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1.
Environ Sci Technol ; 58(15): 6487-6498, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38579165

RESUMO

The current understanding of multistress interplay assumes stresses occur in perfect synchrony, but this assumption is rarely met in the natural marine ecosystem. To understand the interplay between nonperfectly overlapped stresses in the ocean, we manipulated a multigenerational experiment (F0-F3) to explore how different temporal scenarios of ocean acidification will affect mercury toxicity in a marine copepod Pseudodiaptomus annandalei. We found that the scenario of past acidification aggravated mercury toxicity but current and persistent acidification mitigated its toxicity. We specifically performed a proteomics analysis for the copepods of F3. The results indicated that current and persistent acidification initiated the energy compensation for development and mercury efflux, whereas past acidification lacked the barrier of H+ and had dysfunction in the detoxification and efflux system, providing a mechanistic understanding of mercury toxicity under different acidification scenarios. Furthermore, we conducted a meta-analysis on marine animals, demonstrating that different acidification scenarios could alter the toxicity of several other metals, despite evidence from nonsynchronous scenarios remaining limited. Our study thus demonstrates that time and duration of ocean acidification modulate mercury toxicity in marine copepods and suggests that future studies should move beyond the oversimplified scenario of perfect synchrony in understanding multistress interaction.


Assuntos
Mercúrio , Animais , Mercúrio/toxicidade , Água do Mar , Ecossistema , Concentração de Íons de Hidrogênio , Acidificação dos Oceanos , Metais
2.
PeerJ ; 12: e17183, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560476

RESUMO

Background: PEBP (phosphatidyl ethanolamine-binding protein) is widely found in eukaryotes including plants, animals and microorganisms. In plants, the PEBP family plays vital roles in regulating flowering time and morphogenesis and is highly associated to agronomic traits and yields of crops, which has been identified and characterized in many plant species but not well studied in Tartary buckwheat (Fagopyrum tataricum Gaertn.), an important coarse food grain with medicinal value. Methods: Genome-wide analysis of FtPEBP gene family members in Tartary buckwheat was performed using bioinformatic tools. Subcellular localization analysis was performed by confocal microscopy. The expression levels of these genes in leaf and inflorescence samples were analyzed using qRT-PCR. Results: Fourteen Fagopyrum tataricum PEBP (FtPEBP) genes were identified and divided into three sub-clades according to their phylogenetic relationships. Subcellular localization analysis of the FtPEBP proteins in tobacco leaves indicated that FT- and TFL-GFP fusion proteins were localized in both the nucleus and cytoplasm. Gene structure analysis showed that most FtPEBP genes contain four exons and three introns. FtPEBP genes are unevenly distributed in Tartary buckwheat chromosomes. Three tandem repeats were found among FtFT5/FtFT6, FtMFT1/FtMFT2 and FtTFL4/FtTFL5. Five orthologous gene pairs were detected between F. tataricum and F. esculentum. Seven light-responsive, nine hormone-related and four stress-responsive elements were detected in FtPEBPs promoters. We used real-time PCR to investigate the expression levels of FtPEBPs among two flowering-type cultivars at floral transition time. We found FtFT1/FtFT3 were highly expressed in leaf and young inflorescence of early-flowering type, whereas they were expressed at very low levels in late-flowering type cultivars. Thus, we deduced that FtFT1/FtFT3 may be positive regulators for flowering and yield of Tartary buckwheat. These results lay an important foundation for further studies on the functions of FtPEBP genes which may be utilized for yield improvement.


