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1.
BMC Neurol ; 24(1): 246, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39014305

RESUMEN

BACKGROUND: To investigate the association between white matter changes and ventricular expansion in idiopathic normal pressure hydrocephalus (iNPH) based on diffusion spectrum imaging (DSI). METHODS: We included 32 patients with iNPH who underwent DSI using a 3T MRI scanner. The lateral ventricles were manually segmented, and ventricular volumes were measured. Two methods were utilised in the study: manual region-of-interest (ROI) delineation and tract diffusion profile analysis. General fractional anisotropy (GFA) and fractional anisotropy (FA) were extracted in different white matter regions, including the bilateral internal capsule (anterior and posterior limbs) and corpus callosum (body, genu, and splenium) with manual ROI delineation. The 18 main tracts in the brain of each patient were extracted; the diffusion metrics of 100 equidistant nodes on each fibre were calculated, and Spearman's correlation coefficient was used to determine the correlation between diffusion measures and ventricular volume of iNPH patients. RESULTS: The GFA and FA of all ROI showed no significant correlation with lateral ventricular volume. However, in the tract diffusion profile analysis, lateral ventricular volume was positively correlated with part of the cingulum bundle, left corticospinal tract, and bilateral thalamic radiation posterior, whereas it was negatively correlated with the bilateral cingulum parahippocampal (all p < 0.05). CONCLUSIONS: The effect of ventricular enlargement in iNPH on some white matter fibre tracts around the ventricles was limited and polarizing, and most white matter fibre tract integrity changes were not associated with ventricular enlargement; this reflects that multiple pathological mechanisms may have been combined to cause white matter alterations in iNPH.


Asunto(s)
Hidrocéfalo Normotenso , Sustancia Blanca , Humanos , Hidrocéfalo Normotenso/diagnóstico por imagen , Hidrocéfalo Normotenso/patología , Masculino , Femenino , Anciano , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Anciano de 80 o más Años , Imagen de Difusión Tensora/métodos , Persona de Mediana Edad , Imagen de Difusión por Resonancia Magnética/métodos , Ventrículos Cerebrales/diagnóstico por imagen , Ventrículos Cerebrales/patología , Anisotropía
2.
Eur Radiol ; 32(11): 7800-7810, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35501572

RESUMEN

OBJECTIVES: To explore the value of structural neuroimaging in predicting the prognosis of shunt surgery for idiopathic normal-pressure hydrocephalus (iNPH) using two different standard semi-quantitative imaging scales. METHODS: A total of 47 patients with iNPH who underwent shunt surgery at our hospital between 2018 and 2020 were included in this study. The modified Rankin Scale (mRS) and iNPH grading scale (iNPHGS) were used to evaluate and quantify the clinical symptoms before and after shunt surgery. The disproportionately enlarged subarachnoid space hydrocephalus (DESH) and iNPH Radscale scores were used to evaluate the preoperative MR images. The primary endpoint was improvement in the mRS score a year after surgery, and the secondary endpoint was the iNPHGS after 1 year. The preoperative imaging features of the improved and non-improved groups were compared. RESULTS: The rates of the primary and secondary outcomes were 59.6% and 61.7%, respectively, 1 year after surgery. There were no significant differences in preoperative DESH score, iNPH Radscale, Evans' index (EI), or callosal angle (CA) between the improved and non-improved groups. Significant correlations were observed between the severity of gait disorder and EI and the CA. CONCLUSIONS: The value of structural neuroimaging in predicting the prognosis of shunt surgery is limited, and screening for shunt surgery candidates should not rely only on preoperative imaging findings. KEY POINTS: • Early shunt surgery can significantly improve the clinical symptoms and prognosis of patients with idiopathic normal-pressure hydrocephalus (iNPH). • Structural imaging findings have limited predictiveness for the prognosis of patients with iNPH after shunt surgery. • Patients should not be selected for shunt surgery based on only structural imaging findings.


Asunto(s)
Fístula , Hidrocéfalo Normotenso , Humanos , Hidrocéfalo Normotenso/diagnóstico por imagen , Hidrocéfalo Normotenso/cirugía , Neuroimagen , Imagen por Resonancia Magnética , Pronóstico , Cuerpo Calloso
3.
Am J Bot ; 106(1): 42-50, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30629301

RESUMEN

PREMISE OF THE STUDY: Sex-specific differences in reproductive investment contribute to sexual dimorphism in dioecious plants. Along environmental gradients, males and females may plastically adjust reproductive allocation differently because of contrasting reproductive costs. In dioecious macrophytes, variation in water depth is likely to influence reproductive allocation but has not been investigated in detail. METHODS: Vallisneria spinulosa was grown in aquatic mesocosms at water depths of 50, 100 and 150 cm for 14 weeks. Plasticity in allocation was measured to investigate whether sexual dimorphism in reproductive allocation and vegetative growth changed in response to varying water depths. KEY RESULTS: Females invested a higher fraction of resources to sexual reproduction than males across all water depths and decreased proportional allocation to sexual structures in shallow and deep water compared to intermediate water depth. In contrast, males maintained similar sexual allocation across all water depths. Females displayed larger vegetative size than males, despite greater sexual investment, but decreased vegetative biomass more than males in shallow or deep water. The sexes invested similarly in clonal propagation by tubers at all water depths, but a trade-off with sexual reproduction was only evident in females. CONCLUSIONS: Our results suggest that females of V. spinulosa have mechanisms to compensate for the costs of sexual reproduction in heterogeneous environments. Compared to males, females expressed greater plasticity in biomass allocated to sexual reproduction and vegetative growth in response to water depth variation. Environmental variation in underwater light availability probably caused the sex-specific allocation strategies found in V. spinulosa.


Asunto(s)
Flores/crecimiento & desarrollo , Hydrocharitaceae/crecimiento & desarrollo , Adaptación Fisiológica , Luz , Reproducción , Caracteres Sexuales
4.
BMC Genomics ; 18(1): 211, 2017 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-28241790

RESUMEN

BACKGROUND: Cold tolerance is a key determinant of the geographical distribution range of a plant species and crop production. Cold acclimation can enhance freezing-tolerance of plant species through a period of exposure to low nonfreezing temperatures. As a subtropical evergreen broadleaf plant, oil-tea camellia demonstrates a relatively strong tolerance to freezing temperatures. Moreover, wild oil-tea camellia is an essential genetic resource for the breeding of cultivated oil-tea camellia, one of the four major woody oil crops in the world. The aims of our study are to identify variations in transcriptomes of wild oil-tea camellia from different latitudes and elevations, and discover candidate genes for cold acclimation. RESULTS: Leaf transcriptomes were obtained of wild oil-tea camellia from different elevations in Lu and Jinggang Mountains, China. Huge amounts of simple sequence repeats (SSRs), single-nucleotide polymorphisms (SNPs) and insertion/deletions (InDels) were identified. Based on SNPs, phylogenetic analysis was performed to detect genetic structure. Wild oil-tea camellia samples were genetically differentiated mainly between latitudes (between Lu and Jinggang Mountains) and then among elevations (within Lu or Jinggang Mountain). Gene expression patterns of wild oil-tea camellia samples were compared among different air temperatures, and differentially expressed genes (DEGs) were discovered. When air temperatures were below 10 °C, gene expression patterns changed dramatically and majority of the DEGs were up-regulated at low temperatures. More DEGs concerned with cold acclimation were detected at 2 °C than at 5 °C, and a putative C-repeat binding factor (CBF) gene was significantly up-regulated only at 2 °C, suggesting a stronger cold stress at 2 °C. We developed a new method for identifying significant functional groups of DEGs. Among the DEGs, transmembrane transporter genes were found to be predominant and many of them encoded transmembrane sugar transporters. CONCLUSIONS: Our study provides one of the largest transcriptome dataset in the genus Camellia. Wild oil-tea camellia populations were genetically differentiated between latitudes. It may undergo cold acclimation when air temperatures are below 10 °C. Candidate genes for cold acclimation may be predominantly involved in transmembrane transporter activities.


Asunto(s)
Aclimatación/genética , Camellia/genética , Camellia/fisiología , Frío , Perfilación de la Expresión Génica , Hojas de la Planta/genética , Mutación INDEL , Repeticiones de Microsatélite/genética , Anotación de Secuencia Molecular , Polimorfismo de Nucleótido Simple
5.
Biol Pharm Bull ; 40(5): 583-593, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-28190857

RESUMEN

Tyrosol (Tyr) is a natural antioxidant that displays anti-oxidant and anti-inflammatory properties. The present study aimed to investigate the effect and mechanism of Tyr on lipopolysaccharide (LPS)-induced acute lung injury (ALI). In a mouse model, we found that pretreatment with Tyr significantly improved survival rate, attenuated lung permeability, ameliorated histopathological alterations, reduced expression of the inflammatory mediators and improved expression of the antioxidant enzyme. Further study revealed that Tyr markedly inhibited nuclear factor-κB (NF-κB) and activator protein-1 (AP-1) activation at both in vivo and in vitro levels. To investigate the underlying mechanism, we examined the impact of Tyr on the heme oxygenase (HO)-1/nuclear factor erythroid-2 related factor 2 (Nrf2) pathway in vivo and in vitro. The results showed that Tyr significantly improved the expression of HO-1 and the activation of Nrf2. This study offers novel evidence to support the efficacy of Tyr against ALI, which helps to clarify the underlying causes of the therapeutic effects behind Tyr.


Asunto(s)
Lesión Pulmonar Aguda/prevención & control , Hemo-Oxigenasa 1/fisiología , Lipopolisacáridos/farmacología , Factor 2 Relacionado con NF-E2/fisiología , FN-kappa B/antagonistas & inhibidores , Alcohol Feniletílico/análogos & derivados , Transducción de Señal/efectos de los fármacos , Factor de Transcripción AP-1/antagonistas & inhibidores , Animales , Células Cultivadas , Masculino , Ratones , Ratones Endogámicos C57BL , Peroxidasa/metabolismo , Alcohol Feniletílico/farmacología , Transducción de Señal/fisiología
6.
Biochem Biophys Res Commun ; 478(2): 649-55, 2016 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-27495872

RESUMEN

Lung cancer remains a leading cause of cancer-associated mortality worldwide and non-small lung cancer (NSCLC) is responsible for over 80% of lung cancer-related deaths. Identifying novel molecular biomarker that can inhibit the progression of lung cancer will facilitate the development of new treatment strategies. Herein, we demonstrated that miR-187-5p is a tumor-suppressor miRNA in NSCLC progression. We found that expression of miR-187-5p was decreased obviously in NSCLC tissues. Down-regulation of miR-187-5p was associated with TNM stage and postoperative survival. Overexpression of miR-187-5p inhibited the growth and metastasis of NSCLC cells. The CYP1B1 was a direct target of miR-187-5p and promoted the growth and metastasis of NSCLC cells. Further study showed that CYP1B1 could reverse the inhibitory effect of miR-187-5p on growth and metastasis of NSCLC cells. Taken together, our data highlight the pivotal role of miR-187-5p in the progression of NSCLC. Thus, miR-187-5p may be a potential prognostic marker and of treatment relevance for NSCLC progression intervention.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Citocromo P-450 CYP1B1/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/genética , MicroARNs/genética , Anciano , Secuencia de Bases , Biomarcadores de Tumor/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Citocromo P-450 CYP1B1/metabolismo , Progresión de la Enfermedad , Femenino , Genes Reporteros , Humanos , Luciferasas/genética , Luciferasas/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , MicroARNs/metabolismo , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Transducción de Señal , Análisis de Supervivencia
7.
Biochem Biophys Res Commun ; 471(4): 515-21, 2016 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-26891867

RESUMEN

Local inflammatory responses and alveolar epithelial cells (AECs) apoptosis are both important for the development of the acute lung injury (ALI), a clinically important complication causing high morbidity and mortality, but little is known about the molecular mechanisms underlying the pathogenesis. Herein, we showed for the first time that expression of Metastasis-associated protein 1 (MTA1), a master transcriptional regulator with the ability to regulate divergent cellular pathways by modifying the acetylation status of crucial target genes, was up-regulated in the alveolar cells of the Escherichia coli lipopolysaccharide (LPS)-induced murine ALI model. Inhibition of MTA1 expression by in vivo siRNA treatment exacerbated the pathology of LPS-induced ALI, by selectively promoting the expression of NF-κB-regulated inflammatory cytokines. Moreover, ablation of MTA1 expression promoted the LPS-induced apoptosis in AEC II cells, leaving AEC I cells unaffected. These data collectively underscore an alveolar facet of this important chromatin modifier, which may represent as a novel regulator and a new therapeutic target for the treatment of ALI.


Asunto(s)
Lesión Pulmonar Aguda/inmunología , Lesión Pulmonar Aguda/patología , Factores de Transcripción/metabolismo , Animales , Apoptosis , Cromatina/metabolismo , Citocinas/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Escherichia coli , Femenino , Técnicas de Silenciamiento del Gen , Lipopolisacáridos , Ratones , Ratones Endogámicos C57BL , ARN Interferente Pequeño/genética , Proteínas Represoras , Transactivadores , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/genética
8.
BMC Genomics ; 16 Suppl 7: S15, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26099797

