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Complex concentrated solutions of multiple principal elements are being widely investigated as high- or medium-entropy alloys (HEAs or MEAs)1-11, often assuming that these materials have the high configurational entropy of an ideal solution. However, enthalpic interactions among constituent elements are also expected at normal temperatures, resulting in various degrees of local chemical order12-22. Of the local chemical orders that can develop, chemical short-range order (CSRO) is arguably the most difficult to decipher and firm evidence of CSRO in these materials has been missing thus far16,22. Here we discover that, using an appropriate zone axis, micro/nanobeam diffraction, together with atomic-resolution imaging and chemical mapping via transmission electron microscopy, can explicitly reveal CSRO in a face-centred-cubic VCoNi concentrated solution. Our complementary suite of tools provides concrete information about the degree/extent of CSRO, atomic packing configuration and preferential occupancy of neighbouring lattice planes/sites by chemical species. Modelling of the CSRO order parameters and pair correlations over the nearest atomic shells indicates that the CSRO originates from the nearest-neighbour preference towards unlike (V-Co and V-Ni) pairs and avoidance of V-V pairs. Our findings offer a way of identifying CSRO in concentrated solution alloys. We also use atomic strain mapping to demonstrate the dislocation interactions enhanced by the CSROs, clarifying the effects of these CSROs on plasticity mechanisms and mechanical properties upon deformation.
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The strength-ductility trade-off has long been a Gordian knot in conventional metallic structural materials and it is no exception in multi-principal element alloys. In particular, at ultrahigh yield strengths, plastic instability, that is, necking, happens prematurely, because of which ductility almost entirely disappears. This is due to the growing difficulty in the production and accumulation of dislocations from the very beginning of tensile deformation that renders the conventional dislocation hardening insufficient. Here we propose that premature necking can be harnessed for work hardening in a VCoNi multi-principal element alloy. Lüders banding as an initial tensile response induces the ongoing localized necking at the band front to produce both triaxial stress and strain gradient, which enables the rapid multiplication of dislocations. This leads to forest dislocation hardening, plus extra work hardening due to the interaction of dislocations with the local-chemical-order regions. The dual work hardening combines to restrain and stabilize the premature necking in reverse as well as to facilitate uniform deformation. Consequently, a superior strength-and-ductility synergy is achieved with a ductility of ~20% and yield strength of 2 GPa during room-temperature and cryogenic deformation. These findings offer an instability-control paradigm for synergistic work hardening to conquer the strength-ductility paradox at ultrahigh yield strengths.
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Recent characterization of the obligate episymbiont Saccharibacteria (TM7) belonging to the candidate phyla radiation (CPR) has expanded the extent of microbial diversity. However, the episymbiotic lifestyle of TM7 is still underexploited due to the deficiency of cultivated representatives. Here, we describe gene-targeted TM7 cultivation guided by repurposing epicPCR (emulsion, paired isolation, and concatenation PCR) to capture in situ TM7âhost associations. Using this method, we obtained a novel Saccharibacteria isolate TM7i and its host Leucobacter aridicollis J1 from Cicadae Periostracum, the castoff shell of cicada. Genomic analyses and microscopic characterizations revealed that TM7i could bind to J1 through twitching-like motility mediated by type IV pili (T4P). We further showed that the inhibition of T4P extrusion suppressed the motility and host adherence of TM7i, resulting in its reduced growth. However, the inactivation of T4P had little effect on the growth of TM7i that had already adhered to J1, suggesting the essential role of T4P in host recognition by TM7i. By capturing CPRâhost association and elaborating the T4P-dependent episymbiotic association mechanism, our studies shed light on the distinct yet widespread lifestyle of CPR bacteria.
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Actinomycetales , Fimbrias Bacterianas , Fimbrias Bacterianas/genética , Bacterias , Reacción en Cadena de la Polimerasa , GenómicaRESUMEN
Haloarchaea with the capacity to degrade alkanes is promising to deal with petroleum pollution in hypersaline environments. However, only a limited number of haloarchaeal species are investigated, and their pathway and mechanism for alkane degradation remain unclear. In this study, Halogranum rubrum RO2-11, a haloarchaeal strain, verified the ability to degrade kerosene and hexadecane in 184 g/L NaCl, with 53% and 52% degradation rates after 9 and 4 days, respectively. Genome sequencing and gene annotation indicated that strain RO2-11 possesses a complete potential alkane-degrading pathway, of which alkane hydroxylases may include CYP450, AlmA, and LadA. Transcriptome and metabolome analyses revealed that the upregulation of related genes in TCA cycle, lysine biosynthesis, and acetylation may help improve hexadecane degradation. Additionally, an alternative degrading pathway of hexadecane based on dual-terminal ß-oxidation may occur in strain RO2-11. It is likely to be the first report of alkane degradation by the genus Halogranum, which may be helpful for applications of oil-pollution bioremediation under high-salt conditions.
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Alcanos , Biodegradación Ambiental , Alcanos/metabolismo , Halobacteriaceae/genética , Halobacteriaceae/metabolismo , MultiómicaRESUMEN
Iridium(III) complexes are emerging as a promising tool in the area of detection and therapy due to their prominent photophysical properties, including higher photostability, tunable phosphorescence emission, long-lasting phosphorescence, and high quantum yields. In recent years, much effort has been devoted to develop novel near-infrared (NIR) iridium(III) complexes to improve signal-to-noise ratio and enhance tissue penetration. In this review, we summarize different classes of organometallic NIR iridium(III) complexes for detection and therapy, including cyclometalated ligand-enabled NIR iridium(III) complexes and NIR-dye-conjugated iridium(III) complexes. Moreover, the prospects and challenges for organometallic NIR iridium(III) complexes for targeted detection and therapy are discussed.
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Iridio , Relación Señal-RuidoRESUMEN
This study aims to construct the element relationship and extension path of clinical evidence knowledge map with Chinese patent medicine, providing basic technical support for the formation and transformation of the evidence chain of Chinese patent medicine and providing collection, induction, and summary schemes for massive and disorganized clinical data. Based on the elements of evidence-based PICOS, the conventional construction methods of knowledge graph were collected and summarized. Firstly, the data entities related to Chinese patent medicine were classified, and entity linking was performed(disambiguation). Secondly, the study associated and classified the attribute information of the data entity. Finally, the logical relationship between entities was constructed, and then the element relationship and extension path of the knowledge map conforming to the characteristics of clinical evidence of Chinese patent medicine were summarized. The construction of the clinical evidence knowledge map of Chinese patent medicine was mainly based on process design and logical structure, and the element relationship of the knowledge map was expressed according to the PICOS principle and evidence level. The extension path crossed three levels(model layer, data layer application, and new evidence application), and the study gradually explored the path from disease, core evaluation indicators, Chinese patent medicine, core prescriptions, syndrome and treatment rules, and medical case comparison(evolution law) to new drug research and development. In this study, the top-level design of the construction of the clinical evidence knowledge map of Chinese patent medicine has been clarified, but it still needs the joint efforts of interdisciplinary disciplines. With the continuous improvement of the map construction technology in line with the characteristics of TCM, the study can provide necessary basic technical support and reference for the development of the TCM discipline.
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Medicamentos Herbarios Chinos , Medicamentos Herbarios Chinos/uso terapéutico , Medicina Tradicional China , Medicamentos sin Prescripción/uso terapéutico , Tecnología , Minería de Datos/métodosRESUMEN
BACKGROUND: So far, rare cases of B cell lymphoproliferative diseases with rod crystals inclusions had been reported. METHODS: Wright's stain and MPO stain are used for cell and rod crystal staining while the immunophenotype examination, fluorescence in situ hybridization probes, routine G-band cytogenetic analysis and molecular biological tests are used to diagnose the disease which is chronic lymphocytic leukemia. RESULTS: One to six colorless rod-like crystals can be seen in some mature lymphocytes of the peripheral blood smear and also colorless by MPO staining. The immunophenotype examination with flow cytometry shows it is consistent with chronic lymphocytic leuke mia/B small lymphocytic lymphoma. CONCLUSIONS: The discovery of this rare phenomenon of rod-shaped crystallization in the peripheral blood may contribute to the diagnosis of lymphoproliferative diseases in B cells.
