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1.
J Appl Microbiol ; 127(4): 1255-1269, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31309647

RESUMO

AIMS: To determine the seasonal occurrence and diversity of norovirus (NoV) and human adenovirus (HAdV) in groundwater from sinkholes, and brackish water used for recreational activities in the karst aquifer of the Yucatan Peninsula, Mexico. METHODS AND RESULTS: Hollow fibre ultrafiltration was used to concentrate viruses and standard plaque assay methods were used to enumerate somatic and F+ specific coliphages as viral indicators. Real-time quantitative polymerase chain reaction assays were used to estimate the number of genome copies for NoV strains GI, and GII, and HAdVs. The predominant NoV genotypes and HAdV serotypes were identified by comparative sequence analysis. Somatic and male F+ specific coliphages were detected at concentrations up to 94 and 60 plaque-forming units per 100 ml respectively. The NoV genogroup I (GI) was associated with 50% of the sampled sites during the rainy season only, at concentrations ranging from 120 to 1600 genome copies per litre (GC l-1 ). The NoV genogroup II (GII) was detected in 30 and 40% of the sampled sites during the rainy and dry seasons, respectively, at concentrations ranging from 10 to 290 GC l-1 . During the rainy and dry seasons, HAdVs were detected in 20% of the sites, at concentrations ranging from 24 to 690 GC l-1 . Identification of viral types revealed the presence of NoV GI.2, GII.Pe, GII.P16 and GII.P17, and HAdV F serotypes 40 and 41. CONCLUSIONS: These findings demonstrate that NoVs and HAdVs are prevalent as virus contaminants in the karst aquifer, representing potential health risks particularly during the rainy season, in one of the most important areas used for tourism in Mexico. SIGNIFICANCE AND IMPACT OF THE STUDY: This is one of the few studies conducted in karst aquifers that provide a foundational baseline of the distribution, concentrations and diversity of NoVs and HadVs in these particular environments.


Assuntos
Adenovírus Humanos , Água Subterrânea/virologia , Norovirus , Adenovírus Humanos/classificação , Adenovírus Humanos/genética , Adenovírus Humanos/isolamento & purificação , México , Norovirus/classificação , Norovirus/genética , Norovirus/isolamento & purificação , Microbiologia da Água
2.
Int J Tuberc Lung Dis ; 22(11): 1383-1386, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30355421

RESUMO

Pomalidomide, previously used to treat multiple myeloma, has been reported to cause acute pulmonary toxicity that improves with drug discontinuation. We present a case of delayed pneumonitis with persistent fibrosis associated with pomalidomide. A 61-year-old male treated with pomalidomide and corticosteroids presented with acute on chronic dyspnea, profound hypoxemia, and ground glass opacities on computerized tomographic imaging. Corticosteroid taper and discontinuation of pomalidomide resulted in clinical improvement, but with substantial residual pulmonary fibrosis. Given the temporal improvement, but not resolution, following discontinuation of an agent with an established propensity for lung injury, we attribute this presentation to pomalidomide toxicity.


Assuntos
Antineoplásicos/efeitos adversos , Pulmão/efeitos dos fármacos , Mieloma Múltiplo/tratamento farmacológico , Pneumonia/induzido quimicamente , Fibrose Pulmonar/induzido quimicamente , Talidomida/análogos & derivados , Humanos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Pneumonia/diagnóstico por imagem , Fibrose Pulmonar/diagnóstico por imagem , Talidomida/efeitos adversos , Tomografia Computadorizada por Raios X
3.
Virus Res ; 169(1): 296-300, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22841489

RESUMO

The complete genome of 2780 bases was amplified using rolling circle amplification, and cloned, and sequenced for two distinct strains of the monopartite begomovirus Tomato leaf curl Sudan virus (ToLCSDV). The two strains shared 86-91% identity with the previously described ToLCSDV from the Nile Basin, and 90-91% identity with one another. One strain was cloned from symptomatic tomato plants from Tihamah (ToLCSDV-YE[YE:Tih:05]) while the other was cloned from symptomatic tobacco plants collected from Wadi Hadramaut (ToLCSDV-YE[YE:Had:89]). A distinct full-length betasatellite molecule (1352 bases) was cloned from the respective field-infected tomato and tobacco plants. Agro-inoculation of tomato and Nicotiana benthamiana plants with cloned partial tandem repeats of ToLCSDV-YE[YE:Tih11:05]) and the associated betasatellite, Tomato leaf curl Yemen betasatellite (ToLCYEB-[Tih:tom:137:05]), resulted in the reproduction of leaf curl disease symptoms in test plants like those observed in the field-infected plants. The betasatellite contributed to symptom severity in N. benthamiana test plants when it was co-inoculated with ToLCSDV-YE, compared to the milder symptoms that were observed in tobacco plants infected with the helper virus alone.


