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1.
Br J Clin Pharmacol ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39160062

RESUMEN

AIMS: Osimertinib is a third-generation, irreversible, central nervous system-active, epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) with efficacy in EGFR-mutated non-small cell lung cancer (NSCLC). We assessed the relationship between plasma osimertinib levels and its efficacy and safety events. METHODS: Comprehensive pharmacokinetics exposure-response (E-R) modelling was performed utilizing steady state area under the curve (AUCss) data from first-line, ≥second-line and adjuvant studies from the osimertinib clinical development programme (20-240 mg once-daily dosing; N = 1689 patients). Analyses were conducted for survival using a proportional hazard model; for interstitial lung disease (ILD) and left ventricular ejection fraction (LVEF) events using a penalized logistic regression model and graphical analysis of potential confounding factors; and for rash and diarrhoea events using descriptive analysis. RESULTS: E-R modelling analyses indicated no clear trend of increasing efficacy with increasing osimertinib AUCss; efficacy in all exposure quartiles was significantly better than the control arm (comparator EGFR-TKI, chemotherapy or placebo) irrespective of treatment line. Model-based analysis suggested a potential relationship between increased osimertinib exposure and increased probability of ILD events, predominantly in Japanese patients. Additionally, there were increased probabilities of rash or diarrhoea with increasing osimertinib exposure. The probability of LVEF events showed overlapping confidence intervals for osimertinib ≤80 mg and control. CONCLUSIONS: E-R modelling in patients with EGFR-mutated NSCLC demonstrated that increased osimertinib exposure was unlikely to increase efficacy but may increase occurrence of certain adverse events. Hence, long-term treatment with doses ≥80 mg was not expected to provide additional benefit.

2.
Eur J Med Chem ; 277: 116773, 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-39163779

RESUMEN

Due to the emerging global epidemic of obesity, developing safe and effective agents for anti-obesity is urgently needed. Our previous study found that 2-pyrimidinylindole derivative Wd3d exhibited potential anti-obesity activity. Herein, to further optimize the potential moiety, structural modifications were proceeded for two rounds in this study. Firstly, we designed, synthesized, and evaluated 36 new derivatives of 2-pyrimidinylindole scaffold with different substituents on the indole ring and pyrimidine ring to investigate their structure-activity relationship (SAR). Then, analogs with potent activity had the aldehyde group replaced with the acylhydrazone group to reduce cytotoxicity and improve metabolic stability. Detailed SAR studies and animal evaluation experiments led to the discovery of the compound 9ga, which significantly reduced TG accumulation with an EC50 value of 0.07 µM and showed relatively low cytotoxicity with an IC50 value of around 24 µM. Oral administration of 9ga effectively prevented the excessive growth of body weight and lessened fat mass as well as liver mass, decreased lipid accumulation in the liver and blood, and improved the heart injury parameter in the diet-induced obesity mouse model significantly better than Wd3d. A mechanism study showed that 9ga regulated the lipid metabolism during early adipogenesis by inhibiting PPARγ pathway. In conclusion, our study further highlights the anti-obesity potential of 2-pyrimidinylindole derivatives in diet-induced obesity.


Asunto(s)
Fármacos Antiobesidad , Diseño de Fármacos , Indoles , Obesidad , Relación Estructura-Actividad , Animales , Fármacos Antiobesidad/farmacología , Fármacos Antiobesidad/síntesis química , Fármacos Antiobesidad/química , Ratones , Indoles/química , Indoles/farmacología , Indoles/síntesis química , Obesidad/tratamiento farmacológico , Administración Oral , Estructura Molecular , Masculino , Pirimidinas/química , Pirimidinas/farmacología , Pirimidinas/síntesis química , Relación Dosis-Respuesta a Droga , Ratones Endogámicos C57BL , Humanos , Células 3T3-L1
3.
BMC Cancer ; 24(1): 965, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39107701

