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1.
Mol Biol Rep ; 51(1): 124, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38227097

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is a global health problem. The gut microbiome is now recognized as an important underlying factor to the initiation and progression of CRC. Fusobacterium nucleatum (FN) is one of the most studied bacteria in the aetiology of CRC. This study provided cohort evidence on the association of FN infection with clinicopathologic features in CRC patients. METHODS: We analysed the cancerous and adjacent non-cancerous formalin-fixed paraffin embedded (FFPE) tissue of 83 CRC patients from a single medical centre in Malaysia. TaqMan probe-based qPCR targeting the 16S rRNA gene was used to detect the presence of FN in the extracted FFPE DNA. The differences in FN expression between cancer and non-cancer tissues were evaluated. Association studies between FN infection in the tumour and relative FN abundance with available clinical data were conducted. RESULTS: FN was more abundant in the cancerous tissue compared to non-cancerous tissue (p = 0.0025). FN infection in the tumour was significantly associated with lymph node metastasis (p = 0.047) and cancer staging (p = 0.032), but not with other clinicopathologic variables. In double-positive patients where FN was detected in both cancerous and non-cancerous tissue, the expression fold-change of FN, calculated using 2-ΔΔCT formula, was significantly higher in patients with tumour size equal to or greater than 5 cm (p = 0.033) and in KRAS-mutated patients (p = 0.046). CONCLUSIONS: FN is enriched in CRC tumour tissue and is associated with tumour size, lymph node metastasis, cancer staging, and KRAS mutation in this single-centre small cohort study.


Asunto(s)
Neoplasias Colorrectales , Fusobacterium nucleatum , Humanos , Estudios de Cohortes , Fusobacterium nucleatum/genética , Metástasis Linfática , Proteínas Proto-Oncogénicas p21(ras)/genética , ARN Ribosómico 16S/genética , Neoplasias Colorrectales/genética
2.
Molecules ; 28(10)2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37241738

RESUMEN

The role of inulin in alleviating obesity-related disorders has been documented; yet, its underlying mechanisms still need to be further investigated. This study attempted to elucidate the causative link between the gut microbiota and the beneficial effect of inulin on obesity-related disorders via transferring the fecal microbiota from inulin-dosed mice to high-fat diet (HFD)-induced obese recipient mice. The results show that inulin supplementation can decrease body weight, fat accumulation, and systemic inflammation and can also enhance glucose metabolism in HFD-induced obese mice. Treatment with inulin reshaped the structure and composition of the gut microbiota in HFD-induced obese mice, as characterized by increases in the relative abundances of Bifidobacterium and Muribaculum and decreases in unidentified_Lachnospiraceae and Lachnoclostridium. In addition, we found that these favorable effects of inulin could be partially transferable by fecal microbiota transplantation, and Bifidobacterium and Muribaculum might be the key bacterial genera. Therefore, our results suggest that inulin ameliorates obesity-related disorders by targeting the gut microbiota.


Asunto(s)
Dieta Alta en Grasa , Inulina , Animales , Ratones , Inulina/farmacología , Dieta Alta en Grasa/efectos adversos , Trasplante de Microbiota Fecal , Ratones Obesos , Obesidad/metabolismo , Ratones Endogámicos C57BL
3.
Mol Biol Rep ; 48(4): 3695-3717, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33893928

RESUMEN

Liver cancer is the sixth most common cancer and the fourth leading cause of cancer deaths in the world. The most common type of liver cancers is hepatocellular carcinoma (HCC). Autophagy is the cellular digestion of harmful components by sequestering the waste products into autophagosomes followed by lysosomal degradation for the maintenance of cellular homeostasis. The impairment of autophagy is highly associated with the development and progression of HCC although autophagy may be involved in tumour-suppressing cellular events. In regards to its protecting role, autophagy also shelters the cells from anoikis- a programmed cell death in anchorage-dependent cells detached from the surrounding extracellular matrix which facilitates metastasis in HCC. Liver cancer stem cells (LCSCs) have the ability for self-renewal and differentiation and are associated with the development and progression of HCC by regulating stemness, resistance and angiogenesis. Interestingly, autophagy is also known to regulate normal stem cells by promoting cellular survival and differentiation and maintaining cellular homeostasis. In this review, we discuss the basal autophagic mechanisms and double-faceted roles of autophagy as both tumour suppressor and tumour promoter in HCC, as well as its association with and contribution to self-renewal and differentiation of LCSCs.


