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1.
Graziele Fonseca de Sousa Maira de Assis Lima Débora Fernandes Custodio Vanessa Morais Freitas Gisele Monteiro 《PloS one》2015,10(12)
The use of carboplatin in cancer chemotherapy is limited by the emergence of drug resistance. To understand the molecular basis for this resistance, a chemogenomic screen was performed in 53 yeast mutants that had previously presented strong sensitivity to this widely used anticancer agent. Thirty-four mutants were responsive to carboplatin, and from these, 21 genes were selected for further studies because they have human homologues. Sixty percent of these yeast genes possessed human homologues which encoded proteins that interact with cullin scaffolds of ubiquitin ligases, or whose mRNA are under the regulation of Human antigen R (HuR) protein. Both HuR and cullin proteins are regulated through NEDDylation post-translational modification, and so our results indicate that inhibition of this process should sensitise resistant tumour cells to carboplatin. We showed that treatment of a tumour cell line with MLN4924, a NEDDylation inhibitor, overcame the resistance to carboplatin. Our data suggest that inhibition of NEDDylation may be a useful strategy to resensitise tumour cells in patients that have acquired carboplatin resistance. 相似文献
2.
Apical Chlorosis Disease of Chickpea (Cicer arietinum) Caused by Tomato Spotted Wilt Virus in Brazil
L. S. Botteux A. C. De Ávila L. B. Giordano M. I. Lima E. W. Kitajima 《Journal of Phytopathology》1995,143(10):629-631
A severe new disease was observed in field-grown chickpea (Cicer arietinum L.) plants in Brasilia-DF, central Brazil. Symptoms were mainly general chlorosis accompanied by necrosis of the new growth and plant stunting, but pods were symptomless. Host range studies, serology, particle morphology, and cytopathology showed that tomato-spotted wilt tospovirus (TSWV) was the cause of the disease. This is apparently the first report of a chickpea disease caused by natural infection of a tospovirus. 相似文献
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In the red howler monkey, Alouatta seniculus stramineus (2n = 47, 48, or 49), variations in diploid chromosome number are due to different numbers of microchromosomes. Males exhibit a Y;autosome translocation involving the short arm of an individual biarmed autosome. Consequently, the sex-chromosome constitution in the male is X1X2Y1Y2, with X1 representing the original X chromosome, X2 the biarmed autosome (No. 7), Y1 the Y;7p translocation product, and Y2 the acrocentric homolog of 7q. In the first meiotic division, a quadrivalent with a chain configuration can be observed in spermatocytes. Females have an X1X1X2X2 sex-chromosome constitution. Chromosome heteromorphisms were observed in pair 13, due to a pericentric inversion, and pair 19, due to the presence of constitutive heterochromatin. Microchromosomes, which varied in number between individuals, were also heterochromatic. NOR-staining was observed at two separate sites on a single chromosome pair (No. 10). A comparison of A.s. stramineus with A.s. macconnelli shows that these two subspecies have identical diploid chromosome numbers (47, 48, or 49), again due to a varying number of microchromosomes, and that they share a similar sex-chromosome constitution. Their karyotypes, however, are not identical, but can be derived from each other by a reciprocal translocation. Further comparisons with other A. seniculus subspecies reported in the literature indicate that this taxon is not karyologically uniform and that substantial chromosome shuffling has occurred between populations that have been considered to be subspecies by taxonomic criteria based on their morphometric attributes. 相似文献
5.
N C Bethlenfalvay J E Lima T L Waldrup E Chadwick I Stewart 《Comparative biochemistry and physiology. A, Comparative physiology》1988,89(2):113-117
1. G-6-P, F-6-P, F-1, 6-P, DHAP and GA-3-P in opossum erythrocytes were found at levels above those reported in human red cells. 2. About 1% of the radioactivity provided as [1-14C] DOG to red cells of both species was recovered as 14CO2 in 1 hr. 3. Unlike [1-14C] DOG, radiochromatography of extracts of cells incubated DOG revealed two diffusible radiolabelled compounds in the supernatant of cell suspensions. 4. The catabolism of DOG was quantitatively and qualitatively similar in opossum and human erythrocytes under the conditions of this study. 相似文献
6.
