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1.
Ecotoxicology ; 30(6): 1056-1070, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34152527

RESUMO

Agriculture insecticides are used against insect pest species, but are able to change community structure in contaminated habitats, and also the genetic pool of exposed individuals. In fact, the latter effect is a relevant tool to in situ biomonitoring of pollutant contamination and impact, besides its practical economic and management concerns. This takes place because the emergence of individuals with resistance to insecticides is particularly frequent among insect pest species and usually enhances insecticide overuse and crop losses. Pest insects of global prominence such as whiteflies are a focus of attention due to problems with insecticide resistance and association with endosymbionts, as the case of the invasive putative species Bemisia tabaci MEAM1. The scenario is particularly complex in the Neotropics, where insecticide use is ubiquitous, but whose spatial scale of occurrence is usually neglected. Here we explored the spatial-dependence of both phenomena in MEAM1 whiteflies recording resistance to two widely used insecticides, lambda-cyhalothrin and spiromesifen, and endosymbiont co-occurrence. Resistance to both insecticides was frequent exhibiting low to moderate frequency of lambda-cyhalothrin resistance and moderate to high frequency of spiromesifen resistance. Among the prevailing whitefly endosymbionts, Wolbachia, Cardinium and Arsenophonus were markedly absent. In contrast, Hamiltonella and Rickettsia prevailed and their incidence was correlated. Furthermore, Rickettsia endosymbionts were particularly associated with lambda-cyhalothrin susceptibility. These traits were spatially dependent with significant variation taking place within an area of about 700 Km2. Such findings reinforce the notion of endosymbiont-associated resistance to insecticides, and also of their local incidence allowing spatial mapping and locally-targeted mitigation.


Assuntos
Hemípteros , Inseticidas , Animais , Humanos , Incidência , Resistência a Inseticidas , Inseticidas/toxicidade , Simbiose
2.
Arch Virol ; 165(1): 253-256, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31758274

RESUMO

In Brazil, non-cultivated plants, especially weeds, are infected with a diversity of begomoviruses and often show striking golden mosaic symptoms. In the present study, leaves showing these symptoms were collected from Sida sp. plants in Guadalupe, Piaui State, Northeastern Brazil, in 2015 and 2016. PCR tests with degenerate primers revealed the presence of begomovirus DNA-A and DNA-B components. Restriction enzyme digestion of rolling circle-amplified DNA revealed fragments totaling ~5.2 kb, indicating infection by a bipartite begomovirus. The DNA-A and DNA-B components have a genome organization typical of New World (NW) bipartite begomoviruses and a common region of 220 nucleotides (nt) with 96% identity, indicating these are cognate components. Comparisons performed with the DNA-A sequence revealed the highest nt sequence identity (84%) with that of sida angular mosaic virus (SiAMV), whereas those performed with the DNA-B sequence revealed highest identity (77%) with that of sida chlorotic vein virus (SiCVV). In phylogenetic analyses, the DNA-A sequence was placed in a strongly supported clade with SiAMV and SiCVV from Piaui, whereas the DNA-B sequence was placed in a clade with SiCVV and corchorus mottle virus. Based on the current ICTV criteria for the demarcation of begomovirus species (<91% nt sequence identity for the DNA-A component), this is a member of a new species for which the name "Sida yellow golden mosaic virus" is proposed.


Assuntos
Begomovirus/genética , Sida (Planta)/virologia , Sequenciamento Completo do Genoma/métodos , Begomovirus/classificação , Brasil , Genoma Viral , Guadalupe , Filogenia
3.
Arch Virol ; 163(3): 737-743, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29224131

