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1.
Analyst ; 149(10): 2898-2904, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38572620

RESUMO

Bacterial infections are a leading cause of death globally. The detection of DNA sequences correlated to the causative pathogen has become a vital tool in medical diagnostics. In practice, PCR-based assays for the simultaneous detection of multiple pathogens currently rely on probe-based quantitative strategies that require expensive equipment but have limited sensitivity or multiplexing capabilities. Hence, novel approaches to address the limitations of the current gold standard methods are still in high demand. In this study, we propose a simple multiplex PCR/SERS assay for the simultaneous detection of four bacterial pathogens, namely P. aeruginosa, S. aureus, S. epidermidis, and M. smegmatis. Wherein, specific primers for amplifying each target gDNA were applied, followed by applying SERS nanotags functionalized with complementary DNA probes and Raman reporters for specific identification of the target bacterial pathogens. The PCR/SERS assay showed high specificity and sensitivity for genotyping bacterial pathogen gDNA, whereby as few as 100 copies of the target gDNA could be detected. With high sensitivity and the convenience of standard PCR amplification, the proposed assay shows great potential for the sensitive detection of multiple pathogen infections to aid clinical decision-making.


Assuntos
Bactérias , Reação em Cadeia da Polimerase Multiplex , Análise Espectral Raman , Reação em Cadeia da Polimerase Multiplex/métodos , Bactérias/isolamento & purificação , Bactérias/genética , Análise Espectral Raman/métodos , DNA Bacteriano/análise , DNA Bacteriano/genética , Limite de Detecção , Nanopartículas Metálicas/química , Reação em Cadeia da Polimerase/métodos
2.
Curr Microbiol ; 81(3): 81, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38289473

RESUMO

The evolving clinical resistance in Plasmodium falciparum and the spike in malarial cases after the COVID-19 outbreak has triggered a search for new antimalarials effective against multi-drug-resistant P. falciparum strains. In this study, we assessed the timing of action, either fast or slow-acting of 13 potent compounds of Pandemic Response Box (PRB) against blood-stage Pf3D7 strain by SYBR Green-I assay. The asynchronous culture of Pf3D7 was exposed to varying concentrations of 13 compounds, and IC50 values were determined at 12, 24, 48, 72, and 96 h. We identified four fast-acting compounds (MMV000008, MMV1593541, MMV020752, MMV396785) with rapid-growth inhibitory activity having IC50 values ≤ 0.3 µM at 12 and 24 h. Similarly, we determined nine slow-acting compounds (MMV159340, MMV1634492, MMV1581558, MMV689758, MMV1593540, MMV394033, MMV019724, MMV000725, MMV1557856) having IC50 values ≤ 0.5 µM at 72 and 96 h. Furthermore, the stage-specific action of the two most potent fast-acting compounds (MMV1593541 and MMV020752) against rings, trophozoites, and schizonts at 48 h of exposure revealed that ring-stage parasites showed reduced IC50 values compared to mature stage forms. Therefore, our study demonstrates for the first time the identification of the most potent fast and slow-acting compounds from PRB against blood-stage infection, suggesting its utility in clinics and considering it as a partner drug in combination therapies.


Assuntos
Antimaláricos , Antimaláricos/farmacologia , Plasmodium falciparum , Pandemias , Hemocultura , Bioensaio
3.
Eur Arch Otorhinolaryngol ; 281(8): 3903-3913, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38492009

RESUMO

PURPOSE: Functional endoscopic sinus surgery (FESS) is a mainstay surgical intervention for chronic rhinosinusitis with nasal polyposis (CRSwNP). Nasal irrigation, particularly with normal saline, is a widely recommended postoperative care modality. This systematic review and meta-analysis aimed to assess the efficacy of various nasal irrigation solutions in postoperative FESS patients. METHODS: A comprehensive search was conducted in multiple databases for randomized controlled trials investigating normal saline and various substances for nasal irrigation post-FESS. The systematic review followed PRISMA guidelines, and the meta-analysis used R software for data synthesis. Outcome measures included SNOT-22 and LKES scores. The Cochrane tool was employed to evaluate the potential for bias. RESULTS: Results from 14 studies, focusing on six each for SNOT-22 and LKES, revealed a significant reduction in symptoms and endoscopic scores with various solutions compared to normal saline. The meta-analysis using the random-effects model indicated a negative standardized mean difference (SMD) of - 0.69(95% CI [- 1.64; 0.27], p = 0.157) for symptoms and endoscopic scores (SMD = - 0.48, 95% CI [- 1.32; 0.36], z = - 1.12, p = 0.264). Subgroup analyses highlighted budesonide's efficacy over normal saline, but substantial heterogeneity and potential publication bias were noted. CONCLUSION: Nasal irrigation with various solutions postoperative FESS patients demonstrated significant improvements in patient-reported symptoms and endoscopic scores compared to normal saline. Budesonide appeared particularly effective. However, high heterogeneity and potential publication bias warrant cautious interpretation. Standardized outcome measures and further research are needed to strengthen the evidence.


Assuntos
Endoscopia , Lavagem Nasal , Pólipos Nasais , Cuidados Pós-Operatórios , Rinite , Sinusite , Humanos , Sinusite/cirurgia , Lavagem Nasal/métodos , Rinite/cirurgia , Endoscopia/métodos , Doença Crônica , Pólipos Nasais/cirurgia , Cuidados Pós-Operatórios/métodos , Resultado do Tratamento
4.
Drug Dev Res ; 85(5): e22233, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39030842

RESUMO

Malaria is an intracellular protozoan parasitic disease caused by Plasmodium species with significant morbidity and mortality in endemic regions. The complex lifecycle of the parasite and the emergence of drug-resistant Plasmodium falciparum have hampered the efficacy of current anti-malarial agents. To circumvent this situation, the present study attempts to demonstrate the blood-stage anti-plasmodial action of 26 hybrid compounds containing the three privileged bioactive scaffolds (sulfonamide, chalcone, and nitro group) with synergistic and multitarget action. These three parent scaffolds exhibit divergent activities, such as antibacterial, anti-malarial, anti-fungal, anti-inflammatory, and anticancer. All the synthesised compounds were characterised using various spectroscopic techniques. The in vitro blood-stage inhibitory activity of 26 hybrid compounds was evaluated against mixed-stage culture (asynchronize) of human malarial parasite P. falciparum, Pf 3D7 at different concentrations ranging from 25.0 µg/mL to 0.78 µg/mL using SYBR 1 green assay, with IC50 values determined after 48 h of treatment based on the drug-response curves. Two potent compounds (11 and 10), with 2-Br and 2,6-diCl substitutions, showed pronounced activity with IC50 values of 5.4 µg/mL and 5.6 µg/mL, whereas others displayed varied activity with IC50 values ranging from 7.0 µg/mL to 22.0 µg/mL. Both 11 and 10 showed greater susceptibility towards mature-stage trophozoites than ring-stage parasites. The hemolytic and in vitro cytotoxicity assays revealed that compounds 11 and 10 did not cause any toxic effects on host red blood cells (uninfected), human-derived Mo7e cells, and murine-derived BA/F3 cells. The in vitro observations are consistent with the in silico studies using P. falciparum-dihydrofolate reductase, where 11 and 10 showed a binding affinity of -10.4 Kcal/mol. This is the first report of the hybrid scaffold, 4-nitrobenzenesulfonamide chalcones, demonstrating its potential as an anti-plasmodial agent.


Assuntos
Antimaláricos , Chalconas , Desenho de Fármacos , Plasmodium falciparum , Plasmodium falciparum/efeitos dos fármacos , Antimaláricos/farmacologia , Antimaláricos/síntese química , Antimaláricos/química , Chalconas/farmacologia , Chalconas/síntese química , Chalconas/química , Humanos , Simulação de Acoplamento Molecular , Sulfonamidas/farmacologia , Sulfonamidas/química , Sulfonamidas/síntese química , Simulação por Computador , Relação Estrutura-Atividade , Tetra-Hidrofolato Desidrogenase/metabolismo
5.
Curr Microbiol ; 80(8): 273, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37414909

RESUMO

The emergence of SARS-CoV-2 and its variants have posed a significant threat to humankind in tackling the viral spread. Furthermore, currently repurposed drugs and frontline antiviral agents have failed to cure severe ongoing infections effectively. This insufficiency has fuelled research for potent and safe therapeutic agents to treat COVID-19. Nonetheless, various vaccine candidates have displayed a differential efficacy and need for repetitive dosing. The FDA-approved polyether ionophore veterinary antibiotic for treating coccidiosis has been repurposed for treating SARS-CoV-2 infection (as shown by both in vitro and in vivo studies) and other deadly human viruses. Based on selectivity index values, ionophores display therapeutic effects at sub-nanomolar concentrations and exhibit selective killing ability. They act on different viral targets (structural and non-structural proteins), host-cell components leading to SARS-CoV-2 inhibition, and their activity is further enhanced by Zn2+ supplementation. This review summarizes the anti-SARS-CoV-2 potential and molecular viral targets of selective ionophores like monensin, salinomycin, maduramicin, CP-80,219, nanchangmycin, narasin, X-206 and valinomycin. Ionophore combinations with Zn2+ are a new therapeutic strategy that warrants further investigation for possible human benefits.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Ionóforos/farmacologia , Ionóforos/uso terapêutico , Reposicionamento de Medicamentos , Monensin/farmacologia , Antivirais/farmacologia , Antivirais/uso terapêutico
6.
Crit Rev Clin Lab Sci ; 58(2): 77-100, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32609551

