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111.
da Silva AE Rados PV da Silva Lauxen I Gedoz L Villarinho EA Fontanella V 《Mutation research》2007,632(1-2):121-125
This study aimed to investigate the effect of radiation from panoramic radiographs on the cells of the lateral border of the tongue by evaluating nuclear changes. Forty-two patients were included: 22 had one radiograph (Group I), and 20 required a repeat radiograph due to error in the first exposure (Group II). Material for the cytopathologic evaluation was collected before radiographs and 10 days later. Smears were stained with the Feulgen reaction and micronuclei, buds, broken eggs, karyorrhexis and binucleate cells were scored. The comparison of nuclear changes before and after radiation exposure in both groups revealed a statistically higher number of broken eggs, buds, karyorrhexis and binucleate cells 10 days after exposure (P=0.01). The number of karyorrhexis and binucleate cells was greater in group II (P=0.01). There was no change in the frequency of micronuclei before and after the radiographs. Radiation emitted during panoramic radiographs increased the number of nuclear anomalies (except micronuclei) in exfoliated cells of the lateral border of the tongue. This effect was more pronounced when the patients were exposed to a repeat radiograph, without however implying increased risk of irreversible tissue damage. 相似文献
112.
Kimberley E. Wever Carlijn R. Hooijmans Niels P. Riksen Thomas B. Sterenborg Emily S. Sena Merel Ritskes-Hoitinga Michiel C. Warlé 《PloS one》2015,10(11)
Background
Ischemic preconditioning (IPC) of the heart is a protective strategy in which a brief ischemic stimulus immediately before a lethal ischemic episode potently limits infarct size. Although very promising in animal models of myocardial infarction, IPC has not yet been successfully translated to benefit for patients.Objective
To appraise all preclinical evidence on IPC for myocardial infarction and identify factors hampering translation.Methods and results
Using systematic review and meta-analysis, we identified 503 animal studies reporting infarct size data from 785 comparisons between IPC-treated and control animals. Overall, IPC reduced myocardial infarction by 24.6% [95%CI 23.5, 25.6]. Subgroup analysis showed that IPC efficacy was reduced in comorbid animals and non-rodents. Efficacy was highest in studies using 2–3 IPC cycles applied <45 minutes before myocardial infarction. Local and remote IPC were equally effective. Reporting of study quality indicators was low: randomization, blinding and a sample size calculation were reported in 49%, 11% and 2% of publications, respectively.Conclusions
Translation of IPC to the clinical setting may be hampered by the observed differences between the animals used in preclinical IPC studies and the patient population, regarding comorbidity, sex and age. Furthermore, the IPC protocols currently used in clinical trials could be optimized in terms of timing and the number of ischemic cycles applied. In order to inform future clinical trials successfully, future preclinical studies on IPC should aim to maximize both internal and external validity, since poor methodological quality may limit the value of the preclinical evidence. 相似文献113.
Isadora F. G. Sena Isabella T. Borges Luiza Lousado Patrick O. Azevedo Julia P. Andreotti Viviani M. Almeida 《Cell cycle (Georgetown, Tex.)》2017,16(21):2018-2022
Bone marrow fibrosis is a reactive process, and a central pathological feature of primary myelofibrosis. Revealing the origin of fibroblastic cells in the bone marrow is crucial, as these cells are considered an ideal, and essential target for anti-fibrotic therapy. In 2 recent studies, Decker et al. (2017) and Schneider et al. (2017), by using state-of-the-art techniques including in vivo lineage-tracing, provide evidence that leptin receptor (LepR)-expressing and Gli1-expressing cells are responsible for fibrotic tissue deposition in the bone marrow. However, what is the relationship between these 2 bone marrow cell populations, and what are their relative contributions to bone marrow fibrosis remain unclear. From a drug development perspective, these works bring new cellular targets for bone marrow fibrosis. 相似文献
114.
