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1.
Curr Issues Mol Biol ; 45(6): 5005-5017, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37367067

RESUMO

Liver cancer is a prevalent form of cancer worldwide. While research has shown that increasing sphingomyelin (SM) hydrolysis by activating the cell surface membrane-associated neutral sphingomyelinase 2 (nSMase2) can control cell proliferation and apoptosis, the role of total glutathione depletion in inducing tumor cell apoptosis via nSMase2 activation is still under investigation. Conversely, glutathione-mediated inhibition of reactive oxygen species (ROS) accumulation is necessary for the enzymatic activity of nSMase1 and nSMase3, increased ceramide levels, and cell apoptosis. This study evaluated the effects of depleting total glutathione in HepG2 cells using buthionine sulfoximine (BSO). The study assessed nSMases RNA levels and activities, intracellular ceramide levels, and cell proliferation using RT-qPCR, Amplex red neutral sphingomyelinase fluorescence assay, and colorimetric assays, respectively. The results indicated a lack of nSMase2 mRNA expression in treated and untreated HepG2 cells. Depletion of total glutathione resulted in a significant increase in mRNA levels but a dramatic reduction in the enzymatic activity of nSMase1 and nSMase3, a rise in ROS levels, a decrease in intracellular levels of ceramide, and an increase in cell proliferation. These findings suggest that total glutathione depletion may exacerbate liver cancer (HCC) and not support using total glutathione-depleting agents in HCC management. It is important to note that these results are limited to HepG2 cells, and further studies are necessary to determine if these effects will also occur in other cell lines. Additional research is necessary to explore the role of total glutathione depletion in inducing tumor cell apoptosis.

2.
Lipids Health Dis ; 20(1): 150, 2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34717628

RESUMO

Cell surface biochemical changes, notably excessive increase in outer leaflet sphingomyelin (SM) content, are important in cancer initiation, growth, and immune evasion. Innumerable reports describe methods to initiate, promote, or enhance immunotherapy of clinically detected cancer, notwithstanding the challenges, if not impossibility, of identification of tumor-specific, or associated antigens, the lack of tumor cell surface membrane expression of major histocompatibility complex (MHC) class I alpha and ß2 microglobulin chains, and lack of expression or accessibility of Fas and other natural killer cell immune checkpoint molecules. Conversely, SM synthesis and hydrolysis are increasingly implicated in initiation of carcinogenesis and promotion of metastasis. Surface membrane SM readily forms inter- and intra- molecular hydrogen bond network, which excessive tightness would impair cell-cell contact inhibition, inter- and intra-cellular signals, metabolic pathways, and susceptibility to host immune cells and mediators. The present review aims at clarifying the tumor immune escape mechanisms, which face common immunotherapeutic approaches, and attracting attention to an entirely different, neglected, key aspect of tumorigenesis associated with biochemical changes in the cell surface that lead to failure of contact inhibition, an instrumental tumorigenesis mechanism. Additionally, the review aims to provide evidence for surface membrane SM levels and roles in cells resistance to death, failure to respond to growth suppressor signals, and immune escape, and to suggest possible novel approaches to cancer control and cure.


Assuntos
Neoplasias/etiologia , Esfingomielinas/metabolismo , Evasão Tumoral , Animais , Antígenos de Superfície , Carcinogênese/metabolismo , Progressão da Doença , Humanos , Neoplasias/imunologia , Neoplasias/metabolismo
3.
Anal Biochem ; 609: 113890, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-32783900

RESUMO

Foodborne pathogens represent a major public health concern. In this respect, Acinetobacter baumannii is emerging as multi-drug resistant food pathogen. Screening of A. baumannii in food is a lengthy process. The aim of this study is to develop a fast and efficient protocol for detecting A. baumannii as well as other potential pathogens in fresh food. A. baumannii was collected from strawberry samples (n = 93) and were identified by DNA sequencing and polymerase chain reaction (PCR; recA). Hydrophobic magnetic nanoparticles (OA-MNP) were synthesized and tested for capturing A. baumannii and other bacteria from broth medium. Their ability to immobilize bacteria was assessed and the accuracy of PCR performed on immobilized bacteria was compared against control. A. baumannii (n = 14) was isolated form fresh produce as confirmed by sequencing and PCR. OA-MNPs were able to capture A. baumannii as well as other bacteria from broth medium. Intact DNA was extracted from immobilized bacteria and was successfully recruited for subsequent PCR. In conclusion, OA-MNP can be used for immobilizing food pathogens from broth medium. PCR can be performed using DNA extracted from immobilized bacteria for identification. The proposed analysis procedure may shorten the time required for detection of bacterial contamination in food.


