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The conversion of CO2 into valuable solar fuels via photocatalysis is a promising strategy for addressing energy shortages and environmental crises. Here, novel In2 O3 @Co2 VO4 hierarchical heterostructures are fabricated by in situ growing Co2 VO4 nanorods onto In2 O3 nanofibers. First-principle calculations and X-ray photoelectron spectroscopy (XPS) measurements reveal the electron transfer between In2 O3 and Co2 VO4 driven by the difference in work functions, thus creating an interfacial electric field and bending the bands at the interfaces. In this case, the photogenerated electrons in In2 O3 transport to Co2 VO4 and recombine with its holes, indicating the formation of In2 O3 @Co2 VO4 S-scheme heterojunctions and resulting in effective separation of charge carriers, as confirmed by in situ irradiation XPS. The unique S-scheme mechanism, along with the enhanced optical absorption and the lower Gibbs free energy change for the production of * CHO, significantly contributes to the efficient CO2 photoreduction into CO and CH4 in the absence of any molecule cocatalyst or scavenger. Density functional theory simulation and in situ diffuse reflectance infrared Fourier transform spectroscopy are employed to elucidate the reaction mechanism in detail.
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Aqueous copper metal batteries with acidic electrolytes are regarded as promising candidates for low-temperature energy storage, benefiting from fast kinetics of protons and acid resistance of copper. Here, a Cu(BF4 )2 electrolyte that spontaneously generates protons is developed for ultralow-temperature copper metal batteries. Systematic studies demonstrate that the hydrolysis of BF4 - generates more protons, rendering the Cu(BF4 )2 among the most effective aqueous electrolyte capable of breaking hydrogen bonds in water molecules. This electrolyte endows a polyaniline/Cu battery to deliver a short charging time of 21â s and a charge/discharge capability of up to 10â A g-1 at -30 °C, along with a high discharge specific capacity of 70â mAh g-1 and a supercapacitor-comparable power density of 3000â W kg-1 . Furthermore, it can exhibit a long and stable cycling lifespan over 10 000â cycles at -50 °C and works well at -70 °C. This work provides an opportunity for intrinsically acidic electrolytes.
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Photodetectors are critical components in intelligent optoelectronic systems, and photomultiplication-capable devices are essential for detecting weak optical signals. Despite significant advances, developing photomultiplication-type organic photodetectors with high gain and low noise current simultaneously remains challenging. In this work, a new conjugated polymer PDN with singlet open-shell ground state is introduced in active layers for electron capture, and the corresponding PDN-based photodetectors exhibited an enhanced photoelectric gain and decreased dark current density at a low forward bias. At 1.5â V, the PDN-based ternary photodetector has the external quantum efficiency (EQE) up to 2552.3 % and the specific detectivity of 1.4×1014 â Jones at 710â nm calculated by the measured noise current, with the gain 22â times higher than that of the control group. This study provides an approach for exploiting polymers with singlet open-shell ground state to enhance the gain of organic photodetectors.
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Bupleuri Radix, serving as the sovereign medicinal in many antidepressant compound preparations, has been proved effective in treating depression in mice, but its effect on the intestinal flora remains unclear. The present study aimed to investigate the effects of Bupleurum chinense(one of the original materials of Bupleuri Radix) on the behaviors and the diversity of intestinal flora of depressed mice. A depression mouse model was induced by repeated social defeat stress. Specifically, C57 BL/6 J male mice were exposed to the attack from the CD-1 mice. Then, C57 BL/6 J male mice were divided into a depression group and a B. chinense group, with normal saline and B. chinense administered(ig) respectively. Sucrose preference test and tail suspension test were conducted during and after the experiment respectively, to analyze the effects of B. chinense on the behaviors of the depressed mice. The feces were collected after the experiment. The V3-V4 16 S rDNA regions of intestinal flora of mice in each group were sequenced by Ion S5 TMXL for the analysis of the number of operational taxonomic units(OTUs), richness, alpha and beta diversity indexes, and differential phyla and genera. The results indicated that B. chinense could decrease depressive-like behaviors of mice, increase sucrose preference, and shorten the time of immobility in tail suspension test. After B. chinense intervention, the relative abundance of Firmicutes was significantly decreased, while that of Bacteroidetes was increased at the phylum level. At the genus level, the relative abundance of Lactobacillus and Lachnoclostridium decreased(P<0.05), while that of Bacteroides, Alistopes, etc. was elevated(P<0.05). The findings demonstrate that B. chinense can regulate the intestinal flora and improve the depressive-like behaviors of mice with depression.
