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1.
J Nanobiotechnology ; 21(1): 313, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37661273

RESUMO

The regeneration of cutaneous tissue is one of the most challenging issues in human regenerative medicine. To date, several studies have been done to promote cutaneous tissue healing with minimum side effects. The healing potential of polyurethane (PU)/Poly (caprolactone)-poly (ethylene glycol)-poly (caprolactone) (PCEC)/chitosan (CS) (PCS) nanofibrous mat with cationic photosensitizer meso tetrakis (N-methyl pyridinium-4-yl) porphyrin tetratosylate salt (TMP) was examined. The CS tripolyphosphate nanoparticles (CSNPs) were prepared and loaded by TMP to provide an efficient drug release system (TMPNPs) for delivery of TMP to promote wound healing. In in vitro setting, parameters such as bactericidal effects, cytocompatibility, and hemolytic effects were examined. The healing potential of prepared nanofibrous mats was investigated in a rat model of full-thickness cutaneous injury. PCS/TMP/TMPNPs nanofibers can efficiently release porphyrin in the aqueous phase. The addition of TMPNPs and CS to the PU backbone increased the hydrophilicity, degradation, and reduced mechanical properties. The culture of human fetal foreskin fibroblasts (HFFF2) on PCS/TMP/TMPNPs scaffold led to an increased survival rate and morphological adaptation analyzed by MTT and SEM images. Irradiation with a red laser (635 nm, 3 J/cm2) for the 30 s reduced viability of S. aureus and E. Coli bacteria plated on PCS/TMP and PCS/TMP/TMPNPs nanofibrous mats compared to PU/PCEC (PC) and PU/PCEC/CS (PCS) groups, indicating prominent antibacterial effects of PCS/TMP and PCS/TMP/TMPNPs nanofibrous (p < 0.05). Data indicated that PCS/TMP/TMPNPs mat enhanced healing of the full-thickness excisional wound in a rat model by the reduction of inflammatory response and fibrotic changes compared to the PC, and PCS groups (p < 0.05). Immunofluorescence imaging indicated that levels of Desmoglein were increased in rats that received PCS/TMP/TMPNPs compared to the other groups. It is found that a PU-based nanofibrous mat is an appropriate scaffold to accelerate the healing of injured skin.


Assuntos
Nanofibras , Animais , Ratos , Humanos , Nanofibras/uso terapêutico , Poliuretanos , Escherichia coli , Staphylococcus aureus , Cicatrização , Antibacterianos/farmacologia
2.
J Mater Sci Mater Med ; 34(10): 47, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37735291

RESUMO

Numerous infections are linked to Pseudomonas aeruginosa. It is one of the major medical concerns because of virulence and antibiotic resistance. Antibiotic encapsulation in liposomes is a good strategy for controlling infections caused by this microorganism. Evaluation of anti-Pseudomonas aeruginosa effect of liposomal form of Imipenem/Cilastatin in vitro condition. By using the disk agar diffusion technique, the isolates' pattern of antibiotic resistance was identified. The antibiotic was placed into the nanoliposome after it had been made using the thin layer and ethanol injection techniques. SEM and DLS were used to determine the size, shape, and zeta potential of the encapsulated drug form and the empty nanoliposome. Additionally, Imipenem/Cilastatin encapsulation in nanoliposomes was studied using FT-IR spectroscopy. In the microbial assay experiments the MIC, MBC and MBEC of liposomal and free drug forms were determined. The nanoparticles were spherical, with a diameter ranging from 30 to 39 nm, and the EE% in the thin layer and ethanol injection procedures were 97 and 98, respectively. Imipenem/Cilastatin nanoliposomes showed peaks at 3009 cm-1 and 1650 cm-1, demonstrating the thermodynamic stability for the chemical structure of the drug enclosed and validating the encapsulation of antibiotic in the nanoliposomes. When compared to free drug forms, nanoliposomes had lower MIC and MBC values in the majority of the isolates and had a greater ability to eradicate the biofilm formation. It was shown that the two nanoliposome preparation techniques were more efficient in 80% of the isolates, which had outcomes that were consistent with those of numerous other investigations. Overall, we demonstrated that the antibacterial activity of nanoliposomes was higher than that of the free drug form based on the evaluation of their MIC and MBC. Pharmaceutical nanoliposome techniques provide an excellent future perspective on how to manage microbial infections that are resistant to antibiotics.


