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1.
Geohealth ; 6(11): e2022GH000706, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36348989

RESUMO

As marginalized communities continue to bear disproportionate impacts from environmental hazards, we urgently call for researchers and institutions to elevate the principles of Environmental Justice. The American Geophysical Union (AGU) GeoHealth section supports members' engagement in health-related community-engaged and community-led transdisciplinary research. We highlight intersectional research that provides examples and actions for both individuals and organizations on community science and trust building, removing barriers created by scientific agency priorities and career expectations, and opportunities in education and policy. Justice does not start or end at one meeting; this is ongoing work that is active, evolving, and an ethical responsibility of AGU's membership.

2.
Ned Tijdschr Geneeskd ; 1642021 02 04.
Artigo em Holandês | MEDLINE | ID: mdl-33651501

RESUMO

Pancreatic cystic neoplasms are increasingly detected in the general population. Although most of these lesions are benign, some are (pre)malignant and require follow-up or even surgical intervention. Three cases are presented and used to discuss the clinical implications of the renewed European Guideline on pancreatic cystic neoplasms in which relative and absolute indications for resection are proposed. In the first case, a pancreatic cystic lesion was found on abdominal ultrasound in a 77-year old female patient. After endoscopic ultrasound was performed, a serous cystic neoplasm was diagnosed without need for surveillance. In a 57-year old male, an abdominal MRI was performed to further assess an incidentally found pancreatic cystic lesion. Based on the MRI, a side-branch intraductal papillary mucinous neoplasm (SB-IPMN) was diagnosed and yearly surveillance was initiated. A 61-year old male underwent a laparoscopic distal pancreatectomy because of a mixed-type IPMN (MT-IPMN). The pathological results showed an IPMN with high-grade dysplasia.


Assuntos
Cistadenoma Mucinoso/diagnóstico , Cistadenoma Seroso/diagnóstico , Neoplasias Intraductais Pancreáticas/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Idoso , Cistadenoma Mucinoso/cirurgia , Cistadenoma Seroso/cirurgia , Endossonografia , Feminino , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Pancreatectomia/métodos , Neoplasias Intraductais Pancreáticas/cirurgia , Neoplasias Pancreáticas/cirurgia
3.
Nat Commun ; 11(1): 2749, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32488012

RESUMO

The tumour microenvironment (TME) forms a major obstacle in effective cancer treatment and for clinical success of immunotherapy. Conventional co-cultures have shed light onto multiple aspects of cancer immunobiology, but they are limited by the lack of physiological complexity. We develop a human organotypic skin melanoma culture (OMC) that allows real-time study of host-malignant cell interactions within a multicellular tissue architecture. By co-culturing decellularized dermis with keratinocytes, fibroblasts and immune cells in the presence of melanoma cells, we generate a reconstructed TME that closely resembles tumour growth as observed in human lesions and supports cell survival and function. We demonstrate that the OMC is suitable and outperforms conventional 2D co-cultures for the study of TME-imprinting mechanisms. Within the OMC, we observe the tumour-driven conversion of cDC2s into CD14+ DCs, characterized by an immunosuppressive phenotype. The OMC provides a valuable approach to study how a TME affects the immune system.


Assuntos
Plasticidade Celular/fisiologia , Células Dendríticas/metabolismo , Melanoma/metabolismo , Microambiente Tumoral/fisiologia , Comunicação Celular , Sobrevivência Celular , Técnicas de Cocultura , Fibroblastos/patologia , Humanos , Queratinócitos/patologia , Melanoma/imunologia , Melanoma/patologia , Pele/patologia , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Microambiente Tumoral/imunologia , Melanoma Maligno Cutâneo
4.
Geohealth ; 2(1): 6-24, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32158997

RESUMO

Valley fever is endemic to the southwestern United States. Humans contract this fungal disease by inhaling spores of Coccidioides spp. Changes in the environment can influence the abundance and dispersal of Coccidioides spp., causing fluctuations in valley fever incidence. We combined county-level case records from state health agencies to create a regional valley fever database for the southwestern United States, including Arizona, California, Nevada, New Mexico, and Utah. We used this data set to explore how environmental factors influenced the spatial pattern and temporal dynamics of valley fever incidence during 2000-2015. We compiled climate and environmental geospatial data sets from multiple sources to compare with valley fever incidence. These variables included air temperature, precipitation, soil moisture, surface dust concentration, normalized difference vegetation index, and cropland area. We found that valley fever incidence was greater in areas with warmer air temperatures and drier soils. The mean annual cycle of incidence varied throughout the southwestern United States and peaked following periods of low precipitation and soil moisture. From year-to-year, however, autumn incidence was higher following cooler, wetter, and productive springs in the San Joaquin Valley of California. In southcentral Arizona, incidence increased significantly through time. By 2015, incidence in this region was more than double the rate in the San Joaquin Valley. Our analysis provides a framework for interpreting the influence of climate change on valley fever incidence dynamics. Our results may allow the U.S. Centers for Disease Control and Prevention to improve their estimates of the spatial pattern and intensity of valley fever endemicity.

5.
Mol Psychiatry ; 21(11): 1573-1588, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27698428

RESUMO

Human neural progenitors derived from pluripotent stem cells develop into electrophysiologically active neurons at heterogeneous rates, which can confound disease-relevant discoveries in neurology and psychiatry. By combining patch clamping, morphological and transcriptome analysis on single-human neurons in vitro, we defined a continuum of poor to highly functional electrophysiological states of differentiated neurons. The strong correlations between action potentials, synaptic activity, dendritic complexity and gene expression highlight the importance of methods for isolating functionally comparable neurons for in vitro investigations of brain disorders. Although whole-cell electrophysiology is the gold standard for functional evaluation, it often lacks the scalability required for disease modeling studies. Here, we demonstrate a multimodal machine-learning strategy to identify new molecular features that predict the physiological states of single neurons, independently of the time spent in vitro. As further proof of concept, we selected one of the potential neurophysiological biomarkers identified in this study-GDAP1L1-to isolate highly functional live human neurons in vitro.


Assuntos
Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Potenciais de Ação/fisiologia , Diferenciação Celular/fisiologia , Células Cultivadas , Eletrofisiologia , Humanos , Células-Tronco Pluripotentes Induzidas/fisiologia , Aprendizado de Máquina , Neurônios/metabolismo , Técnicas de Patch-Clamp , Células-Tronco Pluripotentes , RNA
6.
Mol Psychiatry ; 21(1): 49-61, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26503761

RESUMO

The brain's serotonergic system centrally regulates several physiological processes and its dysfunction has been implicated in the pathophysiology of several neuropsychiatric disorders. While in the past our understanding of serotonergic neurotransmission has come mainly from mouse models, the development of pluripotent stem cell and induced fibroblast-to-neuron (iN) transdifferentiation technologies has revolutionized our ability to generate human neurons in vitro. Utilizing these techniques and a novel lentiviral reporter for serotonergic neurons, we identified and overexpressed key transcription factors to successfully generate human serotonergic neurons. We found that overexpressing the transcription factors NKX2.2, FEV, GATA2 and LMX1B in combination with ASCL1 and NGN2 directly and efficiently generated serotonergic neurons from human fibroblasts. Induced serotonergic neurons (iSNs) showed increased expression of specific serotonergic genes that are known to be expressed in raphe nuclei. iSNs displayed spontaneous action potentials, released serotonin in vitro and functionally responded to selective serotonin reuptake inhibitors (SSRIs). Here, we demonstrate the efficient generation of functional human serotonergic neurons from human fibroblasts as a novel tool for studying human serotonergic neurotransmission in health and disease.


