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1.
Sensors (Basel) ; 22(24)2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36560208

RESUMEN

This study analyzes the magnetic field wave characteristics of a wireless power transfer (WPT) system from a time-varying view in the nonradiative near field. Phenomena of both forward and backward traveling waves were found. These wave phenomena refer to magnetoinductive waves (MIWs) according to the findings in this study and MIW theory and characteristics. A traditional MIW only appears in the MIW waveguide, which is always constructed by many parallel coils. However, this study analyzed MIWs in a two-coil WPT system, proving that MIWs exist not only in a multi-coil system but also in a basic two-coil system. The velocity of MIWs, a kind of a phase velocity, was calculated. An approximate equation for evaluating wave velocity is proposed. Furthermore, the MIWs in the two-coil WPT system were extended into a more general situation. In this general situation, two separated standing waves were set, and a traveling wave was generated by those two standing waves. The result explains the mechanisms of MIWs in a general situation from a time-varying view. Lastly, a simulation was conducted to verify the accuracy of the study. The results demonstrated that MIWs exist, and the approximate equation is correct. This study presents a novel view on the mechanisms of the WPT system from a wave view.

2.
Pharm Biol ; 60(1): 1449-1457, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35938505

RESUMEN

CONTEXT: A novobiocin derivative, XN4, has been shown to promote cell apoptosis in chronic myeloid leukaemia. OBJECTIVE: This study explores the mechanism by which XN4 promotes ferroptosis of gastric cancer (GC) cells. MATERIALS AND METHODS: Human GC SGC-7901 and BGC-823 cells were treated with different XN4 concentrations (0, 0.1, 0.5, 1.0, 5.0, and 10.0 µmol/L) to evaluate effects of XN4. Additionally, cells were pre-treated for 24 h with si-NOX4, for 1 h with the iron chelator deferoxamine mesylate (DFO) or for 1 h with the lipid peroxidation inhibitor liproxstatin-1 before being treated with XN4 to analyse the mechanism of XN4. RESULTS: XN4 increased cell death (IC50 values of XN4 on SGC-7901 and BGC-823 cells: 1.592 ± 0.14 µmol/L and 2.022 ± 0.19 µmol/L) and Fe2+ levels in SGC-7901 and BGC-823 cells. These effects of 2.0 µmol/L XN4 were abolished by 100 µmol/L DFO treatment. XN4 enhanced transferrin and transferrin receptor expression to induce Fe2+ accumulation. XN4 decreased mitochondrial membrane potentials in GC cells, similar to erastin. Additionally, XN4 increased MDA, hydrogen peroxide, and ROS levels, but diminished total glutathione levels. Liproxstatin-1 (200 nmol/L) nullified the effects of XN4 (2.0 µmol/L) on MDA levels and cell death. Moreover, GPX4 levels decreased, but NOX4 and ferroptosis-related protein PTGS2 levels increased in GC cells following XN4 treatment, which was nullified by NOX4 knockdown. DISCUSSION AND CONCLUSIONS: The pro-ferroptotic role of XN4 in GC might enable it to become a promising drug for GC treatment in the future despite the need for extensive research.


Asunto(s)
Ferroptosis , Neoplasias Gástricas , Apoptosis , Muerte Celular , Humanos , Peroxidación de Lípido , NADPH Oxidasa 4/metabolismo , NADPH Oxidasa 4/farmacología , Novobiocina/farmacología , Especies Reactivas de Oxígeno/metabolismo , Neoplasias Gástricas/tratamiento farmacológico
3.
Clin Lab ; 65(7)2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31307182