Assuntos
Fagopyrum , Filogenia , Fagopyrum/genética , Proteínas de Plantas/genética , Genoma de Planta , Etanolaminas/metabolismo
3.
Compr Rev Food Sci Food Saf ; 23(3): e13334, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38563107

RESUMO

Food waste and byproducts (FWBP) are a global issue impacting economies, resources, and health. Recycling and utilizing these wastes, due to processing and economic constraints, face various challenges. However, valuable components in food waste inspire efficient solutions like active intelligent packaging. Though research on this is booming, its material selectivity, effectiveness, and commercial viability require further analysis. This paper categorizes FWBP and explores their potential for producing packaging from both animal and plant perspectives. In addition, the preparation/fabrication methods of these films/coatings have also been summarized comprehensively, focusing on the advantages and disadvantages of these methods and their commercial adaptability. Finally, the functions of these films/coatings and their ultimate performance in protecting food (meat, dairy products, fruits, and vegetables) are also reviewed systematically. FWBP provide a variety of methods for the application of edible films, including being made into coatings, films, and fibers for food preservation, or extracting active substances directly or indirectly from them (in the form of encapsulation) and adding them to packaging to endow them with functions such as barrier, antibacterial, antioxidant, and pH response. In addition, the casting method is the most commonly used method for producing edible films, but more film production methods (extrusion, electrospinning, 3D printing) need to be tried to make up for the shortcomings of the current methods. Finally, researchers need to conduct more in-depth research on various active compounds from FWBP to achieve better application effects and commercial adaptability.


Assuntos
60659 , Eliminação de Resíduos , Animais , Conservação de Alimentos , Antibacterianos , Frutas
4.
Food Res Int ; 185: 114248, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38658067

RESUMO

Sodium is one of the essential additives in meat processing, but excessive sodium intake may increase risk of hypertension and cardiovascular disease. However, reducing salt content while preserving its preservative effect, organoleptic properties, and technological characteristics poses challenges. In this review, the mechanism of salt reduction of umami substances was introduced from the perspective of gustation-taste interaction, and the effects of the addition of traditional umami substances (amino acids, nucleotides, organic acids(OAs)) and natural umami ingredients (mushrooms, seaweeds, tomatoes, soybeans, tea, grains) on the sensory properties of the meat with reduced-salt contents were summarized. In addition, the impacts of taste enhancers on eating quality (color, sensory, textural characteristics, and water-holding capacity (WHC)), and processing quality (lipid oxidation, pH) of meat products (MP) and their related mechanisms were also discussed. Among them, natural umami ingredients exhibit distinct advantages over traditional umami substances in terms of enhancing quality and nutritional value. On the basis of salt reduction, natural umami ingredients improve the flavor, texture, WHC and antioxidant capacity. This comprehensive review may provide the food industry with a theoretical foundation for mitigating salt consumption through the utilization of umami substances and natural ingredients.


Assuntos
Produtos da Carne , Cloreto de Sódio na Dieta , Paladar , Produtos da Carne/análise , Humanos , Aromatizantes , Animais , Manipulação de Alimentos/métodos , Valor Nutritivo
5.
Sci Total Environ ; 923: 171353, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38432390

RESUMO

Black carbon (BC) exerts a profound and intricate impact on both air quality and climate due to its high light absorption. However, the uncertainty in representing the absorption enhancement of BC in climate models leads to an increased range in the modeled aerosol climate effects. Changes in BC optical properties could result either from atmospheric aging processes or from variations in its sources. In this study, a source-age model for identifying emission sources and aging states presented by University of California at Davis/California Institute of Technology (UCD/CIT) was used to simulate the atmospheric age distribution of BC from different sources and to quantify its impact on the optical properties of BC-containing particles. The results indicate that regions with greater aged BC concentrations do not correspond to regions with higher BC emissions due to atmospheric transport. High concentrations of aged BC are found in northern Yangtze River Delta (YRD) regions during summer. The chemical compositions of particles from different sources and with different atmospheric ages differ significantly. BC and primary organic aerosols (POA) are dominating in Traffic-dominated source while other components dominate in Industry-dominated source. As the atmospheric age increases, the mass fraction of secondary inorganic aerosols rises. Compared to the original model, the simulated mass absorption cross section of BC particles in the source-age model decreases while the single scattering albedo increases. This compensates for ~11 % of the overestimation of the simulated BC direct radiative forcing. Our study highlights that incorporating atmospheric age and source information into models can greatly improve the estimation of optical properties of BC-containing particles and deepen our understanding of their climate effects.

