Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 50
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Int J Biol Macromol ; 275(Pt 1): 133427, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38936586

RESUMO

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is an disease characterized by pulmonary edema and widespread inflammation, leading to a notably high mortality rate. The dysregulation of both pro-inflammatory and anti-inflammatory systems, results in cytokine storm (CS), is intricately associated with the development of ALI/ARDS. Tetrastigma hemsleyanum polysaccharide (THP) exerts remarkable anti-inflammatory and immunomodulatory effects against the disease, although its precise role in pathogenesis remains unclear. In the present study, an ALI/ARDS model was established using bacterial lipopolysaccharides. THP administration via aerosol inhalation significantly mitigated lung injury, reduced the number of inflammatory cells, and ameliorated glycerophospholipid metabolism. Furthermore, specific CS-related pathways were investigated by examining the synergy between tumor necrosis factor-α and interferon-γ used to establish CS models. The results indicated that THP effectively decreased inflammatory damage and cell death. The RNA sequencing revealed the involvement of the Janus kinase (JAK) 2-signal transducers and activators of transcription (STAT) signaling pathway in exerting the mentioned effects. Additionally, THP inhibited the activation of the JAK-STAT pathway, thereby alleviating the CS both in vivo and in vitro. Overall, THP exhibited marked therapeutic potential against ALI/ARDS and CS, primarily by targeting the IFN-γ-JAK2/STAT signaling pathway.

2.
Int Immunopharmacol ; 137: 112404, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38851163

RESUMO

Ulcerative colitis (UC) is characterized by a chronic and protracted course and often leads to a poor prognosis. Patients with this condition often experience postoperative complications, further complicating the management of their condition. Tetrastigma hemsleyanum polysaccharide (THP) has demonstrated considerable potential as a treatment for inflammatory bowel disease. However, its underlying mechanism in the treatment of UC remains unclear. This study systematically and comprehensively investigated the effects of THP on dextran sulfate-induced UC mice and illustrated its specific mechanism of action. The colon and spleen in UC mice were restored after THP treatment. The levels of key markers, such as secretory immunoglobulin A, ß-defensin, and mucin-2 were increased, collagen deposition and epithelial cell apoptosis were decreased. Notably, THP administration led to increased levels of Ki67 and tight junction proteins in colon tissue and reduced colon tissue permeability. THP contributed to the restored balance of intestinal flora. Furthermore, THP downregulated the expressions of the proinflammatory cytokines interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-17 and promoted those of the regulatory factors forkhead box protein P3. It also exerted anti-inflammatory effects by promoting suppressor of cytokine signaling (SOCS1) expression and inhibiting the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. Our results demonstrated that THP had an efficacy comparable to that of JAK inhibitor in treating UC. In addition, THP might play a role in UC therapy through modulation of the SOCS1/JAK2/STAT3 signaling pathway and remodeling of the intestinal mucosal barrier.


Assuntos
Colite Ulcerativa , Função da Barreira Intestinal , Mucosa Intestinal , Polissacarídeos , Transdução de Sinais , Vitaceae , Animais , Masculino , Camundongos , Anti-Inflamatórios/farmacologia , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colo/efeitos dos fármacos , Colo/patologia , Citocinas/metabolismo , Sulfato de Dextrana , Modelos Animais de Doenças , Função da Barreira Intestinal/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Janus Quinase 2/metabolismo , Camundongos Endogâmicos C57BL , Polissacarídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Proteína 1 Supressora da Sinalização de Citocina/metabolismo , Proteína 1 Supressora da Sinalização de Citocina/genética , Vitaceae/química
3.
Biomacromolecules ; 25(6): 3345-3359, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38700942

RESUMO

The management of diabetic ulcers poses a significant challenge worldwide, and persistent hyperglycemia makes patients susceptible to bacterial infections. Unfortunately, the overuse of antibiotics may lead to drug resistance and prolonged infections, contributing to chronic inflammation and hindering the healing process. To address these issues, a photothermal therapy technique was incorporated in the preparation of wound dressings. This innovative solution involved the formulation of a self-healing and injectable hydrogel matrix based on the Schiff base structure formed between the oxidized Bletilla striata polysaccharide (BSP) and hydroxypropyltrimethylammonium chloride chitosan. Furthermore, the introduction of CuO nanoparticles encapsulated in polydopamine imparted excellent photothermal properties to the hydrogel, which promoted the release of berberine (BER) loaded on the nanoparticles and boosted the antibacterial performance. In addition to providing a reliable physical protection to the wound, the developed hydrogel, which integrated the herbal components of BSP and BER, effectively accelerated wound closure via microenvironment regulation, including alleviated inflammatory reaction, stimulated re-epithelialization, and reduced oxidative stress based on the promising results from cell and animal experiments. These impressive outcomes highlighted their clinical potential in safeguarding the wound against bacterial intrusion and managing diabetic ulcers.


Assuntos
Quitosana , Hidrogéis , Polissacarídeos , Cicatrização , Quitosana/química , Quitosana/análogos & derivados , Quitosana/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Hidrogéis/química , Hidrogéis/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Terapia Fototérmica/métodos , Camundongos , Humanos , Berberina/farmacologia , Berberina/química , Ratos , Diabetes Mellitus Experimental/tratamento farmacológico , Cobre/química , Cobre/farmacologia , Masculino , Polímeros/química , Polímeros/farmacologia , Indóis/química , Indóis/farmacologia , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia , Nanopartículas/química , Staphylococcus aureus/efeitos dos fármacos , Nanopartículas Metálicas/química
4.
Carbohydr Polym ; 333: 121922, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38494202

RESUMO

A novel acidic glucuronogalactomannan (STHP-5) was isolated from the aboveground part of Tetrastigma hemsleyanum Diels et Gilg with a molecular weight of 3.225 × 105 kDa. Analysis of chain conformation showed STHP-5 was approximately a random coil chain. STHP-5 was composed mainly of galactose, mannose, and glucuronic acid. Linkages of glycosides were measured via methylation analysis and verified by NMR. In vitro, STHP-5 induced the production of nitric oxide (NO) and secretion of IL-6, MCP-1, and TNF-α in RAW264.7 cells, indicating STHP-5 had stimulatory activity on macrophages. STHP-5 was proven to function as a TLR4 agonist by inducing the secretion of secreted embryonic alkaline phosphatase (SEAP) in HEK-Blue™-hTLR4 cells. The TLR4 activation capacity was quantitatively measured via EC50, and it showed purified polysaccharides had stronger effects (lower EC50) on activating TLR4 compared with crude polysaccharides. In conclusion, our findings suggest STHP-5 may be a novel immunomodulator.


Assuntos
Receptor 4 Toll-Like , Vitaceae , Animais , Camundongos , Vitaceae/química , Polissacarídeos/química , Macrófagos , Células RAW 264.7
5.
Int J Biol Macromol ; 265(Pt 2): 131015, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38521298

RESUMO

The anti-inflammatory activity of polysaccharides derived from Melastoma dodecandrum Lour. was evaluated in pyretic mice and HEK-Blue™ hTLR4 cells. The testing led to the identification of MDP2-1, which was then investigated for its structural characteristics and anti-inflammatory effects. Results showed that MDP2-1 had a molecular weight of 29.234 kDa and primarily consisted of galactose, arabinose, rhamnose, glucose, glucuronic acid, and galacturonic acid. Its main backbone was composed of →4)-α-D-GalpA-(1→, →2)-α-L-Rhap-(1→, →3,4)-α-D-GalpA-(1→, →2,4)-α-D-GlcpA-(1→, and its side chains were connected by →4)-α-D-Galp-(1→, α-D-Galp-(1→, →4)-ß-D-Glcp-(1→, and α-L-Araf-(1→. In vivo experiments on mice demonstrated that MDP2-1 attenuated LPS-induced acute lung injury, and in vitro experiments on RAW264.7 cells showed that MDP2-1 reduced the levels of inflammatory mediators and mitigated LPS-induced inflammatory damage by inhibiting the activation of the TLR4 downstream NF-κB/MAPK pathway. These findings suggest that MDP2-1 is a novel anti-inflammatory agent for therapeutic interventions.