RESUMO

A new begomovirus species was identified from tomato plants with upward leaf curling and purple vein symptoms, which was first identified in the Piaui state of Northeast (NE) Brazil in 2014. Tomato leaf samples were collected in 2014 and 2016, and PCR with degenerate primers revealed begomovirus infection. Rolling circle amplification and restriction enzyme digestion indicated a single genomic DNA of ~ 2.6 kb. Cloning and sequencing revealed a genome organization similar to DNA-A components of New World (NW) bipartite begomoviruses, with no DNA-B. The complete nucleotide sequence had the highest identity (80%) with the DNA-A of Macroptilium yellow spot virus (MacYSV), and phylogenetic analyses showed it is a NW begomovirus that clusters with MacYSV and Blainvillea yellow spot virus, also from NE Brazil. Tomato plants agroinoculated with a dimeric clone of this genomic DNA developed upward leaf curling and purple vein symptoms, indistinguishable from those observed in the field. Based on agroinoculation, this virus has a narrow host range, mainly within the family Solanaceae. Co-inoculation experiments with tomato severe rugose virus and tomato mottle leaf curl virus, the two predominant begomoviruses infecting tomato in Brazil, revealed a synergistic interaction among these begomoviruses. The name Tomato leaf curl purple vein virus (ToLCPVV) is proposed for this new begomovirus.


Assuntos
Begomovirus/genética , DNA Viral/genética , Genoma Viral , Filogenia , Folhas de Planta/virologia , Solanum lycopersicum/virologia , Begomovirus/classificação , Begomovirus/isolamento & purificação , Brasil , Sequenciamento de Nucleotídeos em Larga Escala , Especificidade de Hospedeiro , Doenças das Plantas/virologia , Análise de Sequência de DNA
5.
Plant Dis ; 98(5): 699, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-30708517

RESUMO

One of the most important invasive and harmful members of the genus Begomovirus (family Geminiviridae) is the monopartite Tomato yellow leaf curl virus (TYLCV), which is widespread over the world associated with tomato yellow leaf curl disease (TYLCD). Tomato (Solanum lycopersicum) plants infected with TYLCV show upward leaf curling and yellowing. In Latin America, isolates of TYLCV have been reported from Cuba, the Dominican Republic, Mexico and Puerto Rico (1), Guatemala (GenBank Accession No. GU355941), and Venezuela (partial genome sequence DQ302033). In Costa Rica, only isolates of the bipartite begomoviruses Tomato leaf curl Sinaloa virus (TLCSiV) (3) and Tomato yellow mottle virus (KC176780, KC176781) have been reported infecting tomatoes. During a survey conducted in 2012, similar begomovirus-like symptoms (leaf yellowing and upward leaf curling) were observed in tomato plants of five commercial growing areas in the Central Valley (Grecia region) of Costa Rica. In total, 65 tomato samples were randomly collected, 14 from greenhouses and 41 from open fields. Symptoms of upward leaf curling and yellowing were observed in three samples. Total DNA was extracted from collected samples and tested by dot blot hybridization using a probe to the coat protein (CP) gene of a Guatemalan isolate of Bean golden yellow mosaic virus (3). Only the three symptomatic samples tested positive, which represents an incidence of 14% (2 samples) in greenhouses and 2.4% (1 sample) in open field crops. These samples were subjected to rolling circle amplification (RCA) for viral circular genome amplification (2). The amplified products were then digested with MspI restriction endonuclease, which resulted into DNA fragments of 2,320 and 458 bp for all three samples. This suggested infection with a monopartite begomovirus. In order to obtain the full-length clone, the RCA product of two samples (5240 and 5241) was digested with BamHI, and the ~2.8 kb DNA fragment was cloned into pBluescript II SK(+) (Stratagene, La Jolla, CA) vector. After transformation of Escherichia coli DH5α, recombinant plasmids with inserts of expected size were selected and the insert was sequenced by primer walking (Macrogen Inc., Korea). The inserts of three clones from the two samples (CR:5240-16:2012, CR:5240-17:2012, and CR:5241-14:2012) were sequenced (deposited in GenBank as KF533855, KF533856, and KF533857, respectively). Sequences were all 2,781 nt long and shared 100% identity between themselves (1-nt mismatch between CR:5240-16:2012 and CR:5240-17:2012, and CR:5240-16:2012 and CR:5241-14:2012; and 2-nt mismatches between CR:5240-17:2012 and CR:5241-14:2012) and 99% with the sequence of Tomato yellow leaf curl virus-Israel[Japan:Haruno:2005] (TYLCV-IL[JR:Har:05]) (AB192966). These sequences represented full length genomes of isolates of the monopartite begomovirus TYLCV-IL and grouped in a phylogenetic clade (4) that comprised TYLCV-IL isolates reported from Asia (China and Japan) and from Mexico, while more distantly related to the clade comprising TYLCV-IL isolates reported from Central America (Cuba, Guatemala, Puerto Rico) and the United States, suggesting a distinct introduction event in Costa Rica. This is the first report of the presence of TYLCV in Costa Rica, therefore it is imperative to study the incidence and geographical spread of this virus in the country as well as its genetic diversity, since TYLCV infections might lead to significant yield losses, as reported in other countries. References: (1) A. M. Idris et al. Plant Dis. 83:303, 1999. (2) A. K. Inoue-Nagata et al. J. Virol. Methods 116:209, 2004. (3) M. K. Nakla et al. Acta Hortic. 695:277, 2005. (4) K. Tamura et al. Mol. Biol. Evol. 28:2731, 2011.

6.
Eur J Gynaecol Oncol ; 35(1): 91-4, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24654472

RESUMO

The authors report a rare case of peritoneal adenomatoid mesothelioma in a woman with no history of asbestos exposure. A 61-year-old woman was originally suspected of having a bilateral ovarian tumor based on chest radiography and magnetic resonance imaging (MRI). Upon referral to our hospital, the presence of two solid masses was confirmed by enhanced MRI and 18F-fluorodeoxyglucose positron-emission tomography/computed tomography (18F-FDG-PET/CT). Physical examination was normal, as were serum concentrations of the tumor markers CA 19-9, CA 125, and CEA. Laparoscopic surgery showed a right ovarian tumor and laparoscopic right salpingo-oophorectomy and adhesiotomy were performed. Two months later, the patient underwent laparoscopic segmental resection of the sigmoid colon, with histological analysis identifying an adenomatoid-like tumor. The final diagnosis was peritoneal adenomatoid-like mesothelioma with invasion of the right ovary. This case report demonstrates that imaging techniques must be coupled with laparoscopic surgery for an accurate diagnosis of peritoneal mesothelioma.


Assuntos
Mesotelioma/cirurgia , Tumor Adenomatoide/diagnóstico , Tumor Adenomatoide/patologia , Tumor Adenomatoide/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Laparoscopia , Mesotelioma/diagnóstico , Mesotelioma/patologia , Pessoa de Meia-Idade , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/cirurgia , Neoplasias Peritoneais/diagnóstico , Neoplasias Peritoneais/patologia , Neoplasias Peritoneais/cirurgia
7.
Phytopathology ; 103(5): 436-44, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23489523

RESUMO

Tomato severe rugose virus (ToSRV) is the most important begomovirus species in Brazilian tomato production. Many weeds are associated with tomato, and some are hosts of begomoviruses. Only one species of weed, Nicandra physaloides, has been found to be infected with ToSRV. In this study, four weed species were investigated for their capacity to be infected by ToSRV and serve as a potential source of inoculum for tomato. Begomoviruses from naturally infected Crotalaria spp., Euphorbia heterophylla, N. physaloides, and Sida spp. were successfully transferred to tomato plants by biolistic inoculation. ToSRV was the major virus transferred to tomato. In contrast, other begomoviruses were transferred to weeds, such as Sida micrantha mosaic virus and Euphorbia yellow mosaic virus. Furthermore, a new strain of Sida micrantha mosaic virus is reported. We also confirmed that Crotalaria spp., E. heterophylla, and Sida spp. are infected with ToSRV but at low viral titers and in mixed infections with weed-infecting begomoviruses. Thus, it was demonstrated that weeds are potential sources of ToSRV for tomato in central Brazil.