RESUMO

The reliable detection of nucleic acids at low concentrations in clinical samples like blood, urine and saliva, and in food can be achieved by nucleic acid amplification methods. Several portable and hand-held devices have been developed to translate these laboratory-based methods to point-of-care (POC) settings. POC diagnostic devices could potentially play an important role in environmental monitoring, health, and food safety. Use of a smartphone for nucleic acid testing has shown promising progress in endpoint as well as real-time analysis of various disease conditions. The emergence of smartphone-based POC devices together with paper-based sensors, microfluidic chips and digital droplet assays are used currently in many situations to provide quantitative detection of nucleic acid targets. State-of-the-art portable devices are commercially available and rapidly emerging smartphone-based POC devices that allow the performance of laboratory-quality colorimetric, fluorescent and electrochemical detection are described in this review. We present a comprehensive review of smartphone-based POC sensing applications, specifically on microbial diagnostics, assess their performance and propose recommendations for the future.


Assuntos
Ácidos Nucleicos , Sistemas Automatizados de Assistência Junto ao Leito , Humanos , Técnicas de Amplificação de Ácido Nucleico , Testes Imediatos , Smartphone , Tecnologia
7.
Analyst ; 146(18): 5714-5721, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34515700

RESUMO

The molecular diagnosis of KRAS mutations has become crucial for clinical decision-making in colorectal cancer (CRC) treatments. Currently, the common methods for detecting mutations are based on quantitative PCR, DNA sequencing and droplet digital PCR (ddPCR), which require expensive specialized equipment and testing reagents. Herein, we propose a simple and specific strategy by integrating asymmetric PCR with surface-enhanced Raman spectroscopy (Asy-PCR/SERS) for the detection of KRAS G12V mutation, one of the most common driver mutations in CRC. To discriminate mutant targets from non-targets, Asy-PCR was applied to obtain single-stranded DNA (ssDNA) with unequal amounts of forward and reverse primers, subsequently, detection of the target mutant ssDNA amplicons was attempted by hybridization with Raman reporter-coded and allele-specific oligonucleotide-functionalized gold nanoparticles (SERS nanotags). The oligo encoding of the KRAS G12V mutant sequence could be identified by using a portable Raman spectrometer where the characteristic spectra of SERS nanotags indicate the presence of mutant targets. The Asy-PCR/SERS method showed high specificity and sensitivity for identifying as few as 0.1% mutant alleles of KRAS G12V mutation from non-target sequences. Using colorectal polyp biopsies, we demonstrated that Asy-PCR/SERS assay could distinguish KRAS G12V (c.35G > T) and KRAS G12D (c.35G > A) which occur at the same nucleotide location. As KRAS G12V is a driver oncogene in other cancers including lung, pancreatic, ovarian and endometrial cancers, the proposed assay shows great potential for application in additional tumor streams.


Assuntos
Neoplasias Colorretais , Nanopartículas Metálicas , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Ouro , Humanos , Mutação , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas p21(ras)/genética
8.
Parasitol Res ; 120(10): 3341-3353, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34423387

RESUMO

The appearance of increasing drug resistance in apicomplexan intracellular Plasmodium falciparum presents a significant challenge. P. falciparum infection results in cerebral malaria (CM), causing irreversible damage to the brain leading to high mortality cases. To enhance the clinical outcome of the disease, further research is required to identify new molecular targets involved in disease manifestations. Presently, the role of non-coding microRNAs (miRNAs) derived from different cells implicated in CM pathogenesis is still barely understood. Despite the absence of miRNA machinery in Plasmodium, host-parasite interactions can lead to disease severity or impart resistance to malaria. Cytoadherence and sequestration of parasitized RBCs dysregulate the miRNA profile of brain endothelial cells, leukocytes, monocytes, and platelets, disrupting blood-brain barrier integrity and activating inflammatory signaling pathways. The abundance of miRNA in blood plasma samples of CM patients directly correlates to cerebral symptoms compared to non-CM patients and healthy individuals. Moreover, the differential host-miRNA signatures distinguish P. falciparum from P. vivax infection. Here, we review the diverse functions of host-miRNA, either protective, pathogenic, or a combination of the two, which may act as prognostic markers and novel antimalarial drug targets.