RESUMEN

BACKGROUND: Astragalus membranaceus Bge. var. mongolicus (Bge.) Hsiao (A. mongolicus, family Leguminosae) is one of the most important traditional Chinese herbs. Among many secondary metabolites it produces, the effective bioactive constituents include isoflavonoids and triterpene saponins. The genomic resources regarding the biosynthesis of these metabolites in A. mongolicus are limited. Although roots are the primary material harvested for medical use, the biosynthesis of the bioactive compounds and its regulation in A. mongolicus are not well understood. Therefore, a global transcriptome analysis on A. mongolicus tissues was performed to identify the genes essential for the metabolism and to profile their expression patterns in greater details. RESULTS: RNA-sequencing was performed for three different A. mongolicus tissues: leaf, stem, and root, using the Illumina Hiseq2000 platform. A total of 159.5 million raw sequence reads were generated, and assembled into 186,324 unigenes with an N50 of 1,524bp. Among them, 129,966 unigenes (~69.7%) were annotated using four public databases (Swiss-Prot, TrEMBL, CDD, Pfam), and 90,202, 63,946, and 78,326 unigenes were found to express in leaves, roots, and stems, respectively. A total of 8,025 transcription factors (TFs) were identified, in which the four largest families, bHLH, MYB, C3H, and WRKY, were implicated in regulation of tissue development, metabolisms, stress response, etc. Unigenes associated with secondary metabolism, especially those with isolavonoids and triterpene saponins biosynthesis were characterized and profiled. Most genes involved in the isoflavonoids biosynthesis had the lowest expression in the leaves, and the highest in the stems. For triterpene saponin biosynthesis, we found the genes in MVA and non-MVA pathways were differentially expressed among three examined tissues, indicating the parallel but compartmentally separated biosynthesis pathways of IPP and DMAPP in A. mongolicus. The first committed enzyme in triterpene saponin biosynthesis from A. mongolicus, cycloartenol synthase (AmCAS), which belongs to the oxidosqualene cyclase family, was cloned by us to study the astragalosides biosynthesis. Further co-expression analysis indicated the candidate CYP450s and glycosyltransferases (GTs) in the cascade of triterpene saponins biosynthesis. The presence of the large CYP450 families in A. mongolicus was further compared with those from Medicago truncatula and Arabidopsis thaliana, and the diversity and phylegenetic relationships of the CYP450 families were established. CONCLUSION: A transcriptome study was performed for A. mongolicus tissues to construct and profile their metabolic pathways, especially for the important bioactive molecules. The results revealed a comprehensive profile for metabolic activities among tissues, pointing to the equal importance of leaf, stem, and root in A. mongolicus for the production of bioactive compounds. This work provides valuable resources for bioengineering and in vitro synthesis of the natural compounds for medical research and for potential drug development.


Asunto(s)
Astragalus propinquus/genética , Perfilación de la Expresión Génica/métodos , Proteínas de Plantas/genética , Análisis de Secuencia de ARN/métodos , Astragalus propinquus/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Regulación de la Expresión Génica de las Plantas , Variación Genética , Isoflavonas/biosíntesis , Redes y Vías Metabólicas , Filogenia , Proteínas de Plantas/metabolismo , Saponinas/biosíntesis
9.
Mol Phylogenet Evol ; 89: 63-72, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25871774

RESUMEN

Ribosomal DNA (rDNA) repeats often exhibit a high level of within-species homogeneity, but intra-individual polymorphism of rDNA has been found in Camellia species. In order to reveal the evolutionary pattern of rDNA repeats in tea [Camellia sinensis (L.) O. Kuntze], we identified the 45S rDNA loci, estimated their copy number, and cloned partial regions of them from different PCR products and from digested genomic DNA. The results show that there are 3 loci (6 sites) containing 45S rDNA in the tea genome; they are located at the ends of the short arms of 6 chromosomes and consist of a maximum of ∼6500 repeat units. On one hand, 164 sequences of the 26S rDNA cloned from PCR products contained 147 haplotypes, consisting of 62% pseudogenes, 24% putative functional genes, and 14% PCR-mediated recombinants, suggesting that the 45S rDNA of tea maintains an extremely high level of polymorphism and divergence; on the other hand, rDNA fragments cloned directly from genomic DNA exhibited a very high level of homogeneity: only one of 33 rDNA fragments was from a pseudogene. These results demonstrate that although over 60% of the 26S rDNA sequences identified in PCR products belong to pseudogenes, most 45S rDNA repeats are functional genes and have undergone concerted evolution. In this study, strong PCR bias and PCR-mediated recombination greatly increased the apparent proportion of pseudogenes in PCR products. Phylogenetic analysis and genetic divergence values for 26S rDNA sequences obtained in this study show that many pseudogenes have originated independently from functional genes at different times, and despite thus escaping from concerted evolution, they have failed to be eliminated from the tea genome over a long period, some of them having even produced addition copies by rapid expansion. Importantly, our study suggests that in order to determine the true pattern of evolution of rDNA it is necessary to combine data from more than one method rather than relying only on sequences from PCR products.


Asunto(s)
Camellia sinensis/genética , ADN Ribosómico/genética , Evolución Molecular , Polimorfismo Genético/genética , Puntos de Rotura del Cromosoma , Genoma de Planta/genética , Haplotipos/genética , Filogenia , Reacción en Cadena de la Polimerasa , Seudogenes/genética , Recombinación Genética/genética , Té/genética
10.
Protein Expr Purif ; 107: 83-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25462811

RESUMEN

Plant cytochrome P450 enzymes play vital roles in the biosynthesis of plant secondary metabolites, including phenylpropanoids and phytoalexins. Isoflavone-2'-hydroxylase (AmI2'H) from Astragalus membranaceus Bge. Var. mongolicus (Bge.) Hsiao is a membrane protein and an eukaryotic cytochrome P450 enzyme involved in isoflavonoid biosynthesis. We cloned the AmI2'H gene by employing RACE methods and modified the gene sequence to facilitate protein expression and increase protein solubility. Two vectors, pET-28a(+) and pCW ori(+), were used to express AmI2'H in Escherichia coli. The expression efficiency and purity of target protein were analyzed and demonstrated that pET-28a(+) vector containing the AmI2'H gene could produce larger amounts of target proteins with higher purity than pCWori(+). The purified proteins were identified as AmI2'H by LC-ESI-MS/MS analysis and their proper folding was assessed by CO difference spectrum.