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Leucemia Linfocítica Crónica de Células B , Trastornos Linfoproliferativos , Humanos , Leucemia Linfocítica Crónica de Células B/diagnóstico , Hibridación Fluorescente in Situ , Linfocitos B , Trastornos Linfoproliferativos/diagnóstico , Citometría de Flujo , InmunofenotipificaciónRESUMEN
OBJECTIVES: This study aimed to investigate the relationship between microbial communities and the severity of peri-implant mucosal bleeding in peri-implant mucositis. MATERIALS AND METHODS: Submucosal plaque samples were collected from 54 implants divided into the healthy implant (HI) group, peri-implant mucositis (PM) group, and peri-implantitis (PI) group. Sequencing of 16S rRNA was performed using the Illumina MiSeq platform. Alpha diversity (i.e., Shannon and Chao index) and beta diversity were used to measure microbial diversity within and between microbial communities, respectively. Differences in microbial taxa between groups were assessed via linear discriminate analysis effect size. Correlation between the modified sulcus bleeding index (mSBI) and microbial dysbiosis index (MDI) was examined using Spearman correlation analysis and linear models. RESULTS: The submucosal bacterial richness (Chao index) was positively correlated with the mean mSBI in the PM group. As the mean mSBI increased in the PM group, the beta diversity became closer to that of the PI group. In the PM group, the abundances of 47 genera were significantly correlated with the mean mSBI, and the MDI was positively associated with the mean mSBI. Fourteen of the forty-seven genera were discriminative taxa between the HI and PI groups, and the abundances of these biomarkers became closer to those in the PI group in the progression of peri-implant disease. CONCLUSIONS: A higher mSBI value corresponded to a higher risk of microbial dysbiosis in peri-implant mucositis. The biomarkers identified may be useful for monitoring the progression of peri-implant disease.
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Implantes Dentales , Mucositis , Periimplantitis , Periodontitis , Humanos , Periimplantitis/microbiología , Implantes Dentales/efectos adversos , Implantes Dentales/microbiología , Mucositis/microbiología , Disbiosis , ARN Ribosómico 16S/genética , BiomarcadoresRESUMEN
Microbes use both organic and inorganic compounds as electron donors, with different electronic potentials, to produce energy required for growth in environments. Conventional studies on the effects of different electron donors on microbial community has been extensively studied with a set cathode potential. However, it remains under-researched how a microbial community response to the different redox potentials in different environments. Here, we incubated a lake sediment in a single-chamber reactor equipped with three working electrodes, i.e., with potentials of - 0.29 V, - 0.05 V versus standard hydrogen electrode and open-circuit, respectively. Results reveal that the structure of bacterial communities was highly similar for all closed-circuit electrodes (- 0.29 V, - 0.05 V), while differing significantly from those on open-circuit electrodes. We also show that specific bacteria were preferentially enriched by different electrode potentials, i.e., Pseudomonas and Rhodobacter preferentially grew on - 0.05 V and - 0.29 V cathode potentials, Azospirillum and Bosea preferentially grew on - 0.05 V; while Ferrovibrio, Hydrogenophaga, Delftia, and Sphingobium preferentially grew on - 0.29 V. In addition, microorganisms selectively enriched on open-circuit electrodes possess higher connectivity and closer relationship than microorganisms selectively enriched on closed-circuit electrode.
