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1.
Environ Toxicol ; 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38366283

RESUMO

RNA m6 methyladenosine (m6A) modifications impact tumor biology and immune processes, particularly in hepatocellular malignant tumors. Using a consensus clustering algorithm on 371 hepatocellular carcinoma (HCC) samples, we identified three m6A-modified subtypes and correlated them with positive tumor microenvironment (TME) markers for distinct immune phenotypes. Stratifying patients based on m6A scores revealed a low presentation group with better immune penetration, lower tumor mutation load, and increased expression of immune checkpoint markers like CTLA-4 and PD-1, suggesting enhanced responsiveness to immunization therapy. A machine-learning model of 23 m6A genes was constructed. Single-cell analysis revealed a surprising enrichment of IGFBP3 in astrocytes, prompting the exploration of associated signaling pathways. Experimental verification shows that IGFBP3 is significantly enhanced in normal tissues, while immunohistochemical analysis shows that its expression is lower in tumor tissues, indicating its protective effect in HCC and a good prognosis. Importantly, high IGFBP3 expression is associated with better outcomes in patients receiving immunotherapy. Moreover, cytotoxic T lymphocyte (CTL) experiments have confirmed that high expression of IGFBP3 is associated with stronger T cell-killing ability. In summary, the comprehensive evaluation of m6A modification, immune characteristics, and single-cell analysis in this study not only revealed the TME of HCC but also made significant contributions to the progress of personalized HCC immunotherapy targeting IGFBP3. This study provides a solid theoretical foundation for clinical translation and emphasizes its potential impact on developing effective treatment strategies.

2.
J Environ Sci (China) ; 129: 139-151, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36804230

RESUMO

This study investigated the enhancement effects of dissolved carbonates on the peroxymonosulfate-based advanced oxidation process with CuS as a catalyst. It was found that the added CO32- increased both the catalytic activity and the stability of the catalyst. Under optimized reaction conditions in the presence of CO32-, the degradation removal of 4-methylphenol (4-MP) within 2 min reached 100%, and this was maintained in consecutive multi-cycle experiments. The degradation rate constant of 4-MP was 2.159 min-1, being 685% greater than that in the absence of CO32- (0.315 min-1). The comparison of dominated active species and 4-MP degradation pathways in both CO32--free and CO32--containing systems suggested that more CO3•-/1O2 was produced in the case of CO32-deducing an electron transfer medium, which tending to react with electron-rich moieties. Meanwhile, Characterization by X-ray photoelectron spectroscopic and cyclic voltammetry measurement verified CO32- enabled the effective reduction of Cu2+ to Cu+. By investigating the degradation of 11 phenolics with different substituents, the dependence of degradation kinetic rate constant of the phenolics on their chemical structures indicated that there was a good linear relationship between the Hammett constants σp of the aromatic phenolics and the logarithm of k in the CO32--containing system. This work provides a new strategy for efficient removal of electron-rich moieties under the driving of carbonate being widely present in actual water bodies.


Assuntos
Fenóis , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Peróxidos , Carbonatos/química
3.
Pharmacol Res ; 186: 106530, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36349593

RESUMO

The interaction between mitochondria and gut microbiota plays a critical role in intestinal physiological homeostasis. In this kind of homeostasis, intestinal epithelial hypoxia helps microbiota to be dominated by obligate anaerobes, who provide their benefit metabolites for the host, such as short chain fatty acids (SCFAs). In addition, emerging studies suggest that microbial signals to the mitochondria of intestinal epithelial cells (IECs) could alter mitochondrial ultrastructure and its metabolic function, induce inflammasome activation and disrupt epithelial hypoxia. Conditions that alter the mitochondria could lead to intestinal epithelium inflammation and oxygenation, both of which would drive an expansion of facultative anaerobes and exacerbate the imbalance of mitochondria-microbiota crosstalk. This phenomenon has proved to be associated with the pathogenesis of gastrointestinal (GI) diseases, including inflammatory bowel disease (IBD) and colorectal cancer (CRC). Therefore, in this review, we summarized the recent process on the interaction between mitochondria of IECs and gut microbiota in the case of both GI physiological homeostasis and diseases, and potential therapeutic interventions targeting mitochondria-microbiota crosstalk in GI diseases.


