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1.
Nature ; 626(7997): 105-110, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38297175

RESUMEN

Silicon solar cells are a mainstay of commercialized photovoltaics, and further improving the power conversion efficiency of large-area and flexible cells remains an important research objective1,2. Here we report a combined approach to improving the power conversion efficiency of silicon heterojunction solar cells, while at the same time rendering them flexible. We use low-damage continuous-plasma chemical vapour deposition to prevent epitaxy, self-restoring nanocrystalline sowing and vertical growth to develop doped contacts, and contact-free laser transfer printing to deposit low-shading grid lines. High-performance cells of various thicknesses (55-130 µm) are fabricated, with certified efficiencies of 26.06% (57 µm), 26.19% (74 µm), 26.50% (84 µm), 26.56% (106 µm) and 26.81% (125 µm). The wafer thinning not only lowers the weight and cost, but also facilitates the charge migration and separation. It is found that the 57-µm flexible and thin solar cell shows the highest power-to-weight ratio (1.9 W g-1) and open-circuit voltage (761 mV) compared to the thick ones. All of the solar cells characterized have an area of 274.4 cm2, and the cell components ensure reliability in potential-induced degradation and light-induced degradation ageing tests. This technological progress provides a practical basis for the commercialization of flexible, lightweight, low-cost and highly efficient solar cells, and the ability to bend or roll up crystalline silicon solar cells for travel is anticipated.

2.
Nature ; 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39236747

RESUMEN

Two-terminal monolithic perovskite-silicon tandem solar cells demonstrate huge advantages in power conversion efficiency (PCE) compared to their respective single-junction counterparts1,2. However, suppressing interfacial recombination at the wide-bandgap perovskite/electron transport layer interface, without compromising its superior charge transport performance, remains a significant challenge for perovskite-silicon tandem cells3,4. By exploiting the nanoscale discretely distributed LiF ultrathin layer followed by an additional deposition of diammonium diiodide molecule, we have devised a bilayer intertwined passivation strategy that combines efficient electron extraction with further suppression of nonradiative recombination. We constructed perovskite-silicon tandem devices on double-side textured Czochralski (CZ)-based silicon heterojunction cell, which featured a mildly-textured front surface and a heavily-textured rear surface, leading to simultaneously enhanced photocurrent and uncompromised rear passivation. The resulting perovskite-silicon tandem achieved an independently certified stabilized PCE of 33.89%, accompanied by an impressive fill factor (FF) of 83.0% and an open-circuit voltage (Voc) of nearly 1.97 volts. To our knowledge, this represents the first reported certified efficiency of a two-junction tandem solar cell exceeding the single-junction Shockley-Queisser limit of 33.7%.

3.
Plant J ; 118(2): 549-564, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38184780

RESUMEN

Epigenetic regulation of gene expression plays a crucial role in plant development and environmental adaptation. The H3K4me3 and H3K27me3 have not only been discovered in the regulation of gene expression in multiple biological processes but also in responses to abiotic stresses in plants. However, evidence for the presence of both H3K4me3 and H3K27me3 on the same nucleosome is sporadic. Cold-induced deposition of bivalent H3K4me3-H3K27me3 modifications and nucleosome depletion over a considerable number of active genes is documented in potato tubers and provides clues on an additional role of the bivalent modifications. Limited by the available information of genes encoding PcG/TrxG proteins as well as their corresponding mutants in potatoes, the molecular mechanism underlying the cold-induced deposition of the bivalent mark remains elusive. In this study, we found a similar deposition of the bivalent H3K4me3-H3K27me3 mark over 2129 active genes in cold-treated Arabidopsis Col-0 seedlings. The expression levels of the bivalent mark-associated genes tend to be independent of bivalent modification levels. However, these genes were associated with greater chromatin accessibility, presumably to provide a distinct chromatin environment for gene expression. In mutants clf28 and lhp1, failure to deposit H3K27me3 in active genes upon cold treatment implies that the CLF is potentially involved in cold-induced deposition of H3K27me3, with assistance from LHP1. Failure to deposit H3K4me3 during cold treatment in atx1-2 suggests a regulatory role of ATX1 in the deposition of H3K4me3. In addition, we observed a cold-induced global reduction in nucleosome occupancy, which is potentially mediated by LHP1 in an H3K27me3-dependent manner.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Histonas/genética , Histonas/metabolismo , Nucleosomas/genética , Nucleosomas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Epigénesis Genética , Proteínas de Arabidopsis/metabolismo , Cromatina/genética , Cromatina/metabolismo , Regulación de la Expresión Génica de las Plantas/genética
4.
Genomics ; 116(1): 110755, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38061481

RESUMEN

Acute lung injury (ALI) is a serious illness that develops suddenly, progresses rapidly, has a poor treatment response and a high mortality rate. Studies have found that circular RNAs (circRNA) play a critical role in several diseases, but their role in ALI remains unclear. The aim of this study was to identify circRNAs that are associated with ALI and investigate their potential molecular mechanisms. A comparison of lung circRNA and microRNA expression profiles in mice with ALI and controls was performed by RNA-sequencing. A bioinformatic analysis was conducted to identify differentially expressed (DE) RNAs, to construct competitive endogenous RNA (ceRNA) networks, and to analyze their function and pathways. Then, a protein-protein interaction (PPI) network was generated by the Search Tool for the Retrieval of Interacting Genes database, and hub genes were identified using Cytoscape. Furthermore, a key ceRNA subnetwork was constructed based on these hub genes. Overall, we found 239 DE circRNAs and 42 DE microRNAs in ALI mice compared to controls. Additionally, the molecular mechanism of ALI was further understood by building ceRNA networks based on these DE genes. ALI-induced circRNAs are mostly function in the inflammatory response and metabolic processes. Moreover, DE circRNAs are primarily involved in the nuclear factor (NF)-kappa B and PI3K-Akt signaling pathways. Seven hub genes were derived from the PPI network of 191 genes, followed by the construction of circRNA-miRNA-hub gene subnetworks. In this study, circRNA profiles are remarkably changed in mice with LPS-triggered ALI, and their potential contribution to the disease is revealed.


Asunto(s)
Lesión Pulmonar Aguda , MicroARNs , Ratones , Animales , ARN Circular/genética , Lipopolisacáridos/toxicidad , RNA-Seq , ARN Mensajero/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Perfilación de la Expresión Génica , MicroARNs/metabolismo , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/genética , Redes Reguladoras de Genes
5.
J Cell Mol Med ; 28(17): e18535, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39267250

RESUMEN

Luteolin, a commonly used traditional Chinese medicine, has been utilized for several decades in the treatment of hepatocellular carcinoma (HCC). Previous research has demonstrated its anti-tumour efficacy, but its underlying mechanism remains unclear. This study aimed to assess the therapeutic effects of luteolin in H22 tumour-bearing mice. luteolin effectively inhibited the growth of solid tumours in a well-established mouse model of HCC. High-throughput sequencing revealed that luteolin treatment could enhance T-cell activation, cell chemotaxis and cytokine production. In addition, luteolin helped sustain a high ratio of CD8+ T lymphocytes in the spleen, peripheral blood and tumour tissues. The effects of luteolin on the phenotypic and functional changes in tumour-infiltrating CD8+ T lymphocytes were also investigated. Luteolin restored the cytotoxicity of tumour-infiltrating CD8+ T lymphocytes in H22 tumour-bearing mice. The CD8+ T lymphocytes exhibited intensified phenotype activation and increased production of granzyme B, IFN-γ and TNF-α in serum. The combined administration of luteolin and the PD-1 inhibitor enhanced the anti-tumour effects in H22 tumour-bearing mice. Luteolin could exert an anti-tumour immune response by inducing CD8+ T lymphocyte infiltration and enhance the anti-tumour effects of the PD-1 inhibitor on H22 tumour-bearing mice.


Asunto(s)
Linfocitos T CD8-positivos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Luteolina , Linfocitos Infiltrantes de Tumor , Luteolina/farmacología , Luteolina/uso terapéutico , Animales , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/patología , Ratones , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/efectos de los fármacos , Linfocitos Infiltrantes de Tumor/metabolismo , Línea Celular Tumoral , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/inmunología , Citocinas/metabolismo , Masculino , Granzimas/metabolismo , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Ratones Endogámicos C57BL
6.
J Am Chem Soc ; 146(25): 17438-17445, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38860872

RESUMEN

Metal-organic polyhedra (MOPs) can exhibit tunable porosity and functionality, suggesting potential for applications such as molecular separations. MOPs are typically constructed by the bottom-up multicomponent self-assembly of organic ligands and metal ions, and the final functionality can be hard to program. Here, we used trianglsalen macrocycles as preorganized building blocks to assemble octahedral-shaped MOPs. The resultant MOPs inherit most of the preorganized properties of the macrocyclic ligands, including their well-defined cavities and chirality. As a result, the porosity in the MOPs could be tuned by modifying the structure of the macrocycle building blocks. Using this strategy, we could systematically enlarge the size of the MOPs from 26.3 to 32.1 Å by increasing the macrocycle size. The family of MOPs shows experimental surface areas of up to 820 m2/g, and they are stable in water. One of these MOPs can efficiently separate the rare gases Xe from Kr because the prefabricated macrocyclic windows of MOPs can be modified to sit at the Xe/Kr size cutoff range.

7.
Biochem Biophys Res Commun ; 738: 150524, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39151294

RESUMEN

Diabetic nephropathy (DN) is an important cause of death in diabetes patients, which is mainly due to its complex pathogenesis. Here, we explored the role of N6-methyladenosine (m6A) RNA methylation in DN development. Renal tubular epithelial cells from DN patients and experimental DN mice treated with streptozotocin (STZ) exhibited a considerable increase in METTL14 and WTAP expression as well as overall m6A methylation. Knocking down the expression of METTL14 and WTAP inhibited the migration and proliferation of tubular epithelial cells. MeRIP-seq analysis of the renal tissues of DN patients revealed that the genes with elevated m6A methylation were concentrated in the Wnt/ß-Catenin signaling pathway. Dickkopf homolog 3 (DKK3) was screened out as the gene with the most significant increase in m6A methylation. In addition, the expression change pattern of DKK3 under DN circumstances is in line with those of METTL14 and WTAP. DKK3's m6A methylation sites were confirmed to be located in the 3'UTR region, which is how METTL14 and WTAP improved DKK3's mRNA stability. Finally, YTHDF1, a m6A reader, was demonstrated to recognize m6A-methylated DKK3 and promote DKK3 expression.

8.
BMC Med ; 22(1): 206, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769523

RESUMEN

BACKGROUND: Numerous studies have been conducted to investigate the relationship between ABO and Rhesus (Rh) blood groups and various health outcomes. However, a comprehensive evaluation of the robustness of these associations is still lacking. METHODS: We searched PubMed, Web of Science, Embase, Scopus, Cochrane, and several regional databases from their inception until Feb 16, 2024, with the aim of identifying systematic reviews with meta-analyses of observational studies exploring associations between ABO and Rh blood groups and diverse health outcomes. For each association, we calculated the summary effect sizes, corresponding 95% confidence intervals, 95% prediction interval, heterogeneity, small-study effect, and evaluation of excess significance bias. The evidence was evaluated on a grading scale that ranged from convincing (Class I) to weak (Class IV). We assessed the certainty of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation criteria (GRADE). We also evaluated the methodological quality of included studies using the A Measurement Tool to Assess Systematic Reviews (AMSTAR). AMSTAR contains 11 items, which were scored as high (8-11), moderate (4-7), and low (0-3) quality. We have gotten the registration for protocol on the PROSPERO database (CRD42023409547). RESULTS: The current umbrella review included 51 systematic reviews with meta-analysis articles with 270 associations. We re-calculated each association and found only one convincing evidence (Class I) for an association between blood group B and type 2 diabetes mellitus risk compared with the non-B blood group. It had a summary odds ratio of 1.28 (95% confidence interval: 1.17, 1.40), was supported by 6870 cases with small heterogeneity (I2 = 13%) and 95% prediction intervals excluding the null value, and without hints of small-study effects (P for Egger's test > 0.10, but the largest study effect was not more conservative than the summary effect size) or excess of significance (P < 0.10, but the value of observed less than expected). And the article was demonstrated with high methodological quality using AMSTAR (score = 9). According to AMSTAR, 18, 32, and 11 studies were categorized as high, moderate, and low quality, respectively. Nine statistically significant associations reached moderate quality based on GRADE. CONCLUSIONS: Our findings suggest a potential relationship between ABO and Rh blood groups and adverse health outcomes. Particularly the association between blood group B and type 2 diabetes mellitus risk.


Asunto(s)
Sistema del Grupo Sanguíneo ABO , Metaanálisis como Asunto , Estudios Observacionales como Asunto , Sistema del Grupo Sanguíneo Rh-Hr , Revisiones Sistemáticas como Asunto , Humanos , Revisiones Sistemáticas como Asunto/métodos , Estudios Observacionales como Asunto/métodos
9.
Small ; : e2401831, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38733226

RESUMEN

Quasi-2D perovskites have attracted much attention in perovskite photovoltaics due to their excellent stability. However, their photoelectric conversion efficiency (PCE) still lags 3D counterparts, particularly with high short-circuit current (JSC) loss. The quantum confinement effect is pointed out to be the sole reason, which introduces widened bandgap and poor exciton dissociation, and undermines the light capture and charge transport. Here, the gradient incorporation of formamidinium (FA) cations into quasi-2D perovskite is proposed to address this issue. It is observed that FA prefers to incorporate into the larger n value phases near the film surface compared to the smaller n value phases in the bulk, resulting in a narrow bandgap and gradient structure within the film. Through charge dynamic analysis using in situ light-dark Kelvin probe force microscopy and transient absorption spectroscopy, it is demonstrated that incorporating 10% FA significantly facilitates efficient charge transfer between low n-value phases in the bulk and high n-value nearby film surface, leading to reduced charge accumulation. Ultimately, the device based on (AA)2(MA0.9FA0.1)4Pb5I16, where AA represents n-amylamine renowned for its exceptional environmental stability as a bulky organic ligand, achieves an impressive power conversion efficiency (PCE) of 18.58% and demonstrates enhanced illumination and thermal stability.

10.
Toxicol Appl Pharmacol ; 491: 117050, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39111554

RESUMEN

Benzo[a]pyrene (BaP) is a ubiquitous environmental pollutant posing various toxicity effects on organisms. Previous studies demonstrated that BaP could induce hepatotoxicity, while the underlying mechanism remains incompletely elucidated. In this study, a comprehensive strategy including network toxicology, transcriptomics and gut microbiomics was applied to investigate the hepatotoxicity and the associated mechanism of BaP exposure in mice. The results showed that BaP induced liver damage, liver oxidative stress and hepatic lipid metabolism disorder. Mechanistically, BaP may disrupt hepatic lipid metabolism through increasing the uptake of free fatty acid (FFA), promoting the synthesis of FA and triglyceride (TG) in the liver and suppressing lipid synthesis in white adipose tissue. Moreover, integrated network toxicology and hepatic transcriptomics revealed that BaP induced hepatotoxicity by acting on several core targets, such as signal transducer and activator of transcription 1 (STAT1), C-X-C motif chemokine ligand 10 (CXCL10) and toll-like receptor 2 (TLR2). Further analysis suggested that BaP inhibited JAK2-STAT3 signaling pathway, as supported by molecular docking and western blot. The 16S rRNA sequencing showed that BaP changed the composition of gut microbiota which may link to the hepatotoxicity based on the correlation analysis. Taken together, this study demonstrated that BaP caused liver injury, hepatic lipid metabolism disorder and gut microbiota dysbiosis, providing novel insights into the hepatotoxic mechanism induced by BaP exposure.


Asunto(s)
Benzo(a)pireno , Enfermedad Hepática Inducida por Sustancias y Drogas , Microbioma Gastrointestinal , Hígado , Animales , Benzo(a)pireno/toxicidad , Microbioma Gastrointestinal/efectos de los fármacos , Ratones , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Masculino , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Transcriptoma/efectos de los fármacos , Metabolismo de los Lípidos/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Ratones Endogámicos C57BL , Transducción de Señal/efectos de los fármacos , Disbiosis/inducido químicamente , Contaminantes Ambientales/toxicidad
11.
Arch Microbiol ; 206(9): 381, 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39153128

RESUMEN

The bacterial type II toxin-antitoxin (TA) system is a rich genetic element that participates in various physiological processes. Aeromonas veronii is the main bacterial pathogen threatening the freshwater aquaculture industry. However, the distribution of type II TA system in A. veronii was seldom documented and its roles in the life activities of A. veronii were still unexplored. In this study, a novel type II TA system AvtA-AvtT was predicted in a fish pathogen Aeromonas veronii biovar sobria with multi-drug resistance using TADB 2.0. Through an Escherichia coli host killing and rescue assay, we demonstrated that AvtA and AvtT worked as a genuine TA system, and the predicted toxin AvtT actually functioned as an antitoxin while the predicted antitoxin AvtA actually functioned as a toxin. The binding ability of AvtA with AvtT proteins were confirmed by dot blotting analysis and co-immunoprecipitation assay. Furthermore, we found that the toxin and antitoxin labelled with fluorescent proteins were co-localized. In addition, it was found that the transcription of AvtAT bicistronic operon was repressed by the AvtAT protein complex. Deletion of avtA gene and avtT gene had no obvious effect on the drug susceptibility. This study provides first characterization of type II TA system AvtA-AvtT in aquatic pathogen A. veronii.


Asunto(s)
Aeromonas veronii , Proteínas Bacterianas , Sistemas Toxina-Antitoxina , Aeromonas veronii/genética , Aeromonas veronii/metabolismo , Sistemas Toxina-Antitoxina/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Toxinas Bacterianas/metabolismo , Toxinas Bacterianas/genética , Operón , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/efectos de los fármacos , Antitoxinas/genética , Antitoxinas/metabolismo , Regulación Bacteriana de la Expresión Génica
12.
Antonie Van Leeuwenhoek ; 117(1): 46, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38427093

RESUMEN

The fast-growing rhizobia-like strains S101T and S153, isolated from root nodules of soybean (Glycine max) in Sichuan, People's Republic of China, underwent characterization using a polyphasic taxonomy approach. The strains exhibited growth at 20-40 °C (optimum, 28 °C), pH 4.0-10.0 (optimum, pH 7.0) and up to 2.0% (w/v) NaCl (optimum, 0.01%) on Yeast Mannitol Agar plates. The 16S rRNA gene of strain S101T showed 98.4% sequence similarity to the closest type strain, Ciceribacter daejeonense L61T. Major cellular fatty acids in strain S101T included summed feature 8 (C18:1ω7c and/or C18:1ω6c) and C19:0 cyclo ω8c. The predominant quinone was ubiquinone-10. The polar lipids of strain S101T included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmethyl ethanolamine, phosphatidyl ethanolamine, amino phospholipid, unidentified phosphoglycolipid and unidentified amino-containing lipids. The DNA G + C contents of S101T and S153 were 61.1 and 61.3 mol%, respectively. Digital DNA-DNA hybridization relatedness and average nucleotide identity values between S101T and C. daejeonense L61T were 46.2% and 91.4-92.2%, respectively. In addition, strain S101T promoted the growth of soybean and carried nitrogen fixation genes in its genome, hinting at potential applications in sustainable agriculture. We propose that strains S101T and S153 represent a novel species, named Ciceribacter sichuanensis sp. nov., with strain S101T as the type strain (= CGMCC 1.61309 T = JCM 35649 T).


Asunto(s)
Glycine max , Fosfolípidos , Humanos , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Filogenia , ADN Bacteriano/genética , Fosfolípidos/química , Ácidos Grasos/química , Etanolaminas , China , Técnicas de Tipificación Bacteriana
13.
Plant Cell Rep ; 43(10): 240, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39317879

RESUMEN

KEY MESSAGE: Assembly of PUFA-attached TAGs is intimately correlated to turnover of newly formed membrane lipids in starch-deficient Chlamydomonas exposed to high light and nitrogen stress under air-aerated mixotrophic conditions. Triacylglycerols (TAGs) rich in polyunsaturated fatty acids (PUFAs) in microalgae have attracted extensive attention due to its promising application in nutraceuticals and other high-value compounds. Previous studies revealed that PUFAs accumulated in TAG primarily derived from the dominant membrane lipids, monogalactosyldiacylglycerolipid, digalactosyldiacylglycerol and diacylglycerol-N,N,N-trimethylhomoserine (DGTS), in the model alga Chlamydomonas reinhardtii. However, their respective contribution to PUFA-attached TAG integration has not been clearly deciphered, particularly in starchless Chlamydomonas that hyper-accumulates TAG. In this study, the starchless C. reinhardtii BAFJ5 was mixotrophically cultivated in photobioreactors aerated with air (0.04% CO2), and we monitored the dynamic changes in growth, cellular carbon and nitrogen content, photosynthetic activity, biochemical compositions, and glycerolipid remodeling under high light and nitrogen starvation conditions. The results indicated that multiple PUFAs continually accumulated in total lipids and TAG, and the primary distributors of these PUFAs gradually shifted from membrane lipids to TAG in stress-induced BAFJ5. The stoichiometry analyses showed that the PUFA-attached TAG assembly attributed to turnover of not only the major glycerolipids, but also the phospholipids, phosphatidylethanolamine (PE) and phosphatidylglycerol. Specifically, the augmented C16:3n3 and C18:3n3 in TAG mainly originated from de novo-synthesized galactolipids, while the cumulative C18:3n6 and C18:4n3 in TAG were intimately correlated with conversion of the newly formed DGTS and PE. These findings emphasized significance of PUFA-attached TAG formation dependent on turnover of de novo assembled membrane lipids in starch-deficient Chlamydomonas, beneficial for enhanced production of value-added lipids in microalgae.


Asunto(s)
Chlamydomonas reinhardtii , Ácidos Grasos Insaturados , Lípidos de la Membrana , Triglicéridos , Triglicéridos/metabolismo , Lípidos de la Membrana/metabolismo , Chlamydomonas reinhardtii/metabolismo , Ácidos Grasos Insaturados/metabolismo , Estrés Fisiológico , Almidón/metabolismo , Nitrógeno/metabolismo , Galactolípidos/metabolismo , Fotosíntesis
14.
Food Microbiol ; 120: 104465, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38431317

RESUMEN

Biological antagonists serve as the most important green alternatives to chemical fungicides, a class of microorganism that inhibits the growth of pathogenic fungi to reduce fruit incidence. In this paper, healthy and diseased peach fruit was selected for amplicon sequencing of the epiphytic microbiota on their surface to obtain a comprehensive understanding. Community structure, diversity and LefSe analysis were performed to screen Acetobacter, Muribaculaceae and Burkholderia as the core bacteria, Mycosphaerella, Penicillium and Alternaria as the core fungi, they showed significant differences and were highly enriched. Two strains fungi (Penicillium K3 and N1) and one strain antagonistic bacteria (Burkholderia J2) were isolated. The in intro test results indicated the bacterial suspension, fermentation broth and volatile organic compounds of antagonistic bacteria J2 were able to significantly inhibit pathogen growth. In vivo experiments, peach was stored at 28 °C for 6 days after different treatments, and samples were taken every day. It was found that Burkholderia J2 enhanced peach resistance by increasing the activities of antioxidant-related enzymes such as SOD, POD, PAL, PPO, GR, MDHAR, and DHAR. The results improved that Burkholderia J2 has great biocontrol potential and could be used as a candidate strain for green control of blue mold.


Asunto(s)
Penicillium , Prunus persica , Prunus persica/microbiología , Bacterias/genética , Frutas/microbiología , Alternaria
15.
Mar Drugs ; 22(9)2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39330296

RESUMEN

Alginate lyase is an attractive biocatalyst that can specifically degrade alginate to produce oligosaccharides, showing great potential for industrial and medicinal applications. Herein, an alginate-degrading strain HB236076 was isolated from Sargassum sp. in Qionghai, Hainan, China. The low 16S rRNA gene sequence identity (<98.4%), ANI value (<71.9%), and dDDH value (<23.9%) clearly indicated that the isolate represented a potential novel species of the genus Vibrio. The genome contained two chromosomes with lengths of 3,007,948 bp and 874,895 bp, respectively, totaling 3,882,843 bp with a G+C content of 46.5%. Among 3482 genes, 3332 protein-coding genes, 116 tRNA, and 34 rRNA sequences were predicted. Analysis of the amino acid sequences showed that the strain encoded 73 carbohydrate-active enzymes (CAZymes), predicting seven PL7 (Alg1-7) and two PL17 family (Alg8, 9) alginate lyases. The extracellular alginate lyase from strain HB236076 showed the maximum activity at 50 °C and pH 7.0, with over 90% activity measured in the range of 30-60 °C and pH 6.0-10.0, exhibiting a wide range of temperature and pH activities. The enzyme also remained at more than 90% of the original activity at a wide pH range (3.0-9.0) and temperature below 50 °C for more than 2 h, demonstrating significant thermal and pH stabilities. Fe2+ had a good promoting effect on the alginate lyase activity at 10 mM, increasing by 3.5 times. Thin layer chromatography (TLC) and electrospray ionization mass spectrometry (ESI-MS) analyses suggested that alginate lyase in fermentation broth could catalyze sodium alginate to produce disaccharides and trisaccharides, which showed antimicrobial activity against Shigella dysenteriae, Aeromonas hydrophila, Staphylococcus aureus, Streptococcus agalactiae, and Escherichia coli. This research provided extended insights into the production mechanism of alginate lyase from Vibrio sp. HB236076, which was beneficial for further application in the preparation of pH-stable and thermo-stable alginate lyase and alginate oligosaccharides.


Asunto(s)
Alginatos , Oligosacáridos , Polisacárido Liasas , Vibrio , Polisacárido Liasas/genética , Polisacárido Liasas/metabolismo , Polisacárido Liasas/química , Vibrio/enzimología , Vibrio/genética , Alginatos/metabolismo , Oligosacáridos/metabolismo , Concentración de Iones de Hidrógeno , Genoma Bacteriano , Temperatura , Sargassum , Filogenia , Estabilidad de Enzimas , ARN Ribosómico 16S/genética , China
16.
Genomics ; 115(6): 110747, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37977331

RESUMEN

Placopecten magellanicus (Gmelin, 1791), a deep-sea Atlantic scallop, holds significant commercial value as a benthic marine bivalve along the northwest Atlantic coast. Recognizing its economic importance, the need to reconstruct its genome assembly becomes apparent, fostering insights into natural resources and generic breeding potential. This study reports a high-quality chromosome-level genome of P. magellanicus, achieved through the integration of Illumina short read sequencing, PacBio HiFi sequencing, and Hi-C sequencing techniques. The resulting assembly spans 1778 Mb with a scaffold N50 of 86.71 Mb. An intriguing observation arises - the genome size of P. magellanicus surpasses that of its Pectinidae family peers by 1.80 to 2.46 times. Within this genome, 28,111 protein-coding genes were identified. Comparative genomic analysis involving five scallop species unveils the critical determinant of this expanded genome: the proliferation of repetitive sequences recently inserted, contributing to its enlarged size. The landscape of whole genome collinearity sheds light on the relationships among scallop species, enhancing our broader understanding of their genomic framework. This genome provides genomic resources for future molecular biology research on scallops and serves as a guide for the exploration of longevity-related genes in scallops.


Asunto(s)
Bivalvos , Pectinidae , Animales , Pectinidae/genética , Bivalvos/genética , Alimentos Marinos , Tamaño del Genoma , Cromosomas/genética
17.
BMC Med Educ ; 24(1): 717, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956537

RESUMEN

BACKGROUND: The National Medical Licensing Examination (NMLE) is the only objective, standardized metric to evaluate whether a medical student possessing the professional knowledge and skills necessary to work as a physician. However, the overall pass rate of NMLE in our hospital in 2021 was much lower than that of Peking Union Medical College Hospital, which was required to be further improved. METHODS: To find the reasons for the unsatisfactory performance in 2021, the quality improvement team (QIT) organized regular face-to-face meetings for in-depth discussion and questionnaire, and analyzed the data by "Plato analysis" and "Brainstorming method". After finding out the reasons, the "Plan-Do-Check-Action" (PDCA) cycle was continued to identify and solve problems, which included the formulation and implementation of specific training plans by creating the "Gantt charts", the check of effects, and continuous improvements from 2021 to 2022. Detailed information about the performance of students in 2021 and 2022, and the attendance, assessment, evaluation and suggestions from our hospital were provided by the relevant departments, and the pass rate-associated data was collected online. RESULTS: After the PDCA plan, the pass rate of NMLE in our hospital increased by 10.89% from 80.15% in 2021 to 91.04% in 2022 (P = 0.0109), with the pass rate of skill examination from 95.59% in 2021 to 99.25% in 2022 (P = 0.0581) and theoretical examination from 84.5% in 2021 to 93.13% in 2022 (P = 0.027). Additionally, the mean scores of all examinees increased with the theoretical examination score increasing from 377.0 ± 98.76 in 2021 to 407.6 ± 71.94 in 2022 (P = 0.004). CONCLUSIONS: Our results showed a success application of the PDCA plan in our hospital which improved the pass rate of the NMLE in 2022, and the PDCA plan may provide a practical framework for future medical education and further improve the pass rate of NMLE in the next year.


Asunto(s)
Competencia Clínica , Evaluación Educacional , Licencia Médica , Estudiantes de Medicina , Humanos , Licencia Médica/normas , Competencia Clínica/normas , Mejoramiento de la Calidad , China , Educación de Pregrado en Medicina/normas , Encuestas y Cuestionarios
18.
J Environ Manage ; 365: 121592, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38963959

RESUMEN

Methane, either as natural gas or as a resource obtained from various bioprocesses (e.g., digestion, landfill) can be converted to carbon and hydrogen according to. CH4(g)→C(s)+2H2(g)ΔH298K=74.8kJ/mol. Previous research has stressed the growing importance of substituting the high-temperature Steam Methane Reforming (SMR) by a moderate temperature Catalytic Methane Decomposition (CMD). The carbon formed is moreover of nanotube nature, in high industrial demand. To avoid the use of an inert support for the active catalyst species, e.g., Al2O3 for Fe, leading to a progressive contamination of the catalyst by support debris and coking of the catalyst, the present research investigates the use of carbon nanotubes (CNTs) as Fe-support. Average CH4 conversions of 75-85% are obtained at 700 °C for a continuous operation of 40 h. The produced CNT from the methane conversion can be continuously removed from the catalyst bed by carry-over due to its bulk density difference (∼120 kg/m3) with the catalyst itself (∼1500 kg/m3). CNT properties are fully specified. No thermal regeneration of the catalyst is required. A tentative process layout and economic analysis demonstrate the scalability of the process and the very competitive production costs of H2 and CNT.


Asunto(s)
Hierro , Metano , Nanotubos de Carbono , Metano/química , Nanotubos de Carbono/química , Catálisis , Hierro/química , Hidrógeno/química , Temperatura
19.
Physiol Mol Biol Plants ; 30(8): 1313-1328, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39184561

RESUMEN

Fagopyrum tataricum, an important medicinal and edible crop, possesses significant agricultural and economic value. However, the development of buckwheat varieties and yields has been hindered by the delayed breeding progress despite the abundant material resources in China. Current research indicates that quantitative trait loci (QTLs) play a crucial role in controlling plant seed type and yield. To address these limitations, this study constructed recombinant inbred lines (RILs) utilizing both cultivated species and wild buckwheat as raw materials. In total, 84,521 Single Nucleotide Polymorphism (SNP) markers were identified through Genotyping-by-Sequencing (GBS) technology, and high-resolution and high-density SNP genetic maps were developed, which had significant value for QTL mapping, gene cloning and comparative mapping of buckwheat. In this study, we successfully identified 5 QTLs related to thousand grain weight (TGW), 9 for grain length (GL), and 1 for grain width (GW) by combining seed type and TGW data from 202 RIL populations in four different environments, within which one co-located QTL for TGW were discovered on the first chromosome. Transcriptome analysis during different grain development stages revealed 59 significant expression differences between the two materials, which can serve as candidate genes for further investigation into the regulation of grain weight and yield enhancement. The mapped major loci controlling TGW, GL and GW will be valuable for gene cloning and reveal the mechanism underlying grain development and marker-assisted selection in Tartary buckwheat.

20.
J Am Chem Soc ; 145(27): 14705-14715, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37358565

RESUMEN

Mechanistic investigations of the Ni-catalyzed asymmetric reductive alkenylation of N-hydroxyphthalimide (NHP) esters and benzylic chlorides are reported. Investigations of the redox properties of the Ni-bis(oxazoline) catalyst, the reaction kinetics, and mode of electrophile activation show divergent mechanisms for these two related transformations. Notably, the mechanism of C(sp3) activation changes from a Ni-mediated process when benzyl chlorides and Mn0 are used to a reductant-mediated process that is gated by a Lewis acid when NHP esters and tetrakis(dimethylamino)ethylene is used. Kinetic experiments show that changing the identity of the Lewis acid can be used to tune the rate of NHP ester reduction. Spectroscopic studies support a NiII-alkenyl oxidative addition complex as the catalyst resting state. DFT calculations suggest an enantiodetermining radical capture step and elucidate the origin of enantioinduction for this Ni-BOX catalyst.

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