Asunto(s)
Autofagia , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/metabolismo , Células Madre Neoplásicas/metabolismo , Animales , Humanos
4.
Int J Mol Sci ; 21(14)2020 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-32659939

RESUMEN

Discovery of a novel anticancer drug delivery agent is important to replace conventional cancer therapies which are often accompanied by undesired side effects. This study demonstrated the synthesis of superparamagnetic magnetite nanocomposites (Fe3O4-NCs) using a green method. Montmorillonite (MMT) was used as matrix support, while Fe3O4 nanoparticles (NPs) and carrageenan (CR) were used as filler and stabilizer, respectively. The combination of these materials resulted in a novel nanocomposite (MMT/CR/Fe3O4-NCs). A series of characterization experiments was conducted. The purity of MMT/CR/Fe3O4-NCs was confirmed by X-ray diffraction (XRD) analysis. High resolution transmission electron microscopy (HRTEM) analysis revealed the uniform and spherical shape of Fe3O4 NPs with an average particle size of 9.3 ± 1.2 nm. Vibrating sample magnetometer (VSM) analysis showed an Ms value of 2.16 emu/g with negligible coercivity which confirmed the superparamagnetic properties. Protocatechuic acid (PCA) was loaded onto the MMT/CR/Fe3O4-NCs and a drug release study showed that 15% and 92% of PCA was released at pH 7.4 and 4.8, respectively. Cytotoxicity assays showed that both MMT/CR/Fe3O4-NCs and MMT/CR/Fe3O4-PCA effectively killed HCT116 which is a colorectal cancer cell line. Dose-dependent inhibition was seen and the killing was enhanced two-fold by the PCA-loaded NCs (IC50-0.734 mg/mL) compared to the unloaded NCs (IC50-1.5 mg/mL). This study highlights the potential use of MMT/CR/Fe3O4-NCs as a biologically active pH-responsive drug delivery agent. Further investigations are warranted to delineate the mechanism of cell entry and cancer cell killing as well as to improve the therapeutic potential of MMT/CR/Fe3O4-NCs.


Asunto(s)
Antineoplásicos/química , Bentonita/química , Carragenina/química , Compuestos Férricos/química , Hidroxibenzoatos/química , Nanocompuestos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Neoplasias Colorrectales/tratamiento farmacológico , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos/efectos de los fármacos , Óxido Ferrosoférrico/química , Tecnología Química Verde/métodos , Células HCT116 , Humanos , Concentración de Iones de Hidrógeno , Hidroxibenzoatos/farmacología , Nanopartículas de Magnetita/química , Tamaño de la Partícula
5.
BMC Biotechnol ; 19(1): 34, 2019 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-31200673

RESUMEN

BACKGROUND: In vitro modelling of cancer cells is becoming more complex due to prevailing evidence of intimate interactions between cancer cells and their surrounding stroma. A co-culture system which consists of more than one cell type is physiologically more relevant and thus, could serve as a useful model for various biological studies. An assay that specifically detects the phenotypic changes of cancer cells in a multi-cellular system is lacking for nasopharyngeal carcinoma (NPC). RESULTS: Here, we describe a luciferase/luciferin (XenoLuc) assay that could specifically measure changes in the proliferation of cancer cells in the co-culture system using two modified NPC patient-derived tumour xenograft (PDTXs) cells: Xeno284-gfp-luc2 and XenoB110-gfp-luc2. Through this assay, we are able to show that the growth of NPC xenograft cells in both two-dimensional (2D) and three-dimensional (3D) models was enhanced when co-cultured with normal human dermal fibroblasts (NHDFs). In addition, potential applications of this assay in in vitro drug or inhibitor screening experiments are also illustrated. CONCLUSIONS: XenoLuc assay is specific, sensitive, rapid and cost-effective for measuring the growth of luciferase-expressing cells in a co- or multiple-culture system. This assay may also be adapted for tumour microenvironment studies as well as drug screening experiments in more complex 3D co-culture systems.


Asunto(s)
Fibroblastos/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Luciferasas/metabolismo , Carcinoma Nasofaríngeo/metabolismo , Animales , Línea Celular Tumoral , Células Cultivadas , Técnicas de Cocultivo , Fibroblastos/citología , Proteínas Fluorescentes Verdes/genética , Células HEK293 , Humanos , Luciferasas/genética , Mediciones Luminiscentes/métodos , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patología , Trasplante Heterólogo
6.
Molecules ; 23(2)2018 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-29415435

RESUMEN

The discovery of highly active antiretroviral therapy (HAART) in 1996 has significantly reduced the global mortality and morbidity caused by the acquired immunodeficiency syndrome (AIDS). However, the therapeutic strategy of HAART that targets multiple viral proteins may render off-target toxicity and more importantly results in drug-resistant escape mutants. These have been the main challenges for HAART and refinement of this therapeutic strategy is urgently needed. Antibody-mediated treatments are emerging therapeutic modalities for various diseases. Most therapeutic antibodies have been approved by Food and Drug Administration (FDA) mainly for targeting cancers. Previous studies have also demonstrated the promising effect of therapeutic antibodies against HIV-1, but there are several limitations in this therapy, particularly when the viral targets are intracellular proteins. The conventional antibodies do not cross the cell membrane, hence, the pathogenic intracellular proteins cannot be targeted with this classical therapeutic approach. Over the years, the advancement of antibody engineering has permitted the therapeutic antibodies to comprehensively target both extra- and intra-cellular proteins in various infections and diseases. This review aims to update on the current progress in the development of antibody-based treatment against intracellular targets in HIV-1 infection. We also attempt to highlight the challenges and limitations in the development of antibody-based therapeutic modalities against HIV-1.


Asunto(s)
Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , Anticuerpos/farmacología , Anticuerpos/uso terapéutico , Permeabilidad de la Membrana Celular , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Animales , Terapia Antirretroviral Altamente Activa , Descubrimiento de Drogas , VIH-1/genética , VIH-1/metabolismo , Humanos , Espacio Intracelular , Terapia Molecular Dirigida , Proteínas Virales/antagonistas & inhibidores , Proteínas Virales/metabolismo , Replicación Viral/efectos de los fármacos
7.
Molecules ; 23(6)2018 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-29882775

RESUMEN

Nanoparticles (NPs) are nano-sized particles (generally 1⁻100 nm) that can be synthesized through various methods. The wide range of physicochemical characteristics of NPs permit them to have diverse biological functions. These particles are versatile and can be adopted into various applications, particularly in biomedical field. In the past five years, NPs' roles in biomedical applications have drawn considerable attentions, and novel NPs with improved functions and reduced toxicity are continuously increasing. Extensive studies have been carried out in evaluating antibacterial potentials of NPs. The promising antibacterial effects exhibited by NPs highlight the potential of developing them into future generation of antimicrobial agents. There are various methods to synthesize NPs, and each of the method has significant implication on the biological action of NPs. Among all synthetic methods, green technology is the least toxic biological route, which is particularly suitable for biomedical applications. This mini-review provides current update on the antibacterial effects of NPs synthesized by green technology using plants. Underlying challenges in developing NPs into future antibacterials in clinics are also discussed at the present review.


Asunto(s)
Antibacterianos/farmacología , Nanopartículas del Metal , Óxidos/química , Plantas/química , Antibacterianos/química , Conservación de los Recursos Naturales , Pruebas de Sensibilidad Microbiana
8.
Pak J Pharm Sci ; 30(2): 449-457, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28649069

RESUMEN

Antibacterial effect is one of the major therapeutic activities of plant-derived Curcumin. This work evaluated the effect of serum albumin, human plasma, and whole blood on the in vitro activity of Curcumin against eight clinical bacterial isolates by standard broth microdilution and plate-counting methods. Toxicological effects of Curcumin towards human red blood cells (RBCs) and peripheral blood mononuclear cells (PBMCs) were also investigated. Curcumin exhibited weak activity against gram-negative bacteria, except Escherichia coli and Shigella flexneri were susceptible and was most active against gram-positive bacteria: Staphylococcus aureus, Streptococcus pyogenes and Enterococcus faecalis. The antibacterial activity was impaired in the presence of bovine serum albumin (BSA), human plasma and whole blood. Curcumin was not toxic to PBMCs and RBCs at 200µg/mL. Furthermore, Curcumin showed synergistic activity in combination with antibiotics: Ciprofloxacin, Gentamicin, Vancomycin and Amikacin against Staphylococcus aureus. This study demonstrated that the interaction of Curcumin with plasma proteins diminishes its in vitro antibacterial activity. Curcumin derivatives with reduced affinity for plasma protein may improve the bioavailability and antibacterial activities.


Asunto(s)
Antibacterianos/farmacología , Fenómenos Fisiológicos Sanguíneos , Curcumina/farmacología , Albúmina Sérica/efectos adversos , Antibacterianos/efectos adversos , Curcumina/efectos adversos , Sinergismo Farmacológico , Eritrocitos/efectos de los fármacos , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Pruebas de Sensibilidad Microbiana
9.
Pak J Pharm Sci ; 30(3): 891-895, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28653935

RESUMEN

This study evaluated the impact of pH (7.4 and 6.5), bovine serum albumin (BSA), and human serum albumin (HSA) on Curcumin activity against 2 reference, 1 clinical, and 10 environmental strains of Staphylococcus aureus (S. aureus). Minimal inhibitory concentrations (MICs) of Curcumin against S. aureus were statistically indifferent (p>0.05) at pH7.4 and pH6.5. Activity of Curcumin against S. aureus was reduced by two folds in the presence of 1.25-5% BSA/HSA.


Asunto(s)
Curcumina/farmacología , Animales , Antibacterianos/farmacología , Bovinos , Humanos , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Pruebas de Sensibilidad Microbiana , Albúmina Sérica/química , Staphylococcus aureus/efectos de los fármacos
10.
Pak J Pharm Sci ; 29(6): 2119-2124, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28375134

RESUMEN

Peptides derived from HIV-1 transmembrane proteins have been extensively studied for antimicrobial activities, and they are known as antimicrobial peptides (AMPs). These AMPs have also been reported to potently combat the drug-resistant microbes. In this study, we demonstrated that peptide #6383 originated from HIV-1 MN strain membrane-spanning domain of gp41 was active (2-log reductions) at 100ßg/mL (56.5ßM) against methicillin-resistant Staphylococcus aureus (MRSA) in 10% and 50% human plasma-supplemented phosphate buffered saline (PBS). The activity was further enhanced (3-log reductions) in the presence of 5% human serum albumin (HSA) alone. All bactericidal activities were achieved within 6 hours. At 100µg/mL, the peptide showed only 13% toxicity against human erythrocytes. This peptide can serve as an attractive template for a design of a novel peptide antibiotic against drug-resistant bacteria. By sequence-specific engineering or modifications, we anticipated that the bactericidal activity and the reduced toxicity against human erythrocytes will be improved.


Asunto(s)
Antibacterianos/farmacología , Proteína gp41 de Envoltorio del VIH/farmacología , VIH-1/química , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Antibacterianos/aislamiento & purificación , Antibacterianos/toxicidad , Relación Dosis-Respuesta a Droga , Eritrocitos/efectos de los fármacos , Proteína gp41 de Envoltorio del VIH/aislamiento & purificación , Hemólisis/efectos de los fármacos , Humanos , Cinética , Staphylococcus aureus Resistente a Meticilina/crecimiento & desarrollo , Viabilidad Microbiana/efectos de los fármacos , Fragmentos de Péptidos/aislamiento & purificación , Fragmentos de Péptidos/toxicidad
11.
Pak J Pharm Sci ; 28(6): 2109-14, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26639480

RESUMEN

This study evaluated the synergistic antibacterial activity of Curcumin with 8 different antibiotic groups. Two reference, one clinical and ten environmental strains of Staphylococcus aureus (S. aureus) were tested. Disc diffusion assay with 25 µg/mL Curcumin demonstrated synergism in combination with a majority of tested antibiotics against S. aureus. However, checkerboard micro dilution assay only showed synergism, fractional inhibitory concentration index (FICI) <0.5 in three antibiotics i.e. Gentamicin, Amikacin, and Ciprofloxacin. Other antibiotics showed indifferent interactions but no antagonism was observed. In time-kill curve, appreciable reduction of bacterial cells was also observed in combination therapy (Curcumin + antibiotics) compared to monotherapy (Curcumin or antibiotic(s) alone). The antibiotics with higher synergistic interaction with Curcumin are arranged in a decreasing order: Amikacin > Gentamicin > Ciprofloxacin.


Asunto(s)
Antibacterianos/farmacología , Curcumina , Extractos Vegetales/farmacología , Staphylococcus aureus/efectos de los fármacos , Amicacina/farmacología , Antibacterianos/aislamiento & purificación , Ciprofloxacina/farmacología , Curcumina/química , Pruebas Antimicrobianas de Difusión por Disco , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Gentamicinas/farmacología , Fitoterapia , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales , Staphylococcus aureus/crecimiento & desarrollo , Factores de Tiempo
12.
Cell Biochem Biophys ; 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38466472

RESUMEN

Hepatocellular carcinoma (HCC) remains a major global health problem with high incidence and mortality. Diagnosis of HCC at late stages and tumour heterogeneity in patients with different genetic profiles are known factors that complicate the disease treatment. HCC therapy becomes even more challenging in patients with drug resistance such as resistance to sorafenib, which is a common drug used in HCC patients. Sorafenib resistance can further aggravate HCC by regulating various oncogenic pathways such as autophagy and nuclear factor-kappa Beta (NF-ĸß) signalling. Sirtuin 1 (SIRT1), is a nicotinamide adenosine dinucleotide (NAD)-dependent histone deacetylases that regulates various metabolic and oncogenic events such as cell survival, apoptosis, autophagy, tumourigenesis, metastasis and drug resistance in various cancers, but its role in HCC, particularly in sorafenib resistance is underexplored. In this study, we generated sorafenib-resistant HepG2 and Huh-7 liver cancer cell models to investigate the role of SIRT1 and its effect on autophagy and nuclear factor-kappa Beta (NF-ĸß) signalling pathways. Western blot analysis showed increased SIRT1, altered autophagy pathway and activated NF-Ä¸ß signalling in sorafenib-resistant cells. SIRT1-silenced HCC cells demonstrated down-regulated autophagy in both parental and chemoresistant cells. This may occur through the deacetylation of key autophagy molecules such as FOXO3, beclin 1, ATGs and LC3 by SIRT1, highlighting the role of SIRT1 in autophagy induction. Silencing of SIRT1 also resulted in activated NF-Ä¸ß signalling. This is because SIRT1 failed to deacetylate p65 subunit of NF-κB, translocate the NF-κB from nucleus to cytoplasm, and suppress NF-κB activity due to the silencing. Hence, the NF-κB transcriptional activity was restored. These findings summarize the role of SIRT1 in autophagy/NF-Ä¸ß regulatory axis, with a similar trend observed in both parental and sorafenib-resistant cells. The present work promotes a better understanding of the role of SIRT1 in autophagy and NF-Ä¸ß signalling in HCC and sorafenib-resistant HCC. As some key proteins in these pathways are potential therapeutic targets, a better understanding of SIRT1/autophagy/NF-Ä¸ß axis could further improve the therapeutic strategies against HCC.

13.
J Mol Histol ; 55(3): 317-328, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38630414

RESUMEN

BACKGROUND: Autophagy plays multifaceted roles in regulating hepatocellular carcinoma (HCC) and the mechanisms involved are under-explored. Regulatory microRNAs (miRNAs) have been reported to target autophagy proteins but their roles in HCC is not well studied. Using HCC patient tissues, this study aims to investigate the association of autophagy with several clinicopathological parameters as well as identifying the autophagy-related miRNAs and the possible pathways. METHODS AND RESULTS: Autophagy level in the HCC patient-derived cancer and non-cancer tissues was determined by immunohistochemistry (IHC) targeting SQSTM1, LC3A and LC3B proteins. Significance tests of clinicopathological variables were tested using the Fisher's exact or Chi-square tests. Gene and miRNA expression assays were carried out and analyzed using Nanostring platform and software followed by validation of other online bioinformatics tools, namely String and miRabel. Autophagy expression was significantly higher in cancerous tissues compared to adjacent non-cancer tissues. High LC3B expression was associated with advanced tumor histology grade and tumor location. Nanostring gene expression analysis revealed that SQSTM1, PARP1 and ATG9A genes were upregulated in HCC tissues compared to non-cancer tissues while SIRT1 gene was downregulated. These genes are closely related to an autophagy pathway in HCC. Further, using miRabel tool, three downregulated miRNAs (hsa-miR-16b-5p, hsa-miR-34a-5p, and hsa-miR-660-5p) and one upregulated miRNA (hsa-miR-539-5p) were found to closely interact with the abovementioned autophagy-related genes. We then mapped out the possible pathway involving the genes and miRNAs in HCC tissues. CONCLUSIONS: We conclude that autophagy events are more active in HCC tissues compared to the adjacent non-cancer tissues. We also reported the possible role of several miRNAs in regulating autophagy-related genes in the autophagy pathway in HCC. This may contribute to the development of potential therapeutic targets for improving HCC therapy. Future investigations are warranted to validate the target genes reported in this study using a larger sample size and more targeted molecular technique.


