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1.
Heliyon ; 10(7): e28492, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38571665

RESUMO

Introduction: miRNAs originating from colorectal cancer (CRC) tissue receive significant focus in the early diagnosis of CRC due to their stability in body fluids. However, if these miRNAs originated from alternative organs, their prognostic value will diminish. Thus, in this study, we aim to identify disease-specific miRNAs for colorectal cancer (CRC) by employing bioinformatics and experimental methodologies. Method: To identify CRC-specific miRNAs, we retrieved miRNA profiles of CRC and normal tissues from the Cancer Genome Atlas (TCGA) database. Subsequently, computational strategies were utilized to select potential candidate miRNAs. Following this, the expression levels of the potent miRNAs were assessed through RT-qPCR in both CRC tissue and serum samples from patients (N = 46), as well as healthy individuals (N = 46). Additionally, the associations between clinicopathological characteristics, survival outcomes, and diagnostic accuracy were evaluated. Results: A total of 8893 RNA-seq expression data were acquired from TCGA, comprising 8250 data from 19 distinct cancer types and 643 corresponding healthy samples. Based on the computational methodology, miR-549a, miR-552, and miR-592 were identified as the principal expressed miRNAs in colorectal cancer (CRC). Within these miRNAs, miR-552 displayed a substantial association with tumors at the N and T stages. miR-549a and miR-592 were observed to be linked exclusively to the invasion of tumor depth and tumor stage (TNM), respectively. The receiver operating characteristic (ROC) analysis conducted on the miRNA expression in serum samples revealed that all miRNAs exhibited an area under the ROC curve (AUC) of up to 0.86, thereby indicating their high diagnostic accuracy. Conclusion: Considering the strong associations of these three identified miRNAs with CRC, they can collectively serve as a panel for specific discrimination of CRC from other types of cancer within the body. Although this study focused solely on CRC, this approach can potentially be applied to other cancer types as well.

2.
J Biomol Struct Dyn ; 40(20): 10153-10161, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34154515

RESUMO

Understanding the atomic interaction mechanism between chitosan and insulin at different pH levels is essential in the design of chitosan-based drug-delivery systems. In the present study, insulin-loaded nanoparticles were prepared via ionic gelation of tripolyphosphate (TPP) and chitosan with 76 ± 5.5% encapsulation efficiency. Our results showed that the nanoparticles were spherical with a size of 254 nm. Furthermore, the in vitro release profile of insulin was evaluated for two different pH levels. The release of insulin from nanoparticles after 48 h at pH 4.0 was 92%, compared to 56% at pH 7.4. The kinetics of the release were best fitted by the Weibull equation, which described a burst release in the first five hours followed by a sustained insulin release for up to 48 h. Moreover, we designed a long single chain chitosan (128 kDa)/TPP nanoparticles in real size for the first time and studied the system behavior in acidic and neutral environments using molecular dynamic simulation for 40 nanoseconds (ns). Our results showed that chitosan chains opened more with higher root-mean-square deviation (RMSD) values at pH 4.0 than at pH 7.4. Also, RMSD plots for insulin and TPP molecules showed that insulin molecules diffused away from chitosan chains, and that TPP were randomly dispersed further away from the chitosan chain in an acidic medium than in a neutral one. The in silico studies were in agreement with our in vitro data. Thus self-assembled chitosan/TPP nanoparticles show promise as a means to release protein drugs in acidic environments.Communicated by Ramaswamy H. Sarma.


Assuntos
Quitosana , Nanopartículas , Quitosana/química , Insulina , Portadores de Fármacos/química , Simulação de Dinâmica Molecular , Tamanho da Partícula , Nanopartículas/química , Concentração de Íons de Hidrogênio
3.
Front Mol Biosci ; 9: 1030749, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36589227

RESUMO

Introduction: MicroRNAs have a significant role in the regulation of the transcriptome. Several miRNAs have been proposed as potential biomarkers in different malignancies. However, contradictory results have been reported on the capability of miRNA biomarkers in cancer detection. The human biological clock involves molecular mechanisms that regulate several genes over time. Therefore, the sampling time becomes one of the significant factors in gene expression studies. Method: In the present study, we have tried to find miRNAs with minimum fluctuation in expression levels at different time points that could be more accurate candidates as diagnostic biomarkers. The small RNA-seq raw data of ten healthy individuals across nine-time points were analyzed to identify miRNAs with stable expression. Results: We have found five oscillation patterns. The stable miRNAs were investigated in 779 small-RNA-seq datasets of eleven cancer types. All miRNAs with the highest differential expression were selected for further analysis. The selected miRNAs were explored for functional pathways. The predominantly enriched pathways were miRNA in cancer and the P53-signaling pathway. Finally, we have found seven miRNAs, including miR-142-3p, miR-199a-5p, miR-223-5p, let-7d-5p, miR-148b-3p, miR-340-5p, and miR-421. These miRNAs showed minimum fluctuation in healthy blood and were dysregulated in the blood of eleven cancer types. Conclusion: We have found a signature of seven stable miRNAs which dysregulate in several cancer types and may serve as potential pan-cancer biomarkers.