Assuntos
Malária Cerebral , Malária Falciparum , MicroRNAs , Animais , Biomarcadores , Células Endoteliais , Humanos , Malária Cerebral/tratamento farmacológico , Malária Falciparum/tratamento farmacológico , MicroRNAs/genética , Plasmodium falciparum
9.
Anal Chem ; 92(8): 5708-5716, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32223184

RESUMO

Efficient DNA mutation detection methods are required for diagnosis, personalized therapy development, and prognosis assessment for diseases such as cancer. To address this issue, we proposed a straightforward approach by combining active plasmonic nanostructures, surface-enhanced Raman spectroscopy (SERS), and polymerase chain reaction (PCR) with a statistical tool to identify and classify BRAF wild type (WT) and V600E mutant genes. The nanostructures provide enhanced sensitivity, while PCR offers high specificity toward target DNA. A series of positively charged plasmonic nanostructures including gold/silver nanospheres, nanoshells, nanoflowers, and nanostars were synthesized with a one-pot strategy and characterized. By changing the shape of nanostructures, we are able to vary the surface plasmon resonance from 551 to 693 nm. The gold/silver nanostar showed the highest SERS activity, which was employed for DNA mutation detection. We reproducibly analyzed as few as 100 copies of target DNA sequences using gold/silver nanostars, thus demonstrating the high sensitivity of the direct SERS detection. By means of statistical analysis (principal component analysis-linear discriminant analysis), this method was successfully applied to differentiate the WT and V600E mutant both from whole genome DNA lysed from cell line and from cell-free DNA collected from cell culture media. We further proved that this assay is capable of specifically amplifying and accurately classifying a real plasma sample. Thus, this direct SERS strategy combined with the active plasmonic nanostructures has the potential for wide applications as an alternative tool for sensitively monitoring and evaluating important clinical nucleotide biomarkers.


Assuntos
DNA/genética , Nanoestruturas/química , Animais , Bovinos , Humanos , Mutação , Análise Espectral Raman , Células Tumorais Cultivadas
10.
Analyst ; 145(7): 2789-2794, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32101179

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) is considered to be one of the important hospital-acquired pathogens. MRSA is also commonly associated with hospital-acquired infections and mortality. Quantitative and precise detection of MRSA is essential for rapid diagnosis and subsequent effective disease management strategies. We herein developed a highly specific method for rapid MRSA detection that combines surface-enhanced Raman spectroscopy (SERS) nanotags and polymerase chain reaction (PCR). SERS provided the sensitivity and spectral multiplexing capability while PCR provided the specificity required for the assay. The method was tested by the simultaneous detection of two MRSA specific genes (mecA and femA) amplified from genomic DNA isolated from clinical specimens. Magnetic isolation and rapid duplex detection were performed to obtain a detectable signal down to 104 input copies within 80 min. This demonstrated the potential of the SERS-PCR based approach for the accurate identification of MRSA at an early-diagnosis stage. This study also provides an alternative approach to the existing methods for detecting clinical targets without compromising sensitivity and selectivity, and with minimal handling steps. We thus believe that this approach will find a broad application in clinical applications.


Assuntos
DNA Bacteriano/análise , Staphylococcus aureus Resistente à Meticilina/genética , Análise Espectral Raman/métodos , Proteínas de Bactérias/genética , DNA Bacteriano/isolamento & purificação , DNA Bacteriano/metabolismo , Ouro/química , Magnetismo , Nanopartículas Metálicas/química , Proteínas de Ligação às Penicilinas/genética , Reação em Cadeia da Polimerase
11.
Inflamm Res ; 68(8): 691-704, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31147743

RESUMO

OBJECTIVE AND DESIGN: Inflammatory bowel disease (IBD) is known to cause chronic inflammation in the digestive tract by the immune malfunction. Herein, we demonstrate the protective effect of galangin (GAL), a phytochemical, on LPS-induced inflammation in cultured mouse macrophages (RAW 264.7) and the treatment of DSS-induced ulcerative colitis in Balb/c mice. However, the anti-inflammatory effect of GAL in DSS-exposed experimental colitis has not been investigated. MATERIALS AND METHODS: We determined the levels of proinflammatory cytokines by ELISA, biochemical analysis using standard protocols and protein expression level of NF-κB signaling pathway and activation of Nrf2 gene pathway were analyzed by western blot analysis in colitis-induced mice. RESULTS: Our in vitro studies showed that LPS-stimulated RAW 264.7 cells treated with GAL reduced the levels of nitrites, IL-6, and TNF-α in a concentration-dependent manner. The results demonstrated that oral administration of GAL at 20 mg/kg (lower dose) and 40 mg/kg (higher dose) significantly reduced the severity of colitis and mitigated the clinical signs of both macroscopic and microscopic of the disease. The levels of proinflammatory cytokines (TNF-α and IL-6) in colonic tissue and serum were reduced significantly and in GAL + DSS-treated group relative to DSS alone treated group.  Increased levels of anti-inflammatory cytokine (IL-10) was detected in colon tissues in GAL + DSS-treated groups relative to DSS alone treated group. We also observed decreased levels of myeloperoxidase (MPO), nitrites and TBARS with increased SOD in colonic tissue of GAL + DSS group. Besides, GAL + DSS-treated animals significantly suppressed protein expressions of p-NF-κB and p-Ikk-ßα, COX-2, iNOS, Nrf2 and increased HO-1 levels in colon tissues by inhibiting inflammation and oxidative stress. CONCLUSION: Our study highlights the protective effect of galangin as an anti-inflammatory agent against the severe form of colitis in pre-clinical models suggesting its potency for the treatment of IBD in humans.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Flavonoides/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/imunologia , Colite Ulcerativa/patologia , Colo/efeitos dos fármacos , Colo/imunologia , Colo/patologia , Citocinas/imunologia , Sulfato de Dextrana , Flavonoides/farmacologia , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos , Células RAW 264.7
12.
Mikrochim Acta ; 186(6): 346, 2019 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-31079205