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Fuentes de Energía Bioeléctrica , Microbiota , Fuentes de Energía Bioeléctrica/microbiología , Bacterias/genética , ElectrodosRESUMEN
BACKGROUND: Both Kinesio Tape (KT) and Compression Sleeves (CS) can relieve Delayed Onset Muscle Soreness (DOMS) to a certain extent, but there is no study report on the difference in the effectiveness of the KT and CS whether the effect is better when used at the same time. The purpose of this study was to compare the effects of KT and CS on the recovery of muscle soreness, isokinetic strength, and body fatigue after DOMS. METHODS: In this single-blinded randomized controlled trial, 32 participants aged 18 to 24 years were randomly divided into Control group (CG), Compression Sleeves group (CSG), Kinesio Tape group (KTG), Compression Sleeves and Kinesio Tape group (CSKTG), between October 2021 and January 2022. KTG uses Kinesio Tape, CSG wears Compression Sleeves, and CSKTG uses both Compression Sleeves and Kinesio Tape. Outcomes were performed at five-time points (baseline, 0 h, 24 h, 48 h, 72 h), Primary outcome was pain level Visual Analogue Scale (VAS), and Secondary outcomes were Interleukin 6, Peak Torque/Body Weight, Work Fatigue. Statistical analyses were performed using the repeated measures analysis of variance method. SETTING: Laboratory. RESULTS: After the intervention, VAS reached the highest at 24 h after exercise-induced muscle soreness, while the KTG and CSG at each time point were less than CG, and the scores of CSKTG at 24 h and 48 h were less than those of KTG and CSG in the same period (P < 0.05). Interleukin 6, at 24 h, CSKTG is lower than KTG 0.71(95%CI: 0.43 to 1.86) and CG 1.68(95%CI: 0.06 to 3.29). Peak Torque/Body Weight, at 24 h, CG was lower than CSKTG 0.99(95%CI: 0.42 to 1.56), KTG 0.94(95%CI: 0.37 to 1.52), and CSG 0.72(95%CI: 0.14 to 1.29); at 72 h, CG was lower than CSKTG 0.65(95%CI: 0.13 to 1.17) and KTG 0.58(95%CI: 0.06 to 1.10). Work Fatigue, at 24 h, CG was lower than KTG 0.10(95%CI: 0.02 to 1.78) and CSKTG 0.01(95%CI: -0.07 to 0.09). At 48 h, CG was lower than KTG 0.10(95%CI: 0.13 to 1.17) and CSKTG 0.11(95%CI: 0.03 to 0.18). CONCLUSIONS: Kinesio Tape can significantly reduce DOMS pain, and Kinesio Tape has a better recovery effect on Delayed Onset Muscle Soreness than Compression Sleeves. Kinesio Tape combined with Compression Sleeves is helpful to alleviate the Delayed Onset Muscle Soreness pain, speeding up the recovery of muscle strength, and shortening the recovery time after Delayed Onset Muscle Soreness. TRIAL REGISTRATION: Registration number: This study was also registered on 11/10/2021, at the Chinese Clinical Trial Registry (ChiCTR2100051973).
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Cinta Atlética , Mialgia , Humanos , Mialgia/etiología , Mialgia/terapia , Interleucina-6 , Terapia por Ejercicio , FatigaRESUMEN
Multiple resistance and pH adaptation (Mrp) complexes are sophisticated cation/proton exchangers found in a vast variety of alkaliphilic and/or halophilic microorganisms, and are critical for their survival in highly challenging environments. This family of antiporters is likely to represent the ancestor of cation pumps found in many redox-driven transporter complexes, including the complex I of the respiratory chain. Here, we present the three-dimensional structure of the Mrp complex from a Dietzia sp. strain solved at 3.0-Å resolution using the single-particle cryoelectron microscopy method. Our structure-based mutagenesis and functional analyses suggest that the substrate translocation pathways for the driving substance protons and the substrate sodium ions are separated in two modules and that symmetry-restrained conformational change underlies the functional cycle of the transporter. Our findings shed light on mechanisms of redox-driven primary active transporters, and explain how driving substances of different electric charges may drive similar transport processes.
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Actinobacteria/ultraestructura , Complejos Multiproteicos/ultraestructura , Conformación Proteica , Intercambiadores de Sodio-Hidrógeno/ultraestructura , Actinobacteria/química , Transporte Biológico , Microscopía por Crioelectrón , Cristalografía por Rayos X , Complejo I de Transporte de Electrón/ultraestructura , Escherichia coli/genética , Concentración de Iones de Hidrógeno , Complejos Multiproteicos/química , Oxidación-Reducción , Bombas de Protones/química , Bombas de Protones/genética , Bombas de Protones/ultraestructura , Intercambiadores de Sodio-Hidrógeno/química , Intercambiadores de Sodio-Hidrógeno/genéticaRESUMEN
BACKGROUND: Recent studies have shown that the up-regulation of microRNA miR-328-3p expression increases seasonal allergy and asthma symptoms in children, but the specific mechanism remains unclear. Therefore, the aim of this study was to explore the role and mechanism of -miR-328-3p in transforming growth factor (TGF)-ß1-induced airway smooth muscle cells (ASMCs). METHODS: The effect of TGF-ß1 on the expression of miR-328-3p in ASMCs was examined by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). Cells proliferation, migration, and inflammatory factors in TGF-ß1-induced ASMCs were measured by cell counting kit-8 (CCK-8), transwell, and enzyme-linked immunosorbent assay (ELISA), respectively. Besides, TargetScan was used to predict phosphatase and tensin homolog (PTEN), the downstream target of miR-328-3p; double-luciferase reporter assay, western blot, and qRT-PCR were used to verify the targeting relationship between miR-328-3p and PTEN; western blot was also used to examine the effects of PTEN and miR-328-3p knockdown on the expression levels of PTEN, Akt, and p-Akt proteins. RESULTS: The expression of miR-328-3p was up-regulated in TGF-ß1-induced ASMCs. Knockdown of miR-328-3p significantly inhibited proliferation, migration, and inflammation of ASMCs induced by TGF-ß1 and decreased levels of tumor necrosis factor (TNF)-α and interleukin (IL)-1ß. The dual--luciferase reporter assay results confirmed that PTEN was a target gene of miR-328-3p. Moreover, inhibition of PTEN expression reversed the inhibitory effect of low miR-328-3p expression on -TGF-ß1-induced ASMC's proliferation, migration, and inflammation. In comparison to the knockdown of miR-328-3p alone, the simultaneous knockdown of miR-328-3p with PTEN decreased PTEN protein expression levels and increased p-Akt/Akt ratio in TGF-ß1-induced ASMCs. CONCLUSION: Through regulating the expression of PTEN and the activity of Akt signaling pathway, miR-328-3p promotes TGF-ß1-induced proliferation, migration, and inflammation of ASMCs.
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MicroARNs , Proteínas Proto-Oncogénicas c-akt , Niño , Humanos , Movimiento Celular , Proliferación Celular/genética , Inflamación/patología , MicroARNs/genética , MicroARNs/metabolismo , Miocitos del Músculo Liso , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo , Fosfohidrolasa PTEN/farmacología , Factor de Crecimiento Transformador beta1/genéticaRESUMEN
Non-coding RNAs have been excavated as important cardiac function modulators and linked to heart diseases. Significant advances have been obtained in illuminating the effects of microRNAs and long non-coding RNAs. Nevertheless, the characteristics of circular RNAs are rarely mined. Circular RNAs (circRNAs) are widely believed to participate in cardiac pathologic processes, especially in myocardial infarction. In this review, we round up the biogenesis of circRNAs, briefly describe their biological functions, and summarize the latest literature on multifarious circRNAs related to new therapies and biomarkers for myocardial infarction.
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MicroARNs , Infarto del Miocardio , ARN Largo no Codificante , Humanos , ARN Circular , BiomarcadoresRESUMEN
The deleterious effects of drought stress have led to a significant decline in vegetable production, ultimately affecting food security. After sensing drought stress signals, vegetables prompt multifaceted response measures, eventually leading to changes in internal cell structure and external morphology. Among them, it is important to highlight that the changes, including changes in physiological metabolism, signal transduction, key genes, and hormone regulation, significantly influence drought stress tolerance in vegetables. This article elaborates on vegetable stress tolerance, focusing on structural adaptations, key genes, drought stress signaling transduction pathways, osmotic adjustments, and antioxidants. At the same time, the mechanisms of exogenous hormones such as abscisic acid (ABA), jasmonic acid (JA), salicylic acid (SA), and ethylene (ET) toward improving the adaptive drought tolerance of vegetables were also reviewed. These insights can enhance the understanding of vegetable drought tolerance, supporting vegetable tolerance enhancement by cultivation technology improvements under changing climatic conditions, which provides theoretical support and technical reference for innovative vegetable stress tolerance breeding and food security.