RESUMEN

PURPOSE: This study explores integrating clinical features with radiomic and dosiomic characteristics into AI models to enhance the prediction accuracy of radiation dermatitis (RD) in breast cancer patients undergoing volumetric modulated arc therapy (VMAT). MATERIALS AND METHODS: This study involved a retrospective analysis of 120 breast cancer patients treated with VMAT at Kaohsiung Veterans General Hospital from 2018 to 2023. Patient data included CT images, radiation doses, Dose-Volume Histogram (DVH) data, and clinical information. Using a Treatment Planning System (TPS), we segmented CT images into Regions of Interest (ROIs) to extract radiomic and dosiomic features, focusing on intensity, shape, texture, and dose distribution characteristics. Features significantly associated with the development of RD were identified using ANOVA and LASSO regression (p-value < 0.05). These features were then employed to train and evaluate Logistic Regression (LR) and Random Forest (RF) models, using tenfold cross-validation to ensure robust assessment of model efficacy. RESULTS: In this study, 102 out of 120 VMAT-treated breast cancer patients were included in the detailed analysis. Thirty-two percent of these patients developed Grade 2+ RD. Age and BMI were identified as significant clinical predictors. Through feature selection, we narrowed down the vast pool of radiomic and dosiomic data to 689 features, distributed across 10 feature subsets for model construction. In the LR model, the J subset, comprising DVH, Radiomics, and Dosiomics features, demonstrated the highest predictive performance with an AUC of 0.82. The RF model showed that subset I, which includes clinical, radiomic, and dosiomic features, achieved the best predictive accuracy with an AUC of 0.83. These results emphasize that integrating radiomic and dosiomic features significantly enhances the prediction of Grade 2+ RD. CONCLUSION: Integrating clinical, radiomic, and dosiomic characteristics into AI models significantly improves the prediction of Grade 2+ RD risk in breast cancer patients post-VMAT. The RF model analysis demonstrates that a comprehensive feature set maximizes predictive efficacy, marking a promising step towards utilizing AI in radiation therapy risk assessment and enhancing patient care outcomes.


Asunto(s)
Neoplasias de la Mama , Radiodermatitis , Radioterapia de Intensidad Modulada , Humanos , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/diagnóstico por imagen , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Radiodermatitis/etiología , Radiodermatitis/diagnóstico por imagen , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Anciano , Adulto , Planificación de la Radioterapia Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Dosificación Radioterapéutica , Inteligencia Artificial , Radiómica
4.
Proc Natl Acad Sci U S A ; 121(29): e2307726121, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38976735

RESUMEN

Watching movies is among the most popular entertainment and cultural activities. How do viewers react when a movie sequel increases racial minority actors in the main cast ("minority increase")? On the one hand, such sequels may receive better evaluations if viewers appreciate racially inclusive casting for its novel elements (the value-in-diversity perspective) and moral appeal (the fairness perspective on diversity). On the other hand, discrimination research suggests that if viewers harbor biases against racial minorities, sequels with minority increase may receive worse evaluations. To examine these competing possibilities, we analyze a unique panel dataset of movie series released from 1998 to 2021 and conduct text analysis of 312,457 reviews of these movies. Consistent with discrimination research, we find that movies with minority increase receive lower ratings and more toxic reviews. Importantly, these effects weaken after the advent of the Black Lives Matter (BLM) movement, especially when the movement's intensity is high. These results are reliable across various robustness checks (e.g., propensity score matching, random implementation test). We conceptually replicate the bias mitigation effect of BLM in a preregistered experiment: Heightening the salience of BLM increases White individuals' acceptance of racial minority increase in a movie sequel. This research demonstrates the power of social movements in fostering diversity, equality, and inclusion.


Asunto(s)
Películas Cinematográficas , Racismo , Humanos , Racismo/psicología , Minorías Étnicas y Raciales , Negro o Afroamericano/psicología , Diversidad Cultural , Grupos Minoritarios/psicología
5.
J Med Chem ; 67(14): 12439-12458, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38996004

RESUMEN

The discovery of effective and safe antiobesity agents remains a challenging yet promising field. Our previous studies identified Bouchardatine derivatives as potential antiobesity agents. However, the 8a-aldehyde moiety rendered them unsuitable for drug development. In this study, we designed two series of novel derivatives to modify this structural feature. Through a structure-activity relationship study, we elucidated the role of the 8a-aldehyde group in toxicity induction. We identified compound 14d, featuring an 8a-N-acylhydrazone moiety, which exhibited significant lipid-lowering activity and reduced toxicity. Compound 14d shares a similar lipid-lowering mechanism with our lead compound 3, but demonstrates improved pharmacokinetic properties and safety profile. Both oral and injectable administration of 14d significantly reduced body weight gain and ameliorated metabolic syndrome in diet-induced obese mice. Our findings identify 14d as a promising antiobesity agent and highlight the potential of substituting the aldehyde group with an N-acylhydrazone to enhance drug-like properties.