RESUMO

The authors report on a simplified approach to encapsulate upconversion nanoparticles (UCNPs) in polystyrene spheres by mini-emulsion polymerisation. The resulting particles (PS-UCNP) are hydrophilic, stable and suitable for biomolecular recognition and biosensing applications. Also, a strategy was developed for bioconjugation of antibodies onto the surface of the PS-UCNPs by using the bifunctional fusion protein linker-protein G (LPG). LPG mediates the functionalisation of PS-UCNPs with antibodies against digoxigenin allowing for specific labelling of convective PCR (cPCR) amplicons. Lambda DNA was amplified using cPCR on a heat block for 30 min using the digoxigenin labelled forward and biotin labelled reverse primers. The antibody functionalised PS-UCNPs bind to the digoxigenin end of the cPCR amplicons. Finally, the streptavidin labelled magnetic beads were used to selectively capture the PS-UCNP-labelled cPCR amplicons and the upconversion signal was detected at 537 nm under 980 nm excitation. This sandwich approach enables direct recognition of the target lambda DNA with a detection limit of 103 copies µL-1. The upconversion signal decreased proportionally to the concentration of the lambda DNA with a linear response between 107 and 103 copies of DNA. Graphical abstract Schematic representation of polystyrene-encapsulated upconversion nanoparticles (PS-UCNPs) prepared by mini-emulsion polymerisation. The PS-UCNPs were functionalised with anti-digoxigenin antibody using the fusion protein linker-protein G (LPG). Detection of digoxigenin-labelled amplicons is achieved (a) by using the antibody-functionalised LPG@PS-UCNP labels; (b) magnetic separation, and (c) 980 nm laser light for detection of the green upconversion luminescence peaking at 537 nm.


Assuntos
Proteínas de Bactérias/química , Técnicas Biossensoriais/métodos , DNA Viral/análise , Nanopartículas/química , Poliestirenos/química , Animais , Anticorpos Imobilizados/imunologia , Bacteriófago lambda/química , Digoxigenina/imunologia , Érbio/química , Érbio/efeitos da radiação , Fluoretos/química , Fluoretos/efeitos da radiação , Separação Imunomagnética/métodos , Raios Infravermelhos , Limite de Detecção , Nanopartículas/efeitos da radiação , Reação em Cadeia da Polimerase/métodos , Ovinos , Ítrio/química , Ítrio/efeitos da radiação
13.
Bioorg Med Chem ; 26(13): 3837-3844, 2018 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-29983285

RESUMO

Malaria, particularly in endemic countries remains a threat to the human health and is the leading the cause of mortality in the tropical and sub-tropical areas. Herein, we explored new C2 symmetric hydroxyethylamine analogs as the potential inhibitors of Plasmodium falciparum (P. falciparum; 3D7) in in-vitro cultures. All the listed compounds were also evaluated against crucial drug targets, plasmepsin II (Plm II) and IV (Plm IV), enzymes found in the digestive vacuole of the P. falciparum. Analog 10f showed inhibitory activities against both the enzymes Plm II and Plm IV (Ki, 1.93 ±â€¯0.29 µM for Plm II; Ki, 1.99 ±â€¯0.05 µM for Plm IV). Among all these analogs, compounds 10g selectively inhibited the activity of Plm IV (Ki, 0.84 ±â€¯0.08 µM). In the in vitro screening assay, the growth inhibition of P. falciparum by both the analogs (IC50, 2.27 ±â€¯0.95 µM for 10f; IC50, 3.11 ±â€¯0.65 µM for 10g) displayed marked killing effect. A significant growth inhibition of the P. falciparum was displayed by analog 12c with IC50 value of 1.35 ±â€¯0.85 µM, however, it did not show inhibitory activity against either Plms. The hemolytic assay suggested that the active compounds selectively inhibit the growth of the parasite. Further, potent analogs (10f and 12c) were evaluated for their cytotoxicity towards mammalian HepG2 and vero cells. The selectivity index (SI) values were noticed greater than 10 for both the analogs that suggested their poor toxicity. The present study indicates these analogs as putative lead structures and could serve as crucial for the development of new drug molecules.


