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1.
Plant J ; 114(4): 805-823, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36864731

RESUMO

Here, we present a high-quality chromosome-scale genome assembly (2.19 Gb) and annotation of Tetrastigma hemsleyanum, a perennial herbaceous liana native to subtropical China with diverse medicinal applications. Approximately 73% of the genome was comprised of transposable elements (TEs), of which long terminal repeat retrotransposons (LTR-RTs) were a predominant group (69% of the genome). The genome size increase of T. hemsleyanum (relative to Vitis species) was mostly due to the proliferation of LTR-RTs. Of the different modes of gene duplication identified, transposed duplication (TRD) and dispersed duplication (DSD) were the predominant ones. Genes, particularly those involved in the phenylpropanoid-flavonoid (PF) pathway and those associated with therapeutic properties and environmental stress resistance, were significantly amplified through recent tandem duplications. We dated the divergence of two intraspecific lineages in Southwest (SW) versus Central-South-East (CSE) China to the late Miocene (approximately 5.2 million years ago). Of those, the former showed more upregulated genes and metabolites. Based on resequencing data of 38 individuals representing both lineages, we identified various candidate genes related to 'response to stimulus' and 'biosynthetic process', including ThFLS11, which is putatively involved in flavonoid accumulation. Overall, this study provides abundant genomic resources for future evolutionary, ecological, and functional genomics studies in T. hemsleyanum and related species.


Assuntos
Flavonoides , Vitaceae , Vitaceae/genética , Genômica , Cromossomos , Evolução Molecular
2.
BMC Med ; 21(1): 327, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-37635247

RESUMO

BACKGROUND: CD133 is considered a marker for cancer stem cells (CSCs) in several types of tumours, including hepatocellular carcinoma (HCC). Chimeric antigen receptor-specific T (CAR-T) cells targeting CD133-positive CSCs have emerged as a tool for the clinical treatment of HCC, but immunogenicity, the high cost of clinical-grade recombinant viral vectors and potential insertional mutagenesis limit their clinical application. METHODS: CD133-specific CAR-T cells secreting PD-1 blocking scFv (CD133 CAR-T and PD-1 s cells) were constructed using a sleeping beauty transposon system from minicircle technology, and the antitumour efficacy of CD133 CAR-T and PD-1 s cells was analysed in vitro and in vivo. RESULTS: A univariate analysis showed that CD133 expression in male patients at the late stage (II and III) was significantly associated with worse progression-free survival (PFS) (P = 0.0057) and overall survival (OS) (P = 0.015), and a multivariate analysis showed a trend toward worse OS (P = 0.041). Male patients with advanced HCC exhibited an approximately 20-fold higher PD-L1 combined positive score (CPS) compared with those with HCC at an early stage. We successfully generated CD133 CAR-T and PD-1 s cells that could secrete PD-1 blocking scFv based on a sleeping beauty system involving minicircle vectors. CD133 CAR-T and PD-1 s cells exhibited significant antitumour activity against HCC in vitro and in xenograft mouse models. Thus, CD133 CAR-T and PD-1 s cells may be a therapeutically tractable strategy for targeting CD133-positive CSCs in male patients with advanced HCC. CONCLUSIONS: Our study provides a nonviral strategy for constructing CAR-T cells that could also secrete checkpoint blockade inhibitors based on a Sleeping Beauty system from minicircle vectors and revealed a potential benefit of this strategy for male patients with advanced HCC and high CD133 expression (median immunohistochemistry score > 2.284).