Asunto(s)
Autofagia , Carcinoma Hepatocelular , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas , MicroARNs , Proteínas Asociadas a Microtúbulos , Proteína Sequestosoma-1 , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Autofagia/genética , Proteína Sequestosoma-1/metabolismo , Proteína Sequestosoma-1/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Asociadas a Microtúbulos/genética , Masculino , Femenino , Persona de Mediana Edad , Anciano , Transducción de Señal/genética , Adulto
14.
BMC Biotechnol ; 13: 107, 2013 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-24304876

RESUMEN

BACKGROUND: HIV genome is packaged and organized in a conical capsid, which is made up of ~1,500 copies of the viral capsid protein p24 (CA). Being a primary structural component and due to its critical roles in both late and early stages of the HIV replication cycle, CA has attracted increased interest as a drug discovery target in recent years. Drug discovery studies require large amounts of highly pure and biologically active protein. It is therefore desirable to establish a simple and reproducible process for efficient production of HIV-1 CA. RESULT: In this work, 6-His-tagged wild type CA from HIV-1 (NL4.3) was expressed in rare tRNA-supplemented NiCo21(DE3) Escherichia coli, and its production was studied in shake flask culture condition of expression. Influences of various key cultivation parameters were examined to identify optimal conditions for HIV-1 CA production. It was found that a culture temperature of 22°C and induction with 0.05 mM IPTG at the early stage of growth were ideal, leading to a maximum biomass yield when grown in Super broth supplemented with 1% glucose. With optimized culture conditions, a final biomass concentration of ~27.7 g L⁻¹ (based on optical density) was obtained in 12 hours post-induction, leading to a yield of about ~170 mg L⁻¹ HIV-1 CA. A two-step purification strategy (chitin beads + IMAC) was employed, which efficiently removed metal affinity resin-binding bacterial proteins that contaminate recombinant His-tagged protein preparation, and resulted in highly pure HIV-1 CA. The purified protein was capable of polymerization when tested in an in vitro polymerization assay. CONCLUSIONS: By using this optimized expression and purification procedure, milligram amounts of highly pure and polymerization-competent recombinant HIV-1 CA can be produced at the lab-scale and thus used for further biochemical studies.


Asunto(s)
Proteínas de la Cápside/biosíntesis , Escherichia coli/genética , Proteína p24 del Núcleo del VIH/biosíntesis , VIH-1/genética , Proteínas de la Cápside/genética , Medios de Cultivo , Escherichia coli/metabolismo , Células HEK293 , Proteína p24 del Núcleo del VIH/genética , VIH-1/fisiología , Humanos , Plásmidos/genética , Polimerizacion , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genética , Replicación Viral
15.
Int J Biol Macromol ; 233: 123388, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36706873

RESUMEN

Polysaccharide-based magnetic nanocomposites can eminently illuminate several attractive features as anticancer drug carriers. In this study, rice straw-based cellulose nanowhisker (CNW) was used as solid support for Fe3O4 nanofillers to synthesize magnetic CNW. Then, cross-linked chitosan-coated magnetic CNW for 5-fluorouracil carrier abbreviated as CH/MCNW/5FU. Fourier-transform infrared, X-Ray diffraction, and X-ray photoelectron spectroscopy analysis indicated successful fabrication and multifunctional properties of the CH/MCNW/5FU nanocomposites. In addition, CH/MCNW/5FU nanocomposites showed hydrodynamic diameter and zeta potential value of 181.31 ± 3.46 nm and +23 ± 1.8 mV, respectively. Based on images of transmission electron microscopy, magnetic CNW as reinforcement was coated with chitosan to obtain almost spherical CH/MCNW/5FU nanocomposites with an average diameter of 37.16 ± 3.08. The nanocomposites indicated desired saturation magnetization and thermal stability, high drug encapsulation efficiency, and pH-dependent swelling and drug release performance. CH/MCNW/5FU nanocomposites showed potent killing effects against colorectal cancer cells in both 2D monolayer and 3D spheroid models. These findings suggest CH/MCNW as a potential carrier for anticancer drugs with high tumour-penetrating capacity.


Asunto(s)
Quitosano , Neoplasias Colorrectales , Nanocompuestos , Humanos , Celulosa/química , Quitosano/química , Sistemas de Liberación de Medicamentos , Fluorouracilo/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Fenómenos Magnéticos , Nanocompuestos/química , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X , Liberación de Fármacos
16.
Front Microbiol ; 14: 1194292, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37577438

RESUMEN

This study presents a green synthesis approach for the fabrication of zinc oxide-silver nanoparticles (ZnO-Ag-NPs) using Punica granatum fruit peels extract as a natural reducing and stabilizing agent. This eco-friendly method offers a sustainable alternative to conventional methods that often employ toxic or hazardous chemicals. Antibacterial and anti-cancer activities of the green synthesized nanoparticles were then assessed in vitro. X-ray diffraction confirmed the production of ZnO-Ag-NPs with increasing crystallinity in higher pH values. The ZnO-Ag-NPs were found to be agglomerated with spherical Ag-NPs. Fourier Transform Infrared (FTIR) spectra revealed a broad band in ZnO-Ag-NPs ranging from 400-1 to 530 cm-1 with reduced intensity as compared to ZnO-NPs, indicating the formation of Ag-NPs on the surface of ZnO-NPs. The synthesized ZnO-Ag-NPs exhibited potent antibacterial activity against a broad spectrum of bacterial strains, particularly Gram-positive bacteria, with superior inhibition activity compared to ZnO-NPs. Moreover, ZnO-Ag-NPs showed a dose-dependent anti-proliferative effect on colorectal-, lung-, and cervical cancer cells. ZnO-Ag-NPs showed significantly greater efficacy in inhibiting cancer cell growth at a lower concentration of 31.25 µg/mL, compared to ZnO-NPs which required over 500 µg/mL, possibly due to the presence of silver nanoparticles (Ag-NPs). The results obtained from this study demonstrate the potential of green synthesis approaches in the fabrication of therapeutic nanomaterials for cancer treatment, as well as other biomedical applications.

17.
Int J Nanomedicine ; 18: 3535-3575, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37409027

RESUMEN

Chemotherapy is the most prominent route in cancer therapy for prolonging the lifespan of cancer patients. However, its non-target specificity and the resulting off-target cytotoxicities have been reported. Recent in vitro and in vivo studies using magnetic nanocomposites (MNCs) for magnetothermal chemotherapy may potentially improve the therapeutic outcome by increasing the target selectivity. In this review, magnetic hyperthermia therapy and magnetic targeting using drug-loaded MNCs are revisited, focusing on magnetism, the fabrication and structures of magnetic nanoparticles, surface modifications, biocompatible coating, shape, size, and other important physicochemical properties of MNCs, along with the parameters of the hyperthermia therapy and external magnetic field. Due to the limited drug-loading capacity and low biocompatibility, the use of magnetic nanoparticles (MNPs) as drug delivery system has lost traction. In contrast, MNCs show higher biocompatibility, multifunctional physicochemical properties, high drug encapsulation, and multi-stages of controlled release for localized synergistic chemo-thermotherapy. Further, combining various forms of magnetic cores and pH-sensitive coating agents can generate a more robust pH, magneto, and thermo-responsive drug delivery system. Thus, MNCs are ideal candidate as smart and remotely guided drug delivery system due to a) their magneto effects and guide-ability by the external magnetic fields, b) on-demand drug release performance, and c) thermo-chemosensitization under an applied alternating magnetic field where the tumor is selectively incinerated without harming surrounding non-tumor tissues. Given the important effects of synthesis methods, surface modifications, and coating of MNCs on their anticancer properties, we reviewed the most recent studies on magnetic hyperthermia, targeted drug delivery systems in cancer therapy, and magnetothermal chemotherapy to provide insights on the current development of MNC-based anticancer nanocarrier.


Asunto(s)
Hipertermia Inducida , Neoplasias , Humanos , Hipertermia Inducida/métodos , Sistemas de Liberación de Medicamentos/métodos , Neoplasias/tratamiento farmacológico , Magnetismo , Campos Magnéticos
18.
Appl Radiat Isot ; 198: 110875, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37257265

RESUMEN

Review is provided of a number of low-dose, low dose rate situations that in study require advances in the development of dosimetric facilities. Using a clinical linac set up to provide doses down to the few mGy level, the performance of a real-time radioluminescence system has then been illustrated, accommodating pulsed as well as continuous dose delivery. The system gate times provide for tracking of the pattern of dose delivery, allowing detailed account of dose and dose-rate variations. The system has been tested in both x-ray and electron mode dose delivery.


Asunto(s)
Radiometría , Radiometría/métodos , Radiografía , Dosificación Radioterapéutica , Rayos X
19.
Pharmaceuticals (Basel) ; 16(1)2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36678607

RESUMEN

There are six members of the transmembrane 4 superfamily (TM4SF) that have similar topology and sequence homology. Physiologically, they regulate tissue differentiation, signal transduction pathways, cellular activation, proliferation, motility, adhesion, and angiogenesis. Accumulating evidence has demonstrated, among six TM4SF members, the regulatory roles of transmembrane 4 L6 domain family members, particularly TM4SF1, TM4SF4, and TM4SF5, in cancer angiogenesis, progression, and chemoresistance. Hence, targeting derailed TM4SF for cancer therapy has become an emerging research area. As compared to others, this review aimed to present a focused insight and update on the biological roles of TM4SF1, TM4SF4, and TM4SF5 in the progression, metastasis, and chemoresistance of various cancers. Additionally, the mechanistic pathways, diagnostic and prognostic values, and the potential and efficacy of current anti-TM4SF antibody treatment were also deciphered. It also recommended the exploration of other interactive molecules to be implicated in cancer progression and chemoresistance, as well as potential therapeutic agents targeting TM4SF as future perspectives. Generally, these three TM4SF members interact with different integrins and receptors to significantly induce intracellular signaling and regulate the proliferation, migration, and invasion of cancer cells. Intriguingly, gene silencing or anti-TM4SF antibody could reverse their regulatory roles deciphered in different preclinical models. They also have prognostic and diagnostic value as their high expression was detected in clinical tissues and cells of various cancers. Hence, TM4SF1, TM4SF4, and TM4SF5 are promising therapeutic targets for different cancer types preclinically and deserve further investigation.

20.
Front Mol Biosci ; 9: 997471, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36304924

RESUMEN

Colorectal cancer is one of the most killing cancers and this has become a global problem. Current treatment and anticancer drugs cannot specifically target the cancerous cells, thus causing toxicity towards surrounding non-cancer cells. Hence, there is an urgent need to discover a more target-specific therapeutic agent to overcome this problem. Core-shell nanoparticles have emerged as good candidate for anticancer treatment. This study aimed to synthesize core-shell nanoparticles via green method which utilised crude peels extract of Garcinia mangostana as reducing and stabilising agents for drug delivery. Gold-silver core-shell nanoparticles (Au-AgNPs) were synthesized through seed germination process in which gold nanoparticles acted as the seed. A complete coating was observed through transmission electron microscopy (TEM) when the ratio of AuNPs and AgNPs was 1:9. The size of Au-AgNPs was 38.22 ± 8.41 nm and was mostly spherical in shape. Plant-based drug, protocatechuic acid (PCA) was loaded on the Au-AgNPs to investigate their anticancer activity. In HCT116 colon cancer cells, PCA-loaded Au-AgNPs (IC50 = 10.78 µg/ml) showed higher inhibitory action than the free PCA (IC50= 148.09 µg/ml) and Au-AgNPs alone (IC50= 24.36 µg/ml). Up to 80% inhibition of HCT116 cells was observed after the treatment of PCA-loaded Au-AgNPs at 15.63 µg/ml. The PCA-loaded Au-AgNPs also showed a better selectivity towards HCT116 compared to CCD112 colon normal cells when tested at the same concentrations. These findings suggest that Au-AgNPs system can be used as a potent nanocarrier to combat cancerous cells by offering additional anticancer properties to the loaded drug.

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