6.
Crit Rev Food Sci Nutr ; : 1-23, 2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38523442

RESUMO

Muscle foods, valued for their significant nutrient content such as high-quality protein, vitamins, and minerals, are vulnerable to adulteration and fraud, stemming from dishonest vendor practices and insufficient market oversight. Traditional analytical methods, often limited to laboratory-scale., may not effectively detect adulteration and fraud in complex applications. Raman spectroscopy (RS), encompassing techniques like Surface-enhanced RS (SERS), Dispersive RS (DRS), Fourier transform RS (FTRS), Resonance Raman spectroscopy (RRS), and Spatially offset RS (SORS) combined with chemometrics, presents a potent approach for both qualitative and quantitative analysis of muscle food adulteration. This technology is characterized by its efficiency, rapidity, and noninvasive nature. This paper systematically summarizes and comparatively analyzes RS technology principles, emphasizing its practicality and efficacy in detecting muscle food adulteration and fraud when combined with chemometrics. The paper also discusses the existing challenges and future prospects in this field, providing essential insights for reviews and scientific research in related fields.

7.
Noncoding RNA Res ; 9(2): 437-446, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38511064

RESUMO

Hepatocellular carcinoma (HCC) is one of the most aggressive and refractory cancers due to its high propensity to metastasize and the unavailability of efficacious treatments. Circular RNAs (circRNAs) participate in diverse biological activities in human cancers. Here, we detected the upregulation of a novel circRNA, circZCCHC2 (hsa_circ_0000854), in HCC samples and cells. The upregulation indicated an unfavorable prognosis in HCC patients. CircZCCHC2 accelerated cell growth and metastasis in vitro and tumorigenicity in vivo. Mechanistic investigations revealed that circZCCHC2 regulated BTBD7 expression by sponging miR-936. Moreover, the suppression of malignancy caused by circZCCHC2 knockdown could be sufficiently reversed by miR-936 inhibition. Additionally, the suppressed Rho/ROCK2 pathway conferred by circZCCHC2 knockdown could be restored by inhibiting miR-936 expression. Collectively, our findings reveal that circZCCHC2 plays an oncogenic role of in HCC progression by modulating the miR-936/BTBD7/Rho/ROCK2 pathway.

8.
J Environ Manage ; 354: 120278, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38354616

RESUMO

The blue carbon ecosystem, including the salt marsh ecosystem, possesses a significant carbon sequestration potential. Therefore, accurately quantifying the carbon storage within such ecosystems is crucial for the adequate accounting of carbon sequestration. The present work chose a Spartina alterniflora ecosystem in the Xiaogan Island (China) as the study area (approximately 11 ha), and employed the Bayesian maximum entropy (BME) approach to assimilate both hard organic carbon (OC) data and soft OC data measured from 2 cm and 10 cm stratified samples. A 3-dimensional model was developed for space-time OC estimation purposes based on the sediment chronology results. The 10-fold BME cross validation results demonstrated a high estimation accuracy, with the R2, RMSE and MAE values equal to 0.8564, 0.1026 % and 0.0748 %, respectively. A noteworthy outcome was the BME-generated carbon storage density maps with 1 m spatial resolution. These maps revealed that the carbon storage density at the top 30 cm sediment depth in the stable zone (with elder stand age of S. alterniflora) was higher than that in the rapid expansion zone, i.e., 71.79 t/ha vs. 69.82 t/ha, respectively. Additionally, the study found that the averaged carbon burial rate and the total carbon storage at the top 30 cm sediment depth across the study area were 266 g C/m2/yr and 781.50 t, respectively. Lastly, the proposed BME-based framework of carbon storage estimation was found to be versatile and applicable to other blue carbon ecosystems. This approach can foster the development of a standardized carbon sink metrological methodology for diverse blue carbon ecosystems.


