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1.
Plant J ; 104(5): 1382-1398, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33048402

RESUMEN

Plants cannot fix nitrogen directly; they must absorb it from the soil through their roots, or in rare cases, form associations with nitrogen-fixing bacteria. The efficiency of nitrogen use in most domesticated crops is low, and more than half of the available nitrogen in the soil can leach into the environment. Understanding the nitrogen signaling pathways is essential for maximizing the efficiency of nitrogen use in crops. In the present study, we characterized the Myeloblastosis (Myb)-like gene NITROGEN RESPONSE DEFICIENCY 1 (NID1). We observed that the growth performance of nid1 knockout (KO) mutant Arabidopsis plants was better than that of wild-type Col-0 plants under very low-nitrate conditions, leading to improved growth performance in the nid1 KO plants. The results of chromatin immunoprecipitation and electrophoretic mobility shift assays indicated that NID1 binds to the promoter of the NITRATE TRANSPORTER (NRT)1.1 gene. Furthermore, nid1 KO plants exhibited similar growth performance to the nid1 KO/chl1-5 (nrt1.1 KO) double mutant and chl1-5 (nrt1.1 KO) plants in response to low-nitrate conditions. We suggest that NID1 plays a crucial role as a transcription factor in optimizing plant growth by modulating the transcript abundance of the nitrate transceptor CHL1, leading to enhanced ABA accumulation in low-nitrate conditions.


Asunto(s)
Proteínas de Transporte de Anión/genética , Arabidopsis/crecimiento & desarrollo , Nitratos/metabolismo , Proteínas de Plantas/genética , Ácido Abscísico/metabolismo , Proteínas de Transporte de Anión/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Técnicas de Inactivación de Genes , Mutación , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
2.
J Eukaryot Microbiol ; 62(5): 637-49, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25912654

RESUMEN

Apusomonads comprise an understudied and undersampled group of heterotrophic flagellates that is closely related to opisthokonts, the supergroup containing animals and fungi. We cultured representatives of a new clade of apusomonads, Chelonemonas n. gen., which is sister to marine forms of Thecamonas in SSU rRNA gene phylogenies. Scanning electron microscopy shows that members of Chelonemonas have a hexagonal patterning to their submembranous pellicle, which is not known to exist in other apusomonads. We propose that the subfamily Thecamonadinae refer to the marine Thecamonas/Chelonomonas clade. We also report two new strains of Multimonas, one of which is genetically divergent from previously described strains, and here described as a new species, Multimonas koreensis. Both strains of Multimonas have appendages on their dorsal surface that could be extrusomes, and a frilled appearance to the border of their pellicle. Explorations of taxon sampling in SSU rRNA gene phylogenies confirm the new strains' evolutionary affinities, but do not resolve relationships among the five main apusomonad clades. These phylogenies also separate the freshwater species "Thecamonas" oxoniensis from the marine members of the genus Thecamonas. The new strains described here may provide valuable genetic and morphological data for evaluating the relationships and evolution of apusomonads.


Asunto(s)
Eucariontes/clasificación , Eucariontes/aislamiento & purificación , Animales , Evolución Biológica , Eucariontes/citología , Eucariontes/genética , Genes de ARNr , Variación Genética , Procesos Heterotróficos , Microscopía Electrónica de Rastreo , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 18S , Análisis de Secuencia de ADN
3.
Trop Med Int Health ; 17(12): 1534-43, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23051841

RESUMEN

OBJECTIVES: To investigate the magnitude and characteristics of the economic burden resulting from acute pesticide poisoning (APP) in South Korea. METHODS: The total costs of APP from a societal perspective were estimated by summing the direct medical and non-medical costs together with the indirect costs. Direct medical costs for patients assigned a disease code of pesticide poisoning were extracted from the Korean National Health Insurance Reimbursement Data. Direct non-medical costs were estimated using the average transportation and caregiving costs from the Korea Health Panel Survey. Indirect costs, incurred by pre-mature deaths and work loss, were obtained using 2009 Life Tables for Korea and other relevant literature. RESULTS: In 2009, a total of 11,453 patients were treated for APP and 1311 died, corresponding to an incidence of 23.1 per 100,000 population and a mortality rate of 2.6 per 100,000 population in South Korea. The total costs of APP were estimated at approximately US$ 150 million, 0.3% of the costs of total diseases. Costs due to pre-mature mortality accounted for 90.6% of the total costs, whereas the contribution of direct medical costs was relatively small. CONCLUSION: Costs from APP demonstrate a unique characteristic of a large proportion of the indirect costs originating from pre-mature mortality. This finding suggests policy implications for restrictions on lethal pesticides and safe storage to reduce fatality and cost due to APP.


Asunto(s)
Costo de Enfermedad , Plaguicidas/envenenamiento , Adolescente , Adulto , Distribución por Edad , Anciano , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Tablas de Vida , Masculino , Persona de Mediana Edad , Modelos Econométricos , Mortalidad Prematura , Enfermedades Profesionales/economía , Enfermedades Profesionales/epidemiología , Intoxicación/economía , Intoxicación/epidemiología , Intoxicación/mortalidad , República de Corea/epidemiología , Suicidio/economía , Suicidio/estadística & datos numéricos
4.
Trop Med Int Health ; 16(8): 923-8, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21481110

RESUMEN

Thrombospondin-related adhesive protein (TRAP) from Plasmodium vivax (P. vivax) became one of the important vaccine candidates for malaria, because P. vivax TRAP (PvTRAP) is responsible for the sporozoite-host interactions. PvTRAP polymorphisms in the isolates from Republic of Korea (ROK) were analysed, setting the valuable baseline data for the future vaccine developments and clinical trials with PvTRAP, as a strong vaccine candidate. A total of 54 isolates were collected in 2010. PvTRAP genes from above isolates were amplified and sequenced, and the results were analysed and compared against Sal-1 strain. Sequencing analysis of 1424-bp-size PvTRAP PCR products revealed one major allelic type with six non-synonymous substitutions, where S81T, E95D, I121V and T127R substitutions were found in region II, and K371N and A425E substitutions from region IV. The ROK isolates revealed the limited sequence polymorphisms in PvTRAP in comparison with the reported isolates from other nations.


Asunto(s)
Genes Protozoarios/genética , Malaria Vivax/genética , Plasmodium vivax/aislamiento & purificación , Proteínas Protozoarias/genética , Animales , Secuencia Conservada/genética , Humanos , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , República de Corea , Vacunas/genética
5.
Protist ; 158(3): 397-413, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17576098

RESUMEN

Although Pleurostomum was described almost a century ago, flagellates assigned to this taxon have been recorded only in very occasional faunistic studies of highly saline habitats, and their phylogenetic position has remained uncertain. We report the cultivation, ultrastructure, and phylogenetic relationships of Pleurostomum flabellatum isolated from a Korean saltern pond of 313 per thousand salinity. This isolate is biflagellated with a cytostomal groove, and is not distinguishable from previous accounts of P. flabellatum from saturated brines in India and Australia. Pleurostomum flabellatum shows ultrastructural features characteristic of many Heterolobosea: (1) a striated rhizoplast, (2) an absence of stacked Golgi bodies, (3) parallel basal bodies and flagella, and (4) a large number of peripheral microtubules supporting a rostrum. 18S rRNA gene phylogenies strongly confirm the affinities of P. flabellatum within Heterolobosea. Furthermore, the 18S rRNA gene of P. flabellatum has the heterolobosean-specific helix 17_1, and a group I intron in the same position as in Acrasis rosea. Within Heterolobosea, the 'amoeboflagellate' genera Naegleria and Willaertia were its closest relatives with high bootstrap support and posterior probability. P. flabellatum was observed only as a flagellate, and never as an amoeba. Since light microscopy and electron microscopy observations indicate that P. flabellatum flagellates are capable both of feeding and division, there might be no amoeba stage. Being morphologically distinct from its closest relatives and phylogenetically distant from other flagellate-only Heterolobosea, P. flabellatum cannot be moved into any previously described heterolobosean genus. Instead, we move Pleurostomum into Heterolobosea, and assign as the type species Pleurostomum salinum Namyslowski 1913, a species that closely resembles P. flabellatum. The optimal temperature for growth of P. flabellatum is 40 degrees C. Interestingly, P. flabellatum grows optimally at 300 per thousand salinity and fails to grow below 200 per thousand salinity, indicating that it is an 'extreme halophile'. The optimal salinity for growth is the highest for any eukaryote examined to date.


Asunto(s)
Eucariontes/clasificación , Eucariontes/aislamiento & purificación , Agua/parasitología , Animales , ADN Protozoario/química , ADN Protozoario/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Eucariontes/genética , Eucariontes/ultraestructura , Genes de ARNr , Intrones , Corea (Geográfico) , Microscopía Electrónica de Transmisión , Datos de Secuencia Molecular , Orgánulos/ultraestructura , Filogenia , ARN Protozoario/genética , ARN Ribosómico 18S/genética , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico , Cloruro de Sodio/metabolismo , Temperatura
6.
J Med Entomol ; 39(1): 244-7, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11931266