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Bupleurum , Microbioma Gastrointestinal , Animales , Heces , Lactobacillus , Ratones , Ratones Endogámicos C57BLRESUMEN
BACKGROUND: New strategies are urgently needed to deal with the growing problem of multidrug-resistant bacterial pathogens. As the natural viruses against bacteria, recently, bacteriophages have received particular attention. Here, we identified and characterized a novel peptidoglycan hydrolase named MMPphg by decoding the complete genome sequence of Meiothermus bacteriophage MMP17, which was isolated in Tengchong hot spring in China and contains a circular genome of 33,172 bp in size and a GC content of 63.4%. FINDINGS: We cloned the MMPphg gene, overproduced and purified the phage lytic protein, which contains a highly conserved M23 metallopeptidase domain and can be activated by Mg2+ and Zn2+. MMPphg is capable of withstanding temperatures up to 70 °C, and preserved more than 80% of its activity after a 30 min treatment between 35 and 65 °C. More interestingly, by disrupting bacterial cells, MMPphg exhibits surprising antimicrobial activity against both Gram-negative and Gram-positive pathogenic bacteria, especially antibiotic-resistant strains such as Escherichia coli O157, Staphylococcus aureus and Klebsiella pneumonia. CONCLUSIONS: In the current age of mounting antibiotic resistance, these results suggest the great potential of MMPphg, the gene product of bacteriophage MMP17, in combating bacterial infections and shed light on bacteriophage-based strategies to develop alternatives to conventional antibiotics for human or veterinary applications.
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Antiinfecciosos/farmacología , Bacteriófagos/enzimología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , N-Acetil Muramoil-L-Alanina Amidasa/farmacología , Bacteriófagos/genética , China , ADN Viral/genética , Farmacorresistencia Bacteriana , Estabilidad de Enzimas , Calor , Metaloproteasas/metabolismo , N-Acetil Muramoil-L-Alanina Amidasa/aislamiento & purificación , Secuenciación Completa del GenomaRESUMEN
Recently, high cell-density (HCD) cultivation has become an important tool for production of many microbial products. However, to the best of our knowledge, no study regarding HCD fermentation, overproduction and purification of thermostable bacteriophage lysin has been reported. Here, by employing a glucose-limited fed-batch strategy, we performed high density fermentation of the host Escherichia coli BL21(DE3) cells, compared the efficiency of high pressure homogenization, ultrasonication and thermolysis in bacterial cell disruption after HCD cultivation, and purified TSPphg, a thermostable lysin derived from extremophilic bacteriophage TSP4. On the 20-L scale, the overproduction level of TSPphg was up to 67.8 ± 0.7%. In total, we obtained a broth titer of 3322.8 ± 26 mg/L TSPphg with a purity of 95.5 ± 0.7% from a bacterial cell mass of 86.3 ± 4.9 g/L after 26 h of fermentation. The overall productivity of TSPphg was 127.8 ± 1 mg/L/h. Additionally, the antimicrobial activity of purified TSPphg against both Gram-negative (Escherichia coli O157) and Gram-positive (Staphylococcus aureus) pathogenic bacteria was further confirmed by scanning electron microscope analysis. Summarily, for the first time, we have established a relatively stable and efficient HCD cultivation and purification process for recovery of thermostable lysins from extremophilic Thermus bacteriophages. Our results provide insights into the strategies for time-saving and cost-effective production of antimicrobial proteins to replace or supplement antibiotics in the current age of mounting antibiotic resistance.
