Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
Más filtros










Intervalo de año de publicación
1.
World J Gastrointest Surg ; 16(6): 1582-1591, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38983354

RESUMEN

BACKGROUND: Intraoperative persistent hypotension (IPH) during pancreaticoduodenectomy (PD) is linked to adverse postoperative outcomes, yet its risk factors remain unclear. AIM: To clarify the risk factors associated with IPH during PD, ensuring patient safety in the perioperative period. METHODS: A retrospective analysis of patient records from January 2018 to December 2022 at the First Affiliated Hospital of Nanjing Medical University identified factors associated with IPH in PD. These factors included age, gender, body mass index, American Society of Anesthesiologists classification, comorbidities, medication history, operation duration, fluid balance, blood loss, urine output, and blood gas parameters. IPH was defined as sustained mean arterial pressure < 65 mmHg, requiring prolonged deoxyepinephrine infusion for > 30 min despite additional deoxyepinephrine and fluid treatments. RESULTS: Among 1596 PD patients, 661 (41.42%) experienced IPH. Multivariate logistic regression identified key risk factors: increased age [odds ratio (OR): 1.20 per decade, 95% confidence interval (CI): 1.08-1.33] (P < 0.001), longer surgery duration (OR: 1.15 per additional hour, 95%CI: 1.05-1.26) (P < 0.01), and greater blood loss (OR: 1.18 per 250-mL increment, 95%CI: 1.06-1.32) (P < 0.01). A novel finding was the association of arterial blood Ca2+ < 1.05 mmol/L with IPH (OR: 2.03, 95%CI: 1.65-2.50) (P < 0.001). CONCLUSION: IPH during PD is independently associated with older age, prolonged surgery, increased blood loss, and lower plasma Ca2+.

2.
Front Plant Sci ; 10: 1118, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31552080

RESUMEN

Seed germination and formation are the beginning and ending, respectively, of a plant life cycle. These two processes are under fine regulation by the internal genetic information. Previously, we demonstrated that Arabidopsis MIDASIN 1 (MDN1) is required for ribosome biogenesis, and its dysfunction leads to pleiotropic developmental phenotypes, including impaired embryogenesis and slow seed germination. In this study, we further found that the weak mutant of MDN1, mdn1-1, exhibits an increased seed size phenotype. Seed proteomic analysis reveals that a number of proteins involved in seed development and response to external environments are mis-regulated by the MDN1 dysfunction. Many 2S seed storage proteins (SSPs) and late embryogenesis abundant (LEA) proteins are over-accumulated in the dry seeds of mdn1-1. Further, some genes encoding seed storage reserves are also upregulated in mdn1-1 seedlings. More interestingly, abscisic acid-insensitive 5 (ABI5) is over-accumulated in mdn1-1 seeds, and the loss of its function partially rescues the low seed germination rate of mdn1-1. Together, this study further demonstrates that MDN1 is essential for establishing a normal seed proteome, and its mutation triggers ABI5-mediated repression of seed germination.

3.
Nano Lett ; 19(9): 6454-6460, 2019 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-31424943

RESUMEN

We report on the first successful growth of wurtzite (WZ) GaBiAs nanowires (NWs) and reveal the effects of Bi incorporation on the electronic band structure by using polarization-resolved optical spectroscopies performed on individual NWs. Experimental evidence of a decrease in the band-gap energy and an upward shift of the topmost three valence subbands upon the incorporation of Bi atoms is provided, whereas the symmetry and ordering of the valence band states remain unchanged, that is, Γ9, Γ7, and Γ7 within the current range of Bi compositions. The extraordinary valence band structure of WZ GaBiAs NWs is explained by anisotropic hybridization and anticrossing between p-like Bi states and the extended valence band states of host WZ GaAs. Moreover, the incorporation of Bi into GaAs is found to significantly reduce the temperature sensitivity of the band-gap energy in WZ GaBiAs NWs. Our work therefore demonstrates that utilizing dilute bismide alloys provides new avenues for band-gap engineering and thus photonic engineering with NWs.