Assuntos
Begomovirus/classificação , Begomovirus/genética , DNA Satélite/genética , DNA Viral/genética , Doenças das Plantas/virologia , Solanaceae/virologia , Arábia , Begomovirus/isolamento & purificação , Análise por Conglomerados , Genoma Viral , Solanum lycopersicum/virologia , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Nicotiana/virologia
4.
J Exp Bot ; 63(3): 1271-83, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22090435

RESUMO

The Green Revolution dwarfing genes, Rht-B1b and Rht-D1b, encode mutant forms of DELLA proteins and are present in most modern wheat varieties. DELLA proteins have been implicated in the response to biotic stress in the model plant, Arabidopsis thaliana. Using defined wheat Rht near-isogenic lines and barley Sln1 gain of function (GoF) and loss of function (LoF) lines, the role of DELLA in response to biotic stress was investigated in pathosystems representing contrasting trophic styles (biotrophic, hemibiotrophic, and necrotrophic). GoF mutant alleles in wheat and barley confer a resistance trade-off with increased susceptibility to biotrophic pathogens and increased resistance to necrotrophic pathogens whilst the converse was conferred by a LoF mutant allele. The polyploid nature of the wheat genome buffered the effect of single Rht GoF mutations relative to barley (diploid), particularly in respect of increased susceptibility to biotrophic pathogens. A role for DELLA in controlling cell death responses is proposed. Similar to Arabidopsis, a resistance trade-off to pathogens with contrasting pathogenic lifestyles has been identified in monocotyledonous cereal species. Appreciation of the pleiotropic role of DELLA in biotic stress responses in cereals has implications for plant breeding.


Assuntos
Resistência à Doença/fisiologia , Hordeum/metabolismo , Triticum/metabolismo , Ascomicetos/patogenicidade , Resistência à Doença/genética , Genes de Plantas/genética , Genes de Plantas/fisiologia , Hordeum/genética , Hordeum/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Triticum/genética , Triticum/microbiologia
5.
J Gen Virol ; 92(Pt 3): 706-17, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21084498

RESUMO

The Oman strain of Tomato yellow leaf curl virus (TYLCV-OM) and its associated betasatellite, an isolate of Tomato leaf curl betasatellite (ToLCB), were previously reported from Oman. Here we report the isolation of a second, previously undescribed, begomovirus [Tomato leaf curl Oman virus (ToLCOMV)] and an alphasatellite from that same plant sample. This alphasatellite is closely related (90 % shared nucleotide identity) to an unusual DNA-2-type Ageratum yellow vein Singapore alphasatellite (AYVSGA), thus far identified only in Singapore. ToLCOMV was found to have a recombinant genome comprising sequences derived from two extant parents, TYLCV-OM, which is indigenous to Oman, and Papaya leaf curl virus from the Indian subcontinent. All possible combinations of ToLCOMV, TYLCV-OM, ToLCB and AYVSGA were used to agro-inoculate tomato and Nicotiana benthamiana. Infection with ToLCOMV yielded mild leaf-curl symptoms in both hosts; however, plants inoculated with TYLCV-OM developed more severe symptoms. Plants infected with ToLCB in the presence of either helper begomovirus resulted in more severe symptoms. Surprisingly, symptoms in N. benthamiana infected with the alphasatellite together with either of the helper viruses and the betasatellite were attenuated and betasatellite DNA accumulation was substantially reduced. However, in the latter plants no concomitant reduction in the accumulation of helper virus DNA was observed. This is the first example of an attenuation of begomovirus-betasatellite symptoms by this unusual class of alphasatellites. This observation suggests that some DNA-2 alphasatellites encode a pathogenicity determinant that may modulate begomovirus-betasatellite infection by reducing betasatellite DNA accumulation.


Assuntos
Begomovirus/genética , Begomovirus/patogenicidade , DNA Satélite/genética , Doenças das Plantas/virologia , Solanum lycopersicum/virologia , Begomovirus/isolamento & purificação , Dados de Sequência Molecular , Omã , Filogenia , Análise de Sequência de DNA , Homologia de Sequência , Nicotiana/virologia
6.
Arch Virol ; 155(10): 1571-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20574644

RESUMO

Rhynchosia minima (L.) DC. (Fabaceae) plants exhibiting bright golden mosaic symptoms were previously associated with begomovirus infection in Yucatan, México [1]. To characterize the begomovirus infecting these plants, the complete bipartite genome was cloned and sequenced. Sequence comparisons indicated that the virus was distinct from all other begomoviruses known to date, including those previously identified from symptomatic R. minima, and the name Rhynchosia yellow mosaic Yucatan virus (RhYMYuV) is proposed. Pairwise comparisons indicated that RhYMYuV DNA-A [2,597 nt, (EU021216)] and DNA-B [2,542 nt, (FJ792608)] components shared the highest nt sequence identity with Cabbage leaf curl virus (CaLCuV), 87% for component A and 71% for component B. Phylogenetic analysis indicated that both components of RhYMYuV are most closely related to other New World begomoviruses, having as closest relatives immediate outliers to the major Squash leaf curl virus (SLCV) clade. Recombination analysis of the RhYMYuV genome indicated that the DNA-A component has arisen through intermolecular recombination. R. minima plants inoculated with the monomeric clones developed a bright yellow mosaic similar to symptoms observed in naturally infected plants, confirming that the clones were infectious. Nicotiana benthamiana plants biolistically inoculated with monomeric clones developed curling and chlorosis in the newly emerging leaves. RhYMYuV was also detected in symptomatic Desmodium sect. Scorpiurus Benth. (Fabaceae) that were collected near the RhYMYuV-infected plants.