Assuntos
Técnicas Citológicas/métodos , Fibroblastos/fisiologia , Neurônios Serotoninérgicos/fisiologia , Animais , Astrócitos/fisiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linhagem Celular , Transdiferenciação Celular/fisiologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Fator de Transcrição GATA2/genética , Fator de Transcrição GATA2/metabolismo , Vetores Genéticos , Proteína Homeobox Nkx-2.2 , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Células-Tronco Embrionárias Humanas/fisiologia , Humanos , Proteínas com Homeodomínio LIM/genética , Proteínas com Homeodomínio LIM/metabolismo , Lentivirus/genética , Camundongos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma , Proteínas de Peixe-Zebra
8.
Transgenic Res ; 19(6): 1001-15, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20204695

RESUMO

Citrus tristeza virus (CTV) causes one of the most destructive viral diseases of citrus worldwide. Generation of resistant citrus genotypes through genetic engineering could be a good alternative to control CTV. To study whether production of single-chain variable fragment (scFv) antibodies in citrus could interfere and immunomodulate CTV infection, transgenic Mexican lime plants expressing two different scFv constructs, separately and simultaneously, were generated. These constructs derived from the well-referenced monoclonal antibodies 3DF1 and 3CA5, specific against CTV p25 major coat protein, whose mixture is able to detect all CTV isolates characterized so far. ScFv accumulation levels were low and could be readily detected just in four transgenic lines. Twelve homogeneous and vigorous lines were propagated and CTV-challenged by graft inoculation with an aggressive CTV strain. A clear protective effect was observed in most transgenic lines, which showed resistance in up to 40-60% of propagations. Besides, both a delay in symptom appearance and attenuation of symptom intensity were observed in infected transgenic plants compared with control plants. This effect was more evident in lines carrying the 3DF1scFv transgene, being probably related to the biological functions of the epitope recognized by this antibody. This is the first report describing successful protection against a pathogen in woody transgenic plants by ectopic expression of scFv recombinant antibodies.


Assuntos
Citrus aurantiifolia/genética , Citrus aurantiifolia/virologia , Closterovirus/imunologia , Doenças das Plantas/prevenção & controle , Anticorpos de Cadeia Única/genética , Anticorpos Antivirais/genética , Sequência de Bases , Citrus aurantiifolia/imunologia , Closterovirus/patogenicidade , Primers do DNA/genética , Expressão Gênica , Engenharia Genética , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Doenças das Plantas/virologia , Planticorpos/genética , Plantas Geneticamente Modificadas
9.
Phytopathology ; 96(3): 320-5, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18944448

RESUMO

ABSTRACT The dynamics of virus interference between two isolates of Plum pox virus (PPV) belonging to the main PPV types, D and M, were analyzed in Japanese plum (Prunus salicina) by challenge inoculations. To assess the consequences of a PPV-M infection on plum already infected with PPV-D, and vice versa (predominance of one of the strains, recombination, synergism, symptoms aggravation, and so on), 30 Japanese plum trees were graft inoculated with PPV-D or PPV-M isolates in quarantine conditions. One year postinoculation, in the event that the inoculated isolates were detected in the whole plant, a second challenge inoculation (PPV-M or PPV-D, respectively) was performed by grafting. The presence of PPV-D, PPV-M, or both was monitored for 7 years by double-antibody sandwich indirect enzyme-linked immunosorbent assay using specific monoclonal antibodies. Reverse transcription-polymerase chain reaction (RT-PCR) with D- and M-specific primers confirmed the serological typing. Real-time RT-PCR assays were performed using D- and M-specific fluorescent 3' minor groove binder-DNA probes, which were able to detect and quantify PPV populations in the inoculated plants with greater precision. The presence of PPV-D in Japanese plum did not cross-protect the trees against PPV-M infection. In PPV-D-infected plants, the PPV-M strain used as challenge inoculum behaved differently depending on the plum cultivar assayed. In cv. Black Diamond, PPV-M invaded the plant progressively, displacing the previous PPV-D population; whereas, in cv. Sun Gold, both PPV isolates coexisted in the plant. In contrast, the PPV-D isolate used was unable to infect plants of both cultivars in which a PPV-M population already was established. After 7 years, no synergism was observed and no recombination event between PPV-D and PPV-M genomes was detected.

