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1.
Plant Dis ; 98(1): 154, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30708588

RESUMEN

In April and May of 2012, bell pepper (Capsicum annuum) plants exhibiting symptoms that resembled those of the bacterium 'Candidatus Liberibacter solanacearum' infection (2,4) were observed in commercial pepper fields in several departments in Honduras, including Francisco Morazán, Ocotepeque, El Paraíso, and Olancho. Many of the fields were infested with the psyllid Bactericera cockerelli, a vector of 'Ca. L. solanacearum' (3). The plants exhibited chlorotic or pale green apical growth and leaf cupping, sharp tapering of the leaf apex, shortened internodes, and overall stunting (2,4). All cultivars grown were affected and 20 to 75% of plants in each field were symptomatic. Pepper (var. Nataly) plant samples were collected from a total of eight affected fields (two fields per department). Total DNA was extracted from the top whole leaf tissue of a total of 19 plants, including 14 symptomatic and 5 asymptomatic pepper plants, with the cetyltrimethylammonium bromide (CTAB) buffer extraction method (1). The DNA samples were then tested by PCR using specific primer sets OA2/OI2c and OMB 1482f/2086r to amplify a portion of 16S rDNA and the outer membrane protein (OMB) genes, respectively, of 'Ca. L. solanacearum' (1,2). OMB gene and 16S rDNA fragments of 605 and 1,168 bp, respectively, were amplified from the DNA of 7 of 14 (50%) symptomatic plants with each primer set, indicating the presence of 'Ca. L. solanacearum.' No 'Ca. L. solanacearum' was detected in the five asymptomatic plants with either primer sets. DNA amplicons with both primer sets were cloned from the DNA of plant samples collected from each of the three departments: Francisco Morazán (in the locality of Zamorano), Ocotepeque (municipality of Plan del Rancho in Sinuapa), and El Paraíso (municipality of Danlí), and four clones of each of the six amplicons were sequenced. BLASTn analysis of the 16S rDNA resulted in a single consensus sequence for all three locations (deposited in GenBank as Accession Nos. KF188226, KF188227, and KF188228) and showed 100% identity to numerous 16S rDNA sequences of 'Ca. L. solanacearum' in GenBank, including accessions HM245242, JF811596, and KC768319. Similarly, identical OMB consensus sequences were observed in all three locations (deposited in GenBank as KF188230, KF188231, and KF188233) that are 100% identical to several 'Ca. L. solanacearum' sequences in GenBank (e.g., KC768331 and CP002371) along with a second consensus sequence (deposited in GenBank as accession KF188232) from Ocotepeque that was 99% identical to the consensus sequence from the three locations and sequences in GenBank. To our knowledge, this is the first report of 'Ca. L. solanacearum' associated with pepper crops in Honduras, where pepper constitutes an economically important commodity. This bacterium has also caused millions of dollars in losses to potato and several other solanaceous crops in United States, Mexico, Central America, and New Zealand (1,2,3,4). Furthermore, 'Ca. L. solanacearum' has been reported to severely damage carrot crops in Europe, where it is transmitted to carrot by the psyllids Trioza apicalis and Bactericera trigonica (3). Monitoring this pathogen and its vectors will prevent serious damage they cause to economically important crops. References: (1) J. M. Crosslin. Southwest. Entomol. 36:125, 2011. (2) L. W. Liefting et al. Plant Dis. 93:208, 2009. (3) J. E. Munyaneza. Am. J. Pot. Res. 89:329, 2012. (4) J. E. Munyaneza et al. Plant Dis. 93:1076, 2009.

