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161.
Elias Soares de Figueiredo Marcela Massaro Stephanie do Carmo Gilberto José de Moraes 《Experimental & applied acarology》2018,74(1):13-23
Several species of predatory mites, especially those of the family Phytoseiidae, are potentially useful for the control of pest mites and insects. Among the phytoseiids, Euseius concordis (Chant), a species commonly found in South America, has been studied for possible use as biological control agent of pest mites. Given that Euseius species are known to feed on plant leaves and on pollen, the objective of this study was to determine plant species and pollen sources suitable to establish a pilot method of production of that species, based on a set of comparisons in the laboratory. Out of four plant species evaluated in the study, higher survivorship of E. concordis females in the absence of supplementary food was observed on leaflets of Canavalia ensiformis L. Out of two pollen types, higher survivorship was obtained on pollen of Typha domingensis L. In a subsequent step, the population of E. concordis increased 19.3× within 21 days when that pollen of T. domingensis was offered to the predator on plantlets of C. ensiformis, at 25.0 ± 1 °C, 70.0 ± 10% RH and 12 h photophase. Future studies may confirm the economic viability of this setup for the mass production of E. concordis. 相似文献
162.
Length‐weight relationship of 21 fish species from Rio Doce River basin,Minas Gerais,Brazil
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Gilberto N. Salvador Renata G. Frederico Tiago C. Pessali Fábio Vieira Tiago M. S. Freitas 《Zeitschrift fur angewandte Ichthyologie》2018,34(5):1198-1201
The present study provides the length‐weight relationship (LWR) for 21 fish species from eight rivers from Rio Doce River basin, Minas Gerais States, Brazil. Fishes were collected between August 1991 and September 2017, with gillnets, hand nets, cast nets and trawl nets. Standard length and total weight were measured for the LWR, which allometric coefficients b varied from 2.621 to 3.146. 相似文献
163.
Maria Adele Imro Corrado Castagneto Ornella Bosco Paola Modena Lorella Lanza Francesco Puppo Gilberto Filaci Francesco Indiveri Marco Scudeletti 《Cancer immunology, immunotherapy : CII》1995,41(4):210-216
In the present study T lymphocytes isolated from a metastatic lymph node (T-LNL) of a melanoma patient have been cloned. In the attempt to verify whether T-LNL may acquire in vitro functional activities in the absence of tumour-associated antigens, they were cloned utilizing allogeneic lymphocytes as feeder cells. Nineteen clones generated from T-LNL proved to be CD4+ and, among these, five were able to kill autologous and allogeneic human melanoma cells in HLA-class-II-restricted way. On the basis of their cytokine production, these CD4+ cytolytic T-LNL clones were shown to belong to the Th0 subset and three of them expersseed the V17 chain of the T cell receptor. These results suggest the presence of melanomaspecific but functionally inactive lymphocytes with T cell receptor oligoclonality in the lymph node environment. These specific T cells may acquire in vitro the capacity to kill autologous and allogeneic tumours without any induction by autologous melanoma cells. 相似文献
164.
165.
Rafael D. Melani Henrique S. Seckler Owen S. Skinner Luis H. F. Do Vale Adam D. Catherman Pierre C. Havugimana Marcelo Valle de Sousa Gilberto B. Domont Neil L. Kelleher Philip D. Compton 《Journal of visualized experiments : JoVE》2016,(108)
Protein complexes perform an array of crucial cellular functions. Elucidating their non-covalent interactions and dynamics is paramount for understanding the role of complexes in biological systems. While the direct characterization of biomolecular assemblies has become increasingly important in recent years, native fractionation techniques that are compatible with downstream analysis techniques, including mass spectrometry, are necessary to further expand these studies. Nevertheless, the field lacks a high-throughput, wide-range, high-recovery separation method for native protein assemblies. Here, we present clear native gel-eluted liquid fraction entrapment electrophoresis (CN-GELFrEE), which is a novel separation modality for non-covalent protein assemblies. CN-GELFrEE separation performance was demonstrated by fractionating complexes extracted from mouse heart. Fractions were collected over 2 hr and displayed discrete bands ranging from ~30 to 500 kDa. A consistent pattern of increasing molecular weight bandwidths was observed, each ranging ~100 kDa. Further, subsequent reanalysis of native fractions via SDS-PAGE showed molecular-weight shifts consistent with the denaturation of protein complexes. Therefore, CN-GELFrEE was proved to offer the ability to perform high-resolution and high-recovery native separations on protein complexes from a large molecular weight range, providing fractions that are compatible with downstream protein analyses. 相似文献
166.
Emanoella L. Soares Arlete A. Soares Paulo C. Carvalho Gilberto B. Domont Robert W. Thornburg Francisco A. P. Campos 《Proteomics》2016,16(4):629-633
Floral and extrafloral nectaries are unique organs that secrete energy rich chemical components, but their contribution for nectar production is largely unknown. Here, we present the first comparative proteome dataset of four developmental stages of the extrafloral nectaries from castor plant (Ricinus communis), an important biofuel crop. Respectively, from stage I—IV, we identified 626, 613, 449 and 356 proteins, respectively, summing up 882 nonredundant proteins. Surprisingly, we identified two isoforms of the potent toxin ricin, indicating that ricin expression is not limited to seeds, but it may serve a general defense purpose for the castor plant. To date, this is the most complete dataset of proteins either from floral or extrafloral nectaries, thus contributing to lay the foundations for investigations on their ecological and evolutionary importance. 相似文献
167.