10.
Plant Dis ; 90(8): 1012-1018, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30781292

RESUMO

Transgenic clones C2, C3, C4, C5, C6, and PT-6, of plum (Prunus domestica L.) transformed with the coat protein (CP) gene of Plum pox virus (PPV), PT-23 transformed with marker genes only, and nontransgenic B70146 were evaluated for sharka resistance under high infection pressure in field trials in Poland and Spain. These sites differed in climatic conditions and virus isolates. Transgenic clone C5 showed high resistance to PPV at both sites. None of the C5 trees became naturally infected by aphids during seven (Spain) or eight (Poland) years of the test, although up to 100% of other plum trees (transgenic clones and nontransgenic control plants) grown in the same conditions showed disease symptoms and tested positively for PPV. Although highly resistant, C5 trees could be infected artificially by chip budding or via susceptible rootstock. Infected C5 trees showed only a few mild symptoms on single, isolated shoots, even up to 8 years post inoculation. These results clearly indicate the long-term nature and high level of resistance to PPV obtained through genetically engineered resistance.

11.
J Virol Methods ; 96(1): 33-41, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11516487

RESUMO

A single-step multiplex RT-PCR was developed for the simultaneous and colourimetric detection of six RNA viruses (Cucumber mosaic virus, Cherry leaf roll virus, strawberry latent ringspot virus, Arabis mosaic virus, Olive latent-1 virus and Olive latent-2 virus) which infect olive trees. Six compatible primer set for one-step RT-PCR amplification in a single closed-tube and 3' digoxigenin labelled probes were designed in optimal, specific and conserved regions. The method has been assessed with 195 Spanish field olive trees, suggesting that approximately 1.5% of the tested material was infected by Cucumber mosaic virus and 0.5% by Cherry leaf roll virus. This method saves time and reagent costs compared with monospecific RT-PCR which needs several reactions for the same number of tests. Using colourimetric detection, it is possible to analyse many samples, it increases sensitivity 10-fold, and whilst facilitating the interpretation of results, it avoids the use of gels and the toxic ethidium bromide. The method could be used routinely for sanitary and certification programmes.


Assuntos
Magnoliopsida/virologia , Vírus de RNA/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Árvores/virologia , Colorimetria/métodos , Primers do DNA , Doenças das Plantas/virologia , Vírus de Plantas/genética , Vírus de Plantas/isolamento & purificação , Vírus de RNA/genética , Sensibilidade e Especificidade
12.
Virus Res ; 71(1-2): 85-95, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11137164

RESUMO

The first outbreak of citrus tristeza disease in Spain caused by Citrus tristeza virus (CTV) was recorded in 1957 in the Valencian Community (VC). In total c. 40 million trees, mainly of sweet orange and mandarin grafted on sour orange rootstocks, declined due to CTV. Large-scale surveys in different municipalities of the VC indicated that the disease spread very fast. Incidence increased from 11% in 1989 to 53% in 1998. Toxoptera aurantii and Aphis spiraecola (inefficient aphid vectors of CTV) predominated before 1985-87. Since then the relatively efficient vector Aphis gossypii has become dominant and induced an epidemic that has been modelled. The large number of A.gossypii that visited each clementine tree (estimated to exceed 97000 per year) explained the difference between the temporal pattern of spread of CTV in clementine which followed the Gompertz model and that in sweet orange (logistic model). The susceptibility of the different citrus species to CTV infection by aphids seems to depend on the number of young, succulent shoots produced. The epidemiological data allowed specific recommendations to be made to growers in order to facilitate a change to a modern citrus industry based on the use of selected varieties grafted on tristeza-tolerant rootstocks produced within a certification scheme. This has been done already in almost 90% of the VC citrus-growing area. The tristeza problem has been solved unless more aggressive isolates are introduced and become prevalent.