2.
Plant Dis ; 97(12): 1654, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30716844

RESUMEN

In May of 2012, eggplant (Solanum melongena) plants in an experimental research plot located at Zamorano in the Department of Francisco Morazán, Honduras, were observed with symptoms that included leaf chlorosis and cupping, overall stunting, and production of small and malformed fruits. The research plot was planted next to a commercial tomato field heavily infested with the psyllid Bactericera cockerelli, a vector of 'Candidatus Liberibacter solanacearum' (1,2,3). This bacterium severely affects potato and other solanaceous species and is the putative causal agent of zebra chip disease (2,3). The plot was planted with the eggplant variety 'China' and about 25% of the plants were symptomatic. A total of 10 eggplant samples, including five symptomatic and five asymptomatic plants, were collected from the plot. Total DNA was extracted from the leaf tissue of each of the collected plants with the cetyltrimethylammonium bromide (CTAB) buffer extraction method (1). The DNA samples were then tested by PCR using specific primer sets OA2/OI2c and OMB 1482f/2086r to amplify a portion of 16S rDNA and the outer membrane protein (OMB) genes, respectively, of 'Ca. L. solanacearum' (1,2). OMB gene and 16S rDNA fragments of 605 and 1,168 bp, respectively, were amplified from the DNA of two of the five (40%) symptomatic plants with each primer set, indicating the presence of 'Ca. L. solanacearum.' No 'Ca. L. solanacearum' was detected in the five asymptomatic plants with either primer sets. DNA amplicons with both primer sets were cloned from the DNA of the two 'Ca. L. solanacearum'-positive plant samples and four clones of each of the four amplicons were sequenced. BLASTn analysis of the 16S rDNA resulted in two independent but related consensus sequences (deposited in GenBank as Accession Nos. KF188224 and KF188225) and were 99% similar to each other. The two sequences showed 99 to 100% identity to a number of 16S rDNA sequences of 'Ca. L. solanacearum' in Genbank, including accessions HM245242, FJ811596, and KC768319. For the OMB amplicons, a single consensus sequence was obtained following clone sequencing and was deposited in GenBank as accession KF188229. BLASTn analysis of the sequence indicated that it was 100% identical to several OMB sequences of 'Ca. L. solanacearum' in GenBank, including accessions KC768331 and CP002371. To our knowledge, this is the first report of 'Ca. L. solanacearum' associated with eggplant in Honduras. Eggplant is an economically important commodity in Central America and serious damage to this crop due to this plant pathogen could expand throughout the region, especially if its insect vector B. cockerelli is not properly managed. 'Ca. L. solanacearum' has also caused millions of dollars in losses to potato and several other solanaceous crops in the United States, Mexico, Central America, and New Zealand (2,3). In addition, this bacterium severely damages carrot crops in Europe, where it is transmitted to carrot by the psyllids Trioza apicalis and B. trigonica (3,4). It is imperative that both 'Ca. L. solanacearum' and its insect vectors be effectively monitored and managed to minimize their threat to economically important vegetable crops in many parts of the world. References: (1) J. M. Crosslin et al. Southwest. Entomol. 36:125, 2011. (2) L. W. Liefting et al. Plant Dis. 93:208, 2009. (3) J. E. Munyaneza. Am. J. Pot. Res. 89:329, 2012. (4) J. E. Munyaneza et al. J. Econ. Entomol. 103:1060, 2010.

3.
Plant Dis ; 97(10): 1376, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30722168

RESUMEN

In April of 2012, tobacco (Nicotiana tabacum L.) plants with symptoms resembling those associated with viral infection were observed in commercial fields in the Department of El-Paraíso, Honduras. Symptoms on affected plants included apical leaf curling and stunting, overall chlorosis and plant stunting, young plant deformation with cabbage-like leaves, wilting, and internal vascular necrosis of stems and leaf petioles. All cultivars grown were affected, with disease incidence ranging from 5 to 80% of symptomatic plants per field. The fields were also heavily infested with the psyllid Bactericera cockerelli. This psyllid is a serious pest of solanaceous crops in the United States, Mexico, Central America, and New Zealand and has been shown to transmit the bacterium "Candidatus Liberibacter solanacearum" to potato, tomato, and other solanaceous species (2,3). Tobacco (cv. Habano criollo) plant samples were collected from one field in the municipality of Trojes. Initial testing of the plant samples for viruses, including Tobacco mosaic virus, Impatiens necrotic spot virus, Cucumber mosaic virus, and Potato virus Y, using Immunostrips (Agdia, Elkhart, IN) were negative. Total DNA was then extracted from leaf tissues of a total of 13 plants, including eight symptomatic plants and five asymptomatic plants with the cetyltrimethylammonium bromide (CTAB) buffer extraction method (2,4). The DNA samples were tested by PCR using specific PCR primer pairs OA2/OI2c and OMB 1482f/2086r, to amplify a portion of 16S rDNA and the outer membrane protein (OMB) gene of "Ca. L. solanacearum," respectively (2). All eight (100%) symptomatic plant samples were positive for "Ca. L. solanacearum" with both sets of primer pairs. "Ca. L. solanacearum" was not detected in the asymptomatic plants. The 16S rDNA and OMB gene amplicons of two plant samples each were cloned and four clones of each of the four amplicons were sequenced. BLASTn analysis of the consensus sequences confirmed "Ca. L. solanaeacrum" in the tobacco samples. The 16S rDNA consensus sequences (1,168 bp) of all amplicons were identical and showed 100% identity with several 16S rDNA sequences of "Ca. L. solanacearum" in GenBank (e.g., Accession Nos. HM245242, JF811596, and JX559779). The consensus sequence of the OMB amplicon (605 bp) showed 97 to 100% homology with a number of "Ca. L. solanacearum" OMB sequences in GenBank, including Accession Nos. CP002371, FJ914617, JN848754 and JN848752. The tobacco-associated consensus 16S rDNA and OMB sequences from this study were deposited in GenBank as Accession Nos. KC768320 and KC768328, respectively. To our knowledge, this is the first report of "Ca. L. solanacearum" associated with tobacco in Honduras, where this cash crop is economically important. This bacterium has also caused millions of dollars in losses to potato, tomato, and several other solanaceous crops in North and Central America and New Zealand, particularly in regions where B. cockerelli is present (3). Furthermore, "Ca. L. solanacearum" has caused significant economic damage to carrot crops in Europe, where it is transmitted by the psyllids Trioza apicalis in northern Europe (4) and B. trigonica in the Mediterranean region (1). References: (1) A. Alfaro-Fernandez et al. Plant Dis. 96:581, 2012. (2) J. M. Crosslin. Southwest. Entomol. 36:125, 2011. (3) J. E. Munyaneza. Am. J. Pot. Res. 89:329, 2012. (4) J. E. Munyaneza et al. J. Econ. Entomol. 103:1060, 2010.