Asunto(s)
Aldehídos , Fármacos Antiobesidad , Hidrazonas , Obesidad , Animales , Fármacos Antiobesidad/farmacología , Fármacos Antiobesidad/síntesis química , Fármacos Antiobesidad/farmacocinética , Fármacos Antiobesidad/uso terapéutico , Fármacos Antiobesidad/química , Hidrazonas/farmacología , Hidrazonas/química , Hidrazonas/síntesis química , Hidrazonas/farmacocinética , Hidrazonas/uso terapéutico , Ratones , Relación Estructura-Actividad , Aldehídos/química , Masculino , Obesidad/tratamiento farmacológico , Ratones Endogámicos C57BL , Dieta Alta en Grasa/efectos adversos , Humanos , Ratones Obesos , Estructura Molecular
7.
Orphanet J Rare Dis ; 19(1): 238, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38879497

RESUMEN

BACKGROUND: Biallelic pathogenic variants in USH2A lead to Usher syndrome or non-syndromic retinitis pigmentosa, and shown to have geographical and ethnical distribution in previous studies. This study provided a deeper understanding of the detailed clinical features using multimodal imaging, genetic spectrum, and genotype-phenotype correlations of USH2A-related retinal dystrophies in Taiwan. RESULTS: In our cohort, the mean age at first visit was 47.66 ± 13.54 years, and the mean age at symptom onset, which was referred to the onset of nyctalopia and/or visual field constriction, was 31.21 ± 15.24 years. Among the variants identified, 23 (50%) were missense, 10 (22%) were splicing variants, 8 (17%) were nonsense, and 5 (11%) were frameshift mutations. The most predominant variant was c.2802T>G, which accounted for 21% of patients, and was located in exon 13. Patients with truncated alleles had significantly earlier symptom onset and seemly poorer disease progression regarding visual acuity, ellipsoid zone line length, and hypofluorescent lesions in the macula than those who had the complete gene. However, the clinical presentation revealed similar progression between patients with and without the c.2802T>G variant. During long-term follow-up, the patients had different ellipsoid zone line progression rates and were almost evenly distributed in the fast, moderate, and slow progression subgroups. Although a younger onset age and a smaller baseline intact macular area was observed in the fast progression subgroup, the results showed no significant difference. CONCLUSIONS: This is the first cohort study to provide detailed genetic and longitudinal clinical analyses of patients with USH2A-related retinal dystrophies in Taiwan. The mutated allele frequency in exon 13 was high in Taiwan due to the predominant c.2802T>G variant. Moreover, truncated variants greatly impacted disease progression and determined the length of therapeutic windows. These findings provide insight into the characteristics of candidates for future gene therapies.


Asunto(s)
Exones , Proteínas de la Matriz Extracelular , Distrofias Retinianas , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Exones/genética , Proteínas de la Matriz Extracelular/genética , Prevalencia , Distrofias Retinianas/genética , Distrofias Retinianas/patología , Taiwán , Síndromes de Usher/genética
8.
J Imaging ; 10(4)2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38667976

RESUMEN

Taiwan, frequently affected by extreme weather causing phenomena such as earthquakes and typhoons, faces a high incidence of rockfall disasters due to its largely mountainous terrain. These disasters have led to numerous casualties, government compensation cases, and significant transportation safety impacts. According to the National Science and Technology Center for Disaster Reduction records from 2010 to 2022, 421 out of 866 soil and rock disasters occurred in eastern Taiwan, causing traffic disruptions due to rockfalls. Since traditional sensors of disaster detectors only record changes after a rockfall, there is no system in place to detect rockfalls as they occur. To combat this, a rockfall detection and tracking system using deep learning and image processing technology was developed. This system includes a real-time image tracking and recognition system that integrates YOLO and image processing technology. It was trained on a self-collected dataset of 2490 high-resolution RGB images. The system's performance was evaluated on 30 videos featuring various rockfall scenarios. It achieved a mean Average Precision (mAP50) of 0.845 and mAP50-95 of 0.41, with a processing time of 125 ms. Tested on advanced hardware, the system proves effective in quickly tracking and identifying hazardous rockfalls, offering a significant advancement in disaster management and prevention.

10.
EClinicalMedicine ; 66: 102308, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38045802

RESUMEN

Background: Zuranolone is recognised as a promising antidepressant agent. Our study aimed to investigate the efficacy and safety of zuranolone in treating major depressive disorder (MDD). Methods: A systematic review was conducted by searching major databases from inception to August 20, 2023 (INPLASY: 202360087). A meta-analysis was performed by using a random-effects model to calculate effect sizes, expressed as standardised mean differences (SMDs) and odds ratios (ORs) with 95% confidence intervals (CIs). The primary outcome was improvement in depressive symptoms, while secondary outcomes included response and remission rates of depression, improvement in anxiety symptoms, incidence of dropouts, and any side effects. We conducted subgroup analyses for general MDD and postpartum-onset MDD and a dose-response meta-analysis to estimate the relationship between zuranolone dose and outcomes. Findings: The study included seven randomised control trials involving 1789 patients. Zuranolone reduced depressive symptoms (SMD = -0.37, 95% CIs = -0.51 to -0.23), increased response rate (OR = 2.06, 95% CIs = 1.48-2.85) and remission rate (OR = 2.04, 95% CIs = 1.38-3.02), and reduced anxiety symptoms (SMD = -0.26, 95% CIs = -0.39 to -0.14). Furthermore, zuranolone-treated patients experienced more side effects than those in the control group (OR = 1.40, 95% CIs = 1.10-1.78), although dropout rate did not significantly differ between the two groups (OR = 1.13, 95% CIs = 0.85-1.49). According to the dose-response meta-analysis, zuranolone could effectively improve depression and anxiety at increasing doses up to a maximum daily dose of 30 mg; however, side effects increased with doses exceeding 30 mg. Based on subgroup analyses, zuranolone showed greater efficacy in treatment of postpartum-onset MDD than general MDD, but the difference did not reach statistical significance. Interpretation: Our findings suggested that zuranolone is effective in alleviating depression and anxiety. Nevertheless, there is a potential risk of adverse effects. Given its therapeutic efficacy and risk of side effects, a daily dose of 30 mg appears to be the optimal choice. Funding: Chang Gung Medical Foundation.

11.
J Biol Chem ; 299(11): 105335, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37827291

RESUMEN

Hepatoma-derived growth factor (HDGF) overexpression and uncontrolled reactive oxygen species (ROS) accumulation are involved in malignant transformation and poor prognosis in various types of cancer. However, the interplay between HDGF and ROS generation has not been elucidated in hepatocellular carcinoma. Here, we first analyzed the profile of HDGF expression and ROS production in newly generated orthotopic hepatomas by ultrasound-guided implantation. In situ superoxide detection showed that HDGF-overexpressing hepatomas had significantly elevated ROS levels compared with adjacent nontumor tissues. Consistently, liver tissues from HDGF-deficient mice exhibited lower ROS fluorescence than those from age- and sex-matched WT mice. ROS-detecting fluorescent dyes and flow cytometry revealed that recombinant HDGF (rHDGF) stimulated the production of superoxide anion, hydrogen peroxide, and mitochondrial ROS generation in cultured hepatoma cells in a dose-dependent manner. In contrast, the inactive Ser103Ala rHDGF mutant failed to promote ROS generation or oncogenic behaviors. Seahorse metabolic flux assays revealed that rHDGF dose dependently upregulated bioenergetics through enhanced basal and total oxygen consumption rate, extracellular acidification rate, and oxidative phosphorylation in hepatoma cells. Moreover, antioxidants of N-acetyl cysteine and MitoQ treatment significantly inhibited HDGF-mediated cell proliferation and invasive capacity. Genetic silencing of superoxide dismutase 2 augmented the HDGF-induced ROS generation and oncogenic behaviors of hepatoma cells. Finally, genetic knockdown nucleolin (NCL) and antibody neutralization of surface NCL, the HDGF receptor, abolished the HDGF-induced increase in ROS and mitochondrial energetics. In conclusion, this study has demonstrated for the first time that the HDGF/NCL signaling axis induces ROS generation by elevating ROS generation in mitochondria, thereby stimulating liver carcinogenesis.


Asunto(s)
Carcinoma Hepatocelular , Animales , Ratones , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Especies Reactivas de Oxígeno , Carcinogénesis/genética
12.
Comput Struct Biotechnol J ; 21: 4030-4043, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37664175

RESUMEN

Esophageal squamous cell carcinoma (ESCC), one of the most lethal cancers, has become a global health issue. Stearoyl-coA desaturase 1 (SCD1) has been demonstrated to play a crucial role in human cancers. However, pan-cancer analysis has revealed little evidence to date. In the current study, we systematically inspected the expression patterns and potential clinical outcomes of SCD1 in multiple human cancers. SCD1 was dysregulated in several types of cancers, and its aberrant expression acted as a diagnostic biomarker, indicating that SCD1 may play a role in tumorigenesis. We used ESCC as an example to demonstrate that SCD1 was dramatically upregulated in tumor tissues of ESCC and was associated with clinicopathological characteristics in ESCC patients. Furthermore, Kaplan-Meier analysis showed that high SCD1 expression was correlated with poor progression-free survival (PFS) and disease-free survival (DFS) in ESCC patients. The protein-protein interaction (PPI) network and module analysis by PINA database and Gephi were performed to identify the hub targets. Meanwhile, the functional annotation analysis of these hubs was constructed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Functionally, the gain-of-function of SCD1 in ESCC cells promoted cell proliferation, migration, and invasion; in contrast, loss-of-function of SCD1 in ESCC cells had opposite effects. Bioinformatic, QPCR, Western blotting and luciferase assays indicated that SCD1 was a direct target of miR-181a-5p in ESCC cells. In addition, gain-of-function of miR-181a-5p in ESCC cells reduced the cell growth, migratory, and invasive abilities. Conversely, inhibition of miR-181a-5p expression by its inhibitor in ESCC cells had opposite biological effects. Importantly, reinforced SCD1 in miR-181a-5p mimic ESCC transfectants reversed miR-181a-5p mimic-prevented malignant phenotypes of ESCC cells. Taken together, these results indicate that SCD1 expression influences tumor progression in a variety of cancers, and the miR-181a-5p/SCD1 axis may be a potential therapeutic target for ESCC treatment.

13.
ACS Nano ; 17(19): 19033-19051, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37737568

RESUMEN

Selective autophagy is a defense mechanism by which foreign pathogens and abnormal substances are processed to maintain cellular homeostasis. Sequestosome 1 (SQSTM1)/p62, a vital selective autophagy receptor, recruits ubiquitinated cargo to form autophagosomes for lysosomal degradation. Nab-PTX is an albumin-bound paclitaxel nanoparticle used in clinical cancer therapy. However, the role of SQSTM1 in regulating the delivery and efficacy of nanodrugs remains unclear. Here we showed that SQSTM1 plays a crucial role in Nab-PTX drug delivery and efficacy in human lung and colorectal cancers. Nab-PTX induces SQSTM1 phosphorylation at Ser403, which facilitates its incorporation into the selective autophagy of nanoparticles, known as nanoparticulophagy. Nab-PTX increased LC3-II protein expression, which triggered autophagosome formation. SQSTM1 enhanced Nab-PTX recognition to form autophagosomes, which were delivered to lysosomes for albumin degradation, thereby releasing PTX to induce mitotic catastrophe and apoptosis. Knockout of SQSTM1 downregulated Nab-PTX-induced mitotic catastrophe, apoptosis, and tumor inhibition in vitro and in vivo and inhibited Nab-PTX-induced caspase 3 activation via a p53-independent pathway. Ectopic expression of SQSTM1 by transfection of an SQSTM1-GFP vector restored the drug efficacy of Nab-PTX. Importantly, SQSTM1 is highly expressed in advanced lung and colorectal tumors and is associated with poor overall survival in clinical patients. Targeting SQSTM1 may provide an important strategy to improve nanodrug efficacy in clinical cancer therapy. This study demonstrates the enhanced efficacy of Nab-PTX for human lung and colorectal cancers via SQSTM1-mediated nanodrug delivery.