Assuntos
Lipopolissacarídeos , Polissacarídeos , Camundongos , Animais , Polissacarídeos/farmacologia , Polissacarídeos/química , Galactose , Glucose , Anti-Inflamatórios/farmacologia
6.
Cell Host Microbe ; 32(4): 588-605.e9, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38531364

RESUMO

Many powerful methods have been employed to elucidate the global transcriptomic, proteomic, or metabolic responses to pathogen-infected host cells. However, the host glycome responses to bacterial infection remain largely unexplored, and hence, our understanding of the molecular mechanisms by which bacterial pathogens manipulate the host glycome to favor infection remains incomplete. Here, we address this gap by performing a systematic analysis of the host glycome during infection by the bacterial pathogen Brucella spp. that cause brucellosis. We discover, surprisingly, that a Brucella effector protein (EP) Rhg1 induces global reprogramming of the host cell N-glycome by interacting with components of the oligosaccharide transferase complex that controls N-linked protein glycosylation, and Rhg1 regulates Brucella replication and tissue colonization in a mouse model of brucellosis, demonstrating that Brucella exploits the EP Rhg1 to reprogram the host N-glycome and promote bacterial intracellular parasitism, thereby providing a paradigm for bacterial control of host cell infection.


Assuntos
Brucella , Brucelose , Animais , Camundongos , Brucella/fisiologia , Proteômica , Brucelose/metabolismo , Retículo Endoplasmático/metabolismo
7.
J Ethnopharmacol ; 319(Pt 3): 117361, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38380574

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Bletilla striata polysaccharides (BSP) extracted from the B. striata tuber, have been demonstrated to possess anti-inflammatory properties. However, their potential protective effect against ARDS and their role in regulating cell pyroptosis remained unexplored. AIM OF THE STUDY: The aim of this study was to investigate the therapeutic effect of BSP in the alleviation of lipopolysaccharide (LPS)-induced ARDS, and to explore its mechanism of action. METHODS: The effect of BSP was assessed by LPS injection into the intraperitoneal cavity in vivo; pathological changes of ARDS mice were gauged by immunohistochemical, hematoxylin and eosin staining, and immunofluorescence assays. MH-S cells were used to model the pyroptosis in vitro. Finally, the pyroptosis of alveolar macrophage was detected by western blots, qPCR, and flow cytometry for NLRP3/caspase1/GSDMD and HMGB1/TLR4 pathway-associated proteins and mRNA. RESULTS: BSP could significantly increase the weight and survival rate of mice with ARDS, alleviate the cytokine storm in the lungs, and reduce lung damage in vivo. BSP inhibited the inflammation caused by LPS/Nigericin significantly in vitro. Compared with the control group, there was a remarkable surge in the incidence of pyroptosis observed in ARDS lung tissue and alveolar macrophages, whereas BSP significantly diminished the pyroptosis ratio. Besides, BSP reduced NLRP3/caspase1/GSDMD and HMGB1/TLR4 levels in ARDS lung tissue and MH-S cells. CONCLUSIONS: These findings proved that BSP could improve LPS-induced ARDS via inhibiting pyroptosis, and this effect was mediated by NLRP3/caspase1/GSDMD and HMGB1/TLR4, suggesting a therapeutic potential of BSP as an anti-inflammatory agent for ARDS treatment.


Assuntos
Proteína HMGB1 , Síndrome do Desconforto Respiratório , Animais , Camundongos , Macrófagos Alveolares , Lipopolissacarídeos/toxicidade , Proteína 3 que Contém Domínio de Pirina da Família NLR , Piroptose , Receptor 4 Toll-Like , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Pulmão
8.
IEEE Trans Pattern Anal Mach Intell ; 46(7): 4597-4611, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38271171

RESUMO

Helmholtz stereopsis (HS) exploits the reciprocity principle of light propagation (i.e., the Helmholtz reciprocity) for 3D reconstruction of surfaces with arbitrary reflectance. In this paper, we present the polarimetric Helmholtz stereopsis (polar-HS), which extends the classical HS by considering the polarization state of light in the reciprocal paths. With the additional phase information from polarization, polar-HS requires only one reciprocal image pair. We derive the reciprocity relationship of Mueller matrix and formulate new reciprocity constraint that takes polarization state into account. We also utilize polarimetric constraints and extend them to the case of perspective projection. For the recovery of surface depths and normals, we incorporate reciprocity constraint with diffuse/specular polarimetric constraints in a unified optimization framework. For depth estimation, we further propose to utilize the consistency of diffuse angle of polarization. For normal estimation, we develop a normal refinement strategy based on degree of linear polarization. Using a hardware prototype, we show that our approach produces high-quality 3D reconstruction for different types of surfaces, ranging from diffuse to highly specular.

9.
Materials (Basel) ; 17(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38255547

RESUMO

The evaluation of the elastic modulus of recycled concrete is one of the focuses of civil engineering and structural engineering, which is not only related to the stability of building structures but also related to the resource utilization of concrete. Therefore, based on the IRSM method in mesoscale, a novel model for predicting the elastic modulus of recycled concrete is proposed which has the advantages of being low-cost and high-precision, amongst others, compared to theoretical and experimental methods. Then, the influence of coarse aggregate, contact surface, gelling material, and air bubbles on the elastic modulus of recycled concrete is studied. The IRSM model includes four processes: Identification, Reconstruction, Simulation, and Monte Carlo, which can accurately reconstruct the geometric characteristics of coarse aggregate, efficiently reconstruct the coarse aggregate accumulation model, and quickly analyze the elastic modulus of concrete, as well as fully consider the nonuniform characteristics of coarse aggregate distribution and shape. Compared with the experimental results, the error is less than 5%, which verifies the rationality of the IRSM method. The results of the parametric analysis show that the influence of each factor on the elastic modulus of concrete in descending order is elastic modulus of cement, elastic modulus of coarse aggregate, content of coarse aggregate, content of air voids, elastic modulus of contacting surface, and thickness of contacting surface, and the corresponding Pearson's Coefficients are 0.688, 0.427, 0.412, -0.269, 0.188, and -0.061, respectively, in which the content of air voids and thickness of contact surface have a negative effect on the elastic modulus of concrete. These influences mainly affect the deformation resistance (elastic modulus) of concrete through "force chain" adjustment, including the force transfer effect, number of paths, and integrity.

10.
Int J Mol Sci ; 24(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38003478

RESUMO

The healing process of a diabetic wound (DW) is often impeded by a series of interrelated factors, including severe infection, persistent inflammation, and excessive oxidative stress. Therefore, it is particularly crucial to develop a medical dressing that can address these issues simultaneously. To this end, different ratios of Bletilla striata polysaccharide (BSP) and berberine (BER) were physically blended with Carbomer 940 (CBM940) to develop a composite hydrogel as a medical dressing. The BSP/BER hydrogel was characterized using SEM, FTIR, rheological testing and other techniques. The anti-inflammatory, antioxidant, and antibacterial properties of the hydrogel were evaluated using cell and bacterial models in vitro. A DW model of ICR mice was established to evaluate the effect of the hydrogel on DW healing in vivo. The hydrogel exhibited excellent biocompatibility and remarkable antibacterial, anti-inflammatory, and antioxidant properties. In addition, animal experiments showed that the BSP/BER hydrogel significantly accelerated wound healing in DW mice. Among the different formulations, the LBSP/BER hydrogel (2% BSP, mBER:mBSP = 1:40) demonstrated the most remarkable efficacy. In conclusion, the BSP/BER hydrogel developed exhibited immense properties and great potential as a medical dressing for the repair of DW, addressing a crucial need in clinical practice.


Assuntos
Berberina , Diabetes Mellitus , Animais , Camundongos , Hidrogéis/farmacologia , Berberina/farmacologia , Berberina/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Camundongos Endogâmicos ICR , Cicatrização , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Bandagens , Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia
11.
J Biomater Appl ; 38(3): 424-437, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37599387

RESUMO

Diabetic wounds impose enormous distress and financial burden on patients, and finding effective dressings to manage wounds is critical. As a Chinese herbal medicine with a long history of Clinical application, Bletilla striata has significant medicinal effects in the therapy of various wounds. In this study, PLA and the pharmacodynamic substances of Bletilla striata were prepared into fibrous scaffolds by emulsion electrospinning technology for the management of diabetic wounds in mice. The results of scanning electron microscopy showed that the core-shell structure fibre was successfully obtained by emulsion electrospinning. The fibre membrane exhibited excellent water absorption capability and water vapor transmission rate, could inhibit the growth of Staphylococcus aureus and Pseudomonas aeruginosa, had good compatibility, and achieved excellent healing effect on diabetic wounds. Especially in the in vivo wound healing experiment, the wound healing rate of composite fibre membrane treatment reached 98.587 ± 2.149% in 16 days. This work demonstrated the good therapeutic effect of the developed fibrous membrane to diabetic wound, and this membrane could be potentially applied to chronic wound healing.


Assuntos
Diabetes Mellitus , Nanofibras , Animais , Camundongos , Emulsões , Nanofibras/uso terapêutico , Cicatrização , Microscopia Eletrônica de Varredura , Pseudomonas aeruginosa
12.
Cell Syst ; 14(7): 605-619.e7, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37473731

RESUMO

Spatial variation in cellular phenotypes underlies heterogeneity in immune recognition and response to therapy in cancer and many other diseases. Spatial transcriptomics holds the potential to quantify such variation, but existing analysis methods are limited by their focus on individual tasks such as spot deconvolution. We present BayesTME, an end-to-end Bayesian method for analyzing spatial transcriptomics data. BayesTME unifies several previously distinct analysis goals under a single, holistic generative model. This unified approach enables BayesTME to deconvolve spots into cell phenotypes without any need for paired single-cell RNA-seq. BayesTME then goes beyond spot deconvolution to uncover spatial expression patterns among coordinated subsets of genes within phenotypes, which we term spatial transcriptional programs. BayesTME achieves state-of-the-art performance across myriad benchmarks. On human and zebrafish melanoma tissues, BayesTME identifies spatial transcriptional programs that capture fundamental biological phenomena such as bilateral symmetry and tumor-associated fibroblast and macrophage reprogramming. BayesTME is open source.


Assuntos
Benchmarking , Peixe-Zebra , Humanos , Animais , Teorema de Bayes , Peixe-Zebra/genética , Perfilação da Expressão Gênica , Macrófagos
13.
Opt Lett ; 48(7): 1690-1693, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221742

RESUMO

An improved ellipse-fitting algorithm phase demodulation (EFAPD) technique is proposed to reduce the influence of light source intensity noise on a system. In the original EFAPD, the sum of the intensities of coherent light (ICLS) is an important part of the interference signal noise, which makes the demodulation results suffer. The improved EFAPD corrects the ICLS and fringe contrast quantity of the interference signal by an ellipse-fitting algorithm, and then calculates the ICLS based on the structure of pull-cone 3 × 3 coupler, so as to remove it in the algorithm. Experimental results show that the noise of the improved EFAPD system is significantly reduced compared with that of the original EFAPD, with a maximum reduction of 35.57 dB. The improved EFAPD makes up for the deficiency of the original EFAPD in suppressing light source intensity noise, and promotes the application and popularization of EFAPD.

14.
J Physiol ; 601(22): 5107-5128, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37078283

RESUMO

Long-term abuse of methamphetamine (MA) can cause lung toxicity. Intercellular communication between macrophages and alveolar epithelial cells (AECs) is critical for maintaining lung homeostasis. Microvesicles (MVs) are an important medium of intercellular communication. However, the mechanism of macrophage MVs (MMVs) in MA-induced chronic lung injury remains unclear. This study aimed to investigate if MA can augment the activity of MMVs and if circ_YTHDF2 is a key factor in MMV-mediated macrophage-AEC communication, and to explore the mechanism of MMV-derived circ_YTHDF2 in MA-induced chronic lung injury. MA elevated peak velocity of the pulmonary artery and pulmonary artery accelerate time, reduced the number of alveolar sacs, thickened the alveolar septum, and accelerated the release of MMVs and the uptake of MMVs by AECs. Circ_YTHDF2 was downregulated in lung and MMVs induced by MA. The immune factors in MMVs were increased by si-circ_YTHDF. Circ_YTHDF2 knockdown in MMVs induced inflammation and remodelling in the internalised AECs by MMVs, which was reversed by circ_YTHDF2 overexpression in MMVs. Circ_YTHDF2 bound specifically to and sponged miRNA-145-5p. Runt-related transcription factor 3 (RUNX3) was identified as potential target of miR-145-5p. RUNX3 targeted zinc finger E-box-binding homeobox 1 (ZEB1)-related inflammation and EMT of AECs. In vivo, circ_YTHDF2 overexpression-MMVs attenuated MA-induced lung inflammation and remodelling by the circ_YTHDF2-miRNA-145-5p-RUNX3 axis. Therefore, MA abuse can induce pulmonary dysfunction and alveolus injury. The immunoactivity of MMVs is regulated by circ_YTHDF2. Circ_YTHDF2 in MMVs is the key to communication between macrophages and AECs. Circ_YTHDF2 sponges miR-145-5p targeting RUNX3 to participate in ZEB1-related inflammation and remodelling of AECs. MMV-derived circ_YTHDF2 would be an important therapeutic target for MA-induced chronic lung injury. KEY POINTS: Methamphetamine (MA) abuse induces pulmonary dysfunction and alveoli injury. The immunoactivity of macrophage microvesicles (MMVs) is regulated by circ_YTHDF2. Circ_YTHDF2 in MMVs is the key to MMV-mediated intercellular communication between macrophages and alveolar epithelial cells. Circ_YTHDF2 sponges miR-145-5p targeting runt-related transcription factor 3 (RUNX3) to participate in zinc finger E-box-binding homeobox 1 (ZEB1)-related inflammation and remodelling. MMV-derived circ_YTHDF2 would be an important therapeutic target for MA-induced chronic lung injury.


Assuntos
Lesão Pulmonar , Metanfetamina , MicroRNAs , Humanos , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/genética , Metanfetamina/toxicidade , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Fator 3 de Transcrição/metabolismo , Inflamação/metabolismo , Macrófagos , MicroRNAs/genética , MicroRNAs/metabolismo , Proliferação de Células , Apoptose , Proteínas de Ligação a RNA
15.
Int J Biol Macromol ; 241: 124419, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37080409

RESUMO

The intestinal mucosal barrier is one of the important barriers to prevent harmful substances and pathogens from entering the body environment and to maintain intestinal homeostasis. This study investigated the reparative effect and possible mechanism of Tetrastigma hemsleyanum polysaccharides (THP) on ceftriaxone-induced intestinal mucosal damage. Our results suggested that THP repaired the mechanical barrier damage of intestinal mucosa by enhancing the expression of intestinal tight junction proteins, reducing intestinal mucosal permeability and improving the pathological state of intestinal epithelial cells. Intestinal immune and chemical barrier was further restored by THP via the increment of the body's cytokine levels, intestinal SIgA levels, intestinal goblet cell number, intestinal mucin-2 levels, and short-chain fatty acid levels. In addition, THP increased the abundance of probiotic bacteria (such as Lactobacillus), reduced the abundance of harmful bacteria (such as Enterococcus) to repair the intestinal biological barrier, restored intestinal mucosal barrier function, and maintains intestinal homeostasis. The possible mechanisms were related to sphingolipid metabolism, linoleic acid metabolism, and D-glutamine and D-glutamate metabolism. Our results demonstrated the potential therapeutic effect of THP against intestinal flora disorders and intestinal barrier function impairment caused by antibiotics.


Assuntos
Antibacterianos , Microbiota , Animais , Camundongos , Antibacterianos/efeitos adversos , Antibacterianos/metabolismo , Mucosa Intestinal/metabolismo , Polissacarídeos/química , Metaboloma
16.
Zhen Ci Yan Jiu ; 48(2): 153-7, 2023 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-36858411

RESUMO

Acupuncture therapy has been widely used in clinical treatment of allergic rhinitis (AR), and can induce a positive therapeutic effect through multi-targets and multi-aspects. In recent 10 years, the research on the mechanisms of acupuncture in treating AR mainly focused on humoral immunity, cellular immunity, cell apoptosis, inflammatory mediators and factors, neuropeptides, etc. By regulating the level of immunoglobulin in the blood, acupuncture intervention can restore the relative balance of cellular immune response, reduce the accumulation of eosinophils and promote apoptosis, down-regulate the expression of related inflammatory mediators and factors, regulate the excitability of related nerves, modulate the release of neuropeptides and other ways to diminish the inflammatory reaction of nasal mucosa, and enhance the repair and protection of nasal mucosa, relieve the nasal symptoms at last. On the basis of the existing studies, the follow-up research should make use of the advantages of acupuncture intervention, refine the treatment process, and deeply explore the feasibility of acupuncture treatment of AR, further promote the combination of mechanism study and clinical practice, provide references for clinical application. Moreover, some shortcomings exist, for example, the unknown correlation between the therapeutic effect and duration of treatment, the unknown correlation between the effect of acupuncture and various targets, and disconnection between experimental research achievements and clinical application, etc.


Assuntos
Terapia por Acupuntura , Rinite Alérgica , Humanos , Mucosa Nasal , Inflamação , Apoptose
17.
Materials (Basel) ; 16(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36770329

RESUMO

Asphalt concrete has been used as a material for dam core walls because of its impermeability, durability and reliability. Firstly, asphalt is a temperature-sensitive material, and many of its characteristics are related to temperature. Secondly, because of the increasing construction height of the dam, the pressure on the asphalt concrete core wall is also great. Finally, for the purpose of resource utilization, it is necessary to verify whether the reclaimed asphalt concrete can be used in dam construction. Therefore, it is necessary to study the stress and deformation characteristics of recycled asphalt concrete under different temperatures and confining pressures. In this study, three groups of triaxial tests of reclaimed asphalt concrete were carried out for the first time in a new temperature-controlled room. Duncan Zhang's E-v model was used to fit the test results. The results show that the stress-strain curves of reclaimed asphalt concrete show softening characteristics at low temperatures and low confining pressure. It evolves to a hardening type with the increase in temperature and confining pressure. The bulk curve is first contracts but is followed by dilatancy. The dilatancy characteristics become more obvious at low temperatures and low confining pressure. With the increase in temperature and confining pressure, the dilatancy characteristics will weaken. Duncan Zhang's E-v model has a good fitting effect on the stress-strain relationship but a poor fitting effect on the volumetric curve. The research of this paper can better combine the utilization of waste resources with engineering and achieve the aim of resource-saving and waste utilization under the premise of ensuring the safety of the engineering.

18.
IEEE Trans Neural Netw Learn Syst ; 34(8): 4273-4285, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34591772

RESUMO

Organizing the implicit topology of a document as a graph, and further performing feature extraction via the graph convolutional network (GCN), has proven effective in document analysis. However, existing document graphs are often restricted to expressing single-level relations, which are predefined and independent of downstream learning. A set of learnable hierarchical graphs are built to explore multilevel sentence relations, assisted by a hierarchical probabilistic topic model. Based on these graphs, multiple parallel GCNs are used to extract multilevel semantic features, which are aggregated by an attention mechanism for different document-comprehension tasks. Equipped with variational inference, the graph construction and GCN are learned jointly, allowing the graphs to evolve dynamically to better match the downstream task. The effectiveness and efficiency of the proposed multilevel sentence relation graph convolutional network (MuserGCN) is demonstrated via experiments on document classification, abstractive summarization, and matching.

19.
IEEE Trans Pattern Anal Mach Intell ; 45(4): 4586-4604, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35853051

RESUMO

For document analysis, existing methods often resort to the document representation that either discards the word order information or projects each word into a low-dimensional dense embedding vector. However, confined by the data's sparsity and high-dimensionality, limited effort has been made to explore the semantic structures underlying the document representation that formulates each document as a sequence of one-hot vectors, especially in the probabilistic modeling literature. To construct a probabilistic generative model for this type of document representation, we first develop convolutional Poisson factor analysis (CPFA) that not only utilizes the sparse property of data but also enables model parallelism. Through interleaving probabilistic Dirichlet-gamma pooling layers with learnable parameters, we extend the shallow CPFA into a generative text convolutional neural network (GTCNN), which captures richer semantic information with multiple probabilistic convolutional layers and can be coupled with existing deep topic models to alleviate their loss of word order. For efficient and scalable model inference, we not only develop both a parallel upward-downward Gibbs sampler and SG-MCMC based algorithm for training GTCNN, but also construct a hierarchical Weibull convolutional inference network for fast out-of-sample prediction. Experimental results on document representation learning tasks demonstrate the effectiveness of the proposed methods.

20.
Biomed Pharmacother ; 155: 113755, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36182735

RESUMO

Tetrastigma Hemsleyanum Diels et Gilg (Sanyeqing, SYQ), a traditional herb native to China, has been widely used in the treatment of inflammatory diseases, febrile convulsions and dysentery. Previous studies have demonstrated the hypoglycemic, anti-inflammatory and anti-pyretic effects of polysaccharides from SYQ (SYQP). However, the role of SYQP in acute lung injury (ALI) remained unknown. Our present study aimed to explore the protective effects of SYQP in ALI and explained its underlying mechanism. In vivo, Balb/c mice were intragastrically administered with SYQP and dexamethasone (DXMS) for 14 days which were intratracheally instilled (IT) with LPS at the last day. In vitro, A549 cells were pretreated with SYQP, DXMS or TAK-242, following by LPS stimulation for 24 h. The histopathological results showed that SYQP remarkably alleviated pulmonary macrophage infiltration and myeloperoxidase (MPO) levels. Additionally, SYQP evidently suppressed wet/dry (W/D) ratio of lung and white blood cells (WBC) in bronchoalveolar lavage fluid (BALF). Moreover, SYQP markedly reduced TNF-α, IL-6, IL-1ß and COX-2 levels both in vivo and in vitro. Meanwhile, SYQP significantly attenuated oxidative stress through upregulating the levels of SOD and GSH-Px and downregulating the expressions of MDA and LDH in vivo, which was confirmed by in vitro results that SYQP could increase SOD activity and decrease MDA and NO contents. Importantly, a decline in protein expressions of TLR4, COX-2, NF-κB p50, phospho-NF-κB p65 and phospho-IκB-α was detected in vivo and in vitro. Taken together, our results demonstrated that SYQP ameliorated LPS-induced ALI by alleviating inflammation and oxidative stress via attenuating TLR4/COX-2/NF-κB signaling pathway.


Assuntos
Lesão Pulmonar Aguda , NF-kappa B , Camundongos , Animais , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo , Lipopolissacarídeos/farmacologia , Peroxidase/metabolismo , Ciclo-Oxigenase 2/metabolismo , Inibidor de NF-kappaB alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Interleucina-6/farmacologia , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/metabolismo , Transdução de Sinais , Anti-Inflamatórios/efeitos adversos , Superóxido Dismutase/metabolismo , Dexametasona/farmacologia , Hipoglicemiantes/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...