Assuntos
Antibacterianos , Pseudomonas aeruginosa , Espectroscopia de Infravermelho com Transformada de Fourier , Combinação Imipenem e Cilastatina , Antibacterianos/farmacologia , Etanol , Lipossomos , Biofilmes
3.
Biosensors (Basel) ; 13(2)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36831982

RESUMO

Listeria monocytogenes (L.M.) is a gram-positive bacillus with wide distribution in the environment. This bacterium contaminates water sources and food products and can be transmitted to the human population. The infection caused by L.M. is called listeriosis and is common in pregnant women, immune-deficient patients, and older adults. Based on the released statistics, listeriosis has a high rate of hospitalization and mortality; thus, rapid and timely detection of food contamination and listeriosis cases is necessary. During the last few decades, biosensors have been used for the detection and monitoring of varied bacteria species. These devices are detection platforms with great sensitivity and low detection limits. Among different types of biosensors, electrochemical biosensors have a high capability to circumvent several drawbacks associated with the application of conventional laboratory techniques. In this review article, different electrochemical biosensor types used for the detection of listeriosis were discussed in terms of actuators, bioreceptors, specific working electrodes, and signal amplification. We hope that this review will facilitate researchers to access a complete and comprehensive template for pathogen detection based on the different formats of electrochemical biosensors.


Assuntos
Técnicas Biossensoriais , Listeria monocytogenes , Listeriose , Gravidez , Humanos , Feminino , Idoso , Listeriose/epidemiologia , Listeriose/microbiologia , Contaminação de Alimentos/análise , Técnicas Biossensoriais/métodos , Eletrodos , Microbiologia de Alimentos
4.
Cell Commun Signal ; 21(1): 19, 2023 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-36691072

RESUMO

As a common belief, most viruses can egress from the host cells as single particles and transmit to uninfected cells. Emerging data have revealed en bloc viral transmission as lipid bilayer-cloaked particles via extracellular vesicles especially exosomes (Exo). The supporting membrane can be originated from multivesicular bodies during intra-luminal vesicle formation and autophagic response. Exo are nano-sized particles, ranging from 40-200 nm, with the ability to harbor several types of signaling molecules from donor to acceptor cells in a paracrine manner, resulting in the modulation of specific signaling reactions in target cells. The phenomenon of Exo biogenesis consists of multiple and complex biological steps with the participation of diverse constituents and molecular pathways. Due to similarities between Exo biogenesis and virus replication and the existence of shared pathways, it is thought that viruses can hijack the Exo biogenesis machinery to spread and evade immune cells. To this end, Exo can transmit complete virions (as single units or aggregates), separate viral components, and naked genetic materials. The current review article aims to scrutinize challenges and opportunities related to the exosomal delivery of viruses in terms of viral infections and public health. Video Abstract.


Assuntos
Exossomos , Viroses , Vírus , Humanos , Exossomos/metabolismo , Viroses/metabolismo , Transdução de Sinais , Vírion
5.
Bioprocess Biosyst Eng ; 45(12): 1905-1917, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36269380

RESUMO

Recent studies demonstrated that the speed of synthesis, biocompatibility, and antimicrobial activity of gold (Au) and silver (Ag) metals is enhanced when biosynthesized in nano-sized particles. In the present study, Au- and Ag-based nanoparticles (NPs) were synthesized via a biological process using aqueous Ginger root extract and characterized by various spectroscopic methods. The NPs have hexagonal and spherical shapes. The average particle size for Au and Ag NPs was 20 and 15 nm, respectively. The dynamic light scattering (DLS) technique has shown that the zeta potential values of synthesized NPs were 4.8 and - 7.11 mv, respectively. Gas chromatography-mass spectrometry (GC-MS) analysis of Ginger root extract revealed 25 compounds. The synthesized NPs showed significant activity against Staphylococcus aureus and Escherichia (E). coli in vitro, with IC50 and IC90 values for Au and Ag NPs, respectively, noted to be 7.5 and 7.3 µg/ml and 15 and 15.2 µg/ml for both bacterial strains. The protein leakage level was tremendous and morphological changes occurred in bacteria treated with biosynthesized NPs. These results suggest that the biosynthesized metallic NPs have the suitable potential for application as antibacterial agents with enhanced activities.


