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1.
Planta ; 259(5): 104, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38551672

RESUMEN

MAIN CONCLUSION: The post-transcriptional gene regulatory pathway and small RNA pathway play important roles in regulating the rapid and long-term response of Rhododendron moulmainense to high-temperature stress. The Rhododendron plays an important role in maintaining ecological balance. However, it is difficult to domesticate for use in urban ecosystems due to their strict optimum growth temperature condition, and its evolution and adaptation are little known. Here, we combined transcriptome and small RNAome to reveal the rapid response and long-term adaptability regulation strategies in Rhododendron moulmainense under high-temperature stress. The post-transcriptional gene regulatory pathway plays important roles in stress response, in which the protein folding pathway is rapidly induced at 4 h after heat stress, and alternative splicing plays an important role in regulating gene expression at 7 days after heat stress. The chloroplasts oxidative damage is the main factor inhibiting photosynthesis efficiency. Through WGCNA analysis, we identified gene association patterns and potential key regulatory genes responsible for maintaining the ROS steady-state under heat stress. Finally, we found that the sRNA synthesis pathway is induced under heat stress. Combined with small RNAome, we found that more miRNAs are significantly changed under long-term heat stress. Furthermore, MYBs might play a central role in target gene interaction network of differentially expressed miRNAs in R. moulmainense under heat stress. MYBs are closely related to ABA, consistently, ABA synthesis and signaling pathways are significantly inhibited, and the change in stomatal aperture is not obvious under heat stress. Taken together, we gained valuable insights into the transplantation and long-term conservation domestication of Rhododendron, and provide genetic resources for genetic modification and molecular breeding to improve heat resistance in Rhododendron.


Asunto(s)
MicroARNs , Rhododendron , Transcriptoma/genética , Rhododendron/genética , Rhododendron/metabolismo , Ecosistema , Respuesta al Choque Térmico/genética , MicroARNs/genética , Perfilación de la Expresión Génica
2.
J Org Chem ; 89(1): 710-718, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38101332

RESUMEN

The proton of alcohols as the sole hydrogen source in diboron-mediated nickel-catalyzed asymmetric transfer hydrogenation of cyclic N-sulfonyl imines has been developed, providing the chiral cyclic sulfamidates in excellent enantioselectivities. The mechanistic investigations suggested that the proton of alcohols could be activated by tetrahydroxydiboron to form active nickel hydride species.

3.
J Org Chem ; 87(15): 10398-10407, 2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-35867907

RESUMEN

A palladium-catalyzed asymmetric hydrogenation of unprotected 3-substituted indoles was developed, providing a series of 3-substituted indolines in excellent yields with ≤94.4:5.6 er. The large sterically hindered bisphosphine ligand played a crucial role in the enantioselective control. In addition, the gram-scale hydrogenation experiment and product derivatizations were performed successfully.

4.
Arch Gynecol Obstet ; 305(4): 837-850, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34498124

RESUMEN

BACKGROUND: Our current study was performed aimed at determining the efficacy and safety profile of robotic surgery (RS) compared to laparoscopic surgery (LPS) and laparotomy (LT) in the treatment of endometrial cancer on the basis of relevant studies. PATIENTS AND METHODS: A systematic literature search was conducted based on appropriate keywords, using the Embase, Cochrane library, as well as PubMed. Our studiers also reviewed the key pertinent sources among the publications and included associated literatures published by June 2021. Odds ratios (ORs), mean difference (MD), as well as 95% confidence interval (95% CI) for each study were measured for further assessment and synthesis of outcomes. RESULTS: Thirty studies involving a total of 12,025 patients were eventually included in the current meta-analysis. Compared with LPS, RS could significantly decrease the estimated blood loss, the incidence of intraoperative complications, the length of hospital stay, and the rate of conversion, and increased the rate of readmission. Compared with LT, RS significantly decreased the estimated blood loss, blood transfusion volume, the length of hospital stay, the rate of total, intraoperative and postoperative complications, and the rate of readmission and re-operation, and increased the operative time. CONCLUSION: Considering the effects and safety profile of RS in terms of treating endometrial cancer, our study suggest that RS exerts superior outcomes than that of LPS and LT.


