Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Front Med (Lausanne) ; 10: 1249672, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38188338

RESUMO

Objective: This study investigates the effectiveness of repetitive transcranial magnetic stimulation (rTMS) as a biophysical therapy for alleviating symptoms of functional bowel disorder (FBD) and associated psychological symptoms by targeting the brain-gut axis. Methods: We conducted a comparative analysis involving 226 subjects, comprising the FBD group (n = 113) and a healthy control group (n = 113). Within the FBD group, participants were further divided into those who received rTMS therapy (FBD treatment group, n = 63) and those who did not (FBD control group, n = 50). The FBD treatment group was subcategorized based on the number of rTMS treatments received. We evaluated various factors, including gender, age, monthly household income, daily activity level, and sleep quality, as potential risk factors for FBD. Severity assessments of FBD and associated symptoms (constipation, anxiety, depression, and somatization disorders) were conducted using validated scales before and after treatment. Results: Our findings revealed a higher incidence of FBD in women, with most cases emerging at age 50 or older. We identified lower monthly household income, reduced daily activity levels, and poorer sleep quality as factors associated with a higher likelihood of FBD. FBD patients exhibited higher scores for constipation, anxiety, depression, and somatization disorders compared to healthy controls. rTMS therapy was effective in reducing gastrointestinal symptoms, anxiety, depression, and somatization disorders among FBD patients. Notably, the extent of improvement was positively correlated with the number of rTMS sessions. No adverse effects were observed during the study. Conclusion: Our study underscores the efficacy of biophysical therapy, specifically repetitive transcranial magnetic stimulation, in mitigating FBD symptoms and associated psychological distress. The treatment's effectiveness is positively linked to the frequency of rTMS sessions.

2.
Nat Chem Biol ; 18(11): 1253-1262, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36229681

RESUMO

Fungal transcription factor Upc2 senses ergosterol levels and regulates sterol biosynthesis and uptake. Constitutive activation of Upc2 causes azole resistance in Candida species. We determined the structure of ergosterol-bound Upc2, revealing the ligand specificity and transcriptional regulation. Ergosterol binding involves conformational changes of the ligand-binding domain, creating a shape-complementary hydrophobic pocket. The conserved helix α12 and glycine-rich loop are critical for sterol recognition by forming the pocket wall. The mutations of the glycine-rich loop inhibit ligand binding by steric clashes and constitutively activate Upc2. The translocation of Upc2 is regulated by Hsp90 chaperone in a sterol-dependent manner. Ergosterol-bound Upc2 associates with Hsp90 using the C-terminal tail, which retains the inactive Upc2 in the cytosol. Ergosterol dissociation induces a conformational change of the C-terminal tail, releasing Upc2 from Hsp90 for nuclear transport by importin α. The understanding of the regulatory mechanism provides an antifungal target for the treatment of azole-resistant Candida infections.


Assuntos
Antifúngicos , Azóis , Azóis/farmacologia , Antifúngicos/farmacologia , Farmacorresistência Fúngica/genética , Esteróis , Ligantes , alfa Carioferinas/genética , alfa Carioferinas/metabolismo , Ergosterol/genética , Ergosterol/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Glicina/metabolismo , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica
3.
Drug Deliv ; 25(1): 1302-1318, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29869524

RESUMO

Currently, combination drug therapy is one of the most effective approaches to glioma treatment. However, due to the inherent dissimilar pharmacokinetics of individual drugs and blood brain barriers, it was difficult for the concomitant drugs to simultaneously be delivered to glioma in an optimal dose ratio manner. Herein, a cationic micellar core (Cur-M) was first prepared from d-α-tocopherol-grafted-ε-polylysine polymer to encapsulate the hydrophobic curcumin, followed by dopamine-modified-poly-γ-glutamic acid polymer further deposited on its surface as a anion shell through pH-sensitive linkage to encapsulate the hydrophilic doxorubicin (DOX) hydrochloride. By controlling the combinational Cur/DOX molar ratio at 3:1, a pH-sensitive core-shell nanoparticle (PDCP-NP) was constructed to simultaneously target the cancer stem cells (CSCs) and the differentiated tumor cells. PDCP-NP exhibited a dynamic diameter of 160.8 nm and a zeta-potential of -30.5 mV, while its core-shell structure was further confirmed by XPS and TEM. The ratiometric delivery capability of PDCP-NP was confirmed by in vitro and in vivo studies, in comparison with the cocktail Cur/DOX solution. Meanwhile, the percentage of CSCs in tumors was significantly decreased from 4.16% to 0.95% after treatment with PDCP-NP. Overall, PDCP-NP may be a promising carrier for the combination therapy with drug candidates having dissimilar physicochemical properties.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/química , Glioma/tratamento farmacológico , Nanopartículas/química , Animais , Linhagem Celular Tumoral , Curcumina/administração & dosagem , Curcumina/química , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Ácido Glutâmico/química , Humanos , Concentração de Íons de Hidrogênio , Masculino , Micelas , Células-Tronco Neoplásicas/efeitos dos fármacos , Polilisina/química , Polímeros/química , Ratos , Ratos Sprague-Dawley , alfa-Tocoferol/química
4.
Colloids Surf B Biointerfaces ; 160: 704-714, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29035818

RESUMO

A poor percutaneous penetration capability for most topical anti-inflammatory drugs is one of the main causes compromising their therapeutic effects on psoriatic skin. Even though curcumin has shown a remarkable efficacy in the treatment of psoriasis, its effective penetration through the stratum corneum is still a major challenge during transdermal delivery. The aim of our study was to design skin-permeating nanoparticles (NPs) to facilitate delivery of curcumin to the deeper layers of the skin. A novel amphiphilic polymer, RRR-α-tocopheryl succinate-grafted-ε-polylysine conjugate (VES-g-ε-PLL) was synthesized and self-assembled into polymeric nanoparticles. The nanoparticles of VES-g-ε-PLL exhibiting an ultra-small hydrodynamic diameter (24.4nm) and a positive Zeta potential (19.6mV) provided a strong skin-penetrating ability in vivo. Moreover, curcumin could effectively be encapsulated in the polymeric nanoparticles with a drug loading capacity of 3.49% and an encapsulating efficiency of 78.45%. In order to prolong the retention time of the ultra-small curcumin-loaded nanoparticles (CUR-NPs) in the skin, silk fibroin was used as a hydrogel-based matrix to further facilitate topical delivery of the model drug. In vitro studies showed that CUR-NPs incorporated in silk fibroin hydrogel (CUR-NPs-gel) exhibited a slower release profile of curcumin than the plain CUR-gel, without compromising the skin penetration ability of CUR-NPs. In vivo studies on miquimod-induced psoriatic mice showed that CUR-NPs-gel exhibited a higher therapeutic effect than CUR-NPs as the former demonstrated a more powerful skin-permeating capability and a more effective anti-keratinization process. CUR-NPs-gel was therefore able to inhibit the expression of inflammatory cytokines (TNF-α, NF-κB and IL-6) to a greater extent. In conclusion, the permeable nanoparticle-gel system may be a potential carrier for the topical delivery of lipophilic anti-psoriatic drugs.


Assuntos
Curcumina/administração & dosagem , Fibroínas/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Nanopartículas/química , Psoríase/tratamento farmacológico , Pele/metabolismo , Administração Cutânea , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacocinética , Curcumina/química , Curcumina/farmacocinética , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos/métodos , Humanos , Masculino , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Tamanho da Partícula , Polímeros/química , Psoríase/patologia , Seda/química
5.
Colloids Surf B Biointerfaces ; 158: 295-307, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28711016

RESUMO

Severe toxicity and poor tumour penetration are two intrinsic limited factors to hinder the broad clinical application for most of first-line chemotherapeutics. In this study, a novel vitamin E succinate-grafted ε-polylysine (VES-g-PLL) polymer was synthesized by using ε-polylysine as backbone. By adjusting VES graft ratio, VES-g-PLL (50) with a theoretic VES graft ratio of 50% could self-assemble into a supermolecular micelle with a hydrodynamic diameter (Dh) of ca.20nm, and Zeta potential of 19.6mV. VES-g-PLL micelles themselves displayed a strong anti-tumour effect on glioma. The poorly water-soluble curcumin was effectively encapsulated in VES-g-PLL micelles with the drug loading amount and entrapment efficiency reaching 4.32% and 82.27%, respectively. In a physiologic medium, curcumin-loaded VES-g-PLL micelles (Cur-Micelles) not only remained stable without obvious drug leakage but also sustained the release of its encapsulated curcumin for a long time. Because of the ultra-small size and positively-charged surface, Cur-Micelles penetrated the deeper tumour zone than free curcumin, resulting in a significant inhibition of tumour spheroids growth. Moreover, in vivo strong antitumor effect of Cur-Micelles was also exhibited at assistance of ultrasound-targeted microbubble destruction and the real-time MRI imaging demonstrated a nearly complete suppression of glioma after 28days of treatment. TUNEL staining showed that the therapeutic mechanism of Cur-Micelles was relevant to the apoptosis of tumour cells. Finally, in vivo nontoxicity of Cur-Micelles against normal organs including heart, liver, spleen, lung and kidney tissues was also demonstrated by the HE staining. In conclusion, VES-g-PLL micelles may serve as a potential carrier for curcumin to enhance tumour penetration and improve therapeutic effect on glioma.


Assuntos
Curcumina/química , Micelas , Polilisina/química , Apoptose/efeitos dos fármacos , Curcumina/farmacologia , Glioma/metabolismo , Humanos , Marcação In Situ das Extremidades Cortadas , Rim/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Células MCF-7 , Baço/metabolismo , alfa-Tocoferol/análogos & derivados , alfa-Tocoferol/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA