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Purely quantum electron systems exhibit intriguing correlated electronic phases by virtue of quantum fluctuations in addition to electron-electron interactions. To realize such quantum electron systems, a key ingredient is dense electrons decoupled from other degrees of freedom. Here, we report the discovery of a pure quantum electron liquid that spreads up to ~3 Å in a vacuum on the surface of an electride crystal. Its extremely high electron density and weak hybridization with buried atomic orbitals show the quantum and pure nature of the electrons, which exhibit a polarized liquid phase, as demonstrated by our spin-dependent measurement. Furthermore, upon enhancing the electron correlation strength, the dynamics of the quantum electrons change to that of a non-Fermi liquid along with an anomalous band deformation, suggestive of a transition to a hexatic liquid crystal phase. Our findings develop the frontier of quantum electron systems and serve as a platform for exploring correlated electronic phases in a pure fashion.
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Uniform-size, non-native oxide-passivated metallic aluminum nanoparticles (Al NPs) have desirable properties for fuel applications, battery components, plasmonics, and hydrogen catalysis. Nonthermal plasma-assisted synthesis of Al NPs was previously achieved with an inductively coupled plasma (ICP) reactor, but the low production rate and limited tunability of particle size were key barriers to the applications of this material. This work focuses on the application of capacitively coupled plasma (CCP) to achieve improved control over Al NP size and a ten-fold increase in yield. In contrast with many other materials, where NP size is controlled via the gas residence time in the reactor, the Al NP size appeared to depend on the power input to the CCP system. The results indicate that the CCP reactor assembly, with a hydrogen-rich argon/hydrogen plasma, was able to produce Al NPs with diameters that were tunable between 8 and 21 nm at a rate up â¼ 100 mg h-1. X-ray diffraction indicates that a hydrogen-rich environment results in crystalline metal Al particles. The improved synthesis control of the CCP system compared to the ICP system is interpreted in terms of the CCP's lower plasma density, as determined by double Langmuir probe measurements, leading to reduced NP heating in the CCP that is more amenable to NP nucleation and growth.
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Humans have employed cannabis for multiple uses including medicine, recreation, food, and fibre. The various components such as roots, flowers, seeds, and leaves have been utilized to alleviate pain, inflammation, anxiety, and gastrointestinal disorders like nausea, vomiting, diarrhoea, and inflammatory bowel diseases (IBDs). It has occupied a significant space in ethnomedicines across cultures and religions. Despite multi-dimensional uses, the global prohibition of cannabis by the USA through the introduction of the Marijuana Tax Act in 1937 led to prejudice about the perceived risks of cannabis, overshadowing its medicinal potential. Nevertheless, the discovery of tetrahydrocannabinol (THC), the primary psychoactive compound in cannabis, and the endocannabinoid system renewed scientific interest in understanding the role of cannabis in modulating different conditions, including gastrointestinal disorders. Preparations combining cannabidiol and THC have shown promise in mitigating gut symptoms through anti-inflammatory and motility-enhancing effects. This review revisits the ethnomedicinal use of cannabis in gastrointestinal diseases and emphasizes the need for further research to determine optimal dosages, formulations, and safety profiles of cannabis-based medicines. It also underscores the future potential of cannabinoid-based therapies by leveraging the role of the expanded endocannabinoid system, an endocannabinoidome, in the modulation of gastrointestinal ailments.
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Canabinoides , Cannabis , Gastroenteropatias , Alucinógenos , Humanos , Endocanabinoides , Canabinoides/farmacologia , Canabinoides/uso terapêutico , Agonistas de Receptores de Canabinoides , Gastroenteropatias/tratamento farmacológico , Desenvolvimento de Medicamentos , Dronabinol/uso terapêuticoRESUMO
Electrides, which are ionic crystals composed of excess anionic electrons, are of great interest as an exotic material for fundamental research and practical applications in broad fields of science and technology. However, an inherent chemical instability under ambient conditions at room temperature has been a fatal drawback to be addressed. Here, we report that transition metal-rich monochalcogenides are an emerging class of low-dimensional electrides with excellent chemical and thermal stability in air and water at room temperature through a comprehensive exploration of theoretical prediction and experimental verification. We predict new two-dimensional (2D) electrides crystallized in hexagonal P3Ì m1 and P63/mmc structures with strong localization of anionic electrons in a dumbbell shape at the tetrahedral cavity of the interlayer space, which are distinct from the anionic electrons localized at the octahedral cavity in the hexagonal R3Ì m structure of the previous 2D [Ca2N]+·e- and [Y2C]2+·2e- electrides. We successfully synthesized the room-temperature stable [Ti2O]2+·2e-, [Ti2S]2+·2e-, [Zr2S]2+·2e-, and primary solid solution [Hf2SxSe1-x]2+·2e- electrides, showing no structural degradation in air and water. Among them, we found that the synthesized [Ti2S]2+·2e- and [Zr2S]2+·2e- electrides are crystallized in orthorhombic symmetry (Pnnm), showing the feature of a one-dimensional (1D) electride with an anionic electron chain, which has never been reported yet. In addition to the successful finding of new 1D and 2D electrides, we discuss the self-passivation effect-driven chemical stability and the role of anionic electrons in determining the physical properties of the newly discovered electrides.
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Cannabinoid receptor 1 (CB1) activation has been reported to reduce transient receptor potential cation channel subfamily V member 1 (TRPV1)-induced inflammatory responses and is anti-nociceptive and anti-inflammatory in corneal injury. We examined whether allosteric ligands, can modulate CB1 signaling to reduce pain and inflammation in corneal hyperalgesia. Corneal hyperalgesia was generated by chemical cauterization of cornea in wildtype and CB2 knockout (CB2-/-) mice. The novel racemic CB1 allosteric ligand GAT211 and its enantiomers GAT228 and GAT229 were examined alone or in combination with the orthosteric CB1 agonist Δ8-tetrahydrocannabinol (Δ8-THC). Pain responses were assessed following capsaicin (1 µM) stimulation of injured corneas at 6 h post-cauterization. Corneal neutrophil infiltration was also analyzed. GAT228, but not GAT229 or GAT211, reduced pain scores in response to capsaicin stimulation. Combination treatments of 0.5% GAT229 or 1% GAT211 with subthreshold Δ8-THC (0.4%) significantly reduced pain scores following capsaicin stimulation. The anti-nociceptive effects of both GAT229 and GAT228 were blocked with CB1 antagonist AM251, but remained unaffected in CB2-/- mice. Two percent GAT228, or the combination of 0.2% Δ8-THC with 0.5% GAT229 also significantly reduced corneal inflammation. CB1 allosteric ligands could offer a novel approach for treating corneal pain and inflammation.
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Lesões da Córnea/tratamento farmacológico , Dronabinol/análogos & derivados , Hiperalgesia/tratamento farmacológico , Indóis/administração & dosagem , Inflamação/tratamento farmacológico , Receptor CB1 de Canabinoide/metabolismo , Regulação Alostérica/efeitos dos fármacos , Animais , Cauterização , Lesões da Córnea/complicações , Lesões da Córnea/etiologia , Modelos Animais de Doenças , Dronabinol/administração & dosagem , Dronabinol/farmacologia , Sinergismo Farmacológico , Técnicas de Inativação de Genes , Hiperalgesia/metabolismo , Indóis/farmacologia , Inflamação/etiologia , Inflamação/metabolismo , Ligantes , Camundongos , Receptor CB1 de Canabinoide/química , Receptor CB2 de Canabinoide/genética , Transdução de SinaisRESUMO
A static batch culture system inoculated with human faeces was used to determine the influence of essential oil compounds (EOCs) on mixed faecal microbiota. Bacteria were quantified using quantitative PCR of 16S rRNA genes. Incubation for 24 h of diluted faeces from six individuals caused enrichment of Bifidobacterium spp., but proportions of other major groups were unaffected. Thymol and geraniol at 500 p.p.m. suppressed total bacteria, resulting in minimal fermentation. Thymol at 100 p.p.m. had no effect, nor did eugenol or nerolidol at 100 or 500 p.p.m. except for a slight suppression of Eubacterium hallii. Methyl isoeugenol at 100 or 500 p.p.m. suppressed the growth of total bacteria, accompanied by a large fall in the molar proportion of propionate formed. The relative abundance of Faecalibacterium prausnitzii was unaffected except with thymol at 500 p.p.m. The ability of EOCs to control numbers of the pathogen Clostridium difficile was investigated in a separate experiment, in which the faecal suspensions were amended by the addition of pure culture of C. difficile. Numbers of C. difficile were suppressed by thymol and methyl isoeugenol at 500 p.p.m. and to a lesser extent at 100 p.p.m. Eugenol and geraniol gave rather similar suppression of C. difficile numbers at both 100 and 500 p.p.m. Nerolidol had no significant effect. It was concluded from these and previous pure-culture experiments that thymol and geraniol at around 100 p.p.m. could be effective in suppressing pathogens in the small intestine, with no concern for beneficial commensal colonic bacteria in the distal gut.
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Bactérias/efeitos dos fármacos , Fezes/microbiologia , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Adulto , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Infecções Bacterianas/microbiologia , Técnicas de Cultura , Feminino , Fermentação , Humanos , Masculino , Adulto JovemRESUMO
Electrides are a class of materials consisting of non-nuclear excess electrons as quasi-F centers or Farbe centers within a positively charged lattice framework, and have significant applications in the fields of electrochemistry, spintronics, and electrode materials. Using first-principles quantum mechanical calculations, we have demonstrated exotic electronic structures of zirconium-rich electrides, Zr2X (X = O, Se, and Te), and obtained the quantitative values of charge transfer (oxidation states), and projected density of states associated with the localized quasi F-centers. The localized interstitial anionic electrons exhibit significant charge transfer values of approximately -1.88, -2.01, and -1.79 per atom in Zr2O, Zr2Se, and Zr2Te, respectively, and contribute actively in the electronic band structures and density of states at the Fermi level. From the 2D contour plot of the electron localization function (ELF), it has been predicted that the spatial distribution of the quasi-F centers stabilizes in the form of a one-dimensional pattern, with localized ELF sites interconnected with delocalized electron channels. Further, low work-function values of Zr2X, ranging from 2.7-3.4 eV, confirm the electride properties of these binary compounds, promising applications in electro-catalytic oxidations and anode materials in batteries. These unique electronic properties of anionic electrons free from nuclear binding in Zr2X have not been reported yet in the literature.
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The escalating global prevalence of type-2 diabetes (T2D) and obesity necessitates the development of novel oral medications. Agonism at G-protein coupled receptor-119 (GPR119) has been recognized for modulation of metabolic homeostasis in T2D, obesity, and fatty liver disease. However, off-target effects have impeded the advancement of synthetic GPR119 agonist drug candidates. Non-systemic, gut-restricted GPR119 agonism is suggested as an alternative strategy that may locally stimulate intestinal enteroendocrine cells (EEC) for incretin secretion, without the need for systemic drug availability, consequently alleviating conventional class-related side effects. Herein, we report the preclinical acute safety, efficacy, and pharmacokinetics (PK) of novel GPR119 agonist compounds ps297 and ps318 that potentially target gut EEC for incretin secretion. In a proof-of-efficacy study, both compounds demonstrated glucagon-like peptide-1 (GLP-1) secretion capability during glucose and mixed-meal tolerance tests in healthy mice. Furthermore, co-administration of sitagliptin with investigational compounds in diabetic db/db mice resulted in synergism, with GLP-1 concentrations rising by three-fold. Both ps297 and ps318 exhibited low gut permeability assessed in the in-vitro Caco-2 cell model. A single oral dose PK study conducted on healthy mice demonstrated poor systemic bioavailability of both agents. PK measures (mean ± SD) for compound ps297 (Cmax 23 ± 19â¯ng/mL, Tmax range 0.5 - 1â¯h, AUC0-24â¯h 19.6 ± 21â¯h*ng/mL) and ps318 (Cmax 75 ± 22â¯ng/mL, Tmax range 0.25 - 0.5â¯h, AUC0-24â¯h 35 ± 23â¯h*ng/mL) suggest poor oral absorption. Additionally, examinations of drug excretion patterns in mice revealed that around 25â¯% (ps297) and 4â¯% (ps318) of the drugs were excreted through faeces as an unchanged form, while negligible drug concentrations (<0.005â¯%) were excreted in the urine. These acute PK/PD assessments suggest the gut is a primary site of action for both agents. Toxicity assessments conducted in the zebrafish and healthy mice models confirmed the safety and tolerability of both compounds. Future chronic in-vivo studies in relevant disease models will be essential to confirm the long-term safety and efficacy of these novel compounds.
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Diabetes Mellitus Tipo 2 , Obesidade , Receptores Acoplados a Proteínas G , Animais , Humanos , Masculino , Camundongos , Células CACO-2 , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Células Enteroendócrinas/efeitos dos fármacos , Células Enteroendócrinas/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/farmacologia , Camundongos Endogâmicos C57BL , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismoRESUMO
Two-dimensional electrides can acquire topologically non-trivial phases due to intriguing interplay between the cationic atomic layers and anionic electron layers. However, experimental evidence of topological surface states has yet to be verified. Here, via angle-resolved photoemission spectroscopy (ARPES) and scanning tunnelling microscopy (STM), we probe the magnetic Weyl states of the ferromagnetic electride [Gd2C]2+·2e-. In particular, the presence of Weyl cones and Fermi-arc states is demonstrated through photon energy-dependent ARPES measurements, agreeing with theoretical band structure calculations. Notably, the STM measurements reveal that the Fermi-arc states exist underneath a floating quantum electron liquid on the top Gd layer, forming double-stacked surface states in a heterostructure. Our work thus not only unveils the non-trivial topology of the [Gd2C]2+·2e- electride but also realizes a surface heterostructure that can host phenomena distinct from the bulk.
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The adoption of its 2015 constitution has converted Nepal to a federal government while simultaneously resulted in significant reforms of the health system in Nepal in terms of both structure and commitment. In this commentary, we review evidence ranging from health financing to health workforce development to show that the impact of federalization on Nepal's health system and its efforts to achieve equitable and affordable universal health care have been mixed. On the one hand, careful efforts of the federal government to support subnational governments during the transition appears to have avoided serious disruption, subnational governments have successfully taken on the financial burden of the health system, and increase subnational control has allowed more flexible adaptation to changing needs than might have otherwise been possible. On the other hand, financing resource and ability disparities across subnational governments contributes to significant disparities in workforce development, and subnational authorities appear to have underestimated significant health issues (e.g. NCDs) in their budgets. We then provide three recommendations to improve the success of the Nepalese system: (1) to assess whether the services covered by health financing and insurance schemes like the National Health Insurance Program adequately address the needs of the rising burden of NCDs in Nepal, (2) to set clear minimum requirements on key metrics for subnational health systems, and (3) to extend grant programs to address resource disparities.
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Programas Governamentais , Financiamento da Assistência à Saúde , Nepal , Programas Nacionais de Saúde , Recursos HumanosRESUMO
Immune checkpoint blockade (ICB) has become the standard of care for several solid tumors. Multiple combinatorial approaches have been studied to improve therapeutic efficacy. The combination of antiangiogenic agents and ICB has demonstrated efficacy in several cancers. To improve the mechanistic understanding of synergies with these treatment modalities, we performed screens of sera from long-term responding patients treated with ipilimumab and bevacizumab. We discovered a high-titer antibody response against EGF-like repeats and discoidin I-like domains protein 3 (EDIL3) that correlated with favorable clinical outcomes. EDIL3 is an extracellular protein, previously identified as a marker of poor prognosis in various malignancies. Our Tumor Immune Dysfunction and Exclusion analysis predicted that EDIL3 was associated with immune exclusion signatures for cytotoxic immune cell infiltration and nonresponse to ICB. Cancer-associated fibroblasts (CAF) were predicted as the source of EDIL3 in immune exclusion-related cells. Furthermore, The Cancer Genome Atlas Skin Cutaneous Melanoma (TCGA-SKCM) and CheckMate 064 data analyses correlated high levels of EDIL3 with increased pan-fibroblast TGFß response, enrichment of angiogenic signatures, and induction of epithelial-to-mesenchymal transition. Our in vitro studies validated EDIL3 overexpression and TGFß regulation in patient-derived CAFs. In pretreatment serum samples from patients, circulating levels of EDIL3 were associated with circulating levels of VEGF, and like VEGF, EDIL3 increased the angiogenic abilities of patient-derived tumor endothelial cells (TEC). Mechanistically, three-dimensional microfluidic cultures and two-dimensional transmigration assays with TEC endorsed EDIL3-mediated disruption of the lymphocyte function-associated antigen-1 (LFA-1)-ICAM-1 interaction as a possible means of T-cell exclusion. We propose EDIL3 as a potential target for improving the transendothelial migration of immune cells and efficacy of ICB therapy.
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Melanoma , Neoplasias Cutâneas , Humanos , Proteínas de Ligação ao Cálcio/genética , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Melanoma/tratamento farmacológico , Células Endoteliais/metabolismo , Fator A de Crescimento do Endotélio Vascular , Neoplasias Cutâneas/tratamento farmacológico , Fator de Crescimento Transformador beta/metabolismo , Melanoma Maligno CutâneoRESUMO
The microbiota of the intestinal tract plays an important role in colonic health, mediating many effects of dietary components on colonic health and during enteric infections. In the context of the increasing incidence of antibiotic resistance in gut bacteria, complementary therapies are required for the prevention and treatment of enteric infections. Here we report the potential application of essential oils (EO) and pure EO compounds to improve human gut health. Nerolidol, thymol, eugenol and geraniol inhibited growth of the pathogens Escherichia coli O157â:âH7(VT(-)), Clostridium difficile DSM1296, Clostridium perfringens DSM11780, Salmonella typhimurium 3530 and Salmonella enteritidis S1400 at a half-maximal inhibitory concentration (IC(50)) varying from 50 to 500 p.p.m. Most EO showed greater toxicity to pathogens than to commensals. However, the beneficial commensal Faecalibacterium prausnitzii was sensitive to EO at similar or even lower concentrations than the pathogens. The EO showed dose-dependent effects on cell integrity, as measured using propidium iodide, of Gram-positive bacteria. These effects were not strongly correlated with growth inhibition, however, suggesting that cell membrane damage occurred but was not the primary cause of growth inhibition. Growth inhibition of Gram-negative bacteria, in contrast, occurred mostly without cell integrity loss. Principal component analysis showed clustering of responses according to bacterial species rather than to the identity of the EO, with the exception that responses to thymol and nerolidol clustered away from the other EO. In conclusion, the selective effects of some EO might have beneficial effects on gut health if chosen carefully for effectiveness against different species.
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Antibacterianos/farmacologia , Colo/microbiologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/crescimento & desenvolvimento , Humanos , Testes de Sensibilidade MicrobianaRESUMO
Cannabinoid compounds have been shown to exert anti-tumor effects by affecting angiogenesis, invasion, and metastasis. In the present study, we examined the action mechanism by which LYR-8, a novel hexahydrocannabinol analog, exerts anti-angiogenic and anti-tumor activity in human cancer xenografts. In the xenografted tumor tissues, LYR-8 significantly reduced the expression of hypoxia-inducible factor-1 alpha (HIF-1α), a transcription factor responsible for induction of angiogenesis-promoting factors, and its target genes, vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX-2). In HT-29 human colon cancer cells treated with a hypoxia-inducing agent (CoCl(2)), LYR-8 dose-dependently suppressed the induction of HIF-1α and subsequently its targets, VEGF and COX-2. In addition, highly elevated prostaglandin E(2) (PGE(2)) concentrations in CoCl(2)-treated HT-29 cells were also significantly suppressed by LYR-8. However, LYR-8 alone in the absence of CoCl(2) did not alter the basal expression of VEGF and COX-2, or PGE(2) production. Furthermore, LYR-8 effectively suppressed Akt signaling, which corresponded to the suppression of CoCl(2)-induced HIF-1α accumulation. Taken together, LYR-8 exerts anti-tumor effects through the inhibition of Akt and HIF-1α activation, and subsequently suppressing factors regulating tumor microenvironment, such as VEGF and COX-2. These results indicate a novel function of cannabinoid-like compound LYR-8 as an anti-tumor agent with a HIF-1α inhibitory activity.