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Antiinfecciosos , Bacteriófagos , Endopeptidasas , Siphoviridae , Thermus/virología , Proteínas Virales , Antiinfecciosos/química , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Bacteriófagos/enzimología , Bacteriófagos/genética , Endopeptidasas/biosíntesis , Endopeptidasas/genética , Endopeptidasas/aislamiento & purificación , Endopeptidasas/farmacología , Escherichia coli/enzimología , Escherichia coli/genética , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/farmacología , Siphoviridae/enzimología , Siphoviridae/genética , Proteínas Virales/biosíntesis , Proteínas Virales/genética , Proteínas Virales/aislamiento & purificación , Proteínas Virales/farmacologíaRESUMEN
Amphioxus is a key model for studying comparative immunity of vertebrates. Circular RNA (circRNA), as RNAs with a circular structure, has received little attention until recently, where several studies have reported that circRNA expression changes are involved in the immune response in animals. However, circRNA and its immune role in amphioxus have not been previously studied. Here, circRNAs in Chinese amphioxus (Branchiostoma belcheri) were sequenced, and 1859 circRNAs were identified using two algorithms (find_circ and CIRI). The analysis of miRNA target sites on circRNAs showed that 332 circRNAs may function as miRNA sponges. Furthermore, we identified circRNAs that were conserved between B. belcheri and vertebrates, tracing the origin of these circRNAs within chordates. Additionally, in combination with several key antiviral immune (poly(I:C), pIC) pathways identified in our previous B. belcheri studies, nine circRNAs potentially involved in these pathways were identified using bioinformatic predictions. Among these nine circRNAs, eight were selected to examine their expression response in B. belcheri challenged by pIC in comparison to control using real-time quantitative PCR. The results showed that four circRNAs were induced as part of the antiviral response against pIC, while expression of two circRNAs was decreased, and the expression levels of the remaining two were not significantly altered after pIC challenge. This work is the first to identify circRNAs and reveal their antiviral role in amphioxus. Therefore, it opens a new window to explore the comparative immunology of circRNAs in chordates and the regulatory roles of circRNAs in antiviral immunity in amphioxus.
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Anfioxos/inmunología , Poli I-C/farmacología , ARN/metabolismo , Animales , Expresión Génica , Anfioxos/genética , Anfioxos/metabolismo , MicroARNs/metabolismo , Filogenia , ARN Circular , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ARN/veterinariaRESUMEN
The gills of fish are large mucosal surfaces that are very important portals for pathogen entry. Investigations have shown that microRNAs (miRNAs) are key regulators of immune response to bacterial infections in the gills of fish; however, how miRNA expression changes in response to infection by Gram-positive bacteria remains largely unknown. To further investigate the immunological role of miRNAs in fish gills under pathogen stress induced by Gram-positive bacterial infection, this study investigated Staphylococcus aureus (SA)-induced changes in the miRNAs levels in gills of adult zebrafish (Danio rerio). miRNA microarrays were used to analyze expression profiles of known miRNA in the gills of zebrafish in response to SA infection and compared these to uninfected control fish. A total of 30 differentially expressed miRNAs (DEMs) were identified. Target genes likely regulated by DEMs were predicted, and functional enrichment analyses were performed. The results indicated that DEM targets were primarily involved in innate immune processes, apoptosis, defense responses, and antibacterial responses. Pathways involving bacterial infection, innate immunity, metabolic process, disease, and apoptosis were mediated by DEMs. Furthermore, real-time quantitative PCR experiments for nine key SA-responsive DEMs that regulated the "SA infection" pathway validated the accuracy of microarray results. Dynamic variations in gene expression were surveyed in detail for these key SA-responsive DEMs for PBS control and at 6, 12, 24, and 48â¯h after SA challenge in detail. This study provides novel insight into the mechanisms underlying the miRNA regulation during the SA-induced immune response in zebrafish gills, and provides basic knowledge on the innate immune response against Gram-positive bacterial infection in bony fish.
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Inmunidad Innata/genética , MicroARNs/genética , MicroARNs/inmunología , Pez Cebra/genética , Pez Cebra/inmunología , Animales , Enfermedades de los Peces/inmunología , Branquias/inmunología , Análisis de Secuencia por Matrices de Oligonucleótidos/veterinaria , Infecciones Estafilocócicas/inmunología , Infecciones Estafilocócicas/veterinaria , Staphylococcus aureus/fisiologíaRESUMEN
Bacteriophage endolysins have long been demonstrated to be effective enzybiotics, and have the potential value in the areas of food, agricultural, and industrial science. Traditionally, extraction of recombinant proteins from bacterium E. coli is achieved by chemical, biological or mechanical disruption methods. Here, we present heat treatment, a simple and highly effective method that differs from the conventional ones, for disruption of E. coli cells to extract recombinant TSPphg, an endolysin originated from thermophilic bacteriophage TSP4. In addition, we found that exogenous TSPphg treatment is able to disrupt E. coli cell and release its intracellular proteins, suggesting its great potentiality to be developed as an alternative bacterial cell disruption method. Moreover, the large scale purification of TSPphg by heat treatment can be carried out directly in fermentation broth in situ without complex downstream processing, which may make it a more applicable approach for commercial scale processes. Our findings shed light on recovery of recombinant thermostable proteins and strategy of bacterial cell disruption.
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Bacteriófagos/química , Endopeptidasas/aislamiento & purificación , Proteínas Recombinantes/aislamiento & purificación , Bacteriófagos/genética , Endopeptidasas/química , Endopeptidasas/genética , Escherichia coli/genética , Fermentación , Calor , Proteínas Recombinantes/química , Proteínas Recombinantes/genéticaRESUMEN
Amphioxus, a basal chordate, is widely considered to be an existing proxy of the invertebrate ancestor of vertebrates, and it exhibits susceptibility to various pathogen infections and pathogenic mimic challenges. Here, in order to understand more clearly its antibacterial mechanisms, we analyzed the ribosomal RNA (rRNA)-depleted transcriptome of Chinese amphioxus (Branchiostoma belcheri) infected with Vibrio parahaemolyticus (V. p.) via next-generation deep sequencing technology (RNA-seq). We identified a total of 3214 differentially expressed genes (DEGs) by comparing V. p.-infected and control transcriptome libraries, including 2219 significantly up-regulated and 995 significantly down-regulated DEGs in V. p.-infected amphioxus. The DEGs with the top 10 most dramatic expression fold changes after V. p. infection, as well as 53 immune-related DEGs (IRDs) belonging to four primary categories of innate immunity were analyzed further. Through gene ontology (GO) and pathway enrichment analysis, DEGs were found to be primarily related to immune processes, apoptosis, catabolic and metabolic processes, binding and enzyme activity, while pathways involving bacterial infection, immune signaling, immune response, cancer, and apoptosis were overrepresented. We validated the RNA-seq results by detecting the expression levels of 10 IRDs using qRT-PCR, and we surveyed the dynamic variation in gene expression for these IRDs at 0, 6, 12, 24, and 48â¯h after V. p. TREATMENT: Subsequently, according to the RNA-seq results, the presence of a primitive Toll-like receptor (TLR)-mediated antibacterial immune signaling pathway was predicted in B. belcheri. This study provides valuable information regarding antibacterial immunity for further research into the evolution of immunity in vertebrates and broadens our understanding of the innate immune response against bacterial invasion in amphioxus.
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Inmunidad Innata/genética , Anfioxos/genética , Anfioxos/inmunología , Transcriptoma/inmunología , Vibrio parahaemolyticus/fisiología , Animales , Perfilación de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Interacciones Huésped-Patógeno , Análisis de Secuencia de ARNRESUMEN
Endoscopic endonasal surgery for pituitary adenomas is being performed more frequently worldwide in the recent years. This first bibliometric analysis was conducted aiming to have a microscopic view of research activities about endoscopic endonasal surgery for pituitary adenomas. The original articles about endoscopic endonasal surgery for pituitary adenomas were extracted from the Web of Science (WoS) and analyzed concerning their distributions. We also explored the potential correlations between publications of different countries and their gross domestic product (GDP) via Pearson correlation test. The total number of original articles retrieved from WoS was 307 from 1997 to 2017. The number of original articles published in the last decade has increased by 530.95% compared with that published in the former decade. The United States has published 124 articles (40.391%), followed by Italy with 40 (13.029%) and Japan with 27 articles (8.795%). The journal that published the highest number of original articles was Journal of Neurosurgery with 31 (10.098%), followed by Neurosurgery (nâ=â23, 7.492%), World Neurosurgery (nâ=â23, 7.492%), and Neurosurgical Focus (nâ=â15, 4.886%). There was a strong correlation between publication numbers and GDP of different countries (râ=â0.889, Pâ<â0.001). There is a skyrocket trend of endoscopic endonasal surgery for pituitary adenomas during the last 2 decades, and countries with high GDP tend to make more contributions to this field.