Assuntos
Begomovirus/isolamento & purificação , Crotalaria/virologia , Euphorbia/virologia , Malvaceae/virologia , Plantas Daninhas/virologia , Solanum lycopersicum/virologia , Sequência de Bases , Begomovirus/genética , Begomovirus/fisiologia , Brasil , Clonagem Molecular , Coinfecção , Primers do DNA/genética , DNA Viral/genética , Genoma Viral/genética , Dados de Sequência Molecular , Doenças das Plantas/virologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA , Solanaceae/virologia , Especificidade da Espécie
8.
Int J Sports Med ; 34(5): 398-401, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23152129

RESUMO

Many of the published data on the lipid profile of athletes is based on studies of endurance athletes. The data on soccer players are rare. The purpose of this study was to examine serum high-density lipoprotein cholesterol subfractions and lecithin:cholesterol acyltransferase activity in collegiate soccer players. 31 well-trained male collegiate soccer players were divided into 2 groups: 16 defenders and 15 offenders. They were compared with 16 sedentary controls. Dietary information was obtained with a food frequency questionnaire. The subjects were all non-smokers and were not taking any drug known to affect the lipid and lipoprotein metabolism. The offenders had significantly higher high-density lipoprotein cholesterol, high-density lipoprotein2 cholesterol, and apolipoprotein A-I than the defenders and controls, whereas the defenders had the significantly higher high-density lipoprotein2 cholesterol than the controls. Both groups of athletes had significantly higher lecithin:cholesterol acyltransferase activity than the controls. The results indicate that favorable lipid and lipoprotein profile could be obtained by vigorous soccer training.


Assuntos
Apolipoproteína A-I/sangue , HDL-Colesterol/sangue , Fosfatidilcolina-Esterol O-Aciltransferase/sangue , Futebol/fisiologia , Adolescente , Biomarcadores/sangue , Inquéritos sobre Dietas , Humanos , Japão , Masculino , Adulto Jovem
9.
Arch Virol ; 157(7): 1397-401, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22527869

RESUMO

The complete genomic sequence of pepper yellow mosaic virus (PepYMV), a member of the genus Potyvirus, was determined. The sequence was 9745 nucleotides long, excluding the 3' poly(A) tail. The genome contained a large open reading frame encoding a polyprotein of 3085 amino acids, which contained the typically conserved motifs found in members of the genus Potyvirus and an additional P3-PIPO (pretty interesting potyvirus ORF). In a pairwise comparison with other potyvirus sequences, the full genome of PepYMV shared a maximum of 63.84 % nucleotide sequence identity with pepper mottle virus (PepMoV), followed by verbena virus Y (VVY, 62.11 %), potato virus Y (PVY, 62.07 %) and Peru tomato mosaic virus (PTV, 62.00 %). Based upon a phylogenetic analysis, PepYMV was most closely related to PepMoV and PTV, within the PVY subgroup cluster, like most potyviruses isolated in solanaceous hosts in South America.


Assuntos
Potyvirus/genética , RNA Viral/genética , Sequência de Bases , Brasil , Capsicum/virologia , DNA Complementar/química , Regulação Viral da Expressão Gênica/fisiologia , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Potyvirus/classificação , Alinhamento de Sequência , Proteínas Virais/química , Proteínas Virais/genética
10.
Virus Genes ; 40(1): 140-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19937269

RESUMO

Tomato yellow vein streak virus (ToYVSV) is a tentative begomovirus (Family Geminiviridae) species that seriously affects tomato and potato production in Brazil. Here, we have determined the genomic and biological characteristics of a ToYVSV isolate (Ba3) from a potato plant sampled in Rio Grande do Sul State, Brazil. The DNA-A nucleotide sequence of Ba3 and another previously reported ToYVSV isolate share 89.7% sequence identity. These ToYVSV isolates should be classified as a new species in that they are most closely related to Soybean blistering mosaic virus with which they share only approximately 80% identity. Cloned constructs containing 1.5 mer copies of the ToYVSV genomic components were found, by biolistic bombardment, to be infectious in at least 11 plant species in 2 families (Solanaceae and Malvaceae). Symptoms on tomato and potato plants were identical to those originally observed on field-infected plants. ToYVSV was also sap-transmissible from Nicotiana benthamiana to N. benthamiana and tomato, but not to potato plants.