14.
Eur J Med Chem ; 260: 115729, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37607439

RESUMEN

Obesity, a global pandemic posing a growing threat to human health, necessitates the development of effective and safe anti-obesity agents. Our previous studies highlighted the lipid-lowering effects of indolylquinazoline Bouchardatine and its derivatives. In this study, we employed scaffold hopping and simplification strategies to design and synthesize two new series derivatives by modifying the D ring. Extensive discussions have been conducted regarding the structure-activity relationship between lipid-lowering activity and the new compounds. These discussions have resulted in the discovery of 2-pyrimidinylindole derivatives as a promising scaffold for anti-obesity treatment. The new 2-pyrimidinylindole derivatives exhibited comparable lipid-lowering activity to the previously reported indolylquinazoline derivatives, including SYSU-3d and R17, with reduced toxicity. The most potent compound, 5a, demonstrated a larger therapeutic index, improved aqueous solubility and oral bioavailability compared to the previous lead compounds. In vivo evaluation indicated that 5a effectively reduced lipid accumulation in adipose tissue, improved glucose tolerance, and mitigated insulin resistance and liver function damage caused by a high-fat and high-cholesterol diet. Mechanism studies indicated that 5a may regulate lipid metabolism through the modulation of the PPARγ signaling pathway. Overall, our study has identified a highly active compound 5a, and provided the basis for further development of 2-pyrimidinylindole as a promising scaffold for obesity treatment.


Asunto(s)
Fármacos Antiobesidad , Hipercolesterolemia , Humanos , Metabolismo de los Lípidos , Fármacos Antiobesidad/farmacología , Disponibilidad Biológica , Obesidad/tratamiento farmacológico , Lípidos
15.
Int J Antimicrob Agents ; 62(3): 106902, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37380093

RESUMEN

OBJECTIVES: Antimicrobial resistance is a major global threat. Because of the stagnant antibiotic pipeline, synergistic antibiotic combination therapy has been proposed to treat rapidly emerging multidrug-resistant (MDR) pathogens. We investigated antimicrobial synergy of polymyxin/rifampicin combination against MDR Acinetobacter baumannii. METHODS: In vitro static time-kill studies were performed over 48 h at an initial inoculum of ∼107 CFU/mL against three polymyxin-susceptible but MDR A. baumannii isolates. Membrane integrity was examined at 1 and 4 h post-treatment to elucidate the mechanism of synergy. Finally, a semi-mechanistic PK/PD model was developed to simultaneously describe the time course of bacterial killing and prevention of regrowth by mono- and combination therapies. RESULTS: Polymyxin B and rifampicin alone produced initial killing against MDR A. baumannii but were associated with extensive regrowth. Notably, the combination showed synergistic killing across all three A. baumannii isolates with bacterial loads below the limit of quantification for up to 48 h. Membrane integrity assays confirmed the role of polymyxin-driven outer membrane remodelling in the observed synergy. Subsequently, the mechanism of synergy was incorporated into a PK/PD model to describe the enhanced uptake of rifampicin due to polymyxin-induced membrane permeabilisation. Simulations with clinically utilised dosing regimens confirmed the therapeutic potential of this combination, particularly in the prevention of bacterial regrowth. Finally, results from a neutropenic mouse thigh infection model confirmed the in vivo synergistic killing of the combination against A. baumannii AB5075. CONCLUSION: Our results showed that polymyxin B combined with rifampicin is a promising option to treat bloodstream and tissue infection caused by MDR A. baumannii and warrants clinical evaluations.


Asunto(s)
Acinetobacter baumannii , Polimixina B , Animales , Ratones , Polimixina B/farmacología , Rifampin/farmacología , Polimixinas/farmacología , Sinergismo Farmacológico , Farmacorresistencia Bacteriana Múltiple , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología
16.
Polymers (Basel) ; 15(11)2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37299263