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Endoscopía/estadística & datos numéricos , Procedimientos Neuroquirúrgicos/estadística & datos numéricos , Nariz/cirugía , Neoplasias Hipofisarias/cirugía , Publicaciones/estadística & datos numéricos , Bibliometría , HumanosRESUMEN
Photodetectors with high photoelectronic gain generally require a high negative working voltage and a very low environment temperature. They also exhibit low response speed and narrow linear dynamic range (LDR). Here, an organic photodiode is demonstrated, which shows a large amount of photon to electron multiplication at room temperature with highest external quantum efficiency (EQE) from ultraviolet (UV) to near-infrared region of 5.02 × 103 % (29.55 A W-1 ) under a very low positive voltage of 1.0 V, accompanied with a fast response speed and a high LDR from 10-7 to 101 mW cm-2 . At a relatively high positive bias of 10 V, the EQE is up to 1.59 × 105 % (936.05 A W-1 ). Inversely, no gain is found at negative bias. The gain behavior is exactly similar to a bipolar phototransistor, which is attributed to the photoinduced release of accumulated carriers. The devices at a low voltage exhibit a normalized detectivity (D*) over 1014 Jones by actual measurements, which is about two or three order of magnitudes higher than that of the highest existing photodetectors. These pave a new way for realization of high sensitive detectors with fast response toward the single photon detection.
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Aeromonas hydrophila, an aquatic pathogenic bacterium, has been found to infect many fish species and cause huge aquaculture losses. Antibiotics are the most common drugs used to treat these infections. However, antibiotic abuse can lead to the development of antibiotic resistance. Probiotics have the potential to replace antibiotics for preventing infections. Zebrafish (Danio rerio) is a model organism used to study the innate immune system and host-pathogen interactions. Currently, there is little information on how the fish immune system responds to A. hydrophila and probiotic treatment. To increase the understanding of the molecular mechanisms behind the zebrafish defense against A. hydrophila and provide evidence that antibiotics can be replaced by probiotics, a transcriptome analysis of the zebrafish spleen was conducted 48 hours after infection by A. hydrophila, as well as after treatment using Lactococcus lactis KUST48 4 hours after infection. A total of 36,499 genes were obtained. There were 3,337 genes found to have significant differential expression between treatment and control groups. According to further annotation and enrichment analysis, differentially expressed genes (DEGs) were involved in signal transduction, endocrine system cancer, and the immune system. Insulin resistance disappeared in the zebrafish after treatment. Quantitative real-time PCR was performed to confirm the significant regulation of immune defense DEGs, the results of which were consistent with the RNA-sequencing data. These results could serve as a basis for future studies on the immune response to A. hydrophila and provide suggestions for probiotic alternatives to antibiotics, which will be of great significance to aquaculture and environmental protection.IMPORTANCEIn recent years, the unreasonable use of antibiotics has led to the emergence of drug-resistant pathogenic bacteria, antibiotic residues, cross infection, toxic side effects, and so on, which has caused a serious threat to human food safety and life health. In recent years, many studies have demonstrated the potential of probiotics as a substitute for antibiotics, but there is still a lack of understanding of the molecular mechanisms underlying probiotic therapy. We conduct a research on the impact of Lactococcus lactis KUST48 on the transcription profile of Aeromonas hydrophila-infected zebrafish spleen. Mortality of zebrafish infected with A. hydrophila was significantly reduced after treatment with L. lactis KUST48. Our results can help to strengthen our understanding of the pathogenic mechanisms of zebrafish and provide a valuable reference for the molecular mechanisms of probiotic therapy.
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Enfermedades de los Peces , Infecciones por Bacterias Gramnegativas , Lactococcus lactis , Animales , Humanos , Pez Cebra , Aeromonas hydrophila/genética , Lactococcus lactis/genética , Bazo , Antibacterianos , Infecciones por Bacterias Gramnegativas/veterinaria , Infecciones por Bacterias Gramnegativas/microbiología , Enfermedades de los Peces/microbiologíaRESUMEN
Constructing S-scheme heterojunctions proves proficient in achieving the spatial separation of potent photogenerated charge carriers for their participation in photoreactions. Nonetheless, the restricted contact areas between two phases within S-scheme heterostructures lead to inefficient interfacial charge transport, resulting in low photocatalytic efficiency from a kinetic perspective. Here, In2O3/Nb2O5 S-scheme heterojunctions are fabricated through a straightforward one-step electrospinning technique, enabling intimate contact between the two phases and thereby fostering ultrafast interfacial electron transfer (<10 ps), as analyzed via femtosecond transient absorption spectroscopy. As a result, powerful photo-electrons and holes accumulate in the Nb2O5 conduction band and In2O3 valence band, respectively, exhibiting extended long lifetimes and facilitating their involvement in subsequent photoreactions. Combined with the efficient chemisorption and activation of stable CO2 on the Nb2O5, the resulting In2O3/Nb2O5 hybrid nanofibers demonstrate improved photocatalytic performance for CO2 conversion.
