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521.
Soula Danopoulos Sara Parsa Denise Al Alam Reza Tabatabai Sheryl Baptista Caterina Tiozzo Gianni Carraro Matthew Wheeler Guillermo Barreto Thomas Braun Xiaokun Li Mohammad K. Hajihosseini Saverio Bellusci 《PloS one》2013,8(10)
The vertebrate limbs develop through coordinated series of inductive, growth and patterning events. Fibroblast Growth Factor receptor 2b (FGFR2b) signaling controls the induction of the Apical Ectodermal Ridge (AER) but its putative roles in limb outgrowth and patterning, as well as in AER morphology and cell behavior have remained unclear. We have investigated these roles through graded and reversible expression of soluble dominant-negative FGFR2b molecules at various times during mouse limb development, using a doxycycline/transactivator/tet(O)-responsive system. Transient attenuation (≤24 hours) of FGFR2b-ligands signaling at E8.5, prior to limb bud induction, leads mostly to the loss or truncation of proximal skeletal elements with less severe impact on distal elements. Attenuation from E9.5 onwards, however, has an irreversible effect on the stability of the AER, resulting in a progressive loss of distal limb skeletal elements. The primary consequences of FGFR2b-ligands attenuation is a transient loss of cell adhesion and down-regulation of P63, β1-integrin and E-cadherin, and a permanent loss of cellular β-catenin organization and WNT signaling within the AER. Combined, these effects lead to the progressive transformation of the AER cells from pluristratified to squamous epithelial-like cells within 24 hours of doxycycline administration. These findings show that FGFR2b-ligands signaling has critical stage-specific roles in maintaining the AER during limb development. 相似文献
522.
Larissa Cardoso Corrêa Araújo Jaciana Santos Aguiar Thiago Henrique Napole?o Fernanda Virgínia Barreto Mota André Luiz Souza Barros Maiara Celine Moura Marília?Cavalcanti Coriolano Luana Cassandra Breitenbach Barroso Coelho Teresinha Gon?alves Silva Patrícia Maria Guedes Paiva 《PloS one》2013,8(12)
Background
The extract from Moringa oleifera seeds is used worldwide, especially in rural areas of developing countries, to treat drinking water. M. oleifera seeds contain the lectins cmol and WSMoL, which are carbohydrate-binding proteins that are able to reduce water turbidity because of their coagulant activity. Studies investigating the ability of natural products to damage normal cells are essential for the safe use of these substances. This study evaluated the cytotoxic and anti-inflammatory properties of the aqueous seed extract, the extract used by population to treat water (named diluted seed extract in this work), and the isolated lectins cmol and WSMoL.Methodology/Principal Findings
The data showed that the aqueous seed extract and cmol were potentially cytotoxic to human peripheral blood mononuclear cells, while WSMoL and diluted seed extract were not cytotoxic. The M. oleifera aqueous seed extract and the lectins cmol and WSMoL were weakly/moderately cytotoxic to the NCI-H292, HT-29 and HEp-2 cancer cell lines and were not hemolytic to murine erythrocytes. Evaluation of acute toxicity in mice revealed that the aqueous seed extract (2.000 mg/kg) did not cause systemic toxicity. The aqueous seed extract, cmol and WSMoL (6.25 µg/mL) and diluted seed extract at 50 µg/mL exhibited anti-inflammatory activity on lipopolyssaccharide-stimulated murine macrophages by regulating the production of nitric oxide, TNF-α and IL-1β. The aqueous seed extract reduced leukocyte migration in a mouse model of carrageenan-induced pleurisy; the myeloperoxidase activity and nitric oxide, TNF-α and IL-1β levels were similarly reduced. Histological analysis of the lungs showed that the extract reduced the number of leukocytes.Conclusion/Significance
This study shows that the extract prepared according to folk use and WSMoL may be non-toxic to mammalian cells; however, the aqueous seed extract and cmol may be cytotoxic to immune cells which may explain the immunosuppressive potential of the extract. 相似文献523.
524.
Mello-Silva CC Vilar MM Bezerra JC Vasconcellos MC Pinheiro J Rodrigues Mde L 《Memórias do Instituto Oswaldo Cruz》2007,102(6):671-674
The reproductive activity of Biomphalaria glabrata exposed to Euphorbia splendens var. hislopii latex was evaluated. Parameters related to fecundity and fertility were observed. The snails were exposed to the LD50 (1 mg/l) of crude latex. At the first week post exposure (p.e.), the egg laying was reduced. After the fourth week p.e., an increase of the number of eggs/snail occurred. The results showed a marked reduction in the hatching of the snails, revealing an interference of latex exposure with the reproductive process of B. glabrata of E. splendens var. hislopii. The LD50 of the latex may be used as an alternative method to control the size of the populations of B. glabrata in field. 相似文献
525.