Assuntos
Nanopartículas Metálicas , Ouro/farmacologia , Ouro/química , Prata/química , Nanopartículas Metálicas/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antibacterianos/química , Bactérias/metabolismo , Testes de Sensibilidade Microbiana
6.
Biomed Mater ; 17(6)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36150376

RESUMO

Biocompatible hydrogels are promising approaches for bone repair and engineering. A novel therapeutic nanocomposite hydrogel was designed based on triblock copolymer poly e-caprolactone (PCL)-polyethylene glycol-PCL and natural gelatin (PCEC/GEL) and reinforced with halloysite nanotube (HNT). Gentamicin (GM) loaded HNT was immobilized in polymeric hydrogel matrix to fabricate scaffolds using the freeze-drying method. Scaffolds were characterized via Fourier transform infrared (FT-IR), x-ray powder diffraction, and scanning electron microscope (SEM) methods. The swelling ratio, density, porosity, degradation, and mechanical behavior were evaluated to investigate the effects of HNT on the physicochemical properties of the composite. Cell viability and cell attachment were investigated by microculture tetrazolium (MTT) assay and SEM. Cell proliferation was observed without any cytotoxicity effect on human dental pulp-derived mesenchymal stem cells (h-DPSCs). Alizarin red staining and real-time reverse transcription polymerase chain reaction (QRT-PCR) assay were carried out to monitor the osteoconductivity of scaffolds on h-DPSCs which were seeded drop wise onto the top of scaffolds. The quantification of the messenger RNA (mRNA) expression of osteogenic marker genes, bone morphogenetic protein 2, SPARK, bone gamma-carboxyglutamate protein and runt-related transcription factor 2 over a period of 21 d of cell seeding, demonstrated that cell-encapsulating PCEC/GEL/HNT-GM hydrogel scaffolds supported osteoblast differentiation of h-DPSCs into osteogenic cells through the up-regulation of related genes along with moderate effects on cell viability. Moreover, the antibiotics loading reduced bacterial growth while maintaining the osteogenic properties of the scaffold. Therefore, the bactericidal PCEC/GEL/HNT-GM hydrogel nanocomposite, with enhanced durability, maintenance the functionality of seeded cellsin vitrothat can be a remarkable dual-functional candidate for hard tissue reconstruction and customized bone implants fabrication via the direct incorporation of bactericidal drug to prevent infection.


Assuntos
Hidrogéis , Nanocompostos , Ácido 1-Carboxiglutâmico/farmacologia , Antibacterianos/farmacologia , Proteína Morfogenética Óssea 2/farmacologia , Regeneração Óssea , Diferenciação Celular , Proliferação de Células , Argila , Subunidade alfa 1 de Fator de Ligação ao Core , Gelatina , Gentamicinas , Humanos , Hidrogéis/química , Nanocompostos/química , Nanogéis , Polietilenoglicóis , RNA Mensageiro/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Engenharia Tecidual/métodos , Tecidos Suporte/química
7.
J Appl Biomater Funct Mater ; 20: 22808000221111875, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35906767

