchanged. Moreover, we found a clear trend of higher prevalence of candidaemia among the elderly and among patients with comorbidities. Finally, it is necessary to discuss strategies for the prevention and control of Candida BSI in Brazil. 相似文献
69.
70.
Francisco Morinha Paulo Travassos Fernanda Seixas Ana Martins Rita Bastos Diogo Carvalho 《Bird Study》2013,60(2):255-259
Capsule The Skylark Alauda arvensis had the highest overall mortality in ten Northern Portuguese wind farms surveyed between 2006 and 2011. Analysis from the integration of conventional and molecular techniques suggest a sex and age biased mortality affecting mainly adult males (90.9%), which may be related to their characteristic breeding male song-flights making them highly vulnerable to collision with wind turbines. The results highlight the added value of more complete population impact assessments that go beyond simple carcass identification at wind farms. 相似文献