RESUMEN

Camptothecin (CPT) has been shown to exhibit anticancer activity against several cancers. Nevertheless, CPT is very hydrophobic with poor stability, and thus its medical application is limited. Therefore, various drug carriers have been exploited for effectively delivering CPT to the targeted cancer site. In this study, a dual pH/thermo-responsive block copolymer of poly(acrylic acid-b-N-isopropylacrylamide) (PAA-b-PNP) was synthesized and applied to encapsulate CPT. At temperatures above its cloud point, the block copolymer self-assembled to form nanoparticles (NPs) and in situ encapsulate CPT, owing to their hydrophobic interaction as evidenced by fluorescence spectrometry. Chitosan (CS) was further applied on the surface through the formation of a polyelectrolyte complex with PAA for improving biocompatibility. The average particle size and zeta potential of the developed PAA-b-PNP/CPT/CS NPs in a buffer solution were 168 nm and -30.6 mV, respectively. These NPs were still stable at least for 1 month. The PAA-b-PNP/CS NPs exhibited good biocompatibility toward NIH 3T3 cells. Moreover, they could protect the CPT at pH 2.0 with a very slow-release rate. At pH 6.0, these NPs could be internalized by Caco-2 cells, followed by intracellular release of the CPT. They became highly swollen at pH 7.4, and the released CPT was able to diffuse into the cells at higher intensity. Among several cancer cell lines, the highest cytotoxicity was observed for H460 cells. As a result, these environmentally-responsive NPs have the potential to be applied in oral administration.

17.
Molecules ; 28(6)2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36985661

RESUMEN

Mitochondria have a crucial role in regulating energy metabolism and their dysfunction has been linked to tumorigenesis. Cancer diagnosis and intervention have a great interest in the development of new agents that target biomolecules within mitochondria. However, monitoring and modulating mitochondria RNA (mtRNA), an essential component in mitochondria, in cells is challenging due to limited functional research and the absence of targeting agents. In this study, we designed and synthesized a fluorescent quinolinium derivative, QUCO-1, which actively lit up with mtRNA in both normal and cancer cells in vitro. Additionally, we evaluated the function of QUCO-1 as an mtRNA ligand and found that it effectively induced severe mitochondrial dysfunction and OXPHOS inhibition in RKO colorectal cancer cells. Treatment with QUCO-1 resulted in apoptosis, cell cycle blockage at the G2/M phase, and the effective inhibition of cell proliferation. Our findings suggest that QUCO-1 has great potential as a promising probe and therapeutic agent for mtRNA, with the potential for treating colorectal cancer.


Asunto(s)
Neoplasias Colorrectales , Mitocondrias , Humanos , ARN Mitocondrial/metabolismo , Mitocondrias/metabolismo , Proliferación Celular , Apoptosis , Colorantes Fluorescentes/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Línea Celular Tumoral
18.
Clin Microbiol Infect ; 29(6): 702-709, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36736661

RESUMEN

BACKGROUND: The increasing emergence of antimicrobial resistance worldwide has led to renewed interest in phage therapy. Unlike antibiotics, the lack of pharmacokinetics/pharmacodynamics (PK/PD) information represents a major challenge for phage therapy. As therapeutic phages are biological entities with the ability to self-replicate in the presence of susceptible bacteria, their PK/PD is far more complicated than that of antibiotics. OBJECTIVES: This narrative review examines the current literature on phage pharmacology and highlights major pharmacological challenges for phage therapy. SOURCES: Included articles were identified by searching PubMed and Google Scholar till June 2022. The search terms were 'bacteriophage', 'antimicrobial', 'pharmacokinetics' and 'pharmacodynamics'. Additional relevant references were obtained from articles retrieved from the primary search. CONTENT: In this review, phage PK is first discussed, focusing on absorption, distribution, metabolism, and elimination. Key factors affecting phage antimicrobial activities are reviewed, including multiplicity of infection, passive and active phage therapy, and the involvement of the human immune system. Importantly, we emphasize the impact of phage self-replication on the PK/PD and the fundamental phage characteristics that are required for PK/PD modelling and clinical translation. IMPLICATIONS: Recent progress in phage pharmacology has shown that we are in a far better position now to treat infections with phage therapy than a century ago. However, phage therapy is still in its infancy when compared to antibiotics due to the scarce pharmacological knowledge (e.g. PK/PD). Optimization of phage PK/PD is key for translation of phage therapy in patients.


Asunto(s)
Antiinfecciosos , Bacteriófagos , Terapia de Fagos , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antiinfecciosos/farmacología , Bacterias
19.
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