4.
Plant Physiol ; 180(1): 289-304, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30755475

RESUMEN

Ribosome biogenesis is an orchestrated process that relies on many assembly factors. The AAA-ATPase Midasin 1 (Mdn1) functions as a ribosome assembly factor in yeast (Saccharomyces cerevisiae), but the roles of MDN1 in Arabidopsis (Arabidopsis thaliana) are poorly understood. Here, we showed that the Arabidopsis null mutant of MDN1 is embryo-lethal. Using the weak mutant mdn1-1, which maintains viability, we found that MDN1 is critical for the regular pattern of auxin maxima in the globular embryo and functions in root meristem maintenance. By detecting the subcellular distribution of ribosome proteins, we noted that mdn1-1 impairs nuclear export of the pre-60S ribosomal particle. The processing of ribosomal precusor RNAs, including 35S, 27SB, and 20S, is also affected in this mutant. MDN1 physically interacts with PESCADILLO2 (PES2), an essential assembly factor of the 60S ribosome, and the observed mislocalization of PES2 in mdn1-1 further implied that MDN1 plays an indispensable role in 60S ribosome biogenesis. Therefore, the observed hypersensitivity of mdn1-1 to a eukaryotic translation inhibitor and high-sugar conditions might be associated with the defect in ribosome biogenesis. Overall, this work establishes a role of Arabidopsis MDN1 in ribosome biogenesis, which agrees with its roles in embryogenesis and root development.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiología , Chaperonas Moleculares/metabolismo , Proteínas Nucleares/metabolismo , Ribosomas/metabolismo , Semillas/crecimiento & desarrollo , ATPasas Asociadas con Actividades Celulares Diversas/genética , ATPasas Asociadas con Actividades Celulares Diversas/metabolismo , Arabidopsis/efectos de los fármacos , Proteínas de Arabidopsis/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proliferación Celular , Cicloheximida/farmacología , Ácidos Indolacéticos/metabolismo , Meristema/citología , Meristema/genética , Meristema/metabolismo , Chaperonas Moleculares/genética , Mutación , Proteínas Nucleares/genética , Células Vegetales , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Plantas Modificadas Genéticamente , Inhibidores de la Síntesis de la Proteína/farmacología , Procesamiento Postranscripcional del ARN , Semillas/genética , Semillas/metabolismo
5.
Biochem Biophys Res Commun ; 505(3): 712-719, 2018 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-30292412

RESUMEN

In Arabidopsis thaliana (Arabidopsis), Acetyl-CoA Carboxylase 2 (ACC2) is a nuclear DNA-encoded and plastid-targeted enzyme that catalyzes the conversion of acetyl-CoA to malonyl-CoA. ACC2 improves plant growth and development when chloroplast translation is impaired. However, little is known about the upstream signals that regulate ACC2. Here, through analyzing the transcriptome changes in brz-insensitive-pale green (bpg) 2-2, a pale-green mutant with impaired chloroplast gene expression resulting from loss of the BPG2 function, we found that the level of ACC2 was significantly up-regulated. Through performing genetic analysis, we further demonstrated that loss of the GENOMES UNCOUPLED 1 (GUN1) or GUN5 function partly perturbed the up-regulation of ACC2 in the bpg2-2 mutant, whereas ABA INSENSITIVE 4 (ABI4)-function-loss had no clear effect on the ACC2 expression. Furthermore, when plants were treated with plastid translation inhibitors, such as lincomycin and spectinomycin, the ACC2 transcriptional level was also markedly increased in a GUN-dependent manner. In conclusion, our results suggested that the GUN-involved plastid-to-nucleus retrograde communication played a role in regulating ACC2 in Arabidopsis.