Assuntos
Citrus/virologia , Closterovirus , Doenças das Plantas/virologia , Árvores/virologia , Animais , Afídeos/virologia , Closterovirus/isolamento & purificação , Insetos Vetores/virologia , Espanha
13.
Nucleic Acids Res ; 27(6): 1564-5, 1999 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10037824

RESUMO

A device and improved method based on the use of a compartmentalized Eppendorf tube that allows capture, reverse transcription and nested-PCR in a single closed-tube has been developed and patented. The main advantages of the system are the high sensitivity obtained, the simplicity, the low risk of contamination and the easy establishment of adequate conditions for nested-PCR. The method has been successfully applied to the detection and characterization of citrus tristeza closterovirus and plum pox potyvirus isolates in plant tissues and single aphids squashed on paper. This device and methodology could be easily adapted to the detection of other targets.


Assuntos
Afídeos/virologia , Closterovirus/isolamento & purificação , Vírus Eruptivo da Ameixa/isolamento & purificação , Reação em Cadeia da Polimerase/instrumentação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/instrumentação , Animais
14.
Phytopathology ; 88(3): 198-204, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18944965

RESUMO

ABSTRACT Plum pox potyvirus (PPV) isolates may be divided into four groups separated by serological, molecular, and epidemiological differences. Monoclonal antibodies specific for the two major groups of isolates, represented by the D and M serotypes of the virus, have been obtained. Polymerase chain reaction (PCR)-based assays allowing the direct detection and differentiation of PPV isolates have also been developed. We now report on a large-scale comparison of these two typing approaches. The results obtained show an overall excellent correlation between the results obtained in indirect double-antibody sandwich enzyme-linked immunosorbent assay using PPV-D- and PPV-M-specific monoclonal antibodies and those derived from either specific PCR assays or restriction fragment length polymorphism analysis of PCR fragments. Without exception, all isolates reacting positively with the PPV-M-specific monoclonal antibody were found to belong to the M serotype using the PCR-based assays, while 51 out of 53 isolates recognized by the D-specific monoclonal antibodies belonged to the D serotype according to the PCR typing results. However, failure to react with a specific monoclonal antibody did not prove as effective a predictor of the serotype of the isolate analyzed. In a few cases, the results obtained with the various techniques diverged, indicating low level variability of the epitopes recognized by the serotype-specific monoclonal antibodies. Isolates belonging to the two minor groups of PPV (El Amar and Cherry) also gave divergent results, indicating that the current typing assays are not suited for the analysis of such isolates.

15.
J Virol Methods ; 68(2): 127-37, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9389402

RESUMO

Two techniques for simultaneous detection and typing of plum pox potyvirus (PPV) isolates belonging to the D or M serotypes, heminested PCR (H-PCR) and PCR-ELISA, have been developed. Ten PPV isolates typed using PPV-D and PPV-M specific monoclonal antibodies by ELISA-DASI were used to validate these two methods. The results obtained show a complete coincidence of the nucleic acid-based techniques with the serological data. When serial dilutions of infected plant extracts were assayed, H-PCR and PCR-ELISA were found to be 100 times more sensitive than the more conventional immunocapture-PCR (IC-PCR) assay. Testing of 228 PPV-infected fruit tree samples coming from different hosts and locations indicated that so far only PPV type D appears to be present in Spain and in Chile. Coupled with print-capture sample preparation (Olmos et al., Nucl. Acids Res. 24, 2192-2193, 1996) the increased sensitivity provided by heminested-PCR allowed the detection of PPV targets of D and M types, in wingless individuals of the aphid vector Aphis gossypii.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Vírus Eruptivo da Ameixa/classificação , Vírus Eruptivo da Ameixa/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Sequência de Aminoácidos , Animais , Afídeos/virologia , Sequência de Bases , Sondas de DNA , Frutas/virologia , Dados de Sequência Molecular , Plantas Tóxicas , Vírus Eruptivo da Ameixa/genética , Sensibilidade e Especificidade , Sorotipagem/métodos , Nicotiana/virologia
16.
J Appl Bacteriol ; 78(4): 437-44, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7538107

