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1.
Biomed Pharmacother ; 165: 115276, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37542852

RESUMO

Short-chain fatty acids (SCFAs) derived from the fermentation of carbohydrates by gut microbiota play a crucial role in regulating host physiology. Among them, acetate, propionate, and butyrate are key players in various biological processes. Recent research has revealed their significant functions in immune and inflammatory responses. For instance, butyrate reduces the development of interferon-gamma (IFN-γ) generating cells while promoting the development of regulatory T (Treg) cells. Propionate inhibits the initiation of a Th2 immune response by dendritic cells (DCs). Notably, SCFAs have an inhibitory impact on the polarization of M2 macrophages, emphasizing their immunomodulatory properties and potential for therapeutics. In animal models of asthma, both butyrate and propionate suppress the M2 polarization pathway, thus reducing allergic airway inflammation. Moreover, dysbiosis of gut microbiota leading to altered SCFA production has been implicated in prostate cancer progression. SCFAs trigger autophagy in cancer cells and promote M2 polarization in macrophages, accelerating tumor advancement. Manipulating microbiota- producing SCFAs holds promise for cancer treatment. Additionally, SCFAs enhance the expression of hypoxia-inducible factor 1 (HIF-1) by blocking histone deacetylase, resulting in increased production of antibacterial effectors and improved macrophage-mediated elimination of microorganisms. This highlights the antimicrobial potential of SCFAs and their role in host defense mechanisms. This comprehensive review provides an in-depth analysis of the latest research on the functional aspects and underlying mechanisms of SCFAs in relation to macrophage activities in a wide range of diseases, including infectious diseases and cancers. By elucidating the intricate interplay between SCFAs and macrophage functions, this review aims to contribute to the understanding of their therapeutic potential and pave the way for future interventions targeting SCFAs in disease management.


Assuntos
Microbioma Gastrointestinal , Propionatos , Masculino , Animais , Propionatos/uso terapêutico , Ácidos Graxos Voláteis/metabolismo , Butiratos/farmacologia , Butiratos/uso terapêutico , Inflamação/tratamento farmacológico , Microbioma Gastrointestinal/fisiologia , Macrófagos/metabolismo
2.
Nucleic Acids Res ; 51(D1): D1263-D1275, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36243960

RESUMO

Widespread drug resistance has become the key issue in global healthcare. Extensive efforts have been made to reveal not only diverse diseases experiencing drug resistance, but also the six distinct types of molecular mechanisms underlying this resistance. A database that describes a comprehensive list of diseases with drug resistance (not just cancers/infections) and all types of resistance mechanisms is now urgently needed. However, no such database has been available to date. In this study, a comprehensive database describing drug resistance information named 'DRESIS' was therefore developed. It was introduced to (i) systematically provide, for the first time, all existing types of molecular mechanisms underlying drug resistance, (ii) extensively cover the widest range of diseases among all existing databases and (iii) explicitly describe the clinically/experimentally verified resistance data for the largest number of drugs. Since drug resistance has become an ever-increasing clinical issue, DRESIS is expected to have great implications for future new drug discovery and clinical treatment optimization. It is now publicly accessible without any login requirement at: https://idrblab.org/dresis/.


Assuntos
Descoberta de Drogas , Bases de Dados Factuais , Resistência a Medicamentos
3.
J Neuroinflammation ; 19(1): 244, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36195881

RESUMO

BACKGROUND: Neuropathic pain is still a challenge for clinical treatment as a result of the comprehensive pathogenesis. Although emerging evidence demonstrates the pivotal role of glial cells in regulating neuropathic pain, the role of Schwann cells and their underlying mechanisms still need to be uncovered. Pannexin 1 (Panx 1), an important membrane channel for the release of ATP and inflammatory cytokines, as well as its activation in central glial cells, contributes to pain development. Here, we hypothesized that Schwann cell Panx 1 participates in the regulation of neuroinflammation and contributes to neuropathic pain. METHODS: A mouse model of chronic constriction injury (CCI) in CD1 adult mice or P0-Cre transgenic mice, and in vitro cultured Schwann cells were used. Intrasciatic injection with Panx 1 blockers or the desired virus was used to knock down the expression of Panx 1. Mechanical and thermal sensitivity was assessed using Von Frey and a hot plate assay. The expression of Panx 1 was measured using qPCR, western blotting, and immunofluorescence. The production of cytokines was monitored through qPCR and enzyme-linked immunosorbent assay (ELISA). Panx1 channel activity was detected by ethidium bromide (EB) uptake. RESULTS: CCI induced persistent neuroinflammatory responses and upregulation of Panx 1 in Schwann cells. Intrasciatic injection of Panx 1 blockers, carbenoxolone (CBX), probenecid, and Panx 1 mimetic peptide (10Panx) effectively reduced mechanical and heat hyperalgesia. Probenecid treatment of CCI-induced mice significantly reduced Panx 1 expression in Schwann cells, but not in dorsal root ganglion (DRG). In addition, Panx 1 knockdown in Schwann cells with Panx 1 shRNA-AAV in P0-Cre mice significantly reduced CCI-induced neuropathic pain. To determine whether Schwann cell Panx 1 participates in the regulation of neuroinflammation and contributes to neuropathic pain, we evaluated its effect in LPS-treated Schwann cells. We found that inhibition of Panx 1 via CBX and Panx 1-siRNA effectively attenuated the production of selective cytokines, as well as its mechanism of action being dependent on both Panx 1 channel activity and its expression. CONCLUSION: In this study, we found that CCI-related neuroinflammation correlates with Panx 1 activation in Schwann cells, indicating that inhibition of Panx 1 channels in Schwann cells reduces neuropathic pain through the suppression of neuroinflammatory responses.


Assuntos
Carbenoxolona , Neuralgia , Trifosfato de Adenosina/farmacologia , Animais , Carbenoxolona/farmacologia , Carbenoxolona/uso terapêutico , Conexinas/genética , Conexinas/metabolismo , Citocinas/metabolismo , Etídio/metabolismo , Etídio/farmacologia , Etídio/uso terapêutico , Hiperalgesia/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Neuralgia/metabolismo , Probenecid/metabolismo , Probenecid/farmacologia , Probenecid/uso terapêutico , RNA Interferente Pequeno/metabolismo , Células de Schwann
4.
Front Pharmacol ; 13: 1019312, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36313354

RESUMO

The reprogramming of cellular metabolism is frequently linked to tumorigenesis. Glucose, fatty acids, and amino acids are the specific substrates involved in how an organism maintains metabolic equilibrium. The HADH gene codes for the short-chain L-3-hydroxyacyl-CoA dehydrogenase (HADH), a crucial enzyme in fatty acid oxidation that catalyzes the third phase of fatty acid oxidation in mitochondria. Increasing data suggest that HADH is differentially expressed in various types of malignancies and is linked to cancer development and progression. The significance of HADH expression in tumors and its potential mechanisms of action in the onset and progression of certain cancers are summarized in this article. The possible roles of HADH as a target and/or biomarker for the detection and treatment of various malignancies is also described here.

5.
Front Oncol ; 12: 943703, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35928866

RESUMO

Purpose: The aim of this study is to evaluate the efficacy and toxicity of image-guided high-dose rate (HDR) interstitial brachytherapy (ISBT) for the reirradiation of cervical cancer within a previously irradiated area. Methods and materials: Twenty-three consecutive patients with cervical cancer were reirradiated with curative intent using brachytherapy (BT) with or without external beam irradiation. The median biologically equivalent dose in 2-Gy fractions (EQD2) for reirradiation was 64.0 Gy (range: 31.3-95.1 Gy), and the median cumulative EQD2 (for primary treatment and reirradiation) was 152.4 Gy (range: 97.8-200.9 Gy). The average clinical target volume was 82.9 cm3 (range: 26.9-208.3 cm3), and the median treatment-free interval (TFI) was 13 months (range: 3-93 months). Results: The median follow-up time was 19 months (range: 2-59 months). The complete response rate after reirradiation was 56.5%. The 1-, 2- 3-, and 4-year post-relapse survival (PRS) rates were 65.2%, 43.5%, 33.8%, and 27.1%, respectively. The median reirradiation EQD2 D2cc of rectum and bladder was 39.5 Gy (range = 14.6-96.2 Gy) and 52.1 Gy (range = 29.1-114.2 Gy). The median cumulative EQD2 D2cc of rectum and bladder was 115.0 Gy (range = 84.4-189.3 Gy) and 130.5 Gy (range = 95.5-173.5 Gy). During follow-up, nine (39.1%) patients had experienced grade 3 or 4 late toxicities. Grade ≥3 rectal toxicity occurred in three patients (13.0%). Grade ≥3 urinary toxicity occurred in five patients (21.7%). One patient (4.3%) had both grade ≥3 urinary and rectal toxicity. Tumor volume, TFI, tumor invasion organ number, and local control were significant prognostic factors adversely affecting OS. Conclusions: For recurrent cervical cancer after radiotherapy, reirradiation of HDR-ISBT is feasible, even if the local tumor invasion is large, with a good chance of survival and acceptable side effects.

6.
J Opt Soc Am A Opt Image Sci Vis ; 39(2): 227-232, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35200957

RESUMO

Achieving extremely high sensitivity is an important indicator in the development of novel and stable gas concentration sensors. In this paper, we present a gas concentration sensor with parity-time symmetry for high sensitivity at low concentrations. The proposed sensor can detect toxic gases, such as benzene, bromine, and acetone, by probing the faint changing of the permittivity. Furthermore, the level of the sensitivity can be adjusted by the resistance segment, which is realized by various metallic formations. Our proposed structure provides a novel idea for the development of future gas concentration sensors, showing an exciting prospect for gas sensing technologies.

7.
Front Immunol ; 12: 764749, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34925334

RESUMO

Several C2 domain-containing proteins play key roles in tumorigenesis, signal transduction, and mediating protein-protein interactions. Tandem C2 domains nuclear protein (TC2N) is a tandem C2 domain-containing protein that is differentially expressed in several types of cancers and is closely associated with tumorigenesis and tumor progression. Notably, TC2N has been identified as an oncogene in lung and gastric cancer but as a tumor suppressor gene in breast cancer. Recently, a large number of tumor-associated antigens (TAAs), such as heat shock proteins, alpha-fetoprotein, and carcinoembryonic antigen, have been identified in a variety of malignant tumors. Differences in the expression levels of TAAs between cancer cells and normal cells have led to these antigens being investigated as diagnostic and prognostic biomarkers and as novel targets in cancer treatment. In this review, we summarize the clinical characteristics of TC2N-positive cancers and potential mechanisms of action of TC2N in the occurrence and development of specific cancers. This article provides an exploration of TC2N as a potential target for the diagnosis and treatment of different types of cancers.


Assuntos
Antígenos de Neoplasias/genética , Genes Supressores de Tumor , Neoplasias/genética , Antígenos de Neoplasias/imunologia , Humanos , Neoplasias/imunologia
8.
Brief Bioinform ; 22(3)2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32510566

RESUMO

More than 48 kinase inhibitors (KIs) have been approved by Food and Drug Administration. However, drug-resistance (DR) eventually occurs, and secondary mutations have been found in the previously targeted primary-mutated cancer cells. Cancer and drug research communities recognize the importance of the kinase domain (KD) mutations for kinasopathies. So far, a systematic investigation of kinase mutations on DR hotspots has not been done yet. In this study, we systematically investigated four types of representative mutation hotspots (gatekeeper, G-loop, αC-helix and A-loop) associated with DR in 538 human protein kinases using large-scale cancer data sets (TCGA, ICGC, COSMIC and GDSC). Our results revealed 358 kinases harboring 3318 mutations that covered 702 drug resistance hotspot residues. Among them, 197 kinases had multiple genetic variants on each residue. We further computationally assessed and validated the epidermal growth factor receptor mutations on protein structure and drug-binding efficacy. This is the first study to provide a landscape view of DR-associated mutation hotspots in kinase's secondary structures, and its knowledge will help the development of effective next-generation KIs for better precision medicine.


Assuntos
Bases de Dados de Proteínas , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Neoplasias/genética , Neoplasias/genética , Receptores ErbB/genética , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Estrutura Secundária de Proteína
9.
Therap Adv Gastroenterol ; 12: 1756284819880733, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31662792

RESUMO

OBJECTIVES: Transcribed ultraconserved region (T-UCR) uc.261 is reported to participate in intestinal mucosa barrier damage in Crohn's disease (CD). The aim of this study was to determine the association with disease activity and intestinal permeability. METHODS: Uc.261 level in colon mucosa and Harvey-Bradshaw Index (HBI) were evaluated in 20 active CD patients. Uc.261 expression and transepithelial electrical resistance (TEER) were determined in Caco2 and T84 cells treated with tumor necrosis factor alpha (TNF-α), respectively. Body weight, disease activity index (DAI), colon length, histological index (HI), intestinal permeability to FITC-dextran, uc.261, and tight junction proteins (TJPs) levels were evaluated in BALB/C mice treated with saline enema, trinitrobenzene sulfonic acid (TNBS)/ethanol enema, and anti-TNF-α monoclonal antibody injection, respectively. RESULTS: Uc.261 expression was overexpressed in CD patients, TNF-α treated cells, and colitis mice. Uc.261 expression was positively correlated with HBI (r = 0.582, p = 0.007) in CD patients, and positively correlated with TNF-α concentration and negatively correlated TEER in Caco2 and T84 cells (all p < 0.05). Furthermore, uc.261 was positively correlated with DAI (r = 0.824, p = 0.008), HI (r = 0.672, p = 0.021), and intestinal permeability (r = 0.636, p = 0.012), while negatively correlated with body weight (r = -0.574, p = 0.035), colon length (r = -0.866, p = 0.017), and TJP expression (all p < 0.05) in colitis mice. CONCLUSIONS: Uc.261 expression was closely correlated with disease activity and intestinal permeability in CD. Anti-TNF-α treatment may play its role through suppressing uc.261 expression in colitis mice.

10.
Opt Express ; 27(3): 1991-2000, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30732244

RESUMO

A carbon dioxide (CO2) gas sensor based on a polyhexamethylene biguanide (PHMB)-coated whispering gallery mode (WGM) microbubble resonator is proposed and verified experimentally in this work. Microbubbles were fabricated using two reverse arc discharges focused on microcapillaries. The inner wall of the microbubble was coated with a layer of PHMB using a filling and sintering process. A significant WGM resonance was observed by coupling with a tapered fiber. The experimental results show that as the concentration of carbon dioxide increases, a blue shift appears in the spectrum. Addition, a high sensitivity (0.46 pm /ppm) and a good linear relationship were obtained in the measurement range of 200-700 ppm with a detection limit of 50 ppm. The sensor features include high sensitivity, simple structure, easy manufacture, and low cost.

11.
Curr Stem Cell Res Ther ; 13(8): 658-664, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30095059

RESUMO

There is increasing evidence reporting that as a common phenomenon in MetS relative diseases, insulin resistance (IR) is regarded as an independent etiological factor and a warning indicator of MetS occurrence. Therefore, for the special group (overweight or obesity), clinical regular monitoring of IR is an important basis for the prevention and early intervention of MetS relative diseases. This surveys reveals that human umbilical cord mesenchymal stem cells (HUC-MSCs)possess a kind of potential: it may become a possible theraphy for IR in type 2 diabetes mellitus (T2DM) and related diseases. Specific emphasis is focused on evaluating the improvement IR function of HUC-MSCs under the background of development in vitro and in vivo. Next, the action mechanisms of HUC-MSCs is discussed, and some of their advantages and disadvantages in the course of clinic application are presented. The final section highlights the application of HUC-MSCs in T2DM and relative diseases at this stage. Up to now, although many questions remain unresolved, we still consider that HUC-MSCs is one of the best therapy ameliorating IR in the future.


Assuntos
Resistência à Insulina , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Cordão Umbilical/citologia , Diabetes Mellitus/terapia , Humanos , Pesquisa Translacional Biomédica
12.
BMC Bioinformatics ; 19(1): 19, 2018 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-29361928

RESUMO

BACKGROUND: Many common clustering algorithms require a two-step process that limits their efficiency. The algorithms need to be performed repetitively and need to be implemented together with a model selection criterion. These two steps are needed in order to determine both the number of clusters present in the data and the corresponding cluster memberships. As biomedical datasets increase in size and prevalence, there is a growing need for new methods that are more convenient to implement and are more computationally efficient. In addition, it is often essential to obtain clusters of sufficient sample size to make the clustering result meaningful and interpretable for subsequent analysis. RESULTS: We introduce Shrinkage Clustering, a novel clustering algorithm based on matrix factorization that simultaneously finds the optimal number of clusters while partitioning the data. We report its performances across multiple simulated and actual datasets, and demonstrate its strength in accuracy and speed applied to subtyping cancer and brain tissues. In addition, the algorithm offers a straightforward solution to clustering with cluster size constraints. CONCLUSIONS: Given its ease of implementation, computing efficiency and extensible structure, Shrinkage Clustering can be applied broadly to solve biomedical clustering tasks especially when dealing with large datasets.


Assuntos
Algoritmos , Encéfalo/metabolismo , Neoplasias da Mama/diagnóstico , Análise por Conglomerados , Bases de Dados Factuais , Feminino , Regulação da Expressão Gênica , Humanos , Neoplasias/classificação , Neoplasias/genética , Neoplasias/patologia
13.
Talanta ; 150: 135-41, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26838391

RESUMO

In this paper, we present a compact handheld laser-induced fluorescence (LIF) detector based on a 450 nm laser diode and quasi-confocal optical configuration with a total size of 9.1 × 6.2 × 4.1 cm(3). Since there are few reports on the use of 450 nm laser diode in LIF detection, especially in miniaturized LIF detector, we systematically investigated various optical arrangements suitable for the requirements of 450 nm laser diode and system miniaturization, including focusing lens, filter combination, and pinhole, as well as Raman effect of water at 450 nm excitation wavelength. As the result, the handheld LIF detector integrates the light source (450 nm laser diode), optical circuit module (including a 450 nm band-pass filter, a dichroic mirror, a collimating lens, a 525 nm band-pass filter, and a 1.0mm aperture), optical detector (miniaturized photomultiplier tube), as well as electronic module (including signal recording, processing and displaying units). This detector is capable of working independently with a cost of ca. $2000 for the whole instrument. The detection limit of the instrument for sodium fluorescein solution is 0.42 nM (S/N=3). The broad applicability of the present system was demonstrated in capillary electrophoresis separation of fluorescein isothiocyanate (FITC) labeled amino acids and in flow cytometry of tumor cells as an on-line LIF detector, as well as in droplet array chip analysis as a LIF scanner. We expect such a compact LIF detector could be applied in flow analysis systems as an on-line detector, and in field analysis and biosensor analysis as a portable universal LIF detector.

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