RESUMO

Bone tissue engineering, as an alternative for common available therapeutic approaches, has been developed to focus on reconstructing of the missing tissues and restoring their functionality. In this work, three-dimensional (3D) nanocomposite scaffolds of polycaprolactone-polyethylene glycol-polycaprolactone/gelatin (PCEC/Gel) were prepared by freeze-drying method. Biocompatible nanohydroxyapatite (nHA), iron oxide nanoparticle (Fe3O4) and halloysite nanotube (HNT) powders were added to the polymer matrix aiming to combine the osteogenic activity of nHA or Fe3O4 with high mechanical strength of HNT. The scanning electron microscope (SEM) methods was utilized to characterize the nanotube morphology of HNT as well as nanoparticles of Fe3O4 and nHA. Prepared scaffolds were characterized via Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), and SEM methods. In addition, the physical behavior of scaffolds was evaluated to explore the influence of HNT on the physicochemical properties of composites. Cell viability and attachment were investigated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assay and SEM on human dental pulp-derived mesenchymal stem cells (h-DPSCs) in-vitro. Cell proliferation was observed without any cytotoxicity effect on h-DPSCs for all examined scaffolds. Alizarin red (ARS) and alkaline phosphatase (ALP) staining were carried out to determine the osteoconductivity of scaffolds. The data demonstrated that all PCEC/Gel/HNT hydrogel scaffolds supported osteoblast differentiation of hDPSCs with moderate effects on cell proliferation. Moreover, PCEC/Gel/HNT/nHA with proper mechanical strength showed better biological activity compared to PCEC/Gel/HNT/Fe3O4 and PCEC/Gel/HNT scaffolds. Therefore, this study suggested that with proper fillers content, PCEC/Gel/HNT nanocomposite hydrogels alone or in a complex with nHA, Fe3O4 could be a suitable candidate for hard tissue regeneration.


Assuntos
Hidrogéis , Nanotubos , Proliferação de Células , Argila , Durapatita/química , Gelatina/farmacologia , Humanos , Hidrogéis/farmacologia , Osteogênese , Engenharia Tecidual , Tecidos Suporte/química
8.
Adv Pharm Bull ; 12(1): 58-76, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35517891

RESUMO

Antibiotic resistance is one of the serious health-threatening issues globally, the control of which is indispensable for rapid diagnosis and treatment because of the high prevalence and risks of pathogenicity. Traditional and molecular techniques are relatively expensive, complex, and non-portable, requiring facilities, trained personnel, and high-tech laboratories. Widespread and timely-detection is vital to the better crisis management of rapidly spreading infective diseases, especially in low-tech regions and resource-limited settings. Hence, the need for inexpensive, fast, simple, mobile, and accessible point-of-care (POC) diagnostics is highly demanding. Among different biosensing methods, the isothermal amplification of nucleic acids is favorite due to their simplicity, high sensitivity/specificity, rapidity, and portability, all because they require a constant temperature to work. Isothermal amplification methods are utilized for detecting various targets, including DNA, RNA, cells, proteins, small molecules, ions, and viruses. In this paper, we discuss various platforms, applications, and potentials of isothermal amplification techniques for biosensing of antimicrobial resistance. We also evaluate the potential of these methods, coupled with the novel and rapidly-evolving platforms offered by nanotechnology and microfluidic devices.

9.
Adv Pharm Bull ; 11(4): 675-683, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34888214

RESUMO

Purpose: This study aimed to design gentamicin-conjugated poly (amidoamine) (PAMAM) dendrimers to increase the therapeutic efficiency of gentamicin against Pseudomonas aeruginosa. Methods: Gentamicin-presenting dendrimers were synthesized using MAL-PEG3400-NHS as a redox-sensitive linker to attach gentamicin to the surface of G4 PAMAM dendrimers. The gentamicin molecules were thiolated by using Traut reagent. Then, the functionalized gentamicin molecules were attached to PEGylated PAMAM dendrimers through simple and high selectively maleimide (MAL)-thiol reaction. The structure of gentamicin-conjugated PAMAM dendrimers was characterized and confirmed using nuclear magnetic resonance (NMR), dynamic light scattering (DLS), zeta potential analysis, and transmission electron microscopy (TEM) imaging. The antibacterial properties of the synthesized complex were examined on P. aeruginosa and compared to gentamycin alone. Results: NMR, DLS, zeta potential analysis, and TEM imaging revealed the successful conjugation of gentamicin to PAMAM dendrimers. Data showed the appropriate physicochemical properties of the synthesized nanoparticles. We found a 3-fold increase in the antibacterial properties of gentamicin conjugated to the surface of PAMAM dendrimers compared to non-conjugated gentamicin. Based on data, the anti-biofilm effects of PAMAM-Gentamicin dendrimers increased at least 13 times more than the gentamicin in normal conditions. Conclusion: Data confirmed that PAMAM dendrimer harboring gentamicin could be touted as a novel smart drug delivery system in infectious conditions.