Assuntos
Gastroenteropatias , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Microbiota , Humanos , Mucosa Intestinal/metabolismo , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/metabolismo , Mitocôndrias/metabolismo , Hipóxia/metabolismo
4.
Heart Surg Forum ; 25(1): E001-E007, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35238311

RESUMO

OBJECTIVE: Levosimendan is a novel drug often used to treat heart failure. We aimed to explore the effects of levosimendan preconditioning on left ventricular remodeling (LVR) after myocardial reperfusion in acute myocardial infarction (AMI) patients receiving the percutaneous coronary intervention (PCI). METHODS: A total of 258 AMI patients treated from January 2018 to September 2020 were randomly divided into control and observation groups. Based on conventional drug therapy, levosimendan was given 30 min before PCI for the observation group, and dobutamine was intravenously injected for the control group. Baseline data, thrombolysis in myocardial infarction (TIMI) blood flow grade, myocardial injury markers, and LVR indices were compared, and the influencing factors for LVR were analyzed. RESULTS: After treatment, various degrees of blood perfusion were found, and the TIMI grade was better than that before treatment in both groups (P < .05). The levels of aspartate aminotransferase, creatine kinase-MB, cardiac troponin T, and brain natriuretic peptide (BNP) declined in both groups, more significantly in the observation group (P < .05). Left ventricular end-systolic diameter, left ventricular end-diastolic diameter and left ventricular end-diastolic volume declined, whereas left ventricular ejection fraction rose in both groups, more significantly in the observation group (P < .05). Age and BNP were risk factors for LVR, whereas levosimendan preconditioning was a protective factor (P < .05). CONCLUSION: Levosimendan preconditioning can protect cardiac function and promote the recovery of the left ventricular structure. Age and BNP are risk factors for LVR after myocardial reperfusion in AMI patients undergoing PCI, and levosimendan preconditioning is a protective factor.


Assuntos
Infarto do Miocárdio , Intervenção Coronária Percutânea , Humanos , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/cirurgia , Reperfusão Miocárdica , Simendana/uso terapêutico , Volume Sistólico , Função Ventricular Esquerda , Remodelação Ventricular
5.
Pharmacol Res ; 165: 105439, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33493658

RESUMO

The gut microbiota is recognized as a promising therapeutic target for anxiety. Berberine (BBR) has shown efficacy in the treatment of diseases such as postmenopausal osteoporosis, obesity, and type 2 diabetes through regulating the gut microbiota. However, the effects of BBR on postmenopausal anxiety are still unclear. The purpose of the study is to test whether BBR ameliorates anxiety by modulating intestinal microbiota under estrogen-deficient conditions. Experimental anxiety was established in specific pathogen-free (SPF) ovariectomized (OVX) rats, which were then treated with BBR for 4 weeks before undergoing behavioral tests. Open field and elevated plus maze tests demonstrated that BBR treatment significantly ameliorated anxiety-like behaviors of OVX rats compared with vehicle-treated counterparts. Moreover, as demonstrated by 16S rRNA sequencing and liquid chromatography/mass spectrometry (LC/MS) analysis, BBR-treated OVX rats harbored a higher abundance of beneficial gut microbes, such as Bacteroides, Bifidobacterium, Lactobacillus, and Akkermansia, and exhibited increased equol generation. Notably, gavage feeding of BBR had no significant anti-anxiety effects on germ-free (GF) rats that underwent ovariectomy, whereas GF rats transplanted with fecal microbiota from SPF rats substantially phenocopied the donor rats in terms of anxiety-like symptoms and isoflavone levels. This study indicates that the gut microbiota is critical in the treatment of ovariectomy-aggravated anxiety, and that BBR modulation of the gut microbiota is a promising therapeutic strategy for treating postmenopausal symptoms of anxiety.


Assuntos
Ansiedade/tratamento farmacológico , Ansiedade/metabolismo , Berberina/uso terapêutico , Equol/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Ovariectomia/efeitos adversos , Animais , Ansiedade/etiologia , Berberina/farmacologia , Transplante de Microbiota Fecal/métodos , Feminino , Microbioma Gastrointestinal/fisiologia , Ratos , Ratos Sprague-Dawley
6.
Acta Pharmacol Sin ; 42(11): 1821-1833, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33558654

RESUMO

Accumulating evidence shows that agents targeting gut dysbiosis are effective for improving symptoms of irritable bowel syndrome (IBS). However, the potential mechanisms remain unclear. In this study we investigated the effects of berberine on the microbiota-gut-brain axis in two rat models of visceral hypersensitivity, i.e., specific pathogen-free SD rats subjected to chronic water avoidance stress (WAS) and treated with berberine (200 mg· kg-1 ·d-1, ig, for 10 days) as well as germ-free (GF) rats subjected to fecal microbiota transplantation (FMT) from a patient with IBS (designated IBS-FMT) and treated with berberine (200 mg· kg-1 ·d-1, ig, for 2 weeks). Before the rats were sacrificed, visceral sensation and depressive behaviors were evaluated. Then colonic tryptase was measured and microglial activation in the dorsal lumbar spinal cord was assessed. The fecal microbiota was profiled using 16S rRNA sequencing, and short chain fatty acids (SCFAs) were measured. We showed that berberine treatment significantly alleviated chronic WAS-induced visceral hypersensitivity and activation of colonic mast cells and microglia in the dorsal lumbar spinal cord. Transfer of fecal samples from berberine-treated stressed donors to GF rats protected against acute WAS. FMT from a patient with IBS induced visceral hypersensitivity and pro-inflammatory phenotype in microglia, while berberine treatment reversed the microglial activation and altered microbial composition and function and SCFA profiles in stools of IBS-FMT rats. We demonstrated that berberine did not directly influence LPS-induced microglial activation in vitro. In both models, several SCFA-producing genera were enriched by berberine treatment, and positively correlated to the morphological parameters of microglia. In conclusion, activation of microglia in the dorsal lumbar spinal cord was involved in the pathogenesis of IBS caused by dysregulation of the microbiota-gut-brain axis, and the berberine-altered gut microbiome mediated the modulatory effects of the agent on microglial activation and visceral hypersensitivity, providing a potential option for the treatment of IBS.


Assuntos
Berberina/uso terapêutico , Eixo Encéfalo-Intestino/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Microglia/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Dor Visceral/tratamento farmacológico , Animais , Berberina/farmacologia , Eixo Encéfalo-Intestino/fisiologia , Linhagem Celular , Transplante de Microbiota Fecal/métodos , Microbioma Gastrointestinal/fisiologia , Humanos , Síndrome do Intestino Irritável/tratamento farmacológico , Síndrome do Intestino Irritável/metabolismo , Masculino , Camundongos , Microglia/metabolismo , Ratos , Ratos Sprague-Dawley , Medula Espinal/metabolismo , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/metabolismo , Dor Visceral/metabolismo
7.
Sensors (Basel) ; 21(15)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34372463

RESUMO

In this paper we study the code design problem of a new form of linear frequency modulation phase-coded (LFM-PC) hybrid signal with wide Doppler tolerance based on a range-Doppler discrete ambiguity function (DAF) to get better detection performance and anti-jamming capability. The DAF of the LFM-PC inter pulse signal is derived within the Doppler tolerance. Two optimization models are established. One is single pulse sequence design (SSD) for Doppler tolerance extension based on minimum integral normalized sidelobe level (INSL); the other is multi pulse sequence set design (MSSD) for signal orthogonality based on the minimizing sum of the normalized DAF sidelobe (NDAFSL) and discrete cross ambiguity function (DCAF). Two low-complexity signal optimization methods based on alternating direction method of multiplier (ADMM) are proposed, respectively. The simulation results show that the optimized signals have either wide Doppler tolerance or good orthogonal performance, and the optimization methods (i.e., SSD-ADMM and MSSD-ADMM) have the characteristics of fast convergence speed and low operation amount.

8.
Sensors (Basel) ; 21(23)2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34883919

RESUMO

In this paper, a new radar signal modulated with a hybrid of the frequency shift keying (FSK) and the phase shift keying (PSK) signal-i.e., the FSK-PSK signal-is studied. Different phase encoding sequences are used to modulate the sub-pulses to obtain lower sidelobe levels and ensure signal orthogonality. In addition, to counter intra-pulse slice repeater jamming of specific length generated by the enemy jammer, an orthogonal waveform made of sub-pulses of equal length based on the FSK-PSK modulation scheme is designed. The simulation results show that the optimized discrete phase encoding sequence can significantly enhance the orthogonality of the sub-pulse in the FSK-PSK signal and effectively suppress the slice repeater jamming. Two algorithms are proposed: (1) the low sidelobe waveform optimization algorithm based on ADMM (LSW-ADMM); and (2) the anti-slice-repeater-jamming algorithm based on ADMM (ASRJ-ADMM). Both algorithms exhibit fast convergence speed and low computational complexity.

9.
Sensors (Basel) ; 21(24)2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34960364

RESUMO

By repeatedly sampling, storing, and retransmitting parts of the radar signal, interrupted sampling repeater jamming (ISRJ) based on digital radio frequency memory (DRFM) can produce a train of secondary false targets symmetrical to the main false target, threatening to mislead or deceive the victim radar system. This paper proposes a computationally-effective method to estimating the parameters for ISRJ by resorting to the framework of alternating direction method of multipliers (ADMM). Firstly, the analytical form of pulse compression is derived. Then, for the purpose of estimating the parameters of ISRJ, the original problem is transformed into a nonlinear integer optimization model with respect to a window vector. On this basis, the ADMM is introduced to decompose the nonlinear integer optimization model into a series of sub-problems to estimate the width and number of ISRJ's sample slices. Finally, the numerical simulation results show that, compared with the traditional time-frequency (TF) method, the proposed method exhibits much better performance in accuracy and stability.

10.
Entropy (Basel) ; 23(9)2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34573794

RESUMO

Space-time adaptive processing (STAP) techniques have been motivated as a key enabling technology for advanced airborne radar applications. In this paper, a slow-time code design is considered for the STAP technique in airborne radar, and the principle for improving signal-to-clutter and noise ratio (SCNR) based on slow-time coding is given. We present two algorithms for the optimization of transmitted codes under the energy constraint on a predefined area of spatial-frequency and Doppler-frequency plane. The proposed algorithms are constructed based on convex optimization (CVX) and alternating direction (AD), respectively. Several criteria regarding parameter selection are also given for the optimization process. Numerical examples show the feasibility and effectiveness of the proposed methods.

11.
Proc Biol Sci ; 287(1929): 20200358, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32576116

RESUMO

Climate change is one of the most pervasive threats to biodiversity globally, yet the influence of climate relative to other drivers of species depletion and range contraction remain difficult to disentangle. Here, we examine climatic and non-climatic correlates of giant panda (Ailuropoda melanoleuca) distribution using a large-scale 30 year dataset to evaluate whether a changing climate has already influenced panda distribution. We document several climatic patterns, including increasing temperatures, and alterations to seasonal temperature and precipitation. We found that while climatic factors were the most influential predictors of panda distribution, their importance diminished over time, while landscape variables have become relatively more influential. We conclude that the panda's distribution has been influenced by changing climate, but conservation intervention to manage habitat is working to increasingly offset these negative consequences.


Assuntos
Mudança Climática , Ursidae , Animais , Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Espécies em Perigo de Extinção , Temperatura
12.
Exp Cell Res ; 383(1): 111497, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31301291

RESUMO

TGF-ß-activated kinase 1 (TAK1) plays a pivotal role in Toll-like receptor (TLR) signaling pathway. However, the mechanisms controlling its activity remain poorly understood. Here, we show that leucine-rich repeat containing 62 (LRRC62), a previously uncharacterized protein, negatively regulates TLR signaling by targeting TAK1. Expression of LRRC62 inhibits the TLRs-induced production of pro-inflammatory cytokine, whereas deficiency in LRRC62 enhances the activation of NF-κB and MAPK signaling and increases the production of pro-inflammatory cytokines. Mechanically, LRRC62 functions as an adaptor to recruit deubiquitinase CYLD to TAK1, thus inhibits the K63-linked poly-ubiquitination and activation of TAK1. Together, our findings uncover an unrecognized mechanism by which LRRC62 antagonizes the activation of TAK1 in a CYLD-mediated deubiquitination-dependent manner, thereby balancing Toll-like receptor signaling to avert overzealous inflammation.


Assuntos
Enzima Desubiquitinante CYLD/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Proteínas de Membrana/metabolismo , NF-kappa B/metabolismo , Receptores Toll-Like/metabolismo , Ubiquitinação , Enzima Desubiquitinante CYLD/genética , Células HEK293 , Humanos , MAP Quinase Quinase Quinases/genética , Proteínas de Membrana/genética , NF-kappa B/genética , Ligação Proteica , Proteólise , Transdução de Sinais , Receptores Toll-Like/genética
13.
BMC Urol ; 20(1): 95, 2020 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-32652967

RESUMO

BACKGROUND: Horseshoe kidney (HSK) is a common renal fusion anomaly, occurring in about 1 in 400-600 individuals. In addition, the incidence of duplicated collecting system is about 0.8%. CASE PRESENTATION: This report documents an extremely rare case, which was treated by multiple procedures in the same operative session to accomplish laparoscopic amputation of the HSK isthmus, resection of duplicate kidney and ureteroscopic lithotripsy. CONCLUSION: Results showed that minimally invasive surgery with use of multiple endoscopes may be a feasible choice for this patient population with complicated comorbid renal conditions.


Assuntos
Anormalidades Múltiplas/cirurgia , Rim/anormalidades , Rim/cirurgia , Laparoscopia , Cálculos Ureterais/cirurgia , Ureteroscopia , Adulto , Terapia Combinada , Rim Fundido/complicações , Humanos , Masculino , Cálculos Ureterais/complicações
14.
Lasers Med Sci ; 35(5): 1025-1034, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32006262

RESUMO

To explore the advantages and limitations of holmium laser resection of the bladder tumor (HOLRBT) versus standard transurethral resection of the bladder tumor (TURBT) in the treatment of non-muscle-invasive bladder cancer (NMIBC), the eligible studies were selected from the following databases: PubMed, Cochrane Library, and Embase. Studies comparing HOLRBT and TURBT for patients with NMIBC were included. The outcomes of interest were time of operation, catheterization and hospitalization, rates of recurrence, and perioperative complications, including obturator nerve reflex, bladder perforation, bladder irritation, and urethral stricture. Results of all data were compared and analyzed by Review Manager 5.3. A total of 9 comparative studies were finally included for this analysis. Pooled data demonstrated that HOLRBT significantly reduced the time to catheterization and hospitalization, the rate of recurrence in 2 years of follow-up, obturator nerve reflex, bladder perforation, and bladder irritation, compared with those in TURBT, respectively. However, no significant difference found between HOLRBT and TURBT in the time of operation, rate of recurrence in 1-year follow-up, and urethral stricture. The results of this research reached that HOLRBT would be a better choice than TURBT for patients with NMIBC.


Assuntos
Lasers de Estado Sólido/uso terapêutico , Músculos/patologia , Neoplasias da Bexiga Urinária/cirurgia , Procedimentos Cirúrgicos Urológicos , Idoso , Cateterismo , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Complicações Pós-Operatórias/etiologia , Viés de Publicação , Resultado do Tratamento , Estreitamento Uretral/cirurgia , Neoplasias da Bexiga Urinária/patologia
15.
Sheng Li Xue Bao ; 72(3): 361-370, 2020 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-32572433

RESUMO

Stress is the non-specific systemic response that occurs when the body is stimulated by various factors, and it can affect multiple systems of the body. Recent studies have shown that gut microbiota is an essential part of human microecology, and plays a pivotal role in keeping the body healthy. Stress can result in gut dysbiosis by affecting the function of intestinal mucosal barrier, intestinal immune and gastrointestinal motility. This article reviewed the alteration of gut microbiota caused by stress and the possible mechanisms involved.


Assuntos
Microbioma Gastrointestinal , Disbiose , Motilidade Gastrointestinal , Humanos , Mucosa Intestinal
16.
Langmuir ; 35(15): 5130-5139, 2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-30907594

RESUMO

The interesting properties of water molecules confined in a two-dimensional (2D) environment have aroused great attention. However, the study of 2D-confined water at the hydrophilic-hydrophilic interface is largely unexplored due to the lack of appropriate system. In this work, the behavior of water molecules confined between an atomically thin mica nanosheet and a hydrophilic SiO2/Si substrate was investigated using an atomic force microscope in detail at ambient conditions. The confined water molecules aggregated as droplets when the relative humidity (RH) of the environment was 11%. A large-area 2D water film with a uniform thickness of ∼2 nm was observed when the mica flake was incubated at 33% RH for 1 h before being mechanically exfoliated on a SiO2/Si substrate. Interestingly, the water film showed ordered edges with a predominant angle of 120°, which was the same with the lattice orientation of the mica nanosheet on top of it. The water film showed a fluidic behavior at the early stage and reached a stable state after 48 h under ambient conditions. The surface properties of the upper mica nanosheet and the underlying substrate played a crucial role in manipulating the behavior of confined water molecules. When the surface of the upper mica nanosheet was modified by Na+, Ni2+, and aminopropyltriethoxysilane (APS), only some small water droplets were observed instead of a water film. The surface of the underlying SiO2/Si substrate was functionalized by hydrophilic APS and hydrophobic octadecyltrimethoxysiliane (OTS). The small water droplets were imaged on a hydrophobic OTS-SiO2/Si substrate, while the water film with regular edges was maintained on a hydrophilic APS-SiO2/Si substrate. Our results might provide an alternative molecular view for investigating structures and properties of confined water molecules in 2D environments.

17.
J Gastroenterol Hepatol ; 34(8): 1368-1376, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30402954

RESUMO

BACKGROUND AND AIM: Emerging evidence indicates that psychological stress is involved in the pathogenesis of irritable bowel syndrome, which is characterized by visceral hypersensitivity and may be accompanied by gut dysbiosis. However, how such stress contributes to the development of visceral hypersensitivity is incompletely understood. Here, we aimed to investigate the influence that stress-induced microbial changes exert on visceral sensitivity, as well as the possible underlying mechanisms associated with this effect. METHODS: Male Sprague-Dawley rats underwent chronic water avoidance stress (WAS) to induce visceral hypersensitivity. Visceral sensitivity, colonic tight junction protein expression, and short-chain fatty acids of cecal contents were measured. Fecal samples were collected to characterize microbiota profiles. In a separate study, oral gavage of Roseburia in WAS rats was conducted to verify its potential role in the effectiveness on visceral hypersensitivity. RESULTS: Repeated WAS caused visceral hypersensitivity, altered fecal microbiota composition and function, and decreased occludin expression in the colon. Stressed rats exhibited reduced representation of pathways involved in the metabolism of butyrate and reduced abundance of several operational taxonomic units associated with butyrate-producing bacteria, such as Lachnospiraceae. Consistently, supplementation with Roseburia hominis, a species belonging to Lachnospiraceae, significantly increased cecal butyrate content. Moreover, Roseburia supplementation alleviated visceral hypersensitivity and prevented the decreased expression of occludin. CONCLUSIONS: Reduction in the abundance of butyrate-producing Lachnospiraceae, which is beneficial for the intestinal barrier, was involved in the formation of visceral hypersensitivity. R. hominis is a potential probiotic for treating stress-induced visceral hypersensitivity.


Assuntos
Butiratos/metabolismo , Clostridiales/metabolismo , Colo/microbiologia , Hiperalgesia/prevenção & controle , Limiar da Dor , Probióticos/farmacologia , Estresse Psicológico/complicações , Dor Visceral/prevenção & controle , Animais , Colo/metabolismo , Modelos Animais de Doenças , Fezes/microbiologia , Microbioma Gastrointestinal , Hiperalgesia/etiologia , Hiperalgesia/microbiologia , Hiperalgesia/fisiopatologia , Masculino , Ocludina/metabolismo , Percepção da Dor , Ratos Sprague-Dawley , Junções Íntimas/metabolismo , Junções Íntimas/microbiologia , Dor Visceral/etiologia , Dor Visceral/microbiologia , Dor Visceral/fisiopatologia
18.
Nanomaterials (Basel) ; 14(4)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38392712

RESUMO

As one of the key features of two-dimensional (2D) layered materials, stacking order has been found to play an important role in modulating the interlayer interactions of 2D materials, potentially affecting their electronic and other properties as a consequence. In this work, ultralow-frequency (ULF) Raman spectroscopy, electrostatic force microscopy (EFM), and high-resolution atomic force microscopy (HR-AFM) were used to systematically study the effect of stacking order on the interlayer interactions as well as electrostatic screening of few-layer polymorphic molybdenum disulfide (MoS2) and molybdenum diselenide (MoSe2) nanosheets. The stacking order difference was first confirmed by measuring the ULF Raman spectrum of the nanosheets with polymorphic stacking domains. The atomic lattice arrangement revealed using HR-AFM also clearly showed a stacking order difference. In addition, EFM phase imaging clearly presented the distribution of the stacking domains in the mechanically exfoliated nanosheets, which could have arisen from electrostatic screening. The results indicate that EFM in combination with ULF Raman spectroscopy could be a simple, fast, and high-resolution method for probing the distribution of polymorphic stacking domains in 2D transition metal dichalcogenide materials. Our work might be promising for correlating the interlayer interactions of TMDC nanosheets with stacking order, a topic of great interest with regard to modulating their optoelectronic properties.

19.
Front Psychiatry ; 15: 1279266, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38352653

RESUMO

Objective: Potential causal associations between psychiatric disorders and irritable bowel syndrome have been demonstrated in observational studies; however, these studies are susceptible to underlying confounding and reverse causation biases. We aimed to assess the causal effects of psychiatric disorders on irritable bowel syndrome (IBS) and the potential mediators from a genetic perspective by conducting a Mendelian randomization (MR) study with mediation analysis. Method: Genetic instruments associated with psychiatric disorders, potential mediators, and IBS were obtained from large-scale genome-wide association studies (GWAS). Three MR methods - the inverse-variance weighted (IVW) method, MR-Egger method, and weighted median method, were used to investigate causal association estimates. Heterogeneity among different genetic instrumental variables (IVs) was assessed using Q tests. Additionally, the MR-PRESSO and MR-Pleiotropy methods were used to verify horizontal pleiotropy and detect outliers that might bias the results, which were removed from further analysis. Consequently, we used MR mediation analysis to investigate potential mediators in the causal associations between psychiatric disorders and IBS. Results: MR provided evidence of the causal effects of genetically predicted broad depression, major depressive disorder (MDD), anxiety disorder, post-traumatic stress disorder (PTSD), and schizophrenia on IBS. The results of MR mediation analysis demonstrated that the reduction in acetate levels mediated 12.6% of the effects of broad depression on IBS; insomnia mediated 16.00%, 16.20%, and 27.14% of the effects of broad depression, MDD, and PTSD on IBS, respectively; and the increase in blood ß-hydroxybutyrate levels mediated 50.76% of the effects of schizophrenia on IBS. Conclusion: Our study confirmed the brain-gut axis involvement and potential modulators in the pathophysiology of psychiatric disorder-induced IBS from a genetic perspective, and suggests potential therapeutic targets for the disrupted brain-gut axis.

20.
iScience ; 27(6): 110051, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904067

RESUMO

Scent marking sites served as a primary means of chemical communication for giant pandas, enabling intraspecific communication. We integrated metabolomics and high-throughput sequencing techniques to examine the non-targeted metabolome and microbial community structure of scent marking sites and feces in the field. Integrative analysis revealed a more comprehensive array of chemical compounds compared to previous investigations, including ketones, acids, heterocycles, alcohols, and aldehydes. Notably, specific compounds such as 2-decenal, (E)-, octanal, decanal, L-α-terpineol, vanillin, and nonanal emerged as potential key players in scent signaling. Intriguingly, our study of the microbial domain identified dominant bacterial species from the Actinobacteria, Bacteroidetes, and Proteobacteria phyla, likely orchestrating metabolic processes at scent marking sites. Comparative analyses showed, for the first time, that feces do not share the same functions as scent markers, indicating distinct functional roles. This research deepens scientific understanding of chemical communication in wild pandas.

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