RESUMEN

BACKGROUND: The Mindray SAL 8000 is an integrated serum analyzer for photometric, electrochemical, and im-munological assays. The technical, analytical, and workflow performance of the system were evaluated in this study. METHODS: The technical evaluation was performed using protocols adopted from the guidelines of the China Food and Drug Administration (CFDA). The precision, linearity, interference, and method comparison were carried out according to the Clinical and Laboratory Standards Institute (CLSI) protocols. The verification of carryover and turnaround time were conducted using specimens containing different analytes. RESULTS: The technical performance was acceptable for all evaluated aspects. The repeatability and within-labora-tory coefficients of variation (CVs) ranged between 0.22% and 4.23% for routine chemistry and between 1.05% and 6.89% for immunochemistry, respectively. All evaluated analytes exhibited linearity over the ranges claimed by the manufacturer. Significant interferences were observed during low concentration TBIL and P measure-ments due to the presence of lipemia. Method comparisons showed good agreement with the comparison systems and with the correlation coefficients ≥ 0.988 except for anti-HBs (r = 0.812). No significant intra-module and inter-module carryovers were detected. For all the 1,220 samples, 25%, 54%, 63%, 79%, 91%, and 100% samples com-pleted analysis in 16.3 minutes, 30 minutes, 60 minutes, 120 minutes, 180 minutes, and 320 minutes, respectively. CONCLUSIONS: The Mindray SAL 8000 integrated system achieved optimal technical performance and met most of the criteria regarding analytical performance. The workflow study of the system met the turnaround time (TAT) requirements of laboratories. Therefore, it is a good candidate to be used in medium and large-sized laboratories.


Asunto(s)
Química Clínica/métodos , Técnicas de Laboratorio Clínico/métodos , Inmunoensayo/métodos , Pruebas Inmunológicas/métodos , Química Clínica/normas , Técnicas de Laboratorio Clínico/normas , Humanos , Inmunoensayo/normas , Pruebas Inmunológicas/normas , Reproducibilidad de los Resultados
4.
J Cell Biochem ; 119(2): 1855-1865, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28802012

RESUMEN

Pancreatic cancer is one of the major human malignant tumors severely endangering human health and life with high mortality due to the concealment of early symptoms and lack of effective therapies during advanced stages. The identification of pancreatic cancer stem cell functions has been as important strategy for understanding of pancreatic cancer biology and novel drug and therapy development. In the present study, we successfully isolated the pancreatic sphere-forming cells from pancreatic cancer cell line PANC-1 by sphere-forming method and we found that the sphere-forming ability and the cell migration rate of pancreatic sphere-forming cells were significantly inhibited by 5,7-DMF treatment, which was supported by the corresponding changes of several EMT biomarkers after being treated with 5,7-DMF. Moreover, we revealed here that the inhibition of pancreatic sphere-forming cells was mediated by the expression of FoxM1 gene, and also the expression of SOX2 gene was regulated by FoxM1 in pancreatic sphere-forming cells and involved in the inhibitory role of 5,7-DMF. These results provided important basis for the application of 5,7-DMF as a novel drug candidate for the pancreatic cancer treatment.


Asunto(s)
Flavonoides/farmacología , Proteína Forkhead Box M1/genética , Neoplasias Pancreáticas/genética , Factores de Transcripción SOXB1/genética , Esferoides Celulares/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular , Ensayos de Selección de Medicamentos Antitumorales , Transición Epitelial-Mesenquimal , Proteína Forkhead Box M1/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/metabolismo , Factores de Transcripción SOXB1/metabolismo , Esferoides Celulares/metabolismo
5.
Hepatology ; 57(6): 2326-37, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23325674

RESUMEN

UNLABELLED: Epithelial-mesenchymal transition (EMT) is a critical step in the metastasis of hepatocellular carcinoma (HCC). BTB/POZ domain-containing protein 7 (BTBD7) regulates EMT-associated proteins implicated in HCC progression. However, the role(s) of BTBD7 in HCC have not been identified. Using highly metastatic HCC HCCLM3 cells, immortalized L02 hepatocytes, metastatic HCC animal models, and three independent cohorts of HCC patient specimens, we aimed to determine the involvement of BTBD7 in HCC metastasis. We show that BTBD7 messenger RNA and protein was highly expressed in HCC cells and tumor tissues, with such expression being associated with: enhanced cell motility, venous invasion, and poor prognosis. BTBD7 promoted HCC angiogenesis and metastasis in vitro and in vivo, but did not influence cell proliferation or colony formation. BTBD7 enhancement of HCC invasion and EMT phenotype occurred through activation of a RhoC-Rock2-FAK-signaling pathway, resulting in matrix metalloproteinase-2/9 production and microvessel formation. Applying a predictive risk score model, Cox regression analysis revealed that high BTBD7 expression integrated with high microvessel density was a powerful independent predictive factor of HCC clinical outcome. CONCLUSION: The present study identifies BTBD7 as a novel candidate prognostic factor and a potential therapeutic target of HCC. (HEPATOLOGY 2013; 57:2326-2337).


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , Recurrencia Local de Neoplasia/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Animales , Carcinoma Hepatocelular/diagnóstico , Transición Epitelial-Mesenquimal , Células Hep G2 , Humanos , Neoplasias Hepáticas/diagnóstico , Masculino , Metaloproteinasas de la Matriz/metabolismo , Ratones , Ratones Endogámicos BALB C , Metástasis de la Neoplasia , Neovascularización Patológica , Pronóstico , Modelos de Riesgos Proporcionales , Transducción de Señal , Proteínas de Unión al GTP rho/metabolismo , Proteína rhoC de Unión a GTP
6.
J Gastrointest Oncol ; 15(2): 612-629, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38756644

RESUMEN

Background: Several studies demonstrated trifluridine/tipiracil (TAS-102) plus bevacizumab (BEV) had better efficacy than the monotherapy of TAS-102 in refractory metastatic colorectal cancer (mCRC). However, it remains unclear whether Chinese population can benefit from this combination or not. Hence, we conducted this retrospective cohort study to compare the efficacy and safety between TAS-102 plus BEV with TAS-102 monotherapy in refractory mCRC. Methods: This retrospective cohort study enrolled patients (any age) with refractory mCRC from Hunan Cancer Hospital. The main inclusion criteria were histopathologically and/or radiographically confirmed refractory mCRC, World Health Organization (WHO) performance status of 0 to 2, adequate organ function, and initial treatment of TAS-102 with or without BEV between November 2020 and October 2022. Previous therapy with fruquintinib or regorafenib was allowed but not mandatory. Baseline demographic and clinical characteristics were collected appropriately. Every 2 or 3 treatment cycles, the patients were assessed by computed tomography (CT) scans and clinical assessments until disease progression or loss to follow-up. The National Cancer Institute Common Terminology Criteria for Adverse Events 5.0 (NCI-CTCAE 5.0) were presented as n (%). The primary endpoint was investigator-evaluated overall survival (OS). As this is a retrospective cohort study, sample size calculation was not performed. Eligible patients would be enrolled as many as possible. Results: A total of 90 patients were enrolled, including 58 patients who received TAS-102 plus BEV and another 32 patients who received TAS-102 monotherapy. The known baseline characteristics were comparable (P<0.05). With a median follow-up of 4.60 months (range, 0.20-22.80), the median OS (mOS) time in the TAS-102 plus BEV group was longer than that in the TAS-102 monotherapy group (10.83 vs. 7.43 months), but the difference was not significant (P=0.79). The median progression-free survival (mPFS) time was comparable between the two groups (4.67 vs. 4.30 months, P=0.96). Multivariate Cox regression analysis demonstrated that undergoing therapy after TAS-102 either with or without BEV was an independent risk factor for OS [hazard ratio (HR) =0.25; 95% confidence interval (CI): 0.09-0.71, P<0.01], and previous treatment with cetuximab was an independent protective factor for PFS (HR =0.17; 95% CI: 0.03-0.91, P=0.04). Of the 70 patients who were evaluated, those receiving TAS-102 plus BEV showed trend of a higher objective response rate (ORR) and disease control rate (DCR) than those who received TAS-102 monotherapy (P=0.16 and P=0.29, respectively). Adverse events (AEs) were similar between the two groups, except that the incidence of platelet count decrease (grade ≥3) was significantly higher in the TAS-102 plus BEV group. Conclusions: There was a trend in favor of the combination of BEV plus TAS-102 regarding OS and DCR, without reaching statistical significance, and it means that there was no clear advantage of one over the other in terms of efficacy. Further prospective studies are still necessary to draw a definite conclusion.