10.
Public Health Rev ; 42: 1604061, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34381626

RESUMO

Background: In late December 2019, a new infectious respiratory disease (COVID-19) was reported in a number of patients with a history of exposure to the Huanan seafood market in China. The World Health Organization officially announced the COVID-19 pandemic on March 11, 2020. Here, we provided an overview of the epidemiologic, diagnostic and treatment approaches associated with COVID-19. Methods: We reviewed the publications indexed in major biomedical databases by December 20, 2020 or earlier (updated on May 16, 2021). Search keywords included a combination of: COVID-19, Coronavirus disease 2019, SARS-CoV-2, Epidemiology, Prevention, Diagnosis, Vaccine, and Treatment. We also used available information about COVID-19 from valid sources such as WHO. Results and Conclusion: At the time of writing this review, while most of the countries authorized COVID-19 vaccines for emergency use starting December 8, 2020, there is no a definite cure for it. This review synthesizes current knowledge of virology, epidemiology, clinical symptoms, diagnostic approaches, common treatment strategies, novel potential therapeutic options for control and prevention of COVID-19 infection, available vaccines, public health and clinical implications.

11.
Int Immunopharmacol ; 92: 107365, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33440306

RESUMO

Emerging beta-coronaviruses (ß-CoVs), including Severe Acute Respiratory Syndrome CoV-1 (SARS-CoV-1), Middle East Respiratory Syndrome-CoV (MERS-CoV), and Severe Acute Respiratory Syndrome CoV-2 (SARS-CoV-2, the cause of COVID19) are responsible for acute respiratory illnesses in human. The epidemiological features of the SARS, MERS, and new COVID-19 have revealed sex-dependent variations in the infection, frequency, treatment, and fatality rates of these syndromes. Females are likely less susceptible to viral infections, perhaps due to their steroid hormone levels, the impact of X-linked genes, and the sex-based immune responses. Although mostly inactive, the X chromosome makes the female's immune system more robust. The extra immune-regulatory genes of the X chromosome are associated with lower levels of viral load and decreased infection rate. Moreover, a higher titer of the antibodies and their longer blood circulation half-life are involved in a more durable immune protection in females. The activation rate of the immune cells and the production of TLR7 and IFN are more prominent in females. Although the bi-allelic expression of the immune regulatory genes can sometimes lead to autoimmune reactions, the higher titer of TLR7 in females is further associated with a stronger anti-viral immune response. Considering these sex-related differences and the similarities between the SARS, MERS, and COVID-19, we will discuss them in immune responses against the ß-CoVs-associated syndromes. We aim to provide information on sex-based disease susceptibility and response. A better understanding of the evasion strategies of pathogens and the host immune responses can provide worthful insights into immunotherapy, and vaccine development approaches.


Assuntos
Betacoronavirus , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Infecções Respiratórias/imunologia , Infecções Respiratórias/virologia , Antivirais/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Feminino , Humanos , Masculino , Infecções Respiratórias/tratamento farmacológico , Fatores Sexuais
12.
Nanomedicine (Lond) ; 16(2): 97-107, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33442986

RESUMO

Background: Preclinical and clinical studies show that local and systemic antitumor efficacy is achievable by in situ vaccination (ISV) using plant virus nanoparticles in which immunostimulatory reagents are directly administered into the tumor rather than systemically. Aim: To investigate a minimally studied plant virus nanoparticle, alfalfa mosaic virus (AMV), for ISV treatment of 4T1, the very aggressive and metastatic murine triple-negative breast cancer model. Materials & methods: AMV nanoparticles were propagated and characterized. Their treatment impact on in vivo tumors were analyzed using determination of inherent immunogenicity, cytokine analysis, western blotting analysis and immunohistochemistry methodologies. Results: AMV used as an ISV significantly slowed down tumor progression and prolonged survival through immune mechanisms (p < 0.001). Conclusion: Mechanistic studies show that ISV with AMV increases costimulatory molecules, inflammatory cytokines and immune effector cell infiltration and downregulates immune-suppressive molecules.


Assuntos
Vírus do Mosaico da Alfafa , Nanopartículas , Neoplasias , Animais , Imunidade , Imunoterapia , Camundongos , Vacinação
13.
Infect Drug Resist ; 13: 1377-1385, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32494169

RESUMO

BACKGROUND: Carbapenem-resistant Enterobacteriaceae (CRE) is a major concern leading to morbidity and mortality in the world. CRE often is becoming a cause of therapeutic failure in both hospital and community-acquired infections. AIM: This study aimed to investigate the resistance mechanisms of CRE by phenotypic and molecular methods. MATERIALS AND METHODS: Sixty CRE (50 Klebsiella pneumoniae, 6 Escherichia coli, and 4 Enterobacter spp.) were isolated from October 2018 to June 2019. Antimicrobial susceptibility testing was carried out using phenotypic methods. The carbapenem resistance mechanisms including efflux pump hyperexpression, AmpC overproduction, carbapenemase genes, and deficiency in OmpK35 and OmpK36 were determined by phenotypic and molecular methods, respectively. RESULTS: Sixty CRE (50 Klebsiella pneumoniae, 6 Escherichia coli, and 4 Enterobacter spp.) were isolated from October 2018 to June 2019. Amikacin was found to be the most effective drug against CRE isolates. All isolates were resistant to imipenem and meropenem by the micro-broth dilution. AmpC overproduction was observed in all Enterobacter spp. and three K. pneumoniae isolates. No efflux pump activity was found. Carba NP test and Modified Hodge Test could find carbapenemase in 59 (98%) isolates and 57 (95%) isolates, respectively. The most common carbapenemase gene was bla OXA-48-like (72.8%) followed by bla NDM (50.8%), bla IMP (18.6%), bla VIM (11.8%), and bla KPC (6.7%). The ompK35 and ompK36 genes were not detected in 10 and 7 K. pneumoniae isolates, respectively. CONCLUSION: The amikacin is considered as a very efficient antibiotic for the treatment of CRE isolates in our region. Carbapenemase production and overproduction of AmpC are the main carbapenem resistance mechanisms in CRE isolates. Finally, Carba NP test is a rapid and reliable test for early detection of carbapenemase-producing isolates.

14.
Curr Microbiol ; 77(9): 2356-2364, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32377819

RESUMO

Piperacillin (Pip) is a broad spectrum ß-lactam against most Gram-positive and Gram-negative aerobic and anaerobic bacteria. However, bacterial resistance restricts its benefits for the treatment of infectious diseases. Recently, nanoliposomal systems have been investigated as encouraging strategies to address this issue owing to their immense potential. We aimed to encapsulate Pip in liposomal nanoparticles and study their antibacterial activities in vitro against Pseudomonas aeruginosa (P. aeruginosa). Different liposomes were prepared based on the freeze-drying of a monophase solution method. Then, they were characterized in terms of size, zeta potential, polydispersity-index, and morphology. For further analysis, spectra of ATR-FTIR and XRD were taken for liposomal Pip. Encapsulation efficiency (EE) was determined via agar diffusion assay. Also, minimum inhibitory concentrations (MICs) were investigated by the standard broth macro-dilution method. The liposomes were from 100.9 to 444.13 nm with z-potential of - 30.70 to - 10.57 mV. EE of the selected formulation was 53.1%. TEM results showed that the liposomes were nanosized and almost spherical. ATR-FTIR results confirmed the full encapsulation of Pip in nanoliposomes. The X-ray pattern indicated that the liposomal Pip was amorphous. The MIC (10.6 µg/ml) of the nanoliposomal Pip against P. aeruginosa was one-half of the MIC (21.25 µg/ml) of free Pip for the same organisms. Considering four aspects (nanosized liposomes, no need for sterilization, suitable EE and enhanced antibacterial effects), this preparation method seems promising and may be used to overcome the bacterial resistance relative to Pip.