Assuntos
Ecossistema , Áreas Alagadas , Carbono/análise , Teorema de Bayes , Entropia , Poaceae , China , Sequestro de Carbono
9.
Am J Case Rep ; 25: e942475, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38303503

RESUMO

BACKGROUND Multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSDs) are 2 similar but distinct diseases. These diseases were difficult to distinguish from each other until aquaporin-4-IgG (AQP-4-IgG) was discovered. The accurate identification of these 2 diseases is crucial for appropriate drug treatment in clinical practice. Herein, we report a case of AQP-4-IgG seroconversion with magnetic resonance imaging (MRI) findings suggestive of MS. CASE REPORT A 54-year-old woman developed weakness in her right lower extremity that gradually returned to normal 4 years ago. Recently, she was admitted to the hospital for numbness and weakness of both lower limbs and the right upper limb for more than 10 days. The clinical and MRI features of the patient suggested a high susceptibility for misdiagnosis of MS. However, careful observation of the MRI revealed the presence of atypical MS lesions ("red flag" signs), indicating the possibility of other diagnoses in this patient. After further examination, serum AQP-4-IgG was detected, suggesting the potential presence of another disorder, NMOSD, in the patient. CONCLUSIONS Attention should be given to the identification of MS MRI "red flag" signs. Even for patients with a high suspicion of MS, it is necessary to conduct antibody tests for AQP-4-IgG, MOG-IgG and other relevant markers to screen for associated diseases because MS disease-modifying therapy approaches may lead to a deterioration in the state of NMOSD patients. Analyzing this case can help us to further distinguish the differences between these 2 types of diseases, which has important practical clinical value.


Assuntos
Esclerose Múltipla , Feminino , Humanos , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Glicoproteína Mielina-Oligodendrócito , Autoanticorpos , Aquaporina 4 , Neuroimagem , Imunoglobulina G
10.
J Clin Neurosci ; 119: 185-192, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38113581

RESUMO

BACKGROUND: Previous studies have linked vitamin D deficiency with autoimmune diseases, and recent research has found low vitamin D levels in neuromyelitis optica spectrum disorder (NMOSD) patients. We aimed to determine the variances in serum 25(OH)D levels between NMOSD patients and healthy controls. METHODS: We searched English and Chinese databases (PubMed, Embase, Cochrane Library, Web of Science, CBM, CNKI, WanFang Med, VIP) for observational studies related to serum 25(OH)D levels in NMOSD patients published up to August 24, 2023. We included studies with healthy controls and compared serum 25(OH)D levels between NMOSD patients and controls. We computed the mean difference (MD) and 95% confidence interval (CI) for continuous variables to evaluate serum 25(OH)D levels and combined odds ratios (ORs) and 95% CIs for dichotomized 25(OH)D data. RESULTS: Six papers were selected for meta-analysis, including 794 participants (347 in the NMOSD group and 447 in the healthy control group). Meta-analysis showed significantly lower serum 25(OH)D levels in the NMOSD group (MD: -7.83, 95 % CI: -10.99 to -4.68). The risk of 25(OH)D deficiency was 23.36 times higher in the NMOSD group (OR: 23.36, 95 % CI: 0.85 to 640.76, p = 0.06>0.05), with a 94 % occurrence rate. There was no significant difference in the risk of having sufficient 25(OH)D between the groups (p = 0.12>0.05). CONCLUSION: NMOSD patients have lower serum 25(OH)D levels than healthy controls. However, the current research results do not provide evidence for a causal relationship between serum 25(OH)D levels and the onset of NMOSD. Routine vitamin D supplementation may be advantageous for patients with NMOSD.