Assuntos
Antimaláricos/síntese química , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Etilaminas/química , Animais , Antimaláricos/metabolismo , Antimaláricos/farmacologia , Ácido Aspártico Endopeptidases/metabolismo , Sítios de Ligação , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Desenho de Fármacos , Etilaminas/metabolismo , Etilaminas/farmacologia , Células Hep G2 , Humanos , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/enzimologia , Estrutura Terciária de Proteína , Relação Estrutura-Atividade , Células Vero
14.
Can J Physiol Pharmacol ; 96(11): 1145-1152, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30075085

RESUMO

The rate at which Plasmodium falciparum is developing resistance to clinically used antimalarial drugs is alarming. Therefore, there is a compelling need to develop an efficient drug delivery system to improve the efficacy of existing antimalarial agents and circumvent drug resistance. Here, we report the antibacterial drug doxycycline (DOXY) in liposomal formulations exhibits enhanced antiplasmodial activity against blood stage forms of P. falciparum (3D7) in culture and established Plasmodium berghei NK-65 infection in murine model. Parasite killing on blood stage forms in culture was determined by a radiolabeled [3H] hypoxanthine incorporation assay and infected erythrocytes stained with Giemsa were counted using microscopy in vivo. The 50% inhibitory concentration (IC50) of DOXY-stearylamine liposome (IC50 0.36 µM) and DOXY-SPC:Chol-liposome (IC50 0.85 µM) exhibited marked growth inhibition of parasites compared with free DOXY (IC50 14 µM), with minimal toxicity to normal erythrocytes. Administration of polyethylene glycol distearoyl phosphatidylethanolamine-methoxy-polyethylene glycol2000 (DSPE-mPEG-2000) coated liposomes loaded with DOXY at 2.5 mg/kg per day resulted in efficacious killing of blood parasites with improved survival in mice relative to the free drug in both chloroquine sensitive and resistant strains of P. berghei infection. This is the first report to demonstrate that DOXY in liposomal system has immense chemotherapeutic potential against plasmodial infections at lower dosages.


Assuntos
Antimaláricos/administração & dosagem , Doxiciclina/administração & dosagem , Portadores de Fármacos/química , Malária/tratamento farmacológico , Plasmodium berghei/patogenicidade , Plasmodium falciparum/efeitos dos fármacos , Animais , Antimaláricos/uso terapêutico , Cloroquina/administração & dosagem , Cloroquina/uso terapêutico , Modelos Animais de Doenças , Doxiciclina/uso terapêutico , Resistência a Medicamentos , Eritrócitos/efeitos dos fármacos , Eritrócitos/parasitologia , Feminino , Humanos , Concentração Inibidora 50 , Lipossomos , Malária/parasitologia , Malária/patologia , Camundongos , Fosfatidiletanolaminas/química , Plasmodium berghei/efeitos dos fármacos , Polietilenoglicóis/química , Resultado do Tratamento
15.
Molecules ; 23(5)2018 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-29757989

RESUMO

A new class of compounds comprising two series of chalcones with 2,2,2-trifluoroethoxy group and 2-fluoroethoxy groups were synthesized and screened for in vitro antiplasmodial activity against Plasmodium falciparum (3D7) using the [³H] hypoxanthine incorporation inhibition assay. Chalcones with 2,2,2-trifluoroethoxy groups substituted on the p- and m-positions of the 1-phenyl ring showed weak antiplasmodial activity, while compounds substituted on the o-position of the 1-phenyl ring displayed enhanced antiplasmodial activity, thus indicating that 2,2,2-trifluoroethoxy groups on the 1-phenyl ring of chalcones show position-dependent antiplasmodial activity. Of the 34 compounds synthesized, chalcones 3a and 3f exhibited significant inhibitory effects, with IC50 values of 3.0 µg/mL and 2.2 µg/mL, respectively. Moreover, these compounds 3a and 3f showed profound antiplasmodial activity in combination with artemisinin in vitro. The most active molecules, 3a, and 3f, were further assessed for their cytotoxicity towards mammalian Vero cells and the selectivity index (SI) values are 8.6, and 8.2 respectively, being considered non-toxic. We also studied the antiplasmodial activity of 2-fluoroethoxychalcones to discern the effect of the number of fluorine atoms in the fluoroethoxy group. Our results showed that chalcones with 2-fluoroethoxy group on the 1-phenyl ring exhibited more enhanced inhibitory effects on the growth of parasites than their trifluoro analogues, which reveals that monofluoroethoxy group is generally more effective than trifluoroethoxy group in the inhibition of parasite growth. Thus o-2,2,2-trifluoroethoxychalcones (Series 3) and 2-fluoroethoxychalcones may serve as good antiplasmodial candidates for future further development.