The CDKN2A/p16INK4a 5′UTR sequence and translational regulation: impact of novel variants predisposing to melanoma
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Virginia Andreotti Alessandra Bisio Brigitte Bressac‐de Paillerets Mark Harland Odile Cabaret Julia Newton‐Bishop Lorenza Pastorino William Bruno Roberto Bertorelli Veronica De Sanctis Alessandro Provenzani Chiara Menin Gilberto Fronza Paola Queirolo Robert C. Spitale Giovanna Bianchi‐Scarrà Alberto Inga Paola Ghiorzo 《Pigment cell & melanoma research》2016,29(2):210-221
Many variants of uncertain functional significance in cancer susceptibility genes lie in regulatory regions, and clarifying their association with disease risk poses significant challenges. We studied 17 germline variants (nine of which were novel) in the CDKN2A 5′UTR with independent approaches, which included mono and bicistronic reporter assays, Western blot of endogenous protein, and allelic representation after polysomal profiling to investigate their impact on CDKN2A mRNA translation regulation. Two of the novel variants (c.‐27del23, c.‐93‐91delAGG) were classified as causal mutations (score ≥3), along with the c.‐21C>T, c.‐34G>T, and c.‐56G>T, which had already been studied by a subset of assays. The novel c.‐42T>A as well as the previously described c.‐67G>C were classified as potential mutations (score 1 or 2). The remaining variants (c.‐14C>T, c.‐20A>G, c.‐25C>T+c.‐180G>A, c.‐30G>A, c.‐40C>T, c.‐45G>A, c.‐59C>G, c.‐87T>A, c.‐252A>T) were classified as neutral (score 0). In conclusion, we found evidence that nearly half of the variants found in this region had a negative impact on CDKN2A mRNA translation, supporting the hypothesis that 5′UTR can act as a cellular Internal Ribosome Entry Site (IRES) to modulate p16INK4a translation. 相似文献
168.
169.
Debora Russo Gilberto Fronza Laura Ottaggio Paola Monti Chiara Perfumo Alberto Inga Prema Iyer Barry Gold Paola Menichini 《DNA Repair》2010,9(7):728-736
Me-lex is a sequence-specific alkylating agent synthesized to preferentially (>90%) generate N3-methyladenine (3-mA) in the minor groove of double-strand DNA, in A-T rich regions. In this paper we investigated the effect of XRCC1 deficiency in the processing of 3-mA adducts generated by Me-lex, through the molecular analysis of the Hprt mutations and the evaluation of cytogenetic end points such as sister chromatid exchanges (SCEs), micronuclei (MN) and nucleus fragmentation. EM-C11 cells, deficient in XRCC1 activity, showed a 2.5-fold higher sensitivity to the toxicity of Me-lex compared to the DNA repair proficient parental CHO-9 cells, but were not hyper mutable. The spontaneous mutation spectrum at the Hprt locus generated in EM-C11 cells revealed a high percentage of genomic deletions. After Me-lex treatment, the percentage of genomic deletions did not increase, but a class of mutations which appeared to target regulatory regions of the gene significantly increased (p = 0.0277), suggesting that non-coding Hprt genomic sequences represent a strong target for the rare mutations induced by Me-lex. The number of SCEs per chromosome increased 3-fold above background in 50 μМ Me-lex treated CHO-9 cells, while at higher Me-lex concentrations a sharp increase in the percentage of MN and fragmented nuclei was observed. In EM-C11 cells the background level of SCEs (0.939 ± 0.182) was approximately 10-fold higher than in CHO-9 (0.129 ± 0.027) and higher levels of multinucleated cells and MN were also found. In EM-C11, even low doses of Me-lex (25 μM) led to a significant increase in genomic damage. These results indicate that XRCC1 deficiency can lead to genomic instability even in the absence of an exogenous genotoxic insult and low levels of Me-lex-induced lesions, i.e., 3-mA and/or a BER intermediate, can exacerbate this instability. 相似文献
170.
Yadira Magali Bonilla-Sánchez Juan Carlos Serio-Silva Gilberto Pozo-Montuy Colin A. Chapman 《International journal of primatology》2012,33(1):233-245
Reversing forest loss through reforestation has become a critical strategy to decrease global climate change, and such programs
are more likely to be initiated if they can produce a subsequent monetary gain for the host country. As a result, the planting
of monocultures of harvestable trees has become widespread and the practice is accelerating. However, little is known about
the effect of such reforestation strategies on biodiversity. Here we quantify the demographic patterns of a population of
black howlers (Alouatta pigra) living in a 200-ha eucalyptus plantation with connected remnant forests in southeastern Mexico. We compare our results to
data from the literature from forest fragments, extensive forest tracts, and different agrosystems. The howler population
inhabiting the plantation grew from 69 individuals in 2007 to 77 in 2008 (11.6% growth) and to 84 in 2009 (9.1% growth). During
this time the howlers fed extensively on the native vegetation that was growing under the eucalyptus, vines that grew on the
plantation trees, and adjacent areas of native secondary growth, but they almost never fed on eucalyptus. Howler density in
the plantation was greater than in extensive forest tracts or forest fragments, whereas mean group size was similar to that
in the forest tracts and greater than in the fragments and agrosystems. There was no apparent difference in the adult female-to-immature
ratio among sites. Our results indicate that plantations that have associated native vegetation can play a positive role in
the conservation of this species, but suggest that harvesting regimens must be carefully orchestrated to prevent associated
food scarcity. 相似文献