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2.
Fitoterapia ; 160: 105227, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35662650

RESUMO

A pair of differential epimers with opposite C-7 configurations, crenatosides A and B (1 and 2), and 10 known phenylethanoid glycosides (PhGs) (3-12) were obtained from the succulent stem of Cistanche tubulosa. The structures were elucidated based on extensive spectral data (UV, IR, 1D and 2D NMR, HR-ESIMS), which are first reported natural products with unique glycoside structures. After acid hydrolysis, the configuration of the sugar was determined by comparing it with the normative sugar by HPLC. The absolute configurations of both compounds were determined by ECD spectrum analysis. All the obtained compounds were examined for their inhibitory effect on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in mouse microglial cells (BV-2 cells), and compounds 1 and 2 showed potent inhibition on NO production with IC50 values of 5.62 µM and 6.30 µM, respectively.


Assuntos
Cistanche , Álcool Feniletílico , Animais , Glicosídeos/química , Glicosídeos/farmacologia , Camundongos , Estrutura Molecular , Óxido Nítrico , Álcool Feniletílico/farmacologia , Açúcares
3.
Artigo em Inglês | MEDLINE | ID: mdl-34804177

RESUMO

Breast cancer is one of the most common malignancies in women worldwide. Traditional Chinese medicine has been used as adjunctive or complementary therapy for breast cancer. Diterpenoids from Euphorbia fischeriana Steud. have been demonstrated to possess anti-breast-cancer activity. This research was aimed to systematically explore the diterpenoids from E. fischeriana and study the multiple mechanisms on breast cancer. The structures of diterpenoids were identified by the integrated strategy of UHPLC-Q-TOF-MS and molecular networking. A total of 177 diterpenoids belonging to 13 types were collected. In silico ADME analysis was performed on these compounds. It indicated that 130 of 177 diterpenoids completely adjusted to Lipinski's rule. The targets of compounds were obtained from PharmMapper. The targets of breast cancer were collected from GeneCards. Then, 197 compounds-related targets and 544 breast cancer-related targets were identified. After the intersection process, 58 overlapping targets between compounds-related targets and breast cancer-related targets were acquired. The STRING database was applied to predict the protein-protein interactions. The GO and KEGG pathway enrichment analysis were performed by using the KOBAS database. It indicated that these predicted pathways were closely related to breast cancer. The treatment effect of E. fischeriana on breast cancer might be performed through signaling pathways, such as IL-17 signaling pathway, MAPK signaling pathway, and PI3K-Akt signaling pathway. The predicted top genes such as EGFR, ESR, MAPK, SRC, CASP3, CDK2, and KDR were involved in cell proliferation, gene transcription, apoptosis, signal transduction, DNA damage and repair, tumor differentiation, metastasis, and cell cycle, which indicated that E. fischeriana might treat breast cancer comprehensively. A compounds-KEGG pathways-related targets network was built by using cytoHubba to analyze the hub compounds and targets. It concluded that E. fischeriana treated breast cancer not only by the main components but also by the microconstituents, which reflected the overall regulatory role of multicomponents treating breast cancer. To estimate the binding affinities, binding sites, and binding postures, molecular docking simulations between 177 diterpenoids and top 19 targets were carried out. The results are basically in line with expectations. In conclusion, these results can serve as references for researchers studying potential targets of diterpenoids from E. fischeriana on breast cancer in the future.