Assuntos
Acinetobacter baumannii/genética , Nanopartículas de Magnetita/química , Reação em Cadeia da Polimerase/métodos , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/isolamento & purificação , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , DNA Bacteriano/química , DNA Bacteriano/metabolismo , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Fragaria/microbiologia , Interações Hidrofóbicas e Hidrofílicas , Testes de Sensibilidade Microbiana , Ácido Oleico/química , Análise de Sequência de DNA
4.
Biotechnol Lett ; 42(2): 231-240, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31823154

RESUMO

OBJECTIVES: Citrullus colocynth (CTC) is a wild medicinal plant with proven antimicrobial activity. The aim of this study is to investigate the use of its aqueous extract in producing magnetic iron oxide nanoparticles (MNPs) with improved antimicrobial activity. The cold and hot aqueous extract of seed and pulp parts of CTC, respectively, were used to produce MNPs. The particles were characterized by transmission electron microscope, energy dispersion x-ray, FTIR and their surface charge were measured. The antimicrobial activity of the produced particles was assessed against two Gram positive (Bacillus subtillis and Staphylococcus aureus) and two Gram negative (Escherichia coli and Pseudomonas aeruginosa) bacteria and well as against Candida albicans. RESULTS: MNPs synthesized using cold seed extract (S-MNP) and pulp extract (P-MNP) were spherical in shape. The size distribution was more uniform in the S-MNP (6-15 nm) compared to the P-MNP (12-45 nm). Both particles showed comparable anti-microbial potential against the tested microorganisms. At a concentration range of 0.48-1000 µg/mL, S-MNP inhibited bacterial growth by 16.0-99.0% and 10.0-91.0%; while P-MNP inhibition was 11.0-100.0% and 11.0-99.0% for Gram positive and negative bacteria; respectively. Candida albicans was the least affected microorganism with maximum inhibition of 63-88% after treatment with S-MNP and P-MNP (1 mg/mL), respectively. CONCLUSIONS: The aqueous extract of CTC can be used for synthesis of MNPs with antimicrobial activity. The described procedures are simple and can be modified for large scale green synthesis of MNPs.


Assuntos
Anti-Infecciosos/farmacologia , Citrullus colocynthis/química , Compostos Férricos/química , Extratos Vegetais/farmacologia , Anti-Infecciosos/química , Bacillus subtilis/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Química Verde , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Extratos Vegetais/química , Pseudomonas aeruginosa/efeitos dos fármacos , Sementes/química , Staphylococcus aureus/efeitos dos fármacos
5.
Drug Dev Ind Pharm ; 46(10): 1613-1621, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32806984

RESUMO

Diabetic wound infections and pressure ulcers pose a significant challenge to healthcare providers worldwide. The current study provides new and innovative wound care products that reduce inflammation, clear infection, and improve healing in an animal model of pressure ulcers in diabetic rats. Ointment, hydrogel, and nanofiber dressings were synthesized using 5% turmeric, 1% oregano, and 1% chitosan nanoparticles and tested for antibacterial and cytotoxicity in vitro, and wound healing effects in vivo. Turmeric ethanolic extract showed high antioxidant activity compared to Oregano, Chitosan Nanoparticles, and Alginate silver (p-value < 0.0001). The ointment and hydrogel formulation (5% Turmeric, 1% Oregano, and 1% chitosan) showed lower cytotoxicity compared to the commercial Alginate silver dressing. Ointment, hydrogel formulations, and commercial Alginate silver, showed significant antibacterial activity with 100% efficacy on both Staphylococcus aureus and Escherichia coli (p-value < 0.0001), compared to nanofibers which showed 50% reduction in bacterial growth (p-value < 0.0001). The new formulations were tested in a rat model of pressure ulcers. Ointment and nanofibers achieved complete wound healing by day 15 compared to the hydrogel and commercial Alginate silver dressing, which showed higher infection, and the wound remained partially open by day 21. In conclusion, Turmeric, Oregano extracts, and chitosan nanoparticles can be used for effective wound dressings in both diabetic and non-diabetic wounds. At relatively low concentrations, this combination provides a promising new wound treatment formulation that is antibacterial, anti-inflammatory, and antioxidant.


Assuntos
Curcuma , Diabetes Mellitus Experimental , Origanum , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bandagens , Diabetes Mellitus Experimental/tratamento farmacológico , Ratos , Úlcera/tratamento farmacológico
6.
Lung ; 197(2): 241-247, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30610370

RESUMO

PURPOSE: TB nanodiagnostics have witnessed considerable development. However, most of the published reports did not proceed beyond proof-of-concept. Our objectives are to evaluate the diagnostic accuracy of a novel nanogold assay in detecting patients with active pulmonary TB based on results of BACTEC MGIT (reference test), and to compare its clinical performance to combined use of sputum smear microscopy (SSM) with chest X-ray (CXR). METHODS: This is a case-control study that involved 20 active TB patients; 20 non-TB chest patients with a previous history of TB infection; 20 non-TB chest patients without a previous history of TB infection. RESULTS: Sensitivity and specificity of TB nanogold assay were 95% and 100%, respectively, with diagnostic odds ratio (DOR) of 1053.0. ROC curve analysis yielded an area under curve (AUC) of 0.975. TB nanogold assay generated higher performance than combined use of SSM with CXR. The DOR and AUC differences were 996.0 and 0.125, respectively. CONCLUSIONS: Our study shows that TB nanogold assay is accurate, rapid, and holds the potential for use as an add-on initial test to improve accuracy of SSM and CXR in detecting patients of active pulmonary TB in developing countries. Future studies should involve larger sample size for further assessment of test accuracy.


Assuntos
Ouro , Nanopartículas Metálicas , Nanomedicina/métodos , Tuberculose Pulmonar/diagnóstico , Adulto , Idoso , Feminino , Humanos , Masculino , Microscopia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Radiografia Torácica , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tuberculose Pulmonar/microbiologia , Fluxo de Trabalho
7.
Biomed Chromatogr ; 31(7)2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27977867

RESUMO

Therapeutic drug monitoring (TDM) of anti-epileptic drugs (AED) is a routine application. Carbamazepine (CRB) is monitored as the parent drug while oxcarbazepine (OXC) and eslicarbazepine acetate (ESL) are monitored as their active metabolite (eslicarbazepine; MHD). We have developed a UPLC-MS/MS method for determining CRB, OXC, ESL and MHD in plasma or serum with a simplified extraction protocol. The developed method detects sildenafil (SLD), which clinically interferes with AED and is likely to be co-administered in epileptic patients suffering from sexual insufficiency (60%). MHD was prepared in-house. AED were simultaneously determined in presence of SLD using gatifloxacin as an internal standard (IS). Separation was achieved using acetonitrile, methanol and 100 mm ammonium acetate in water (32:3:65, v/v/v) on an Intersil® RP-HPLC column (250 × 4.6 mm, 5 µm). A one-step extraction was performed by simultaneous protein and phospholipids precipitation. Detection was done by tandem mass spectrometry. No relative matrix effect was observed. The method was linear (0.5-40 µg/mL for CRB, ESL and MHD and 0.05-4 µg/mL for OXC), accurate and selective. Recoveries were 64.41 ± 5.07, 45.62 ± 1.73, 61.41 ± 4.77 and 60.33 ± 1.36 for CRB, OXC, ESL and MHD, respectively. The method was successfully applied for TDM of AED.


Assuntos
Anticonvulsivantes/sangue , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Relação Dose-Resposta a Droga , Humanos , Limite de Detecção , Reprodutibilidade dos Testes
8.
Mol Pharm ; 12(12): 4277-89, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26465978

RESUMO

Many recently discovered therapeutic proteins exert their main function in the nucleus, thus requiring both efficient uptake and correct intracellular targeting. Chitosan nanoparticles (NPs) have attracted interest as protein delivery vehicles due to their biocompatibility and ability to escape the endosomes offering high potential for nuclear delivery. Molecular entry into the nucleus occurs through the nuclear pore complexes, the efficiency of which is dependent on NP size and the presence of nuclear localization sequence (NLS). Chitosan nanoparticles of different sizes (S-NPs ≈ 25 nm; L-NP ≈ 150 nm) were formulated, and they were modified with different densities of the octapeptide NLS CPKKKRKV (S-NPs, 0.25, 0.5, 2.0 NLS/nm(2); L-NPs, 0.6, 0.9, 2 NLS/nm(2)). Unmodified and NLS-tagged NPs were evaluated for their protein loading capacity, extent of cell association, cell uptake, cell surface binding, and finally nuclear delivery efficiency in L929 fibroblasts. To avoid errors generated with cell fractionation and nuclear isolation protocols, nuclear delivery was assessed in intact cells utilizing Förster resonance energy transfer (FRET) fluorometry and microscopy. Although L-NPs showed ≈10-fold increase in protein loading per NP when compared to S-NPs, due to higher cell association and uptake S-NPs showed superior protein delivery. NLS exerts a size and density dependent effect on nanoparticle uptake and surface binding, with a general reduction in NP cell surface binding and an increase in cell uptake with the increase in NLS density (up to 8.4-fold increase in uptake of High-NLS-L-NPs (2 NLS/nm(2)) compared to unmodified L-NPs). However, for nuclear delivery, unmodified S-NPs show higher nuclear localization rates when compared to NLS modified NPs (up to 5-fold by FRET microscopy). For L-NPs an intermediate NLS density (0.9 NLS/nm(2)) seems to provide highest nuclear localization (3.7-fold increase in nuclear delivery compared to High-NLS-L-NPs). Results indicate that a higher NLS density does not result in maximum protein nuclear localization and that a universal optimal density for NPs of different sizes does not exist.


Assuntos
Núcleo Celular/metabolismo , Quitosana/química , Nanopartículas/química , Sinais de Localização Nuclear/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Quitosana/administração & dosagem , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Endossomos/metabolismo , Camundongos , Nanopartículas/administração & dosagem , Sinais de Localização Nuclear/administração & dosagem , Tamanho da Partícula
9.
Clin Chem Lab Med ; 52(4): 565-72, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24158422

RESUMO

BACKGROUND: The unique properties of metallic nanoparticles have enabled their utilization in biosensing applications. A novel assay for the detection of hepatitis C virus (HCV) RNA in serum specimens has been developed using magnetic nanoparticles and unmodified cationic gold nanoparticles (AuNPs). METHODS: HCV RNA was extracted using magnetic nanoparticles functionalized with an oligonucleotide specific to HCV RNA. Extracted RNA is reacted with oligonucleotide sequence specific for HCV RNA in presence of unmodified cationic AuNPs. In positive samples, AuNPs are aligned onto the phosphate backbone of the RNA and their aggregation changes the solution color from red to blue. In the absence of target, solution color remains red. The assay has been tested on 50 serum clinical samples (25 HCV positive and 25 controls). RESULTS: The dual nanoparticles assay detected HCV RNA in serum and generated comparable results to real-time PCR. The assay had specificity and a sensitivity of 96% and 96.5%, respectively, and a detection limit of 15 IU/mL. CONCLUSIONS: The developed colorimetric dual nanoparticles HCV RNA assay is simple and inexpensive and can be used for rapid detection of unamplified HCV RNA in serum. Similar sensing platforms can be developed to detect other nucleic acid targets.


Assuntos
Hepatite C/sangue , Hepatite C/virologia , Nanopartículas Metálicas/química , RNA Viral/sangue , Colorimetria , Humanos , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade
10.
ACS Appl Bio Mater ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39352856

RESUMO

Infections resulting from microorganisms pose an ongoing global public health challenge, necessitating the constant development of novel antimicrobial approaches. Utilizing photocatalytic materials to generate reactive oxygen species (ROS) presents an appealing strategy for combating microbial threats. In alignment with this perspective, sodium titanate nanotubes were prepared by scalable hydrothermal method using TiO2 and NaOH. Ag, Au, and Ag/Au-modified titanate nanotubes (TNTs) were prepared by a cost-effective and simple ion-exchange method. All samples were characterized by XRD, FT-IR, HRTEM, and DLS techniques. HRTEM images indicated that the tubular structure was preserved in all TNTs even after the replacement of Na+ with Ag+ and/or Au3+ ions. The antibacterial activity in dark and sunlight conditions was evaluated using different bacterial strains, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The results showed that while a low bacterial count (∼log 5 cells per well) was used for inoculation, the TNTs exhibited no antibacterial activity against the three bacterial strains, regardless of whether they were tested under light or dark conditions. However, the plasmonic nanoparticle-decorated TNTs showed remarkable activity in the dark. Additionally, Ag/Au-TNTs demonstrated significantly higher activity in the dark compared with either Ag-TNTs or Au-TNTs alone. Notably, under dark conditions, the Au/Ag-TNTs achieved log reductions of up to 4.5 for P. aeruginosa, 5 for S. aureus, and 3.7 for E. coli. However, when exposed to sunlight, Au/Ag-TNTs resulted in a complete reduction (log reduction ∼9) for P. aeruginosa and E. coli. The combination of two plasmonic nanoparticles (Ag/Au) decorated on the surface of TNTs showed synergetic bactericidal activity under both dark and light conditions. Ag/Au-TNTs could be explored to design surfaces that are responsive to visible light and exhibit antimicrobial properties.

11.
Nanoscale Adv ; 6(5): 1361-1373, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38419874

RESUMO

General anaesthetics are routinely used to sedate patients during prolonged surgeries and administered via intravenous injection and/or inhalation. All anaesthetics have short half-lives, hence the need for their continuous administration. This causes several side effects such as pain, vomiting, nausea, bradycardia, and on rare occasions death post-administration. Several clinical trials studied the synergetic effect of a combination of anaesthetic drugs to reduce the drug load. Another solution is to encapsulate anaesthetics in nanoparticles to reduce their dose and side effects as well as achieve their sustained release manner. Different types of nanoparticles were developed as carriers of intravenous and intrathecal anaesthetics generating platforms which facilitate drug transport across the blood-brain barrier (BBB). Nanocarriers encapsulating common anaesthetic drugs such as propofol, etomidate, and ketamine were developed and characterized in terms of size, stability, onset and duration of loss of right reflex, and tolerance to pain in small animal models. The review discusses the types of nanocarriers used to reduce the side effects of the anaesthetic drugs while prolonging the sedation time. More rigorous studies are still required to evaluate the nanocarrier formulations regarding their ability to deliver anaesthetic drugs across the BBB, safety, and finally applicability in clinical settings.

12.
Biomed Mater ; 18(4)2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37285854

RESUMO

Niacin (NA) and zinc (Zn) were used to fabricate metal organic frameworks (Zn-NA MOFs), based on coordination chemistry via a simple, rapid technique conducted at room temperature. The identity of the prepared MOFs was confirmed by Fourier-transform infrared, x-ray diffraction, scanning electron microscopy, and transmission electron microscopy, which showed cubic shaped, crystalline, microporous MOFs with an average size of 150 nm. Release of the active ingredients from the MOFs was proved to be pH dependent in a slightly alkaline medium (pH 8.5) with a sustained release rate of its two ingredients, NA and Zn, which have wound healing activity. Zn-NA MOFs proved to be biocompatible in the tested concentrations range (5-100 mg ml-1), with no cytotoxic effect on WI-38 cell line. Zn-NA MOFs at 10 and 50 mg ml-1concentrations and their components, NA and Zn, exerted antibacterial effects againstStaphylococcus aureus, Escherichia coli, andPseudomonas aeruginosa. Wound healing effect of the Zn-NA MOFs (50 mg ml-1) was evaluated on full excisional rat wounds. Significant reduction of the wound area was observed after 9 d of treatment using the Zn-NA MOFs compared to the other treatment groups. Additionally, wounds were fully healed after 10 d of treatment with the Zn-NA MOFs with histological and immunohistochemical evidence of re-epithelization, collagen formation, and angiogenesis. Similar histological evidence was also observed in wounds treated with niacin only; however, with no significant wound closure rates. Nevertheless, the formation of new blood vessels, as confirmed by the vascular endothelial growth factor protein expression, was highest in the niacin group. Zn-NA MOFs synthesized using a facile, low-cost method are potentially capable of healing wounds rapidly and effectively.