Asunto(s)
Acetil-CoA Carboxilasa/genética , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Proteínas de Unión al ADN/genética , Liasas/genética , Transducción de Señal/genética , Acetil-CoA Carboxilasa/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al GTP/genética , Proteínas de Unión al GTP/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Liasas/metabolismo , Mutación , Plastidios/genética , Plastidios/metabolismo
6.
Rev Sci Instrum ; 88(10): 106103, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29092464

RESUMEN

A modified optics based technique was developed to effectively suppress spurious background signals encountered in the photoreflectance (PR) spectra obtained from bulk semiconductors and semiconductor microstructures. Based on a traditional PR setup, the novel PR approach utilized an achromatic beam reduction system to narrow the profile of a probe beam, which was subsequently collected by a focus lens coupled with an iris. The new setup guarantees high collection efficiency for probe signals and strong suppression of background signals. Compared with existing PR methods for background minimization, the proposed PR technique is simpler to accomplish, more cost effective, and provides a higher signal-to-noise ratio for the PR spectra.

7.
Sci Rep ; 6: 36446, 2016 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-27824150

RESUMEN

MDN1/Rea1, as an AAA-type ATPase, is predicted to be the largest protein involved in pre-ribosome maturation in most organisms. However, its function in plant growth and development is poorly understood. Here, we characterized a novel Arabidopsis mutant, dwarf &short root (dsr) 1, which shows pleiotropic developmental phenotypes, such as slow germination, short root, dwarf shoot, and reduced seed set under normal growth conditions. Using positional cloning, we revealed that the AtMDN1 function is impaired by a 'glutamic acid' to 'lysine' change at position 3838 of the amino acid sequence in dsr1. Multiple sequence alignment analysis revealed that the mutated Glu residue, which located in the linker domain of AtMDN1, is extremely conserved among organisms. AtMDN1 is expressed in various tissues, particularly in the shoot apex and root tip. Moreover, the results of transcript profile analyses showed that the dysfunction of AtMDN1 in dsr1 impairs the expression of genes related to plant growth and development, which is tightly associated with the pleiotropic phenotypes of dsr1. Thus, we concluded that the Glu residue plays a vital role in maintaining AtMDN1 functions, which are essential for plant growth and development.


Asunto(s)
ATPasas Asociadas con Actividades Celulares Diversas/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , ATPasas Asociadas con Actividades Celulares Diversas/química , ATPasas Asociadas con Actividades Celulares Diversas/genética , Secuencia de Aminoácidos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Germinación , Mutagénesis Sitio-Dirigida , Fenotipo , Raíces de Plantas/metabolismo , Brotes de la Planta/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Plantas Modificadas Genéticamente/metabolismo , ARN de Planta/química , ARN de Planta/aislamiento & purificación , ARN de Planta/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ARN , Transcriptoma
8.
Appl Opt ; 50(31): G98-G103, 2011 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-22086056

RESUMEN

A dispersion tailoring scheme for obtaining slow light in a silicon-on-insulator W1-type photonic crystal waveguide, novel to our knowledge, is proposed in this paper. It is shown that, by simply shifting the first two rows of air holes adjacent to the waveguide to specific directions, slow light with large group-index, wideband, and low group-velocity dispersion can be realized. Defining a criterion of restricting the group-index variation within a ±0.8% range as a flattened region, we obtain the ultraflat slow light with bandwidths over 5.0, 4.0, 2.5, and 1.0 nm when keeping the group index at 38.0, 48.8, 65.2, and 100.4, respectively. Numerical simulations are performed utilizing the three-dimensional (3D) plane-wave expansion method and the 3D finite-difference time-domain method.

9.
J Biosci ; 36(2): 223-8, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21654076

RESUMEN

Late embryogenesis abundant (LEA) protein family is a large protein family that includes proteins accumulated at late stages of seed development or in vegetative tissues in response to drought, salinity, cold stress and exogenous application of abscisic acid. In order to isolate peanut genes, an expressed sequence tag (EST) sequencing project was carried out using a peanut seed cDNA library. From 6258 ESTs, 19 LEA-encoding genes were identified and could be classified into eight distinct groups. Expression of these genes in seeds at different developmental stages and in various peanut tissues was analysed by semi-quantitative RT-PCR. The results showed that expression levels of LEA genes were generally high in seeds. Some LEA protein genes were expressed at a high level in non-seed tissues such as root, stem, leaf, flower and gynophore. These results provided valuable information for the functional and regulatory studies on peanut LEA genes.