Characteristics of seminal plasma proteins and their correlation with canine semen analysis 总被引:1,自引:0,他引:1
The objectives were to separate canine seminal plasma proteins (with SDS-PAGE) and to determine the correlation between specific proteins and semen characteristics. Three ejaculates from 20 mixed-breed dogs, of unknown fertility, were collected by digital manipulation. Ejaculate volume and color, sperm motility, sperm vigor, percentage of morphologically normal spermatozoa, and membrane integrity (hypoosmotic swelling test and fluorescent staining) were assessed. For each dog, seminal plasma was pooled from all three ejaculates and proteins were separated with SDS-PAGE, using polyacrylamide concentrations of 13% and 22% in the separation gels. After staining, gel images were digitized to estimate molecular weights (MW) and integrated optical density (IOD) of each lane and of individual bands. Total seminal plasma protein concentration was 2.19+/-1.56 g/dL (mean+/-SD; range 1.12-5.19 g/dL). A total of 37 protein bands were identified (although no dog had all 37 bands). In the 13% gel, molecular weights ranged from 100.6 to 17.1 kDa, with four bands (49.7, 33.2, 26.4, and 19.5 kDa) present in samples from all dogs. In the 22% gel, molecular weights ranged from 15.6 to 3.6 kDa, with nine bands (15.6, 13.5, 12.7, 11.7, 10.5, 8.7, 7.8, 5.6, and 4.9 kDa) present in samples from all dogs. Combined for both gels, the majority of bands (85%) had molecular weights <17 kDa, with B20 (15.6 kDa) in high concentrations in samples from all dogs. There were positive correlations (P < or = 0.01) between two bands, B4 (67 kDa) and B5 (58.6 kDa), and sperm motility (r=0.66 and r=0.46), sperm vigor (r=0.56 and r=0.66), percentage of morphologically normal spermatozoa (r=0.55 and r=0.59), the hypoosmotic swelling test (r=0.76 and r=0.68), and fluorescent staining (r=0.56 and r=0.59), respectively. In conclusion, 37 proteins were identified in seminal plasma; two were significantly correlated with semen characteristics. 相似文献
526.
Schneider Naira Fernanda Zanchett Menegaz Danusa Dagostin Andre Luiz Andreotti Persich Lara Rocha Sayonarah C. Ramos Ana Carolina Pacheco Cortes Vanessa Faria Fontes Carlos Frederico Leite de Pádua Rodrigo Maia Munkert Jennifer Kreis Wolfgang Braga Fernão Castro Barbosa Leandro A. Silva Fátima Regina Mena Barreto Simões Cláudia Maria Oliveira 《Molecular and cellular biochemistry》2021,476(4):1825-1848
Molecular and Cellular Biochemistry - Cardiac glycosides (CGs) are useful drugs to treat cardiac illnesses and have potent cytotoxic and anticancer effects in cultured cells and animal models.... 相似文献
527.
Barreto André Pinto Wilson Rodrigues Andreia Rocha Rui J. M. Unamunzaga Carlos Silva Tomé Dias Jorge Conceição Luis E. C. 《Journal of applied phycology》2021,33(4):2233-2240
Journal of Applied Phycology - Microalgae are one of the most promising groups of functional ingredients for inclusion in microdiets for Senegalese sole (Solea senegalensis) larvae, supplying... 相似文献
528.