4.
Plant Dis ; 97(10): 1375, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30722169

RESUMEN

Tomato (Lycopersicum esculentum) crops grown in several departments of Honduras and heavily infested with the psyllid Bactericera cockerelli were observed in April of 2012 with plant symptoms suggestive of "Candidatus Liberibacter solanacearum" infection. B. cockerelli is a serious pest of potato, tomato, and other solanaceous plants and a vector of "Ca. L. solanacearum" (1,2,3,4). The symptoms included overall chlorosis, severe stunting, leaf cupping, excessive branching of axillary shoots, and leaf purpling and scorching (2,3). Disease incidence ranged from 5 to 50% symptomatic plants per field. Tomato (cv. Pony) plant samples were collected from two psyllid-infested commercial fields in the municipalities of Danli and Comayagua in the departments of El-Paraiso and Comayagua, respectively. Total DNA was extracted from leaf tissues of 50 and 20 symptomatic and asymptomatic plants, respectively, with the cetyltrimethylammonium bromide (CTAB) buffer extraction method (1,3). The DNA samples were tested for "Ca. L. solanacearum" by PCR with primer pairs specific for 16S rDNA (OA2 and OI2c) and the outer membrane protein gene (OMB 1482f and 2086r) of the bacterium (1,2). Ten (20%) of the 50 symptomatic tomato samples were positive for "Ca. L. solanacearum" using both primer pairs and the remaining samples were negative for the bacterium with both primer sets. None of the 20 asymptomatic plants tested positive for "Ca. L. solanacearum". Amplicons from DNA of two plant samples (one plant/municipality) with each primer pair were cloned and four clones of each of the four amplicons were sequenced. BLASTn analysis of the 16S rDNA consensus sequences from the clones (deposited in GenBank as Accession Nos. KC768321 and KC768322) were identical for both locations and showed 99 to 100% identity to several "Ca. L. solanacearum" sequences in GenBank (e.g., JN848753, JN84856, and HM246509). The OMB consensus sequences from the two tomato plants (deposited in GenBank as KC768329 and KC768330) were 100% identical to OMB sequences of Lso in GenBank (CP002371 and JN48754, respectively). To our knowledge, this is the first report of "Ca. Liberibacter solanacearum" associated with tomato crops in Honduras. This bacterium has caused millions of dollars in losses to the tomato industry in the United States, Mexico, and New Zealand (2,3,4). Serious damages to tomato crops due to "Ca. L. solanacearum" could expand throughout Central America, especially in those countries where B. cockerelli occurs. References: (1) J. M. Crosslin. Southwest. Entomol. 36:125, 2011. (2) L. W. Liefting et al. Plant Dis. 93:208, 2009. (3) J. E. Munyaneza et al. Plant Dis. 93:1076, 2009. (4) J. E. Munyaneza. Am. J. Pot. Res. 89:329, 2012.

5.
Plant Dis ; 97(9): 1244, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30722439

RESUMEN

In April of 2012, tobacco (Nicotiana tabacum) plants with symptoms resembling those caused by viral infection were observed in commercial fields in several departments in Nicaragua, including Esteli and Nueva Segovia. Heavy infestations of the psyllid Bactericera cockerelli, a major insect pest of potato and other solanaceous crops and vector of the bacterium "Candidatus Liberibacter solanacearum" (Lso) (2,3), were observed in the affected fields. All cultivars grown were affected and 5 to 100% of plants in each field were symptomatic. Symptoms on affected plants included apical leaf curling and stunting, overall chlorosis and plant stunting, young plant deformation with cabbage-like leaves, wilting, internal vascular necrosis of stems and leaf petioles, and overall poor leaf quality. Plant samples were collected from a total of three psyllid-infested fields in the municipalities of Esteli, Condega, and Jalapa (one field/municipality). The plant samples were first tested for viruses, including Potato virus Y, Tobacco mosaic virus, Cucumber mosaic virus, and Impatiens necrotic spot virus, using Immunostrips (Agdia, Elkhart, IN) and no virus was detected. Total DNA was extracted from leaf tissues of a total of 22 plants, including 17 symptomatic plants and five asymptomatic plants from two cultivars (Corojo and Habano) with the cetyltrimethylammonium bromide (CTAB) buffer extraction method (2,4). The DNA samples were tested by PCR using specific primer pairs OA2/OI2c and OMB 1482f/2086r, to amplify a portion of 16S rDNA and the outer membrane protein (OMB) genes, respectively, of Lso (2). 16 rDNA and OMB gene-derived fragments of 1,168 and 605 bp, respectively, were amplified from the DNA of 13 of 17 (76.5%) symptomatic plants, indicating the presence of Lso. No Lso was detected in the five asymptomatic plants. DNA amplicons of three plant samples (one plant/field) with each primer pair were cloned and two to four clones of each of the six amplicons were sequenced. BLASTn analysis of the 16S rDNA consensus sequences was the same for all three locations (GenBank Accession Nos. KC768323, KC768324, and KC768325) and showed 100% identity to numerous 16 rDNA sequences of Lso in GenBank, including accessions HM245242, JF811596, and JX559779. Similarly, identical OMB consensus sequences were observed in all three locations (KC768331 and KC768332 for Jalapa and Condega, respectively) that are 97 to 100% identical to a number of Lso sequences in GenBank (e.g., CP002371, FJ914617, JN848754, and JN848752). A second OMB sequence was isolated from the Esteli sample (KC768333) that was 98% identical with the consensus sequences from this and other sites and 100% identical to an OMB sequence from Lso in GenBank (JN848754). To our knowledge, this is the first report of Lso associated with tobacco. Tobacco is an important crop in many parts of the world, including Central and South America. This bacterium has also caused millions of dollars in losses to potato and several other solanaceous crops in the Americas and New Zealand (3). In addition, this plant pathogen has been reported as serious pest of carrot in Europe, where it is associated with the psyllids Trioza apicalis and B. trigonica (1,4). References: (1) A. Alfaro-Fernandez et al. Plant Dis. 96:581, 2012. (2) J. M. Crosslin. Southwest. Entomol. 36:125, 2011. (3) J. E. Munyaneza. Am. J. Pot. Res. 89:329, 2012. (4) J. E. Munyaneza et al. J. Econ. Entomol. 103:1060, 2010.