Asunto(s)
Arachis/genética , Perfilación de la Expresión Génica , Proteínas de Plantas/genética , Arachis/crecimiento & desarrollo , Etiquetas de Secuencia Expresada , Flores/genética , Flores/metabolismo , Regulación del Desarrollo de la Expresión Génica , Datos de Secuencia Molecular , Proteínas de Plantas/clasificación , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Tallos de la Planta/genética , Tallos de la Planta/metabolismo , Semillas/genética , Semillas/metabolismo , Análisis de Secuencia de ADN
10.
Chin Med J (Engl) ; 124(21): 3468-75, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22340160

RESUMEN

BACKGROUND: Endogenous hydrogen sulfide is a new neuromodulator which takes part in the regulation of central nervous system physiology and diseases. Whether endogenous hydrogen sulfide in the central nervous system regulates cardiovascular activity is not known. In the present study, we observed the hemodynamic changes of hydrogen sulfide or its precursor by intracerebroventricular injection, and investigate the possible roles of endogenous digitalis like factors and sympathetic activity in the regulation. METHODS: Ninety-four Sprague-Dawley rats underwent a right cerebroventricular puncture, then the hydrogen sulfide saturation buffer or its precursor injected by intrcerebroventricular catheter. A heperin-filled catheter was inserted into the right femoral artery or into the left ventricle, and changes of blood pressure or cardiac function recorded by a Powerlab/4S instrument. Phentolamine or metoprolol were pre-injected to observe the possible role in autonomic nerve activity. After rats were sacrificed, plasma was collected and endogenous digitalis-like factors were measured with a commercial radioimmunoassay kit. The aortic, cardiac sarcolemmal vesicles were isolated and the activity of Na(+)-K(+)-ATPase was measured as ouabain-sensitive ATP hydrolysis under maximal velocity conditions by measuring the release of inorganic phosphate from ATP. Unpaired Student's t test for two groups or analysis of variances (ANOVA) for multiple groups were used to compare the differences of the changes. RESULTS: Intracerebroventricular injection of hydrogen sulfide induced a transient hypotension, then dramatic hypertenive effects in a dose-dependent manner. Bolus injection of L-cysteine or beta- mercaptopyruvate also increased mean arterial pressure (P < 0.01), whereas hydroxylamine-a cystathionine beta synthase inhibitor decreased the arterial pressure (P < 0.01). Hydrogen sulfide and L-cysteine increased mean arterial pressure, left ventricular develop pressure and left-ventricle maximal rate of systolic and diastolic pressure; these functions were decreased by hydroxylamine (P < 0.01). Glibenclamide (a K(ATP) channel blocker) blocked the transient hypotensive effect, phentolamine (an alpha-adrenergic receptor blocker) blocked the hypertensive effect, and metoprolol (a selective beta 1 receptor blocker) blocked the positive inoptropic effect of central nervous system hydrogen sulfide. The endogenous digitalis-like factors in plasma were elevated (P < 0.01) after treatment with L-cysteine, association with decreasing Na(+)-K(+)-ATPase activity in cardiac or aortic sarcolemmal vesicles (P < 0.01). Hydroxylamine injection reduced the endogenous digitalis-like factors level in plasma association with increasing Na(+)-K(+)-ATPase activity in cardiac and aortic sarcolemmal vesicles. CONCLUSION: Central nervous system endogenous hydrogen sulfide upregulated mean arterial pressure and cardiac systolic function by activation of sympathetic nerves or release of endogenous digitalis-like factors.