7.
IEEE Trans Cybern ; 52(6): 5026-5039, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33151887

RESUMEN

Rank minimization is widely used to extract low-dimensional subspaces. As a convex relaxation of the rank minimization, the problem of nuclear norm minimization has been attracting widespread attention. However, the standard nuclear norm minimization usually results in overcompression of data in all subspaces and eliminates the discrimination information between different categories of data. To overcome these drawbacks, in this article, we introduce the label information into the nuclear norm minimization problem and propose a labeled-robust principal component analysis (L-RPCA) to realize nuclear norm minimization on multisubspace data. Compared with the standard nuclear norm minimization, our method can effectively utilize the discriminant information in multisubspace rank minimization and avoid excessive elimination of local information and multisubspace characteristics of the data. Then, an effective labeled-robust regression (L-RR) method is proposed to simultaneously recover the data and labels of the observed data. Experiments on real datasets show that our proposed methods are superior to other state-of-the-art methods.


Asunto(s)
Algoritmos , Análisis de Componente Principal
8.
Ann Transl Med ; 10(16): 880, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36111036

RESUMEN

Background: Managements for refractory proficient mismatch repair (pMMR) or microsatellite stable (MSS) metastatic colorectal cancer (mCRC) were still challenging and controversial. Our study sought to investigate the efficacy and safety of anti-programmed cell death protein 1 (anti-PD-1) antibodies plus regorafenib in refractory pMMR/MSS mCRC. Methods: We retrospectively analyzed the efficacy and safety of 103 pMMR/MSS mCRC patients treated with at least one dose of anti-PD-1 antibodies plus regorafenib (80 mg once daily for 21 days on/7 days off 28 days as a cycle) between July 2019 and June 2021 at the Hunan Cancer Hospital. All patients had previously received at least second-line treatment. The patients were evaluated by computed tomography every 2 or 3 treatment cycles until progression or being lost to follow-up. The primary end point was overall survival (OS). Results: The median follow-up period was 5.30 (range, 0.50-22.50) months. The median OS (mOS) and medical progression-free survival (mPFS) were 8.40 and 2.50 months for the entire cohort, respectively. The mOS and mPFS were 16.07 and 3.10 months in patients who received >1 cycle of anti-PD-1 antibodies and regorafenib (n=55), which were significantly longer than 4.37 and 1.11 months in those received only 1 cycle (n=48) (both P<0.001, respectively). The Cox multivariate regression analysis demonstrated that the number of cycles of regorafenib plus PD-1 and previously undergone surgery were independent risk factors for OS, whereas Sintilimab was confirmed to have a significant better PFS compared to other anti-PD-1 antibodies. Of the 55 patients who were evaluated, 7 were diagnosed with a partial response (PR) and another 16 were diagnosed with stable disease (SD), but no patient showed a complete response (CR). Thus, the objective response rate (ORR) was 12.7% and the disease control rate was 41.8%. Treatment-related adverse events (TRAEs) of grade 3 or higher occurred in 13 (12.6%) patients. Conclusions: The combination of regorafenib plus anti-PD-1 antibodies has a manageable safety profile and may improve prognosis for pMMR/MSS mCRC patients, especially those who received >1 cycle. Compared to the other anti-PD-1 antibodies, sintilimab may be more efficacious; however, further prospective studies need to be conducted to confirm our findings.

9.
Kaohsiung J Med Sci ; 37(8): 709-717, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34003591

RESUMEN

This work investigated the effect of α-mangostin (α-M) on gastric cancer (GC) cell chemoresistance and its underlying mechanisms. Different concentrations of α-M and CDDP were applied to treat GC cells (SGC7901) and CDDP-resistant GC cells (SGC7901/CDDP) for 24 or 48 h. CCK-8 assays were used to measure the inhibitory effect of CDDP or α-M on SGC7901 and SGC7901/CDDP cells as well as the half-maximal inhibitory concentrations (IC50) of α-M for SGC7901 and SGC7901/CDDP cells. The optimal concentration and induction time of CDDP or α-M were determined. SGC7901/CDDP cells were treated with CDDP or/and α-M, where some of them were transfected with pcDNA3.1 or pcDNA3.1-EBI3. Cell proliferation and apoptosis were assessed as well as the levels of EBI3, STAT3, p-STAT3, autophagy-related proteins, and apoptosis-related proteins. CDDP inhibited SGC7901 cell proliferation in a dose-dependent manner. The IC50 of α-M for SGC7901 cells was 12.86 µM and that for SGC7901/CDDP cells was 13.69 µM. The optimal concentrations of CDDP and α-M for SGC7901/CDDP cells were 2 and 15 µM, respectively, and the optimal time was 48 h. The SGC7901/CDDP cells in the CDDP+/α-M+ group had elevated inhibition of proliferation and apoptosis rates. Western blot analysis revealed enhanced levels of LC3-II/I and Beclin1, reduced p62 level, decreased Bcl2 level, and increased levels of Bax and cleaved caspase-3/9. The EBI3/STAT3 pathway was implicated in the effect of α-M on SGC7901/CDDP cell development. α-M increases the chemosensitivity of GC cells by facilitating autophagy and inactivating the EBI3/STAT3 pathway.


Asunto(s)
Antineoplásicos/uso terapéutico , Cisplatino/uso terapéutico , Resistencia a Antineoplásicos/efectos de los fármacos , Neoplasias Gástricas/tratamiento farmacológico , Xantonas/farmacología , Antineoplásicos/farmacología , Autofagia/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cisplatino/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Interleucinas/metabolismo , Antígenos de Histocompatibilidad Menor/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/efectos de los fármacos , Neoplasias Gástricas/patología
10.
Pest Manag Sci ; 76(8): 2627-2634, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32096312

RESUMEN

BACKGROUND: The safety of fungal insecticides to apiculture is a public concern but remains poorly understood. This study seeks to evaluate whether, how and why wide-spectrum Beauveria bassiana insecticides are safe to honey bees in a novel assessment system. RESULTS: Mesonotum dipping with a 108 conidia ml-1 suspension and body contact with conidial suspension in sucrose solution caused high mortalities of adult forager bees at 25 °C optimal for conidial germination and hyphal invasion. Intriguingly, colony sizes in the hives contaminated by the forager bees contacting viable and inactivated conidia at two sites (1.2 km in distance), respectively, showed similar increase percentages (31.7% versus 29.2%) during a 4-week summer period of exposure to environment. No sign of fungal infection was found within each of the monitored colonies. Neither was fungal outgrowth observed on surfaces of bee cadavers cleaned from each hive at either site. Hourly counts of cleaned cadavers from videotapes presented no significant difference in colony-cleaning behavior between the two sites. During the period, in-hive temperatures at both sites were persistently stabilized at approximately 35 °C, which abolished conidial germination and were far above the out-hive temperature range. CONCLUSION: It is colony heating that protects honey bee populations from a risk of forager bees' contact with formulated conidia applied for arthropod pest control. No role was detected for colony self-cleaning behavior in protecting the bee colonies from the risk. © 2020 Society of Chemical Industry.


Asunto(s)
Beauveria , Animales , Abejas , Calefacción , Insecticidas , Estaciones del Año , Esporas Fúngicas
11.
Talanta ; 73(4): 644-50, 2007 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-19073083

RESUMEN

By optimizing the extraction, separation and analytical conditions, a simple, reliable and effective high-performance liquid chromatography method coupled with photodiode array detector (HPLC-DAD) is presented for simultaneous determination of nine aristolochic acid (AA) analogues, i.e., AA I, AA II, AA C, AA D, 7-OH AA I, aristolic acid, AL II, AL III and AL IV, in twelve medicinal herbs and two preparations. The separation was completed on a C18 column with aqueous methanol containing 0.2% (V/V) acetic acid as mobile phase. Linearities of around two orders of magnitude were obtained with correlation coefficients exceeding 0.9950. Satisfactory intra-day and inter-day precisions were achieved with R.S.D.s less than 4.35%, and the average recovery factors obtained were in the range of 88.4-98.8%. The proposed method appears to be suitable for use as a tool for safety assurance and quality control for commercially available suspect samples containing aristolochic acid analogues.

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