RESUMEN

As part of an on-going malaria surveillance effort conducted by the U.S. Forces Korea, Republic of Korea (ROK), a total of 28,286 anopheline mosquitoes was tested for the presence of Plasmodium vivax circumsporozoite (CS) protein. Mosquitoes were collected (using a variety of light and baited traps) from 29 locations throughout the ROK (the majority were collected near the de-militarized zone), identified to species, and tested by enzyme-linked immunosorbent assay for the presence of P. vivax 210 and P. vivax 247 CS protein. Recent evidence suggests that characters used to separate Anopheles sinensis Wiedemann from An. lesteri Baisas & Hu are unreliable; therefore, the data have been analyzed by grouping these two species. A total of 25,365 Anopheles sinensis/lesteri, 2,890 An. yatsushiroensis Miyazaki, and 31 An. sineroides Yamada was tested. Of these, one pool of 10 An. sinensis/lesteri collected on 9 September 1999 at Camp Howze and one pool of nine An. sinensis/ lesteri collected on 13 September 1999 at Camp Bonifas were positive for P. vivax 247.


Asunto(s)
Culicidae/parasitología , Plasmodium vivax/aislamiento & purificación , Animales , Antígenos de Protozoos/análisis , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Corea (Geográfico) , Plasmodium vivax/inmunología , Proteínas Protozoarias/análisis
7.
J Laparoendosc Adv Surg Tech A ; 13(5): 317-9, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14617390

RESUMEN

OBJECTIVES: To determine the presence or absence of air in the renal collecting system 48 hours following percutaneous nephrolithotomy (PCNL). METHODS: The study was based on a review of the records of the last 100 consecutive patients undergoing PCNL for stone extraction. Two urologists and a uroradiologist reviewed post-PCNL nephrostogram films and determined the presence or absence of air in the urinary tract. RESULTS: Nephrostography was routinely performed 48 hours after PCNL, and all films of the 100 patients were reviewed. Gas was detected in 98 (98%) of the 100 cases that appeared as gas pyelograms outlining the renal calyces. Of the 98 cases, 33 (34%) demonstrated gas in the upper calyx, 10 (10%) in the middle calyx, 12 (13%) in the lower calyx, and 43 (44%) in more than one calyx. Gas was not detected in the renal parenchyma or perirenal areas. CONCLUSIONS: Gas is present within the renal collecting system 48 hours after a percutaneous procedure. Prospective studies should be performed to document the amount of time needed for complete resolution of gas from the collecting system.


Asunto(s)
Embolia Aérea/etiología , Cálculos Renales/cirugía , Túbulos Renales Colectores/patología , Nefrostomía Percutánea , Complicaciones Posoperatorias/etiología , Adulto , Anciano , Anciano de 80 o más Años , Extravasación de Materiales Terapéuticos y Diagnósticos/etiología , Extravasación de Materiales Terapéuticos y Diagnósticos/cirugía , Femenino , Humanos , Complicaciones Intraoperatorias/etiología , Complicaciones Intraoperatorias/cirugía , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
8.
Pflugers Arch ; 447(3): 345-55, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14556075

RESUMEN

The regulation of skeletal muscle regeneration and growth in response to functional overload is a coordinated interaction of mechanical and endocrine signaling pathways. This study's purpose was to determine if RhoA expression and activity in rat plantaris muscle was induced by functional overload with or without anabolic steroid administration. Male Sprague Dawley (125 g) rats were subjected to bilateral ablation of the gastrocnemius muscle for 3 and 21 days and treated with nandrolone decanoate (ND, 6 mg/kg b.w.) or sesame seed oil injections. Western blot analysis revealed that RhoA protein expression was induced 2.1-fold by overload and 1.9-fold by ND at 3 days. RhoA protein remained elevated by overload after 21 days (3.8-fold). In addition, RhoA protein expression in C2C12 myotubes was induced after 18 h of 1% (1.8-fold) or 2% (2.2-fold) chronic radial stretch. Competitive RT PCR revealed that RhoA mRNA concentration increased 1.9-fold with ND, 2.9-fold with overload, and 11.8-fold with overload and ND administration when compared to sham at 3 days, indicating pre-translational control of RhoA by ND and a synergism between ND and overload to up-regulate RhoA mRNA. The ratio of RhoA protein associated with the muscle membrane fraction, an indicator of RhoA activity, increased 3.7-fold after 3 days of overload compared to controls. Although ND with overload (3.8-fold) produced a larger induction of RhoA protein than overload alone, the ratio of RhoA protein associated with the membrane fraction was not altered by ND treatment at 3 days. In conclusion, RhoA is an integrator of both mechanical and growth factor signaling whose expression and activity are increased by the combination of anabolic steroid and functional overload treatments in rat plantaris muscle.


Asunto(s)
Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Nandrolona/análogos & derivados , Nandrolona/farmacología , Proteína de Unión al GTP rhoA/biosíntesis , Animales , Hipertrofia/metabolismo , Masculino , Atrofia Muscular/metabolismo , Nandrolona Decanoato , Ratas , Ratas Sprague-Dawley , Proteína de Unión al GTP rhoA/genética
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