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Inibidores da Angiogênese/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Dronabinol/análogos & derivados , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Inibidores da Angiogênese/farmacologia , Animais , Galinhas , Membrana Corioalantoide , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Ciclo-Oxigenase 2/metabolismo , Dronabinol/farmacologia , Dronabinol/uso terapêutico , Células HT29 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Carga Tumoral/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Pediocin PA-1 is a class IIa bacteriocin that is particularly effective against the foodborne pathogen Listeria monocytogenes. The loss of activity of PA-1 pediocin due to methionine oxidation is one of the challenges that limit the wider application of the bacteriocin. In this study, we heterologously expressed an oxidation resistant form of pediocin PA-1, i.e., pediocin M31L, and compared its activity to that of native pediocin PA-1 and to penocin A, a pediocin-like bacteriocin that displays a narrower antimicrobial spectrum. Minimal inhibitory concentration assays revealed that pediocin M31L was as effective as PA-1 and more effective than synthetic penocin A against Listeria with negligible activity against a range of obligate anaerobic commensal gut bacterial species. The anti-Listeria activity of these pediocins was also assessed in a simulated human distal colon model assay using the L. monocytogenes, spiked at 6.5 ± 0.13 Log CFU/mL, as a bioindicator. At 24 h, pediocin M31L and penocin A (2.6 µM) reduced Listeria counts to 3.5 ± 0.4 and 3.64 ± 0.62 Log CFU/mL, respectively, whereas Listeria counts were considerably higher, i.e. 7.75 ± 0.43 Log CFU/mL, in the non-bacteriocin-containing control. Ultimately, it was established that synthetic penocin A and the stable pediocin M31L derivative, heterologously produced, display effective anti-Listeria activity in a human gut environment.
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Antibacterianos/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Pediocinas/farmacologia , Antibacterianos/química , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Listeria monocytogenes/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Estrutura Molecular , Oxirredução , Pediocinas/químicaRESUMO
Copper (Cu) nanoparticles (NPs) have received extensive interest owing to their advantageous properties compared with their bulk counterparts. Although the natural oxidation of Cu NPs can be alleviated by passivating the surfaces with additional moieties, obtaining non-oxidized bare Cu NPs in air remains challenging. Here we report that bare Cu NPs with surface excess electrons retain their non-oxidized state over several months in ambient air. Cu NPs grown on an electride support with excellent electron transfer ability are encapsulated by the surface-accumulated excess electrons, exhibiting an ultralow work function of ~3.2 eV. Atomic-scale structural and chemical analyses confirm the absence of Cu oxide moiety at the outermost surface of air-exposed bare Cu NPs. Theoretical energetics clarify that the surface-accumulated excess electrons suppress the oxygen adsorption and consequently prohibit the infiltration of oxygen into the Cu lattice, provoking the endothermic reaction for oxidation process. Our results will further stimulate the practical use of metal NPs in versatile applications.
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Vascular inflammation has been implicated in the progression of cardiovascular diseases such as atherosclerosis. In the present study, we found that HMC05, an extract from eight different herbal mixtures, dose-dependently inhibited tumor necrosis factor-α (TNF-α)-induced adhesion of monocytes to endothelial cells. Such inhibitory effect of HMC05 correlated with suppressed expression of monocyte chemoattractant protein-1, CC chemokine receptor 2, vascular cell adhesion molecule-1 and intercellular cell adhesion molecule-1. In addition, HMC05 significantly inhibited production of reactive oxygen species (ROS) and nuclear factor (NF)-κB activation by TNF-α. Those inhibitory effects of HMC05 (1-10 µg mL(-1)) on the TNF-α-induced inflammatory event was similar to those of berberine (1-10 µM), which is a major component of HMC05 and one of herbal compounds known to have vasorelaxing and lipid-lowering activities. However, berberine significantly reduced the viability of HUVECs in a time- and concentration-dependent manner. In contrast, HMC05 (1-10 µg ml(-1)) did not affect the cell viability for up to 48 h treatment. In conclusion, we propose that HMC05 may be a safe and potent herbal formula against vascular inflammation, and its action may be attributable to the inhibition of ROS- and NF-κB-dependent expression of adhesion molecules and chemokines.
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The human intestinal commensal microbiota and associated metabolic products have long been regarded as contributors to host health. As the identity and activities of the various members of this community have become clearer, newly identified health-associated bacteria, such as Faecalibacterium prausnitzii, Akkermansia muciniphila, Ruminococcus bromii and Roseburia species, have emerged. Notably, the abundance of many of these bacteria is inversely correlated to several disease states. While technological and regulatory hurdles may limit the use of strains from these taxa as probiotics, it should be possible to utilize prebiotics and other dietary components to selectively enhance their growth in situ. Dietary components of potential relevance include well-established prebiotics, such as galacto-oligosaccharides, fructo-oligosaccharides and inulin, while other putative prebiotics, such as other oligosaccharides, polyphenols, resistant starch, algae and seaweed as well as host gut metabolites such as lactate and acetate, may also be applied with the aim of selectively and/or differentially affecting the beneficial bacterial community within the gastrointestinal environment. The present review provides an overview of the dietary components that could be applied in this manner.
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Bactérias/metabolismo , Microbioma Gastrointestinal , Trato Gastrointestinal , Prebióticos/microbiologia , Probióticos/metabolismo , Bactérias/classificação , Bactérias/isolamento & purificação , Dieta , Suplementos Nutricionais , Microbioma Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Humanos , Minerais/metabolismo , Oligossacarídeos/metabolismo , Polifenóis/metabolismo , Probióticos/uso terapêutico , Alga MarinhaRESUMO
Staphylococcus epidermidis is a commensal species that has been increasingly identified as a nosocomial agent. Despite the interest, little is known about the ability of S. epidermidis isolates to adapt to different ecological niches through comparisons at genotype or phenotype levels. One niche where S. epidermidis has been reported is the human gut. Here, we present three S. epidermidis strains isolated from feces and show that they are not phylogenetically distinct from S. epidermidis isolated from other human body sites. Both gut and skin strains harbored multiple genes associated with biofilm formation and showed similar levels of biofilm formation on abiotic surfaces. High-throughput physiological tests using the BIOLOG technology showed no major metabolic differences between isolates from stool, skin, or cheese, while an isolate from bovine mastitis showed more phenotypic variation. Gut and skin isolates showed the ability to metabolize glycine-conjugated bile acids and to grow in the presence of bile, but the gut isolates exhibited faster anaerobic growth compared to isolates of skin origin.
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NAD[P]H:quinone oxidoreductase 1 (NQO1) regulates cell fate decisions in response to stress. Oxidative stress supports cancer maintenance and progression. Previously we showed that knockdown of NQO1 (NQO1low) prostate cancer cells upregulate pro-inflammatory cytokines and survival under hormone-deprived conditions. Here, we tested the ability of NQO1low cells to form tumors. We found NQO1low cells form aggressive tumors compared with NQO1high cells. Biopsy specimens and circulating tumor cells showed biochemical recurrent prostate cancer was associated with low NQO1. NQO1 silencing was sufficient to induce SMAD-mediated TGFß signaling and mesenchymal markers. TGFß treatment decreased NQO1 levels and induced molecular changes similar to NQO1 knockdown cells. Functionally, NQO1 depletion increased migration and sensitivity to oxidative stress. Collectively, this work reveals a possible new gatekeeper role for NQO1 in counteracting cellular plasticity in prostate cancer cells. Further, combining NQO1 with TGFß signaling molecules may serve as a better signature to predict biochemical recurrence.
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Plasticidade Celular/genética , NAD(P)H Desidrogenase (Quinona)/genética , Estresse Oxidativo , Neoplasias da Próstata/fisiopatologia , Fator de Crescimento Transformador beta/genética , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Nus , NAD(P)H Desidrogenase (Quinona)/metabolismo , Neoplasias da Próstata/genética , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima/fisiologiaRESUMO
An aqueous extract of Cornus kousa Burg. leaves (ACK) that contained high amount of polyphenols showed significant antioxidant activity against diphenylpicrylhydrazyl (DPPH) radicals and TNF-alpha-generated reactive oxygen species. ACK at concentrations of 10 and 50 microg/mL significantly inhibited TNF-alpha-induced adhesion of U937 pre-monocytic cells to HT-29 colon epithelial cells in a concentration-dependent manner. The reduced adhesion by ACK correlated with the suppressed expressions of monocyte chemoattractant protein (MCP)-1 and interleukin (IL)-8, the major inflammatory bowel disease (IBD)-associated chemokines. Moreover, ACK significantly suppressed TNF-alpha-induced translocation of redox-sensitive nuclear factor (NF)-kappaB as well as degradation of cytosolic I-kappaBalpha. The effective concentrations of ACK were much lower than that of 5-aminosalicylic acid (3.06 mg/mL), which is an active metabolite of sulfasalazine, a well-known drug used in the treatment of IBD. The results indicate that ACK may provide a potential benefit for the prevention and treatment of inflammatory diseases such as IBD.