Assuntos
Neuromielite Óptica , Deficiência de Vitamina D , Humanos , Vitamina D , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia
11.
Nat Commun ; 14(1): 8399, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38110425

RESUMO

Fungal pathogens typically use secreted effector proteins to suppress host immune activators to facilitate invasion. However, there is rarely evidence supporting the idea that fungal secretory proteins contribute to pathogenesis by transactivating host genes that suppress defense. We previously found that pathogen Magnaporthe oryzae induces rice Bsr-d1 to facilitate infection and hypothesized that a fungal effector mediates this induction. Here, we report that MoSPAB1 secreted by M. oryzae directly binds to the Bsr-d1 promoter to induce its expression, facilitating pathogenesis. Amino acids 103-123 of MoSPAB1 are required for its binding to the Bsr-d1 promoter. Both MoSPAB1 and rice MYBS1 compete for binding to the Bsr-d1 promoter to regulate Bsr-d1 expression. Furthermore, MoSPAB1 homologues are highly conserved among fungi. In particular, Colletotrichum fructicola CfSPAB1 and Colletotrichum sublineola CsSPAB1 activate kiwifruit AcBsr-d1 and sorghum SbBsr-d1 respectively, to facilitate pathogenesis. Taken together, our findings reveal a conserved module that may be widely utilized by fungi to enhance pathogenesis.


Assuntos
Ascomicetos , Magnaporthe , Oryza , Oryza/genética , Magnaporthe/genética , Ascomicetos/metabolismo , Transporte Biológico , Doenças das Plantas/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
12.
Front Plant Sci ; 14: 1263966, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37790794

RESUMO

The vesicle trafficking apparatus is a fundamental machinery to maintain the homeostasis of membrane-enclosed organelles in eukaryotic cells. Thus, it is broadly conserved in eukaryotes including plants. Intensive studies in the model organisms have produced a comprehensive picture of vesicle trafficking in yeast and human. However, with respect to the vesicle trafficking of plants including rice, our understanding of the components and their coordinated regulation is very limited. At present, several vesicle trafficking apparatus components and cargo proteins have been identified and characterized in rice, but there still remain large unknowns concerning the organization and function of the rice vesicle trafficking system. In this review, we outline the main vesicle trafficking pathways of rice based on knowledge obtained in model organisms, and summarize current advances of rice vesicle trafficking. We also propose to develop methodologies applicable to rice and even other crops for further exploring the mysteries of vesicle trafficking in plants.

13.
Rice (N Y) ; 16(1): 42, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37733139

RESUMO

Plant disease is a threat to global food security. Breeding crops carrying broad-spectrum resistance loci is an effective way to control infectious disease. Disease-resistant mutants are valuable resources for deciphering the underlying mechanisms of plant immunity and could provide genetic loci to generate disease-resistant crops. Here, we identified a rice mutant, rbr7 (rice blast resistance 7), that confers resistance against different strains of Magnaporthe oryzae. Disease-mimicking necrotic lesions started to appear on the leaves of rbr7 four weeks after sowing. Histochemical analysis revealed reactive oxygen species accumulation and cell death accompanied by spontaneous lesion formation in rbr7. Map-based cloning and bulk segregation analysis showed a 2855 bp fragment deletion on chromosome 5, leading to the disruption of the LOC_Os05g28480-coding protein. Transgenic rbr7 complementation plants showed compromised resistance to rice blast, indicating that LOC_Os05g28480, or Rbr7, regulates the rice immune response. Rbr7 encodes a small protein of unknown function with 85 amino acids. Transcriptomic analysis revealed that disruption of RBR7 led to the upregulation of genes responding to salicylic acid, systemic acquired resistance and pathogenesis-related genes. Taken together, our findings reveal insights into a novel small protein involved in regulating plant resistance to rice blast and provide a potential target for crop breeding.

