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1.
BMC Plant Biol ; 24(1): 23, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38166728

RESUMEN

BACKGROUND: Spiraea L. is a genus comprising approximately 90 species that are distributed throughout the northern temperate regions. China is recognized as the center of species diversity for this genus, hosting more than 70 species, including 47 endemic species. While Spiraea is well-known for its ornamental value, its taxonomic and phylogenetic studies have been insufficient. RESULTS: In this study, we conducted sequencing and assembly of the plastid genomes (plastomes) of 34 Asiatic Spiraea accessions (representing 27 Asiatic Spiraea species) from China and neighboring regions. The Spiraea plastid genome exhibits typical quadripartite structures and encodes 113-114 genes, including 78-79 protein-coding genes (PCGs), 30 tRNA genes, and 4 rRNA genes. Linear regression analysis revealed a significant correlation between genome size and the length of the SC region. By the sliding windows method, we identified several hypervariable hotspots within the Spiraea plastome, all of which were localized in the SC regions. Our phylogenomic analysis successfully established a robust phylogenetic framework for Spiraea, but it did not support the current defined section boundaries. Additionally, we discovered that the genus underwent diversification after the Early Oligocene (~ 30 Ma), followed by a rapid speciation process during the Pliocene and Pleistocene periods. CONCLUSIONS: The plastomes of Spiraea provided us invaluable insights into its phylogenetic relationships and evolutionary history. In conjunction with plastome data, further investigations utilizing other genomes, such as the nuclear genome, are urgently needed to enhance our understanding of the evolutionary history of this genus.


Asunto(s)
Genoma del Cloroplasto , Genoma de Plastidios , Rosaceae , Spiraea , Filogenia , Evolución Molecular , Genoma del Cloroplasto/genética
2.
Cell Biol Int ; 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38563483

RESUMEN

Daurisoline (DS) is an isoquinoline alkaloid that exerts anticancer activities in various cancer cells. However, the underlying mechanisms through which DS affects the survival of breast cancer cells remain poorly understood. Therefore, the present study was undertaken to investigate the potential anticancer effect of DS on breast cancer cells and reveal the mechanism underlying the enhanced tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis by DS. Cell counting kit-8 (CCK-8) and 5-ethynyl-2-deoxyuridine (EdU) assay were used to evaluate the ability of cell proliferation. Flow cytometry was selected to examine the cell cycle distribution. TUNEL assay was used to detect the cell apoptosis. The protein expression was measured by Western blot analysis. DS was found to reduce the cell viability and suppress the proliferation of MCF-7 and MDA-MB-231 cells by causing G1 phase cell cycle arrest. DS could trigger apoptosis by promoting the cleavage of caspase-8 and PARP. The phosphorylation of ERK, JNK, and p38MAPK was upregulated clearly following DS treatment. Notably, SP600125 (JNK inhibitor) pretreatment significantly abrogated DS-induced PARP cleavage. DS inactivated Akt/mTOR and Wnt/ß-catenin signaling pathway and upregulated the expression of ER stress-related proteins. Additionally, DS amplified TRAIL-caused viability reduction and apoptosis in breast cancer cells. Mechanismly, DS upregulated the protein level of DR4 and DR5, and knockdown of DR5 attenuated the cotreatment-induced cleavage of PARP. Inhibition of JNK could block DS-induced upregulation of DR5. This study provides valuable insights into the mechanisms of DS inhibiting cell proliferation, triggering apoptosis, and enhancing TRAIL sensitivity of breast cancer cells.

