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1.
Molecules ; 29(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38474619

RESUMO

Houttuyniae herba has a long history of medicinal and edible homology in China. It has the functions of clearing heat and detoxifying, reducing swelling and purulent discharge, diuresis, and relieving gonorrhea. It is mainly distributed in the central, southeastern, and southwestern provinces of China. Houttuyniae herba has been designated by the National Ministry of Health of China as a dual-use plant for both food and medicine. Comprising volatile oils, flavonoids, and alkaloids as its primary constituents, Houttuyniae herba harbors aristolactams, a prominent subclass of alkaloids. Notably, the structural affinity of aristolactams to aristolochic acids is discernible, the latter known for its explicit toxicological effects. Additionally, the safety study on Houttuyniae herba mainly focused on the ethanol, methanol, or aqueous extract. In this study, both zebrafish and mice were used to evaluate the acute toxicity of the total alkaloids extracts from Houttuyniae herba (HHTAE). The zebrafish experiment showed that a high concentration (0.1 mg/mL) of HHTAE had a lethal effect on zebrafish embryos. Furthermore, the mice experiment results showed that, even at a higher dose of 2000 mg/kg, HHTAE was not toxic. In conclusion, HHTAE was of low safety risk.


Assuntos
Alcaloides , Antineoplásicos , Medicamentos de Ervas Chinesas , Óleos Voláteis , Camundongos , Animais , Peixe-Zebra , Extratos Vegetais , Medicamentos de Ervas Chinesas/química
2.
ACS Appl Mater Interfaces ; 15(38): 45388-45398, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37705159

RESUMO

Polyurethane (PU) with microphase separation has garnered significant attention due to its highly designable molecular structure and a wide range of adjustable properties. However, there is currently a lack of systematic approaches for quantifying PU's microphase separation. To address this research gap, we utilized an atomic force microscopy (AFM) nanomechanical mapping technique along with Gaussian fitting to recolor and quantitatively analyze the evolution of PU's microphase separation. By varying the ratios of the chain extender to cross-linking agent, we observed the changes in the hydrogen bonding between the soft and hard segments. As the ratio of the chain extender to cross-linking agent decreases, the strength of the hydrogen bonding weakens, resulting in a reduction in the quantity and phase percentage of hard segment (HS) domains. Consequently, the degree of microphase separation between the soft and hard segments decreases, leading to specific alterations in the material's mechanical properties and dynamic viscoelasticity. To further investigate the hierarchical structure of PU, we employed various techniques, such as X-ray analysis, transmission electron microscopy (TEM), and AFM-based infrared spectroscopy (AFM-IR). Our findings reveal a spherulite pattern composed of lamellae within the HS domains, with the cross-linking density gradually increasing from the center to the periphery. Overall, our comprehensive characterization of PU provides valuable insights into its hierarchical structure and establishes a quantitative framework to explore the intricate relationship between the structure and properties.

3.
ACS Appl Mater Interfaces ; 15(30): 36759-36770, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37477654

RESUMO

The development of degradable, cost-effective, and eco-friendly ionic conductive gels is highly required to reduce electronic waste originating from flexible electronic devices. However, biocompatible, degradable, tough, and durable conductive gels are challenging to achieve. Herein, we develop a facile strategy for the design and synthesis of degradable tough eutectogels by integrating an electrostatically driven supramolecular network composed of branched polyacrylic acid (PAA) and monoethanolamine (MEA) into a green deep eutectic solvent with chitosan quaternary ammonium salt (CQS). The specially designed PAA/MEA/CQS eutectogels present multiple desired properties, including high transparency, widely adjustable mechanical properties, high resilience, reliable adhesiveness, excellent self-healing ability, good conductivity, remarkable anti-freezing performance, and antibacterial properties. The dynamic and reversible supramolecular interactions not only significantly enhance the mechanical properties of the PAA/MEA/CQS eutectogels but also enable fast degradation, addressing the dilemma between mechanical strength and degradability. More importantly, a biocompatible and degradable multifunctional ionic skin is successfully fabricated based on the PAA/MEA/CQS eutectogel, exhibiting high sensitivity, a wide sensing range, and a rapid response speed toward strain, pressure, and temperature. Thus, this study offers a promising strategy for fabricating degradable tough eutectogels, which show great potential as high-performance ionic skins for next-generation flexible wearable electronic devices.


Assuntos
Pele , Íons/química , Pele/química , Antibacterianos/química , Cicatrização , Adesividade , Géis/química , Materiais Biocompatíveis/química , Humanos
4.
Molecules ; 27(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36558101

RESUMO

Houttuyniae herba, the Saururaceae plant Houttuynia cordata Thunb., has multiple therapeutic effects, including clearing heat, eliminating toxins, reducing swelling, discharging pus, and relieving stagnation. It has a long history as an edible and medicinal plant in China. Phytochemical studies show that the main constituents include volatile oil, flavonoids, and alkaloids. Aristolactam is a major alkaloid with a structure similar to toxic aristolochic acids. However, there has been no systematic study on aristolochic acids and alkaloids in Houttuyniae herba. Therefore, in this study, an LC-MS/MS method was developed to simultaneously detect seven alkaloids and five aristolochic acids in Houttuyniae herba from different origins. Six alkaloids (O-demethyl nornucifrine, N-nornucifrine, aristololactam AII, aristololactam FI, aristololactam BII, cepharadione B) were found and quantitatively determined in 75 batches of samples. Meanwhile, no aristolochic acids or aristololactams were found in Houttuyniae herba at a limit of detection (LOD) of ≤4 ng/mL. The method developed was fully validated in terms of LOD, limit of quantification (LOQ), linearity, precision, accuracy, and stability. These data clarify the content of the above safety-related components in Houttuyniae herba and provide a reference for further research into its safety.


Assuntos
Alcaloides , Medicamentos de Ervas Chinesas , Plantas Medicinais , Cromatografia Líquida , Medicamentos de Ervas Chinesas/química , Espectrometria de Massas em Tandem/métodos , Alcaloides/química , Cromatografia Líquida de Alta Pressão/métodos
5.
Macromol Rapid Commun ; 43(21): e2200480, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35946394

RESUMO

Ionogels have attracted intensive attentions as promising flexible conductive materials. However, simultaneous integration of excellent mechanical properties, high conductivity, outstanding self-healing ability, and strong adhesiveness is still challenging. Here, an ingenious composition design is proposed to address this long-standing challenge of ionogels. High-performance PEI/PAA/CMC ionogels, consist of a loosely cross-linked poly(acrylic acid) (PAA) network, dynamically cross-linked network based on polycationic polyethyleneimine (PEI) and polyanionic PAA, and carboxymethyl cellulose (CMC) reinforcing filler, are formed in a deep eutectic solvent (DES) composed of choline chloride and urea. Benefiting from the loose PAA network and dynamic noncovalent interactions, ionogels with both highly enhanced mechanical robustness and excellent conductivity are obtained at high loading of DES, overcoming the strength-ductility/conductivity trade-off dilemma. By adjusting PEI/PAA mass ratio, the tensile strength and strain of PEI/PAA/CMC ionogels are effectively controlled in a wide range of 0.15-7.9 MPa and 232-1161%, respectively, while maintaining the desirable conductivity of ≈10-4 S cm-1 . Besides, healed tensile strength over 2.1 MPa and adhesion strength up to 0.2 MPa are achieved for the PEI0.06 /PAA0.25 /CMC0.01 ionogel. The delicate design strategy provides a feasible approach to prepare ionogels with outstanding comprehensive performance, which have potential for applications in flexible electronics.

6.
Cancers (Basel) ; 14(3)2022 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-35159091

RESUMO

Background: Survival of patients with stage I non-small cell lung cancer (NSCLC) varies greatly. We sought to explore whether presence of oncogenic alterations in histologically-negative lymph nodes (LNs) can be of prognostic significance in stage I lung adenocarcinoma (LUAD). Methods: Genomic analysis of oncogenic alterations was applied to 123 stage I LUAD tumors. The same genomic variants identified in primary tumors were examined in corresponding histologically-negative LNs. Results: A total of 102 (82.9%) patients had at least one canonical oncogenic alteration detected in primary tumors, and 57 LNs from 12 patients (11.8%) were found to carry the identical oncogenic alterations detected in the corresponding primary tumor tissues, including EGFR mutations (six cases), KRAS mutations (three cases), ALK fusion (one case), BRAF mutation (one case) and HER2 & NRAS co-mutations (one case). None of these LNs was found to have occult tumor cells by routine pathological assessment or immunohistochemistry staining using antibodies against pan-cytokeratins (AE1/AE3) and the epithelial marker Ber-EP4. The detection rate of oncogenenic alterations in LN was significantly higher in RAS-mutant tumors than EGFR mutant tumors (36.36% verse 7.41%, p = 0.017). Patients with oncogenic alterations in LN showed inferior disease-free survival (DFS, p = 0.025) and overall survival (OS, p = 0.027). Furthermore, patients with RAS-mutations detected in LN had the worst DFS and OS (p = 0.001). Among the 11 patients with RAS mutation in primary tumors, DFS and OS in the four patients with mutations detected in LN were significantly shorter than the remaining seven patients without mutations LN (DFS, p = 0.001, OS, p = 0.002). Conclusions: Genomic analysis has the potential to detect oncogenic alterations in regional LNs for localized LUAD and presence of oncogenic alterations in regional LN may be associated with inferior clinical outcome of stage I LUAD, particularly for certain molecular subgroups. ClinicalTrials.gov ID NCT04266691.

7.
Proc Natl Acad Sci U S A ; 117(40): 25036-25042, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32943537

RESUMO

Minimally invasive testing for early detection of lung cancer to improve patient survival is a major unmet clinical need. This study aimed to develop and validate a serum multi-microRNA (multimiR) panel as a minimally invasive test for early detection of nonsmall cell lung cancer (NSCLC) regardless of smoking status, gender, and ethnicity. Our study included 744 NSCLC cases and 944 matched controls, including smokers and nonsmokers, male and female, with Asian and Caucasian subjects. Using RT-qPCR and a tightly controlled workflow, we quantified the absolute expression of 520 circulating microRNAs (miRNAs) in a Chinese cohort of 180 early stage NSCLC cases and 216 healthy controls (male smokers). Candidate biomarkers were verified in two case-control cohorts of 432 Chinese and 218 Caucasians, respectively (including females and nonsmokers). A multimiR panel for NSCLC detection was developed using a twofold cross-validation and validated in three additional Asian cohorts comprising 642 subjects. We discovered 35 candidate miRNA biomarkers, verified 22 of them, and developed a five-miR panel that detected NSCLC with area under curve (AUC) of 0.936-0.984 in the discovery and verification cohorts. The panel was validated in three independent cohorts with AUCs of 0.973, 0.916, and 0.917. The sensitivity of five-miR test was 81.3% for all stages, 82.9% for stages I and II, and 83.0% for stage I NSCLC, when the specificity is at 90.7%. We developed a minimally invasive five-miR serum test for detecting early stage NSCLC and validated its performance in multiple patient cohorts independent of smoking status, gender, and ethnicity.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Detecção Precoce de Câncer , MicroRNAs/sangue , Adulto , Idoso , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade
8.
Ann Transl Med ; 8(6): 316, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32355760

RESUMO

BACKGROUND: TP53 is frequently altered in esophageal squamous cell carcinoma (ESCC). However, the landscape of TP53 mutation and its effects on patients remain controversial. METHODS: Somatic mutations of TP53 in 161 patients with resectable ESCC were identified by next-generation sequencing (NGS) and verified by immunohistochemistry (IHC). Patients were stratified into seven TP53 mutations, and depending on the extent of the effect on the encoded protein, it was divided into "disruptive" and "non-disruptive" types. The association of TP53 mutation with clinicopathological properties and disease outcome was investigated. RESULTS: TP53 mutations were discovered in 85.7% patients, of which 68.9% carried mutations in the DNA-binding domain (DBD). A total of 47.8% and 37.9% patients had disruptive and non-disruptive TP53 mutations, respectively. Most patients carried only one TP53 mutation, but 15.5% had double mutations. TP53 mutations were dominant in exons 5 to 8. Missense mutation was the most frequent (97/163, 59.5%), and the top five frequently occurring variations included R273X, Y220X, H193, H179X, and R175H. Multivariable analysis revealed non-disruptive mutation in TP53 DBD as the independent prognostic predictor for progression-free survival (PFS) and overall survival (OS). The expression of p53 positively correlated with non-disruptive mutation in DBD. Patients with high p53 protein expression showed better outcomes. CONCLUSIONS: Non-disruptive mutation in TP53 DBD serves as an independent beneficial prognostic factor of prolonged survival in resectable ESCC.

9.
Ann Surg Oncol ; 26(12): 3912-3919, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31359285

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) patients who achieve a pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC) have better prognoses. OBJECTIVE: This study aimed to develop an intuitive nomogram based on simple laboratory indexes to predict the pCR of standard NAC in TNBC patients. METHODS: A total of 80 TNBC patients who received eight cycles of thrice-weekly standard NAC (anthracycline and cyclophosphamide followed by taxane) and subsequently underwent surgery in Zhejiang Cancer Hospital were retrospectively enrolled, and data on their pretreatment clinical features and multiple simple laboratory indexes were collected. The optimal cut-off values of the laboratory indexes were determined by the Youden index using receiver operating characteristic (ROC) curve analyses. Forward stepwise logistic regression (likelihood ratio) analysis was applied to identify predictive factors for a pCR of NAC. A nomogram was then developed according to the logistic model, and internally validated using the bootstrap resampling method. RESULTS: pCR was achieved in 39 (48.8%) patients after NAC. Multivariate analysis identified four independent indicators: clinical tumor stage, lymphocyte to monocyte ratio, fibrinogen level, and D-dimer level. The nomogram established based on these factors showed its discriminatory ability, with an area under the curve (AUC) of 0.803 (95% confidence interval 0.706-0.899) and a bias-corrected AUC of 0.771. The calibration curve and Hosmer-Lemeshow test showed that the predictive ability of the nomogram was a good fit to actual observation. CONCLUSIONS: The nomogram proposed in the present study exhibited a sufficient discriminatory ability for predicting pCR of NAC in TNBC patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/análise , Quimioterapia Adjuvante/métodos , Terapia Neoadjuvante/métodos , Nomogramas , Neoplasias de Mama Triplo Negativas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Estudos Retrospectivos , Taxa de Sobrevida , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo
10.
J Transl Med ; 16(1): 310, 2018 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-30419922

RESUMO

BACKGROUND: Brain metastasis is an extremely serious sequela with a dismal prognosis in non-small cell lung cancer (NSCLC). The present study aimed to identify novel biomarkers and potential therapeutic targets for brain metastases of NSCLC. METHODS: We performed high-throughput Luminex assays to profile the transcriptional levels of 36 genes in 70 operable NSCLC patients, among whom 37 developed brain metastases as the first relapse within 3 years after surgery. The Cox proportional hazards regression model was used to evaluate the association between genes and brain metastases. Wound healing assay and transwell assay was carried out to estimate the function of target gene in vitro. And left ventricular injection on nude mice was used to evaluate the effect of target gene in vivo. RESULTS: Growth-associated protein 43 (GAP43) was found to be related to brain metastasis. Multivariate Cox regression analysis showed that NSCLC patients with elevated GAP43 had a 3.29-fold increase in the risk for brain metastasis compared with those with low levels (95% confidence interval: 1.55-7.00; P = 0.002). Kaplan-Meier survival curves revealed that GAP43 was also associated with overall survival. Analysis of a cohort of 1926 NSCLC patients showed similar results: patients with high levels of GAP43 had worse progression-free and overall survival rates. Furthermore, in vitro experiments showed that GAP43 facilitated cell migration. Animal studies demonstrated that GAP43-silenced NSCLC cells were less likely to metastasize to the brain and bone than control cells. Immunofluorescence and F-actin/G-actin in vivo assays indicated that GAP43 knockdown triggered depolymerization of the F-actin cytoskeleton. Rho GTPase activation assays showed that Rac1 was deactivated after GAP43 was silenced. CONCLUSIONS: Our findings suggest that GAP43 is an independent predictor of NSCLC brain metastasis and that it may facilitate metastasis by regulating the Rac1/F-actin pathway.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Proteína GAP-43/metabolismo , Neoplasias Pulmonares/patologia , Actinas/metabolismo , Idoso , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Feminino , Proteína GAP-43/genética , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/genética , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Polimerização , Modelos de Riscos Proporcionais
11.
Front Microbiol ; 9: 1288, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29967599

RESUMO

In this study, one of the dominant pathogens, which caused postharvest diseases such as anthracnose, was isolated from decayed 'Hongyang' kiwifruit. It was identified as Colletotrichum acutatum by its morphological characteristics and standard internal transcribed spacer ribosomal DNA sequence. Further, the efficacy and possible mechanism of cinnamon essential oil on inhibition of C. acutatum were investigated. Results showed that C. acutatum was dose-dependently inhibited by cinnamon essential oil. Meanwhile, the mycelial growth and spore germination of C. acutatum were completely inhibited at the concentrations of 0.200 µL/mL and 0.175 µL/mL (v/v), respectively. Indeed, both minimal inhibitory and minimum fungicidal concentrations of cinnamon essential oil were measured as 0.200 µL/mL. Additionally, the possible antifungal mechanism of cinnamon essential oil on C. acutatum was demonstrated. Results showed that the cinnamon essential oil could destroy the cell membrane integrity of C. acutatum, and the structure of cell membrane was changed. Indeed, the cell cytoplasm including soluble protein, sugar, and nucleic acid was released, which significantly changed the extracellular conductivity. Results suggested that the cinnamon essential oil exerted great potential to be used as a natural and efficient preservative for kiwifruit postharvest storage, which were helpful for the better understanding of the efficacy and mechanism of cinnamon essential oil on inhibition of pathogens isolated from decayed 'Hongyang' kiwifruit.

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