Assuntos
Begomovirus/isolamento & purificação , Fabaceae/virologia , Doenças das Plantas/virologia , Begomovirus/classificação , Begomovirus/genética , Clonagem Molecular , Análise por Conglomerados , DNA Viral/química , DNA Viral/genética , Evolução Molecular , Genoma Viral , México , Dados de Sequência Molecular , Filogenia , Recombinação Genética , Análise de Sequência de DNA , Homologia de Sequência , Nicotiana/virologia
7.
Virus Genes ; 39(3): 387-95, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19768650

RESUMO

Partial genome segments of a begomovirus were previously amplified from Wissadula amplissima exhibiting yellow-mosaic and leaf-curl symptoms in the parish of St. Thomas, Jamaica and this isolate assigned to a tentative begomovirus species, Wissadula golden mosaic St. Thomas virus. To clone the complete genome of this isolate of Wissadula golden mosaic St. Thomas virus, abutting primers were designed to PCR amplify its full-length DNA-A and DNA-B components. Sequence analysis of the complete begomovirus genome obtained, confirmed that it belongs to a distinct begomovirus species and this isolate was named Wissadula golden mosaic St. Thomas virus-[Jamaica:Albion:2005] (WGMSTV-[JM:Alb:05]). The genome of WGMSTV-[JM:Alb:05] is organized similar to that of other bipartite Western Hemisphere begomoviruses. Phylogenetic analyses placed the genome components of WGMSTV-[JM:Alb:05] in the Abutilon mosaic virus clade and showed that the DNA-A component is most closely related to four begomovirus species from Cuba, Tobacco leaf curl Cuba virus, Tobacco leaf rugose virus, Tobacco mottle leaf curl virus, and Tomato yellow distortion leaf virus. The putative Rep-binding-site motif in the common region of WGMSTV-[JM:Alb:05] was observed to be identical to that of Chino del tomate virus-Tomato [Mexico:Sinaloa:1983], Sida yellow mosaic Yucatan virus-[Mexico:Yucatan:2005], and Tomato leaf curl Sinaloa virus-[Nicaragua:Santa Lucia], suggesting that WGMSTV-[JM:Alb:05] is capable of forming viable pseudo-recombinants with these begomoviruses, but not with other members of the Abutilon mosaic virus clade. Biolistic inoculation of test plant species with partial dimers of the WGMSTV-[JM:Alb:05] DNA-A and DNA-B components showed that the virus was infectious to Nicotiana benthamiana and W. amplissima and the cultivated species Phaseolus vulgaris (kidney bean) and Lycopersicon esculentum (tomato). Infected W. amplissima plants developed symptoms similar to symptoms observed under field conditions, confirming that this virus is a causal agent of Wissadula yellow mosaic disease in W. amplissima.


Assuntos
Begomovirus/classificação , Begomovirus/crescimento & desenvolvimento , Malvaceae/virologia , Sequência de Bases , Begomovirus/genética , Begomovirus/isolamento & purificação , Análise por Conglomerados , Primers do DNA/genética , DNA Viral/química , DNA Viral/genética , Ordem dos Genes , Genes Virais , Genoma Viral , Jamaica , Solanum lycopersicum/virologia , Dados de Sequência Molecular , Phaseolus/virologia , Filogenia , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA , Homologia de Sequência , Sintenia , Nicotiana/virologia
8.
Virus Res ; 109(1): 19-32, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15826909

RESUMO

Cotton leaf curl Gezira virus (CLCuGV), a species of the genus Begomovirus (family Geminiviridae), was recently cloned from cotton, okra, and Sida alba plants exhibiting leaf-curling and vein-thickening symptoms in Sudan. Here, we describe a previously unknown lineage of single-stranded DNA satellite (satDNA) molecules, which are associated with CLCuGV, and are required for development of characteristic disease symptoms. Co-inoculation of cotton and Nicotiana benthamiana plants with satDNAs cloned from cotton, okra, and S. alba, together with CLCuGV as the 'helper virus' resulted in the development of characteristic leaf-curling and vein-thickening symptoms in both hosts. An anatomical study of symptomatic, virus-infected cotton leaves revealed that spongy parenchyma cells had developed instead of collenchyma cells at the sites of vein thickening. Phylogenetically, the CLCuGV-associated satDNAs from Sudan, together with their closest relatives from Egypt, form a new satDNA lineage comprising only satDNAs from the Upper and Lower Nile Basins. Analysis of satellites and their helper virus sequences identified a predicted REP-binding site consisting of the directly repeated sequence, 'CGGTACTCA', and an inverted repeated sequence, 'TGAGTACCG', which occur in the context of a 17-nucleotide motif. The conserved REP-binding motif identified herein, together with strict geographic isolation, and apparent host-restriction, may be the collective hallmark of these new satDNA-begomovirus lineages, extant in the Nile Basin.


Assuntos
DNA de Cadeia Simples/isolamento & purificação , DNA Viral/genética , DNA Viral/isolamento & purificação , Geminiviridae/genética , Geminiviridae/isolamento & purificação , Sítios de Ligação/genética , Sequência Conservada , DNA de Cadeia Simples/química , DNA de Cadeia Simples/classificação , DNA de Cadeia Simples/genética , DNA Viral/química , Egito , Gossypium/virologia , Dados de Sequência Molecular , Filogenia , Doenças das Plantas/virologia , Sequências Repetitivas de Ácido Nucleico , Análise de Sequência de DNA , Homologia de Sequência , Sudão , Nicotiana/virologia
9.
Phytopathology ; 95(10): 1217-24, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18943475

RESUMO

ABSTRACT Three isolates of the bipartite begomovirus Pepper golden mosaic virus (PepGMV) were characterized for genomic and biological properties. The complete nucleotide sequences of the DNA-A and DNA-B components were determined from infectious clones of PepGMV-Serrano (PepGMV-Ser), PepGMV-Mosaic (PepGMV-Mo), and PepGMV-Distortion (PepGMV-D). Nucleotide sequence identity among PepGMV components ranged from 91 to 96% for DNA-A and from 84 to 99% for DNA-B, with each PepGMV component most closely related to the corresponding component of Cabbage leaf curl virus (CaLCV). However, phylogenetic relationships among begomovirus components were incongruent because DNA-A of PepGMV and CaLCV share an inferred evolutionary history distinct from that of DNA-B. The cloned components of PepGMV-Ser, -Mo, and -D were infectious by biolistic inoculation to pepper but differed in symptom expression: PepGMV-Ser exhibited a bright golden mosaic, PepGMV-Mo produced a yellow-green mosaic, and PepGMV-D caused only a mild mosaic and foliar distortion followed by a "recovery" phenotype in which leaves developing after initial symptom expression appeared normal. Differences in symptoms also were observed on tomato, tobacco, and Datura stramonium. Progeny virus derived from clones of PepGMV-Ser and -Mo were transmitted from pepper to pepper by the B biotype of Bemisia tabaci; progeny virus derived from PepGMV-D clones was not transmissible by the B biotype. Reassortant genomes derived from heterologous DNA components of the three isolates were infectious in all possible pairwise combinations, with symptom phenotype in pepper determined by the DNA-B component. Collectively, these results indicate that the three virus isolates examined may be considered distinct strains of PepGMV that have the capacity to exchange genetic material.

10.
Am J Physiol Gastrointest Liver Physiol ; 287(1): G178-91, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15016615

RESUMO

Upregulation of CGRP-immunoreactive (IR) primary afferent nerve fibers accompanied by mastocytosis is characteristic for the Schistosoma mansoni-infected murine ileum. These mucosal mast cells (MMC) and CGRP-IR fibers, which originate from dorsal root (DRG) and nodose ganglia, are found in close apposition. We examined interactions between primary cultured MMC and CGRP-IR DRG neurons in vitro by confocal recording of intracellular Ca(2+) concentration ([Ca(2+)](i)). The degranulatory EC(50) for the mast cell secretagogue compound 48/80 (C48/80; 10 microg/ml) and the neuropeptides CGRP (2.10(-8) M) and substance P (SP; 3.10(-8) M) were determined by measurement of extracellular release of the granule chymase, mouse mast cell protease-1. Application of C48/80 (10 microg/ml) and CGRP and SP (both 10(-7) M) to Fluo-4-loaded MMC induced a transient rise in [Ca(2+)](i) after a lag time, indicative of mast cell degranulation and/or secretion. The CGRP response could be completely blocked by pertussis toxin (2 microg/ml), indicating involvement of G(i) proteins. Application of MMC juice, obtained by C48/80 degranulation of MMC, to Fluo-4-loaded DRG neurons induced in all neurons a rise in [Ca(2+)](i), indicative of activation. Degranulation of MMC by C48/80 in culture dishes containing Fluo-4-loaded DRG neurons also caused activation of the DRG neurons. In conclusion, these results demonstrate a bidirectional cross-talk between cultured MMC and CGRP-IR DRG neurons in vitro. This indicates that such a communication may be the functional relevance for the close apposition between MMC and CGRP-IR nerve fibers in vivo.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Degranulação Celular/fisiologia , Gânglios Espinais/fisiologia , Mucosa Intestinal/fisiologia , Mastócitos/fisiologia , Neurônios/fisiologia , Animais , Líquidos Corporais/fisiologia , Peptídeo Relacionado com Gene de Calcitonina/farmacologia , Cálcio/metabolismo , Células Cultivadas , Gânglios Espinais/citologia , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Membranas Intracelulares/metabolismo , Masculino , Mastócitos/metabolismo , Camundongos , Concentração Osmolar , Substância P/farmacologia , p-Metoxi-N-metilfenetilamina/farmacologia
11.
J Helminthol ; 77(2): 155-61, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12756069

RESUMO

Mucosal mast cells (MMC) play an important role in the immune response against selected species of intestinal nematode. The kinetics with which different strains of inbred mice resolve infection with Trichinella spiralis correlates with their ability to mount MMC responses in the intestinal mucosa. Homologues of MMC that express and constitutively secrete abundant amounts of the granule chymase, mouse mast cell protease-1 (mMCP-1), can be generated in vitro from bone marrow cultures supplemented with interleukins-3 and -9, stem cell factor and transforming growth factor-beta1. Using the enhanced growth characteristics of these MMC homologues, a novel limiting dilution assay for mast cell precursor (MCp) frequency has been developed. The assay is highly specific, in that cultures containing mast cells are identified with mMCP-1 specific antibody, and almost three-fold more sensitive than previously published systems. MCp frequencies were compared in BALB/c and C57/BL10 strains of mice that, respectively, respond rapidly and slowly to infection with T. spiralis. MCp frequency (1/378 bone marrow cells) was significantly greater in BALB/c than C57/BL10 mice (frequency: 1/751). Similarly the rate of growth of MMC homologues and the production of mMCP-1 was significantly greater in BALB/c than in C57/BL10 bone marrow cultures.


Assuntos
Enteropatias Parasitárias/imunologia , Mucosa Intestinal/imunologia , Mastócitos/imunologia , Trichinella spiralis , Triquinelose/imunologia , Animais , Anticorpos/análise , Células da Medula Óssea , Diferenciação Celular , Células Cultivadas , Quimases , Meios de Cultura , Imunofluorescência , Interleucina-3 , Interleucina-9 , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Serina Endopeptidases/imunologia , Especificidade da Espécie , Fator de Células-Tronco , Fator de Crescimento Transformador beta
12.
Clin Exp Allergy ; 33(1): 132-46, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12534561

RESUMO

BACKGROUND: The mucosal mast cell (MMC) granule-specific beta-chymase, mouse mast cell protease-1 (mMCP-1), is released systemically into the bloodstream early in nematode infection before parasite-specific IgE responses develop and TGF-beta1 induces constitutive release of mMCP-1 by homologues of MMC in vitro. Intraepithelial MMC may also express the chemokine CCL2 (monocyte chemotactic protein-1) during nematode infection but the expression of this chemokine by MMC homologues has not been investigated. OBJECTIVE: To investigate the expression and to compare the mechanisms of constitutive release of the chymase, mMCP-1, and the chemokine, CCL2. METHODS: MMC homologues were generated by culturing bone marrow cells in the presence of TGF-beta1, IL-3, IL-9 and stem cell factor (SCF). The intracellular distribution of mMCP-1 and CCL2 was examined by confocal microscopy. The involvement of the Golgi complex and of protein synthesis in the constitutive release of mMCP-1 and CCL2 was investigated using the Golgi-disrupting agent brefeldin A and cycloheximide to block protein synthesis. Secreted analytes were quantified by ELISA. RESULTS: mMCP-1 colocalized with Golgi matrix protein 130 but was most abundant in the granules, whereas CCL2 was not found in the granules but appeared to be located uniquely in the Golgi complex. Extracellular release of mMCP-1 was significantly inhibited ( approximately 40%) by cycloheximide and by the Golgi-disrupting agent brefeldin A, indicating both continuous protein synthesis and transportation via the Golgi complex are required for optimal mMCP-1 secretion. A similar but more marked inhibitory effect with both compounds was demonstrated on the constitutive secretion of CCL2. CONCLUSION: The culture conditions that promote mMCP-1 expression and release by MMC homologues also promote the expression and release of CCL2. Constitutive release involves de novo protein synthesis and requires a functional Golgi complex, suggesting that similar mechanisms of extracellular secretion operate for both mediators.