Assuntos
Antibacterianos , Piperacilina , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Lipossomos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa
15.
Artigo em Inglês | MEDLINE | ID: mdl-32249552

RESUMO

Nanoparticles have unique capabilities and considerable promise for many different biological uses. One capability is delivering bioactive cargos to specific cells, tissues, or organisms. Depending on the task, there are multiple variables to consider including nanoparticle selection, targeting strategies, and incorporating cargo so it can be delivered in a biologically active form. One nanoparticle option, genetically controlled plant viral nanoparticles (PVNPs), is highly uniform within a given virus but quite variable between viruses with a broad range of useful properties. PVNPs are flexible and versatile tools for incorporating and delivering a wide range of small or large molecule cargos. Furthermore, PVNPs can be modified to create nanostructures that can solve problems in medical, environmental, and basic research. This review discusses the currently available techniques for delivering bioactive cargos with PVNPs and potential cargos that can be delivered with these strategies. This article is categorized under: Implantable Materials and Surgical Technologies > Nanomaterials and Implants Biology-Inspired Nanomaterials > Protein and Virus-Based Structures.


Assuntos
Proteínas do Capsídeo , Sistemas de Liberação de Medicamentos , Nanopartículas , Vírus de Plantas , Nanomedicina , Engenharia de Proteínas , Vírion
16.
J Microbiol Methods ; 164: 105674, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31348953

RESUMO

BACKGROUND & AIMS: Increasing antibiotic resistance among Helicobacter pylori isolates and the unsuccessful attempts at eradication can impose many costs to both healthcare systems and patients. The present study intended to find a way from which H. pylori could be isolated from biopsies with less invasive procedures undertaken on infected patients. METHODS: A biopsy specimen from each patient with gastric disorders was put into urea-containing agar. After two hours, the specimens were removed from agar and placed into tubes containing 1 ml 20% glucose solution. Then, the specimens were inoculated onto the Columbia agar and incubated under microaerophilic conditions. The grown colonies were identified as H.pylori based on the microbiology tests and PCR. RESULTS: Overall, 449 biopsy specimens were collected from the patients. Of all biopsies, 219 (48.8%) revealed positive results in the rapid urease test. Using the aforementioned method, 158 (35.2%) culture positive biopsy specimens were obtained. CONCLUSION: The researchers attempted to use one biopsy specimen for both rapid urease and culture tests. This method causes fewer injuries of gastric tissue and allows antimicrobial susceptibility testing and characterization in detail of the isolated organism.


Assuntos
Biópsia/métodos , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/crescimento & desenvolvimento , Helicobacter pylori/isolamento & purificação , Urease/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Testes Diagnósticos de Rotina/métodos , Feminino , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/microbiologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Estômago/microbiologia , Gastropatias/diagnóstico , Gastropatias/microbiologia , Adulto Jovem
17.
J Microbiol Methods ; 153: 40-44, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30189222

RESUMO

Enterobacteriaceae are a part of the human intestinal flora easily spread by hand carriage, water and food. Treatment of infections due to Enterobacteriaceae is difficult mainly in countries with a low socioeconomic state. Carbapenems are considered as a last-resort antibiotic for the treatment of infections due to multidrug-resistant Enterobacteriaceae. Carbapenem-resistant Enterobacteriaceae (CRE) presents a major threat to public health and are rapidly disseminating globally. The most important resistance mechanism of Enterobacteriaceae to carbapenems is carbapenemase production. The treatment options for CRE are limited; attention is focused here on the rapid detection of CRE. Laboratory surveillance of cultures and screening of patients are essential and desirable in areas where these strains are endemic. Culture-based methods such as chromogenic media are used for the initial detection of these strains. These media offer a sensitive, convenient, and low-cost way of identifying CRE species. This article provides an overview of the current state of culture-based chromogenic screening media for the detection of CRE.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Compostos Cromogênicos/farmacologia , Meios de Cultura/química , Meios de Cultura/farmacologia , Antibacterianos/farmacologia , Proteínas de Bactérias/biossíntese , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Carbapenêmicos/farmacologia , Compostos Cromogênicos/química , Infecções por Enterobacteriaceae/microbiologia , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/enzimologia , Testes de Sensibilidade Microbiana , beta-Lactamases/biossíntese
18.
Artif Cells Nanomed Biotechnol ; 46(sup3): S336-S343, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30043657