Asunto(s)
Astragalus propinquus/enzimología , Clonación Molecular , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/aislamiento & purificación , Proteínas de Plantas/genética , Proteínas de Plantas/aislamiento & purificación , Secuencia de Aminoácidos , Astragalus propinquus/química , Astragalus propinquus/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Datos de Secuencia Molecular , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alineación de Secuencia
11.
PeerJ ; 12: e17545, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38938612

RESUMEN

Background: Patients with lung adenocarcinoma (LUAD) often develop a poor prognosis. Currently, researches on prognostic and immunotherapeutic capacity of aneuploidy-related genes in LUAD are limited. Methods: Genes related to aneuploidy were screened based on bulk RNA sequencing data from public databases using Spearman method. Next, univariate Cox and Lasso regression analyses were performed to establish an aneuploidy-related riskscore (ARS) model. Results derived from bioinformatics analysis were further validated using cellular experiments. In addition, typical LUAD cells were identified by subtype clustering, followed by SCENIC and intercellular communication analyses. Finally, ESTIMATE, ssGSEA and CIBERSORT algorithms were employed to analyze the potential relationship between ARS and tumor immune environment. Results: A five-gene ARS signature was developed. These genes were abnormally high-expressed in LUAD cell lines, and in particular the high expression of CKS1B promoted the proliferative, migratory and invasive phenotypes of LUAD cell lines. Low ARS group had longer overall survival time, higher degrees of inflammatory infiltration, and could benefit more from receiving immunotherapy. Patients in low ASR group responded more actively to traditional chemotherapy drugs (Erlotinib and Roscovitine). The scRNA-seq analysis annotated 17 cell subpopulations into seven cell clusters. Core transcription factors (TFs) such as CREB3L1 and CEBPD were enriched in high ARS cell group, while TFs such as BCLAF1 and UQCRB were enriched in low ARS cell group. CellChat analysis revealed that high ARS cell groups communicated with immune cells via SPP1 (ITGA4-ITGB1) and MK (MDK-NCl) signaling pathways. Conclusion: In this research, integrative analysis based on the ARS model provided a potential direction for improving the diagnosis and treatment of LUAD.


Asunto(s)
Adenocarcinoma del Pulmón , Aneuploidia , Neoplasias Pulmonares , Análisis de la Célula Individual , Humanos , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/patología , Adenocarcinoma del Pulmón/mortalidad , Adenocarcinoma del Pulmón/inmunología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/mortalidad , Pronóstico , Análisis de la Célula Individual/métodos , Quinasas CDC2-CDC28/genética , Quinasas CDC2-CDC28/metabolismo , Línea Celular Tumoral , Análisis de Secuencia de ARN/métodos , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología , Regulación Neoplásica de la Expresión Génica , Biología Computacional/métodos , Masculino
12.
Comput Biol Med ; 180: 108990, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39126788

RESUMEN

Segmentation in medical images is inherently ambiguous. It is crucial to capture the uncertainty in lesion segmentations to assist cancer diagnosis and further interventions. Recent works have made great progress in generating multiple plausible segmentation results as diversified references to account for the uncertainty in lesion segmentations. However, the efficiency of existing models is limited, and the uncertainty information lying in multi-annotated datasets remains to be fully utilized. In this study, we propose a series of methods to corporately deal with the above limitation and leverage the abundant information in multi-annotated datasets: (1) Customized T-time Inner Sampling Network to promote the modeling flexibility and efficiently generate samples matching the ground-truth distribution of a number of annotators; (2) Uncertainty Degree defined for quantitatively measuring the uncertainty of each sample and the imbalance of the whole multi-annotated dataset from a brand new perspective; (3) Uncertainty-aware Data Augmentation Strategy to help probabilistic models adaptively fit samples with different ranges of uncertainty. We have evaluated each of them on both the publicly available lung nodule dataset and our in-house Liver Tumor dataset. Results show that our proposed methods achieves the overall best performance on both accuracy and efficiency, demonstrating its great potential in lesion segmentations and more downstream tasks in real clinical scenarios.

13.
Mol Ecol ; 22(22): 5531-47, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24581006

RESUMEN

Habitat fragmentation weakens the connection between populations and is accompanied with isolation by distance (IBD) and local adaptation (isolation by adaptation, IBA), both leading to genetic divergence between populations. To understand the evolutionary potential of a population and to formulate proper conservation strategies, information on the roles of IBD and IBA in driving population divergence is critical. The putative ancestor of Asian cultivated rice (Oryza sativa) is endangered in China due to habitat loss and fragmentation. We investigated the genetic variation in 11 Chinese Oryza rufipogon populations using 79 microsatellite loci to infer the effects of habitat fragmentation, IBD and IBA on genetic structure. Historical and current gene flows were found to be rare (mh  = 0.0002-0.0013, mc  = 0.007-0.029), indicating IBD and resulting in a high level of population divergence (FST  = 0.343). High within-population genetic variation (HE  = 0.377-0.515), relatively large effective population sizes (Ne  = 96-158), absence of bottlenecks and limited gene flow were found, demonstrating little impact of recent habitat fragmentation on these populations. Eleven gene-linked microsatellite loci were identified as outliers, indicating local adaptation. Hierarchical AMOVA and partial Mantel tests indicated that population divergence of Chinese O. rufipogon was significantly correlated with environmental factors, especially habitat temperature. Common garden trials detected a significant adaptive population divergence associated with latitude. Collectively, these findings imply that IBD due to historical rather than recent fragmentation, followed by local adaptation, has driven population divergence in O. rufipogon.


Asunto(s)
Ecosistema , Evolución Molecular , Variación Genética , Genética de Población , Oryza/genética , Adaptación Fisiológica/genética , China , ADN de Plantas/genética , Flujo Génico , Repeticiones de Microsatélite , Modelos Genéticos , Fenotipo , Densidad de Población , Análisis de Componente Principal , Selección Genética
14.
Ecology ; 94(3): 726-38, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23687898

RESUMEN

Global warming potentially alters the terrestrial carbon (C) cycle, likely feeding back to further climate warming. However, how the ecosystem C cycle responds and feeds back to warming remains unclear. Here we used a meta-analysis approach to quantify the response ratios of 18 variables of the ecosystem C cycle to experimental warming and evaluated ecosystem C-cycle feedback to climate warming. Our results showed that warming stimulated gross ecosystem photosynthesis (GEP) by 15.7%, net primary production (NPP) by 4.4%, and plant C pools from above- and belowground parts by 6.8% and 7.0%, respectively. Experimental warming accelerated litter mass loss by 6.8%, soil respiration by 9.0%, and dissolved organic C leaching by 12.1%. In addition, the responses of some of those variables to experimental warming differed among the ecosystem types. Our results demonstrated that the stimulation of plant-derived C influx basically offset the increase in warming-induced efflux and resulted in insignificant changes in litter and soil C content, indicating that climate warming may not trigger strong positive C-climate feedback from terrestrial ecosystems. Moreover, the increase in plant C storage together with the slight but not statistically significant decrease of net ecosystem exchange (NEE) across ecosystems suggests that terrestrial ecosystems might be a weak C sink rather than a C source under global climate warming. Our results are also potentially useful for parameterizing and benchmarking land surface models in terms of C cycle responses to climate warming.


Asunto(s)
Ciclo del Carbono , Ecosistema , Bacterias/crecimiento & desarrollo , Bacterias/metabolismo , Biomasa , Cambio Climático , Monitoreo del Ambiente , Fotosíntesis , Componentes Aéreos de las Plantas/crecimiento & desarrollo , Raíces de Plantas/crecimiento & desarrollo , Suelo/química
15.
Appl Microbiol Biotechnol ; 97(5): 2219-30, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22539023

RESUMEN

Bacteria and fungi are ecologically important contributors to various functioning of forest ecosystems. In this study, we examined simultaneously the bacterial and fungal distributions in response to elevation changes of a forest. By using clone library analysis from genomic DNA extracted from forest humic clay soils, the composition and diversity of bacterial and fungal communities were determined across an elevation gradient from low via medium to high, in a subtropical forest in the Mountain Lushan, China. Our results showed that soil water content and nutrient availability, specifically total carbon, differed significantly with elevation changes. Although the soil acidity did not differ significantly among the three sites, low pH (around 4) could be an important selection factor selecting for acidophilic Acidobacteria and Alphaproteobacteria, which were the most abundant bacterial clones. As the majority of the fungi recovered, both Basidiomycota and Ascomycota, and their relative abundance were most closely associated with the total carbon. Based on the Shannon-Weaver diversity index and ∫-libshuff analysis, the soil at medium elevation contained the highest diversity of bacteria compared with those at high and low elevations. However, it is difficult to predict overall fungal diversity along elevation. The extreme high soil moisture content which may lead to the formation of anaerobic microhabitats in the forest soils potentially reduces the overall bacterial and fungal diversity.