Stephen F. Ferrari Leonardo Sena Maria Paula C. Schneider José S. Silva Júnior 《International journal of primatology》2010,31(5):693-714
We describe Rondon’s marmoset (Mico rondoni sp. n.) from the Rio Jamari in the Brazilian state of Rondônia and differentiate the species from other Amazonian marmosets on the basis of morphological, genetic, and zoogeographic characteristics. Mico rondoni sp. n. is a typical bare-eared marmoset of predominantly grayish coloration and unpigmented face and cheiridia, which contrasts clearly with its more brownish and pigmented parapatric congeners Mico melanurus and M. nigriceps. Genetically, the new species is unquestionably distinct from Mico emiliae, with which it had been synonimized previously. The geographic range of the new species is defined as the area delimited by the Mamoré, Madeira, and Jiparaná rivers to the west, north, and east, respectively, and the Serra dos Pacaás Novos, to the south, where it is substituted by Mico melanurus. Depending on its exact limits, this range may cover an area of little more than 100,000 km2. A characteristic of the ecology of Mico rondoni sp. n. is its range-wide sympatry with the similarly sized tamarin Saguinus fuscicollis weddelli, which may be a key factor determining the rarity or absence of the new species from many areas within its geographic range. Its apparent scarcity may make the new species exceptionally vulnerable to the effects of the intense human colonization occurring throughout much of its known range, and provoke cause for concern for its long-term survival. 相似文献
115.
Maria T.A. Oliveira Alexandre M.R. Teixeira Cícera J.M. Cassiano Diniz M. Sena Jr. Henrique D.M. Coutinho Irwin R.A. Menezes Fernando G. Figueredo Luiz E. Silva Thiago A. Toledo Ricardo R.F. Bento 《Saudi Journal of Biological Sciences》2016,23(1):34-38
The compound 4-(Phenylsulfonyl) morpholine belongs to the class of sulfonamides, which are widely used in the treatment of a large number of diseases caused by microorganisms. This compound has a morpholine group, which is also known for its antimicrobial properties. The aim of the present study was to investigate the antimicrobial and modulating activity of 4-(Phenylsulfonyl) morpholine against standard and multi-resistant strains of Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and strains of the fungi Candida albicans, C. tropicalis and C. krusei. Antimicrobial activity was assessed based on the minimum inhibitory concentration (MIC) using the microdilution method. MIC was ⩾1024 μg/mL for all microorganisms. Regarding modulating activity, the most representative effect occurred with the combination of 4-(Phenylsulfonyl) morpholine at a concentration of 128 μg/mL (MIC 1/8) and amikacin against P. aeruginosa 03, with a reduction in MIC from 312.5 to 39.06 μg/mL. 相似文献
116.
117.
Steno L. Oliveira Marcelo S. da Silva Josean F. Tavares José G. Sena‐Filho Hellane F. S. Lucena Marco A. V. Romero José M. Barbosa‐Filho 《化学与生物多样性》2010,7(2):302-326
Erythroxylum, the most representative genus of the Erythroxylaceae family, presents tropane alkaloids as main constituents. This class of compounds greatly contributes to the chemotaxonomic characterization of plants of this genus, and it has important medical uses and shows toxic effects. This review describes 186 tropane alkaloids in the 35 species of Erythroxylum distributed worldwide. In addition, a compilation of their 13C‐NMR spectral data is presented. 相似文献
118.
Rogério Mercês Ferreira Santos Stela Dalva Vieira Midlej Silva Kaleandra Sena Fabienne Micheli Karina Peres Gramacho 《Tropical plant biology》2013,6(1):37-45
Theobroma cacao L., the chocolate tree, is an important tropical tree-crop that provides sustainable economic and environmental benefits to some of the poorest and most ecologically sensitive areas of the world. Ceratocystis wilt (CW), caused by the fungus Ceratocystis cacaofunesta, is a highly dangerous disease capable of killing the cacao plant. Histopathological studies of the host–pathogen interaction are an effective resource to study pathogenesis which will ultimately lead to a better elucidation of the mechanisms of host resistance. We analyzed the development of C. cacaofunesta reproductive structures, the pattern of fungal colonization and the anatomical responses of cacao resistant (TSH 1188) and susceptible (CCN 51) genotypes to CW. Results showed that conidia germination started within 4 h after inoculation (hai) in agar, by 12 hai conidia germination was 80 %. The resistant genotype showed little or no fungal colonization compared to the susceptible genotype. Host reactions were characterized by greater quantities of gels, gums and tyloses in the susceptible genotypes compared to the resistant. The susceptible genotype had a large number of cells surrounding the xylem vessels that were infused with dark brown phenolic compounds. The host defense reaction observed near the xylem in the resistant genotype, suggest that a mechanism involved with resistance to C. cacaofunesta. 相似文献
119.