14.
J Am Chem Soc ; 145(39): 21170-21175, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37605370

RESUMO

The first total syntheses of polycyclic diterpenes phomopsene (1), methyl phomopsenonate (2), and iso-phomopsene (3) have been accomplished through the unusual cascade reorganization of C-C single bonds. This approach features: (i) a synergistic Nazarov cyclization/double ring expansions in one-step, developed by authors, to rapid and stereospecific construction of the 5/5/5/5 tetraquinane scaffold bearing contiguous quaternary centers and (ii) a one-pot strategic ring expansion through Beckmann fragmentation/recombination to efficiently assemble the requisite 5/5/6/5 tetracyclic skeleton of the target molecules 1-3. This work enables us to determine that the correct structure of iso-phomopsene is, in fact, the C7 epimer of the originally assigned structure. Finally, the absolute configurations of three target molecules were confirmed through enantioselective synthesis.

15.
Phys Rev Lett ; 130(16): 168101, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37154633

RESUMO

We report measurements of the onset temperature of rejuvenation, T_{onset}, and the fictive temperature, T_{f}, for ultrathin stable polystyrene with thicknesses from 10 to 50 nm prepared by physical vapor deposition. We also measure the T_{g} of these glasses on the first cooling after rejuvenation as well as the density anomaly of the as-deposited material. Both the T_{g} in rejuvenated films and the T_{onset} in stable films decrease with decreasing film thickness. The T_{f} value increases for decreasing film thickness. The density increase typical of stable glasses also decreases with decreasing film thickness. Collectively, the results are consistent with a decrease in apparent T_{g} due to the existence of a mobile surface layer, as well as a decrease in the film stability as the thickness is decreased. The results provide the first self-consistent set of measurements of stability in ultrathin films of stable glass.

16.
J Chem Phys ; 158(9): 094901, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36889949

RESUMO

We have studied the liquid-like response of the surface of vapor-deposited glassy films of polystyrene to the introduction of gold nanoparticles on the surface. The build-up of polymer material was measured as a function of time and temperature for both as-deposited films, as well as films that have been rejuvenated to become normal glasses cooled from the equilibrium liquid. The temporal evolution of the surface profile is well described by the characteristic power law of capillary-driven surface flows. In all cases, the surface evolution of the as-deposited films and the rejuvenated films is enhanced compared to bulk and is not easily distinguishable from each other. The temperature dependence of the measured relaxation times determined from the surface evolution is found to be quantitatively comparable to similar studies for high molecular weight spincast polystyrene. Comparisons to numerical solutions of the glassy thin film equation provide quantitative estimates of the surface mobility. For temperatures sufficiently close to the glass-transition temperature, particle embedding is also measured and used as a probe of bulk dynamics, and, in particular, bulk viscosity.

17.
Environ Int ; 166: 107369, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35772313

RESUMO

Particulate nitrate (pNO3) is now becoming the principal component of PM2.5 during severe winter haze episodes in many cities of China. To gain a comprehensive understanding of the key factors controlling pNO3 formation and driving its trends, we reviewed the recent pNO3 modeling studies which mainly focused on the formation mechanism and recent trends of pNO3 as well as its responses to emission controls in China. The results indicate that although recent chemical transport models (CTMs) can reasonably capture the spatial-temporal variations of pNO3, model-observation biases still exist due to large uncertainties in the parameterization of dinitrogen pentoxide (N2O5) uptake and ammonia (NH3) emissions, insufficient heterogeneous reaction mechanism, and the predicted low sulfate concentrations in current CTMs. The heterogeneous hydrolysis of N2O5 dominates nocturnal pNO3 formation, however, the contribution to total pNO3 varies among studies, ranging from 21.0% to 51.6%. Moreover, the continuously increasing PM2.5 pNO3 fraction in recent years is mainly due to the decreased sulfur dioxide emissions, the enhanced atmospheric oxidation capacity (AOC), and the weakened nitrate deposition. Reducing NH3 emissions is found to be the most effective control strategy for mitigating pNO3 pollution in China. This review suggests that more field measurements are needed to constrain the parameterization of heterogeneous N2O5 and nitrogen dioxide (NO2) uptake. Future studies are also needed to quantify the relationships of pNO3 to AOC, O3, NOx, and volatile organic compounds (VOCs) in different regions of China under different meteorological conditions. Research on multiple-pollutant control strategies involving NH3, NOX, and VOCs is required to mitigate pNO3 pollution, especially during severe winter haze events.

