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For ultrasound multi-angle plane wave (PW) imaging, the coherent PW compounding (CPWC) method provides limited image quality because of its conventional delay-and-sum beamforming. The delay-multiply-and-sum (DMAS) method is a coherence-based algorithm that improves image quality by introducing signal coherence among either receiving channels or PW transmit angles into the image output. The degree of signal coherence in DMAS is conventionally a global value for the entire image and thus the image resolution and contrast in the target region improves at the cost of speckle quality in the background region. In this study, the adaptive DMAS (ADMAS) is proposed such that the degree of signal coherence relies on the local characteristics of the image region to maintain the background speckle quality and the corresponding contrast-to-noise ratio (CNR). Subsequently, the ADMAS algorithm is further combined with minimum variance (MV) beamforming to increase the image resolution. The optimal MV estimation is determined to be in the direction of the PW transmit angle (Tx) for multi-angle PW imaging. Our results show that, using the PICMUS dataset, TxMV-ADMAS beamforming significantly improves the image quality compared with CPWC. When the p value is globally fixed to 2 as in conventional DMAS, though the main-lobe width and the image contrast in the experiments improve from 0.57 mm and 27.0 dB in CPWC, respectively, to 0.24 mm and 38.0 dB, the corresponding CNR decreases from 12.8 to 11.3 due to the degraded speckle quality. With the proposed ADMAS algorithm, however, the adaptive p value in DMAS beamforming helps to restore the CNR value to the same level of CPWC while the improvement in image resolution and contrast remains evident.
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exo-6b2-Methyl-substituted pentabenzocorannulene (exo-PBC-Me) was synthesized by the palladium-catalyzed cyclization of 1,2,3-triaryl-1H-cyclopenta[l]phenanthrene. Its bowl-shaped geometry with an sp3 carbon atom in the backbone and a methyl group located at the convex (exo) face was verified by X-ray crystallography. According to DFT calculations, the observed conformer is energetically more favorable than the endo one by 39.9â kcal/mol. Compared to the nitrogen-doped analogs with intact π-conjugated backbones (see the main text), exo-PBC-Me displayed a deeper bowl depth (avg. 1.93â Å), redshifted and broader absorption (250-620â nm) and emission (from 585 to more than 850â nm) bands and a smaller optical HOMO-LUMO gap (2.01â eV). exo-PBC-Me formed polar crystals where all bowl-in-bowl stacking with close π â â â π contacts is arranged unidirectionally, providing the potential for applications as organic semiconductors and pyroelectric materials. This unusual structural feature, molecular packing, and properties are most likely associated with the assistance of the methyl group and the sp3 carbon atom in the backbone.
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PREMISE: Unique among vascular plants, some species of Selaginella have single giant chloroplasts in their epidermal or upper mesophyll cells (monoplastidy, M), varying in structure between species. Structural variants include several forms of bizonoplast with unique dimorphic ultrastructure. Better understanding of these structural variants, their prevalence, environmental correlates and phylogenetic association, has the potential to shed new light on chloroplast biology unavailable from any other plant group. METHODS: The chloroplast ultrastructure of 76 Selaginella species was studied with various microscopic techniques. Environmental data for selected species and subgeneric relationships were compared against chloroplast traits. RESULTS: We delineated five chloroplast categories: ME (monoplastidy in a dorsal epidermal cell), MM (monoplastidy in a mesophyll cell), OL (oligoplastidy), Mu (multiplastidy, present in the most basal species), and RC (reduced or vestigial chloroplasts). Of 44 ME species, 11 have bizonoplasts, cup-shaped (concave upper zone) or bilobed (basal hinge, a new discovery), with upper zones of parallel thylakoid membranes varying subtly between species. Monoplastidy, found in 49 species, is strongly shade associated. Bizonoplasts are only known in deep-shade species (<2.1% full sunlight) of subgenus Stachygynandrum but in both the Old and New Worlds. CONCLUSIONS: Multiplastidic chloroplasts are most likely basal, implying that monoplastidy and bizonoplasts are derived traits, with monoplastidy evolving at least twice, potentially as an adaptation to low light. Although there is insufficient information to understand the adaptive significance of the numerous structural variants, they are unmatched in the vascular plants, suggesting unusual evolutionary flexibility in this ancient plant genus.
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Selaginellaceae , Tracheophyta , Evolución Biológica , Cloroplastos , Filogenia , Hojas de la PlantaRESUMEN
We propose and demonstrate a passively Q-switched 1900-nm thulium all-fiber laser using the mode-field-area mismatch method. A thulium fiber laser was core-pumped at 1590 nm and saturable-absorber Q-switched at 1900 nm through the use of a thulium saturable absorber fiber that had a relatively smaller mode field area than the gain medium. Sequential pulsing with a pulse energy of 12 µJ and a pulse duration of 160 ns was obtained. The pulse repetition rate was increased linearly with the applied pump power. With a pump power of 4.5 W, an average output power of 0.61 W and a pulse repetition rate of 50.7 kHz were achieved.
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PURPOSE: Here we report the development of quantiosomes, niosomes formed from Span 60, cholesterol, and quantum dots (QDs), for achieving sensitive bioimaging and anticancer drug delivery. METHODS: The nanocarriers were further modified by incorporating soy phosphatidylcholine (SPC), polyethylene glycol (PEG), or cationic surfactant to display different efficiencies. Carboplatin was used as the model drug. The cellular uptake, cytotoxicity, and migration inhibition of quantiosomes for treating melanoma cells were described. Finally, intratumoral carboplatin accumulation and in-vivo bioimaging were examined. RESULTS: The average diameters of quantiosomes ranged between 151 and 173 nm, depending on the composition selected. Approximately 50% of the drug was entrapped in quantiosomes. Electron microscopy confirmed the bilayer structure of quantiosomes and the presence of QDs in the vesicular surface. The nanodispersions showed a significant internalization into cells, especially the cationic formulations. Quantiosomes increased cytotoxicity against melanoma by 3 ~ 4-fold as compared to free carboplatin. In-vivo intratumoral administration demonstrated an increased drug depot in melanoma from 6 to 10 ng/mg by SPC-loaded and PEGylated quantiosomes relative to aqueous control. In-vivo fluorescence imaging showed that quantiosomes reduced leakage of QDs from melanoma. A fluorescence signal confined in tumors could be sustained for at least 24 h. Quantiosomes also exhibited a sensitive and prolonged fluorescence in ovarian tumors. CONCLUSION: Niosomes containing QDs and carboplatin as a multifunctional nanosystems provide a non-expensive and efficient strategy to prolong drug retention and fluorescence signal in tumors.
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Antineoplásicos/administración & dosificación , Carboplatino/administración & dosificación , Diagnóstico por Imagen/métodos , Portadores de Fármacos/química , Puntos Cuánticos/química , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Carboplatino/farmacocinética , Carboplatino/farmacología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Colesterol/química , Composición de Medicamentos , Liberación de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Hexosas/química , Liposomas , Melanoma/patología , Ratones Desnudos , Trasplante de Neoplasias , Imagen Óptica/métodos , Neoplasias Ováricas/patología , Tamaño de la Partícula , Propiedades de SuperficieRESUMEN
Wolfberry, also known as goji berry or Lycium barbarum, is a highly valued fruit with significant health benefits and nutritional value. For more efficient and comprehensive usage of published L. barbarum genomic data, we established the Wolfberry database. The utility of the Wolfberry Genome Database (WGDB) is highlighted through the Genome browser, which enables the user to explore the L. barbarum genome, browse specific chromosomes, and access gene sequences. Gene annotation features provide comprehensive information about gene functions, locations, expression profiles, pathway involvement, protein domains, and regulatory transcription factors. The transcriptome feature allows the user to explore gene expression patterns using transcripts per kilobase million (TPM) and fragments per kilobase per million mapped reads (FPKM) metrics. The Metabolism pathway page provides insights into metabolic pathways and the involvement of the selected genes. In addition to the database content, we also introduce six analysis tools developed for the WGDB. These tools offer functionalities for gene function prediction, nucleotide and amino acid BLAST analysis, protein domain analysis, GO annotation, and gene expression pattern analysis. The WGDB is freely accessible at https://cosbi7.ee.ncku.edu.tw/Wolfberry/. Overall, WGDB serves as a valuable resource for researchers interested in the genomics and transcriptomics of L. barbarum. Its user-friendly web interface and comprehensive data facilitate the exploration of gene functions, regulatory mechanisms, and metabolic pathways, ultimately contributing to a deeper understanding of wolfberry and its potential applications in agronomy and nutrition.
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The retrieval of snow grain size is one of the important research directions for cryosphere snow remote sensing. In the present study, we designed the measurement plan of different snow grain size by different snow layer. A SVC HR-1024 ground-based spectral radiometer was used for measuring the spectral property of different snow grain size in northern Xinjiang, China. At the same time, the snow grain size and shape were measured by a hand-loupe with scale. Then the DSPP method was used to calculate the equivalent snow grain size. Finally, the asymptotic radiative transfer (ART) theory was applied to retrieve the snow grain size from measured snow spectral reflectance of different snow layer by optimizing the inversion band and the snow grain size factor "b". The retrieved snow grain size was validated by the measured snow grain size from DSPP method. The results showed that the DSPP method is an effective means of measuring the equivalent snow grain size. However, there is a large deviation of the snow grain size sample in the same snow layer. It is necessary to improve the measurement method of the single snow grain size sample; The study showed that the near-infrared bands are the most effective selection for retrieval of snow grain size. The retrieval algorithm from ART is feasible. When the snow is dry, the authors optimize the inversion band and the snow grain size factor b in the Northern Xinjiang, China. The optimal band wavelength is 1.20 microm and b is 3.62.
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BACKGROUND/AIM: The effect of pelvic neoadjuvant radiotherapy (nRT) for stage M1a rectal adenocarcinoma patients treated with systemic therapy followed by proctectomy and metastasectomy was scarcely investigated in the literatures. PATIENTS AND METHODS: The eligible rectal cancer patients diagnosed between 2011-2019 were identified via the Taiwan Cancer Registry. In the primary analysis, we used propensity score weighting to balance observable potential confounders and compared the hazard ratio (HR) of death for the nRT group vs. without RT group. We also compared the incidence of rectal cancer mortality (IRCM) and performed various supplementary analyses. RESULTS: Our primary analyses included 145 patients. nRT was associated with improved OS (HR=0.51, p=0.01). The numerical trends remained similar for IRCM and in supplementary analyses. CONCLUSION: nRT was associated with improved OS in our study population.
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Adenocarcinoma , Metastasectomía , Proctectomía , Neoplasias del Recto , Humanos , Terapia Neoadyuvante , Estudios Retrospectivos , Resultado del Tratamiento , Neoplasias del Recto/radioterapia , Neoplasias del Recto/cirugía , Adenocarcinoma/cirugía , Adenocarcinoma/patología , Estadificación de NeoplasiasRESUMEN
Density dependence and habitat heterogeneity have been recognized as important driving mechanisms that shape the patterns of seedling survival and promote species coexistence in species-rich forests. In this study, we evaluated the relative importance of density dependence by conspecific, heterospecific, and phylogenetically related neighbors and habitat heterogeneity on seedling survival in the Lienhuachih (LHC) Forest, a subtropical, evergreen forest in central Taiwan. Age-specific effects of different variables were also studied. We monitored the fates of 1,642 newly recruited seedlings of woody plants within a 25-ha Forest Dynamics Plot for 2 years. The effects of conspecific, heterospecific, and phylogenetically related neighbors and habitat heterogeneity on seedling survival were analyzed by generalized linear mixed models. Our results indicated that conspecific negative density dependence (CNDD) had a strong impact on seedling survival, and the effects of CNDD increased with seedling age. Heterospecific positive density dependence (HPDD) and phylogenetic positive density dependence (PPDD) had a significant influence on the survival of seedlings, and stronger HPDD and PPDD effects were detected for older seedlings. Furthermore, seedling survival differed among habitats significantly. Seedling survival was significantly higher in the plateau, high-slope, and low-slope habitats than in the valley. Overall, our results suggested that the effects of CNDD, HPDD, PPDD, and habitat heterogeneity influenced seedling survival simultaneously in the LHC subtropical forest, but their relative importance varied with seedling age. Such findings from our subtropical forest were slightly different from tropical forests, and these contrasting patterns may be attributed to differences in abiotic environments. These findings highlight the importance to incorporate phylogenetic relatedness, seedling age, and habitat heterogeneity when investigating the impacts of density dependence on seedling survival that may contribute to species coexistence in seedling communities.
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The plastid genome of the deep-shade plant Selaginella erythropus, which has highly unusual chloroplasts, was characterized using Illumina pair-end sequencing. This plastome is 140,151 bp in length with a large single-copy region (LSC) of 56,133 bp, a small single-copy region (SSC) of 61,268 bp, and two direct repeats (DRs) of 11,375 bp. The overall GC content is 50.68%, while those of LSC, SSC, and DR are 48.96%, 50.3%, and 55.96%, respectively. The plastome contains 102 genes, including 76 protein-coding, 15 tRNA (12 tRNA species), and 8 rRNA genes (4 rRNA species). The phylogenetic analysis shows that S. erythropus is closely related to S. moellendorffii and S. doederleinii. This result is consistent with the previous phylogenetic relationship inferred from multiple plastid and nuclear loci. However, only S. erythropus has the two-zoned giant chloroplast, the bizonoplast. The plastome provides an excellent reference for understanding the unique chloroplast differentiation in Selaginellaceae.
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Mutated channelopathy could play important roles in the pathogenesis of aldosterone-producing adenoma (APA). In this study, we identified a somatic mutation, KCNJ5 157-159delITE, and reported its immunohistological, pathophysiological and pharmacological characteristics. We conducted patch-clamp experiments on HEK293T cells and experiments on expression of aldosterone synthase (CYP11B2) and aldosterone secretion in HAC15 cells to evaluate electrophysiological and functional properties of this mutated KCNJ5. Immunohistochemistry was conducted to identify expressions of several steroidogenic enzymes. Macrolide antibiotics and a calcium channel blocker were administrated to evaluate the functional attenuation of mutated KCNJ5 channel in transfected HAC15 cells. The interaction between macrolides and KCNJ5 protein was evaluated via molecular docking and molecular dynamics simulation analysis. The immunohistochemistry analysis showed strong CYP11B2 immunoreactivity in the APA harboring KCNJ5 157-159delITE mutation. Whole-cell patch-clamp data revealed that mutated KCNJ5 157-159delITE channel exhibited loss of potassium ion selectivity. The mutant-transfected HAC15 cells increased the expression of CYP11B2 and aldosterone secretion, which was partially suppressed by clarithromycin and nifedipine but not roxithromycin treatment. The docking analysis and molecular dynamics simulation disclosed that roxithromycin had strong interaction with KCNJ5 L168R mutant channel but not with this KCNJ5 157-159delITE mutant channel. We showed comprehensive evaluations of the KCNJ5 157-159delITE mutation which revealed that it disrupted potassium channel selectivity and aggravated autonomous aldosterone production. We further demonstrated that macrolide antibiotics, roxithromycin, could not interfere the aberrant electrophysiological properties and gain-of-function aldosterone secretion induced by KCNJ5 157-159delITE mutation.
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The levels of fibroblast growth factor 23 (FGF23) rapidly increases after acute kidney injury (AKI). However, the role of FGF23 in AKI is still unclear. Here, we observe that pretreatment with FGF23 protein into ischemia-reperfusion induced AKI mice ameliorates kidney injury by promoting renal tubular regeneration, proliferation, vascular repair, and attenuating tubular damage. In vitro assays demonstrate that SDF-1 induces upregulation of its receptor CXCR4 in endothelial progenitor cells (EPCs) via a non-canonical NF-κB signaling pathway. FGF23 crosstalks with the SDF-1/CXCR4 signaling and abrogates SDF-1-induced EPC senescence and migration, but not angiogenesis, in a Klotho-independent manner. The downregulated pro-angiogenic IL-6, IL-8, and VEGF-A expressions after SDF-1 infusion are rescued after adding FGF23. Diminished therapeutic ability of SDF-1-treated EPCs is counteracted by FGF23 in a SCID mouse in vivo AKI model. Together, these data highlight a revolutionary and important role that FGF23 plays in the nephroprotection of IR-AKI.
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Lesión Renal Aguda/metabolismo , Células Progenitoras Endoteliales/metabolismo , Factores de Crecimiento de Fibroblastos/metabolismo , Receptores CXCR4/metabolismo , Lesión Renal Aguda/patología , Animales , Células Progenitoras Endoteliales/patología , Factor-23 de Crecimiento de Fibroblastos , Masculino , Ratones , Ratones SCIDRESUMEN
Current knowledge of the microbial communities within biological wastewater treatment reactors is incomplete due to limitations of traditional culture-based techniques and despite the emergence of recently applied molecular techniques. Here we demonstrate the application of high-density microarrays targeting universal 16S rRNA genes to evaluate microbial community composition in five biological wastewater treatment reactors in China and the United States. Results suggest a surprisingly consistent composition of microbial community structure among all five reactors. All investigated communities contained a core of bacterial phyla (53-82% of 2119 taxa identified) with almost identical compositions (as determined by colinearity analysis). These core species were distributed widely in terms of abundance but their proportions were virtually the same in all samples. Proteobacteria was the largest phylum and Firmicutes, Actinobacteria, Bacteroidetes were the subdominant phyla. The diversity among the samples can be attributed solely to a group of operational taxonomic units (OTUs) that were detected only in specific samples. Typically, these organisms ranked somewhat lower in terms of abundance but a few were present is much higher proportions.
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Bacterias/aislamiento & purificación , Reactores Biológicos , Microbiología del Agua , Bacterias/clasificación , Filogenia , Aguas del Alcantarillado/microbiologíaRESUMEN
OBJECTIVE: To analyze the Chinese medicine syndrome types of patients undergoing maintenance peritoneal dialysis to provide some clinical reference for the treatment based on syndromes. METHODS: According to the criterion made by the Nephropathy Branch of China Association of Chinese Medicine in 2006, the syndrome type of 156 patients were differentiated, and the related laboratory parameters, including serum albumin (ALB), C-reactive protein (CRP), hemoglobin (HB), total urea clearance rate (KT/Vt), residual kidney urea clearance (KT/Vr), blood flow mediated vascular endothelial dilatation (FMD) and volume overload (OH) were measured. RESULTS: Syndrome type presented in patients was different. Along with the progress of dialysis, it changed in the root syndromes from qi-deficiency to yang-deficiency and further to both yin-yang deficiency, while in the superficial syndromes it turned from turbid-damp to blood-stasis. ALB in patients with Pi-shen yang-deficiency type and both yin-yang deficiency type was significantly lower than that in patients with Pi-Shen qi-deficiency type and both qi-yin deficiency type (P < 0.05); KT/Vt in both yin-yang deficiency type was the lowest, significantly lower than that in Gan-Shen yin-deficiency type and both qi-yin deficiency (P < 0.05); OH in Pi-Shen yang-deficiency type and both yin-yang deficiency type was significantly higher than that in other types (P < 0.01). Comparison of patients' age showed that group of patients without superficial syndrome was the youngest and the group of patients with damp-heat syndrome type was the oldest (P < 0.01). CRP in damp-heat type was significantly higher than that in other types (P < 0.05); FMD was lower in blood-stasis type than in turbid-damp type and toxic heat type (P < 0.01); and OH was significantly higher in turbid-damp type than in other types (P < 0.01). CONCLUSION: Some rules of syndrome type distribution could be seen in patients undergoing peritoneal dialysis, which is related with some laboratory parameters to a certain extent, so may provide a few references for clinical treatment based on syndrome type.
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Medicina Tradicional China/métodos , Diálisis Peritoneal Ambulatoria Continua , Adulto , Anciano , Anciano de 80 o más Años , Proteína C-Reactiva/metabolismo , Femenino , Humanos , Inflamación , Masculino , Persona de Mediana Edad , Albúmina Sérica/metabolismoRESUMEN
Rice blast disease resistance to the fungal pathogen Magnaporthe grisea is triggered by a physical interaction between the protein products of the host R (resistance) gene, Pi-ta, and the pathogen Avr (avirulence) gene, AVR-pita. The genotype variation and resistant/susceptible phenotype at the Pi-ta locus of wild rice (Oryza rufipogon), the ancestor of cultivated rice (O. sativa), was surveyed in 36 locations worldwide to study the molecular evolution and functional adaptation of the Pi-ta gene. The low nucleotide polymorphism of the Pi-ta gene of O. rufipogon was similar to that of O. sativa, but greatly differed from what has been reported for other O. rufipogon genes. The haplotypes can be subdivided into two divergent haplogroups named H1 and H2. H1 is derived from H2, with nearly no variation and at a low frequency. H2 is common and is the ancestral form. The leucine-rich repeat (LRR) domain has a high pi(non)/pi(syn) ratio, and the low polymorphism of the Pi-ta gene might have primarily been caused by recurrent selective sweep and constraint by other putative physiological functions. Meanwhile, we provide data to show that the amino acid Ala-918 of H1 in the LRR domain has a close relationship with the resistant phenotype. H1 might have recently arisen during rice domestication and may be associated with the scenario of a blast pathogen-host shift from Italian millet to rice.