6.
Plant Dis ; 97(9): 1245, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30722460

RESUMEN

In April of 2012, tomato plants (Solanum lycopersicum) grown near the town of Yuroconte in the municipality of La Palma, Chalatenango, El Salvador, were observed with symptoms resembling those of "Candidatus Liberibacter solanacearum" infection. The symptoms included overall chlorosis, severe stunting, leaf cupping, excessive branching of axillary shoots, and leaf purpling and scorching (1,2,3). Disease incidence in several fields in the area ranged from 40 to 60%. Heavy infestations of the potato/tomato psyllid, Bactericera cockerelli, were observed in the affected fields and this insect has been shown to transmit "Ca. L. solanacearum" to tomato and other solanaceous species (1,2,3). Leaf samples and psyllids were collected from one of the fields and total DNA was purified from the leaves of 8 and 10 symptomatic and asymptomatic plants, respectively (2,3). DNA was also extracted from the psyllids and the samples were tested by PCR for species confirmation. PCR oligonucleotide primers specific for both 16S rDNA (OA2 and OI2c) and a gene for a surface antigen for the outer membrane protein (OMB) (OMB 1482f and 2086r) of "Ca. L. solanacearum" were used to confirm the presence of the bacterium in infected tomatoes (1). Four of the eight symptomatic tomatoes (50%) tested positive for "Ca. L. solanacearum" using both primer pairs and all asymptomatic plants were negative for the bacterium. The collected psyllids were first identified through a morphological key, then verified using species-specific PCR primers (CO1 F3 and CO1 meltR) that generated a 94-bp fragment that was consistent with DNA from B. cockerelli (4). Amplicons generated with DNA from two plant samples with each primer pair were cloned and four clones of each of the four amplicons were sequenced. BLASTn analysis of the 16S rDNA consensus sequences from the clones (1,168 bp; deposited in GenBank as Accession Nos. KC768318 and KC768319) showed 100% identity to "Ca. L. solanacearum" sequences in GenBank (HM246509 and HM245242, respectively). Two OMB consensus sequences were 98% identical (deposited in GenBank as KC768326 and KC768327) and both sequences were 97 to 100% identical to a number of "Ca. L. solanacearum" sequences in GenBank (e.g., CP002371, FJ914617, JN848754, and JN848752). To our knowledge, this is the first report of "Ca. L. solanacearum" associated with tomato in El Salvador and the first formal report of the bacterium in the country. This bacterium has caused millions of dollars in losses to the tomato industry in New Zealand, Mexico and the United States (2,3). Tomatoes are an economically important commodity in Central America and are severely damaged by "Ca. L. solanacearum" infection. The confirmation of "Ca. L. solanacearum" infections in El Salvador alerts the agricultural sector to the presence of this serious pathogen. References: (1) J. M. Crosslin. Southwest. Entomol. 36:125, 2011. (2) L. W. Liefting et al. Plant Dis. 93:208, 2009. (3) J. E. Munyaneza et al. Plant Dis. 93:1076, 2009. (4) K. D. Swisher et al. Environ. Entomol. 41:1019, 2012.