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Two new alkoxy-substituted quinoxaline (Qx)-based copolymers, PBDTQx and PBDTPz, are designed and synthesized. The only difference between these two polymers is that two methyl groups of the Qx are replaced by one additional fused benzene ring. The UV-Vis absorptions, thermal stability, energy levels, field-effect carrier mobility, and photovoltaic characteristics of the two copolymers are systematically evaluated to understand the relationships between the polymer structure at the molecular level and the photovoltaic performances. Photovoltaic cells based on the PBDTPz with a structure of ITO/PEDOT:PSS/Polymer:PC(71) BM/PEO/Ca/Al exhibit a promising efficiency of 4.40%, while that of PBDTQx is relatively much poorer.
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Benceno/química , Polímeros/química , Quinoxalinas/química , Estructura Molecular , Polímeros/síntesis químicaRESUMEN
BACKGROUND: Rectal cancer leads a major disease burden worldwide. Total mesorectal excision (TME) is the standard treatment for locally advanced or node-positive rectal cancer, while attempts to improve the surgery such as laparoscopic and transanal TME are widely used but have their inherent limitations. This bibliometric study analyzed research trends, cooperation, and knowledge dissemination on TME over the past 20 years to inform future directions. METHODS: Relevant literature from 2003 to 2023 was extracted from the Web of Science Core Collection and analyzed with VOSviewer, CiteSpace, and R for publication patterns, countries, institutions, authors, and research hotspots. RESULTS: Five thousand three hundred forty-five related publications were included, with rising annual output and citations. The US and China contributed the most studies, while the Netherlands had greater influence. Leiden University ranked first in publications. The top authors were Heald, Kapiteijn, Sauer, Nagtegaal, and Peeters. Research shifted from cancer-focused to patient-centered care and from radiotherapy/chemotherapy to advanced surgery. Multicenter trials became more common. CONCLUSION: Although the United States and China have the largest number of publications, it should be noted that the influence of these two countries in the field of TME research is not the highest, which does not match the number of publications. In addition, telemedicine, interdisciplinary, medical-industrial integration, etc. may be potential directions for future research in the field of TME.
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Laparoscopía , Neoplasias del Recto , Humanos , Neoplasias del Recto/cirugía , Bibliometría , China , Países BajosRESUMEN
Enrofloxacin (ENFX) has a broad-spectrum antibiotic activity, which is widely used in aquaculture. The effect of different ENFX exposure ways on the gut microbiota of tilapia is unclear. This study was conducted to investigate the effects of ENFX exposure on the gut microbiota of tilapia fish (Oreochromis niloticus). Three methods of ENFX exposure were selected: injection (IEG), oral administration (OEG) and soaking (SEG). After 48 h of exposure period, the intestine of tilapia was collected for high-throughput sequencing. PCoA analysis revealed a distinct clustering of control group, and which was located rather far away from ENFX exposure groups. The dominant phyla in the gut microbiota of tilapia fish were Proteobacteria, Actinobacteriota, Fusobacteria and Firmicutes. Compared to the control group, phylum Fusobacteriota was increased in SEG and IEG while decreased in OEG. ENFX treatment led to a decline in Corynebacterium, Clostridium sensu stricto_3 and Bacillus in treated fish compared with control fish, accompanied by an increase in Akkermansia, Ralstonia and Romboutsia. IEG had the least effect on gut microbiota of tilapia because it retained more microbes among treatment groups. Alpha- diversity decreased the most in SEG, but retained more probiotics such as Cetobacterium and Akkermansia. We assessed the effect of enrofloxacin on tilapia by changes in intestinal flora. The result indicated that either exposure method significantly reduced the diversity of tilapia gut microbiota. It may provide basic data for the scientific use of ENFX in aquaculture.
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Cíclidos , Microbioma Gastrointestinal , Probióticos , Tilapia , Animales , Enrofloxacina/farmacologíaRESUMEN
Antibacterial activity and mechanism of action of bacteriocins against bacteria that cause pork contamination remain unclear. Here, antibacterial activity of bacteriocin LFX01 against two important indicator strains (i.e., Staphylococcus aureus and Escherichia coli) and its mechanism of action were investigated. The results showed antibacterial activity of LFX01 against growth and biofilm formation of S. aureus_26 (strain 2612:1606BL1486) and E. coli_02 (strain CMCC(B)44102). Additionally, the results demonstrated that LFX01 could decrease cell metabolic activity, disrupt cell membrane permeability and integrity, and trigger leakage of intracellular contents (e.g., K+, ATP, and lactic dehydrogenase). Furthermore, gel retardation showed that LFX01 could bind to the genomic DNA of indicator strains, disrupting DNA structure. These results uncovered mechanism of action of LFX01 against indicator strains from physiological and phenotypic levels. When applied to the surface of fresh pork models, the antibacterial activity of LFX01 against indicator strains was further confirmed. These findings suggested that LFX01 could be a potential pork preservative for controlling foodborne pathogens.
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Bacteriocinas , Carne de Cerdo , Carne Roja , Porcinos , Animales , Staphylococcus aureus , Escherichia coli , Bacteriocinas/farmacología , Antibacterianos/farmacologíaRESUMEN
n-Doped small molecular organic thermoelectric materials (OTMs) hold advantages of high Seebeck coefficient and better performance reproducibility over their polymeric analogues; however, high-performance n-type small molecular OTMs are severely lacking. We report here a class of small molecular OTMs based on terminal cyanation of a bithiophene imide-based ladder-type heteroarene BTI2. It was found that the cyanation could effectively lower the lowest unoccupied molecular orbital (LUMO) level from -2.90 eV (BTI2) to -4.14 eV (BTI2-4CN) and thus lead to significantly improved n-doping efficiency. Additionally, terminal cyano-functionalization can maintain the close packing and efficient intermolecular charge transfer between these cyanated molecules, thus yielding high electron mobilities of up to 0.40 cm2 V-1 s-1. Benefiting from its low LUMO-enabled efficient n-doping and high electron mobility, an encouraging n-type electrical conductivity of 0.43 S cm-1 and power factor (PF) of 6.34 µW m-1 K-2 were achieved for tetracyanated BTI2-4CN, significantly outperforming those of its noncynated BTI2 (<10-7 S cm-1, PF undetectable) and dicyanated BTI2-2CN (0.24 S cm-1, 1.78 µW m-1 K-2). These results suggest the great potential of the terminal cyanation strategy of ladder-type heteroarenes for developing high-performance small molecular OTMs.
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OBJECTIVE: This study aimed to explore the correlation between T1 and T2 relaxation times of synthetic MRI (SyMRI) and gestational age (GA) in each hemisphere of preterm and term newborns at the initial 28 days of birth. METHODS: Seventy preterm and full-term infants were prospectively included in this study. All subjects completed 3.0 T routine MRI and SyMRI (MAGiC) one-stop scanning within 28 days of birth (aged 34-42 W at examination). The SyMRI postprocessing software (v8.0.4) was used to measure the T1 and T2 relaxation values of each brain region. The linear regression equations of quantitative relaxation values with GA were established to compare the variation speed in each brain region. RESULTS: A significant linear and negative correlation was found between relaxation times and GA in the neonate cerebral cortex and subcortical gray and white matter regions (All p<.05). The relaxation time of the left centrum semiovale decreased with maximum variance with increasing GA among all white matter regions (T1: b = -51.45, ß = -0.65, p < .0001; T2: b = -8.77, ß = -0.71, p < .0001), whereas the right posterior limb of internal capsule showed minimal variance (T1: b = -27.94, ß = -0.60, p < .0001; T2: b = -3.25, ß = -0.68, p < .0001). Among all gray matter regions, the right globus pallidus and thalamus indicated the most significant decreasing degree of T1 and T2 relaxation values with GA (right globus pallidus T1: b = -33.14, ß = -0.64, p < .0001; right thalamus T2: b = -3.94, ß = -0.81, p < .0001), and the right and left occipital lobes indicated the least significant decreasing degree of T1 and T2 relaxation values with GA, respectively (right occipital lobes T1: b = -11.18, ß = -0.26, p = .028; left occipital lobes T2: b = -1.22, ß = -0.27, p = .024). CONCLUSIONS: SyMRI could quantitatively evaluate the linear changes of T1 and T2 relaxation values with GA in brain gray and white matter of preterm and term neonates.