Assuntos
Proteínas de Bactérias/metabolismo , Complexo de Golgi/química , Mastócitos/enzimologia , Proteínas de Membrana/metabolismo , Mucosa Respiratória/imunologia , Serina Endopeptidases/metabolismo , Animais , Apoptose , Células da Medula Óssea , Brefeldina A/farmacologia , Técnicas de Cultura de Células , Células Cultivadas , Quimases , Cicloeximida/farmacologia , Complexo de Golgi/efeitos dos fármacos , Masculino , Mastócitos/ultraestrutura , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Confocal , Inibidores da Síntese de Proteínas/farmacologia , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serina Endopeptidases/análise , Serina Endopeptidases/genética
13.
Mol Ecol ; 11(7): 1219-29, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12074729

RESUMO

During the 1990s, an epidemic of cassava mosaic virus disease caused major losses to cassava production in Uganda. Two factors associated with the epidemic were the occurrence of a novel recombinant begomovirus, EACMV-Ug, and unusually high populations of the whitefly vector, Bemisia tabaci. Here we present molecular evidence for the occurrence of two cassava-colonizing B. tabaci genotype clusters, Ug1 and Ug2, one of which, Ug2, can be consistently associated with the CMD epidemic in Uganda at the time of collection in 1997. By contrast, a second genotype cluster, Ug1, only occurred 'at' or 'ahead of' the epidemic 'front', sometimes in mixtures with Ug2. Comparison of mitochondrial cytochrome oxidase I gene sequences for Ug1 and Ug2 and well-studied B. tabaci reference populations indicated that the two Ugandan populations exhibited approximately 8% divergence, suggesting they represent distinct sub-Saharan African lineages. Neither Ugandan genotype cluster was identified as the widely distributed, polyphagous, and highly fecund B biotype of Old World origin, with which they both diverged by approximately 8%. Within genotype cluster divergence of Ug1 at 0.61 +/- 0.1% was twice that of Ug2 at 0.35 +/- 0.1%. Mismatch analysis suggested that Ug2 has undergone a recent population expansion and may be of nonUgandan origin, whereas Ug1 has diverged more slowly, and is likely to be an indigenous genotype cluster.


Assuntos
Surtos de Doenças , Geminiviridae/crescimento & desenvolvimento , Hemípteros/genética , Manihot/virologia , Doenças das Plantas/virologia , Animais , Sequência de Bases , DNA Mitocondrial/química , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/química , Complexo IV da Cadeia de Transporte de Elétrons/genética , Hemípteros/crescimento & desenvolvimento , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Uganda/epidemiologia
14.
Phytopathology ; 92(7): 734-42, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18943269

RESUMO

ABSTRACT Cucurbit leaf curl virus (CuLCV), a whitefly-transmitted geminivirus previously partially characterized from the southwestern United States and northern Mexico, was identified as a distinct bipartite begomovirus species. This virus has near sequence identity with the previously partially characterized Cucurbit leaf crumple virus from California. Experimental and natural host range studies indicated that CuLCV has a relatively broad host range within the family Cucurbitaceae and also infects bean and tobacco. The genome of an Arizona isolate, designated CuLCV-AZ, was cloned and completely sequenced. Cloned CuLCV-AZ DNA A and B components were infectious by biolistic inoculation to pumpkin and progeny virus was transmissible by the whitefly vector, Bemisia tabaci, thereby completing Koch's postulates. CuLCV-AZ DNA A shared highest nucleotide sequence identity with Squash leaf curl virus-R (SLCV-R), SLCV-E, and Bean calico mosaic virus (BCaMV) at 84, 83, and 80%, respectively. The CuLCV DNA B component shared highest nucleotide sequence identity with BCaMV, SLCV-R, and SLCV-E at 71, 70, and 68%, respectively. The cis-acting begomovirus replication specificity element, GGTGTCCTGGTG, in the CuLCV-AZ origin of replication is identical to that of SLCV-R, SLCV-E, and BCaMV, suggesting that reassortants among components of CuLCV-AZ and these begomoviruses may be possible. Reassortment experiments in pumpkin demonstrated that both reassortants of CuLCV-AZ and SLCV-E A and B components were viable. However, for CuLCV-AZ and SLCV-R, only one reassortant (SLCV-R DNA A/CuLCV-AZ DNA B) was viable on pumpkin, even though the cognate component pairs of both viruses infect pumpkin. These results demonstrate that reassortment among sympatric begomovirus species infecting cucurbits are possible, and that, if generated in nature, could result in begomoviruses bearing distinct biological properties.

15.
Nurs Outlook ; 49(4): 166-72, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11514788

RESUMO

This study describes the survey results of a national random sample of members of the Oncology Nursing Society who reported the greatest number of barriers to delivering a tobacco cessation intervention with their patients. Nurses who perceived the greatest number of barriers were more likely to be current smokers and to be young and were less likely to have an advanced degree, to be a nurse practitioner, or to have administrative responsibilities. Those with greater barriers were less likely to deliver tobacco cessation interventions.


