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1.
J Biol Chem ; 300(3): 105741, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38340793

RESUMEN

Type VI secretion systems (T6SS) are bacterial macromolecular complexes that secrete effectors into target cells or the extracellular environment, leading to the demise of adjacent cells and providing a survival advantage. Although studies have shown that the T6SS in Pseudomonas aeruginosa is regulated by the Quorum Sensing system and second messenger c-di-GMP, the underlying molecular mechanism remains largely unknown. In this study, we discovered that the c-di-GMP-binding adaptor protein PA0012 has a repressive effect on the expression of the T6SS HSI-I genes in P. aeruginosa PAO1. To probe the mechanism by which PA0012 (renamed TssZ, Type Six Secretion System -associated PilZ protein) regulates the expression of HSI-I genes, we conducted yeast two-hybrid screening and identified HinK, a LasR-type transcriptional regulator, as the binding partner of TssZ. The protein-protein interaction between HinK and TssZ was confirmed through co-immunoprecipitation assays. Further analysis suggested that the HinK-TssZ interaction was weakened at high c-di-GMP concentrations, contrary to the current paradigm wherein c-di-GMP enhances the interaction between PilZ proteins and their partners. Electrophoretic mobility shift assays revealed that the non-c-di-GMP-binding mutant TssZR5A/R9A interacts directly with HinK and prevents it from binding to the promoter of the quorum-sensing regulator pqsR. The functional connection between TssZ and HinK is further supported by observations that TssZ and HinK impact the swarming motility, pyocyanin production, and T6SS-mediated bacterial killing activity of P. aeruginosa in a PqsR-dependent manner. Together, these results unveil a novel regulatory mechanism wherein TssZ functions as an inhibitor that interacts with HinK to control gene expression.


Asunto(s)
Proteínas Bacterianas , Regulación Bacteriana de la Expresión Génica , Pseudomonas aeruginosa , Transcripción Genética , Sistemas de Secreción Tipo VI , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , Ensayo de Cambio de Movilidad Electroforética , Inmunoprecipitación , Mutación , Regiones Promotoras Genéticas , Unión Proteica , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Piocianina/metabolismo , Percepción de Quorum , Sistemas de Mensajero Secundario , Técnicas del Sistema de Dos Híbridos , Sistemas de Secreción Tipo VI/genética , Sistemas de Secreción Tipo VI/metabolismo
2.
Chembiochem ; 25(1): e202300590, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-37908177

RESUMEN

Octacosamicin A is an antifungal metabolite featuring a linear polyene-polyol chain flanked by N-hydroxyguanidine and glycine moieties. We report here that sub-inhibitory concentrations of streptomycin elicited the production of octacosamicin A in Amycolatopsis azurea DSM 43854T . We identified the biosynthetic gene cluster (oca BGC) that encodes a modular polyketide synthase (PKS) system for assembling the polyene-polyol chain of octacosamicin A. Our analysis suggested that the N-hydroxyguanidine unit originates from a 4-guanidinobutyryl-CoA starter unit, while the PKS incorporates an α-hydroxyketone moiety using a (2R)-hydroxymalonyl-CoA extender unit. The modular PKS system contains a non-canonical terminal module that lacks thioesterase (TE) and acyl carrier protein (ACP) domains, indicating the biosynthesis is likely to employ an unconventional and cryptic off-loading mechanism that attaches glycine to the polyene-polyol chain via an intermolecular amidation reaction.


Asunto(s)
Glicina , Sintasas Poliquetidas , Sintasas Poliquetidas/genética , Sintasas Poliquetidas/metabolismo , Polienos
3.
Environ Res ; 252(Pt 3): 118941, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38649015

RESUMEN

The Zn/Zr-MOFs were synthesized via microwave-assisted ball milling and subsequently characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The thermal stability of the Zn/Zr-MOFs was evaluated through thermogravimetry (TGA). The results demonstrated the exceptional adsorption properties of the Zn/Zr-MOFs towards Lomefloxacin hydrochloride and Levofloxacin hydrochloride. At a concentration of 30 ppm for Lomefloxacin hydrochloride, the addition of 30 mg of Zn/Zr-MOFs material resulted in an adsorption capacity of 179.2 mg•g-1. Similarly, at a concentration of 40 ppm for Levofloxacin hydrochloride, the addition of 30 mg Zn/Zr-MOFs material led to an adsorption capacity of 187.1 mg•g-1. Kinetic analysis revealed that the experimental data aligned well with a pseudo-second order kinetic model. Overall, these findings highlight the significant potential application of Zn/Zr-MOF materials in wastewater treatment.


Asunto(s)
Fluoroquinolonas , Levofloxacino , Microondas , Aguas Residuales , Contaminantes Químicos del Agua , Zinc , Levofloxacino/química , Adsorción , Fluoroquinolonas/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Zinc/química , Aguas Residuales/química , Circonio/química , Antibacterianos/química , Cinética , Estructuras Metalorgánicas/química
4.
Genes Immun ; 24(3): 124-129, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37156995

RESUMEN

Heat shock protein family A (Hsp70) member 5 (HSPA5) is an endoplasmic reticulum chaperone, which regulates cell metabolism, particularly lipid metabolism. While HSPA5's role in regulating cell function is well described, HSPA5 binding to RNA and its biological function in nonalcoholic fatty liver disease (NAFLD) is still lacking. In the present study, the ability of HSPA5 to modulate alternative splicing (AS) of cellular genes was assessed using Real-Time PCR on 89 NAFLD-associated genes. RNA immunoprecipitation coupled to RNA sequencing (RIP-Seq) assays were also performed to identify cellular mRNAs bound by HSPA5. We obtained the HSPA5-bound RNA profile in HeLa cells and peak calling analysis revealed that HSPA5 binds to coding genes and lncRNAs. Moreover, RIP-Seq assays demonstrated that HSPA5 immunoprecipitates specific cellular mRNAs such as EGFR, NEAT1, LRP1 and TGFß1, which are important in the pathology of NAFLD. Finally, HSPA5 binding sites may be associated with splicing sites. We used the HOMER algorithm to search for motifs enriched in coding sequence (CDs) peaks, which identified over-representation of the AGAG motif in both sets of immunoprecipitated peaks. HSPA5 regulated genes at the 5'UTR alternative splicing and introns and in an AG-rich sequence-dependent manner. We propose that the HSPA5-AGAG interaction might play an important role in regulating alternative splicing of NAFLD-related genes. This report is the first to demonstrate that HSPA5 regulated pre-RNA alternative splicing, stability, or translation and affected target protein(s) via binding to lncRNA and mRNA linked to NAFLD.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/genética , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/metabolismo , Células HeLa , Chaperón BiP del Retículo Endoplásmico , ARN Mensajero/genética
5.
Cancer Cell Int ; 23(1): 151, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37525152

RESUMEN

BACKGROUND: Exosome, a component of liquid biopsy, loaded protein, DNA, RNA and lipid gradually emerges as biomarker in tumors. However, exosomal circRNAs as biomarker and function mechanism in gastric cancer (GC) are not well understood. METHODS: Differentially expressed circRNAs in GC and healthy people were screened by database. The identification of hsa_circ_000200 was verified by RNase R and sequencing, and the expression of hsa_circ_000200 was evaluated using qRT-PCR. The biological function of hsa_circ_000200 in GC was verified in vitro. Western blot, RIP, RNA fluorescence in situ hybridization, and double luciferase assay were utilized to explore the potential mechanism of hsa_circ_000200. RESULTS: Hsa_circ_000200 up-regulated in GC tissue, serum and serum exosomes. Hsa_circ_000200 in serum exosomes showed better diagnostic ability than that of tissues and serum. Combined with clinicopathological parameters, its level was related to invasion depth, TNM staging, and distal metastasis. Functionally, knockdown of hsa_circ_000200 inhibited GC cells proliferation, migration and invasion in vitro, while its overexpression played the opposite role. Importantly, exosomes with up-regulated hsa_circ_000200 promoted the proliferation and migration of co-cultured GC cells. Mechanistically, hsa_circ_000200 acted as a "ceRNA" for miR-4659a/b-3p to increase HBEGF and TGF-ß/Smad expression, then promoted the development of GC. CONCLUSIONS: Our findings suggest that hsa_circ_000200 promotes the progression of GC through hsa_circ_000200/miR-4659a/b-3p/HBEGF axis and affecting the expression of TGF-ß/Smad. Serum exosomal hsa_circ_000200 may serve as a potential biomarker for GC.

6.
Theor Appl Genet ; 136(10): 212, 2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37740151

RESUMEN

KEY MESSAGE: GmTSA and GmALS were screened out for salt stress in soybean and explore the poteintial amino acid secondary metabolism pathways. Soybean (Glycine max L.) is an oil and protein crop of global importance, and salinity has significant effects on soybean growth. Here, a population of soybean chromosome segment substitution lines was screened to identify highly salt-tolerant lines. In total, 24 quantitative trait loci (QTLs) on seven chromosomes were associated with salt tolerance, and CSSL_R71 was selected for further analysis. Although numerous genes were differentially expressed in CSSL_R71 in response to salt statically no differently, transcript levels of classical salt-response genes, including those of the salt overly sensitive pathway. Rather, salt tolerance in CSSL_R71 was associated with changes in amino acid and lipid metabolism. In particular, changes in p-coumaric acid, shikimic acid, and pyrrole-2-carboxylic acid levels accompanied salt tolerance in CSSL_R71. Eleven differentially expressed genes (DEGs) related to amino acid and secondary metabolism were identified as candidate genes on the substituted chromosome fragment. Six of these showed differences in coding sequence between the parental genotypes. Crucially, overexpression of GmTSA (Glyma.03G158400, tryptophan synthase) significantly enhanced salt tolerance in soybean hairy roots, whereas overexpression of GmALS (Glyma.13G241000, acetolactate synthase) decreased salt tolerance. Two KASP markers were developed for GmALS and used to genotype salt-tolerant and salt-sensitive lines in the CSSL population. Non-synonymous mutations were directly associated with salt tolerance. Taken together, these data provide evidence that changes in amino acid and secondary metabolism have the potential to confer salt tolerance in soybean.


Asunto(s)
Aminoácidos , Glycine max , Metabolismo Secundario , Glycine max/genética , Tolerancia a la Sal/genética , Estrés Salino
7.
Langmuir ; 39(1): 647-658, 2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36563178

RESUMEN

Rapid chemical functionalization of additives and efficient determination of their optimum concentrations are important for designing high-performance lubricants, especially under multi-additive conditions. Herein, chemically functionalized graphene (FGR) and carbon nanotubes (FCNTs) were rapidly prepared by microwave-assisted ball milling and subsequently introduced into grease as additives. The tribological properties of the additives in grease at different concentrations and ratios were measured using a four-ball test. A reliable artificial neural network (ANN) model was established according to a few test results. Subsequently, the optimal concentration of multiple additives in the grease was predicted using a genetic algorithm and experimentally validated. The results indicated that the introduction of FGR (0.14 wt %) and FCNT (0.16 wt %) improved the antifriction and anti-wear performance of the base grease by 25.66 and 29.34%, respectively. The results of the ANN model analysis and friction interface characterization indicate that such performance is principally attributed to the synergistic lubrication of the FGR and FCNT.

8.
Molecules ; 28(11)2023 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-37298886

RESUMEN

This work studies the use of Fe/Ni-MOFs for the removal of ciprofloxacin (CIP) in wastewater. Fe/Ni-MOFs are prepared by the solvothermal method and characterized by X-ray diffraction (XRD), a scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), and a thermal gravimetric analyzer (TG). Under the conditions of the concentration of 50 ppm, a mass of 30 mg, and a temperature of 30 °C, the maximum adsorption capacity of ciprofloxacin removal within 5 h was 232.1 mg/g. The maximum removal rate was 94.8% when 40 mg of the Fe/Ni-MOFs was added to the solution of 10 ppm ciprofloxacin. According to the pseudo-second-order (PSO) kinetic model, the R2 values were all greater than 0.99, which proved that the adsorption theory of ciprofloxacin by Fe/Ni-MOFs was consistent with the practice. The adsorption results were mainly affected by solution pH and static electricity, as well as other factors. The Freundlich isotherm model characterized the adsorption of ciprofloxacin by Fe/Ni-MOFs as multilayer adsorption. The above results indicated that Fe/Ni-MOFs were effective in the practical application of ciprofloxacin removal.


Asunto(s)
Ciprofloxacina , Contaminantes Químicos del Agua , Ciprofloxacina/química , Aguas Residuales , Adsorción , Espectroscopía Infrarroja por Transformada de Fourier , Contaminantes Químicos del Agua/química , Cinética , Concentración de Iones de Hidrógeno
9.
Genes Immun ; 23(8): 246-254, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35941292

RESUMEN

RALY is a multifunctional RNA-binding protein involved in cancer metastasis, prognosis, and chemotherapy resistance in various cancers. However, the molecular mechanism of which is still unclear. We have established RALY overexpression cell lines and studied the effect of RALY on proliferation and apoptosis in HeLa cells. Then we used RNA-seq to analyze the transcriptomes data. Lastly, RT-qPCR experiments had performed to confirm the RNA-seq results. We found that the overexpression of RALY in HeLa cells inhibited proliferation. Moreover, the overexpression of RALY changed the gene expression profile, and the significant upregulation of genes involved immune/inflammatory response related biological process by NOD-like receptor signaling pathway cytokine-cytokine receptor interaction. The significant downregulation genes involved innate immune response by the Primary immunodeficiency pathway. Notably, IFIT1, IFIT2, IFTI3, IFI44, HERC4, and OASL expression had inhibited by the overexpression of RALY. Furthermore, RALY negatively regulates the expression of transcription factors FOS and FOSB. Notably, we found that 645 alternative splicing events had regulated by overexpression of RALY, which is highly enriched in transcription regulation, RNA splicing, and cell proliferation biological process by the metabolic pathway. We show that RALY regulates the expression of immune/inflammatory response-related genes via alternative splicing of FOS in HeLa cells. The novel role of RALY in regulating immune/inflammatory gene expression may explain its function in regulating chemotherapy resistance and provides novel insights into further exploring the molecular mechanism of RALY in regulating cancer immunity and chemo/immune therapies.


Asunto(s)
Empalme Alternativo , Ribonucleoproteína Heterogénea-Nuclear Grupo C , Humanos , Ribonucleoproteína Heterogénea-Nuclear Grupo C/genética , Ribonucleoproteína Heterogénea-Nuclear Grupo C/metabolismo , Células HeLa , Proliferación Celular , Transcriptoma
10.
J Am Chem Soc ; 144(4): 1622-1633, 2022 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-35060699

RESUMEN

Naturally occurring hydrazones are rare despite the ubiquitous usage of synthetic hydrazones in the preparation of organic compounds and functional materials. In this study, we discovered a family of novel microbial metabolites (tasikamides) that share a unique cyclic pentapeptide scaffold. Surprisingly, tasikamides A-C (1-3) contain a hydrazone group (C═N─N) that joins the cyclic peptide scaffold to an alkyl 5-hydroxylanthranilate (AHA) moiety. We discovered that the biosynthesis of 1-3 requires two discrete gene clusters, with one encoding a nonribosomal peptide synthetase (NRPS) pathway for assembling the cyclic peptide scaffold and another encoding the AHA-synthesizing pathway. The AHA gene cluster encodes three ancillary enzymes that catalyze the diazotization of AHA to yield an aryl diazonium species (diazo-AHA). The electrophilic diazo-AHA undergoes nonenzymatic Japp-Klingemann coupling with a ß-keto aldehyde-containing cyclic peptide precursor to furnish the hydrazone group and yield 1-3. The studies together unraveled a novel mechanism whereby specialized metabolites are formed by the coupling of two biosynthetic pathways via an unprecedented in vivo Japp-Klingemann reaction. The findings raise the prospect of exploiting the arylamine-diazotizing enzymes (AAD) for the in vivo synthesis of aryl compounds and modification of biological macromolecules.


Asunto(s)
Compuestos de Diazonio/química , Hidrazonas/química , Oligopéptidos/biosíntesis , Vías Biosintéticas/genética , Hidrazonas/síntesis química , Familia de Multigenes , Oligopéptidos/química , Péptido Sintasas/genética , Péptido Sintasas/metabolismo , Péptidos Cíclicos/biosíntesis , Péptidos Cíclicos/química , Streptomyces/metabolismo
11.
Chembiochem ; 23(22): e202200457, 2022 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-36161451

RESUMEN

A family of novel cyclic lipopeptides named tasikamides A-H (Tsk A-H) were discovered recently in Streptomyces tasikensis P46. Aside from the unique cyclic pentapeptide scaffold shared by the tasikamides, Tsk A-C contain a hydrazone bridge that connects the cyclic pentapeptide to the lipophilic alkyl 5-hydroxylanthranilate (AHA) moiety. Here we report the production of tasikamides I-K (Tsk I-K) by a mutant strain of S. tasikensis P46 that overexpresses two pathway-specific transcription regulators. Unlike Tsk A-C, Tsk I-K feature a rare enaminone-bridge that links the cyclic peptide scaffold to the AHA moiety. Our experimental data suggest that Tsk I-K are generated by the coupling of two biosynthetic pathways via a nonenzymatic condensation reaction between an arylamine and a ß-keto aldehyde-containing precursor. The results underscore the nucleophilic and electrophilic reactivity of the ß-keto aldehyde moiety and its ability to promote fragment coupling reactions in live microbial cells.


Asunto(s)
Vías Biosintéticas , Streptomyces , Péptidos Cíclicos/metabolismo , Streptomyces/metabolismo , Antibacterianos/metabolismo , Lipopéptidos/metabolismo , Aldehídos/metabolismo , Familia de Multigenes
12.
Appl Environ Microbiol ; 88(23): e0120822, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36350133

RESUMEN

Angucyclines are a family of structurally diverse, aromatic polyketides with some members that exhibit potent bioactivity. Angucyclines have also attracted considerable attention due to the intriguing biosynthetic origins that underlie their structural complexity and diversity. Balmoralmycin (compound 1) represents a unique group of angucyclines that contain an angular benz[α]anthracene tetracyclic system, a characteristic C-glycosidic bond-linked deoxy-sugar (d-olivose), and an unsaturated fatty acid chain. In this study, we identified a Streptomyces strain that produces balmoralmycin and seven biosynthetically related coproducts (compounds 2-8). Four of the coproducts (compounds 5-8) are novel compounds that feature a highly oxygenated or fragmented lactone ring, and three of them (compounds 3-5) exhibited cytotoxicity against the human pancreatic cancer cell line MIA PaCa-2 with IC50 values ranging from 0.9 to 1.2 µg/mL. Genome sequencing and CRISPR/dCas9-assisted gene knockdown led to the identification of the ~43 kb balmoralmycin biosynthetic gene cluster (bal BGC). The bal BGC encodes a type II polyketide synthase (PKS) system for assembling the angucycline aglycone, six enzymes for generating the deoxysugar d-olivose, and a hybrid type II/III PKS system for synthesizing the 2,4-decadienoic acid chain. Based on the genetic and chemical information, we propose a mechanism for the biosynthesis of balmoralmycin and the shunt products. The chemical and genetic studies yielded insights into the biosynthetic origin of the structural diversity of angucyclines. IMPORTANCE Angucyclines are structurally diverse aromatic polyketides that have attracted considerable attention due to their potent bioactivity and intriguing biosynthetic origin. Balmoralmycin is a representative of a small family of angucyclines with unique structural features and an unknown biosynthetic origin. We report a newly isolated Streptomyces strain that produces balmoralmycin in a high fermentation titer as well as several structurally related shunt products. Based on the chemical and genetic information, a biosynthetic pathway that involves a type II polyketide synthase (PKS) system, cyclases/aromatases, oxidoreductases, and other ancillary enzymes was established. The elucidation of the balmoralmycin pathway enriches our understanding of how structural diversity is generated in angucyclines and opens the door for the production of balmoralmycin derivatives via pathway engineering.


Asunto(s)
Policétidos , Streptomyces , Humanos , Vías Biosintéticas/genética , Familia de Multigenes , Sintasas Poliquetidas/genética , Sintasas Poliquetidas/metabolismo , Policétidos/metabolismo , Streptomyces/metabolismo , Línea Celular Tumoral
13.
Crit Rev Food Sci Nutr ; : 1-12, 2022 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-36300845

RESUMEN

Microorganisms in food do harms to human. They can cause serious adverse reactions and sometimes even death. So it is an urgent matter to find an effective method to control them. The research of intelligent- biosensor packaging is in the ascendant in recent years, which is mainly promoted by reflecting on food safety and reducing resource waste. Intelligent biosensor-packaging is an instant and efficient intelligent packaging technology, which can directly and scientifically manifest the quality of food without complex operation. In this review, the purposes of providing relevant information on intelligent biosensor-packaging are reviewed, such as types of biosensors for monitoring foodborne microorganism, the suitable material for intelligent biosensor-packaging and design and fabrication of intelligent biosensor-packaging. The potential of intelligent biosensor-packaging in the detection of foodborne microorganisms is emphasized. The challenges and directions of the intelligent biosensor-packaging in the detection of foodborne pathogens are discussed. With the development of science and technology in the future, the intelligent biosensor-packaging should be commercialized in a real sense. And it is expected that commercial products can be manufactured in the future, which will provide a far-reaching approach in food safety and food prevention. HighlightsSeveral biosensors are suitable for the detection of food microorganisms.Plastic polymer is an excellent choice for the construction of intelligent biosensor packaging.Design and fabrication can lay the foundation for intelligent-biosensor packaging.Intelligent biosensor-packaging can realize fast and real-time detection of microorganisms in food.

14.
Ecotoxicology ; 31(2): 289-298, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34982302

RESUMEN

Potentially toxic elements (PTEs) in lake sediments are concerning because of their toxic effects on lacustrine ecosystems and human health. Baiyangdian Lake (BYDL), the "pearl of North China", plays a vital role in maintaining the ecological health of North China. Here, risk assessment and source identification of nutrients and PTEs in sediments were performed. The results showed that the sediments were highly contaminated with total organic carbon (TOC) and total nitrogen (TN), but contamination by total phosphorus (TP) was minor, and the ecological risk associated with Cd was considerable, especially in the northern region. The average noncarcinogenic hazard quotient of PTEs increased in the order of Zn < Hg < Cd < Cu < Ni < Pb < Cr < As. Statistical analyses indicated that Al, Ti, Fe, Co, Cr, Hg, Ni, and rare earth elements were primarily from natural origins; Pb was derived from local tourism development and pollution by fishermen; and TOC, TN, TP, As, Cd, Cu, Zn, and Mn were mainly derived from industrial and agricultural activities. Additionally, the mean contribution rates of industrial wastewater and domestic sewage sources, agricultural sources, and natural sources to BYDL sediment pollution were 59.9%, 17.9%, and 22.2%, respectively. Spatially, industrial and domestic sewage sources contributed more in the northwestern region (average 79.8%) than in the southern region (average 35.5%), while agricultural sources contributed the most in the southwestern region (average 41.3%). These findings will advance our knowledge of the spatial differences, contamination risks and sources of nutrients and PTEs in BYDL and provide a scientific basis to help policy-makers establish a healthy ecological community in BYDL of the Xiong'an New Area.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , China , Ecosistema , Monitoreo del Ambiente/métodos , Sedimentos Geológicos , Humanos , Lagos , Metales Pesados/análisis , Nutrientes , Medición de Riesgo , Aguas Residuales , Contaminantes Químicos del Agua/análisis
15.
Int J Mol Sci ; 23(15)2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35897765

RESUMEN

The plant parasitic nematode, Aphelenchoides besseyi, is a serious pest causing severe damage to various crop plants and vegetables. The Bacillus thuringiensis (Bt) strains, GBAC46 and NMTD81, and the biological strain, FZB42, showed higher nematicidal activity against A. besseyi, by up to 88.80, 82.65, and 75.87%, respectively, in a 96-well plate experiment. We screened the whole genomes of the selected strains by protein-nucleic acid alignment. It was found that the Bt strain GBAC46 showed three novel crystal proteins, namely, Cry31Aa, Cry73Aa, and Cry40ORF, which likely provide for the safe control of nematodes. The Cry31Aa protein was composed of 802 amino acids with a molecular weight of 90.257 kDa and contained a conserved delta-endotoxin insecticidal domain. The Cry31Aa exhibited significant nematicidal activity against A. besseyi with a lethal concentration (LC50) value of 131.80 µg/mL. Furthermore, the results of in vitro experiments (i.e., rhodamine and propidium iodide (PI) experiments) revealed that the Cry31Aa protein was taken up by A. besseyi, which caused damage to the nematode's intestinal cell membrane, indicating that the Cry31Aa produced a pore-formation toxin. In pot experiments, the selected strains GBAC46, NMTD81, and FZB42 significantly reduced the lesions on leaves by up to 33.56%, 45.66, and 30.34% and also enhanced physiological growth parameters such as root length (65.10, 50.65, and 55.60%), shoot length (68.10, 55.60, and 59.45%), and plant fresh weight (60.71, 56.45, and 55.65%), respectively. The number of nematodes obtained from the plants treated with the selected strains (i.e., GBAC46, NMTD81, and FZB42) and A. besseyi was significantly reduced, with 0.56, 0.83., 1.11, and 5.04 seedling mL-1 nematodes were achieved, respectively. Moreover, the qRT-PCR analysis showed that the defense-related genes were upregulated, and the activity of hydrogen peroxide (H2O2) increased while malondialdehyde (MDA) decreased in rice leaves compared to the control. Therefore, it was concluded that the Bt strains GBAC46 and NMTD81 can promote rice growth, induce high expression of rice defense-related genes, and activate systemic resistance in rice. More importantly, the application of the novel Cry31Aa protein has high potential for the efficient and safe prevention and green control of plant parasitic nematodes.


Asunto(s)
Bacillus thuringiensis , Oryza , Rabdítidos , Tylenchida , Animales , Antinematodos/metabolismo , Antinematodos/farmacología , Bacillus thuringiensis/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/farmacología , Peróxido de Hidrógeno/metabolismo , Oryza/metabolismo , Plantas/metabolismo , Rabdítidos/metabolismo , Tylenchida/metabolismo
16.
J Am Chem Soc ; 143(30): 11500-11509, 2021 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-34293863

RESUMEN

Anthraquinone-fused enediynes (AQEs) are renowned for their distinctive molecular architecture, reactive enediyne warhead, and potent anticancer activity. Although the first members of AQEs, i.e., dynemicins, were discovered three decades ago, how their nitrogen-containing carbon skeleton is synthesized by microbial producers remains largely a mystery. In this study, we showed that the recently discovered sungeidine pathway is a "degenerative" AQE pathway that contains upstream enzymes for AQE biosynthesis. Retrofitting the sungeidine pathway with genes from the dynemicin pathway not only restored the biosynthesis of the AQE skeleton but also produced a series of novel compounds likely as the cycloaromatized derivatives of chemically unstable biosynthetic intermediates. The results suggest a cascade of highly surprising biosynthetic steps leading to the formation of the anthraquinone moiety, the hallmark C8-C9 linkage via alkyl-aryl cross-coupling, and the characteristic epoxide functionality. The findings provide unprecedented insights into the biosynthesis of AQEs and pave the way for examining these intriguing biosynthetic enzymes.

17.
Small ; 17(36): e2102307, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34270871

RESUMEN

The development of efficient visible-light-driven photocatalysts is one of the critically important issues for solar hydrogen production. Herein, high-efficiency visible-light-driven In2 O3 /CdZnS hybrid photocatalysts are explored by a facile oil-bath method, in which ultrafine CdZnS nanoparticles are anchored on NH2 -MIL-68-derived fusiform In2 O3 mesoporous nanorods. It is disclosed that the as-prepared In2 O3 /CdZnS hybrid photocatalysts exhibit enhanced visible-light harvesting, improves charges transfer and separation as well as abundant active sites. Correspondingly, their visible-light-driven H2 production rate is significantly enhanced for more than 185 times to that of pristine In2 O3 nanorods, and superior to most of In2 O3 -based photocatalysts ever reported, representing their promising applications in advanced photocatalysts.


Asunto(s)
Nanopartículas , Nanotubos , Hidrógeno , Luz
18.
Br J Surg ; 108(9): 1126-1132, 2021 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-34037206

RESUMEN

BACKGROUND: This study aims to assess the learning curve of robotic distal gastrectomy (RDG) and robotic total gastrectomy (RTG) for gastric cancer. METHODS: Data on consecutive patients who underwent robotic gastrectomy for gastric cancer by five surgeons between March 2010 and August 2019 at two high-volume institutions were collected. The learning curve was determined based on the analyses of operation time and postoperative complications within 30 days. Cumulative sum analysis (CUSUM) and risk-adjusted-CUSUM (RA-CUSUM) were applied to identify the turning points (TPs). RESULTS: A total of 899 consecutive patients were included. The mean number of patients needed to overcome the learning curve for operation time of RDG and RTG were 22 and 20, respectively. The number of patients needed to overcome the learning curve for postoperative complications after RDG and RTG were 23 and 18, respectively. The surgical outcomes in the post-TP group were better than in the pre-TP group and improved as surgeons' experience increased. Also, increased case numbers in RDG promoted the RTG learning process. CONCLUSION: The present study demonstrated a substantial influence of surgical cumulative volume on improved surgical outcomes in robotic gastrectomy. Increased experience in RDG may help surgeons to achieve proficiency faster in RTG.


Asunto(s)
Gastrectomía/métodos , Laparoscopía/métodos , Curva de Aprendizaje , Procedimientos Quirúrgicos Robotizados/métodos , Neoplasias Gástricas/cirugía , Humanos , Tempo Operativo , Estudios Retrospectivos
19.
Surg Endosc ; 35(7): 3572-3583, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-32780230

RESUMEN

BACKGROUND: Robotic distal gastrectomy (RDG) has been increasingly used for the treatment of gastric cancer in recent year. However, whether RDG could reduce the morbidity when compared to laparoscopic distal gastrectomy (LDG) remains controversial. This study aimed to compare the morbidity and short-term surgical outcomes of RDG and LDG for gastric cancer and identify the related risk factors. METHODS: Between March 2010 and August 2019, consecutive patients undergoing RDG or LDG (519 and 957 patients, respectively) at our institution were included in this study. Postoperative complications were stratified according to the Clavien-Dindo (C-D) classification. We performed one-to-one propensity score matching (PSM) analysis, and evaluated postoperative morbidity and short-term surgical outcomes in PSM 1032 patients undergoing RDG or LDG. RESULTS: After PSM, the two groups were well-balanced. The mean blood loss of the RDG group was about 27 mL less than that of the LDG group (112.1 vs 139.0 mL, P < 0.001). The RDG group had more retrieved lymph nodes than that in the LDG group (32.7 v 30.2, P < 0.001). The RDG group showed a similar overall (9.9% vs 10.7%, P = 0.682), severe (2.7% vs 3.7%, P = 0.376), local (5.6% vs 5.2%, P = 0.783), and systemic complication rates (5.4% vs 6.0%, P = 0.688). There were no significant differences in mortality between the two groups (RDG 0% vs LDG 0.2%, P = 1.000). Subgroup analyses showed no significant differences in most stratified parameters. Age > 65 years and ASA III were identified as two major risk factors for complications. CONCLUSION: RDG could be a safe and feasible in treating gastric cancer compared to LDG. However, we did not observe significant reduction in postoperative complications of RDG compared with LDG, although the use of robotic system is assumed to provide a technically superior operative environment.


Asunto(s)
Laparoscopía , Procedimientos Quirúrgicos Robotizados , Neoplasias Gástricas , Estudios de Cohortes , Gastrectomía/efectos adversos , Humanos , Recién Nacido , Morbilidad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Procedimientos Quirúrgicos Robotizados/efectos adversos , Neoplasias Gástricas/cirugía , Resultado del Tratamiento
20.
J Clin Periodontol ; 48(8): 1137-1148, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33998036

RESUMEN

AIM: To characterize gingival metabolome in high-fat diet (HFD)-induced obesity in mice with/without periodontitis. METHODS: HFD-induced obesity mouse model was established by 16-week feeding, and a lean control group was fed with low-fat diet (n = 21/group). Both models were induced for periodontitis on the left sides by molar ligation for 10 days, whereas the right sides were used as controls. Gingival metabolome and arginine metabolism were analysed by non-targeted/targeted liquid chromatography-mass spectrometry. RESULTS: Of 2247 reference features, presence of periodontitis altered 165 in lean versus 885 in HFD mice; and HFD altered 525 in absence versus 1435 in presence of periodontitis. Compared with healthy condition, periodontitis and HFD had distinct effects on gingival metabolome. Metabolomic impacts of periodontitis were generally greater in HFD mice versus lean controls. K-medoids clustering showed that HFD amplified the impacts of periodontitis on gingival metabolome in both intensity and extensity. Ten metabolic pathways were enriched, including 2 specific to periodontitis, 5 specific to HFD and 3 shared ones. Targeted validation on arginine metabolism confirmed the additive effects between HFD and periodontitis. CONCLUSION: The obese population consuming excessive HFD display amplified metabolic response to periodontitis, presenting a metabolic susceptibility to exacerbated periodontal destruction.


Asunto(s)
Dieta Alta en Grasa , Periodontitis , Animales , Dieta Alta en Grasa/efectos adversos , Metaboloma , Ratones , Ratones Endogámicos C57BL , Obesidad/complicaciones , Periodontitis/etiología , Roedores
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