RESUMO

The characteristics of two monoclonal antibodies (Mabs), A23/1221.59.44.d.3 (1221) and A23/1239.36.64.e.2 (1239), against Erwinia carotovora subsp. atroseptica serogroup I produced in this study were compared with those of two other independently obtained Mabs, 4G4 in Spain and 4F6 in Canada, using different strains as immunogen and different screening procedures. The reaction pattern of Mabs 1221 and 1239 determined by indirect ELISA on over 200 bacterial strains including five E.c. atroseptica and 36 E.c. carotovora serogroups, seven Erw. chrysanthemi biovars, 23 other plant bacterial pathogens and 33 saprophytic bacteria from potato was similar to that of 4G4. Specificity for E.c. atroseptica serogroup I was improved, especially when skimmed milk (Marvel) was used instead of bovine serum albumin as blocking agent. Mabs 1221, 1239 and 4G4 reacted positively with all 22 E.c. atroseptica serogroup I, the dominant E.c. atroseptica serogroup on potato, strains tested and only with two out of five E.c. atroseptica serogroup XXII strains, one E.c. carotovora serogroup XXI strain and one strain of a saprophytic bacterium, Comamonas sp. Essentially similar results were obtained when examined by immunofluorescence. Characterization of the four Mabs showed that they were IgG3 and SDS-PAGE/immunoblot results suggested that they were probably against the O-side chain of bacterial cell wall lipopolysaccharides. In competition ELISA between biotin-labelled and unlabelled Mabs, the competition pattern of the four Mabs was similar.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Anticorpos Antibacterianos/imunologia , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos/imunologia , Epitopos/imunologia , Pectobacterium carotovorum/imunologia , Animais , Anticorpos Antibacterianos/biossíntese , Anticorpos Monoclonais/biossíntese , Ensaio de Imunoadsorção Enzimática , Feminino , Imunofluorescência , Lipopolissacarídeos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pectobacterium carotovorum/classificação , Coelhos , Sorotipagem
17.
Appl Environ Microbiol ; 60(6): 2076-85, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16349293

RESUMO

Seven monoclonal antibodies (MAbs) to Erwinia carotovora subsp. atroseptica have been produced. One, called 4G4, reacted with high specificity for serogroup I of E. carotovora subsp. atroseptica, the most common serogroup on potato tubers in different serological assays. Eighty-six strains belonging to different E. carotovora subsp. atroseptica serogroups were assayed. Some strains of serogroup XXII also reacted positively. No cross-reactions were observed against other species of plant pathogenic bacteria or 162 saprophytic bacteria from potato tubers. Only one strain of E. chrysanthemi from potato cross-reacted. A comparison of several serological techniques to detect E. carotovora subsp. atroseptica on potato tubers was performed with MAb 4G4 or polyclonal antibodies. The organism was extracted directly from potato peels of artificially inoculated tubers by soaking or selective enrichment under anaerobiosis in a medium with polypectate. MAb 4G4 was able to detect specifically 240 E. carotovora subsp. atroseptica cells per ml by indirect immunofluorescence and immunofluorescence colony staining and after soaking by ELISA-DAS (double-antibody sandwich enzyme-linked immunosorbent assay) after enrichment. The same amount of cells was detected by using immunolectrotransfer with polyclonal antibodies, and E. carotovora subsp. atroseptica and subsp. carotovora were distinguished by the latter technique. ELISA-DAS using MAb 4G4 with an enrichment step also efficiently detected E. carotovora subsp. atroseptica in naturally infected tubers and plants.