U. Asanka D. Jayasinghe Upali S. Amarasinghe Sena S. De Silva 《International Review of Hydrobiology》2005,90(2):209-222
The aim of this study was to check the suitability of some trophic models developed for temperate regions to classify the non‐perennial reservoirs of Sri Lanka in order to manage culture‐based fisheries of those reservoirs. A limnological study was carried out in 45 non‐perennial reservoirs, which have been randomly selected for stocking of fish fingerlings for the development of culture‐based fisheries. High total phosphorous (TP) content in relation to algal biomass indicates high non‐algal turbidity in all reservoirs. Carlson's trophic state indices (TSI) measured on the basis of Secchi disc depth [TSI (SDD)], TP [TSI (TP)] and chlorophyll a [TSI (Chl‐a)] show that the 45 reservoirs studied are characterized by TSI (TP) = TSI (SDD) > TSI (Chl‐a), indicating that non‐algal particulate matter or colour dominates underwater light attenuation. As TSI (Chl‐a) is positively correlated to culture‐based fisheries yield, it is useful for planning culture‐based fisheries development strategies in non‐perennial reservoirs of Sri Lanka, and has the potential to be used elsewhere in the tropics for comparable developments. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
120.
Mariana Valéria de Araújo Sena Thiago da Silva Marinho Felipe Chinaglia Montefeltro Max Cardoso Langer Thiago Schineider Fachini William Roberto Nava André Eduardo Piacentini Pinheiro Esaú Victor de Araújo Paul Aubier Rafael César Lima Pedroso de Andrade Juliana Manso Sayão Gustavo Ribeiro de Oliveira Jorge Cubo 《Journal of morphology》2023,284(1):e21536
Osteoderms are mineralized structures embedded in the dermis, known for nonavian archosaurs, squamates, xenarthrans, and amphibians. Herein, we compared the osteoderm histology of Brazilian Notosuchia of Cretaceous age using three neosuchians for comparative purposes. Microanatomical analyses showed that most of them present a diploe structure similar to those of other pseudosuchians, lizards, and turtles. This structure contains two cortices (the external cortex composed of an outer and an inner layers, and the basal cortex) and a core in-between them. Notosuchian osteoderms show high bone compactness (>0.85) with varying degrees of cancellous bone in the core. The neosuchian Guarinisuchus shows the lowest bone compactness with a well-developed cancellous layer. From an ontogenetic perspective, most tissues are formed through periosteal ossification, although the mineralized tissues observed in baurusuchid LPRP/USP 0634 suggest a late metaplastic development. Histology suggests that the ossification center of notosuchian osteoderm is located at the keel. Interestingly, we identified Sharpey's fibers running perpendicularly to the outer layer of the external cortex in Armadillosuchus arrudai, Itasuchus jesuinoi, and Baurusuchidae (LPRP/USP 0642). This feature indicates a tight attachment within the dermis, and it is evidence for the presence of an overlying thick leathery layer of skin over these osteoderms. These data allow a better understanding of the osteohistological structure of crocodylomorph dermal bones, and highlight their structural diversity. We suggest that the vascular canals present in some sampled osteoderms connecting the inner layer of the external cortex and the core with the external surface may increase osteoderm surface and the capacity of heat transfer in terrestrial notosuchians. 相似文献