7.
J Med Virol ; 83(5): 906-9, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21412799

RESUMEN

Multiple surfaces contaminated with rhinovirus were detected in hotel rooms by reverse transcriptase-polymerase chain reaction (RT-PCR) following occupancy by a cold sufferer. Whether infectious rhinovirus contaminates surfaces in homes and is transferred from surfaces to fingertips through normal activities is not known. Nasal secretions from 30 subjects with new colds were tested for rhinovirus genome by RT-PCR; infectious rhinovirus was sought with tissue cultures. Each subject identified 10 sites in their home touched during the preceding 24 hr. Samples from sites were tested for rhinovirus by RT-PCR and cell culture. Later, each subject's mucus (stored at -70°C) was deposited on surfaces for testing transfer to fingertips through daily life activities such as flipping a light switch, touching the telephone keypad, and holding the telephone handset. Nasal secretions from 16/30 subjects were positive for rhinovirus by RT-PCR; 66 (41%) of 160 surfaces in homes were positive. Contaminated surfaces included doorknobs (6 positive/18 tested), refrigerator door handles (8/14), TV remote controls (5/10), and bathroom faucets (8/10). Five (19%) of 26 RT-PCR positive sites from culture positive subjects were positive in cell culture. Nasal mucus from six culture positive subjects was deposited on objects. Infectious rhinovirus was detected on 22% of fingertips following contact with objects contaminated for 1 hr; transfer dropped to 3% after 24 hr of contamination, and 0% after 48 hr. Infectious rhinovirus found on surfaces in homes of people with colds can be transferred to fingertips, but infectivity of virus in mucus declines by 24 hr after deposition.


Asunto(s)
Resfriado Común/virología , Microbiología Ambiental , Dedos/virología , Rhinovirus/aislamiento & purificación , Adulto , Resfriado Común/transmisión , Humanos , Viabilidad Microbiana , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Factores de Tiempo , Virología/métodos , Cultivo de Virus/métodos
8.
Oncogene ; 27(10): 1489-500, 2008 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-17873912

RESUMEN

Aberrant regulation of signalling mechanisms that normally orchestrate embryonic development, such as the Hedgehog, Wnt and Notch pathways, is a common feature of tumorigenesis. In order to better understand the neoplastic events mediated by Hedgehog signalling, we identified over 200 genes regulated by Sonic Hedgehog in multipotent mesodermal cells. Widespread crosstalk with other developmental signalling pathways is evident, suggesting a complex network of interactions that challenges the often over-simplistic representation of these pathways as simple linear entities. Hes1, a principal effector of the Notch pathway, was found to be a target of Sonic Hedgehog in both C3H/10T1/2 mesodermal and MNS70 neural cells. Desert Hedgehog also elicited a strong Hes1 response. While Smoothened function was found necessary for upregulation of Hes1 in response to Sonic Hedgehog, the mechanism does not require gamma-secretase-mediated cleavage of Notch receptors, and appears to involve transcription factors other than RBP-Jkappa. Thus, we have defined a novel mechanism for Hes1 regulation in stem-like cells that is independent of canonical Notch signalling.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Proteínas Hedgehog/fisiología , Proteínas de Homeodominio/metabolismo , Receptores Notch/fisiología , Transducción de Señal/fisiología , Animales , Línea Celular , Proliferación Celular , Mesodermo/citología , Mesodermo/metabolismo , Mesodermo/fisiología , Ratones , Ratones Endogámicos C3H , Neuronas/metabolismo , Neuronas/fisiología , Factor de Transcripción HES-1
9.
Genome ; 45(2): 367-80, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11962634

RESUMEN

Extended flanking DNA sequences were characterized for five members of the wheat high molecular weight (HMW) glutenin gene family to understand more of the structure, control, and evolution of these genes. Analysis revealed more sequence conservation among orthologous regions than between paralogous regions, with differences mainly owing to transposition events involving putative retrotransposons and several miniature inverted transposable elements (MITEs). Both gyspy-like long terminal repeat (LTR) and non-LTR retrotransposon sequences are represented in the flanking DNAs. One of the MITEs is a novel class, but another MITE is related to the maize Stowaway family and is widely represented in Triticeae express sequence tags (ESTs). Flanking DNA of the longest sequence, a 20 425-bp fragment including and surrounding the HMW-glutenin Bx7 gene, showed additional cereal gene-like sequences both immediately 5' and 3' to the HMW-glutenin coding region. The transcriptional activities of sequences related to these flanking putative genes and the retrotransposon-related regions were indicated by matches to wheat and other Triticeae ESTs. Predictive analysis of matrix-attachment regions (MARs) of the HMW glutenin and several alpha-, gamma-, and omega-gliadin flanking DNAs indicate potential MARs immediately flanking each of the genes. Matrix binding activity in the predicted regions was confirmed for two of the HMW-glutenin genes.


Asunto(s)
Elementos Transponibles de ADN/genética , ADN de Plantas/genética , Glútenes/análogos & derivados , Glútenes/genética , Matriz Nuclear/metabolismo , Triticum/genética , Región de Flanqueo 3'/genética , Región de Flanqueo 5'/genética , Secuencia de Bases , Clonación Molecular , Secuencia Conservada , Bases de Datos Genéticas , Evolución Molecular , Etiquetas de Secuencia Expresada , Genes de Plantas , Glútenes/química , Datos de Secuencia Molecular , Peso Molecular , Análisis de Secuencia de ADN , Secuencias Repetidas Terminales , Transcripción Genética
10.
Artículo en Inglés | MEDLINE | ID: mdl-11569659

RESUMEN

A woman with complete vaginal eversion was found to have a large pelvic mass, extending from the rectovaginal septum to the presacral space. This 66-year-old woman with posthysterectomy vaginal eversion complained of pelvic fullness. A pessary provided relief of the prolapse, but the symptom of fullness persisted. Physical examination did not identify a pelvic mass. Computed tomography (CT) and magnetic resonance imaging (MRI) demonstrated a 9 cm tumor of the rectovaginal septum, extending to the presacral space. At laparotomy the patient had a massive neurofibroma arising from the anterior rectal wall. This case is of interest because the complete vaginal prolapse obscured the diagnosis of this large pelvic tumor. CT and MRI were useful in identifying and characterizing the mass. To our knowledge, this is the first reported case of vaginal prolapse with a large pelvic mass.


Asunto(s)
Histerectomía/efectos adversos , Neurofibroma/diagnóstico por imagen , Neurofibroma/patología , Neoplasias Retroperitoneales/diagnóstico por imagen , Neoplasias Retroperitoneales/patología , Prolapso Uterino/complicaciones , Prolapso Uterino/etiología , Anciano , Femenino , Humanos , Neurofibroma/complicaciones , Pesarios , Radiografía , Neoplasias Retroperitoneales/complicaciones
11.
J Pediatr Gastroenterol Nutr ; 27(2): 161-5, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9702646

RESUMEN

BACKGROUND: Like adults, children often experience anxiety associated with medical procedures. The purpose of this study was to investigate the effects of a program of psychological preparation for children undergoing endoscopy. METHODS: Sixty patients aged 6 to 19 years (mean, 12.2 years) were randomized into one of two groups. Group 1 received routine preparation before endoscopy. Group 2 received psychological preparation consisting of demonstration of materials that would be encountered during the procedure, use of a doll as a model, or use of a book with photographs of a child who had previously undergone endoscopy. Patients in both groups completed the Spielberger State-Trait Anxiety Inventory in the clinic and just before endoscopy. The Observational Scale of Behavioral Distress was completed by a blinded observer during each procedure. The attending physician (blinded) assessed patient cooperation. Vital signs were recorded in clinic and just before endoscopy. Parents and patients completed questionnaires after endoscopy. RESULTS: Analysis of the Spielberger State-Trait Anxiety Inventory showed patients in group 2 were significantly less anxious before endoscopy (p < 0.0001). They also required less meperidine (p < eq 0.04) per kilogram body weight and were more cooperative during the examination (p = 0.042). There was significantly less autonomic nervous system stimulation in those who had undergone psychological preparation (change in heart rate, p < 0.001; change in systolic blood pressure, p = 0.04). Statistically significant differences were found in the patients' response to questions after endoscopy regarding perceived anxiety during the procedure (p = 0.003) and the parents' response to questions regarding their own conditions (p = 0.026) and that of their child (p < 0.001). CONCLUSION: Psychological preparation before endoscopy significantly decreases patient and parental anxiety. Such preparation may allow for a reduction in sedative medications and thereby enhance procedural safety.


Asunto(s)
Ansiedad/prevención & control , Endoscopía Gastrointestinal/psicología , Gastroscopía/psicología , Educación del Paciente como Asunto , Adolescente , Adulto , Ansiedad/fisiopatología , Presión Sanguínea , Niño , Frecuencia Cardíaca , Humanos , Encuestas y Cuestionarios
12.
Am J Bot ; 85(1): 30, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21684877

RESUMEN

The potential for seed banks to significantly affect the genetic structure of populations was recognized nearly two decades ago. However, there has been little empirical work that examines the problem. In this study, we explore the possibility that the seed bank of a rare annual, Clarkia springvillensis, could act as a buffer against the genetic consequences of small population size. We examined the adult and seed bank cohort in three natural populations. The seed bank was surveyed by collecting soil cores twice during the growing season: postgermination and post seed set. The genetic constitution of the adults and seed bank cohort was determined by examining eight polymorphic isozyme loci via starch gel electrophoresis. The total genetic diversity in the seed bank (Ht = 0.355) was significantly higher than in the adults (Ht = 0.260). Additionally, Fst estimates of genetic differentiation among populations showed significantly less differentiation among population seed banks (Fst = 0.008) than among adults (Fst = 0.045). These results are in agreement with the expectation that seed banks would act to maintain genetic diversity in populations as well as have the effect of slowing differentiation of populations.

13.
J Biol Chem ; 270(9): 4721-8, 1995 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-7876244

RESUMEN

The Schizosaccharomyces pombe hmt1 gene encodes an ABC (ATP-binding cassette)-type protein essential for Cd2+ tolerance. Immunoblot analysis of subcellular fractions indicates that the native HMT1 polypeptide is associated with the vacuolar membrane. Vacuolar membrane vesicles were purified from strains that hyperproduce, or are deficient in, the HMT1 protein. In vitro transport of radiolabeled substrates by these vesicles indicates that HMT1 is an ATP-dependent transporter of phytochelatins, the metal-chelating peptides involved in heavy metal tolerance of plants and certain fungi. Vacuolar vesicles containing HMT1 are capable of taking up both apo-phytochelatins and phytochelatin-Cd2+ complexes. HMT1 activity is sensitive to antibodies directed against this protein and to vanadate, but not to inhibitors affecting the vacuolar proton ATPase or ionophores that abolish the pH gradient across the vacuolar membrane. Vacuolar uptake of Cd2+ and of a glutathione conjugate were also observed, but are not attributable to HMT1. These studies highlight the importance of the yeast vacuole in detoxification of xenobiotics.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Metales/metabolismo , Péptidos/metabolismo , Schizosaccharomyces/metabolismo , Transportadoras de Casetes de Unión a ATP/genética , Sitios de Unión , Transporte Biológico , Calcio/metabolismo , Cisteína/metabolismo , ADN Complementario , Glutatión/análogos & derivados , Glutatión/metabolismo , Metaloproteínas/metabolismo , Fitoquelatinas , Proteínas de Plantas/metabolismo , Biosíntesis de Proteínas , Transcripción Genética , Vacuolas/metabolismo
14.
Planta ; 193(2): 155-62, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7764986