Natalia Cadaxo Rochael Luize Gon?alves Lima Sandra Maria Pereira de Oliveira Marcello André Barcinski Elvira Maria Saraiva Robson Queiroz Monteiro Lucia Helena Pinto-da-Silva 《Memórias do Instituto Oswaldo Cruz》2013,108(6):679-685
Leishmania parasites expose phosphatidylserine (PS) on their
surface, a process that has been associated with regulation of host''s immune
responses. In this study we demonstrate that PS exposure by metacyclic
promastigotes of Leishmania amazonensis favours blood
coagulation. L. amazonensis accelerates in vitro coagulation of
human plasma. In addition, L. amazonensis supports the assembly
of the prothrombinase complex, thus promoting thrombin formation. This process
was reversed by annexin V which blocks PS binding sites. During blood meal,
Lutzomyia longipalpis sandfly inject saliva in the bite
site, which has a series of pharmacologically active compounds that inhibit
blood coagulation. Since saliva and parasites are co-injected in the host during
natural transmission, we evaluated the anticoagulant properties of sandfly
saliva in counteracting the procoagulant activity of L.
amazonensis . Lu. longipalpis saliva reverses
plasma clotting promoted by promastigotes. It also inhibits thrombin formation
by the prothrombinase complex assembled either in phosphatidylcholine (PC)/PS
vesicles or in L. amazonensis . Sandfly saliva inhibits factor
X activation by the intrinsic tenase complex assembled on PC/PS vesicles and
blocks factor Xa catalytic activity. Altogether our results show that metacyclic
promastigotes of L. amazonensis are procoagulant due to PS
exposure. Notably, this effect is efficiently counteracted by sandfly
saliva. 相似文献
7.
Rosalem Gabriel Santos Las Casas Estevam Barbosa Lima Thiago Parente González-Torres Libardo Andrés 《Biomechanics and modeling in mechanobiology》2020,19(5):1537-1549
Biomechanics and Modeling in Mechanobiology - Cell migration is a process of crucial importance for the human body. It is responsible for important processes such as wound healing and tumor... 相似文献
8.
S. Goldenberg J.M. Salles V.T. Contreras M.P.Lima Franco A.M. Katzin W. Colli C.M. Morel 《FEBS letters》1985,180(2):265-270
The cell-free translation products of polyribosomal and post-polyribosomal mRNAs from the non-infective epimastigotes and the infective metacyclic trypomastigotes of the parasitic protozoan Trypanosoma cruzi were compared by two-dimensional polyacrylamide gel electrophoresis. The result show that although many polypeptides are conserved, quantitative and qualitative differences are observed between both differentiation stages. The results also indicate the existence of post-polyribosomal mRNAs in equilibrium with polyribosomal counterparts. The immunoprecipitation of the in vitro synthesized polypeptides with chagasic human serum and the serum raised against an 85-kDa glycoprotein (P2-WGA), potentially involved in the process of T. cruzi penetration into mammalian cells, shows that while the chagasic serum recognizes the same 72-kDa, 68-kDa and 46-kDa polypeptides in both differentiation stages, the anti-P2-WGA serum immunoprecipitates a single 48-kDa polypeptide from in vitro translation products of metacyclic trypomastigotes. 相似文献
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10.
João Paulo Rodrigues Martins Luiz Carlos de Almeida Rodrigues Lorenzo Toscano Conde Andreia Barcelos Passos Lima Gontijo Antelmo Ralph Falqueto 《Plant biosystems》2020,154(1):87-99
AbstractUnder in vitro culture conditions, plants may present physiological and anatomical disorders, which can interfere negatively after ex vitro transfer. The aim of this investigation was to analyze the impacts of natural ventilation and sucrose supply on the anatomy and physiology of Vriesea imperialis. Plants previously grown in vitro were transferred to culture medium containing 0, 15, 30 or 45?g L?1 sucrose. Three different culture container sealing systems were tested: lids with a green filter (81.35 gas exchanges per day), yellow filter (13.09 gas exchanges per day) or lids with a yellow filter covered with three layers of transparent polyvinylchloride (PVC) film (blocking fluent gas exchange). Sucrose concentrations influenced thickness, lignin and suberin deposition of exodermis cell wall. The modifications verified in leaves, such as higher density of stomata and trichome scales, showed that sucrose can induce osmotic stress in the plants. Photomixotrophic conditions, using containers with intermediate rate of gas exchange (yellow filter) and with 15–30?g L?1 sucrose, produced an improvement in the growth traits and did not induce anatomical and physiological disturbances. 相似文献