Assuntos
Antimaláricos/síntese química , Antimaláricos/farmacologia , Chalconas/síntese química , Chalconas/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Animais , Antimaláricos/química , Chalconas/química , Técnicas de Química Sintética , Chlorocebus aethiops , Eritrócitos/efeitos dos fármacos , Eritrócitos/parasitologia , Concentração Inibidora 50 , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Testes de Sensibilidade Parasitária , Células Vero
16.
Antimicrob Agents Chemother ; 60(3): 1304-18, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26666937

RESUMO

The global emergence of drug resistance in malaria is impeding the therapeutic efficacy of existing antimalarial drugs. Therefore, there is a critical need to develop an efficient drug delivery system to circumvent drug resistance. The anticoccidial drug monensin, a carboxylic ionophore, has been shown to have antimalarial properties. Here, we developed a liposome-based drug delivery of monensin and evaluated its antimalarial activity in lipid formulations of soya phosphatidylcholine (SPC) cholesterol (Chol) containing either stearylamine (SA) or phosphatidic acid (PA) and different densities of distearoyl phosphatidylethanolamine-methoxy-polyethylene glycol 2000 (DSPE-mPEG-2000). These formulations were found to be more effective than a comparable dose of free monensin in Plasmodium falciparum (3D7) cultures and established mice models of Plasmodium berghei strains NK65 and ANKA. Parasite killing was determined by a radiolabeled [(3)H]hypoxanthine incorporation assay (in vitro) and microscopic counting of Giemsa-stained infected erythrocytes (in vivo). The enhancement of antimalarial activity was dependent on the liposomal lipid composition and preferential uptake by infected red blood cells (RBCs). The antiplasmodial activity of monensin in SA liposome (50% inhibitory concentration [IC50], 0.74 nM) and SPC:Chol-liposome with 5 mol% DSPE-mPEG 2000 (IC50, 0.39 nM) was superior to that of free monensin (IC50, 3.17 nM), without causing hemolysis of erythrocytes. Liposomes exhibited a spherical shape, with sizes ranging from 90 to 120 nm, as measured by dynamic light scattering and high-resolution electron microscopy. Monensin in long-circulating liposomes of stearylamine with 5 mol% DSPE-mPEG 2000 in combination with free artemisinin resulted in enhanced killing of parasites, prevented parasite recrudescence, and improved survival. This is the first report to demonstrate that monensin in PEGylated stearylamine (SA) liposome has therapeutic potential against malaria infections.


Assuntos
Antimaláricos/farmacologia , Artemisininas/farmacologia , Lipossomos/administração & dosagem , Malária/tratamento farmacológico , Monensin/farmacologia , Aminas/administração & dosagem , Aminas/química , Animais , Antimaláricos/administração & dosagem , Sangue/efeitos dos fármacos , Sangue/parasitologia , Sistemas de Liberação de Medicamentos/métodos , Quimioterapia Combinada , Feminino , Lipossomos/química , Lipossomos/farmacologia , Malária/parasitologia , Camundongos , Monensin/farmacocinética , Plasmodium berghei/patogenicidade , Plasmodium falciparum/efeitos dos fármacos , Distribuição Tecidual
17.
Bioorg Med Chem ; 23(8): 1817-27, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25766631

RESUMO

Phthalimides functionalized with cyclic amines were synthesized, characterized and screened for their in vitro antimalarial efficacy against Plasmodium falciparum (Pf3D7). Of all the listed phthalimides evaluated, 14 and 24 were identified as potent antimalarial agents as advocated by assessment of their ability to inhibit [(3)H] hypoxanthine incorporation in the nucleic acid of parasites. In addition, phthalimides 14 and 24 were incubated for 60 and 90h and an enhanced antimalarial effect was noticed with increase in time to great extent. A reduction in IC50 values was observed with increase in exposure time of the parasite to the compounds. A symmetric phthalimide, 24 possessing piperazine as linker unit was identified as the most potent antimalarial agent with IC50 values of 5.97±0.78, 2.0±1.09 and 1.1±0.75µM on incubation period of 42, 60 and 90h, respectively. The abnormal morphologies such as delay in developmental stages, growth arrest and condensed nuclei of parasite were observed with the aid of microscopic studies upon exposure with 14 and 24. The evaluation of 14 and 24 against chloroquine resistant strain, (Pf7GB) of P. falciparum afforded IC50 values, 13.29±1.20 and 7.21±0.98µM, respectively. The combination of 24 with artemisinin (ART) showed enhanced killing of parasite against Pf3D7. Further, all phthalimides were evaluated for their activity against falcipain-2 (FP2), a major hemoglobinase of malarial parasite. The enzymatic assay afforded 6 as most active member against FP2. To the best of our knowledge this is the initial study represents phthalimide protected amino acids functionalized with cyclic amines as potent antimalarial agents.


Assuntos
Antimaláricos/química , Antimaláricos/farmacologia , Cisteína Endopeptidases/metabolismo , Ftalimidas/química , Ftalimidas/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Antimaláricos/síntese química , Humanos , Malária Falciparum/tratamento farmacológico , Malária Falciparum/microbiologia , Simulação de Acoplamento Molecular , Ftalimidas/síntese química , Piperazinas/síntese química , Piperazinas/química , Piperazinas/farmacologia , Plasmodium falciparum/metabolismo
18.
Cureus ; 16(2): e53738, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38465180

RESUMO

In India, the COVID-19 vaccination for adolescents aged 15-17 years has been started since January 2022. Gluten enteropathy, also known as celiac or nontropical sprue, can arise as an autoimmune disease of the small intestines. We report a 15-year-old female with a history of allergy to gluten-containing products who came for the first dose of the COVID-19 vaccination to adult vaccination OPD at All India Institute of Medical Sciences, Jodhpur. After taking a detailed history, she had an allergy to gluten-containing products for five years. She had no previous history of allergic reactions to injections or medicines. The first dose of Covaxin was given to this female under proper supervision, and she was followed up for any adverse events. We did not find any evidence of adverse events following the COVID-19 vaccination in people with gluten enteropathy. The patient was discharged after one hour of observation. To date, no cases of Covaxin vaccination have been reported among gluten enteropathy patients. We discuss the current evidence relating to Covaxin vaccinations, highlighting that administering the vaccine to gluten-sensitive individuals did not cause any adverse reactions. However, proper history taking and other standard procedures should be followed while administering Covaxin to any known allergies.

19.
Cureus ; 16(6): e62129, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38993421

RESUMO

Background and objectives Considering the increasing utilization of online educational tools in medical education, it is essential to evaluate the reliability and validity of online assessments to accurately assess student proficiency and predict academic success. This study investigated the predictive efficacy of different online assessment methods in comparison to standard offline methods within the medical educational setting. Methods This study utilized a mixed-methods crossover design, involving 125 first-year medical students who were randomly assigned to either online or traditional examinations. The students then crossed over to the other type of assessment. The assessments consisted of multiple-choice questions (MCQs), viva voce, objective structured clinical examinations, and written theory examinations. Quantitative data on results, finishing times, and academic metrics were analyzed, along with qualitative data from student interviews exploring perceptions of each format. Results The online MCQs had the highest average scores and a moderately positive correlation with performance on the theory examination (r=0.326). Regression models indicated that online and offline MCQs were moderate positive predictors of theoretical marks (R2=0.106 and 0.107, respectively). Qualitative responses emphasized advantages such as flexibility and accessibility for online examinations but also concerns regarding technological challenges, interaction, and integrity compared to traditional formats. Conclusions Online MCQ assessments showed promise as indicators of medical student academic performance. However, additional online forms require improvement to match conventional assessments reliably. As medical education involves digital technologies, cautious implementation of online evaluations substantiated by further research is needed to preserve educational quality standards.

20.
J Hosp Infect ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39032571

RESUMO

BACKGROUND: Despite global recognition, WHO reports reveal significant gaps, with one in four healthcare facilities lacking basic water services, affecting over 1.8 billion people, and 21% lacking sanitation services, impacting 1.5 billion people, especially prevalent in low- and middle-income countries (LMICs). This study aimed to critically evaluate the current state of WASH facilities across a diverse range of healthcare settings. METHODS: This review includes various databases such as PubMed, MEDLINE, EMBASE, CINAHL, Scopus, and grey literature, eligible studies employing various designs were scrutinized for WASH infrastructure and practices. Methodological quality was rigorously evaluated using the QuADS checklist. Data analysis, performed with R software, involved deriving pooled estimates of WASH intervention effects. Sensitivity analyses were conducted, employing statistical methods like funnel plots to ensure robustness and mitigate biases. RESULTS: Out of 13,250 articles screened, 18 were included in this review. Meta-analyses revealed significant effect sizes for WASH interventions across domains- water (67.38%), sanitation (53.93%), waste management (40.82%), environment (56.58%), hygiene (66.83%), and management (42.30%). CONCLUSION: Widespread disparities in Water, Sanitation, and Hygiene (WASH) persist across healthcare facilities (HCFs), with rural areas facing notable deficits. Challenges in water quality, sanitation, and waste management demand comprehensive, multi-sectoral approaches for improvement.

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