Assuntos
Begomovirus/genética , Doenças das Plantas/virologia , Solanum lycopersicum/virologia , Sequência de Bases , Begomovirus/isolamento & purificação , Begomovirus/fisiologia , Brasil , Genoma de Planta , Filogenia , Solanum tuberosum/virologia
11.
Arch Virol ; 153(10): 1971-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18825484

RESUMO

A potyvirus was isolated from Brugmansia suaveolens showing leaf mottling and tentatively named Brugmansia suaveolens mottle virus (BsMoV). The virus (isolate Bs-Campinas) could infect some solanaceous plants and two Chenopodium species, and was transmitted by aphids. Symptomatic leaves contained flexuous particles and cylindrical inclusions. RT-PCR amplification using potyvirus universal primers produced a DNA fragment of 1851 nt (3' terminal genomic region), which shared 71% nucleotide identity with Pepper mottle virus, the best-matched potyvirus sequence. Since this identity value is below the threshold currently used to discriminate Potyvirus species, Brugmansia suaveolens mottle virus most likely represents a new Potyvirus species.


Assuntos
Doenças das Plantas/virologia , Potyvirus/classificação , Solanaceae/virologia , Animais , Afídeos/virologia , Brasil , Vetores de Doenças , Dados de Sequência Molecular , Folhas de Planta/virologia , Potyvirus/genética , Potyvirus/isolamento & purificação , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico
12.
Mol Biol Cell ; 10(10): 3331-43, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10512870

RESUMO

Fission yeast rad22(+), a homologue of budding yeast RAD52, encodes a double-strand break repair component, which is dispensable for proliferation. We, however, have recently obtained a cell division cycle mutant with a temperature-sensitive allele of rad22(+), designated rad22-H6, which resulted from a point mutation in the conserved coding sequence leading to one amino acid alteration. We have subsequently isolated rad22(+) and its novel homologue rti1(+) as multicopy suppressors of this mutant. rti1(+) suppresses all the defects of cells lacking rad22(+). Mating type switch-inactive heterothallic cells lacking either rad22(+) or rti1(+) are viable, but those lacking both genes are inviable and arrest proliferation with a cell division cycle phenotype. At the nonpermissive temperature, a synchronous culture of rad22-H6 cells performs DNA synthesis without delay and arrests with chromosomes seemingly intact and replication completed and with a high level of tyrosine-phosphorylated Cdc2. However, rad22-H6 cells show a typical S phase arrest phenotype if combined with the rad1-1 checkpoint mutation. rad22(+) genetically interacts with rad11(+), which encodes the large subunit of replication protein A. Deletion of rad22(+)/rti1(+) or the presence of rad22-H6 mutation decreases the restriction temperature of rad11-A1 cells by 4-6 degrees C and leads to cell cycle arrest with chromosomes incompletely replicated. Thus, in fission yeast a double-strand break repair component is required for a certain step of chromosome replication unlinked to repair, partly via interacting with replication protein A.


Assuntos
Reparo do DNA/genética , Proteínas Fúngicas/genética , Genes Fúngicos , Genes Fúngicos Tipo Acasalamento , Proteínas de Schizosaccharomyces pombe , Leveduras/genética , Sequência de Aminoácidos , Sequência de Bases , Bleomicina/farmacologia , Ciclo Celular/genética , Divisão Celular/genética , Clonagem Molecular , Proteínas de Ligação a DNA/genética , Proteínas Fúngicas/química , Regulação Fúngica da Expressão Gênica , Dados de Sequência Molecular , Mutação , Proteína de Replicação A , Fase S/genética , Supressão Genética , Temperatura
13.
Plant Dis ; 90(1): 114, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30786504

RESUMO

Three definitive and three tentative begomovirus species have been reported in tomato fields in Brazil according to a recent review (1). Extensive surveys have been conducted since the 1990s in solanaceous weeds and other crops planted close to tomato fields, but no tomato-infecting geminiviruses have been reported on those crops. During November 2003, leaves of one chili pepper plant "dedo-de-moça" (Capsicum baccatum var. pendulum) showing symptoms of yellow mosaic and leaf distortion were collected in Petrolina de Goiás (Goiás State). Serological analyses were carried out with polyclonal antisera produced in our laboratory against the following viruses: Potato virus Y (PVY), Pepper yellow mosaic virus (PepYMV), Tomato spotted wilt virus (TSWV), Tomato chlorotic spot virus (TCSV), Groundnut ringspot virus (GRSV), and Chrysanthemum stem necrosis virus (CSNV). Serological data showed that the plant was not infected with any of these viruses. A begomovirus-specific DNA-A fragment of 1.3 kb was amplified by polymerase chain reaction (PCR) from the analyzed plant. The fragment shared 98% identity to the partial coat protein coding region (CP), 94% to the intergenic region (IR), and 95% to the partial AC1 coding region of Tomato severe rugose virus (ToSRV) (GenBank Accession No. AY029750). Total DNA from the original infected plant was used to biolistically inoculate healthy plants of C. annuum and C. baccatum var. pendulum. Four resulting symptomatic plants, two from C. annuum and two from C. baccatum, were tested using PCR for begomovirus, and the nucleotide sequence of the amplified fragment confirmed they were infected with ToSRV. Whitefly inoculation of C. annuum, C. baccatum, and tomato was also performed, and all plants expressing symptoms were confirmed to be infected with ToSRV by sequencing a begomovirus-specific amplified fragment. Cloning of the complete DNA-A was achieved by using TempliPhi (Amersham Biosciences, Piscataway, NJ) amplification and digestion with a single cutting restriction endonuclease (2). Sequencing of several clones showed that the complete DNA-A (GenBank Accession No. DQ207749) was 97% identical to ToSRV, confirming the results of the previous PCR analysis. The deduced amino acid sequences showed identities of 97% to the CP, 95% to AC1, 96% to AC2, 96% to AC3, and 88% to AC4 of ToSRV. Although begomoviruses have not yet been causing any significant losses in chili pepper in Brazil, they may be of potential importance. Moreover, chili pepper, a plant commonly found in gardens throughout the country, may serve as an alternate host in tomato-producing areas. To our knowledge, this is the first report of a begomovirus infecting chili pepper in Brazil. References: (1) C. M. Fauquet et al. Arch. Virol. 148:405, 2003. (2). A. K. Inoue-Nagata et al. J Virol Methods 116:209, 2004.

14.
Oncogene ; 8(8): 2113-8, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8336937

RESUMO

A new gene encoding a cyclin-like protein has been isolated from a rat fibroblast cDNA library by cross-hybridization with a mixture of c-src family proto-oncogene kinase domains as a probe. This putative cyclin, called cyclin G, contains a typical cyclin box at the N-terminus but no apparent 'destruction box' or 'PEST' sequence. Interestingly, in its C-terminus region, it has a sequence homologous with a tyrosine phosphorylation site of the epidermal growth factor receptor. Although this cyclin is phylogenetically related to HCS26 of Saccharomyces cerevisiae, it most resembles Cig1, a B-type cyclin, of Schizosaccharomyces pombe, which has been suggested to act at the G1/S phase of the cell cycle. Cyclin G mRNA is induced within 3 h after growth stimulation and remains elevated with no apparent cell cycle dependency, indicating its close association with growth stimuli but not with the cell cycle.


Assuntos
Ciclinas/química , Proteínas Fúngicas/química , Schizosaccharomyces/química , Sequência de Aminoácidos , Animais , Sequência de Bases , Células Cultivadas , Ciclina G , Ciclina G1 , Ciclinas/genética , DNA/isolamento & purificação , Humanos , Dados de Sequência Molecular , Filogenia , Proto-Oncogene Mas , RNA Mensageiro/análise , Ratos , Homologia de Sequência de Aminoácidos
15.
Methods Find Exp Clin Pharmacol ; 27(5): 323-6, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16082420

RESUMO

We have developed a new enzyme-linked immunosorbent assay (ELISA) for the determination of cardiac myosin light chain I (MLI) in human serum. The detection range of ELISA was between 1 and 50 ng/ml, and serial dilutions of human serum showed good linearity. The recovery of different concentrations of cardiac MLI ranged from 87.5% to 100.0%. The intra-assay (n=5) and inter-assay (n=5) showed good results (C.V.<10%). The cross-reactivity with skeletal-myosin light chain (ML) was rather high, but was negligible with other myosin light chains. The concentrations of cardiac MLI in human serum determined by ELISA were similar to those determined by immunoradiometric assay (IRMA). The total assay time and sample volume required for ELISA were approx. 2 h and 25 microl, respectively, while those for IRMA are approx. 24 h and 100 microl. Our novel ELISA method therefore has significant advantages for clinical analysis.


Assuntos
Cadeias Leves de Miosina/análise , Anticorpos Monoclonais , Especificidade de Anticorpos , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Peroxidase do Rábano Silvestre/química , Humanos , Infarto do Miocárdio/metabolismo , Reprodutibilidade dos Testes
16.
Hum Gene Ther ; 10(12): 1975-82, 1999 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-10466631

RESUMO

For gene therapy of human malignant glioma, we adopted positively charged multilamellar liposomes entrapping the human interferon beta (hIFN-beta) gene. One week after the transplantation of human malignant glioma U251-SP cells to produce glioma in nude mouse brain, the liposomes entrapping the gene (500 ng of DNA per 25 nmol of lipids per 2 microl) were injected into the same site of the cell transplantation once every second day for a total of five injections; and by this means the tumor completely disappeared. To confirm the antiproliferative effect of hIFN-beta, we performed an in vitro study using a plasmid containing a secretion signal sequence-deleted hIFN-beta gene and one containing the hIFN-beta gene inserted in reverse. In both cases, there was no hIFN-beta release into the medium and no growth inhibition effect. On addition of anti-hIFN-beta antibody to the medium, the growth inhibition effect was abolished. As this cell line expresses IFN-alpha/beta receptor, the hIFN-beta produced in the transfected cells could be released and acted in a paracrine manner. For 120 days the body weight change of normal mice treated by the same procedure as used in the curing experiment was not significant among the groups injected with empty liposomes, plasmid only, and liposomes entrapping the gene. In all of these three groups, death, abnormal behavior, and significant histological changes were not observed.


Assuntos
Neoplasias Encefálicas/terapia , Terapia Genética/métodos , Glioma/terapia , Interferon beta/administração & dosagem , Animais , Cátions , Linhagem Celular , Portadores de Fármacos , Humanos , Interferon beta/genética , Lipossomos , Camundongos , Camundongos Nus , Plasmídeos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
17.
Gene ; 7(2): 153-71, 1979 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-229056

RESUMO

The effect of drugs which inhibit DNA gyrase, including nalidixic acid, oxolinic acid and coumerycin, on transcription of Escherichia coli bacteria, phage and plasmid genomes was studied. Quantitative estimates of the synthesis of RNA under drug-treatment conditions showed that synthesis of many RNA species, including trp mRNA, was subject to inhibiton by the drug. Transcription directed by the lambda promoter pR was selectively less sensitive to the drug action than transcription initiated at the lambda promoter pL. Evidence was obtained showing that diminished transcription resulted from less frequent RNA chain initiation rather than a premature arrest of the chain elongation. Inhibiton of transcription by these DNA gyrase inhibitors was observed even in the absence of DNA replication. The inhibition by oxolinic acid or coumerycin was not observed in an E. coli strain bearing a nalAr mutation or a cour mutation, respectively. The reduction of trp mRNA synthesis in oxolinic acid-treated cells cannot be attributed to the increase in the rate of nascent mRNA degradation. These results indicate that DNA gyrase is generally required for intracellular RNA synthesis, and suggest that the supercoiling of DNA by this winding enzyme enhances the initiation of transcription.


Assuntos
DNA Topoisomerases Tipo II/metabolismo , Escherichia coli/metabolismo , Transcrição Gênica , Bacteriófago lambda/metabolismo , Ácido Nalidíxico/farmacologia , Plasmídeos , RNA Bacteriano/biossíntese , RNA Mensageiro/biossíntese , RNA Viral/biossíntese , Inibidores da Topoisomerase II
18.
Gene ; 13(2): 173-84, 1981 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6263758

RESUMO

The superhelical density of pMT plasmid DNA in Escherichia coli cells was measured as a function of the transcriptional activity, which was reduced by treatment with coumermycin or oxolinic acid. Superhelicity was assayed by agarose gel electrophoresis of DNA extracted from cells gently lysed by sarkosyl. Coumermycin treatment reduced the proportion of supercoiled plasmid DNA in concert with a decrease in the rate of plasmid-coded synthesis of trp mRNA, implying a correlation between supercoiling of DNA and its suitability for transcription. On the other hand, the oxolinic acid-induced loss of supercoiled plasmid DNA was relatively small, while concomitant inhibition of trp mRNA synthesis was very severe. Treatment of the cells with these two drugs never removed all of supertwists from the pMT plasmids carried.