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Evolución Molecular , Genes de Plantas , Inmunidad Innata/genética , Oryza/genética , Oryza/inmunología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Secuencia de Bases , ADN de Plantas/genética , Geografía , Inmunidad Innata/inmunología , Funciones de Verosimilitud , Magnaporthe/fisiología , Modelos Genéticos , Datos de Secuencia Molecular , Oryza/microbiología , Fenotipo , Enfermedades de las Plantas/microbiología , Polimorfismo Genético , Selección GenéticaRESUMEN
BACKGROUND: CBF/DREB duplicate genes are widely distributed in higher plants and encode transcriptional factors, or CBFs, which bind a DNA regulatory element and impart responsiveness to low temperatures and dehydration. RESULTS: We explored patterns of genetic variations of CBF1, -2, and -3 from 34 accessions of Arabidopsis thaliana. Molecular population genetic analyses of these genes indicated that CBF2 has much reduced nucleotide diversity in the transcriptional unit and promoter, suggesting that CBF2 has been subjected to a recent adaptive sweep, which agrees with reports of a regulatory protein of CBF2. Investigating the ratios of Ka/Ks between all paired CBF paralogus genes, high conservation of the AP2 domain was observed, and the major divergence of proteins was the result of relaxation in two regions within the transcriptional activation domain which was under positive selection after CBF duplication. With respect to the level of CBF gene expression, several mutated nucleotides in the promoters of CBF3 and -1 of specific ecotypes might be responsible for its consistently low expression. CONCLUSION: We concluded from our data that important evolutionary changes in CBF1, -2, and -3 may have primarily occurred at the level of gene regulation as well as in protein function.
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Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Genes Duplicados/genética , Secuencia de Aminoácidos , Proteínas de Arabidopsis/química , Técnicas de Silenciamiento del Gen , Técnicas de Inactivación de Genes , Genética de Población , Genoma de Planta/genética , Datos de Secuencia Molecular , Filogenia , Polimorfismo Genético , Regiones Promotoras Genéticas , Estructura Terciaria de Proteína , Selección Genética , Análisis de Secuencia de ADN , Transactivadores/química , Transactivadores/genética , Factores de Transcripción/química , Factores de Transcripción/genética , Transcripción Genética , Activación Transcripcional/genéticaRESUMEN
A clone containing a 3903 bp EcoRI-restriction fragment was obtained from a lambda(ZAP) genomic library of loofah witches' broom (LfWB) phytoplasma by plaque hybridization using a PCR fragment as a probe. Sequence analysis revealed that this fragment contained three open reading frames (ORFs). The deduced amino acid sequences of ORF 1 and ORF 2 showed a high homology with the ATP-binding proteins of the ABC transporter system genes of prokaryotes and eukaryotes, and encoded proteins with a molecular mass of 36 and 30 kDa, respectively. Based on amino acid sequence similarity, secondary structure, hydrophilicity and a signal peptide sequence at the N-terminus, we predicted that ORF 3 might encode a specific solute-binding prolipoprotein of the ABC transporter system with a molecular mass of 62 kDa. The cleavage site of this prolipoprotein signal peptide was similar to those of gram-positive bacteria. In addition to nutrient uptake, ABC transporter systems of bacteria also play a role in signal transduction, drug-resistance and perhaps virulence. The possible implications of the system to the survival and the pathogenesis of phytoplasma were discussed.