Braz Tavares da Hora Júnior Davi Mesquita de Macedo Robert Weingart Barreto Harry C. Evans Carlos Raimundo Reis Mattos Luiz Antonio Maffia Eduardo S. G. Mizubuti 《PloS one》2014,9(8)
Background
South American leaf blight (SALB) of rubber has been the main constraint to production in its neotropical centre of origin since commercial plantations were first established. The fungal causal agent was identified and described more than a century ago but its precise placement within the Ascomycota still remains uncertain. Indeed, such is the ambiguity surrounding the pathogen that each of the spore morphs would, according to their present classification, be placed in different ascomycete families: the Microcyclus sexual morph in the Planistromellaceae and the two purported asexual morphs - Fusicladium and Aposphaeria – in the Venturiaceae and Lophiostomataceae, respectively. Given the historical importance of the fungus and the ever-menacing threat that it poses to rubber production in the Palaeotropics – and, thus to the rubber industry and to the global economy – its phylogeny, as well as its biology, should be resolved as a matter of urgency.Methods and Results
Here, six genomic regions (LSU rRNA, mtSSU, MCM7, EF-1α, Act and ITS) were used for reconstructing the molecular phylogeny of the SALB fungus based on material collected throughout Brazil. The analyses support the classification of the fungus in the family Mycosphaerellaceae s. str. (Capnodiales, Dothideomycetes) and place it firmly within the clade Pseudocercospora s. str., now accepted as one of the distinct genera within Mycosphaerellaceae. The new combination Pseudocercospora ulei is proposed and the life cycle of the fungus is confirmed, based on both experimental and phylogenetic evidence, with the Aposphaeria morph shown to have a spermatial rather than an infective-dispersal function.Conclusions
Because the phylogeny of the SALB fungus has now been clarified, new insights of its epidemiology and genomics can be gained following comparison with closely-related, better-researched crop pathogens. 相似文献529.
Andressa Jisely Barreto Barbosa Iracilda Sampaio Horacio Schneider Simoni Santos 《PloS one》2014,9(7)
The phylogenetic relationships within the Stellifer group of weakfishes (Stellifer, Odontoscion, Ophioscion, and Bairdiella) were evaluated using 2723 base pairs comprising sequences of nuclear (rhodopsin, TMO-4C4, RAG-1) and mitochondrial (16S rRNA and COI) markers obtained from specimens of nine species. Our results indicate a close relationship between Bairdiella and Odontoscion, and also that the genus Stellifer is not monophyletic, but rather that it consists of two distinct lineages, one clade containing S. microps/S. naso/S. brasiliensis and the other, S. rastrifer/S. stellifer/Stellifer sp. B, which is closer to Ophioscion than the former clade. The O. punctatissimus populations from the northern and southern Brazilian coast were also highly divergent in both nuclear (0.8% for rhodopsin and 0.9% for RAG-1) and mitochondrial sequences (2.2% for 16S rRNA and 7.3% for COI), which we conclude is consistent with the presence of two distinct species. The morphological similarities of the members of the Stellifer group is reinforced by the molecular data from both the present study and previous analyses, which have questioned the taxonomic status of the Stellifer group. If, on the one hand, the group is in fact composed of four genera (Stellifer, Ophioscion, Odontoscion, and Bairdiella), one of the two Stellifer clades should be reclassified as a new genus. However, if the close relationship and the reduced genetic divergence found within the group is confirmed in a more extensive study, including representatives of additional taxa, this, together with the morphological evidence, would support downgrading the whole group to a single genus. Obviously, these contradictory findings reinforce the need for a more systematic taxonomic revision of the Stellifer group as a whole. 相似文献
530.
Thessika Hialla Almeida Araujo Fernanda Khouri Barreto Alcantara Luiz Carlos Júnior Aline Cristina Andrade Mota Miranda 《Memórias do Instituto Oswaldo Cruz》2014,109(4):448-451
Human T-cell lymphotropic virus type 1 (HTLV-1) is mainly associated with two
diseases: tropical spastic paraparesis/HTLV-1-associated myelopathy (TSP/HAM) and
adult T-cell leukaemia/lymphoma. This retrovirus infects five-10 million individuals
throughout the world. Previously, we developed a database that annotates sequence
data from GenBank and the present study aimed to describe the clinical, molecular and
epidemiological scenarios of HTLV-1 infection through the stored sequences in this
database. A total of 2,545 registered complete and partial sequences of HTLV-1 were
collected and 1,967 (77.3%) of those sequences represented unique isolates. Among
these isolates, 93% contained geographic origin information and only 39% were related
to any clinical status. A total of 1,091 sequences contained information about the
geographic origin and viral subtype and 93% of these sequences were identified as
subtype “a”. Ethnicity data are very scarce. Regarding clinical status data, 29% of
the sequences were generated from TSP/HAM and 67.8% from healthy carrier individuals.
Although the data mining enabled some inferences about specific aspects of HTLV-1
infection to be made, due to the relative scarcity of data of available sequences, it
was not possible to delineate a global scenario of HTLV-1 infection. 相似文献