Assuntos
Atitude do Pessoal de Saúde , Promoção da Saúde , Avaliação em Enfermagem , Enfermagem Oncológica , Aceitação pelo Paciente de Cuidados de Saúde , Abandono do Hábito de Fumar , Adulto , Idoso , Coleta de Dados , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Enfermagem Oncológica/educação , Estados Unidos
16.
Am J Respir Cell Mol Biol ; 24(2): 146-54, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11159048

RESUMO

We previously reported that mast cell tryptase is a potent mitogen for cultured airway smooth-muscle cells, but the early intracellular signals mediating this response are not known. In many cells, proliferative effects are mediated by a mitogen-activated protein kinase signaling pathway involving Raf-1, MAP kinase kinases (MEKs), and extracellular signal-regulated protein kinases (ERKs) 1 and 2. Therefore, we tested for tryptase-induced activation of ERK1 and 2 in cultured dog tracheal smooth-muscle cells. Tryptase, in nanomolar concentrations which potently stimulated DNA synthesis, increased dual phosphorylation of ERKs in cellular lysates as well as ERK2 kinase activity in immunoprecipitates. Pretreatment of cells with the MEK inhibitor PD098059 abolished tryptase-induced increases in DNA synthesis and attenuated increases in ERK2 activity. Irreversible inhibition of tryptase's proteolytic activity, using p-amidino phenylmethanesulfonyl fluoride, attenuated tryptase-induced increases in DNA synthesis and dual phosphorylation of ERKs by 76% and 40 to 60%, respectively. Tryptase also increased c-fos transcription as quantified in polymerase chain reactions. In concentrations that caused similar increases in DNA synthesis, tryptase and platelet-derived growth factor (PDGF-BB) increased ERK activity (and c-fos transcription) with markedly different kinetics, the tryptase-induced responses being slower in onset and more sustained. We conclude that tryptase-induced mitogenesis in airway smooth-muscle cells requires activation of ERK1 and 2; that these responses depend partially, but not completely, upon tryptase's properties as a protease; and that they are slower in onset and more sustained than those induced by PDGF-BB.


Assuntos
Mastócitos/enzimologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mitose/fisiologia , Músculo Liso/efeitos dos fármacos , Fluoreto de Fenilmetilsulfonil/análogos & derivados , Serina Endopeptidases/farmacologia , Animais , Western Blotting , DNA/metabolismo , Primers do DNA/química , Cães , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Humanos , MAP Quinase Quinase 1 , Proteína Quinase 3 Ativada por Mitógeno , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Músculo Liso/citologia , Músculo Liso/metabolismo , Fluoreto de Fenilmetilsulfonil/farmacologia , Fosforilação , Inibidores de Proteases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-fos/análise , Proteínas Proto-Oncogênicas c-fos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serina Endopeptidases/efeitos adversos , Fatores de Tempo , Traqueia/citologia , Traqueia/enzimologia , Triptases
17.
Oncol Nurs Forum ; 27(10): 1519-28, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11103372

RESUMO

PURPOSE/OBJECTIVES: To describe oncology nurses' attitudes, smoking behaviors, and involvement in tobacco-control policy and legislation. DESIGN: Descriptive, cross-sectional survey. SAMPLE: Responses from 1,508 (38% return) of 4,000 randomly selected members of the Oncology Nursing Society (ONS). The typical respondent was female, age 44, a staff nurse, had practiced as an oncology nurse for 12 years, and was certified as an OCN. METHODS: A mailed survey with specific questions about smoking status and the importance of nursing involvement in healthcare policy and legislation for tobacco control. MAIN RESEARCH CONCEPTS: Attitudes about tobacco-control policies and legislation; sociodemographic, professional, and institutional variables; and tobacco use. FINDINGS: The majority (85%) of members stated that nursing involvement in tobacco-control healthcare policy and legislation was important. More than 90% of respondents supported prevention of youth access to tobacco and providing information about health effects of tobacco and cessation. Seven percent (n = 106) were current smokers. Significantly fewer smokers valued involvement in tobacco-control activities. Respondents with personal experience of tobacco-related illnesses were more likely to value involvement in advocacy activities. Educational programs to prevent tobacco use among youth and to help patients stop smoking received the most support (80%). IMPLICATIONS FOR NURSING PRACTICE: This sample of ONS members strongly supported involvement in tobacco-control policies and legislation. Smoking was associated with more negative attitudes about the importance of actively engaging in tobacco control. These oncology nurses recognized the need for additional educational programs to prevent tobacco initiation by youth.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Enfermagem Oncológica , Prevenção do Hábito de Fumar , Fumar/psicologia , Adulto , Idoso , Estudos Transversais , Política de Saúde , Humanos , Pessoa de Meia-Idade , Fumar/legislação & jurisprudência , Abandono do Hábito de Fumar , Inquéritos e Questionários
18.
Dev Med Child Neurol ; 42(8): 525-30, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10981930