4.
Int J Mol Sci ; 21(15)2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32756480

RESUMO

The pandemic of coronavirus disease 2019 (COVID-19), with rising numbers of patients worldwide, presents an urgent need for effective treatments. To date, there are no therapies or vaccines that are proven to be effective against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Several potential candidates or repurposed drugs are under investigation, including drugs that inhibit SARS-CoV-2 replication and block infection. The most promising therapy to date is remdesivir, which is US Food and Drug Administration (FDA) approved for emergency use in adults and children hospitalized with severe suspected or laboratory-confirmed COVID-19. Herein we summarize the general features of SARS-CoV-2's molecular and immune pathogenesis and discuss available pharmacological strategies, based on our present understanding of SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV) infections. Finally, we outline clinical trials currently in progress to investigate the efficacy of potential therapies for COVID-19.


Assuntos
Imunidade Adaptativa , Betacoronavirus/fisiologia , Infecções por Coronavirus/patologia , Pneumonia Viral/patologia , Anti-Inflamatórios/uso terapêutico , Antivirais/uso terapêutico , Betacoronavirus/isolamento & purificação , COVID-19 , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Infecções por Coronavirus/virologia , Humanos , Imunoterapia , Coronavírus da Síndrome Respiratória do Oriente Médio/isolamento & purificação , Coronavírus da Síndrome Respiratória do Oriente Médio/fisiologia , Fases de Leitura Aberta/genética , Pandemias , Pneumonia Viral/imunologia , Pneumonia Viral/terapia , Pneumonia Viral/virologia , SARS-CoV-2
5.
Cancer Manag Res ; 12: 973-980, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104079

RESUMO

BACKGROUND AND AIMS: MicroRNAs including miR146a have a regulatory role on the expression of genes and act with binding to 3'-UTR region of the genes. Cyclooxygenase-2 (COX-2) is involved in carcinogenesis as an inflammatory marker, and microRNA-146a (miR-146a) as a negative regulatory factor. We aimed to evaluate miR146a expression as a prognostic or diagnostic biomarker for esophageal squamous cell carcinoma (ESCC) and also an association between miR146a and COX2 expression. MATERIALS AND METHODS: We quantified the level of miR-146a and COX-2 expression in cancerous and adjacent normal tissue samples obtained from 34 patients with ESCC, using real-time-PCR. Statistical analyses were conducted using one-sample t-test. Receiver-operating characteristic (ROC) curve and Kaplan-Meier analysis were applied to assay miR146a as a diagnostic and prognostic marker, respectively, during 4 years of the study. Furthermore, the Cox regression model was performed to assay the hazard ratio (HR). The association between miR-146a and COX2 expression level in ESCC patients was evaluated by nonparametric Spearman's rho analysis. RESULTS: The results revealed a reduction of miR-146a expression in 50% of cancerous tissue when compared with adjacent normal regions (P-value=0.127). COX-2 expression in 80% of ESCC patients was higher than in the controls (P-value=0.001). Overall, in 60% of cases, direct association was seen between microRNA-146a and COX-2 expression level (correlation coefficient= 0.438, P-value=0.011). COX2 can be considered as a diagnostic biomarker (AUC=0.834, sensitivity=72%, specificity =83%, P-value<0.0001) but miR146a cannot be considered as a diagnostic biomarker (AUC=0.553, sensitivity=88%, specificity =28%, P-value=0.453). Survival analysis by Kaplan-Meier method showed miR146a and COX2 expression can be probably considered as prognostic biomarkers for ESCC because patients with high expression of miR146a had 7 months shorter life span and patients with low expression of COX2 had 8 months shorter life span. CONCLUSION: COX2 expression is a diagnostic biomarker. MiR-146a and COX2 expression can probably be considered as prognostic biomarkers for survival in ESCC.

6.
Int J Pharm ; 572: 118710, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31629731

RESUMO

The smart self-regulated drug delivery systems for insulin administration are desirable to achieve glycemic control, and decrease the long-term micro- and macro vascular complications. In this study, we developed an injectable nano-complex formulation for closed-loop insulin delivery after subcutaneous administration and release of insulin in response to increased blood glucose levels. The nano-complex was prepared by mixing oppositely charged chitosan and PLGA nanoparticles. PLGA nanoparticles were prepared using double-emulsion solvent diffusion method, and were loaded with glucose oxidase (GOx) and catalase (CAT) enzymes. These negatively charged particles decrease micro-environmental pH, by gluconic acid production in the glucose molecules presence. Positively charged chitosan nanoparticles were prepared using ionic gelation method, and were loaded with insulin. These nanoparticles (NPs) released insulin by dissociation in acidic pH caused by the GOx activity. Following in vitro studies, in vivo evaluation of nano-complex formulations in streptozocin induced diabetic rats showed significant glycemic regulation up to 98 h after subcutaneous administration.


Assuntos
Quitosana/administração & dosagem , Diabetes Mellitus Experimental/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Glucose Oxidase/administração & dosagem , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Nanopartículas/administração & dosagem , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/administração & dosagem , Animais , Glicemia/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Diabetes Mellitus Experimental/sangue , Composição de Medicamentos , Liberação Controlada de Fármacos , Glucose Oxidase/química , Hipoglicemiantes/química , Insulina/química , Masculino , Camundongos , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Ratos Wistar
7.
Eur J Med Chem ; 132: 42-62, 2017 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-28340413

RESUMO

Histone deacetylases (HDACs) are attractive therapeutic targets for the treatment of cancer and other diseases. It has four classes (I-IV), among them especially class I isozyme are involved in promoting tumor cells proliferation, angiogenesis, differentiation, invasion and metastasis and also viable targets for cancer therapeutics. A novel series of coumarin-based benzamides was designed and synthesized as HDAC inhibitors. The cytotoxic activity of the synthesized compounds (8a-u) was evaluated against six human cancer cell lines including HCT116, A2780, MCF7, PC3, HL60 and A549 and a single normal cell line (Huvec). We evaluated their inhibitory activities against pan HDAC and HDAC1 isoform. Four compounds (8f, 8q, 8r and 8u) showed significant cytotoxicity with IC50 in the range of 0.53-57.59 µM on cancer cells and potent pan-HDAC inhibitory activity (consists of HDAC isoenzymes) (IC50 = 0.80-14.81 µM) and HDAC1 inhibitory activity (IC50 = 0.47-0.87 µM and also, had no effect on Huvec (human normal cell line) viability (IC50 > 100 µM). Among them, 8u displayed a higher potency for HDAC1 inhibition with IC50 value of 0.47 ± 0.02 µM near equal to the reference drug Entinostat (IC50 = 0.41 ± 0.06 µM). Molecular docking studies and Molecular dynamics simulation of compound 8a displayed possible mode of interaction between this compound and HDAC1enzyme.


Assuntos
Antineoplásicos/síntese química , Benzamidas/síntese química , Cumarínicos/síntese química , Inibidores de Histona Desacetilases/síntese química , Antineoplásicos/farmacologia , Benzamidas/farmacologia , Linhagem Celular Tumoral , Cumarínicos/farmacologia , Desenho de Fármacos , Histona Desacetilase 1/antagonistas & inibidores , Inibidores de Histona Desacetilases/farmacologia , Humanos , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Relação Estrutura-Atividade
8.
J Biomol Struct Dyn ; 34(11): 2505-17, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26609886

RESUMO

Pesticide detection is a main concern of food safety experts. Therefore, it is urgent to design an accurate, rapid, and cheap test. Biosensors that detect pesticide residues could replace current methods, such as HPLC or GC-MC. This research designs a biosensor based on aptamer (Oligonucleotide ss-DNA) in the receptor role, silver nanoparticles (AgNPs) as optical sensors and salt (NaCl) as the aggregative inducer of AgNPs to detect the presence of Acetamiprid. After optimization, .6 µM aptamer and 100 mM salt were employed. The selectivity and sensitivity of the complex were examined by different pesticides and different Acetamiprid concentrations. To simulate in vitro experimental conditions, bioinformatics software was used as in silico analysis. The results showed the detection of Acetamiprid at the .02 ppm (89.8 nM) level in addition to selectivity. Docking outputs introduced two loops as active sites in aptamer and confirmed aptamer-Acetamiprid bonding. Circular dichroism spectroscopy (CD) confirmed upon Acetamiprid binding, aptamer was folded due to stem-loop formation. Stability of the Apt-Acetamiprid complex in a simulated aqueous media was examined by molecular dynamic studies.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Nanopartículas Metálicas/química , Piridinas/química , Dicroísmo Circular , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Nanotecnologia , Neonicotinoides , Prata , Relação Estrutura-Atividade
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