Asunto(s)
Neoplasias Endometriales , Laparoscopía , Procedimientos Quirúrgicos Robotizados , Neoplasias Endometriales/etiología , Neoplasias Endometriales/cirugía , Femenino , Humanos , Laparoscopía/efectos adversos , Laparotomía/efectos adversos , Tiempo de Internación , Tempo Operativo , Complicaciones Posoperatorias/etiología , Procedimientos Quirúrgicos Robotizados/efectos adversos
5.
Langmuir ; 31(15): 4566-72, 2015 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-25835084

RESUMEN

Despite the significant progress in developing various synthetic strategies for metal oxide hollow spheres (h-MO), the so-far explored materials are mostly chemically inert metal oxides. Very few attempts have been made for amphoteric metal oxides such as Al2O3 and ZnO due to the difficulties in the control of the dissolution and recrystallization process. Herein, a facile self-template route to the synthesis of amphoteric h-MO with tunable size and shell thickness is developed by targeted etching via an acid-base reaction. With the protection of polyvinylpyrrolidone (PVP) on the surface, the interior of metal oxide solid colloidal spheres (c-MOs) that possess radially divergent structures could be selectively etched with acid/alkali as an etchant, forming h-MO of Al2O3 and ZnO. Our results also show that a wide variety of metal oxide colloidal spheres can be potential self-templates for targeted etching, which paves the way for developing a generalized strategy for the synthesis of various metal oxide hollow spheres.

6.
BMC Public Health ; 15: 415, 2015 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-25903064

RESUMEN

BACKGROUND: Multimorbidity, the co-occurrence of two or more chronic conditions, is common among older adults and is known to be associated with high costs and gaps in quality of care. Population-based estimates of multimorbidity are not readily available, which makes future planning a challenge. We aimed to estimate the population-based prevalence and trends of multimorbidity in Ontario, Canada and to examine patterns in the co-occurrence of chronic conditions. METHODS: This retrospective cohort study includes all Ontarians (aged 0 to 105 years) with at least one of 16 common chronic conditions. Descriptive statistics were used to examine and compare the prevalence of multimorbidity by age and number of conditions in 2003 and 2009. The co-occurrence of chronic conditions among individuals with multimorbidity was also explored. RESULTS: The prevalence of multimorbidity among Ontarians rose from 17.4% in 2003 to 24.3% in 2009, a 40% increase. This increase over time was evident across all age groups. Within individual chronic conditions, multimorbidity rates ranged from 44% to 99%. Remarkably, there were no dominant patterns of co-occurring conditions. CONCLUSION: The high prevalence of multimorbidity and numerous combinations of conditions suggests that single, disease-oriented management programs may be less effective or efficient tools for high quality care compared to person-centered approaches.


Asunto(s)
Enfermedad Crónica/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Comorbilidad , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Ontario/epidemiología , Prevalencia , Estudios Retrospectivos , Factores Socioeconómicos , Adulto Joven
7.
FEMS Microbiol Lett ; 3712024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38378945

RESUMEN

Monascus pigments (MPs) are a kind of natural ingredient fermented by Monascus spp., which contains three types of pigments: red, orange, and yellow ones. Monascus yellow pigments have a restricted yield and cannot meet industrial application. The method and mechanism of CaCl2 improving yellow pigments production by liquid fermentation of Monascus purpureus M8 were studied in order to overcome the low yield of yellow pigments produced by liquid fermentation. Changes in physiological and biochemical indicators explained the effects of CaCl2 on the production of Monascus yellow pigments from solid fermentation. The intracellular yellow pigments, orange pigments, and red pigments increased by 156.08%, 43.76%, and 42.73%, respectively, with 60 g/l CaCl2 addition to culture medium. The amount of red and orange pigments reduced, while the proportion of yellow pigments increased and the relative peak area of intracellular yellow pigments accounted for a dominant 98.2%, according to thin layer chromatography and high performance liquid chromatography analyses. Furthermore, the influence of CaCl2 extended to the modulation of pigments synthesis-related gene expression in M8 strain. This modulation led to a pronounced upregulation in the expression of the yellow pigments synthesis-related gene, mppE, signifying a pivotal role played by CaCl2 in orchestrating the intricate machinery behind yellow pigments biosynthesis.


Asunto(s)
Monascus , Fermentación , Monascus/metabolismo , Cloruro de Calcio/metabolismo , Pigmentos Biológicos
8.
Org Lett ; 26(13): 2535-2539, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38526435

RESUMEN

Using readily available manganese pentacarbonyl bromide as a regeneration catalyst, biomimetic asymmetric reduction of imines including quinoxalinones, benzoxazinones, and benzoxazine has been successfully developed in the presence of transfer catalyst chiral phosphoric acids, providing the chiral amines with high yields and enantioselectivities.

9.
J Fungi (Basel) ; 10(3)2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38535238

RESUMEN

Pinus massoniana Lamb. is an important, common afforestation and timber tree species in China. Species of Pestalotiopsis are well-known pathogens of needle blight. In this study, the five representative strains were isolated from needle blight from needles of Pi. massoniana in Nanjing, Jiangsu, China. Based on multi-locus phylogenetic analyses of the three genomic loci (ITS, TEF1, and TUB2), in conjunction with morphological characteristics, a new species, namely Pestalotiopsis jiangsuensis sp. nov., was described and reported. Pathogenicity tests revealed that the five representative strains of the species described above were pathogenic to Pi. massoniana. The study revealed the diversity of pathogenic species of needle blight on Pi. massoniana. This is the first report of needle blight caused by P. jiangsuensis on Pi. massoniana in China and worldwide. This provides useful information for future research on management strategies of this disease.

10.
J Phys Condens Matter ; 36(25)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38457830

RESUMEN

Present research on TiNiSi-type MnCoSi-based alloys focuses on finding a suitable doping element to effectively reduce the critical magnetic field (µ0Hcri) required to induce a metamagnetic transition. This paper provides a guide to achieve this goal through an experimental investigation of Mn1-xPtxCoSi and MnCo1-xPtxSi alloys. In Mn1-xPtxCoSi, asxincreases,µ0Hcriat room temperature decreases, while in MnCo1-xPtxSi, it increases. This phenomenon can be attributed to the fact that larger Pt atoms prefer Co sites over Mn sites, as predicted by our density-functional theory. Consequently, in Mn1-xPtxCoSi, larger Co atoms are extruded into the Mn atoms chain, increasing the nearest Mn-Mn distance and resulting in a reducedµ0Hcri. This finding suggests that transition-metal atoms with more valence electrons preferably occupy the Co site, while those with fewer valence electrons preferably occupy the Mn site. Adhering to this rule, one can easily obtain a lowµ0Hcriand large magnetostrain under a low magnetic field by selecting a suitable foreign element and chemical formula, as demonstrated by the Mn1-xPtxCoSi alloy.

11.
Behav Brain Res ; 466: 114990, 2024 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-38582411

RESUMEN

Previous studies have shown that alertness is closely related to executive control function, but its impact on components of post-error adjustment is unknown. This study applied the Attentional Networks Test and the Four-choice Flanker task with three response stimulus intervals (RSIs) to explore the correlation between alertness and post-error adjustment. The linear mixed-effects model of alertness and RSI on the post-error processing indicators showed a significant negative correlation between the alertness and post-error slowing (PES) under 200 ms RSI , as well as between alertness and post-error improvement in accuracy (PIA) under both 700 ms RSI and 1200 ms RSI. Participants with lower alertness showed larger post-error slowing in the early stages, while those with higher alertness had smaller PIA in later stages. This study revealed the effects of alertness on different processing components of post-error adjustment. The control strategies utilized by individuals with high and low levels of alertness differed in preparation for performance monitoring. Alertness improved post-error response speed in a task-unspecific manner, but not post-error adaptation.


Asunto(s)
Atención , Función Ejecutiva , Desempeño Psicomotor , Tiempo de Reacción , Humanos , Masculino , Femenino , Atención/fisiología , Adulto Joven , Tiempo de Reacción/fisiología , Función Ejecutiva/fisiología , Adulto , Desempeño Psicomotor/fisiología , Adaptación Psicológica/fisiología
12.
Chem Sci ; 14(20): 5477-5482, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37234894

RESUMEN

The development of a new strategy for the construction of chiral cyclic sulfide-containing multiple stereogenic centers is highly desirable. Herein, by the combination of base-promoted retro-sulfa-Michael addition and palladium-catalyzed asymmetric allenylic alkylation, the streamlined synthesis of chiral thiochromanones containing two central chiralities (including a quaternary stereogenic center) and an axial chirality (allene unit) was successfully realized with up to 98% yield, 49.0 : 1 dr and >99% ee.

13.
ACS Appl Mater Interfaces ; 15(35): 41457-41465, 2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37615533

RESUMEN

Li-CO2 batteries that integrate energy storage with greenhouse gas fixation have received a great deal of attention in the pursuit of carbon neutrality. However, cyclic accumulation of the insulative and insoluble Li2CO3 on the cathode surface severely restrains the battery cyclability, especially under a high depth of discharge/charge. Herein, we design and fabricate a microreactor-type catalyst by embedding Ru nanoparticles into the shells of mesoporous hollow carbon spheres. We show that both the hollow cavity and mesoporous shell are indispensable for concertedly furnishing a high activity to catalyze reversible Li2CO3 formation/decomposition. This unique structure ensures that the Ru sites masked by exterior Li2CO3 deposits during charging can resume the redox process of discharge by working with the prestored electrolyte to establish an inner reaction path. The thus fabricated Li-CO2 batteries demonstrate remarkable cyclability of 1085 cycles under 0.5 Ah g-1 and 326 cycles under 2 Ah g-1 at 1 A g-1, outshining most of the literature reports. This study highlights a smart catalyst design to boost the reversibility and cyclability of Li-CO2 batteries through an "in & out" strategy.

14.
Nat Plants ; 9(10): 1627-1642, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37735254

RESUMEN

Parasitic plants have evolved to be subtly or severely dependent on host plants to complete their life cycle. To provide new insights into the biology of parasitic plants in general, we assembled genomes for members of the sandalwood order Santalales, including a stem hemiparasite (Scurrula) and two highly modified root holoparasites (Balanophora) that possess chimaeric host-parasite tubers. Comprehensive genome comparisons reveal that hemiparasitic Scurrula has experienced a relatively minor degree of gene loss compared with autotrophic plants, consistent with its moderate degree of parasitism. Nonetheless, patterns of gene loss appear to be substantially divergent across distantly related lineages of hemiparasites. In contrast, Balanophora has experienced substantial gene loss for the same sets of genes as an independently evolved holoparasite lineage, the endoparasitic Sapria (Malpighiales), and the two holoparasite lineages experienced convergent contraction of large gene families through loss of paralogues. This unprecedented convergence supports the idea that despite their extreme and strikingly divergent life histories and morphology, the evolution of these and other holoparasitic lineages can be shaped by highly predictable modes of genome reduction. We observe substantial evidence of relaxed selection in retained genes for both hemi- and holoparasitic species. Transcriptome data also document unusual and novel interactions between Balanophora and host plants at the host-parasite tuber interface tissues, with evidence of mRNA exchange, substantial and active hormone exchange and immune responses in parasite and host.


Asunto(s)
Interacciones Huésped-Parásitos , Plantas , Interacciones Huésped-Parásitos/genética , Plantas/genética
15.
Bioresour Bioprocess ; 9(1): 56, 2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38647747

RESUMEN

To mimic the Escherichia coli T7 protein expression system, we developed a facile T7 promoter-based protein expression system in an industrial microorganism Bacillus subtilis. This system has two parts: a new B. subtilis strain SCK22 and a plasmid pHT7. To construct strain SCK22, the T7 RNA polymerase gene was inserted into the chromosome, and several genes, such as two major protease genes, a spore generation-related gene, and a fermentation foam generation-related gene, were knocked out to facilitate good expression in high-density cell fermentation. The gene of a target protein can be subcloned into plasmid pHT7, where the gene of the target protein was under tight control of the T7 promoter with a ribosome binding site (RBS) sequence of B. subtilis (i.e., AAGGAGG). A few recombinant proteins (i.e., green fluorescent protein, α-glucan phosphorylase, inositol monophosphatase, phosphoglucomutase, and 4-α-glucanotransferase) were expressed with approximately 25-40% expression levels relative to the cellular total proteins estimated by SDS-PAGE by using B. subtilis SCK22/pHT7-derived plasmid. A fed-batch high-cell density fermentation was conducted in a 5-L fermenter, producing up to 4.78 g/L inositol monophosphatase. This expression system has a few advantageous features, such as, wide applicability for recombinant proteins, high protein expression level, easy genetic operation, high transformation efficiency, good genetic stability, and suitability for high-cell density fermentation.

16.
ACS Appl Mater Interfaces ; 14(16): 18561-18569, 2022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-35417124

RESUMEN

The high activation barrier and sluggish kinetics of Li2CO3 decomposition impose a severe challenge on the development of a Li-CO2 battery with high Coulombic efficiency. To tackle this issue, herein we devise a novel synthetic tactic by combining electrostatic assembly with in situ polycondensation to obtain a single-atomic Ru catalyst of high density up to ∼5 wt %. When deployed to the CO2 cathode, the catalyst delivered an extraordinary capacity of 44.7 Ah g-1, an ultralow charge/discharge polarization of 0.97 V at 0.1 A g-1 (1.90 V at 2 A g-1), and a long-term cycling stability up to 367 cycles at 1 Ah g-1 (196 cycles at 2 Ah g-1), outshining most of the state-of-the-art CO2 cathode catalysts reported today. Further through extensive in situ and ex situ electroanalytical, spectroscopic, and microscopic characterizations, we attribute the superb battery performance mainly to the highly reversible Li2CO3 formation/decomposition, facilitated by the homogenized and downsized Li2CO3 nucleation and growth on account of the high density single-atomic Ru loading. This work not only offers a facile method to fabricate single-atom catalysts with high mass loading but also sheds light on promoting the reversible Li-CO2 reaction by mediating product morphology.

17.
Zhonghua Gan Zang Bing Za Zhi ; 19(1): 52-4, 2011 Jan.
Artículo en Zh | MEDLINE | ID: mdl-21272460

RESUMEN

To investigate the clinical characteristics of abnormal uterine bleeding (AUB) in nonpregnant hepatic cirrhosis patients and to assess the treatment and curative effects of AUB. A retrospective analysis was conducted on 72 nonpregant AUB patients treated in Ditan Hospital from October 2008 to October 2009. Data were assessed with SPSS 10.0 and the constituent ratio was examined by chi-square tests. 58 out of the 72 nonpregnant AUB patients were climacteric patients (80.56%). Approximately 42.5% and 68.8% (x2=7.189, P = 0.027) of the AUB patients were diagnosed with compensated and decompensated liver cirrhosis, respectively, which presents a statistical significance. Among the 18 cases of AUB with hypermenorrhea, 12 were with compensated cirrhosis and 6 with decompensated cirrhosis, which makes a statistical significance with a chi-square result of 7.189, P = 0.027. 41 out of the 52 cases with diagnostic curettage (75.00%) were observed with pathological changes in endomembrane. During the three months to one year follow-up,10 of 67 patients showed effective expectant treatment and 16 cases with hysterectomia complained no postoperative complications. A high frequency of AUB was observed in nonpregnant cirrhosis patients. The main bleeding pattern of the nonpregnant AUB patients with cirrhosis is hypermenorrhea.


Asunto(s)
Cirrosis Hepática/diagnóstico , Cirrosis Hepática/terapia , Hemorragia Uterina/diagnóstico , Hemorragia Uterina/terapia , Femenino , Humanos , Cirrosis Hepática/complicaciones , Persona de Mediana Edad , Estudios Retrospectivos , Hemorragia Uterina/complicaciones
18.
ACS Macro Lett ; 9(7): 969-973, 2020 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-35648609

RESUMEN

The precise synthesis of chiral poly(silyl ether)s remains a challenge, in contrast to the well-studied preparation of poly(silyl ether)s. Herein, an unprecedented approach for the synthesis of optically active poly(silyl ether)s with main-chain chirality has been developed via CuH-catalyzed hydrosilylation polymerization of diketones and silanes. The polymerization features low catalyst loading, mild condition, and broad substrate scope, including a wide range of aromatic diketones and heteroaromatic diketones with excellent yields and enantioselectivities (up to 98% yield and 99% ee). Thermal analysis indicated chiral poly(silyl ether)s exhibit good thermal properties. These enantiomerically enriched poly(silyl ether)s with good thermal stability have a promising application in chiral separation.

20.
PeerJ ; 6: e5191, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30083437

RESUMEN

Cadmium (Cd) toxicity seriously affects the growth and development of plants, so studies on uptake, translocation, and accumulation of Cd in plants are crucial for phytoremediation. However, the molecular mechanism of the plant response to Cd stress remains poorly understood. The main objective of this study was to reveal differentially expressed genes (DEGs) under lower (BT2_5) and higher (BT43) Cd concentration treatments in creeping bentgrass. A total of 463,184 unigenes were obtained from creeping bentgrass leaves using RNA sequencing technology. Observation of leaf tissue morphology showed that the higher Cd concentration damages leaf tissues. Four key transcription factor (TF) families, WRKY, bZIP, ERF, and MYB, are associated with Cd stress in creeping bentgrass. Our findings revealed that these four TFs play crucial roles during the creeping bentgrass response to Cd stress. This study is mainly focused on the molecular characteristics of DEGs under Cd stress using transcriptomic analysis in creeping bentgrass. These results provide novel insight into the regulatory mechanisms of respond to Cd stress and enrich information for phytoremediation.

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