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Sequías , Verduras , Fitomejoramiento , Resistencia a la Sequía , HormonasRESUMEN
Hydrocarbon-degrading bacteria typically metabolize a broad range of alkane substrates, but global metabolic characteristics of strains growing on alkane substrates in different chain lengths remain unclear. In this study, we analysed the transcriptional profiles of a hydrocarbon degrading bacterium, Dietzia sp. DQ12-45-1b, during growth on octacosane (C28), hexadecane (C16) and glucose as the sole carbon sources. Our results highlight that C16 and C28 induced common genes of core alkane degradation pathways in DQ12-45-1b, whereas transcriptional patterns of genes related to lipid metabolism, energy metabolism, biomass synthesis, and metal ion transportation were distinct. In addition, the transcriptional differences of genes related to glyoxylate shunt (GS) as well as growth phenotypes of mutant strain with defects in GS demonstrated that GS is essential for C16 degradation, though it is dispensable for C28 degradation in DQ12-45-1b. These results demonstrate that DQ12-45-1b cells exhibited considerable metabolic flexibility by using various mechanisms during growth on alkane substrates in different chain lengths. This study advances our knowledge of microbial hydrocarbon degradation and provides valuable information for the application of alkane-degrading bacteria in bioremediation and microbial enhanced oil recovery.
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Actinomycetales , Actinomycetales/genética , Alcanos/metabolismo , Biodegradación Ambiental , Perfilación de la Expresión Génica , Hidrocarburos/metabolismoRESUMEN
BACKGROUND: The immune system has been implicated in synaptic plasticity, inflammation, and the progression of Alzheimer's disease (AD). However, there were few studies on improving the niche microenvironment of neural stem cells (NSCs) in the brain of AD to promote adult hippocampal neurogenesis (AHN) by regulating the function of non-parenchymal immune cells. METHODS: The lymph nodes of amyloid precursor protein/presenilin 1 (APP/PS1) and 3xTg (APP/PS1/tau) mouse models of AD were treated with photobiomodulation therapy (PBMT) for 10 J/cm2 per day for 1 month (10 min for each day), T lymphocytes isolated from these two AD models were treated with PBMT for 2 J/cm2 (5 min for each time). The NSCs isolated from hippocampus of these two AD models at E14, and the cells were co-cultivated with PBMT-treated T lymphocyte conditioned medium for NSCs differentiation. RESULTS: Our results showed that PBMT treatment could promote AHN and reverse cognitive deficits in AD mouse model. The expression of interferon-γ (IFN-γ) and interleukin-10 (IL-10) was upregulated in the brain of these two AD models after PBMT treated, which was induced by the activation of Janus kinase 2 (JAK2)-mediated signal transducer and activator of transcription 4 (STAT4)/STAT5 signaling pathway in CD4+ T cells. In addition, elevated CD4+ T cell levels and upregulated transforming growth factor-ß1 (TGFß1)/insulin-like growth factors-1 (IGF-1)/brain-derived neurotrophic factor (BDNF) protein expression levels were also detected in the brain. More importantly, co-cultivated the PBMT-treated T lymphocyte conditioned medium with NSCs derived from these two AD models was shown to promote NSCs differentiation, which was reflected in the upregulation of both neuronal class-III ß-tubulin (Tuj1) and postsynaptic density protein 95 (PSD95), but the effects of PBMT was blocked by reactive oxygen species (ROS) scavenger or JAK2 inhibitor. CONCLUSION: Our research suggests that PBMT exerts a beneficial neurogenesis modulatory effect through activating the JAK2/STAT4/STAT5 signaling pathway to promote the expression of IFN-γ/IL-10 in non-parenchymal CD4+ T cells, induction of improvement of brain microenvironmental conditions and alleviation of cognitive deficits in APP/PS1 and 3xTg-AD mouse models.
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Enfermedad de Alzheimer , Terapia por Luz de Baja Intensidad , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/terapia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Linfocitos T CD4-Positivos/metabolismo , Cognición , Medios de Cultivo Condicionados/farmacología , Modelos Animales de Enfermedad , Homólogo 4 de la Proteína Discs Large/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Janus Quinasa 2/metabolismo , Ratones , Ratones Transgénicos , Neurogénesis/fisiología , Presenilina-1/genética , Presenilina-1/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factor de Transcripción STAT4/metabolismo , Factor de Transcripción STAT5/metabolismo , Factor de Transcripción STAT5/farmacología , Linfocitos T/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Tubulina (Proteína)/metabolismoRESUMEN
Two-component systems (TCSs) act as common regulatory systems allowing bacteria to detect and respond to multiple environmental stimuli, including cell envelope stress. The MtrAB TCS of Actinobacteria is critical for cell wall homeostasis, cell proliferation, osmoprotection, and antibiotic resistance, and thus is found to be highly conserved across this phylum. However, how precisely the MtrAB TCS regulates cellular homeostasis in response to environmental stress remains unclear. Here, we show that the MtrAB TCS plays an important role in the tolerance to different types of cell envelope stresses, including environmental stresses (i.e., oxidative stress, lysozyme, SDS, osmotic pressure, and alkaline pH stresses) and envelope-targeting antibiotics (i.e., isoniazid, ethambutol, glycopeptide, and ß-lactam antibiotics) in Dietzia sp. DQ12-45-1b. An mtrAB mutant strain exhibited slower growth compared to the wild-type strain and was characterized by abnormal cell shapes when exposed to various environmental stresses. Moreover, deletion of mtrAB resulted in decreased resistance to isoniazid, ethambutol, and ß-lactam antibiotics. Further, Cleavage under targets and tagmentation sequencing (CUT&Tag-seq) and electrophoretic mobility shift assays (EMSAs) revealed that MtrA binds the promoters of genes involved in peptidoglycan biosynthesis (ldtB, ldtA, murJ), hydrolysis (GJR88_03483, GJR88_4713), and cell division (ftsE). Together, our findings demonstrated that the MtrAB TCS is essential for the survival of Dietzia sp. DQ12-45-1b under various cell envelope stresses, primarily by controlling multiple downstream cellular pathways. Our work suggests that TCSs act as global sensors and regulators in maintaining cellular homeostasis, such as during episodes of various environmental stresses. The present study should shed light on the understanding of mechanisms for bacterial adaptivity to extreme environments. IMPORTANCE The multilayered cell envelope is the first line of bacterial defense against various extreme environments. Bacteria utilize a large number of sensing and regulatory systems to maintain cell envelope homeostasis under multiple stress conditions. The two-component system (TCS) is the main sensing and responding apparatus for environmental adaptation. The MtrAB TCS highly conserved in Actinobacteria is critical for cell wall homeostasis, cell proliferation, osmoprotection, and antibiotic resistance. However, how MtrAB works with regard to signals impacting changes to the cell envelope is not fully understood. Here, we found that in the Actinobacterium Dietzia sp. DQ12-45-1b, a TCS named MtrAB is pivotal for ensuring normal cell growth as well as maintaining proper cell morphology in response to various cell envelope stresses, namely, by regulating the expression of cell envelope-related genes. Our findings should greatly advance our understanding of the adaptive mechanisms responsible for maintaining cell integrity in times of sustained environmental shocks.
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Actinobacteria , Actinomycetales , Muramidasa/metabolismo , Peptidoglicano/metabolismo , Etambutol/metabolismo , Isoniazida/metabolismo , Actinomycetales/genética , Pared Celular/metabolismo , Actinobacteria/genética , Actinobacteria/metabolismo , Antibacterianos/farmacología , Antibacterianos/metabolismo , beta-Lactamas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión GénicaRESUMEN
The present study collected, collated, analyzed, and evaluated randomized controlled trial(RCT) of Chinese patent medicine published in Chinese and English journals in 2020, and summarized clinical evidence of Chinese patent medicine in stages, providing references for follow-up clinical research and evidence transformation and application. On the basis of the collection in the Traditional Chinese Medicine(TCM) Clinical Evidence Database System(EVDS), CNKI, Wanfang, SinoMed, Cochrane Library, PubMed, and EMbase were searched for RCTs of Chinese patent medicine published in 2020, and their research characteristics and methodological quality were analyzed and evaluated. A total of 1 285 research papers on Chinese patent medicine(1 257 in Chinese/28 in English) were included, involving 146 054 patients and 639 Chinese patent medicines, including 526 oral drugs, 68 injections, and 45 external drugs. A total of 412 diseases in 23 types were involved, which were dominated by circulatory system diseases and respiratory system diseases, specifically, cerebral infarction and angina pectoris. The sample size ranged from 20 cases to 2 673 cases, and 57.67% of RCTs had samples sizes less than 100. Single-center trials were the main ones, and multi-center trials only accounted for 4.75%(n=61). In terms of methodological quality, 52.91% of the RCTs had unclear descriptions or incorrect application of randomization methods, and the implementation of allocation concealment and blinding methods has not been paid much attention. In conclusion, compared with the conditions in 2019, the number of RCTs published in 2020 has decreased, and the research interest in respiratory diseases has increased, while the quality control in the process of research design and implementation has not been improved. Therefore, it is necessary to strengthen the methodological training of researchers and promote the output of high-quality research evidence.
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Medicamentos Herbarios Chinos , Medicamentos sin Prescripción , China , Medicamentos Herbarios Chinos/uso terapéutico , Humanos , Medicina Tradicional China , Control de CalidadRESUMEN
The present study systematically collected, analyzed, and evaluated randomized controlled trial(RCT) of Chinese patent medicine in the treatment of heart failure to provide references for follow-up clinical research design, guideline update, and policy formulation, and promote the improvement of clinical evidence quality. On the basis of the collection in the Traditional Chinese Medicine(TCM) Clinical Evidence Database System(EVDS), CNKI, VIP, Wanfang, SinoMed, PubMed, and Web of Science were searched for RCTs of Chinese patent medicine in the treatment of heart failure from database inception to December 31, 2020. The di-sease type, publication time, sample size, intervention/control setting, course of treatment, evaluation indexes, and methodological quality were analyzed and evaluated. A total of 1 631 RCTs were included, including 1 622 in Chinese and 9 in English. It was first published in 1995, with the largest number of publications in 2016. There were only 56 RCTs(3.43%) with a sample size≥200. Seventy-eight types of Chinese patent medicines were involved, including 49 types of oral drugs and 29 types of injections. There were 34 intervention/control protocols, which were dominated by Chinese patent medicine+conventional treatment vs conventional treatment, accounting for 28.51%(n=465). About 94.0% of RCTs reported the course of treatment, mainly 14-56 days. The evaluation indexes were mainly physical and chemical tests and symptoms/signs, and left ventricular ejection fraction(LVEF) was the most frequently used measurement index. In enumeration indexes, clinical efficacy(response rate) was used the most frequently. Methodologically, 92.0% of the research subjects were rated as high risk of blindness. There were only 13 RCTs(0.80%) reporting registered information. It is necessary to further standardize the design, implementation, and quality control of clinical studies in order to improve the quality of evidence and avoid research waste.
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Medicamentos Herbarios Chinos , Insuficiencia Cardíaca , China , Medicamentos Herbarios Chinos/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Medicina Tradicional China , Medicamentos sin Prescripción/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Volumen Sistólico , Función Ventricular IzquierdaRESUMEN
Membrane vesicles (MVs) released from bacteria act as extracellular vehicles carrying various functional cargoes between cells. MVs with different cargoes play multiple roles in stress adaptation, nutrient acquisition and microbial interactions. However, previous studies have primarily focused on MVs from Gram-negative bacteria, while the characteristics of cargoes in MVs from Gram-positive bacteria and their involvement in microbial interactions remain to be elucidated. Here, we used a Gram-positive strain, Dietzia sp. DQ12-45-1b from Corynebacteriales, to analyse the characteristics and functions of MVs. We identified the 'antioxidant' canthaxanthin is stored within MVs by LC-MS/MS. In addition, nearly the entire genomic content of strain DQ12-45-1b are evenly distributed in MVs, suggesting that MVs from DQ12-45-1b might involve in horizontal gene transfer. Finally, the mycobactin-type siderophores were detected in MVs. The iron-loaded MVs effectively mediate iron binding and delivery to homologous bacteria from the order Corynebacteriales, but not to more distantly related species from the orders Pseudomonadales, Bacillales and Enterobacterales. These results revealed that the iron-loaded MVs are shared between homologous species. Together, we report the Gram-positive bacterium Dietzia sp. DQ12-45-1b released MVs that contain canthaxanthin, DNA and siderophores and prove that MVs act as public goods between closely related species.