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Receptores de Antígenos Quiméricos , Humanos , Masculino , Animais , Camundongos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Receptor de Morte Celular Programada 1 , Receptores de Antígenos Quiméricos/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Modelos Animais de Doenças , Linfócitos T
3.
Biomacromolecules ; 24(5): 1980-1993, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-36716424

RESUMO

In this study, as-is (ca. 12% moisture by mass) and hydrated (50% water by mass) granules of waxy potato (WP), waxy wheat (WW), waxy maize, normal maize, and high-amylose maize (HAM) starches were investigated by using small-angle neutron and X-ray scattering (SANS and SAXS), wide-angle X-ray scattering, and ultra-small-angle neutron scattering. The SANS and SAXS data were fitted using the two-phase stacking model of alternating crystalline and amorphous layers. The partial crystalline lamellar structures inside the growth rings of granules were analyzed based on the inter-lamellar distances, thicknesses of the crystalline lamellae and amorphous layers, thickness polydispersities, and water content in each type of layer. Despite having a longer average chain length of amylopectin, the WP and HAM starches, which had B-type allomorph, had a shorter inter-lamellar distance than the other three starches with A-type allomorph. The WP starch had the most uniform crystalline lamellar thickness. After hydration, the amorphous layers were expanded, resulting in an increase of inter-layer distance. The low-angle intensity upturn in SANS and SAXS was attributed to scattering from interfaces/surfaces of larger structures, such as growth rings and macroscopic granule surfaces. Data analysis methods based on model fitting and 1D correlation function were compared. The study emphasized─owing to inherent packing disorder inside granules─that a comprehensive analysis of different parameters was essential in correlating the microstructures with starch properties.


Assuntos
Amilose , Amido , Amilose/química , Espalhamento a Baixo Ângulo , Difração de Raios X , Amido/química , Amilopectina/química , Água/química
4.
Am J Bot ; 110(5): e16174, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37154532

RESUMO

The autotrophic lifestyle of photosynthetic plants has profoundly shaped their body plan, physiology, and gene repertoire. Shifts to parasitism and heterotrophy have evolved at least 12 times in more than 4000 species, and this transition has consequently left major evolutionary footprints among these parasitic lineages. Features that are otherwise rare at the molecular level and beyond have evolved repetitively, including reduced vegetative bodies, carrion-mimicking during reproduction, and the incorporation of alien genetic material. Here, I propose an integrated conceptual model, referred to as the funnel model, to define the general evolutionary trajectory of parasitic plants and provide a mechanistic explanation for their convergent evolution. This model connects our empirical understanding of gene regulatory networks in flowering plants with classical theories of molecular and population genetics. It emphasizes that the cascading effects brought about by the loss of photosynthesis may be a major force constraining the physiological capacity of parasitic plants and shaping their genomic landscapes. Here I review recent studies on the anatomy, physiology, and genetics of parasitic plants that lend support to this photosynthesis-centered funnel model. Focusing on nonphotosynthetic holoparasites, I elucidate how they may inevitably reach an evolutionary terminal status (i.e., extinction) and highlight the utility of a general, explicitly described and falsifiable model for future studies of parasitic plants.


Assuntos
Fotossíntese , Plantas , Filogenia , Plantas/genética , Fotossíntese/genética , Genoma de Planta , Evolução Molecular
5.
J Phys Chem A ; 127(1): 286-299, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36580040

RESUMO

Bio-hybrid fuels are a promising solution to accomplish a carbon-neutral and low-emission future for the transportation sector. Two potential candidates are the heterocyclic acetals 1,3-dioxane (C4H8O2) and 1,3-dioxolane (C3H6O2), which can be produced from the combination of biobased feedstocks, carbon dioxide, and renewable electricity. In this work, comprehensive experimental and numerical investigations of 1,3-dioxane and 1,3-dioxolane were performed to support their application in internal combustion engines. Ignition delay times and laminar flame speeds were measured to reveal the combustion chemistry on the macroscale, while speciation measurements in a jet-stirred reactor and ethylene-based counterflow diffusion flames provided insights into combustion chemistry and pollutant formation on the microscale. Comparing the experimental and numerical data using either available or proposed kinetic models revealed that the combustion chemistry and pollutant formation differ substantially between 1,3-dioxane and 1,3-dioxolane, although their molecular structures are similar. For example, 1,3-dioxane showed higher reactivity in the low-temperature regime (500-800 K), while 1,3-dioxolane addition to ethylene increased polycyclic aromatic hydrocarbons and soot formation in high-temperature (>800 K) counterflow diffusion flames. Reaction pathway analyses were performed to examine and explain the differences between these two bio-hybrid fuels, which originate from the chemical bond dissociation energies in their molecular structures.


Assuntos
Dioxolanos , Poluentes Ambientais , Hidrocarbonetos Policíclicos Aromáticos , Dioxolanos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Dioxanos/análise
6.
Sensors (Basel) ; 23(12)2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37420652

RESUMO

Acrophobia (fear of heights), a prevalent psychological disorder, elicits profound fear and evokes a range of adverse physiological responses in individuals when exposed to heights, which will lead to a very dangerous state for people in actual heights. In this paper, we explore the behavioral influences in terms of movements in people confronted with virtual reality scenes of extreme heights and develop an acrophobia classification model based on human movement characteristics. To this end, we used wireless miniaturized inertial navigation sensors (WMINS) network to obtain the information of limb movements in the virtual environment. Based on these data, we constructed a series of data feature processing processes, proposed a system model for the classification of acrophobia and non-acrophobia based on human motion feature analysis, and realized the classification recognition of acrophobia and non-acrophobia through the designed integrated learning model. The final accuracy of acrophobia dichotomous classification based on limb motion information reached 94.64%, which has higher accuracy and efficiency compared with other existing research models. Overall, our study demonstrates a strong correlation between people's mental state during fear of heights and their limb movements at that time.


Assuntos
Transtornos Fóbicos , Realidade Virtual , Humanos , Corpo Humano , Medo
7.
Environ Microbiol ; 24(3): 1454-1466, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34967095

RESUMO

Anuran amphibians are susceptible to infection by intestinal nematodes, but the damage and response mechanisms that occur in their intestines after infection are only partially understood. In this study, the intestinal disruption and response mechanisms in Amolops wuyiensis frogs infected with Cosmocercoides wuyiensis n. sp. were revealed through analysis of the intestinal histopathology, digestive enzyme activity, transcriptome and intestinal microbiota. Tissue section analysis showed histological damage and inflammation in the infected intestine, and the digestive enzyme activity indicated a decrease in digestion and absorption of some nutrients. We found that infection led to differences in the intestinal microbiota composition, including lower diversity and symbiotic relationships. The greater relative abundance of the genera Burkholderia and Rhodococcus may enhance intestinal immunity to resist pathogenic infections. A comparison of the transcriptomes of infected and uninfected intestines revealed 1055 differentially expressed genes. GO enrichment and KEGG pathways analyses suggested that the guts of infected C. wuyiensis n. sp. show enhanced complement activation, cell adhesion molecule function, NOD-like receptor signalling pathway activity and other innate immunity responses. Among the adaptive immune responses, the intestinal immune network for IgA production was significantly enriched, and the expression of IL-17D and transforming growth factor beta-1 genes were upregulated in the infected intestine. These results imply that C. wuyiensis n. sp. infection of A. wuyiensis intestine may trigger innate and adaptive immune responses, which reduce the post-infection burden. Furthermore, the intestine of A. wuyiensis may also respond to C. wuyiensis n. sp. infection by increasing metallocarboxypeptidase activity and accelerating smooth muscle contraction.


Assuntos
Intestinos , Nematoides , Animais , Anuros/genética , Imunidade Inata/genética , Nematoides/genética , Transcriptoma
8.
Syst Biol ; 70(3): 491-507, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33169797

RESUMO

The genomic revolution offers renewed hope of resolving rapid radiations in the Tree of Life. The development of the multispecies coalescent model and improved gene tree estimation methods can better accommodate gene tree heterogeneity caused by incomplete lineage sorting (ILS) and gene tree estimation error stemming from the short internal branches. However, the relative influence of these factors in species tree inference is not well understood. Using anchored hybrid enrichment, we generated a data set including 423 single-copy loci from 64 taxa representing 39 families to infer the species tree of the flowering plant order Malpighiales. This order includes 9 of the top 10 most unstable nodes in angiosperms, which have been hypothesized to arise from the rapid radiation during the Cretaceous. Here, we show that coalescent-based methods do not resolve the backbone of Malpighiales and concatenation methods yield inconsistent estimations, providing evidence that gene tree heterogeneity is high in this clade. Despite high levels of ILS and gene tree estimation error, our simulations demonstrate that these two factors alone are insufficient to explain the lack of resolution in this order. To explore this further, we examined triplet frequencies among empirical gene trees and discovered some of them deviated significantly from those attributed to ILS and estimation error, suggesting gene flow as an additional and previously unappreciated phenomenon promoting gene tree variation in Malpighiales. Finally, we applied a novel method to quantify the relative contribution of these three primary sources of gene tree heterogeneity and demonstrated that ILS, gene tree estimation error, and gene flow contributed to 10.0$\%$, 34.8$\%$, and 21.4$\%$ of the variation, respectively. Together, our results suggest that a perfect storm of factors likely influence this lack of resolution, and further indicate that recalcitrant phylogenetic relationships like the backbone of Malpighiales may be better represented as phylogenetic networks. Thus, reducing such groups solely to existing models that adhere strictly to bifurcating trees greatly oversimplifies reality, and obscures our ability to more clearly discern the process of evolution. [Coalescent; concatenation; flanking region; hybrid enrichment, introgression; phylogenomics; rapid radiation, triplet frequency.].


Assuntos
Magnoliopsida , Malpighiales , Fluxo Gênico , Genoma , Humanos , Magnoliopsida/genética , Filogenia
9.
Sensors (Basel) ; 22(22)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36433261

RESUMO

In recent years, research on human psychological stress using wearable devices has gradually attracted attention. However, the physical and psychological differences among individuals and the high cost of data collection are the main challenges for further research on this problem. In this work, our aim is to build a model to detect subjects' psychological stress in different states through electrocardiogram (ECG) signals. Therefore, we design a VR high-altitude experiment to induce psychological stress for the subject to obtain the ECG signal dataset. In the experiment, participants wear smart ECG T-shirts with embedded sensors to complete different tasks so as to record their ECG signals synchronously. Considering the temporal continuity of individual psychological stress, a deep, gated recurrent unit (GRU) neural network is developed to capture the mapping relationship between subjects' ECG signals and stress in different states through heart rate variability features at different moments, so as to build a neural network model from the ECG signal to psychological stress detection. The experimental results show that compared with all comparison methods, our method has the best classification performance on the four stress states of resting, VR scene adaptation, VR task and recovery, and it can be a remote stress monitoring solution for some special industries.


Assuntos
Eletrocardiografia , Dispositivos Eletrônicos Vestíveis , Humanos , Eletrocardiografia/métodos , Redes Neurais de Computação , Frequência Cardíaca/fisiologia , Estresse Psicológico/diagnóstico
10.
Mol Phylogenet Evol ; 165: 107294, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34419587

RESUMO

The Gracilariales is a highly diverse, widely distributed order of red algae (Rhodophyta) that forms a well-supported clade. Aside from their ecological importance, species of Gracilariales provide important sources of agarans and possess bioactive compounds with medicinal and pharmaceutical use. Recent phylogenetic analyses from a small number of genes have greatly advanced our knowledge of evolutionary relationships in this clade, yet several key nodes were not especially well resolved. We assembled a phylogenomic data set containing 79 nuclear genes, 195 plastid genes, and 24 mitochondrial genes from species representing all three major Gracilariales lineages, including: Melanthalia, Gracilariopsis, and Gracilaria sensu lato. This data set leads to a fully-resolved phylogeny of Gracilariales, which is highly-consistent across genomic compartments. In agreement with previous findings, Melanthalia obtusata was sister to a clade including Gracilaria s.l. and Gracilariopsis, which were each resolved as well-supported clades. Our results also clarified the long-standing uncertainty about relationships in Gracilaria s.l., not resolved in single and multi-genes approaches. We further characterized the divergence time, organellar genome architecture, and morphological trait evolution in Gracilarales to better facilitate its taxonomic treatment. Gracilariopsis and Gracilaria s.l. are comparable taxonomic ranks, based on the overlapping time range of their divergence. The genomic structure of plastid and mitochondria is highly conserved within each clade but differs slightly among these clades in gene contents. For example, the plastid gene petP is lost in Gracilaria s.l. and the mitochondrial gene trnH is in different positions in the genome of Gracilariopsis and Gracilaria s.l. Our analyses of ancestral character evolution provide evidence that the main characters used to delimitate genera in Gracilariales, such as spermatangia type and features of the cystocarp's anatomy, overlap in subclades of Gracilaria s.l. We discuss the taxonomy of Gracilariales in light of these results and propose an objective and practical classification, which is in agreement with the criteria of monophyly, exclusive characters, predictability and nomenclatural stability.


Assuntos
Gracilaria , Rodófitas , Genes Mitocondriais , Gracilaria/genética , Filogenia , Plastídeos/genética , Rodófitas/genética
11.
J Med Internet Res ; 22(4): e17089, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32314971

RESUMO

BACKGROUND: The application of telemedicine in home pulmonary rehabilitation interventions for the management of patients with chronic obstructive pulmonary disease (COPD) has achieved promising results. OBJECTIVE: This study aimed to develop a WeChat official account (Pulmonary Internet Explorer Rehabilitation [PeR]) based on social media. It further evaluated the effect of PeR on the quality of life, symptoms, and exercise self-efficacy of patients with COPD. METHODS: The functional modules of PeR were developed by a multidisciplinary team according to the electronic health-enhanced chronic care model (eCCM) components. A total of 106 patients were randomly selected (53 in the PeR group and 53 in the outpatient face-to-face group [FtF]). Pulmonary rehabilitation intervention was conducted for 3 months, and the outcome was observed for 3 months. The primary outcome was patient quality of life measured with the COPD assessment test (CAT). The secondary outcomes were evaluated using the modified Medical Research Council scale (mMRC), exercise self-regulatory efficacy scale (Ex-SRES), and St George's Respiratory Questionnaire (SGRQ). RESULTS: The intention-to-treat analysis was used in the study. A total of 94 participants completed the 6-month pulmonary rehabilitation program. No statistically significant differences were observed in CAT (F1,3=7.78, P=.001), Ex-SRES (F1,3=21.91, P<.001), and mMRC scores (F1,3=29.64, P<.001) between the two groups with the variation in time tendency. The Ex-SRES score had a significant effect on the CAT score (P=.03). The partial regression coefficient of Ex-SRES to CAT was 0.81, and Exp (B) was 2.24. CONCLUSIONS: The telemedicine technology was effective using the eCCM combined with a behavioral intervention strategy centering on self-efficacy. Pulmonary rehabilitation at home through PeR and FtF could improve the sense of self-efficacy and quality of life and alleviate symptoms in patients with COPD. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR1900022770; https://tinyurl.com/tmmvpq3.


Assuntos
Doença Pulmonar Obstrutiva Crônica/reabilitação , Qualidade de Vida/psicologia , Telemedicina/métodos , Idoso , Feminino , Humanos , Masculino , Inquéritos e Questionários
12.
Appl Math Model ; 86: 404-423, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34219864

RESUMO

In this paper, a multi-scale mathematical model for environmentally transmitted diseases is proposed which couples the pathogen-immune interaction inside the human body with the disease transmission at the population level. The model is based on the nested approach that incorporates the infection-age-structured immunological dynamics into an epidemiological system structured by the chronological time, the infection age and the vaccination age. We conduct detailed analysis for both the within-host and between-host disease dynamics. Particularly, we derive the basic reproduction number R 0 for the between-host model and prove the uniform persistence of the system. Furthermore, using carefully constructed Lyapunov functions, we establish threshold-type results regarding the global dynamics of the between-host system: the disease-free equilibrium is globally asymptotically stable when R 0 < 1, and the endemic equilibrium is globally asymptotically stable when R 0 > 1. We explore the connection between the within-host and between-host dynamics through both mathematical analysis and numerical simulation. We show that the pathogen load and immune strength at the individual level contribute to the disease transmission and spread at the population level. We also find that, although the between-host transmission risk correlates positively with the within-host pathogen load, there is no simple monotonic relationship between the disease prevalence and the individual pathogen load.

13.
J Franklin Inst ; 357(12): 8008-8034, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34219794

RESUMO

A new mathematical model is formulated to investigate the transmission dynamics of cholera under vaccination, with a focus on the impact of vaccination age. The basic reproduction number is derived and proved to be a sharp control threshold determining whether or not the infection is persistent. We conduct a rigorous analysis on the local and global stability properties of the equilibria in system. Meanwhile, we compare the results to those of the simplified model based on ordinary differential equations where the effects of vaccination age are not incorporated. Numerical simulation results verify our analytical findings.

14.
New Phytol ; 221(1): 565-576, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30030969

RESUMO

Whole-genome duplications (WGDs) are widespread and prevalent in vascular plants and frequently coincide with major episodes of global and climatic upheaval, including the mass extinction at the Cretaceous-Tertiary boundary (c. 65 Ma) and during more recent periods of global aridification in the Miocene (c. 10-5 Ma). Here, we explore WGDs in the diverse flowering plant clade Malpighiales. Using transcriptomes and complete genomes from 42 species, we applied a multipronged phylogenomic pipeline to identify, locate, and determine the age of WGDs in Malpighiales using three means of inference: distributions of synonymous substitutions per synonymous site (Ks ) among paralogs, phylogenomic (gene tree) reconciliation, and a likelihood-based gene-count method. We conservatively identify 22 ancient WGDs, widely distributed across Malpighiales subclades. Importantly, these events are clustered around the Eocene-Paleocene transition (c. 54 Ma), during which time the planet was warmer and wetter than any period in the Cenozoic. These results establish that the Eocene Climatic Optimum likely represents a previously unrecognized period of prolific WGDs in plants, and lends further support to the hypothesis that polyploidization promotes adaptation and enhances plant survival during episodes of global change, especially for tropical organisms like Malpighiales, which have tight thermal tolerances.


Assuntos
Genoma de Planta , Malpighiales/genética , Filogenia , Adaptação Fisiológica , Clima , Funções Verossimilhança , Malpighiales/fisiologia
15.
Mol Phylogenet Evol ; 134: 142-151, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30743062

RESUMO

Clusieae is an exclusively Neotropical tribe in the family Clusiaceae sensu stricto. Although tribes within Clusiaceae are morphologically and phylogenetically well-delimited, resolution among genera within these tribes remains elusive. The tribe Clusieae includes an estimated ∼500 species distributed among five genera: Chrysochlamys, Clusia, Dystovomita, Tovomita, and Tovomitopsis. In this study, we used nearly complete plastid genomes from 30 exemplar Clusieae species representing all genera recognized, plus two outgroups to infer the phylogeny of the tribe using Maximum Likelihood and Bayesian Inference. For comparison, we also inferred a phylogeny from the nuclear Internal Transcribed Spacer (ITS) region using the same methods. Our study corroborates earlier findings that Clusia is monophyletic while Tovomita is not. It also provides additional support to the hypothesis that Chrysochlamys and Tovomitopsis are not closely related despite gross morphological similarity. Tovomita is divided into three distantly related clades: (i) core Tovomita (including the type T. guianensis), (ii) T. croatii, and (iii) the T. weddelliana species complex. Members of the T. weddelliana complex are isolated from the core Tovomita, and placed in a well-supported clade that is sister to a clade composed of Chrysochlamys plus Clusia. Tovomita croatii is nested within Chrysochlamys. We propose taxonomic revisions to accommodate our phylogenetic findings, including the description of the new genus Arawakia, which includes the 18 species formerly recognized in the T. weddelliana species complex. Lectotypes are also designated for nine species (i.e., Arawakia angustata, A. lanceolata, A. lingulata, A. longicuneata, A. macrocarpa, A. oblanceolata, A. pithecobia, A. rhizophoroides, and A. weddelliana), and a taxonomic key for the identification of the six genera of Clusieae recognized is presented.


Assuntos
Clusiaceae/genética , Genomas de Plastídeos , Teorema de Bayes , Clusiaceae/anatomia & histologia , Flores/anatomia & histologia , Frutas/anatomia & histologia , Funções Verossimilhança , Filogenia
16.
Protein Expr Purif ; 163: 105448, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31279833

RESUMO

The bacterial RNA polymerase (RNAP) is a large, complex molecular machine that is the engine of gene expression. Despite global conservation in their structures and function, RNAPs from different bacteria can have unique features in promoter and transcription factor recognition. Therefore, availability of purified RNAP from different bacteria is key to understanding these species-specific aspects and will be valuable for antibiotic drug discovery. Pseudomonas aeruginosa is one of the leading causes of hospital and community acquired infections worldwide - making the organism an important public health pathogen. We developed a method for producing high quantities of highly pure and active recombinant P. aeruginosa str. PAO1 RNAP core and holoenzyme complexes that employed two-vector systems for expressing the core enzyme (α, ß, ß', and ω subunits) and for expressing the holoenzyme complex (core + σ70). Unlike other RNAP expression approaches, we used a low temperature autoinduction system in E. coli with T7 promoters that produced high cell yields and stable protein expression. The purification strategy comprised of four chromatographic separation steps (metal chelate, heparin, and ion-exchange) with yields of up to 11 mg per 500 mL culture. Purified holoenzyme and reconstituted holoenzyme from core and σ70 were highly active at transcribing both small and large-sized DNA templates, with a determined elongation rate of ~18 nt/s for the holoenzyme. The successful purification of the P. aeruginosa RNAP provides a gateway for studies focusing on in vitro transcriptional regulation in this pathogen.


Assuntos
RNA Polimerases Dirigidas por DNA/isolamento & purificação , Holoenzimas/isolamento & purificação , Pseudomonas aeruginosa/enzimologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Clonagem Molecular/métodos , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/genética , Holoenzimas/genética , Holoenzimas/metabolismo , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/isolamento & purificação , Complexos Multienzimáticos/metabolismo , Pseudomonas aeruginosa/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
17.
Med Sci Monit ; 25: 786-793, 2019 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-30685768

RESUMO

BACKGROUND Obstructive sleep apnea (OSA) is associated with many cardiovascular disorders. Intermittent hypoxia (IH) is a key pathological hallmark of OSA. This study was conducted to evaluate the potential therapeutic effects and the associated mechanisms of adiponectin (APN) on IH induced human adult cardiac myocytes (HACMs) injury. MATERIAL AND METHODS HACMs were exposed to normoxia or IH (1% to 21% O2) using a novel cell culture bio-reactor with gas-permeable membranes. Cell viability was detected by Cell Counting Kit-8 assay. Cell membrane integrity was assessed by the detection of lactate dehydrogenase (LDH) release. Cell apoptosis was analyzed by flow cytometry. Malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) levels were determined using specific assay kits. P-AMPK (AMP-activated protein kinase), p-LKB1, and p-p65 protein levels were measured by western blotting. Pro-inflammatory factors including interleukin (IL)-1ß, IL-6, IL-8 expressions were detected by enzyme-linked immunosorbent assay and quantitative real-time polymerase chain reaction. RESULTS The results showed that APN had no cytotoxic to HACMs. Compared with the control group, HACMs cell viability significantly decreased, LDH release increased and cell apoptosis increased in the IH group. The levels of IL-1ß, IL-6, IL-8, MDA, and p-p65 were higher, while the levels of SOD, GSH-Px, p-AMPK, and p-LKB1 were lower in HACMs cells in the IH group than that in the control group. However, APN treatment significantly rescued these effects compared with the IH group in a dose-dependent manner. CONCLUSIONS In conclusion, these results indicated that APN protected against IH induced HACMs injury possibly mediated by AMPK and NF-κB pathway.


Assuntos
Adiponectina/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Adiponectina/metabolismo , Adulto , Apoptose , Western Blotting , Hipóxia Celular/fisiologia , Glutationa Peroxidase/metabolismo , Traumatismos Cardíacos/metabolismo , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , L-Lactato Desidrogenase/metabolismo , Malondialdeído/metabolismo , Miócitos Cardíacos/patologia , Cultura Primária de Células , Apneia Obstrutiva do Sono/metabolismo , Apneia Obstrutiva do Sono/patologia , Superóxido Dismutase/metabolismo
18.
Zhongguo Yi Liao Qi Xie Za Zhi ; 43(5): 313-317, 2019 Sep 30.
Artigo em Zh | MEDLINE | ID: mdl-31625324

RESUMO

The ultrasound endoscopic probes with very small size transducers are normally imaging by focused ultrasound beamforming technology. So the imaging frame rate is not very high, which cannot meet the needs of some clinical applications based on high imaging rate. In recent years, plane-wave ultrafast imaging technology can obtain high image frame rate and guarantee the image quality. In this paper, a plane wave ultra-fast imaging technique based on a home-made small line array ultrasound transducer is presented. Feasibility of the method is verified by simulation estimations and phantom experiments. The results show that for the small size transducer design of plane wave ultrafast imaging, it is necessary to fully consider the combination of the array element width and the number of array elements. So that a good plane wave imaging quality can be obtained. It lays a foundation for the ultra-fast imaging of plane wave in the interventional ultrasound imaging and ultrasound endoscopy.


Assuntos
Transdutores , Ultrassonografia , Imagens de Fantasmas , Ultrassonografia/instrumentação
19.
Med Sci Monit ; 24: 1574-1580, 2018 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-29549235

RESUMO

BACKGROUND In the present study, we aimed to investigate the effects of sinomenine (SIN) on chronic intermittent hypoxia (CIH)- induced lung injury in rats, and to explore the underlying mechanisms. MATERIAL AND METHODS To perform the investigation, a CIH rat model was established. ELISA assay was applied to detect the level of inflammatory cytokines. Oxidative stress bio-markers (MDA, SOD, and CAT) were determined in lung tissues. In addition, the expression level of NADPH oxidase 2 (Nox2) was analyzed by Western blotting and qRT-PCR, respectively. RESULTS The results showed that compared with other groups, more obvious pulmonary pathological changes were observed in the CIH group. The level of inflammatory cytokines in the CIH group was markedly higher than that in the control and Con-S groups. Compared with the control and Con-S groups, oxidative stress was notably increased in the CIH group. Expression of Nox2 was also increased in the CIH group. The effects caused by CIH in rats were attenuated by SIN treatment. CONCLUSIONS SIN can reverse chronic intermittent hypoxia-induced lung injury through inhibiting inflammation and oxidative stress.


Assuntos
Hipóxia/complicações , Inflamação/tratamento farmacológico , Inflamação/patologia , Lesão Pulmonar/tratamento farmacológico , Lesão Pulmonar/etiologia , Morfinanos/uso terapêutico , Estresse Oxidativo , Animais , Doença Crônica , Citocinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Hipóxia/patologia , Mediadores da Inflamação/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Lesão Pulmonar/patologia , Masculino , Camundongos , Morfinanos/farmacologia , NADPH Oxidases/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
20.
Artigo em Inglês | MEDLINE | ID: mdl-30130379

RESUMO

The left-behind experience refers to the experience of children who were taken care of by caregivers in their hometowns for ≥6 months before reaching age 18, as one or both parents left the rural hometown for better paying jobs in bigger cities. The current study was conducted with college students to test the effect of the left-behind experience on self-efficacy. The General Self-Efficacy Scale and a questionnaire designed by the authors were adopted for a survey of 200 Chinese college students in their final year of university. Of 200 students, 72 (36%) students had ≥6 months of left-behind experience before reaching age 18. Results did not show statistically significant difference in self-efficacy between college students with or without left-behind experience (p > 0.05). In addition, researchers found no significant difference in self-efficacy between college students with left-behind experience from different backgrounds. Further research and focus on this area is necessary. [Journal of Psychosocial Nursing and Mental Health Services, xx(x), xx-xx.].

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