RESUMEN

Certain higher plants synthesize and accumulate glycine betaine, a compound with osmoprotectant properties. Biosynthesis of glycine betaine proceeds via the pathway choline-->betaine aldehyde-->glycine betaine. Plants such as tobacco (Nicotiana tabacum L.) which do not accumulate glycine betaine lack the enzymes catalyzing both reactions. As a step towards engineering glycine betaine accumulation into a non-accumulator, spinach and sugar beet complementary-DNA sequences encoding the second enzyme of glycine-betaine synthesis (betaine aldehyde dehydrogenase, BADH, EC 1.2.1.8) were expressed in tobacco. Despite the absence of a typical transit peptide, BADH was targeted to the chloroplast in leaves of transgenic plants. Levels of extractable BADH were comparable to those in spinach and sugar beet, and the molecular weight, isoenzyme profile and Km for betaine aldehyde of the BADH enzymes from transgenic plants were the same as for native spinach or sugar beet BADH. Transgenic plants converted supplied betaine aldehyde to glycine betaine at high rates, demonstrating that they were able to transport betaine aldehyde across both the plasma membrane and the chloroplast envelope. The glycine betaine produced in this way was not further metabolized and reached concentrations similar to those in plants which accumulate glycine betaine naturally. Betaine aldehyde was toxic to non-transformed tobacco tissues whereas transgenic tissues were resistant due to detoxification of betaine aldehyde to glycine betaine. Betaine aldehyded ehydrogenase is therefore of interest as a potential selectable marker, as well as in the metabolic engineering of osmoprotectant biosynthesis.


Asunto(s)
Aldehído Oxidorreductasas/metabolismo , Betaína , Betaína/análogos & derivados , Cloroplastos/metabolismo , Nicotiana/metabolismo , Plantas Tóxicas , Aldehído Oxidorreductasas/genética , Secuencia de Aminoácidos , Betaína/metabolismo , Betaína/farmacología , Betaína Aldehído Deshidrogenasa , Transporte Biológico , Clonación Molecular , Resistencia a Medicamentos , Datos de Secuencia Molecular , Plantas Modificadas Genéticamente , Señales de Clasificación de Proteína/metabolismo , ARN Mensajero/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Nicotiana/genética , Verduras
15.
Arch Biochem Biophys ; 304(2): 392-401, 1993 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-8346915

RESUMEN

In plants and in certain fungi, exposure to heavy metals induces the synthesis of metal-binding peptides commonly known as phytochelatins. With cadmium, phytochelatins can sequester the metal into a sulfide-containing complex. From genetic analysis of fission yeast mutants, we previously reported that two genes in purine biosynthesis, encoding adenylosuccinate synthetase and succinoaminoimidazole carboxamide ribonucleotide (SAICAR) synthetase, are required for the biogenesis of the phytochelatin-cadmium-sulfide complex in vivo. We suggested that a sulfur analog of aspartate, cysteine sulfinate, might be utilized by these enzymes and that the cysteine sulfinate-derived products would then become intermediates or carriers in a sulfur transfer pathway leading to the sulfide found within the metal chelate. In this paper, we report that partially purified adenylosuccinate synthetase and SAICAR synthetase are capable of utilizing cysteine sulfinate in vitro to form sulfur analog products. Adenylosuccinate lyase, however, fails to catalyze further conversion of these sulfur derivatives. These observations support the genetic data implicating a link among purine biosynthetic enzymes, sulfur metabolism, and cadmium tolerance.


Asunto(s)
Adenilosuccinato Liasa/metabolismo , Adenilosuccinato Sintasa/metabolismo , Cadmio/metabolismo , Cisteína/análogos & derivados , Schizosaccharomyces/metabolismo , Adenilosuccinato Liasa/aislamiento & purificación , Adenilosuccinato Sintasa/aislamiento & purificación , Sistema Libre de Células , Cisteína/metabolismo , Farmacorresistencia Microbiana , Neurotransmisores , Péptido Sintasas/metabolismo , Schizosaccharomyces/enzimología
16.
Plant Physiol ; 98(2): 761-3, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16668708

RESUMEN

Light and fungal elicitor induce mRNA encoding 3-deoxy-d-arabino-heptulosonate 7-phosphate (DAHP) synthase in suspension cultured cells of parsley (Petroselinum crispum L.). The kinetics and dose response of mRNA accumulation were similar for DAHP synthase and phenylalanine ammonia-lyase (PAL). Six micrograms of elicitor from Phytophthora megasperma f. glycinia gave a detectable induction within 1 hour. Induction of DAHP synthase and PAL mRNAs by light was transient, reaching maximal levels at 4 hours and returning to pretreatment levels after 24 hours. Our data suggest that either light or fungal elicitor transcriptionally activate DAHP synthase. A coordinate regulation for key enzymes in the synthesis of primary and secondary metabolites is indicated.