Assuntos
DNA Topoisomerases Tipo II/fisiologia , DNA Super-Helicoidal/genética , Transcrição Gênica , Aminocumarinas , Colífagos/genética , Cumarínicos/farmacologia , Escherichia coli/genética , Conformação de Ácido Nucleico , Ácido Oxolínico/farmacologia , Plasmídeos , Pirróis/farmacologia , Moldes Genéticos , Inibidores da Topoisomerase II , Transcrição Gênica/efeitos dos fármacos
19.
FEBS Lett ; 318(3): 331-4, 1993 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-8440392

RESUMO

In mammalian cells, p34cdc2 kinase undergoes phosphorylation at threonine-14, tyrosine-15 and threonine-161 in the S and G2 phases of the cell cycle. At the onset of mitosis, the kinase becomes dephosphorylated at threonine-14 and tyrosine-15, resulting in activation. Cdc25 phosphatase has been shown to dephosphorylate tyrosine-15 in vitro, but whether it also does at threonine-14 remains unclear. In this study, we have found that human cdc25B phosphatase dephosphorylates both threonine-14 and tyrosine-15 but not threonine-161.


Assuntos
Proteína Quinase CDC2/metabolismo , Proteínas/metabolismo , Treonina/metabolismo , Tirosina/metabolismo , Escherichia coli/metabolismo , Células HeLa/metabolismo , Humanos , Mitose , Mapeamento de Peptídeos , Fosforilação , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Fosfatases cdc25
20.
J Immunol Methods ; 173(2): 157-64, 1994 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-8046250

RESUMO

We developed a simple and sensitive enzyme-linked immunosorbent assay (ELISA) for human pulmonary surfactant protein D (SP-D). Human SP-D was purified from bronchoalveolar lavage fluids of patients with pulmonary alveolar proteinosis. Nine monoclonal antibodies (MAbs) were established from BALB/c mice immunized with the purified human SP-D. All MAbs were directed to either 43 kDa SP-D contained in lung lavage fluids of patients with pulmonary alveolar proteinosis or in amniotic fluids from healthy normal pregnancies. The ELISA is based on a sandwich method using two MAbs, 6B2 and 7C6. Cross-reactivity to human SP-A or rat SP-D was evaluated as below 0.6%. The recovery of different concentrations of SP-D ranged from 94.4% to 111.2%, and serial dilutions of amniotic fluids showed good linearity. SP-D concentrations in 21 amniotic fluids from normal pregnancies were measured by the ELISA. The mean concentration in amniotic fluids from pregnancies in the third trimester was significantly higher than that from earlier stages of gestation (p < 0.001), indicating that this ELISA may be applicable for prediction of fetal lung maturity.


Assuntos
Anticorpos Monoclonais/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Glicoproteínas/análise , Pulmão/embriologia , Surfactantes Pulmonares/análise , Líquido Amniótico/química , Animais , Anticorpos Monoclonais/biossíntese , Western Blotting , Líquido da Lavagem Broncoalveolar/química , Eletroforese em Gel de Poliacrilamida , Feminino , Maturidade dos Órgãos Fetais , Glicoproteínas/imunologia , Glicoproteínas/isolamento & purificação , Humanos , Hibridomas , Camundongos , Camundongos Endogâmicos BALB C , Gravidez , Proteinose Alveolar Pulmonar/metabolismo , Proteína D Associada a Surfactante Pulmonar , Surfactantes Pulmonares/imunologia , Surfactantes Pulmonares/isolamento & purificação , Sensibilidade e Especificidade
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