Assuntos
Niacina , Acetato de Zinco , Ratos , Animais , Acetato de Zinco/farmacologia , Niacina/farmacologia , Fator A de Crescimento do Endotélio Vascular/farmacologia , Cicatrização , Zinco/farmacologia , Antibacterianos/farmacologia
13.
Sci Rep ; 13(1): 886, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650180

RESUMO

Wound healing is a well-organized dynamic process involving coordinated consecutive phases: homeostasis, inflammation, proliferation and resolution. Fibroblasts play major roles in skin wound healing such as in wound contraction and release of growth factors which are of importance in angiogenesis and tissue remodeling. Abnormal fibroblast phenotypes have been identified in patients with chronic wounds. In this work, we analyzed scRNA-seq datasets of normal and wounded skin from mice at day 4 post-wound to investigate fibroblast heterogeneity during the proliferative phase of wound healing. Compositional analysis revealed a specific subset of fibroblast (cluster 3) that primarily increased in wounded skin (14%) compared to normal skin (3.9%). This subset was characterized by a gene signature marked by the plasma membrane proteins Sfrp2 + Sfrp4 + Sfrp1 + and the transcription factors Ebf1 + Prrx1 + Maged1 + . Differential gene expression and enrichment analysis identified epithelial to mesenchymal transition (EMT) and angiogenesis to be upregulated in the emerging subset of fibroblasts of the wounded skin. Using two other datasets for murine wounded skin confirmed the increase in cluster 3-like fibroblasts at days 2, 7 and 14 post-wounding with a peak at day 7. By performing a similarity check between the differential gene expression profile between wounded and normal skin for this emerging fibroblast subset with drug signature from the ConnectivityMap database, we identified drugs capable of mimicking the observed gene expression change in fibroblasts during wound healing. TTNPB, verteprofin and nicotinic acid were identified as candidate drugs capable of inducing fibroblast gene expression profile necessary for wound healing. On the other hand, methocarbamol, ifosfamide and penbutolol were recognized to antagonize the identified fibroblast differential expression profile during wound healing which might cause delay in wound healing. Taken together, analysis of murine transcriptomic skin wound healing datasets suggested a subset of fibroblasts capable of inducing EMT and further inferred drugs that might be tested as potential candidates to induce wound closure.


Assuntos
Transição Epitelial-Mesenquimal , Pele , Camundongos , Animais , Pele/metabolismo , Transição Epitelial-Mesenquimal/genética , Cicatrização/genética , Fatores de Transcrição/metabolismo , Fibroblastos , Proteínas de Neoplasias/metabolismo
14.
Anal Bioanal Chem ; 402(3): 1019-27, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22089818

RESUMO

The development of rapid detection assays for malaria diagnostics is an area of intensive research, as the traditional microscopic analysis of blood smears is cumbersome and requires skilled personnel. Here, we describe a simple and sensitive immunoassay that successfully detects malaria antigens in infected blood cultures. This homogeneous assay is based on the fluorescence quenching of cyanine 3B (Cy3B)-labeled recombinant Plasmodium falciparum heat shock protein 70 (PfHsp70) upon binding to gold nanoparticles (AuNPs) functionalized with an anti-Hsp70 monoclonal antibody. Upon competition with the free antigen, the Cy3B-labeled recombinant PfHsp70 is released to solution resulting in an increase of fluorescence intensity. Two types of AuNP-antibody conjugates were used as probes, one obtained by electrostatic adsorption of the antibody on AuNPs surface and the other by covalent bonding using protein cross-linking agents. In comparison with cross-linked antibodies, electrostatic adsorption of the antibodies to the AuNPs surfaces generated conjugates with increased activity and linearity of response, within a range of antigen concentration from 8.2 to 23.8 µg.mL(-1). The estimated LOD for the assay is 2.4 µg.mL(-1) and the LOQ is 7.3 µg.mL(-1). The fluorescence immunoassay was successfully applied to the detection of antigen in malaria-infected human blood cultures at a 3% parasitemia level, and is assumed to detect parasite densities as low as 1,000 parasites.µL(-1).


Assuntos
Antígenos de Protozoários/análise , Imunofluorescência/métodos , Ouro/química , Malária/diagnóstico , Nanopartículas/química , Plasmodium falciparum/isolamento & purificação , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Antígenos de Protozoários/imunologia , Carbocianinas/química , Corantes Fluorescentes/química , Proteínas de Choque Térmico HSP70/análise , Proteínas de Choque Térmico HSP70/imunologia , Humanos , Malária/sangue , Malária/imunologia , Plasmodium falciparum/imunologia , Proteínas de Protozoários/análise , Proteínas de Protozoários/imunologia , Proteínas Recombinantes/análise , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade
15.
Int J Mol Sci ; 13(6): 6534-6547, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22837648

RESUMO

In this study, we investigate the influence of glow discharge plasma (GDP) on the self-assembly, morphology and binding affinity of streptavidin coated gold nanoparticles (Au-NP-SV) and biotinylated antibody (bAb) adsorbed on a highly oriented pyrolytic graphite (HOPG) substrate. Atomic force microscope (AFM) was used to image the pre- and post-GDP treated samples. The analysis of the AFM images showed a considerable change in the aggregation and morphology of Au-NP-conjugates after treatment with GDP. To our knowledge, this is the first report on using GDP to enhance and speed-up the aggregation (sintering) of adsorbed NP biomolecular conjugates. These results show a promising route that could be generalized for other NPs and their conjugates. It can also be considered as an alternative and cheap aggregation method for controlling the binding affinity of biomolecular species on different surfaces with interesting applications.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Estreptavidina/química , Adsorção , Anticorpos/química , Bioensaio , Biotinilação , Grafite/química , Microscopia de Força Atômica , Nanoconjugados/química , Propriedades de Superfície
16.
RSC Adv ; 12(50): 32744-32755, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36425686

RESUMO

Alzheimer's disease (AD) is the most common type of dementia and progresses from mild memory loss to severe decline in thinking, behavioral and social skills, which dramatically impairs a person's ability to function independently. Genetics, some health disorders and lifestyle have all been connected to AD. Also, environmental factors are reported as contributors to this illness. The presence of heavy metals in air, water, food, soil and commercial products has increased tremendously. Accumulation of heavy metals in the body leads to serious malfunctioning of bodily organs, specifically the brain. For AD, a wide range of heavy metals have been reported to contribute to its onset and progression and the manifestation of its hallmarks. In this review, we focus on detection of highly toxic heavy metals such as mercury, cadmium, lead and arsenic in water. The presence of heavy metals in water is very troubling and regular monitoring is warranted. Optical chemosensors were designed and fabricated for determination of ultra-trace quantities of heavy metals in water. They have shown advantages when compared to other sensors, such as selectivity, low-detection limit, fast response time, and wide-range determination under optimal sensing conditions. Therefore, implementing optical chemosensors for monitoring levels of toxic metals in water represents an important contribution in fighting AD.

17.
ACS Omega ; 7(15): 13210-13220, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35474822

RESUMO

The present study describes the development of multifunctional hemostatic sponges to control bleeding. Chitosan (Ch) and poly(vinyl alcohol) (PVA) were selected as the basic polymeric matrix [Ch/PVA] for sponges. Glycerol and citric acid were used as crosslinkers [Ch/PVA/G(Cl)] to enhance the mechanical properties of the developed sponges. Ciprofloxacin (AB) was added to the developed sponge to impart antibacterial activity. Hydroxyapatite (HA) was also added, which would make the sponge suitable for bone surgery. Among the developed sponges, the Ch/PVA/G(Cl)-HA-AB sponge demonstrated enhanced cell viability, mechanical properties, and strong antimicrobial effect against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus, in addition to platelet aggregation activity. The addition of ciprofloxacin and hydroxyapatite promotes a unique synergistic effect of antimicrobial activity and hemostasis. Thus, the present study introduces Ch/PVA/G(Cl)-HA-AB, a multifunctional hemostatic sponge that would be suitable for bone surgical applications.

18.
Cancers (Basel) ; 14(13)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35804809

RESUMO

Early detection of hepatocellular carcinoma (HCC) will reduce morbidity and mortality rates of this widely spread disease. Dysregulation in microRNA (miRNA) expression is associated with HCC progression. The objective is to identify a panel of differentially expressed miRNAs (DE-miRNAs) to enhance HCC early prediction in hepatitis C virus (HCV) infected patients. Candidate miRNAs were selected using a bioinformatic analysis of microarray and RNA-sequencing datasets, resulting in nine DE-miRNAs (miR-142, miR-150, miR-183, miR-199a, miR-215, miR-217, miR-224, miR-424, and miR-3607). Their expressions were validated in the serum of 44 healthy individuals, 62 non-cirrhotic HCV patients, 67 cirrhotic-HCV, and 72 HCV-associated-HCC patients using real-time PCR (qPCR). There was a significant increase in serum concentrations of the nine-candidate miRNAs in HCC and HCV patients relative to healthy individuals. MiR-424, miR-199a, miR-142, and miR-224 expressions were significantly altered in HCC compared to non-cirrhotic patients. A panel of five miRNAs improved sensitivity and specificity of HCC detection to 100% and 95.12% relative to healthy controls. Distinguishing HCC from HCV-treated patients was achieved by 70.8% sensitivity and 61.9% specificity using the combined panel, compared to alpha-fetoprotein (51.4% sensitivity and 60.67% specificity). These preliminary data show that the novel miRNAs panel (miR-150, miR-199a, miR-224, miR-424, and miR-3607) could serve as a potential non-invasive biomarker for HCC early prediction in chronic HCV patients. Further prospective studies on a larger cohort of patients should be conducted to assess the potential prognostic ability of the miRNAs panel.

19.
Clin Chem Lab Med ; 50(2): 193-209, 2011 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-21973106

RESUMO

In order to meet the challenges of effective healthcare, the clinical laboratory is constantly striving to improve testing sensitivity while reducing the required time and cost. Gold nanoparticles (AuNPs) are proposed as one of the most promising tools to meet such goals. They have unique optophysical properties which enable sensitive detection of biomarkers, and are easily amenable to modification for use in different assay formats including immunoassays and molecular assays. Additionally, their preparation is relatively simple and their detection methods are quite versatile. AuNPs are showing substantial promise for effective practical applications and commercial utilization is already underway. This article covers the principles of preparation of AuNPs and their use for development of different diagnostic platforms.


Assuntos
Bioensaio/métodos , Biomarcadores , Ouro/química , Nanopartículas Metálicas/química , Humanos
20.
Sci Rep ; 11(1): 545, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436962

RESUMO

Doxorubicin (DOX) chemotherapy is associated with the release of inflammatory cytokines from macrophages. This has been suggested to be, in part, due to DOX-mediated leakage of endotoxins from gut microflora, which activate Toll-like receptor 4 (TLR4) signaling in macrophages, causing severe inflammation. However, the direct function of DOX on macrophages is still unknown. In the present study, we tested the hypothesis that DOX alone is incapable of stimulating inflammatory response in macrophages. Then, we compared the anti-inflammatory effects of curcumin (CUR), resveratrol (RES) and sulforaphane (SFN) against lipopolysaccharide/interferon-gamma (LPS/IFN-γ)-mediated inflammation in the absence or presence of DOX. For this purpose, RAW 264.7 cells were stimulated with LPS/IFN-γ (10 ng/mL/10 U/mL) in the absence or presence of DOX (0.1 µM). Our results showed that DOX alone is incapable of stimulating an inflammatory response in RAW 264.7 macrophages. Furthermore, after 24 h of incubation with LPS/IFN-γ, a significant increase in tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and inducible nitric oxide synthase (iNOS) mRNA levels was observed. Similarly, nitric oxide (NO) production and TNF-α and IL-6 protein levels were significantly upregulated. Moreover, in LPS/IFN-γ-treated macrophages, the microRNAs (miRNAs) miR-146a, miR-155, and miR-21 were significantly overexpressed. Interestingly, upon testing CUR, RES, and SFN against LPS/IFN-γ-mediated inflammation, only SFN was able to significantly reverse the LPS/IFN-γ-mediated induction of iNOS, TNF-α and IL-6 and attenuate miR-146a and miR-155 levels. In conclusion, SFN, at the transcriptional and posttranscriptional levels, exhibits potent immunomodulatory action against LPS/IFN-γ-stimulated macrophages, which may indicate SFN as a potential treatment for DOX-associated inflammation.


Assuntos
Antibióticos Antineoplásicos/efeitos adversos , Curcumina/farmacologia , Doxorrubicina/efeitos adversos , Fatores Imunológicos , Mediadores da Inflamação/metabolismo , Isotiocianatos/farmacologia , Macrófagos/imunologia , Macrófagos/metabolismo , Resveratrol/farmacologia , Sulfóxidos/farmacologia , Animais , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Interferon gama/efeitos adversos , Interleucina-6/metabolismo , Isotiocianatos/uso terapêutico , Lipopolissacarídeos/efeitos adversos , Camundongos , Terapia de Alvo Molecular , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , RNA Mensageiro/metabolismo , Sulfóxidos/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo
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