17.
Plant Mol Biol ; 18(1): 1-11, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1731961

RESUMEN

Members of the Chenopodiaceae, such as sugar beet and spinach, accumulate glycine betaine in response to salinity or drought stress. The last enzyme in the glycine betaine biosynthetic pathway is betaine aldehyde dehydrogenase (BADH). In sugar beet the activity of BADH was found to increase two- to four-fold in both leaves and roots as the NaCl level in the irrigation solution was raised from 0 to 500 mM. This increase in BADH activity was paralleled by an increase in level of translatable BADH mRNA. Several cDNAs encoding BADH were cloned from a lambda gt10 library representing poly(A+) RNA from salinized leaves of sugar beet plants, by hybridization with a spinach BADH cDNA. Three nearly full-length cDNA clones were confirmed to encode BADH by their nucleotide and deduced amino acid sequence identity to spinach BADH; these clones showed minor nucleotide sequence differences consistent with their being of two different BADH alleles. The clones averaged 1.7 kb and contained an open reading frame predicting a polypeptide of 500 amino acids with 83% identity to spinach BADH. RNA gel blot analysis of total RNA showed that salinization to 500 mM NaCl increased BADH mRNA levels four-fold in leaves and three-fold in the taproot. DNA gel blot analyses indicated the presence of at least two copies of BADH in the haploid sugar beet genome.


Asunto(s)
Aldehído Oxidorreductasas/genética , Regulación de la Expresión Génica/efectos de los fármacos , Proteínas de Plantas/genética , Plantas/enzimología , Cloruro de Sodio/farmacología , Aldehído Oxidorreductasas/química , Aldehído Oxidorreductasas/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Betaína/metabolismo , Betaína Aldehído Deshidrogenasa , Northern Blotting , Southern Blotting , Clonación Molecular , Datos de Secuencia Molecular , Sistemas de Lectura Abierta/genética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Pruebas de Precipitina
18.
Child Health Care ; 20(4): 248-9, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-10183581

RESUMEN

As pediatric care becomes more complex and technical, there is a continuing tendency among health care professionals from all fields to use labels, jargon, and abbreviations when talking about and talking to young patients. This article offers possible explanations for the use of labels and jargon, and provides a summary of the dangers inherent in this sort of communication. Simple suggestions for alternative forms of communication are provided.


Asunto(s)
Niño Hospitalizado/psicología , Barreras de Comunicación , Relaciones Profesional-Paciente , Terminología como Asunto , Niño , Humanos , Personal de Hospital/normas , Estados Unidos
19.
Plant Physiol ; 94(2): 507-10, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16667741

RESUMEN

Light treatment of suspension cultured cells of parsley (Petroselinum crispum) was shown to increase the activity of the shikimic acid pathway enzyme, 3-deoxy-d-arabino-heptulosonic acid-7-phosphate (DAHP) synthase (EC 4.1.2.15). DAHP synthase activity was assayed for two isoforms, DS-Mn and DS-Co (RJ Ganson, TA d'Amato, RA Jensen [1986] Plant Physiol 82: 203-210). Light increased the enzymatic activity of the plastidic isoform DS-Mn as much as 2-fold, averaging 1.6-fold with >95% confidence. The cytosolic isoform DS-Co was unaffected. Cycloheximide and actinomycin D, translational and transcriptional inhibitors, respectively, both reversed induction of DS-Mn by light suggesting transcriptional regulation of the gene. Chorismate mutase activity was assayed for the two isoforms CM I and CM II (BK Singh, JA Connelly, EE Conn [1985] Arch Biochem Biophys 243: 374-384). Treatment by light did not significantly affect either chorismate mutase isoform. The ratio of the two chorismate mutase isoforms changed during the growth cycle, with an increase in the ratio of plastidic to cytosolic isoforms occurring towards the end of logarithmic growth.

20.
Ann Plast Surg ; 23(5): 450-5, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2690719

RESUMEN

Multiple hereditary lipomatosis has been reported very rarely in the literature. The largest number of lipomas previously reported in a single patient was 160. We report on a 45-year-old man who began to experience multiple lipomas at about age 26. The lipomas multiplied until they severely disfigured his entire torso, arms, and upper legs. Both sides of his body were affected to approximately equal degrees. A family history revealed that the patient's father, two brothers, and two nephews have all experienced multiple subcutaneous lipomas, although to a lesser degree. In treating the patient, what appeared to be very large lipomas were in fact found to be subcutaneous clusters of hundreds of small encapsulated lipomas. Lipomas were excised using suction lipectomy to treat different involved areas on eleven separate occasions. A total of 8,475 cc was removed over a two-year period. A modified, slightly less blunt cannula was developed to aspirate the clustered lipomas individually.


Asunto(s)
Lipomatosis/genética , Humanos , Lipectomía/métodos , Lipomatosis/patología , Lipomatosis/cirugía , Masculino , Persona de Mediana Edad
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