18.
Arch Virol ; 135(3-4): 293-304, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7526822

RESUMO

Monoclonal antibodies (MAbs) specific to plum pox virus (PPV) were prepared by fusing myeloma cell lines to spleen cells of mice immunized with purified virus, including virus prepared with protease inhibitors to preserve the integrity of the coat protein (CP). The characterized MAbs could be used in ELISA to differentiate several Mediterranean PPV isolates differing in their geographical origin and CP size. At least seven antigenic sites could be established based on the recognition pattern and competition binding analysis, and the epitopes could be classified in three groups by Western blot analysis of intact and trypsin digested virus particles. By means of electron microscopy the epitopes could be seen to be located on the surface of the virus particles.


Assuntos
Anticorpos Monoclonais , Antígenos Virais/análise , Epitopos/análise , Vírus Eruptivo da Ameixa/classificação , Animais , Western Blotting/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Geografia , Hibridomas , Camundongos/imunologia , Microscopia Imunoeletrônica/métodos , Mieloma Múltiplo , Plantas/virologia , Vírus Eruptivo da Ameixa/isolamento & purificação , Vírus Eruptivo da Ameixa/ultraestrutura , Espanha , Baço/imunologia
19.
Appl Environ Microbiol ; 59(6): 1805-12, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16348957

RESUMO

The variation in biochemical and serological features of 128 isolates of Pseudomonas corrugata has been studied with 56 isolates from Spain and 72 isolates from other countries. Isolates were analyzed with common diagnostic tests and with the AP150CHE system. Variability among isolates for some standard tests usually listed as positive or negative for this species, such as arginine dihydrolase and gelatin hydrolysis, lipase and lecithinase activities, pigment production, and wrinkled colony morphology, was observed. Three antisera were raised against the type strain and two Spanish isolates from tomato and pepper plants. Serological reactions were studied by indirect immunofluorescence and indirect enzyme-linked immunosorbent assay. Eighty-three isolates reacted with a single antiserum, 6 reacted with two antisera, and none reacted with three antisera. Thirty-nine isolates did not react with any of the three antisera. These results suggest that serology will not be a useful method for routine diagnosis of P. corrugata unless common antigens can be identified. Electrophoresis and immunoelectrotransfer were used to study the antigens involved. Each antiserum reacted with whole-cell lysates, giving two common bands for P. corrugata isolates and other Pseudomonas species and a ladder-like pattern characteristic of lipopolysaccharides (LPS). Common bands were not observed after proteinase K treatment. More than 10 LPS patterns were distinguished in 98 isolates after silver staining of polyacrylamide gels. There was no correlation between the geographical origin or host of the isolates and the LPS patterns. A correlation between LPS groups and serological reaction was observed.

20.
Appl Environ Microbiol ; 55(3): 741-6, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16347881

RESUMO

The effectiveness of Agrobacterium radiobacter K84, 0341, and a K84 non-agrocin-producing mutant (K84 Agr) in biological control of crown gall on rootstocks of stone fruit trees was determined in three experiments. In experiment 1, K84 and 0341 controlled crown gall on plum plants in soil inoculated with two strains of Agrobacterium tumefaciens resistant to agrocin 84. In experiment 2, K84 controlled crown gall on peach plants in soils inoculated with strains of A. tumefaciens sensitive or resistant to agrocin 84 or with a mixture of both. However, the effectiveness of K84 was higher against the sensitive strain than against the resistant strain. There was a residual effect of K84 from one year to another in soil inoculated with the sensitive strains. In experiment 3, K84 and K84 Agr controlled crown gall on plum and peach plants in soils inoculated with strains of A. tumefaciens sensitive or resistant to agrocin 84. The control afforded by K84 was higher than that provided by K84 Agr against the sensitive strain but was similar against the resistant strain.

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