3.
BMC Plant Biol ; 23(1): 359, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37452336

RESUMEN

BACKGROUND: Lysimachia L., the second largest genus within the subfamily Myrsinoideae of Primulaceae, comprises approximately 250 species worldwide. China is the species diversity center of Lysimachia, containing approximately 150 species. Despite advances in the backbone phylogeny of Lysimachia, species-level relationships remain poorly understood due to limited genomic information. This study analyzed 50 complete plastomes for 46 Lysimachia species. We aimed to identify the plastome structure features and hypervariable loci of Lysimachia. Additionally, the phylogenetic relationships and phylogenetic conflict signals in Lysimachia were examined. RESULTS: These fifty plastomes within Lysimachia had the typical quadripartite structure, with lengths varying from 152,691 to 155,784 bp. Plastome size was positively correlated with IR and intron length. Thirteen highly variable regions in Lysimachia plastomes were identified. Additionally, ndhB, petB and ycf2 were found to be under positive selection. Plastid ML trees and species tree strongly supported that L. maritima as sister to subg. Palladia + subg. Lysimachia (Christinae clade), while the nrDNA ML tree clearly placed L. maritima and subg. Palladia as a sister group. CONCLUSIONS: The structures of these plastomes of Lysimachia were generally conserved, but potential plastid markers and signatures of positive selection were detected. These genomic data provided new insights into the interspecific relationships of Lysimachia, including the cytonuclear discordance of the position of L. maritima, which may be the result of ghost introgression in the past. Our findings have established a basis for further exploration of the taxonomy, phylogeny and evolutionary history within Lysimachia.


Asunto(s)
Genoma de Plastidios , Primulaceae , Primulaceae/genética , Filogenia , Lysimachia , Plastidios/genética , Evolución Molecular
4.
Sensors (Basel) ; 23(4)2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36850798

RESUMEN

In estimation of linear systems, an efficient event-triggered Kalman filter algorithm is proposed. Based on the hypothesis test of Gaussian distribution, the significance of the event-triggered threshold is given. Based on the threshold, the actual trigger frequency of the estimated system can be accurately set. Combining the threshold and the proposed event-triggered mechanism, an event-triggered Kalman filter is proposed and the approximate estimation accuracy can also be calculated. Whether it is a steady system or a time-varying system, the proposed algorithm can reasonably set the threshold according to the required accuracy in advance. The proposed event-triggered estimator not only effectively reduces the communication cost, but also has high accuracy. Finally, simulation examples verify the correctness and effectiveness of the proposed algorithm.

5.
Sensors (Basel) ; 23(9)2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37177770

RESUMEN

Energy-optimal adaptive cruise control (EACC) is becoming increasingly popular due to its ability to save energy. Considering the negative impacts of system noise on the EACC, an improved modified model predictive control (MPC) is proposed, which combines the Sage-Husaadaptive Kalman filter (SHAKF), the cubature Kalman filter (CKF), and the back-propagation neural network (BPNN). The proposed MPC improves safety and tracking performance while further reducing energy consumption. The final simulation results show that the proposed algorithm has a stronger energy-saving capability compared to previous studies and always maintains an appropriate relative distance and relative speed to the vehicle in front, verifying the effectiveness of the proposed algorithm.

6.
J Cell Mol Med ; 26(5): 1606-1620, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35106915

RESUMEN

Acetylshikonin (ASK) is a natural naphthoquinone derivative of traditional Chinese medicine Lithospermum erythrorhyzon. It has been reported that ASK has bactericidal, anti-inflammatory and antitumour effects. However, whether ASK induces apoptosis and autophagy in acute myeloid leukaemia (AML) cells and the underlying mechanism are still unclear. Here, we explored the roles of apoptosis and autophagy in ASK-induced cell death and the potential molecular mechanisms in human AML HL-60 cells. The results demonstrated that ASK remarkably inhibited the cell proliferation, viability and induced apoptosis in HL-60 cells through the mitochondrial pathway, and ASK promoted cell cycle arrest in the S-phase. In addition, the increased formation of autophagosomes, the turnover from light chain 3B (LC3B) I to LC3B II and decrease of P62 suggested the induction of autophagy by ASK. Furthermore, ASK significantly decreased PI3K, phospho-Akt and p-p70S6K expression, while enhanced phospho-AMP-activated protein kinase (AMPK) and phospho-liver kinase B1(LKB1) expression. The suppression of ASK-induced the conversion from LC3B I to LC3B II caused by the application of inhibitors of AMPK (compound C) demonstrated that ASK-induced autophagy depends on the LKB1/AMPK pathway. These data suggested that the autophagy induced by ASK were dependent on the activation of LKB1/AMPK signalling and suppression of PI3K/Akt/mTOR pathways. The cleavage of the apoptosis-related markers caspase-3 and caspase-9 and the activity of caspase-3 induced by ASK were markedly reduced by inhibitor of AMPK (compound C), an autophagy inhibitor 3-methyladenine (3-MA) and another autophagy inhibitor chloroquine (CQ). Taken together, our data reveal that ASK-induced HL-60 cell apoptosis is dependent on the activation of autophagy via the LKB1/AMPK and PI3K/Akt-regulated mTOR signalling pathways.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Proteínas Proto-Oncogénicas c-akt , Proteínas Quinasas Activadas por AMP/metabolismo , Antraquinonas , Apoptosis , Autofagia , Caspasa 3 , Proliferación Celular , Células HL-60 , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/metabolismo
7.
BMC Genomics ; 23(1): 770, 2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36424546

RESUMEN

BACKGROUND: Although knowledge of the sizes, contents, and forms of plant mitochondrial genomes (mitogenomes) is increasing, little is known about the mechanisms underlying their structural diversity. Evolutionary information on the mitogenomes of Primula, an important ornamental taxon, is more limited than the information on their nuclear and plastid counterparts, which has hindered the comprehensive understanding of Primula mitogenomic diversity and evolution. The present study reported and compared three Primula mitogenomes and discussed the size expansion of mitogenomes in Ericales. RESULTS: Mitogenome master circles were sequenced and successfully assembled for three Primula taxa and were compared with publicly available Ericales mitogenomes. The three mitogenomes contained similar gene contents and varied primarily in their structures. The Primula mitogenomes possessed relatively high nucleotide diversity among all examined plant lineages. In addition, high nucleotide diversity was found among Primula species between the Mediterranean and Himalaya-Hengduan Mountains. Most predicted RNA editing sites appeared in the second amino acid codon, increasing the hydrophobic character of the protein. An early stop in atp6 caused by RNA editing was conserved across all examined Ericales species. The interfamilial relationships within Ericales and interspecific relationships within Primula could be well resolved based on mitochondrial data. Transfer of the two longest mitochondrial plastid sequences (MTPTs) occurred before the divergence of Primula and its close relatives, and multiple independent transfers could also occur in a single MTPT sequence. Foreign sequence [MTPTs and mitochondrial nuclear DNA sequences (NUMTs)] uptake and repeats were to some extent associated with changes in Ericales mitogenome size, although none of these relationships were significant overall. CONCLUSIONS: The present study revealed relatively conserved gene contents, gene clusters, RNA editing, and MTPTs but considerable structural variation in Primula mitogenomes. Relatively high nucleotide diversity was found in the Primula mitogenomes. In addition, mitogenomic genes, collinear gene clusters, and locally collinear blocks (LCBs) all showed phylogenetic signals. The evolutionary history of MTPTs in Primula was complicated, even in a single MTPT sequence. Various reasons for the size variation observed in Ericales mitogenomes were found.


Asunto(s)
Ericales , Genoma Mitocondrial , Primula , Genoma Mitocondrial/genética , Primula/genética , Filogenia , Ericales/genética , Evolución Molecular , ADN Mitocondrial/genética , Nucleótidos
8.
Arch Insect Biochem Physiol ; 109(1): e21853, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34820894

RESUMEN

Corn leaf aphid Rhopalosiphum maidis (Fitch) can feed on various cereal crops and transmit viruses that may cause serious economic losses. To test the impact of both host plant species and age on R. maidis, as well as the proteomic difference of diverse populations, we first investigated the survival and reproduction of six R. maidis populations (i.e., LF, HF, GZ, DY, BJ, and MS) via a direct observation method in the laboratory on 10 and 50 cm high maize seedlings, and 10 cm high barley seedlings. Then a proteomic approach was implemented to identify the differentially expressed proteins from both aphids and endosymbionts of BJ and MS populations. Results indicated that the BJ population performed significantly better than the others on both barley and 50 cm high maize seedlings, while no population could survive on 10 cm high maize seedlings. The proteomic results demonstrated that the expression levels of myosin heavy chain (muscle isoform X12) (spot 781) and peroxidase (spot 1383) were upregulated, while ATP-dependent protease Hsp 100 (spot 2137) from Hamiltonella defensa and protein SYMBAF (spot 2703) from Serratia symbiotica were downregulated in the BJ population when compared to expression levels of the MS population. We hypothesize that the fatalness observed on 10 cm high maize seedlings may be caused by secondary metabolites that are synthesized by the seedlings and the MS population of R. maidis should be more stress-resistant than the BJ population. Our results also provide insights for understanding the interaction between host plants and aphids.


Asunto(s)
Áfidos/metabolismo , Proteoma , Animales , Áfidos/microbiología , Áfidos/fisiología , Enterobacteriaceae/metabolismo , Hordeum/parasitología , Proteínas de Insectos/metabolismo , Hojas de la Planta/parasitología , Serratia/metabolismo , Simbiosis , Zea mays/parasitología
9.
Prenat Diagn ; 42(10): 1323-1331, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35938586

RESUMEN

OBJECTIVE: To explore whether the post-left atrium space (PLAS) ratio would be useful for prenatal diagnosis of total anomalous pulmonary venous connection (TAPVC) using echocardiography and artificial intelligence. METHODS: We retrospectively included 642 frames of four-chamber views from 319 fetuses (32 with TAPVC and 287 without TAPVC) in end-systolic and end-diastolic periods with multiple apex directions. The average gestational age was 25.6 ± 2.7 weeks. No other cardiac or extracardiac malformations were observed. The dataset was divided into a training set (n = 540; 48 with TAPVC and 492 without TAPVC) and test set (n = 102; 20 with TAPVC and 82 without TAPVC). The PLAS ratio was defined as the ratio of the epicardium-descending aortic distance to the center of the heart-descending aortic distance. Supervised learning was used in DeepLabv3+, FastFCN, PSPNet, and DenseASPP segmentation models. The area under the curve (AUC) was used on the test set. RESULTS: Expert annotations showed that this ratio was not related to the period or apex direction. It was higher in the TAPVC group than in the control group detected by the expert and the four models. The AUC of expert annotations, DeepLabv3+, FastFCN, PSPNet, and DenseASPP were 0.977, 0.941, 0.925, 0.856, and 0.887, respectively. CONCLUSION: Segmentation models achieve good diagnostic accuracy for TAPVC based on the PLAS ratio.


Asunto(s)
Venas Pulmonares , Síndrome de Cimitarra , Inteligencia Artificial , Femenino , Feto , Atrios Cardíacos/diagnóstico por imagen , Humanos , Lactante , Embarazo , Venas Pulmonares/anomalías , Venas Pulmonares/diagnóstico por imagen , Estudios Retrospectivos , Síndrome de Cimitarra/diagnóstico por imagen , Ultrasonografía Prenatal
10.
Int J Mol Sci ; 20(18)2019 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-31540236

RESUMEN

The Myrsinaceae s.str. clade is a tropical woody representative in Myrsinoideae of Primulaceae and has ca. 1300 species. The generic limits and alignments of this clade are unclear due to the limited number of genetic markers and/or taxon samplings in previous studies. Here, the chloroplast (cp) genomes of 13 taxa within the Myrsinaceae s.str. clade are sequenced and characterized. These cp genomes are typical quadripartite circle molecules and are highly conserved in size and gene content. Three pseudogenes are identified, of which ycf15 is totally absent from five taxa. Noncoding and large single copy region (LSC) exhibit higher levels of nucleotide diversity (Pi) than other regions. A total of ten hotspot fragments and 796 chloroplast simple sequence repeats (SSR) loci are found across all cp genomes. The results of phylogenetic analysis support the notion that the monophyletic Myrsinaceae s.str. clade has two subclades. Non-synonymous substitution rates (dN) are higher in housekeeping (HK) genes than photosynthetic (PS) genes, but both groups have a nearly identical synonymous substitution rate (dS). The results indicate that the PS genes are under stronger functional constraints compared with the HK genes. Overall, the study provides hypervariable molecular markers for phylogenetic reconstruction and contributes to a better understanding of plastid gene evolution in Myrsinaceae s.str. clade.


Asunto(s)
Cloroplastos/genética , Primulaceae/genética , Análisis de Secuencia de ADN/métodos , Evolución Molecular , Tamaño del Genoma , Genoma del Cloroplasto , Repeticiones de Microsatélite , Filogenia , Primulaceae/clasificación , Seudogenes
11.
New Phytol ; 219(1): 436-448, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29663397

RESUMEN

What causes the disparity in biodiversity among regions is a fundamental question in biogeography, ecology, and evolutionary biology. Evolutionary and biogeographic processes (speciation, extinction, dispersal) directly determine species richness patterns, and can be studied using integrative phylogenetic approaches. However, the strikingly high richness of East Asia relative to other Northern Hemisphere regions remains poorly understood from this perspective. Here, for the first time, we test two general hypotheses (older colonization time, faster diversification rate) to explain this pattern, using the plant tribe Lysimachieae (Primulaceae) as a model system. We generated a new time-calibrated phylogeny for Lysimachieae (13 genes, 126 species), to estimate colonization times and diversification rates for each region and to test the relative importance of these two factors for explaining regional richness patterns. We find that neither time nor diversification rates alone explain richness patterns among regions in Lysimachieae. Instead, a new index that combines both factors explains global richness patterns in the group and their high East Asian biodiversity. Based on our results from Lysimachieae, we suggest that the high richness of plants in East Asia may be explained by a combination of older colonization times and faster diversification rates in this region.


Asunto(s)
Biodiversidad , Filogenia , Primulaceae/fisiología , Asia Oriental , Filogeografía , Primulaceae/genética
12.
Sensors (Basel) ; 18(10)2018 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-30261664

RESUMEN

The multi-sensor information fusion particle filter (PF) has been put forward for nonlinear systems with correlated noises. The proposed algorithm uses the Taylor series expansion method, which makes the nonlinear measurement functions have a linear relationship by the intermediary function. A weighted measurement fusion PF (WMF-PF) was put forward for systems with correlated noises by applying the full rank decomposition and the weighted least square theory. Compared with the augmented optimal centralized fusion particle filter (CF-PF), it could greatly reduce the amount of calculation. Moreover, it showed asymptotic optimality as the Taylor series expansion increased. The simulation examples illustrate the effectiveness and correctness of the proposed algorithm.

13.
Int J Mol Sci ; 19(5)2018 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-29693617

RESUMEN

The subfamily Caesalpinioideae of the Fabaceae has long been recognized as non-monophyletic due to its controversial phylogenetic relationships. Cercis chuniana, endemic to China, is a representative species of Cercis L. placed within Caesalpinioideae in the older sense. Here, we report the whole chloroplast (cp) genome of C. chuniana and compare it to six other species from the Caesalpinioideae. Comparative analyses of gene synteny and simple sequence repeats (SSRs), as well as estimation of nucleotide diversity, the relative ratios of synonymous and nonsynonymous substitutions (dn/ds), and Kimura 2-parameter (K2P) interspecific genetic distances, were all conducted. The whole cp genome of C. chuniana was found to be 158,433 bp long with a total of 114 genes, 81 of which code for proteins. Nucleotide substitutions and length variation are present, particularly at the boundaries among large single copy (LSC), inverted repeat (IR) and small single copy (SSC) regions. Nucleotide diversity among all species was estimated to be 0.03, the average dn/ds ratio 0.3177, and the average K2P value 0.0372. Ninety-one SSRs were identified in C. chuniana, with the highest proportion in the LSC region. Ninety-seven species from the old Caesalpinioideae were selected for phylogenetic reconstruction, the analysis of which strongly supports the monophyly of Cercidoideae based on the new classification of the Fabaceae. Our study provides genomic information for further phylogenetic reconstruction and biogeographic inference of Cercis and other legume species.


Asunto(s)
Fabaceae/genética , Genoma del Cloroplasto , Filogenia , Evolución Molecular , Fabaceae/clasificación , Repeticiones de Microsatélite , Sistemas de Lectura Abierta , Polimorfismo Genético
14.
Sensors (Basel) ; 17(10)2017 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-28956862

RESUMEN

We addressed the fusion estimation problem for nonlinear multisensory systems. Based on the Gauss-Hermite approximation and weighted least square criterion, an augmented high-dimension measurement from all sensors was compressed into a lower dimension. By combining the low-dimension measurement function with the particle filter (PF), a weighted measurement fusion PF (WMF-PF) is presented. The accuracy of WMF-PF appears good and has a lower computational cost when compared to centralized fusion PF (CF-PF). An example is given to show the effectiveness of the proposed algorithms.

15.
Inflammopharmacology ; 25(4): 471-484, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28577132

RESUMEN

Our aim was to investigate whether tangeretin, a citrus flavonoid, was able to prevent neuroinflammation and improve dementia in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced rodent model of Parkinson's disease (PD). MPTP-HCl was infused into the substantia nigra pars compacta of male Sprague-Dawley rats. Tangeretin (50, 100 or 200 mg/kg body weight) was administered orally starting 3 days prior to MPTP injection and was continued for 20 days following injection. MPTP-lesioned rats revealed motor dysfunction in bar test and rota rod tests. Deficits in working memory and object recognition function were also observed following MPTP induction. Tangeretin treatment significantly attenuated the memory deficits and improved motor functions and cognition. Immunohistochemical analysis reveals the protective effects of tangeretin against MPTP lesion-induced dopaminergic degeneration and hippocampal neuronal loss. Tangeretin reduced expression of inflammatory mediators-COX-2, iNOS-as well reduced the levels of cytokines-interleukins (IL)-IL-1ß, IL-6 and IL-2. The experimental data suggest tangeretin as an effective candidate drug with potential for prevention and treatment of neuroinflammation and dementia associated with PD.


Asunto(s)
Demencia/tratamiento farmacológico , Flavonas/uso terapéutico , Mediadores de Inflamación/antagonistas & inhibidores , Intoxicación por MPTP/tratamiento farmacológico , Aprendizaje por Laberinto/efectos de los fármacos , Animales , Cognición/efectos de los fármacos , Cognición/fisiología , Demencia/metabolismo , Demencia/psicología , Relación Dosis-Respuesta a Droga , Flavonas/farmacología , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Inflamación/psicología , Mediadores de Inflamación/metabolismo , Intoxicación por MPTP/metabolismo , Intoxicación por MPTP/psicología , Masculino , Aprendizaje por Laberinto/fisiología , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/psicología , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Ratas , Ratas Sprague-Dawley
16.
Molecules ; 21(5)2016 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-27171065

RESUMEN

Primula poissonii (Primulaceae) is a perennial herb, widely distributed in the Hengduan Mountain region of Southwest China. In this study, Roche 454 pyrosequencing was used to isolate microsatellite markers. A total of 4528 unique sequences were identified from 68,070 unique reads. Of these, eighty-seven microsatellite loci were screened for utility using two criteria: successful PCR amplification and variation of these loci within three wild P. poissonii populations. Twenty loci were successfully amplified and exhibited polymorphic alleles. The number of observed alleles ranged from 1 to 9 with an average of 3.5. The observed and expected heterozygosities ranged from 0.087 to 1.000 and from 0.124 to 0.828, respectively. Among these SSR loci, only the P69 locus could not be cross-amplified successfully in two closely related species P. wilsonii and P. anisodora. The microsatellite loci developed in this study will be useful for studying genetic diversity and speciation events between P. poissonii and closely related Primula species.


Asunto(s)
ADN de Plantas/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Repeticiones de Microsatélite , Primula/genética , China , Sitios Genéticos , Marcadores Genéticos , Especiación Genética , Variación Genética , Reacción en Cadena de la Polimerasa , Especificidad de la Especie
17.
J Mol Recognit ; 28(4): 269-76, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25664688

RESUMEN

The binding of programmed death ligand 1 protein (PD-L1) to its receptor programmed death protein 1 (PD-1) mediates immunoevasion in cancer and chronic viral infections, presenting an important target for therapeutic intervention. Several monoclonal antibodies targeting the PD-L1/PD-1 signaling axis are undergoing clinical trials; however, the epitopes of these antibodies have not been described. We have combined orthogonal approaches to localize and characterize the epitope of a monoclonal antibody directed against PD-L1 at good resolution and with high confidence. Limited proteolysis and mass spectrometry were applied to reveal that the epitope resides in the first immunoglobulin domain of PD-L1. Hydrogen-deuterium exchange mass spectrometry (HDX-MS) was used to identify a conformational epitope comprised of discontinuous strands that fold to form a beta sheet in the native structure. This beta sheet presents an epitope surface that significantly overlaps with the PD-1 binding interface, consistent with a desired PD-1 competitive mechanism of action for the antibody. Surface plasmon resonance screening of mutant PD-L1 variants confirmed that the region identified by HDX-MS is critical for the antibody interaction and further defined specific residues contributing to the binding energy. Taken together, the results are consistent with the observed inhibitory activity of the antibody on PD-L1-mediated immune evasion. This is the first report of an epitope for any antibody targeting PD-L1 and demonstrates the power of combining orthogonal epitope mapping techniques.


Asunto(s)
Anticuerpos Monoclonales/química , Antígeno B7-H1/inmunología , Epítopos/análisis , Medición de Intercambio de Deuterio/métodos , Mapeo Epitopo/métodos , Humanos , Espectrometría de Masas/métodos , Proteolisis
18.
Xenobiotica ; 45(11): 1024-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25970816

RESUMEN

1. The clinical use of doxorubicin, an effective anticancer drug, is severely hampered by its cardiotoxicity. Berberine, a botanical alkaloid, has been reported to possess cardioprotective and antitumor effects. In this study, we investigated the cardioprotective effect of berberine on doxorubicin-induced cardiotoxicity and the effect of berberine on the metabolism of doxorubicin. 2. Adult male Sprague-Dawley rats were administered doxorubicin in the presence or absence of berberine for 2 weeks. Administration of berberine effectively prevented doxorubicin-induced body weight reduction and mortality in rats. 3. Berberine reduced the activity of myocardial enzymes, including aspartate aminotransferase (AST), creatine kinase (CK), CK isoenzyme (CK-MB) and lactate dehydrogenase (LDH). Echocardiographic examination further demonstrated that berberine effectively ameliorated cardiac dysfunction induced by doxorubicin. 4. Berberine inhibited the metabolism of doxorubicin in the cytoplasm of rat heart and reduced the accumulation of doxorubicinol (a secondary alcohol metabolite of doxorubicin) in heart. 5. These data showed that berberine alleviated the doxorubicin-induced cardiotoxicity in rats via inhibition of the metabolism of doxorubicin and reduced accumulation of doxorubicinol selectively in hearts.


Asunto(s)
Berberina/farmacología , Cardiomiopatías/congénito , Cardiomiopatías/tratamiento farmacológico , Cardiotoxinas , Doxorrubicina , Animales , Cardiomiopatías/metabolismo , Cardiotoxinas/efectos adversos , Cardiotoxinas/farmacocinética , Cardiotoxinas/farmacología , Doxorrubicina/efectos adversos , Doxorrubicina/farmacocinética , Doxorrubicina/farmacología , Masculino , Ratas , Ratas Sprague-Dawley
19.
Zhonghua Yu Fang Yi Xue Za Zhi ; 49(8): 710-5, 2015 Aug.
Artículo en Zh | MEDLINE | ID: mdl-26733030

RESUMEN

OBJECTIVE: To analyze the status of maternal health behaviors and it's risk factors for Yi-nationality women in poor rural areas of Sichuan province. METHODS: In 2012, multi-stage stratified cluster sampling method was used to select 14 villages of two poor counties in Liangshan Yi-nationality autonomous prefecture Sichuan province. At least 10 women who have infants aged 0-12 months were selected in each simple villages, a total of 284. The structured questionnaire was developed on the basis of the theory of reasoned action. Yi-nationality female college students were trained as investigators. Research indicators included prenatal care rate, hospital delivery rate, postpartum examination rate, socio-demographic characteristics, maternal health care knowledge. χ² test was used to compare the differences of above indicators among different groups. The structural equation model were used to statistical analyze. RESULTS: In the 284 subject women, 51.7% (147/284) women owned more than 2 children, 41.6% (118/284) women were more than 30 years old, 87.3% (248/284) women were illiteracy. The prenatal care rate was 69.7% (197/284), the hospital delivery rate was 26.8% (76/284), and the postnatal check rate was 22.9% (65/284). The influence factors of maternal health behaviors included the number of children, age and education (χ² were 10.92, 13.24, 9.58; P values were 0.027, 0.004, 0.008, respectively).The structural equation model analysis results showed that the maternal health behaviors were directly or indirectly affected by subjective norms (ß = 0.236, P < 0.001), women's cognition (ß = 0.226, P = 0.020) and women's attitudes on maternal health behavior (ß = 0.157, P = 0.001). Among subjective norms, women have high compliance to their husbands (ß = 0.850, P < 0.001), their peers (ß = 0.708, P < 0.001), and their mothers-in-law (ß = 0.636, P < 0.001). CONCLUSION: There were still serious problems in maternal health behaviors for Yi-nationality women in poor rural areas. The main factors included not only the women's cognition and attitudes for maternal health, but also the attitudes of important social relationships.


Asunto(s)
Conductas Relacionadas con la Salud/etnología , Salud Materna/etnología , Población Rural , Niño , China , Etnicidad , Familia , Femenino , Humanos , Lactante , Servicios de Salud Materna , Periodo Posparto , Embarazo , Atención Prenatal , Factores de Riesgo
20.
Protein Expr Purif ; 93: 18-22, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24161563

RESUMEN

Endostatin is a potent anti-angiogenesis compound with efficacy in treating solid tumors and other diseases. However, its clinical application has been hampered by the susceptibility to proteolytic degradation during cell culture production. Here we describe a simple and effective strategy for stabilizing a CHO cell-derived human endostatin Fc fusion. Mass spectrometry analysis of the prominent clipped species revealed that the cleavage sites are located at the N-terminal zinc binding region, which is known to be critical for the structural stability of the molecule. Accordingly, we tested the effect of zinc supplementation on stabilizing the molecule and found that micromolar concentrations of zinc chloride significantly reduced the level of clipping. The protective effect appeared to be mediated via direct interaction between zinc and endostatin, as zinc protects purified endostatin spiked into conditioned medium. Interestingly, copper which is known to have high affinity to endostatin, also prevents degradation. The method provides a robust process for manufacturing Fc-endostatin.

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