18.
Nat Commun ; 13(1): 2335, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35484150

RESUMO

A modular and efficient method for constructing angular tri-carbocyclic architectures containing quaternary carbon center(s) from 1,3-dicycloalkylidenyl ketones is established, which involves an unconventional synergistic cascade of a Nazarov cyclization and two ring expansions. It features high selectivity, mild conditions and convenient operation, wide scope and easy availability of substrate. Substitution with R1 and R2 at the 4πe-system with electron-donating group favors this reaction, while that with electron-withdrawing group or proton disfavors. The electron-donating group as R1 directs the initial ring expansion at its own site, while the p-π- or n-π- associated substituent as R2 favors selectively the later ring expansion near its location because of the beneficial maintenance of an original conjugated system. The stereoselectivity has proved to be governed by either the steric effect of R3 and R4 at the expanded rings, or the migration ability of the migrating atom. Density Functional Theory calculation suggests the initial Nazarov cyclization would be the rate-determining step. A racemic total synthesis of the natural (±)-waihoensene is realized in 18 steps by use of this methodology.

19.
Plant Biotechnol J ; 20(7): 1311-1326, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35315196

RESUMO

Plant transcription factors (TFs), such as basic helix-loop-helix (bHLH) and AT-rich zinc-binding proteins (PLATZ), play critical roles in regulating the expression of developmental genes in cereals. We identified the bHLH protein TaPGS1 (T. aestivum Positive Regulator of Grain Size 1) specifically expressed in the seeds at 5-20 days post-anthesis in wheat. TaPGS1 was ectopically overexpressed (OE) in wheat and rice, leading to increased grain weight (up to 13.81% in wheat and 18.55% in rice lines) and grain size. Carbohydrate and total protein levels also increased. Scanning electron microscopy results indicated that the starch granules in the endosperm of TaPGS1 OE wheat and rice lines were smaller and tightly embedded in a proteinaceous matrix. Furthermore, TaPGS1 was bound directly to the E-box motif at the promoter of the PLATZ TF genes TaFl3 and OsFl3 and positively regulated their expression in wheat and rice. In rice, the OsFl3 CRISPR/Cas9 knockout lines showed reduced average thousand-grain weight, grain width, and grain length in rice. Our results reveal that TaPGS1 functions as a valuable trait-associated gene for improving cereal grain yield.


Assuntos
Grão Comestível , Oryza , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes , Triticum/metabolismo
20.
J Int Med Res ; 50(3): 3000605221090098, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35352586

RESUMO

Patients with pancreatic walled-off necrosis (WON) treated by minimally invasive approaches often require repeated necrosectomy instead of conventional open necrosectomy. A 55-year-old woman with lateral infected pancreatic WON was successfully treated by an infrequently used technique involving an ultrasonic pneumatic lithotripsy system (UPLS) and double-catheter aspirated lavage through a percutaneous drainage tract. No perioperative complications occurred. The mean operating time of the repeated procedures was 35 minutes (range, 25-48 minutes). The total hospitalization stay was 46 days, and no recurrence of the fluid collection was observed during the 15-month follow-up period. UPLS-assisted necrosectomy and double-catheter aspirated lavage is an alternative technique for lateral WON that fails to improve by percutaneous drainage. It efficiently combines disintegration and aspiration procedures and can be safely repeated under total intravenous anesthesia through sinus tracts.


Assuntos
Litotripsia , Ultrassom , Cateteres , Drenagem/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Necrose , Estudos Retrospectivos , Irrigação Terapêutica
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