RESUMO

Metal nanoparticles (MNPs) produced by green approaches have received global attention because of their physicochemical characteristics and their applications in the field of biotechnology. In recent years, the development of synthesizing NPs by plant extracts has become a major focus of researchers because of these NPs have low hazardous effect in the environment and low toxicity for the human body. Synthesized NPs from plants are not only more stable in terms of size and shape, also the yield of this method is higher than the other methods. Moreover, some of these MNPs have shown antimicrobial activity which is consistently confirmed in past few years. Plant extracts have been used as reducing agent and stabilizer of NPs in which we can reduce the toxicity in the environment as well as the human body only by not using chemical agents. Furthermore, the presence of some specific materials in plant extracts could be extremely helpful and effective for the human body; for instance, polyphenol, which may have antioxidant effects has the capability for capturing free radicals before they can react with other biomolecules and cause serious damages. In this article, we focused on of the most common plants which are regularly used to synthesize MNPs along with various methods for synthesizing MNPs from plant extracts.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/síntese química , Química Verde/métodos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Prata/química , Anti-Infecciosos/uso terapêutico , Humanos , Nanopartículas Metálicas/uso terapêutico
19.
Basic Clin Pharmacol Toxicol ; 121(5): 390-399, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28613449

RESUMO

A series of sila-organosulphur compounds containing 1,2,3-triazole cores were screened for their cytotoxic activity on human breast cancer cell line MCF-7. Most of the tested compounds exhibited moderate-to-good activity against the cancer cells. Especially, the compound 4-((2-(trimethylsilyl)ethynylthio)methyl)-1-benzyl-1H-1,2,3-triazole (3a) from series of sila-substituted thioalkyne 1,2,3-triazoles (STATs) and the compounds 3-(1-benzyl-1H-1,2,3-triazol-4-yl)-1-mercapto-1,1-bis(trimethylsilyl)propane-2-thione (4a) and 1-mercapto-1,1-bis(trimethylsilyl)-3-(1-phenethyl-1H-1,2,3-triazol-4-yl)propane-2-thione (4e) from series of sila-substituted mercapto-thione 1,2,3-triazoles (SMTTs) exhibited promising cytotoxicity against MCF-7 with IC50 values of 35.17, 32.63 and 30.3 µg/mL, respectively. In addition, the possible mechanisms for inhibition of cell growth and induction of apoptotic cell death were explored by DAPI staining, cell cycle analysis and qRT-PCR. The synthetic compounds were evaluated for their in vitro antibacterial activities, and as a result, the most prominent effects were observed for 3e and 4e. Especially, 3e was found to be quite active against all the tested strains with the MIC values ranging from 15 to 62 µg/mL, except P. aeruginosa. The results of the time-kill assay suggested that the compound of 3e completely inhibited the growth of both gram-negative bacteria, A. baumannii, and gram-positive bacteria, S. aureus. In addition, SEM analysis confirmed morphostructural damage of the bacteria. Our findings could be applicable for developing dual-targeting anticancer/antibacterial therapeutics.


Assuntos
Alcinos/farmacologia , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Triazóis/farmacologia , Alcinos/administração & dosagem , Alcinos/química , Antibacterianos/administração & dosagem , Antibacterianos/química , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Feminino , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Células MCF-7 , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tionas/administração & dosagem , Tionas/química , Tionas/farmacologia , Triazóis/administração & dosagem , Triazóis/química
20.
Artif Cells Nanomed Biotechnol ; 45(1): 1-5, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27015806

RESUMO

Diagnosis and treatment of lung cancer have been characterized with a variety of challenges. However, with the advancement in magnetic nanoparticle (MNP) technology, many challenges in the diagnosis and treatment of lung cancer are on the decline. The MNPs have led to many break-through in cancer therapy. This paper seeks to establish the role of MNPs in diagnosis and treatment of lung cancer. It proposes that the existing challenges in the diagnosis and treatment of lung cancer can be addressed through application of MNPs in the process.


Assuntos
Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamento farmacológico , Campos Magnéticos , Nanopartículas/uso terapêutico , Animais , Humanos
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