4.
Clin Orthop Relat Res ; 479(10): 2228-2235, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33787525

RESUMO

BACKGROUND: Teleradiology has become one of the most important approaches to virtual clinical diagnosis; its importance has only grown during the coronavirus 2019 pandemic. In developing countries, asking patients to take photographs of their images using a smartphone can facilitate the process and help keep its costs down. However, the images taken by patients with smartphones often are of poor quality, and there is no regulation or standard instruction about how to use smartphones to take photographs of medical examination images effectively. These problems limit the use of smartphones in remote diagnosis and treatment. QUESTIONS/PURPOSES: To formulate a set of guidelines for the most appropriate and effective use of smartphones to capture images (radiographs, CT images, and MR images), and to determine whether these guidelines are more effectively adopted by patients of differing ages and genders. METHODS: In this prospective study, a set of step-by-step instructions was created with the goal of helping patients take better smartphone photographs of orthopaedic diagnostic images for transfer to telemedicine services. Following the advice of surgeons, experts in smartphone technology, imaging experts, and suggestions from patients, the instructions were modified based on clinical experience and finalized with the goals of simplicity, clarity, and convenience. Potentially eligible patients were older than 18 years, had no cognitive impairment, and used smart phones. Based on that, 256 participants (patients or their relatives and friends) who visited the orthopaedic department of our hospital from June to October 2020 potentially qualified for this study. A total of 11% (29) declined to participate, leaving 89% (227) for analysis here. Their mean age was 36 ± 11 years, 50% were women (113 of 227), and the patient himself/herself represented in 34% (78 of 227) of participants while relatives or friends of patients made up 66% (149 of 227) of the group. In this study, the diagnoses included spinal stenosis (47% [107 of 227]), disc herniation without spinal stenosis (31% [71 of 227]), vertebral fractures (14% [32 of 227]), and other (7% [17 of 227]). Each study participant first took photographs of their original medical images based on their own knowledge of how to use the smartphone camera function; each participant then took pictures of their original images again after receiving our instructional guidance. Three senior spine surgeons (YZ, TQL, TCM) in our hospital analyzed, in a blinded manner, the instructed and uninstructed imaging files based on image clarity (the content of the image is complete, the text information in the image is clearly visible, there is neither reflection nor shadow in the image) and image position (it is not tilted, curled, inverted, or reversed). If either of these conditions was not satisfied, the picture quality was deemed unacceptable; two of three judges' votes determined the outcome. Interobserver reliability with kappa values for the three judges were 0.89 (YZ versus TQL), 0.92 (YZ versus TCM), and 0.90 (TQL versus TCM). RESULTS: In this study, the overall proportion of smartphone medical images deemed satisfactory increased from 40% (91 of 227) for uninstructed participants to 86% (196 of 227) for instructed participants (risk ratio 2.15 [95% CI 1.82 to 2.55]; p<0.001). The proportion of acceptable-quality images in different age groups improved after instruction, except for in patients aged 51 years or older (3 of 17 uninstructed participants versus 8 of 17 instructed participants; RR 2.67 [95% CI 0.85 to 8.37]; p = 0.07). The proportion of acceptable-quality images in both genders improved after instruction, but there was no difference between the genders. CONCLUSION: We believe our guidelines for patients who wish to take smartphone photographs of their medical images will decrease image transmission cost and facilitate orthopaedic telemedicine consultations. However, it appears that patients older than 50 years are more likely to have difficulty with this approach, and if so, they may benefit from more hands-on assistance from clinic staff or younger relatives or friends. The degree to which our findings are culture-specific should be verified by other studies in other settings, but on the face of it, there is little reason to believe our findings would not generalize to a reasonable degree. Other studies in more heterogeneous populations should also evaluate factors related to levels of educational attainment and wealth differences, but in the meantime, our findings can give clinical teams an idea of which patients may need a little extra assistance. LEVEL OF EVIDENCE: Level II, therapeutic study.


Assuntos
Diagnóstico por Imagem/normas , Fotografação/normas , Smartphone/normas , Telerradiologia/normas , Adulto , COVID-19 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Prospectivos , SARS-CoV-2
5.
Biomed Mater ; 16(3)2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32726758

RESUMO

Clinical evidence indicates the compromised application of titanium implants (TIs) in diabetics, associated with reactive oxygen species (ROS) overproduction at the bone-implant interface. Silk fibroin (SF) has displayed impressive biocompatibility in the application of biomedical material and optimal anti-diabetic effects in oriental medicine. We proposed that SF-coated titanium implants (STIs) could alleviate diabetes-induced compromised osteointegration, which has rarely been reported before. To confirm this hypothesis and explore the underlying mechanisms, rat osteoblasts cultured on 3-dimensional (3D) -printed titanium implants (TIs) and STIs were subjected to normal serum (NS), diabetic serum (DS), DS with N-acetyl-L-cysteine (a ROS inhibitor) or SN50 (an NF-κB inhibitor). Anin vivostudy was performed on diabetic sheep with TIs or STIs implanted into bone defects on thecrista iliaca. The results demonstrated that ROS overproduction induced by diabetes lead to osteoblast dysfunctions and cellular apoptosis on the TI substrate, associated with the activation of an NF-κB signaling pathway in osteoblasts. Importantly, the STI substrate significantly attenuated ROS production and NF-κBp65 phosphorylation, thereby ameliorating the osteoblast biological dysfunctions. These results were further confirmedin vivoby the improved osteointegration of the STIs, as evidenced by Micro-CT and histological examinations compared with those of TIs. These results demonstrated that the ROS-mediated NF-κB signaling pathway played a crucial role in diabetes-induced implant destabilization. Importantly, the SF coating, as a promising material for biomaterial-engineering, markedly improved the clinical treatment effect of TIs under diabetic conditions, possibly associated with the suppression of the NF-κB pathway.


Assuntos
Diabetes Mellitus , Fibroínas , Osseointegração , Próteses e Implantes , Animais , Adesão Celular , Proliferação de Células , NF-kappa B , Porosidade , Impressão Tridimensional , Ratos , Espécies Reativas de Oxigênio/metabolismo , Ovinos , Titânio/farmacologia
6.
Biol Trace Elem Res ; 179(2): 284-293, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28205079

RESUMO

Magnesium has been investigated as a biodegradable metallic material. Increased concentrations of Mg2+ around magnesium implants due to biodegradation contribute to its satisfactory osteogenic capacity. However, the mechanisms underlying this process remain elusive. We propose that activation of the PI3K/Akt signalling pathway plays a role in the Mg2+-enhanced biological behaviours of osteoblasts. To test this hypothesis, 6, 10 and 18 mM Mg2+ was used to evaluate the stimulatory effect of Mg2+ on osteogenesis, which was assessed by evaluating cell adhesion, cell viability, ALP activity, extracellular matrix mineralisation and RT-PCR. The expression of p-Akt was also determined by western blotting. The results showed that 6 and 10 mM Mg2+ elicited the highest stimulatory effect on cell adhesion, cell viability and osteogenic differentiation as evidenced by cytoskeletal staining, MTT assay results, ALP activity, extracellular matrix mineralisation and expression of osteogenic differentiation-related genes. In contrast, 18 mM Mg2+ had an inhibitory effect on the behaviour of osteoblasts. Furthermore, 10 mM Mg2+ significantly increased the phosphorylation of Akt in osteoblasts. Notably, the aforementioned beneficial effects produced by 10 mM Mg2+ were abolished by blocking the PI3K/Akt signalling pathway through the addition of wortmannin. In conclusion, these results demonstrate that 6 mM and 10 mM Mg2+ can enhance the behaviour of osteoblasts, which is at least partially attributed to activation of the PI3K/Akt signalling pathway. Furthermore, a high concentration (18 mM Mg2+) showed an inhibitory effect on the biological behaviour of osteoblasts. These findings advance the understanding of cellular responses to biodegradable metallic materials and may attract greater clinical interest in magnesium.


Assuntos
Magnésio/farmacologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
7.
Biomaterials ; 36: 44-54, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25308520

RESUMO

Chitosan coated porous titanium alloy implant (CTI) is demonstrated a promising approach to improve osseointegration capacity of pure porous titanium alloy implant (TI). Since chitosan has been demonstrated to exhibit antioxidant activity, we propose CTI may ameliorate the ROS overproduction, thus reverse the poor osseointegration under diabetic conditions, and investigate the underlying mechanisms. Primary rat osteoblasts incubated on the TI and the CTI were subjected to normal serum (NS), diabetic serum (DS), DS + NAC (a potent ROS inhibitor) and DS + LY294002 (a PI3K/AKT-specific inhibitor). In vivo study was performed on diabetic sheep implanted with TI or CTI into the bone defects on crista iliaca. Results showed that diabetes-induced ROS overproduction led to osteoblast dysfunction and apoptosis, concomitant with the inhibition of AKT in osteoblasts on the TI substrate. While CTI stimulated AKT phosphorylation through ROS attenuation, thus reversed osteoblast dysfunction evidenced by improved osteoblast adhesion, increased proliferation and ALP activity, and decreased cytotoxicity and apoptotic rate, which exerted same effect to NAC treatment on the TI. These effects were further confirmed by the improved osseointegration within the CTI in vivo evidenced by Micro-CT and histological examinations. In addition, the aforementioned promotive effects afforded by CTI were abolished by blocking PI3K/AKT pathway with addition of LY294002. These results demonstrate that the chitosan coating markedly ameliorates diabetes-induced impaired bio-performance of TI via ROS-mediated reactivation of PI3K/AKT pathway, which elicits a new surface functionalization strategy for better clinical performance of titanium implant in diabetic patients.


Assuntos
Ligas/farmacologia , Quitosana/farmacologia , Diabetes Mellitus Experimental/complicações , Osseointegração/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Titânio/farmacologia , Ligas/química , Animais , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Quitosana/química , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Porosidade , Próteses e Implantes , Ratos , Ratos Sprague-Dawley , Ovinos , Transdução de Sinais , Titânio/química
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