Asunto(s)
Bacterias/clasificación , Bacterias/aislamiento & purificación , Biota , Hongos/clasificación , Hongos/aislamiento & purificación , Microbiología del Suelo , Altitud , China , ADN Bacteriano/química , ADN Bacteriano/genética , ADN de Hongos/química , ADN de Hongos/genética , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Árboles
16.
Aging (Albany NY) ; 15(12): 5339-5354, 2023 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-37335089

RESUMEN

Lung adenocarcinoma (LUAD) is the most common type of non-small cell lung cancer and accounts for approximately 40% of all lung cancer cases. Multiple distant metastases are the major cause of mortality in lung cancer. In this study, single-cell sequencing datasets of LUAD were utilized to depict the transcriptome characteristic of LUAD based on the bioinformatic method. Firstly, the transcriptome landscape of heterogeneous cell types in LUAD was analyzed and memory T cells, NK cells, and helper T cells were revealed to be the common immune cells in tumor, normal, and metastasis tissue, respectively. Then, marker genes were calculated and 709 genes were identified to play a vital role in the microenvironment of LUAD. While macrophages were reported to act as one of the cells in LUAD, enrichment analysis of macrophage marker genes revealed the important role of macrophages in the activation of neutrophils. Next, the results of cell-cell communication analysis suggested that pericytes interact with broad immune cells via MDK-NCL pathways in metastasis samples, MIF-(CD74+CXCR4) and MIF-(CD74+CC44) interaction especially occurred between different cell types in tumor and normal samples. Finally, bulk RNA-seq was integrated to validate the prognosis effect of the marker gene and the maker gene of M2 macrophage, CCL20, showed the most related to LUAD prognosis. Besides, ZNF90 (Helper T cells), FKBP4 (memory T, helper T, Cytotoxic T, and B cells), CD79A (B cells), TPI1 (pericyte), and HOPX (epithelial cells, pericytes) were also pivotal in the pathology of LUAD, helping researchers understand the molecular insight of microenvironment in LUAD.


Asunto(s)
Adenocarcinoma del Pulmón , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/genética , Pericitos , Análisis de Secuencia de ARN , Microambiente Tumoral/genética , Pronóstico , Biomarcadores de Tumor
17.
Dis Markers ; 2023: 5899662, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36644609

RESUMEN

Background: Currently, how to successfully control refractory and metastatic diseases remains a fundamental goal for clinicians to improve therapeutic effects for patients with non-small cell lung cancer (NSCLC). Several studies have discovered that TRIM58, a member of tripartite motif protein family, shows antitumor effect in multiple types of cancer. In this study, we aimed to further clarify the molecular regulatory network of TRIM58 and corresponding targets for NSCLC patients. Methods: TRIM58 expression in clinical tumor tissue samples and cancer cell lines was examined. Functional experiments including cellular invasion, cell metastasis, chemoresistance assay, and ubiquitination evaluation experiments were conducted to investigate the interaction between TRIM58 and ZEB1, which is a prime element of transcription factor network that controls epithelial-to-mesenchymal transition. Results: TRIM58 expression was characteristically decreased in NSCLC tumor tissues and cancer cell lines. Functional experiments demonstrated that TRIM58 suppression enhanced malignant biological behaviors including cellular survivability, migration, and invasion, as well as stem-like cellular phenotype of tumor cells. TRIM58 silencing also significantly enhanced the chemoresistance of NSCLC cells to chemoagents. TRIM58-ZEB1 interaction accelerated degradation of ZEB1 protein, thus further leading to the augment of tumor behaviors. Further detailed molecular experiments revealed that the interaction between TRIM58 and ZEB1 was mediated via ubiquitin-proteasome pathway (UPP). Conclusion: TRIM58 suppressed NSCLC through interacting with ZEB1 and promoting ZEB1 protein degradation via UPP. The present research sheds light on the interaction between TRIM58 and ZEB1, and TRIM58/ZEB1 axis might be the potential therapeutic targets of NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Proteínas de Motivos Tripartitos , Homeobox 1 de Unión a la E-Box con Dedos de Zinc , Humanos , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Transición Epitelial-Mesenquimal , Neoplasias Pulmonares/patología , Proteolisis , Ubiquitinación , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/genética , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/metabolismo , Proteínas de Motivos Tripartitos/genética , Proteínas de Motivos Tripartitos/metabolismo , Complejo de la Endopetidasa Proteasomal , Ubiquitina
18.
Medicine (Baltimore) ; 102(9): e33157, 2023 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-36862884

RESUMEN

This study was designed to observe the efficacy and safety of albumin-bound paclitaxel plus nedaplatin as neoadjuvant therapy in patients with esophageal squamous cell carcinoma (ESCC). From April 2019 to Dec 2020, patients with ESCC who underwent Mckeown surgery at our center were analyzed retrospectively. All patient received 2 to 3 cycles of albumin-bound paclitaxel combined with nedaplatin before surgery, tumor regression grade (TRG) and American National Cancer Institute Common Toxicity Criteria version 5.0 were used to evaluate its efficacy and safety. TRG grades from TRG 2 to TRG 5are considered effective in chemotherapy, TRG 1 stands for pathological complete response (pCR). A total of 41 patients were included in this study. All patients achieved R0 resection. According to the TRG classification, the number of patients assessed for TRG 1-TRG 5 were: 7 cases, 12 cases, 3 case, 12 cases and 7 cases. Its objective response rate and pCR were 82.9% (34/41) and 17.1% (7/41), respectively. We found that hematological toxicity is the most common adverse events of this regimen, with an incidence of 24.4%, followed by digestive tract reactions, with an incidence of 17.1%. Hair loss, neurotoxicity and hepatological disorder are the others, their incidence was 12.2%, 7.3%, and 2.4%; and chemotherapy related deaths were no found. Notably, 7 patients achieved pCR without recurrence or death. Survival analysis showed that patients with pCR may have longer disease-free survival (P = .085) and overall survival (P = .273), although the difference was not statistically significant. As neoadjuvant therapy for patients with ESCC, albumin-bound paclitaxel combined with nedaplatin has a higher pCR rate and less side effects. It is a reliable choice for ESCC patients as neoadjuvant therapy.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Paclitaxel Unido a Albúmina/uso terapéutico , Terapia Neoadyuvante , Neoplasias Esofágicas/tratamiento farmacológico , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Estudios Retrospectivos
19.
Mol Biol Rep ; 39(3): 2275-83, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21647549

RESUMEN

A chalcone reductase (CHR) gene was isolated from Astragalus membranaceus Bge. var. mongholicus (Bge.) Hsiao (A. mongholicus). The full-length cDNA of A. mongholicus CHR, designated as Amchr (GenBank accession No. HM357239), was 1196 bp long. It had a 957 bp open reading frame encoding a 318-amino acid protein of 35 kDa, a 67 bp 5' non-coding region and a 172 bp 3'-untranslated region. The putative AmCHR protein showed striking similarity to CHR from other leguminous species. Two-dimensional structure modeling showed that AmCHR consisted of 45.28% α-helix, 10.38% extended strand and 44.34% random coil. Prediction showed that three-dimensional AmCHR was a global protein containing an aldo-ket-red domain, with a putative Asp-Tyr-Lys-His catalytic tetrad in the center. The AmCHR gene was 1251 bp long, consisting of three exons and two introns. Intron I was 125 bp and intron II was 169 bp long. Southern blot analysis indicated that Amchr belonged to a small multigene family. Under natural conditions, Amchr was expressed differentially in the root, stem and leaf tissues of A. mongholicus, with a preferential expression in the root. The recombinant AmCHR protein was successfully expressed in Escherichia coli strain BL21 with pET42a vector. The result showed that the expressed AmCHR protein had molecular weight of about 35 kDa, which matched the size of the predicted protein by bioinformatic analysis. This study opened avenues towards understanding of the function of AmCHR protein and the role of the Amchr gene in the calycosin-7-O-ß-D: -glucoside branch pathway in A. mongholicus.


Asunto(s)
Oxidorreductasas de Alcohol/genética , Oxidorreductasas de Alcohol/metabolismo , Astragalus propinquus/enzimología , Secuencia de Bases , Southern Blotting , Clonación Molecular , Biología Computacional , ADN Complementario/genética , Perfilación de la Expresión Génica , Datos de Secuencia Molecular , Estructura Molecular , Análisis de Secuencia de ADN
20.
Curr Microbiol ; 64(1): 34-42, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21993713

RESUMEN

To improve our understanding of the changes in bacterial and fungal diversity in natural pine and planted forests in subtropical region of China, we examined bacterial and fungal communities from a native and a nearby planted pine forest of the Mt. Lushan by constructing clone libraries of 16S and 18S rRNA genes. For bacterial communities, Proteobacteria and Acidobacteria were dominant bacterial taxa in both two types of forest soils. The Shannon-Wiener diversity index, rarefaction curve analysis, and LibShuff analysis suggest that these two forests contained similar diversity of bacterial communities. Low soil acidity (pH ≈ 4) of our study forests might be one of the most important selection factors determining growth of acidophilic Acidobacteria and Proteobacteria. However, the natural forest harbored greater level of fungal diversity than the planted forest according to the Shannon-Wiener diversity index and rarefaction curve analysis. Basidiomycota and Ascomycota were dominant fungal taxa in the soils of natural and planted forests, respectively. Our results suggest that fungal community was more sensitive than the bacterial community in characterizing the differences in plant cover impacts on the microbial flora in the natural and planted forests. The natural and planted forests may function differently due to the differences in soil fungal diversity and relative abundance.


Asunto(s)
Bacterias/aislamiento & purificación , Hongos/aislamiento & purificación , Pinus/microbiología , Microbiología del Suelo , Árboles/microbiología , Agricultura , Bacterias/clasificación , Bacterias/genética , China , Hongos/clasificación , Hongos/genética , Datos de Secuencia Molecular , Filogenia , Pinus/crecimiento & desarrollo , Suelo/análisis , Árboles/crecimiento & desarrollo
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