Asunto(s)
Sistema Nervioso Central/metabolismo , Hemodinámica/efectos de los fármacos , Sulfuro de Hidrógeno/metabolismo , Sulfuro de Hidrógeno/farmacología , Animales , Western Blotting , Cardenólidos/metabolismo , Sistema Nervioso Central/efectos de los fármacos , Cistationina betasintasa/metabolismo , Cisteína/análogos & derivados , Cisteína/farmacología , Masculino , Radioinmunoensayo , Ratas , Ratas Sprague-Dawley , Saponinas/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Sulfurtransferasas/metabolismo
11.
FEMS Microbiol Lett ; 313(2): 120-6, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21062346

RESUMEN

Trichoderma spp. are well-known biocontrol agents because of their antimicrobial activity against bacterial and fungal phytopathogens. However, the biochemical mechanism of their antiviral activity remains largely unknown. In this study, we found that Trichokonins, antimicrobial peptaibols isolated from Trichoderma pseudokoningii SMF2, could induce defense responses and systemic resistance in tobacco (Nicotiana tabacum var. Samsun NN) against tobacco mosaic virus (TMV) infection. Local Trichokonin (100 nM) treatment led to 54% lesion inhibition, 57% reduction in average lesion diameter and 30% reduction in average lesion area in systemic tissue of tobacco compared with control, indicating that Trichokonins induced resistance in tobacco against TMV infection. Trichokonin treatment increased the production of reactive oxygen species and phenolic compounds in tobacco. Additionally, application of Trichokonins significantly increased activities of pathogenesis-related enzymes PAL and POD, and upregulated the expression of several plant defense genes. These results suggested that multiple defense pathways in tobacco were involved in Trichokonin-mediated TMV resistance. We report on the antivirus mechanism of peptaibols, which sheds light on the potential of peptaibols in plant viral disease control.


Asunto(s)
Antiinfecciosos/inmunología , Nicotiana/inmunología , Nicotiana/virología , Peptaiboles/inmunología , Virus del Mosaico del Tabaco/inmunología , Trichoderma/química , Antiinfecciosos/aislamiento & purificación , Perfilación de la Expresión Génica , Genes de Plantas , Peptaiboles/aislamiento & purificación , Fenoles/metabolismo , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/virología , Especies Reactivas de Oxígeno/metabolismo
12.
Genome ; 53(10): 832-9, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20962890

RESUMEN

Peanut (Arachis hypogaea L.) is one of the most important oil crops in the world. However, biotechnological based improvement of peanut is far behind many other crops. It is critical and urgent to establish the biotechnological platform for peanut germplasm innovation. In this study, a peanut seed cDNA library was constructed to establish the biotechnological platform for peanut germplasm innovation. About 17,000 expressed sequence tags (ESTs) were sequenced and used for further investigation. Among which, 12.5% were annotated as metabolic related and 4.6% encoded transcription or post-transcription factors. ESTs encoding storage protein and enzymes related to protein degradation accounted for 28.8% and formed the largest group of the annotated ESTs. ESTs that encoded stress responsive proteins and pathogen-related proteins accounted for 5.6%. ESTs that encoded unknown proteins or showed no hit in the GenBank nr database accounted for 20.1% and 13.9%, respectively. A total number of 5066 EST sequences were selected to make a cDNA microarray. Expression analysis revealed that these sequences showed diverse expression patterns in peanut seeds, leaves, stems, roots, flowers, and gynophores. We also analyzed the gene expression pattern during seed development. Genes that were upregulated (≥twofold) at 15, 25, 35, and 45 days after pegging (DAP) were found and compared with 70 DAP. The potential value of these genes and their promoters in the peanut gene engineering study is discussed.


Asunto(s)
Arachis/genética , Etiquetas de Secuencia Expresada , Perfilación de la Expresión Génica/métodos , Análisis de Secuencia de ADN , Arachis/crecimiento & desarrollo , Clonación Molecular , Productos Agrícolas/genética , Regulación del Desarrollo de la Expresión Génica , Biblioteca de Genes , Genes de Plantas , Análisis de Secuencia por Matrices de Oligonucleótidos , Semillas/genética , Semillas/crecimiento & desarrollo , Semillas/metabolismo , Análisis de Secuencia de ADN/métodos
13.
Electron. j. biotechnol ; 13(5): 6-7, Sept. 2010. ilus, tab
Artículo en Inglés | LILACS | ID: lil-591888

