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1.
Plant Cell ; 36(5): 1637-1654, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38114096

RESUMEN

MicroRNAs (miRNAs) are a class of nonprotein-coding short transcripts that provide a layer of post-transcriptional regulation essential to many plant biological processes. MiR858, which targets the transcripts of MYB transcription factors, can affect a range of secondary metabolic processes. Although miR858 and its 187-nt precursor have been well studied in Arabidopsis (Arabidopsis thaliana), a systematic investigation of miR858 precursors and their functions across plant species is lacking due to a problem in identifying the transcripts that generate this subclass. By re-evaluating the transcript of miR858 and relaxing the length cut-off for identifying hairpins, we found in kiwifruit (Actinidia chinensis) that miR858 has long-loop hairpins (1,100 to 2,100 nt), whose intervening sequences between miRNA generating complementary sites were longer than all previously reported miRNA hairpins. Importantly, these precursors of miR858 containing long-loop hairpins (termed MIR858L) are widespread in seed plants including Arabidopsis, varying between 350 and 5,500 nt. Moreover, we showed that MIR858L has a greater impact on proanthocyanidin and flavonol levels in both Arabidopsis and kiwifruit. We suggest that an active MIR858L-MYB regulatory module appeared in the transition of early land plants to large upright flowering plants, making a key contribution to plant secondary metabolism.


Asunto(s)
Actinidia , Arabidopsis , Regulación de la Expresión Génica de las Plantas , MicroARNs , ARN de Planta , MicroARNs/genética , MicroARNs/metabolismo , Actinidia/genética , Actinidia/metabolismo , Arabidopsis/genética , ARN de Planta/genética , ARN de Planta/metabolismo , Semillas/genética , Semillas/metabolismo , Secuencia de Bases
2.
Plant J ; 119(2): 1059-1072, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38761127

RESUMEN

Most of kiwifruit cultivars (e.g. Actinidia chinensis cv. Donghong, "DH") were sensitive to waterlogging, thus, waterlogging resistant rootstocks (e.g. Actinidia valvata Dunn, "Dunn") were widely used for kiwifruit industry. Those different species provided ideal materials to understand the waterlogging responses in kiwifruit. Compared to the weaken growth and root activities in "DH", "Dunn" maintained the relative high root activities under the prolonged waterlogging. Based on comparative analysis, transcript levels of pyruvate decarboxylase (PDCs) and alcohol dehydrogenase (ADHs) showed significantly difference between these two species. Both PDCs and ADHs had been significantly increased by waterlogging in "DH", while they were only limitedly triggered by 2 days stress and subsided during the prolonged waterlogging in "Dunn". Thus, 19 differentially expressed transcript factors (DETFs) had been isolated using weighted gene co-expression network analysis combined with transcriptomics and transcript levels of PDCs and ADHs in waterlogged "DH". Among these DETFs, dual luciferase and electrophoretic mobility shift assays indicated AcMYB68 could bind to and trigger the activity of AcPDC2 promoter. The stable over-expression of AcMYB68 significantly up-regulated the transcript levels of PDCs but inhibited the plant growth, especially the roots. Moreover, the enzyme activities of PDC in 35S::AcMYB68 were significantly enhanced during the waterlogging response than that in wild type plants. Most interestingly, comparative analysis indicated that the expression patterns of AcMYB68 and the previously characterized AcERF74/75 (the direct regulator on ADHs) either showed no responses (AcMYB68 and AcERF74) or very limited response (AcERF75) in "Dunn". Taken together, the restricted responses of AcMYB68 and AcERF74/75 in "Dunn" endow its waterlogging tolerance.


Asunto(s)
Actinidia , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Piruvato Descarboxilasa , Actinidia/genética , Actinidia/fisiología , Actinidia/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Piruvato Descarboxilasa/genética , Piruvato Descarboxilasa/metabolismo , Alcohol Deshidrogenasa/genética , Alcohol Deshidrogenasa/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/fisiología , Agua/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Estrés Fisiológico , Regiones Promotoras Genéticas/genética
3.
Plant Physiol ; 195(1): 598-616, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38319742

RESUMEN

Chinese bayberry (Morella rubra) is a fruit tree with a remarkable variation in fruit color, ranging from white to dark red as determined by anthocyanin content. In dark red "Biqi" (BQ), red "Dongkui" (DK), pink "Fenhong" (FH), and white "Shuijing" (SJ), we identified an anthocyanin-related MYB transcription factor-encoding gene cluster of four members, i.e. MrMYB1.1, MrMYB1.2, MrMYB1.3, and MrMYB2. Collinear analysis revealed that the MYB tandem cluster may have occurred in a highly conserved region of many eudicot genomes. Two alleles of MrMYB1.1 were observed; MrMYB1.1-1 (MrMYB1.1n) was a full-length allele and homozygous in "BQ", MrMYB1.1-2 (MrMYB1.1d) was a nonfunctional allele with a single base deletion and homozygous in "SJ", and MrMYB1.1n/MrMYB1.1d were heterozygous in "DK" and "FH". In these four cultivars, expression of MrMYB1.1, MrMYB1.2, and MrMYB2 was enhanced during ripening. Both alleles were equally expressed in MrMYB1.1n/MrMYB1.1d heterozygous cultivars as revealed by a cleaved amplified polymorphic sequence marker. Expression of MrMYB1.3 was restricted to some dark red cultivars only. Functional characterization revealed that MrMYB1.1n and MrMYB1.3 can induce anthocyanin accumulation while MrMYB1.1d, MrMYB1.2, and MrMYB2 cannot. DNA-protein interaction assays indicated that MrMYB1.1n and MrMYB1.3 can directly bind to and activate the promoters of anthocyanin-related genes via interaction with a MYC-like basic helix-loop-helix protein MrbHLH1. We concluded that the specific genotype of MrMYB1.1 alleles, as well as the exclusive expression of MrMYB1.3 in some dark red cultivars, contributes to fruit color variation. The study provides insights into the mechanisms for regulation of plant anthocyanin accumulation by MYB tandem clusters.


Asunto(s)
Frutas , Regulación de la Expresión Génica de las Plantas , Familia de Multigenes , Pigmentación , Proteínas de Plantas , Factores de Transcripción , Frutas/genética , Frutas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pigmentación/genética , Antocianinas/metabolismo , Filogenia , Alelos , Genes de Plantas , Datos de Secuencia Molecular , Secuencia de Aminoácidos , Color
4.
Plant Physiol ; 193(1): 840-854, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37325946

RESUMEN

As the harvest season of most fruit is concentrated, fruit maturation manipulation is essential for the fresh fruit industry to prolong sales time. Gibberellin (GA), an important phytohormone necessary for plant growth and development, has also shown a substantial regulatory effect on fruit maturation; however, its regulatory mechanisms remain inconclusive. In this research, preharvest GA3 treatment effectively delayed fruit maturation in several persimmon (Diospyros kaki) cultivars. Among the proteins encoded by differentially expressed genes, 2 transcriptional activators (NAC TRANSCRIPTION FACTOR DkNAC24 and ETHYLENE RESPONSIVE FACTOR DkERF38) and a repressor (MYB-LIKE TRANSCRIPTION FACTOR DkMYB22) were direct regulators of GERANYLGERANYL DIPHOSPHATE SYNTHASE DkGGPS1, LYSINE HISTIDINE TRANSPORTER DkLHT1, and FRUCTOSE-BISPHOSPHATE ALDOLASE DkFBA1, respectively, resulting in the inhibition of carotenoid synthesis, outward transport of an ethylene precursor, and consumption of fructose and glucose. Thus, the present study not only provides a practical method to prolong the persimmon fruit maturation period in various cultivars but also provides insights into the regulatory mechanisms of GA on multiple aspects of fruit quality formation at the transcriptional regulation level.


Asunto(s)
Diospyros , Giberelinas , Giberelinas/farmacología , Giberelinas/metabolismo , Diospyros/genética , Diospyros/metabolismo , Frutas/metabolismo , Etilenos/metabolismo , Factores de Transcripción/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
5.
J Exp Bot ; 75(1): 204-218, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37712824

RESUMEN

The degradation of chlorophyll during fruit development is essential to reveal a more 'ripe' color that signals readiness to wild dispersers of seeds and the human consumer. Here, comparative biochemical analysis of developing fruit of Actinidia deliciosa cv. Xuxiang ('XX', green-fleshed) and Actinidia chinensis cv. Jinshi No.1 ('JS', yellow-fleshed) indicated that variation in chlorophyll content is the major contributor to differences in flesh color. Four differentially expressed candidate genes were identified: the down-regulated genes AcCRD1 and AcPOR1 involved in chlorophyll biosynthesis, and the up-regulated genes AcSGR1 and AcSGR2 driving chlorophyll degradation. Prochlorophyllide and chlorophyllide, the metabolites produced by AcCRD1 and AcPOR1, progressively reduced in 'JS', but not in 'XX', indicating that chlorophyll biosynthesis was less active in yellow-fleshed fruit. AcSGR1 and AcSGR2 were verified to be involved in chlorophyll degradation, using both transient expression in tobacco and stable overexpression in kiwifruit. Furthermore, a homeobox-leucine zipper (HD-Zip II), AcHZP45, showed significantly increased expression during 'JS' fruit ripening, which led to both repressed expression of AcCRD1 and AcPOR1 and activated expression of AcSGR1 and AcSGR2. Collectively, the present study indicated that different dynamics of chlorophyll biosynthesis and degradation coordinate the changes in chlorophyll content in kiwifruit flesh, which are orchestrated by the key transcription factor AcHZP45.


Asunto(s)
Actinidia , Humanos , Actinidia/genética , Clorofila/metabolismo , Frutas/genética , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas
6.
Artículo en Inglés | MEDLINE | ID: mdl-38970691

RESUMEN

To evaluate the in vitro activity of ampicillin-sulbactam and cefoperazone-sulbactam against A. baumannii using the broth disk elution testing, a total of 150 A. baumannii isolates were collected from across China between January 2019 and January 2021, including 51 carbapenem-susceptible and 99 carbapenem-resistant isolates. Broth disk elution (BDE) and the broth microdilution (BMD) method were performed for all strains. The concentration range of the BDE was 10/10 µg/mL, 20/20 µg/mL, and 30/30 µg/mL for ampicillin-sulbactam, and 37.5/15 µg/mL, 75/30 µg/mL, 112.5/45 µg/mL, and 150/60 µg/mL for cefoperazone-sulbactam, respectively. Compared with BMD, the BDE results of ampicillin-sulbactam and cefoperazone-sulbactam showed a categorical agreement of 83.3% (125/150) and 95.3% (143/150), with minor errors of 16.7% (25/150) and 4.7% (7/150), respectively. No major error or very major errors were detected. The sensitivity differences by BDE of carbapenem-resistant A. baumannii (CRAb) to different concentrations of ampicillin-sulbactam showed statistically significant (p < 0.017), while those to cefoperazone-sulbactam at 37.5/15 µg/mL, 75/30 µg/mL, and 112.5/45 µg/mL were significant (p < 0.008). However, no significant difference in sensitivity was observed between 112.5/45 µg/mL and 150/60 µg/mL (p > 0.008). In conclusion, the BDE is a reliable and convenient method to detect the in vitro activity of cefoperazone-sulbactam against A. baumannii, and the results could serve as a clinical reference value when deciding whether or not to use high-dose sulbactam for the treatment of A. baumannii infections.

7.
Plant Biotechnol J ; 21(8): 1695-1706, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37161940

RESUMEN

Citrate is a common primary metabolite which often characterizes fruit flavour. The key regulators of citrate accumulation in fruit and vegetables are poorly understood. We systematically analysed the dynamic profiles of organic acid components during the development of kiwifruit (Actinidia spp.). Citrate continuously accumulated so that it became the predominate contributor to total acidity at harvest. Based on a co-expression network analysis using different kiwifruit cultivars, an Al-ACTIVATED MALATE TRANSPORTER gene (AcALMT1) was identified as a candidate responsible for citrate accumulation. Electrophysiological assays using expression of this gene in Xenopus oocytes revealed that AcALMT1 functions as a citrate transporter. Additionally, transient overexpression of AcALMT1 in kiwifruit significantly increased citrate content, while tissues showing higher AcALMT1 expression accumulated more citrate. The expression of AcALMT1 was highly correlated with 17 transcription factor candidates. However, dual-luciferase and EMSA assays indicated that only the NAC transcription factor, AcNAC1, activated AcALMT1 expression via direct binding to its promoter. Targeted CRISPR-Cas9-induced mutagenesis of AcNAC1 in kiwifruit resulted in dramatic declines in citrate levels while malate and quinate levels were not substantially affected. Our findings show that transcriptional regulation of a major citrate transporter, by a NAC transcription factor, is responsible for citrate accumulation in kiwifruit, which has broad implications for other fruits and vegetables.


Asunto(s)
Ácido Cítrico , Factores de Transcripción , Ácido Cítrico/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Frutas/metabolismo , Malatos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas/genética
8.
PLoS Biol ; 17(4): e3000096, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-31009446

RESUMEN

The Orai channel is characterized by voltage independence, low conductance, and high Ca2+ selectivity and plays an important role in Ca2+ influx through the plasma membrane (PM). How the channel is activated and promotes Ca2+ permeation is not well understood. Here, we report the crystal structure and cryo-electron microscopy (cryo-EM) reconstruction of a Drosophila melanogaster Orai (dOrai) mutant (P288L) channel that is constitutively active according to electrophysiology. The open state of the Orai channel showed a hexameric assembly in which 6 transmembrane 1 (TM1) helices in the center form the ion-conducting pore, and 6 TM4 helices in the periphery form extended long helices. Orai channel activation requires conformational transduction from TM4 to TM1 and eventually causes the basic section of TM1 to twist outward. The wider pore on the cytosolic side aggregates anions to increase the potential gradient across the membrane and thus facilitate Ca2+ permeation. The open-state structure of the Orai channel offers insights into channel assembly, channel activation, and Ca2+ permeation.


Asunto(s)
Canales de Calcio/metabolismo , Calcio/metabolismo , Proteínas de Drosophila/metabolismo , Proteína ORAI1/metabolismo , Animales , Calcio/fisiología , Membrana Celular/metabolismo , Microscopía por Crioelectrón , Proteínas de Drosophila/genética , Drosophila melanogaster/metabolismo , Activación del Canal Iónico/fisiología , Proteínas de la Membrana/metabolismo , Proteína ORAI1/genética , Estructura Secundaria de Proteína
9.
Molecules ; 27(3)2022 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-35164349

RESUMEN

Polymyxin-based combination therapy is commonly used to treat carbapenem-resistant Acinetobacter baumannii (CRAB) infections. In the present study, the bactericidal effect of polymyxin B and minocycline combination was tested in three CRAB strains containing blaOXA-23 by the checkerboard assay and in vitro dynamic pharmacokinetics/pharmacodynamics (PK/PD) model. The combination showed synergistic or partial synergistic effect (fractional inhibitory concentration index ≤0.56) on the tested strains in checkboard assays. The antibacterial activity was enhanced in the combination group compared with either monotherapy in in vitro PK/PD model. The combination regimen (simultaneous infusion of 0.75 mg/kg polymyxin B and 100 mg minocycline via 2 h infusion) reduced bacterial colony counts by 0.9-3.5 log10 colony forming units per milliliter (CFU/mL) compared with either drug alone at 24 h. In conclusion, 0.75 mg/kg polymyxin B combined with 100 mg minocycline via 2 h infusion could be a promising treatment option for CRAB bloodstream infections.


Asunto(s)
Infecciones por Acinetobacter/tratamiento farmacológico , Acinetobacter baumannii/efectos de los fármacos , Antibacterianos/farmacología , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Sinergismo Farmacológico , Minociclina/farmacología , Polimixina B/farmacología , Infecciones por Acinetobacter/microbiología , Antibacterianos/farmacocinética , Carbapenémicos/farmacología , Quimioterapia Combinada , Técnicas In Vitro , Minociclina/farmacocinética , Polimixina B/farmacocinética , Distribución Tisular , beta-Lactamasas/genética
10.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(4): 382-386, 2022 Apr 15.
Artículo en Zh | MEDLINE | ID: mdl-35527412

RESUMEN

OBJECTIVES: To study the etiology and clinical features of children with ascites, so as to provide a basis for the diagnosis and treatment of ascites in children. METHODS: The medical data of the children with ascites, who were hospitalized from January 1, 2010 to December 31, 2019, were retrospectively reviewed. RESULTS: Among the 165 children with ascites, the male/female ratio was 1.53:1, and the mean age of onset was (6±4) years. The causes of ascites included surgical acute abdomen (39 children, 23.6%), infectious diseases (39 children, 23.6%), neoplastic diseases (27 children, 16.4%), hepatogenic diseases (18 children, 10.9%), pancreatitis (10 children, 6.1%), cardiogenic diseases (8 children, 4.8%), rheumatic immune diseases (6 children, 3.6%), and nephrogenic diseases (5 children, 3.0%). According to the age of onset, there were 33 infants, 24 young children, 30 preschool children, 41 school-aged children, and 37 adolescents. Surgical acute abdomen and hepatogenic diseases were the main causes of ascites in infants (P<0.05). Neoplastic disease was the leading cause in young children (P<0.05). Infectious diseases were the most common cause in adolescents (P<0.05). CONCLUSIONS: Surgical acute abdomen, infectious diseases, neoplastic diseases, and hepatogenic diseases are the common causes of ascites in children, and there are some differences in the leading cause of ascites between different age groups.


Asunto(s)
Abdomen Agudo , Enfermedades Transmisibles , Neoplasias , Pancreatitis , Abdomen Agudo/complicaciones , Adolescente , Ascitis/etiología , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Neoplasias/complicaciones , Pancreatitis/complicaciones , Estudios Retrospectivos
11.
BMC Genomics ; 22(1): 530, 2021 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-34247587

RESUMEN

BACKGROUND: Acinetobacter baumannii is a common nosocomial pathogen that poses a huge threat to global health. Owing to the severity of A. baumannii infections, it became necessary to investigate the epidemiological characteristics of A. baumannii in Chinese hospitals and find the reasons for the high antibiotic resistance rate and mortality. This study aimed to investigate the epidemiologic and genetic characteristics of A. baumannii isolated from patients with hospital acquired pneumonia (HAP), bloodstream infection (BSI) and urinary tract infection (UTI) in China and uncover potential mechanisms for multi-drug resistance and virulence characteristics of A. baumannii isolates. RESULTS: All isolates were classified into two primary clades in core gene-based phylogenetic relationship. Clonal complex 208 (CC208) mainly consisted of ST195 (32 %) and ST208 (24.6 %). CC208 and non-CC208 isolates had carbapenem resistance rates of 96.2 and 9.1 %, respectively. Core genes were enriched in 'Amino acid transport and metabolism', 'Translation', 'Energy production and conversion', 'Transcription', 'Inorganic ion transport and metabolism' and 'Cell wall/membrane/envelope synthesis'. Most isolates possessed virulence factors related to polysaccharide biosynthesis, capsular polysaccharide synthesis and motility. Eleven isolates belong to ST369 or ST191 (oxford scheme) all had the virulence factor cap8E and it had a higher positive rate in UTI (35.3 %) than in BSI (18.9 %) and HAP (12.9 %). ABGRI1 antibiotic resistance islands were responsible for streptomycin, tetracycline and sulfonate resistance. The blaOXA-23 gene was the most probable cause for carbapenem resistance, although the blaOXA-66 gene with nonsynonymous SNPs (F82L, I129L) was not. CONCLUSIONS: A. baumannii is a genomically variable pathogen that has the potential to cause a range of infectious diseases. There is high proportion of carbapenem resistance in isolates from all three infection sites (HAP, BSI and UTI), which can be attributed to the blaOXA-23 gene. CC208 is the predominant clone in blaOXA-23-carrying A. baumannii that should be monitored. Virulence factors involving bacteria motility and polysaccharide biosynthesis which are widespread in clinical A. baumannii strains deserve our attention.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Enfermedades Transmisibles , Infecciones por Acinetobacter/epidemiología , Acinetobacter baumannii/genética , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Carbapenémicos/farmacología , China/epidemiología , Farmacorresistencia Bacteriana Múltiple , Genómica , Humanos , Pruebas de Sensibilidad Microbiana , Filogenia , beta-Lactamasas/genética
12.
New Phytol ; 232(1): 237-251, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34137052

RESUMEN

Ethylene plays an important role in regulating fruit ripening by triggering dynamic changes in expression of ripening-associated genes, but the functions of many of these genes are still unknown. Here, a methionine sulfoxide reductase gene (AdMsrB1) was identified by transcriptomics-based analysis as the gene most responsive to ethylene treatment in ripening kiwifruit. The AdMsrB1 protein exhibits a stereospecific activity toward the oxidative stress-induced R enantiomer of methionine sulfoxide (MetSO), reducing it to methionine (Met). Stable overexpression of AdMsrB1 in kiwifruit significantly increased the content of free Met and 1-aminocyclopropane-1-carboxylic acid (ACC), the immediate precursor of ethylene, and increased ethylene production. Dual-luciferase assays indicated that the AdMsrB1 promoter was not directly upregulated by ethylene treatment but was modulated by two ethylene-inducible NAM/ATAF/CUC transcription factors (AdNAC2 and AdNAC72) that bind directly to the AdMsrB1 promoter. Overexpression of AdNAC72 in kiwifruit not only enhanced AdMsrB1 expression, but also increased free Met and ACC content and ethylene production rates. This finding establishes an unexpected regulatory loop that enhances ethylene production and the concentration of its biosynthetic intermediates.


Asunto(s)
Frutas , Factores de Transcripción , Etilenos , Frutas/genética , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas , Metionina , Metionina Sulfóxido Reductasas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
13.
Br J Clin Pharmacol ; 87(12): 4636-4647, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33928669

RESUMEN

AIMS: To optimize the dosing regimen in patients with severe renal impairment based on population pharmacokinetic (PPK)/pharmacodynamic analysis. METHODS: The pharmacokinetics and safety of nemonoxacin was evaluated in a single-dose, open-label, nonrandomized, parallel-group study after single oral dose of a 0.5-g nemonoxacin capsule in 10 patients with severe renal impairment and 10 healthy controls. Both blood and urine samples were collected within 72 hours after admission and determined the concentrations. A PPK model was built using nonlinear mixed effects modelling. The probability of target attainment and the cumulative fraction of response against Streptococcus pneumoniae and Staphylococcus aureus was calculated by Monte Carlo simulation. RESULTS: The data best fitted a 2-compartment model, from which the PPK parameters were estimated, including clearance (8.55 L/h), central compartment volume (80.8 L) and peripheral compartment volume (50.6 L). The accumulative urinary excretion was 23.4 ± 6.5% in severe renal impairment patients and 66.1 ± 16.8% in healthy controls. PPK/pharmacodynamic modelling and simulation of 4 dosage regimens found that nemonoxacin 0.5 g every 48 hours (q48h) was the optimal dosing regimen in severe renal impairment patients, evidenced by higher probability of target attainment (92.7%) and cumulative fraction of response (>99%) at nemonoxacin minimum inhibitory concentration ≤ 1 mg/L against S. pneumoniae and S. aureus. The alternative regimens (0.25 g q24h; loading dose 0.5 g on Day 1 followed by 0.25 g q24h) were insufficient to cover the pathogens even if minimum inhibitory concentration = 1 mg/L. CONCLUSION: An extended dosing interval (0.5 g q48h) may be appropriate for optimal efficacy of nemonoxacin in case of severe renal impairment.


Asunto(s)
Quinolonas , Staphylococcus aureus , Antibacterianos , Humanos , Pruebas de Sensibilidad Microbiana , Método de Montecarlo
14.
Pharm Res ; 38(1): 79-87, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33496870

RESUMEN

PURPOSES: To evaluate the effects of component contents in different colistin methanesulfonate (CMS) formulas on their clinical pharmacokinetics of the prodrug CMS and the formed colistin. METHODS: Two CMS formulas (CTTQ and Parkedale) were investigated in a single dose, randomized, open-label, crossover study conducted in 18 healthy Chinese subjects. Both CMS formulas met the requirements of European Pharmacopoeia 9.2 with 12.1% difference in the two major active components (CMS A and CMS B). The PK parameters after a single intravenous infusion of CMS at 2.5 mg/kg were calculated and the steady-state plasma colistin concentrations (Css,avg) following multiple dosing, once every 12 h for 7 days, were simulated with the non-compartment model. RESULTS: The systemic exposure (AUC0-inf) of CMS were 59.49 ± 5.90 h·µg/mL and 51.09 ± 4.70 h·µg/mL, and the AUC0-inf of colistin were 15.39 ± 2.63 h·µg/mL and 12.36 ± 2.10 h·µg/mL for CTTQ and Parkedale, respectively. The ratios (90% CI) of geometric mean of AUC0-inf of CTTQ to Parkedale were 116.38% (112.95%, 119.91%) and 124.49% (120.76%, 128.35%) for CMS and colistin, respectively. The predicted Css,avg (95% CI) were 0.92 (0.85, 0.99) µg/mL and 0.74 (0.69, 0.79) µg/mL for CTTQ and Parkedale, respectively. CONCLUSION: The difference in component content in the two CMS formulas had a significant (P < 0.001) impact on the systemic exposure of colistin in human, thus, warranted essential considerations in clinical applications.


Asunto(s)
Antibacterianos/farmacocinética , Colistina/farmacocinética , Adulto , Antibacterianos/administración & dosificación , Antibacterianos/química , Colistina/administración & dosificación , Colistina/química , Estudios Cruzados , Composición de Medicamentos/métodos , Femenino , Voluntarios Sanos , Humanos , Infusiones Intravenosas , Masculino , Profármacos/administración & dosificación , Profármacos/química , Profármacos/farmacocinética , Adulto Joven
15.
J Pharmacol Sci ; 145(1): 115-121, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33357769

RESUMEN

As a natural compound isolated from Paeoniae radix, Paeoniflorin (PF) has been shown the antitumor effects in various types of human cancers including glioma, which is one of the serious tumors in central nervous system. Translocator protein 18 KDa (TSPO) has been shown to be relevant to the glioma aetiology. However, the regulation of PF in TSPO and neurosteriods biosynthesis on glioma is still unclear. In the present study, the glioma cell (U87 and U251) were cultured and used to quantify the bindings of PF on TSPO. Results indicated that there was not significant different between IC50 of PF and TSPO ligand PK11195. Moreover, PF exerted the anti-proliferative effects in glioma cell with a dose dependent inhibition from 12.5 to 100 µM in vitro. Consistent with the effects of PK11195, lowered levels on progesterone, allopregnanolone, as well as TSPO mRNA were induced by PF (25 and 50 µM). Furthermore, a xenograft mouse model with U87 cell-derived was significant inhibited by PF treatment, as well as the PK11195 administration. These results demonstrate that PF exerts its antitumor effects associated with the TSPO and neurosteroids biosynthesis in glioma cells could be a promising therapeutic agent for glioma therapy.


Asunto(s)
Antineoplásicos Fitogénicos , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Glioma/tratamiento farmacológico , Glioma/genética , Glucósidos/farmacología , Glucósidos/uso terapéutico , Monoterpenos/farmacología , Monoterpenos/uso terapéutico , Fitoterapia , Receptores de GABA/metabolismo , Animales , Línea Celular Tumoral , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Glioma/metabolismo , Glioma/patología , Isoquinolinas/farmacología , Isoquinolinas/uso terapéutico , Neuroesteroides/metabolismo
16.
Eur J Nutr ; 60(4): 2155-2168, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33068158

RESUMEN

PURPOSE: Genistein (GEN) has been reported to have diverse biological activities, including antioxidant, hypolipidemic, and antidiabetic effects. This study investigated whether the ameliorative effects of GEN on inflammation and insulin resistance were associated with the modulation of gut microbiota composition in type 2 diabetic (T2D) mice. METHODS: C57BL/6J mice were treated with a high-fat diet/streptozotocin to induce T2D and then gavaged with GEN (20 and 40 mg/kg) for 8 weeks. Then, oral glucose tolerance, fasting blood glucose, serum insulin, glucagon, lipid profiles, and pro-inflammatory factors were measured. After this, hepatic function and histopathological analysis and inflammation-related indices of the liver and colon were determined, along with short-chain fatty acid (SCFA) and gut microbiota composition. RESULTS: GEN treatment decreased hyperglycemia, hyperlipidemia, and serum pro-inflammatory factor levels and attenuated hepatic dysfunction, pathological changes, inflammation-related protein expression, and hepatocyte apoptosis. It also ameliorated colonic pathological changes, tight junction-associated protein expression, and pro-inflammatory factor increases. Furthermore, high-dose GEN treatment increased the concentrations of SCFAs and down-regulated the ratio of Firmicutes/Bacteroidetes and the abundance of Proteobacteria at the phylum level. However, GEN increased the abundances of Bacteroides and Prevotella and decreased the levels of Helicobacter and Ruminococcus at the genus level in T2D mice. CONCLUSION: GEN showed ameliorative effects on glucose and lipid dysmetabolism and hepatic and colonic dysfunction; most importantly, GEN could ameliorate inflammation and insulin resistance through modulation of gut microbiota composition.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Resistencia a la Insulina , Animales , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Dieta Alta en Grasa/efectos adversos , Genisteína , Inflamación/tratamiento farmacológico , Ratones , Ratones Endogámicos C57BL
17.
Med Sci Monit ; 27: e930197, 2021 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-34426568

RESUMEN

BACKGROUND The goal of this study was to investigate different doses of nalbuphine combined with dexmedetomidine in the postoperative treatment of laparoscopic oophorocystectomy. MATERIAL AND METHODS This prospective single-blinded randomized controlled study included 219 patients with benign ovarian cysts who received laparoscopic oophorocystectomy from March 2017 to October 2019. Patients were randomized into 4 groups: low (0.5 mg/kg), middle (1.0 mg/kg), and high (1.5 mg/kg) doses of nalbuphine combined with dexmedetomidine (4 µg/kg) (LND, MND, and HND groups, respectively) and a control group with sufentanil (2.5 µg/kg), with different patient-controlled intravenous analgesia pump (PCIA) strategies. Rest and active visual analog scale (VAS) scores measured postoperative pain, and Ramsay scores were used to measure sedation. RESULTS The HND group showed the lowest rest and cough VAS scores at 2 h, 8 h, 12 h, and 24 h after surgery, the lowest PCIA pressing time within 48 h after surgery, and the highest Ramsay scores at 2 h, 8 h, 24 h and 48 h after surgery. Rest and cough VAS scores decreased with higher nalbuphine doses in a dose-dependent manner. One day after surgery, IL-1ß and IL-6 levels increased in all groups, with the lowest levels of IL-1ß and IL-6 in the HND group. Hospitalization time was significantly shorter in the HND group compared with the LND and MND groups. There were no significant differences in complications among groups. CONCLUSIONS Combined nalbuphine and dexmedetomidine improved postoperative pain and sedative conditions, reduced inflammation in a nalbuphine dose-dependent manner, and might facilitate patient recovery.


Asunto(s)
Analgésicos/administración & dosificación , Dexmedetomidina/administración & dosificación , Laparoscopía , Nalbufina/administración & dosificación , Ovariectomía , Dolor Postoperatorio/tratamiento farmacológico , Adulto , Biomarcadores/sangre , Toma de Decisiones Clínicas , Manejo de la Enfermedad , Femenino , Hospitalización , Humanos , Laparoscopía/efectos adversos , Laparoscopía/métodos , Persona de Mediana Edad , Ovariectomía/efectos adversos , Ovariectomía/métodos , Manejo del Dolor , Dimensión del Dolor , Dolor Postoperatorio/diagnóstico , Dolor Postoperatorio/etiología , Resultado del Tratamiento
18.
Int J Mol Sci ; 22(23)2021 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-34884575

RESUMEN

'Jimba' is a white chrysanthemum cultivar, which occasionally and spontaneously produces red flower petals under natural cultivation due to cyanidin-based anthocyanin accumulation. To investigate the underlying mechanism of this process, a comparative transcriptome was analyzed between white and turning red 'Jimba'. The structural and regulatory genes of anthocyanin pathway were significantly up-regulated in turning red 'Jimba'. Among them, two alternative splicings, CmbHLH2 and CmbHLH2.1, showed the most significantly up-regulated in turning red tissue. Transiently over-expressed 35S::CmMYB6-CmbHLH2 strongly induced anthocyanin accumulation in 'Jimba' flower petals, while moderate amount of anthocyanin was detected when over-expressed 35S::CmMYB6-CmbHLH2.1. Both CmbHLH2 and CmbHLH2.1 could interact with CmMYB6 to activate CmDFR promoter according to Yeast two-hybrid and dual-luciferase assay. Moreover, CmMYB6-CmbHLH2 but not CmMYB6-CmbHLH2.1 could activate the CmbHLH2 promoter to provide positive feedback loop regulation. Taken together, it suggested that both CmbHLH2 and CmbHLH2.1 involved in regulation flower color alteration in turning red 'Jimba', and CmbHLH2 played a predominant role in this process.


Asunto(s)
Empalme Alternativo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Chrysanthemum/fisiología , Color , Flores/fisiología , Proteínas de Plantas/metabolismo , Transcriptoma , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética
19.
BMC Plant Biol ; 20(1): 103, 2020 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-32138665

RESUMEN

BACKGROUND: Aroma is an important organoleptic quality for fruit and has a large influence on consumer preference. Kiwifruit esters undergo rapid and substantial changes contributing to the flavor during fruit ripening. Part of enzymes and their coding genes have been indicated potential candidates for flavor-related esters synthesis. However, there still exist obvious gaps in the biosynthetic pathways of esters and the mechanisms regulating ester biosynthesis in kiwifruit remain unknown. RESULTS: Using gas chromatography-mass spectrometry (GC-MS), volatile compounds of kiwifruit were quantified in response to ethylene (ETH, 100 µl/l, 24 h, 20 °C) and 1-methylcyclopropene (1-MCP, 1 µl/l, 24 h, 20 °C). The results indicated that esters showed the most substantial changes enhanced by ethylene and were inhibited by 1-MCP. Correlations between RNA-seq results and concentrations of esters, constructed using Weighted Gene Co-Expression Network Analysis (WGCNA) indicated that three structural genes (fatty acid desaturase, AdFAD1; aldehyde dehydrogenase, AdALDH2; alcohol acyltransferase, AdAT17) had similar expression patterns that paralled the changes in total ester content, and AdFAD1 transcripts exhibited the highest correlation. In order to search for potential regulators for ester biosynthesis, 14 previously reported ethylene-responsive transcription factors (TFs) were included in the correlation analysis with esters and their biosynthetic genes. Using dual-luciferase assay, the in vivo regulatory activities of TFs on ester biosynthetic gene promoters were investigated and the results indicated that AdNAC5 and AdDof4 (DNA binding with one finger) trans-activated and trans-suppressed the AdFAD1 promoter. CONCLUSIONS: The present study advanced the molecular basis of ripening-related ester biosynthesis in kiwifruit by identifying three biosynthetic related genes AdFAD1, AdALDH2 and AdAT17 by transcriptome analysis, and highlighted the function of two TFs by transactivation studies.


Asunto(s)
Actinidia/genética , Ésteres/metabolismo , Frutas/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Transcriptoma , Actinidia/metabolismo , Frutas/genética , Frutas/metabolismo , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Proteínas de Plantas/metabolismo
20.
Plant Biotechnol J ; 18(11): 2267-2279, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32216018

RESUMEN

The RAV (related to ABI3/viviparous 1) group of transcription factors (TFs) play multifaceted roles in plant development and stress responses. Here, we show that strawberry (Fragaria × ananassa) FaRAV1 positively regulates anthocyanin accumulation during fruit ripening via a hierarchy of activation processes. Dual-luciferase assay screening of all fruit-expressed AP2/ERFs showed FaRAV1 had the highest transcriptional activation of the promoter of FaMYB10, a key activator of anthocyanin biosynthesis. Yeast one-hybrid and electrophoretic mobility shift assays indicated that FaRAV1 could directly bind to the promoter of FaMYB10. Transient overexpression of FaRAV1 in strawberry fruit increased FaMYB10 expression and anthocyanin production significantly. Correspondingly, transient RNA interference-induced silencing of FaRAV1 led to decreases in FaMYB10 expression and anthocyanin content. Transcriptome analysis of FaRAV1-overexpressing strawberry fruit revealed that transcripts of phenylpropanoid and flavonoid biosynthesis pathway genes were up-regulated. Luciferase assays showed that FaRAV1 could also activate the promoters of strawberry anthocyanin biosynthetic genes directly, revealing a second level of FaRAV1 action in promoting anthocyanin accumulation. These results show that FaRAV1 stimulates anthocyanin accumulation in strawberry both by direct activation of anthocyanin pathway gene promoters and by up-regulation of FaMYB10, which also positively regulates these genes.


Asunto(s)
Fragaria , Antocianinas , Fragaria/genética , Fragaria/metabolismo , Frutas/genética , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
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