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Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/aislamiento & purificación , Phytoplasma/genética , Phytoplasma/aislamiento & purificación , Plantas/microbiología , Regiones no Traducidas 3' , Transportadoras de Casetes de Unión a ATP/química , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN Bacteriano/química , Biblioteca Genómica , Interacciones Hidrofóbicas e Hidrofílicas , Datos de Secuencia Molecular , Peso Molecular , Sistemas de Lectura Abierta , Operón , Phytoplasma/clasificación , Señales de Clasificación de Proteína , Estructura Secundaria de Proteína , Análisis de Secuencia de ADN , Homología de Secuencia de AminoácidoRESUMEN
Genetic variation evolves during postglacial range expansion of a species and is important for adapting to varied environmental conditions. It is crucial for the future survival of a species. We investigate the nuclear DNA sequence variation to provide evidence of postglacial range expansion of Musa basjoo var. formosana, a wild banana species, and test for adaptive evolution of amplified fragment length polymorphic (AFLP) loci underlying local adaptation in association with environmental variables. Postglacial range expansion was suggested by phylogeographical analyses based on sequence variation of the second intron of copper zinc superoxide dismutase 2 gene. Two glacial refugia were inferred by the average F ST parameter (mean F ST of a population against the remaining populations). Using variation partitioning by redundancy analysis, we found a significant amount of explained AFLP variation attributed to environmental and spatially-structured environmental effects. By combining genome scan methods and multiple univariate logistic regression, four AFLP loci were found to be strongly associated with environmental variables, including temperature, precipitation, soil moisture, wet days, and surface coverage activity representing vegetation greenness. These environmental variables may have played various roles as ecological drivers for adaptive evolution of M. basjoo var. formosana during range expansion after the last glacial maximum.
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Ecosistema , Musa/crecimiento & desarrollo , Dispersión de las Plantas , Adaptación Biológica , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Clima , ADN de Plantas/genética , Variación Genética , Genética de Población , Musa/clasificación , Musa/genética , FilogeografíaRESUMEN
A fundamental goal in ecology is to link variation in species function to performance, but functional trait-performance investigations have had mixed success. This indicates that less commonly measured functional traits may more clearly elucidate trait-performance relationships. Despite the potential importance of leaf vein traits, which are expected to be related to resource delivery rates and photosynthetic capacity, there are few studies, which examine associations between these traits and demographic performance in communities. Here, we examined the associations between species traits including leaf venation traits and demographic rates (Relative Growth Rate, RGR and mortality) as well as the spatial distributions of traits along soil environment for 54 co-occurring species in a subtropical forest. Size-related changes in demographic rates were estimated using a hierarchical Bayesian approach. Next, Kendall's rank correlations were quantified between traits and estimated demographic rates at a given size and between traits and species-average soil environment. Species with denser venation, smaller areoles, less succulent, or thinner leaves showed higher RGR for a wide range of size classes. Species with leaves of denser veins, larger area, cheaper construction costs or thinner, or low-density wood were associated with high mortality rates only in small size classes. Lastly, contrary to our expectations, acquisitive traits were not related to resource-rich edaphic conditions. This study shows that leaf vein traits are weakly, but significantly related to tree demographic performance together with other species traits. Because leaf traits associated with an acquisitive strategy such as denser venation, less succulence, and thinner leaves showed higher growth rate, but similar leaf traits were not associated with mortality, different pathways may shape species growth and survival. This study suggests that we are still not measuring some of key traits related to resource-use strategies, which dictate the demography and distributions of species.
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BACKGROUND/AIM: Capecitabine is the current standard oral chemotherapy used in neoadjuvant concurrent chemoradiotherapy (NCCRT) for locally advanced rectal cancer (LARC) in North America. We compared the effectiveness of another oral chemotherapy agent, UFT (an oral combination of uracil and tegafur), to that of capecitabine. MATERIALS AND METHODS: We identified LARC patients diagnosed from 2007 to 2011 using a population-based registry in Taiwan (Health and Welfare Data Science Center, HWDC) and constructed a propensity score matched cohort to balance observable potential confounders. We compared the hazard ratio (HR) of death between the UFT and capecitabine groups. We performed supplementary analysis (SA) to evaluate the robustness of our finding regarding potential unobserved confounders (SA-1) and the robustness of the result in a subgroup when an additional potential confounder was taken into account (SA-2). RESULTS: Our study population comprised of 200 patients balanced with respect to observed co-variables. UFT lowered the hazard of death significantly more than capecitabine (HR=0.58, 95% confidence interval (CI)=0.35-0.95, p=0.03). Our result was moderately sensitive in SA-1 but not significant in SA-2. CONCLUSION: The effectiveness of UFT in NCCRT for LARC is probably non-inferior to that of capecitabine.