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51.
Biology Bulletin - This study investigated the protective effects of quercetin (QUE) in doxorubicin (DOX)-induced testicular toxicity in rats. In the present study, testicular histomorphometry, the... 相似文献
52.
Marciane Danniela Fleck Ervandil Corrêa Costa Maristela Machado Araujo Karine Schoeninger Leonardo Mortari Machado Jéssica Maus da Silva Leandra Pedron Dayanna do Nascimento Machado Jardel Boscardin 《Revista Brasileira de Entomologia》2019,63(3):212-216
Forest species can have their seeds damaged by granivorous insects, especially by those in their larval stage. In this context, this study aims to report the occurrence of Amblycerus species in Cordia trichotoma seeds, to describe their main damage to seeds and effects on germination, as well as their associated hymenopteran parasitoids. Therefore, seven trees were selected in the municipality of Taquaruçu do Sul, RS, Brazil. Fruits were collected weekly from the medium third of the tree crown, from the beginning of their formation until total dehiscence. To examine the damage caused by granivorous insects within the fruits, 15 fruits from each tree were sectioned with a scalpel. Furthermore, 10 fruits from each tree were stored individually in clear plates to verify the occurrence and identification of granivorous insect species. Evidence of the damage caused to seeds was verified through the germination test by comparing preserved and damaged seeds, with four repetitions of 25 seeds each. The species Amblycerus longesuturalis and Amblycerus profaupar (Chrysomelidae: Bruchinae) were found associated with fruits of C. trichotoma. Female insects predominantly laid eggs on the superior part between the marcescent calyx and the fruit, and larvae perforated the fruit tegument to start consuming seed embryos and reserves. Bruquine larvae are parasitized by Hymenoptera of Bracon, Mirax, Omeganastatus and Triapsis genera. In conclusion, the germination of C. trichotoma seeds is significantly affected by emergence orifices caused by granivorous species. 相似文献
53.
Carlos Henrique de Vasconcelos Nascimento Rafael Pereira-Silva Iris Gabrielly Arruda dos Santos Gilberto Gonçalves Rodrigues 《水生昆虫》2019,40(2):146-172
New records and distributional notes of Chironomidae (Insecta, Diptera) are provided for four protected areas in the state of Pernambuco, northeastern Brazil. Additionally, we also present new records and update of distributional ranges from Brazil and the Neotropical Region. In total, 810 specimens belonging to 35 genera within the subfamilies Chironominae (22 taxa), Tanypodinae (11 taxa) and Orthocladiinae (2 taxa) were found. The subfamilies Chironominae and Tanypodinae predominated. Axarus Roback, 1980 and the Tanytarsus ortoni-group were recorded for the first time in the state of Pernambuco, while Nanocladius Kieffer, 1913a was recorded for the first time in the Northeast Region of Brazil. Our results make evident how much and where current knowledge of the northeastern Brazil chironomids remains fragmentary. 相似文献
54.
de Oliveira Hellen Oliveira de Castro Gledson Luiz Salgado Correa Lorena Oliveira Silvestre Walter Vellasco Duarte do Nascimento Sidney Vasconcelos da Silva Valadares Rafael Borges de Oliveira Guilherme Corrêa Santos Rodolfo Inacio Nunes Festucci-Buselli Reginaldo Alves Pinheiro Hugo Alves 《Photosynthesis research》2019,140(2):189-205
Photosynthesis Research - This study examined whether drought sensitivity in açaí (Euterpe oleracea Mart.) is associated with reductions in photosynthesis and increasing oxidative stress... 相似文献
55.
Young Seung Lee Jae‐Young Chung Sang Bong Jeon Ae‐Kyoung Lee Hyung‐Do Choi 《Bioelectromagnetics》2019,40(7):445-457
This paper proposes a novel in vitro exposure system operating at millimeter‐wave (mmWave) 28 GHz, one of the frequency bands under consideration for fifth generation (5G) communication. We employed the field uniformity concept along cross‐sectional observation planes at shorter distances from the radiation antenna for better efficiency and a small‐size system. A choke‐ring antenna was designed for this purpose in consideration of a wider beamwidth (BW) and a symmetric far‐field pattern across three principal planes. The permittivity of Dulbecco's modified Eagle's medium solution was measured to examine the specific absorption rate (SAR) of the skin cell layer inside a Petri dish model for a three‐dimensional (3D) cell culture in vitro experiment. The best deployment of Petri dishes, taking into account a geometrical field symmetry, was proposed. Local SAR values within the cell layer among the Petri dishes were determined with different polarization angles. It was determined that this polarization effect should be considered when the actual exposure and deployment were conducted. We finally proposed an in vitro exposure system based on the field uniformity including downward exposure from an antenna for 3D cell culture experiments. A small‐size chamber system was obtained, and the size was estimated using the planar near‐field chamber design rule. Bioelectromagnetics. 2019;40:445–457. © 2019 Bioelectromagnetics Society 相似文献
56.
Cristina S. Freire-Nordi Armando A. H. Vieira Otaciro R. Nascimento 《Journal of phycology》1998,34(4):631-637
The aim of this work was to investigate the role of the polysaccharide sheath of the microalga Spondylosium panduriforme (Chlorophyceae, Desmidiaceae) in the selective permeability and transport of molecules into the interior of the cell. We have used the electron paramagnetic resonance (EPR) technique applied to a variety of spin labels of a hydrophobic nature with different substitutents on the ring (−OH, =O, −N=C=S, −NH3 + , and others). The spin label EPR signals were destroyed as a consequence of metabolic processes once the spin probes had entered the cells. The decay time of the EPR signal was regulated by the diffusion mechanism across the polysaccharide sheath, cell wall, and membrane. To discriminate the effect of the polysaccharide sheath from that of the cell wall and membrane, the polysaccharide sheath was removed by ultrasonic treatment. The decay times for the cells without capsule were faster than those for intact cells, and a possible mechanism of interaction involving hydrogen bonds between the spin labels and the −OH groups of the polysaccharide sheath is presented. These were expressed by their diffusion and friction coefficients as derived from Ficks' Second Law and the Einstein-Stokes equation and were summarized in terms of diffusion coefficients ( D 1 ) for the capsule medium in the order: =O < −OH < −phe < −H < −N=C=S; and for cell wall and membrane ( D 2 ): −OH < −H < =O < −NH3 + ≅−phe < −N=C=S. For the friction coefficients ( f 1 and f 2 ), the order was inverted. These results suggest the capsule plays a role in selectivity as a result of polar interactions with the spin labels. 相似文献
57.
58.
Nascimento M Abourjeily N Ghosh A Zhang WW Matlashewski G 《Molecular microbiology》2003,50(5):1517-1526
Leishmania is a protozoan pathogen which is transmitted to humans through the bite of an infected sandfly. This infection results in a spectrum of diseases throughout the developing world, collectively known as leishmaniasis. During its life cycle, Leishmania differentiates from the promastigote stage in the sandfly vector into the amastigote stage in the mammalian host where it multiplies exclusively in macrophage phagolysosomes. Although differentiation of Leishmania is essential for its survival and pathogenesis in the mammalian host, this process is poorly understood. In higher eukaryotic cells, protein tyrosine phosphorylation plays a central role in cell proliferation, differentiation and overall function. We have therefore investigated the role of protein tyrosine phosphorylation in Leishmania differentiation by undertaking complementary approaches to mediate protein tyrosine dephosphorylation in vivo. In the present study, L. donovani were engineered to express a mammalian protein tyrosine phosphatase, or were treated with inhibitors of protein tyrosine kinases, and the resulting phenotype was examined. Both approaches resulted in a partial differentiation from promastigotes to amastigotes including the expression of the amastigote specific A2 protein, morphological change and increased virulence. These data provide support for the involvement of tyrosine phosphorylation in the differentiation of Leishmania. 相似文献
59.
60.
C S Hong Y G Kwak J H Ji S W Chae Do H Kim 《Biochemical and biophysical research communications》2001,289(4):882-887
Junctate is a newly identified integral ER/SR membrane calcium binding protein, which is an alternative splicing form of the same gene generating aspartyl beta-hydroxylase and junctin. Screening a mouse heart cDNA library using canine junctin cDNA as a probe yielded three complete mouse heart cDNAs. One of the cDNAs is homologous to the previously reported human junctate. The three mouse junctate proteins are composed of 270, 259, and 215 amino acids (we named them junctate-1, -2, and -3). The apparent molecular masses of the mouse junctates in SDS-PAGE were in the range between 40 and 53 kDa. Northern and Western blot analyses indicate that mouse junctates are expressed in heart, brain, spleen, lung, liver, kidney, and stomach, but not in skeletal muscle. The apparent molecular weights of junctates from heart and brain were somewhat different from those from the other tissues tested, suggesting that there are tissue-specific expression patterns of the different junctate isoforms. Immunohistochemical studies showed that junctates were expressed both in ventricular and atrial tissues. This is the first study that shows the presence of 3 distinct cardiac junctate isoforms expressed in various mammalian tissues. 相似文献