RESUMEN

Microsatellites, or simple sequence repeats (SSRs), in expressed sequence tags (ESTs) provide an opportunity for low cost SSR development. We looked for EST-SSRs in 403,511 ESTs (generated by 454 sequencing and representing 70,654 contigs and 52,082 singletons) from soybean globular stage embryos. Among 122,736 unique ESTs, 3,729 contained one or more SSRs. In total, 3,989 SSRs were identified including 304 mono, 1,374 di, 2,208 tri, 70 tetra, 13 penta and 20 hexanucleotide SSRs. Thirty three EST-SSRs were selected for primer design and polymorphism analysis using twenty soybean cultivars and one wild-type soybean. Successful amplification was obtained using 21 of these primer pairs, 11 of which detected polymorphisms in these soybean cultivars. These results demonstrated that 454 high throughput sequencing is a powerful tool for molecular marker development. From the 3,989 identified SSRs we expect to obtain a large number of makers with polymorphism among different soybean cultivars, which would be useful for analysis of genetic diversity and maker assisted selection in the soybean breeding programs.


Asunto(s)
Etiquetas de Secuencia Expresada , Glycine max/genética , Genes de Plantas , Marcadores Genéticos , Repeticiones de Microsatélite , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Análisis de Secuencia de ADN
14.
Electron. j. biotechnol ; 13(3): 7-8, May 2010. ilus, tab
Artículo en Inglés | LILACS | ID: lil-577102

RESUMEN

Making use of the gene resources of wild type peanuts is a way to increase the genetic diversity of the cultivars. Marker assisted selection (MAS) could shorten the process of inter-specific hybridization and provide a possible way to remove the undesirable traits. However, the limited number of molecular markers available in peanut retarded its MAS process. We started a peanut ESTs (Expressed Sequence Tags) project aiming at cloning genes with agronomic importance and developing molecular markers. In this study we found 610 ESTs that contained one or more SSRs from 12,000 peanut ESTs. The most abundant SSRs in peanut are trinucleotides (66.3 percent) SSRs and followed by dinucleotide (28.8 percent) SSRs. AG/TC (10.7 percent) repeat was the most abundant and followed by CT/GA (9.0 percent), CTT/GAA (7.4 percent), and AAG/TTC (7.3 percent) repeats. Ninety-four SSR containing ESTs were randomly selected for primer design and synthesis, of which 33 pairs could generate good amplification and were used for polymorphism assessment. Results showed that polymorphism was very low in cultivars, while high level of polymorphism was revealed in wild type peanuts.


Asunto(s)
Arachis/genética , Clonación Molecular , Etiquetas de Secuencia Expresada , Repeticiones de Microsatélite , ADN de Plantas/genética , Producción de Cultivos , Arachis/crecimiento & desarrollo , Secuencia de Bases , Marcadores Genéticos , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Selección Genética
15.
BMC Plant Biol ; 10: 3, 2010 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-20047695

RESUMEN

BACKGROUND: MicroRNAs (miRNAs) are a new class of small, endogenous RNAs that play a regulatory role in the cell by negatively affecting gene expression at the post-transcriptional level. miRNAs have been shown to control numerous genes involved in various biological and metabolic processes. There have been extensive studies on discovering miRNAs and analyzing their functions in model species, such as Arabidopsis and rice. Increasing investigations have been performed on important agricultural crops including soybean, conifers, and Phaselous vulgaris but no studies have been reported on discovering peanut miRNAs using a cloning strategy. RESULTS: In this study, we employed the next generation high through-put Solexa sequencing technology to clone and identify both conserved and species-specific miRNAs in peanuts. Next generation high through-put Solexa sequencing showed that peanuts have a complex small RNA population and the length of small RNAs varied, 24-nt being the predominant length for a majority of the small RNAs. Combining the deep sequencing and bioinformatics, we discovered 14 novel miRNA families as well as 75 conserved miRNAs in peanuts. All 14 novel peanut miRNAs are considered to be species-specific because no homologs have been found in other plant species except ahy-miRn1, which has a homolog in soybean. qRT-PCR analysis demonstrated that both conserved and peanut-specific miRNAs are expressed in peanuts. CONCLUSIONS: This study led to the discovery of 14 novel and 22 conserved miRNA families from peanut. These results show that regulatory miRNAs exist in agronomically important peanuts and may play an important role in peanut growth, development, and response to environmental stress.


Asunto(s)
Arachis/genética , MicroARNs/genética , ARN de Planta/genética , Clonación Molecular , Secuencia Conservada , Etiquetas de Secuencia Expresada , Genoma de Planta , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ARN
16.
J Biosci ; 34(2): 227-38, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19550039

RESUMEN

The cultivated peanut is a valuable source of dietary oil and ranks fifth among the world oil crops. Plant fatty acid biosynthesis is catalysed by type II fatty acid synthase (FAS) in plastids and mitochondria. By constructing a full-length cDNA library derived from immature peanut seeds and homology-based cloning, candidate genes of acyl carrier protein (ACP), malonyl-CoA:ACP transacylase, beta-ketoacyl-ACP synthase (I, II, III), beta-ketoacyl-ACP reductase, beta-hydroxyacyl-ACP dehydrase and enoyl-ACP reductase were isolated. Sequence alignments revealed that primary structures of type II FAS enzymes were highly conserved in higher plants and the catalytic residues were strictly conserved in Escherichia coli and higher plants. Homologue numbers of each type II FAS gene expressing in developing peanut seeds varied from 1 in KASII, KASIII and HD to 5 in ENR. The number of single-nucleotide polymorphisms (SNPs) was quite different in each gene. Peanut type II FAS genes were predicted to target plastids except ACP2 and ACP3. The results suggested that peanut may contain two type II FAS systems in plastids and mitochondria. The type II FAS enzymes in higher plants may have similar functions as those in E. coli.


Asunto(s)
Arachis/enzimología , Arachis/genética , Ácido Graso Sintasas/química , Ácido Graso Sintasas/genética , Secuencia de Aminoácidos , Clonación Molecular , Biología Computacional/métodos , ADN Complementario/metabolismo , Escherichia coli/metabolismo , Biblioteca de Genes , Mitocondrias/metabolismo , Modelos Biológicos , Datos de Secuencia Molecular , Plastidios/metabolismo , ARN/metabolismo , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido
17.
Opt Express ; 16(17): 13168-74, 2008 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-18711555

RESUMEN

We demonstrated a reflective-type liquid crystal (LC) intensity modulator in 1550 nm telecomm band. An effective way to compensate the residual phase of a LC cell is proposed. With the adjustment of a true zero-order quarter wave plate and enhanced by total internal reflection induced birefringence, over 53 dB dynamic range was achieved, which is much desired for some high-end optical communication, infrared scene projection applications. In addition, the driving voltages were decreased and adjustable. Mechanical and spectral tolerance measurements show that our LC modulator is quite stable. Further applications of our experimental setup were discussed including bio-sensors and high speed modulators.


Asunto(s)
Técnicas Biosensibles/instrumentación , Electrónica/instrumentación , Tecnología de Fibra Óptica/instrumentación , Cristales Líquidos/química , Procesamiento de Señales Asistido por Computador/instrumentación , Telecomunicaciones/instrumentación , Campos Electromagnéticos , Diseño de Equipo , Análisis de Falla de Equipo , Cristales Líquidos/efectos de la radiación
18.
Tree Physiol ; 25(2): 167-78, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15574398

RESUMEN

Acacia mangium Willd. is a legume tree species native to subtropical and tropical regions of Asia and Australia. Many features of its flower development are common to other legume tree species. To identify genes involved in its floral development, we constructed a subtractive flower cDNA library against vegetative tissues. The 1123 expressed sequence tags (ESTs) represented 576 unique genes. Macroarray analysis further identified 147 of these genes as specific to the early, late or whole flowering process. Eight percent of these flower-specific genes encode MADS-domain-containing transcription factors and MYB proteins. Four percent encode other transcription factors and 10% encode regulatory proteins such as G proteins, kinases and phosphatases. Flower-specific transcripts for gibberellic acid (GA) synthesis and GA-induced proteins, as well as other stress- and pathogenesis-related genes (9%), implicate their involvement in A. mangium flower development. Eighteen percent of the flower-specific genes encode hypothetical proteins and 18% encode proteins of unknown functions. The RNA blot hybridization confirmed and detailed the expression patterns of selected genes. Functions of the A. mangium flower-specific genes are discussed based on comparison with their Arabidopsis homologues, most of which have been implicated in Arabidopsis floral development. Our work suggests general conservation of floral development in A. mangium and Arabidopsis. Further characterization of the conserved and different flower-specific genes will delineate the flowering process of this important legume tree species and facilitate genetic modification of its reproduction.