RESUMO

Somatosensory evoked potentials (SSEPs) are a very sensitive measure of the functional integrity of the neuroaxis, including peripheral and central structures. When used in diagnostic mode they can provide additional information regarding the probable areas of dysfunction. SSEPs were recorded from 44 children (64 feet with congenital talipes equinovarus, CTEV), between the ages of 2 to 15 years, who had structural CTEV deformity previously treated by surgery, with no clinical evidence of neurological deficit. SSEPs were elicited after sequential and bilateral stimulation (0.1 ms/5 Hz/10 to 20 mA) of the posterior tibial nerve and the common peroneal nerve and were recorded cortically (P40). In half the children, additional recordings were conducted at the knee (N5), the first lumbar spinous process (N14), and the seventh cervical spinous process (N20). Eighteen children had abnormal responses, four children had non-reproducible responses, and 22 children had normal responses. Analysis of the data at different levels of the nervous system showed that eight children had abnormality at the spinal level. The surgical outcome was influenced by the neurological abnormality, with an excellent or good outcome in 34 of 36 feet with normal neurology and 19 of 28 feet where a deficit was present (p<0.05). These findings support the neurological theory as an etiological factor in CTEV deformity.


Assuntos
Pé Torto Equinovaro/fisiopatologia , Potenciais Somatossensoriais Evocados , Doenças do Sistema Nervoso/diagnóstico , Adolescente , Sistema Nervoso Central/fisiologia , Criança , Pré-Escolar , Pé Torto Equinovaro/complicações , Pé Torto Equinovaro/etiologia , Estimulação Elétrica , Feminino , Humanos , Masculino , Doenças do Sistema Nervoso/complicações , Sistema Nervoso Periférico/fisiologia , Sensibilidade e Especificidade
19.
Cancer ; 89(4): 881-9, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10951353

RESUMO

BACKGROUND: Tobacco use is an important risk factor in cancer, cancer recurrence, and increased treatment morbidity, but limited information is available about interventions for tobacco cessation used in oncology clinical practice. In 1996, the Agency for Health Care Policy Research (AHCPR) published the first evidence-based smoking cessation guideline for use by health professionals. Using the AHCPR guideline as a framework, the authors describe the frequency of tobacco interventions provided by oncology nurses. METHODS: A questionnaire was mailed to 4000 randomly selected members of the Oncology Nursing Society in winter of 1998. Of those who were mailed questionnaires, 1508 respondents (38%) were available for analysis. RESULTS: The typical respondent was female, 44 years of age, and had practiced as an oncology nurse for 12 years. Seven percent were current smokers, and 30% were former smokers. Most (86%) encountered smokers on a weekly basis, but only 10% had heard of the AHCPR guideline. The majority (64%) assessed and documented tobacco status, 38% assessed readiness to quit. Few went on to provide interventions: 36% provided counseling, 32% provided cessation advice, 24% recommended nicotine replacement, and 16% taught skills to prevent relapse. Common barriers included perceived lack of patient motivation (74%) and the nurse's lack of time (52%) and skills (53%). The majority stated that they wanted to help patients stop smoking (88%) but needed additional training (92%). CONCLUSIONS: Documentation of tobacco status alone is not adequate in assisting patients with smoking cessation. Greater efforts are needed to educate oncology nurses about the range of tobacco interventions available and to facilitate their use in clinical settings.


Assuntos
Enfermagem Oncológica , Abandono do Hábito de Fumar/métodos , Fumar/efeitos adversos , Adulto , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Neoplasias/etiologia , Neoplasias/prevenção & controle , Enfermeiras e Enfermeiros , Enfermagem Oncológica/métodos , Enfermagem Oncológica/organização & administração , Serviço Hospitalar de Oncologia , Apoio Social , Inquéritos e Questionários , Recursos Humanos
20.
Biochem Genet ; 38(1-2): 13-25, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10862356

RESUMO

Twenty-one whitefly populations in the genus Bemisia were evaluated for genetic variation at 3 allozyme loci. Nine of the 22 populations that exhibited polymorphic loci were subjected to allozyme analysis using a minimum of 10 enzymes, representing 10 to 14 distinct loci. Among those nine variants examined, calculated genetic distances ranged between 0.03 and 0.52, with three main groups emerging from the analysis. One group comprised two closely related Western Hemisphere variants of B. tabaci: type A from California, United States and a geographically proximal population from Culiacan, Mexico. A second cluster contained five collections previously identified as B. tabaci type B and Bemisia argentifolii, while a third group contained a single population from Benin, Africa. The latter two groups were grouped separately from New World populations and are thought to have a recent origin in the Eastern Hemisphere.


Assuntos
Hemípteros/classificação , Hemípteros/genética , Animais , California , Esterases/genética , Frequência do Gene , Glucose-6-Fosfato Isomerase/genética , Focalização Isoelétrica , Isoenzimas/genética , México , Fosfoglucomutase/genética
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