Asunto(s)
Acacia/genética , Flores/genética , Árboles/genética , Genes de Plantas/genética , Hibridación de Ácido Nucleico/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN de Planta/genética
19.
Zhonghua Nan Ke Xue ; 9(8): 580-3, 2003 Nov.
Artículo en Chino | MEDLINE | ID: mdl-14689888

RESUMEN

OBJECTIVE: To investigate the efficacy of the double-balloon and triple-channel catheter (DBTC) in the treatment of chronic bacterial prostatitis (CBP). METHODS: One hundred and three CBP patients were randomly assigned to three different groups and received three different therapies, respectively: 1. 61 cases by transurethral perfusion and drainage with antibiotics with DBTC catheter; 2. 29 cases by intravenous antibiotics, and 3. 13 cases by transurethral irrigation with 0.9% saline. The lecithin, white blood cells (WBC) in expressed prostatic secretion (EPS) and Meares-Stamey's test fractionary urine culture pre- and post-therapies were compared. RESULTS: The improvement rates of clinical symptoms and lecithin corpuscles were 81.9% and 68.9%, respectively. And the decline rate of WBC and bacteriological efficacy rate were 75.4% and 91.8%, respectively. There was a significant statistical difference between the DBTC group and the intravenous group in the lecithin, WBC and bacterial culture (P < 0.05, < 0.01 and < 0.01, respectively), and so was there between the saline group and the intravenous group in the decline of WBC(chi 2 = 5.6, P < 0.05), but with no difference in lecithin and bacterial culture. Among 61 patients treated with DBTC, 3 developed mild allergic reaction in urethra. CONCLUSIONS: Transurethral DBTC has a better clinical efficacy than traditional intravenous treatment for CBP. DBTC perfusion combined with other hypurgia holds obvious advantages of being safe, effective, easy and repeatable in the treatment of CBP.


Asunto(s)
Infecciones Bacterianas/terapia , Cateterismo/métodos , Perfusión/métodos , Prostatitis/terapia , Adolescente , Adulto , Infecciones Bacterianas/complicaciones , Enfermedad Crónica , Humanos , Masculino , Persona de Mediana Edad , Próstata/microbiología , Prostatitis/microbiología
20.
J Environ Sci (China) ; 14(4): 524-9, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12491727

RESUMEN

The biodegradation of two acetanilide herbicides, acetochlor and butachlor in soil after other environmental organic matter addition were measured during 35 days laboratory incubations. The herbicides were applied to soil alone, soil-SDBS (sodium dodecylbenzene sulfonate) mixtures and soil-HA (humic acid) mixtures. Herbicide biodegradation kinetics were compared in the different treatment. Biodegradation products of herbicides in soil alone samples were identified by GC/MS at the end of incubation. Addition of SDBS and HA to soil decreased acetochlor biodegradation, but increased butachlor biodegradation. The biodegradation half-life of acetochlor and butachlor in soil alone, soil-SDBS mixtures and soil-HA mixtures were 4.6 d, 6.1 d and 5.4 d and 5.3 d, 4.9 d and 5.3 d respectively. The biodegradation products were hydroxyacetochlor and 2-methyl-6-ethylaniline for acetochlor, and hydroxybutachlor and 2,6-diethylaniline for butachlor.


Asunto(s)
Acetanilidas/metabolismo , Herbicidas/metabolismo , Microbiología del Suelo , Toluidinas/metabolismo , Bencenosulfonatos/metabolismo , Biodegradación Ambiental , Semivida , Sustancias Húmicas/metabolismo , Cinética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA