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1.
Molecules ; 27(4)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35209008

RESUMO

A South African traditional formulation, PHELA®, is consumed by the traditional people for severe chest problems with coughing, diarrhea, oral ulcers etc. The present study focused on establishing the anti-infective properties of a safe and standardized poly-herbal formulation through a series of criteria and specifications.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Medicinas Tradicionais Africanas , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Anti-Infecciosos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Humanos , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Extratos Vegetais/isolamento & purificação
2.
Molecules ; 27(11)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35684442

RESUMO

Background: This study comparatively assessed seven indigenous traditional tea plants on several attributes that included antioxidant, nutritional, caffeine contents, and cyclooxygenase activity. Methodology: Nutritional content of all tea plants were determined for energy, fat, carbohydrates, total sugars, dietary fiber and amino acids. Antioxidant potential and the antioxidant potentiating secondary metabolites were also measured and compared. Further, we investigated the tea plants for any role they would have on cyclooxygenase (COX) activity on cobalt chloride (CoCl2) induced human glioma cell lines (U87MG). Results: The tea plants were found non-cytotoxic at concentrations tested against the human Chang liver and HeK 293 kidney cells and were found to be naturally caffeine free. The lowest and highest extraction yield among the tea plants was 7.1% for B. saligna and 15.48% for L. scaberrimma respectively. On average, the flavonol content was 12 to 8 QE/g, ORAC 800 µmol TE/g, TEAC 150 µmol TE/g, FRAP 155 µmol AAE/g, polyphenols 40 mg GAE/g, flavanols 0.35 mg CE/g, flavonols 12 mg QE/g and total flavonoid content (TFC) 180 µg QE/mg. The COX activity has been found to be inhibited by a dose-dependent manner by L. scaberrimma, B. saligna and L. javanica. Conclusion: The results further support competitive value of tea plants and need for improved and further development.


Assuntos
Antioxidantes , Chás de Ervas , Antioxidantes/química , Cafeína , Hipóxia Celular , Inibidores de Ciclo-Oxigenase , Flavonóis , Células HEK293 , Humanos , Valor Nutritivo , Polifenóis/química , Prostaglandina-Endoperóxido Sintases , África do Sul
3.
Cytokine ; 144: 155555, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33992538

RESUMO

Emergence and spread of resistant parasites to the newest chemotherapeutic anti-malarial agents are the biggest challenges against malaria control programs. Therefore, developing a novel effective treatment to reduce the overgrowing burden of multidrug resistant malaria is a pressing need. Herein, we have developed a biocompatible and biodegradable, non-toxic chitosan-tripolyphosphate-chloroquine (CS-TPP CQ) nanoparticle. CS-TPP CQ nanoparticles effectively kill the parasite through redox generation and induction of the pro- and anti-inflammatory cytokines in both sensitive and resistant parasite in vitro. The in vitro observations showed a strong inhibitory effect (p < 0.01) on pro-inflammatory cytokines more specifically on TNF-α and IFN-γ whereas CS-TPP CQ nanoparticles significantly elevated the anti-inflammatory cytokines- IL-10 and TGF-ß. In addition, CS-TPP CQ nanoparticle significantly increased NO generation (p < 0.01) and altered the GSH/GSSG ratio 72 h after parasite co-culture with peripheral blood mononuclear cells culminating in the free radical induced parasite killing. CS-TPP CQ nanoparticle had an effective dose of 100 ng/ml against CQ-sensitive parasite lines (p < 0.001) whereas effective dose against CQ-resistant parasite line was 200 ng/ml CS-TPP CQ with an effective duration of 72 h (p < 0.001). Our studies suggest that CS-TPP CQ nanoparticle has a potential to modulate the pro- and anti-inflammatory responses, and to trigger the redox-mediated parasite killing. It can be a novel nano-based futuristic approach towards malaria control.


Assuntos
Antimaláricos/farmacologia , Citocinas/metabolismo , Malária/tratamento farmacológico , Nanopartículas/administração & dosagem , Oxirredução/efeitos dos fármacos , Parasitos/efeitos dos fármacos , Animais , Células Cultivadas , Quitosana/administração & dosagem , Quitosana/análogos & derivados , Cloroquina/farmacologia , Resistência a Medicamentos/efeitos dos fármacos , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Leucócitos Mononucleares/metabolismo , Malária/metabolismo , Parasitos/metabolismo , Plasmodium falciparum/efeitos dos fármacos
4.
J Biol Inorg Chem ; 22(6): 893-918, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28643149

RESUMO

Currently toxicological research in Silver nanoparticle is a leading issue in medical science. The surface chemistry and physical dimensions of silver nanoparticles (Ag-NPs) play an important role in toxicity. The aim of this present study was to evaluate the in vitro and in vivo toxicity of Ag-NPs as well as the alteration of toxicity profile due to surface functionalization (PEG and BSA) and the intracellular signaling pathways involved in nanoparticles mediated oxidative stress and apoptosis in vitro and in vivo system. Ag-NPs released excess Ag+ ions leads to activation of NADPH oxidase and helps in generating the reactive oxygen species (ROS). Silver nanoparticles elicit the production of excess amount of ROS results activation of TNF-α. Ag-NPs activates caspase-3 and 9 which are the signature of mitochondrial pathway. Ag-NPs are responsible to decrease the antioxidant enzymes and imbalance the oxidative status into the cells but functionalization with BSA and PEG helps to protect the adverse effect of Ag-NPs on the cells. This study suggested that Ag-NPs are toxic to normal cells which directly lead with human health. Surface functionalization may open the gateway for further use of Ag-NPs in different area such as antimicrobial and anticancer therapy, industrial use or in biomedical sciences.


Assuntos
Nanopartículas Metálicas/toxicidade , Prata/química , Prata/toxicidade , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Biomarcadores/metabolismo , Peso Corporal/efeitos dos fármacos , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Hemólise/efeitos dos fármacos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Polietilenoglicóis/química , Soroalbumina Bovina/química , Relação Estrutura-Atividade , Propriedades de Superfície
5.
Nanotechnology ; 28(9): 095102, 2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-28139466

RESUMO

Drug-resistant bacteria are an increasingly serious threat to global public health. In particular, infections from multidrug-resistant (MDR) Gram-positive bacteria (i.e. Staphylococcus aureus) are growing global health concerns. In this work, we report the first use of nanoscale metal-organic frameworks (NMOFs) coencapsulating an antibiotic (vancomycin) and targeting ligand (folic acid) in one pot to enhance therapeutic efficacy against MDR S. aureus. Zeolitic imidazolate framework (ZIF-8) NMOFs, which have globular morphologies coencapsulating vancomycin and folic acid, are characterized by transmission electron microscopy, field-emission scanning electron microscopy, powder x-ray diffraction, ulltraviolet-visible spectroscopy, and dynamic light-scattering techniques. We determined that the presence of folic acid on the surface of the NMOFs is significant in the sense of effective uptake by MDR S. aureus through endocytosis. The functionalized NMOFs transport vancomycin across the cell wall of MDR S. aureus and enhance antibacterial activity, which has been confirmed from studies of the minimum inhibitory concentration, minimum bactericidal concentration, cytotoxicity of bacterial cells, and generation of reactive oxygen species. This work shows that functionalized NMOFs hold great promise for effective treatment of MDR S. aureus.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Estruturas Metalorgânicas/síntese química , Nanopartículas/química , Staphylococcus aureus/efeitos dos fármacos , Difusão Dinâmica da Luz , Escherichia coli/efeitos dos fármacos , Escherichia coli/ultraestrutura , Ácido Fólico/farmacologia , Espaço Intracelular/metabolismo , Luminescência , Estruturas Metalorgânicas/química , Viabilidade Microbiana/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/citologia , Staphylococcus aureus/ultraestrutura , Vancomicina/farmacologia , Difração de Raios X
6.
J Biol Inorg Chem ; 20(1): 123-141, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25534662

RESUMO

The aim of this work is to understand the potential health effects of metal nanoparticles by exposing human leukemic cell lines (jurkat, K562 and KG1A cells) to nanosize phosphonomethyl iminodiacetic acid coated cobalt oxide (PMIDA-CoO) NPs. The synthesized PMIDA-CoO NPs were characterized by XRD, dynamic light scattering, transmission electron microscopy and scanning electron microscopy. Our results showed that exposure of leukemic cell lines to PMIDA-CoO NPs caused reactive oxygen species (ROS) generation by increasing the concentration of free Co(++) ions in cancer microenvironment. But at physiological pH, PMIDA-CoO liberates little amount of Co(++) ions into media and exerts lower toxicity to normal cells up to a certain dose. PMIDA-CoO NPs caused DNA damage in leukemic cell lines, which was reflected by an increase in apoptosis of jurkat, KG-1A and K562 cells. PMIDA-CoO NPs induced apoptosis by increasing pro-inflammatory cytokines, primarily TNF-α. The in vivo study shows that PMIDA-CoO NPs were efficiently killed DLA cells. These findings have important implications for understanding the potential anticancer property induced by surface-modified cobalt oxide nanoparticles.


Assuntos
Antineoplásicos/farmacologia , Cobalto/farmacologia , Iminoácidos/farmacologia , Sistema de Sinalização das MAP Quinases , Nanopartículas , Óxidos/farmacologia , Animais , Antineoplásicos/química , Caspase 3/metabolismo , Caspase 8/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Cobalto/química , Citocinas/metabolismo , Fragmentação do DNA , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Iminoácidos/química , Células Jurkat , Células K562 , Leucemia/tratamento farmacológico , Linfoma/tratamento farmacológico , Camundongos , Estresse Oxidativo , Óxidos/química , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
7.
Bioorg Chem ; 63: 85-100, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26469741

RESUMO

The main complication in betulinic acid (BA) based drug delivery has been observed due to its bulk structure. The present study demonstrates the potential effects of self assembled nano size betulinic acid (SA-BA) by treating human leukemic cell lines (KG-1A and K562) and its normal counterpart. Self assembly property of BA was investigated using SEM and DLS study which showed that the BA forms fibrous structure having few nanometers in diameter. Selective anti-leukemic efficacy study of SA-BA was investigated by cell viability assay. Mode of leukemic cell death and probable pathway of apoptosis was monitored by measuring ROS level, pro and anti-inflammatory cytokine status and expression of caspase-8 and caspage-3 by immunocytochemistry. Higher efficacy of SA-BA over non-assemble BA was monitored toward cancer cells, with no relevant toxicity to normal blood cells. SA-BA facilitated reactive oxygen species (ROS) mediated leukemic cell death, confirmed by pre-treatment of N-acetyl-L-cysteine. Induction of apoptosis by SA-BA treatment increased pro-inflammatory cytokines, specifically potentiated TNF-α mediated cell death, confirmed by expression of caspase-8 and caspage-3 by immunocytochemistry. This study explored the better anti-leukemic efficacy of SA-BA over BA and this modification will enrich the use of BA in cancer therapy.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Leucemia/patologia , Nanofibras/química , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Triterpenos/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células K562 , Estrutura Molecular , Triterpenos Pentacíclicos , Relação Estrutura-Atividade , Triterpenos/síntese química , Triterpenos/química , Ácido Betulínico
8.
J Appl Toxicol ; 35(6): 603-13, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25639670

RESUMO

The purpose of this study was to determine the intracellular signaling transduction pathways involved in oxidative stress induced by nanoparticles in cancer cells. Activation of reactive oxygen species (ROS) has some therapeutic benefits in arresting the growth of cancer cells. Cobalt oxide nanoparticles (CoO NPs) are an interesting compound for oxidative cancer therapy. Our results showed that CoO NPs elicited a significant (P <0.05) amount of ROS in cancer cells. Co-treatment with N-aceyltine cystine (an inhibitor of ROS) had a protective role in cancer cell death induced by CoO NPs. In cultured cells, the elevated level of tumor necrosis factor-alpha (TNF-α) was noted after CoO NPs treatment. This TNF-α persuaded activation of caspase-8 followed by phosphorylation of p38 mitogen-activated protein kinase and induced cell death. This study showed that CoO NPs induced oxidative stress and activated the signaling pathway of TNF-α-Caspase-8-p38-Caspase-3 to cancer cells.


Assuntos
Caspase 8/fisiologia , Cobalto/efeitos adversos , Leucemia Experimental/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Nanopartículas Metálicas/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Óxidos/efeitos adversos , Fator de Necrose Tumoral alfa/fisiologia , Acetilcisteína/farmacologia , Animais , Apoptose/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Microscopia Eletrônica de Transmissão , Transplante de Neoplasias , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
9.
J Basic Microbiol ; 55(9): 1053-63, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25740654

RESUMO

Plasmodium parasites, which is responsible to cause malaria, are also exceedingly receptive to oxidative stress during their intraerythrocytic life stage as they devour haemoglobin inside their food vacuoles and engender toxic haem moieties and reactive oxygen species (ROS). Other than, several studies suggest that the generation of reactive oxygen and nitrogen species (ROS and RNS) associated with oxidative stress, plays a decisive role in the ripeness of systemic complications caused by malaria. Malaria infection provokes the generation of hydroxyl radicals (OH(•)), which most probably is the main reason for the induction of oxidative stress and apoptosis. In this study, it has been described to understand how redox molecules and NO carry out their diverse functions in both parasites and host. It is very important to understand the chemical reactions that produce those outcomes and how its regulation carried out by parasite during erythrocytic phase.


Assuntos
Plasmodium/metabolismo , Transdução de Sinais , Vertebrados/parasitologia , Animais , Humanos , Malária/metabolismo , Óxido Nítrico/metabolismo , Oxirredução , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Vertebrados/imunologia , Vertebrados/metabolismo
10.
Antimicrob Agents Chemother ; 58(10): 5909-15, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25070111

RESUMO

Malaria is a major public health problem in tropical and subtropical countries, including India. This study elucidates the cause of chloroquine treatment failure (for Plasmodium falciparum infection) before the introduction of artemisinin combination therapy. One hundred twenty-six patients were randomized to chloroquine treatment, and the therapeutic efficacy was monitored from days 1 to 28. An in vitro susceptibility test was performed with all isolates. Parasitic DNA was isolated, followed by PCR and restriction digestion of different codons of the pfcrt gene (codons 72 to 76) and the pfmdr1 gene (N86Y, Y184F, S1034C, N1042D, and D1246Y). Finally, sequencing was done to confirm the mutations. Forty-three (34.13%) early treatment failure cases and 16 (12.69%) late treatment failure cases were observed after chloroquine treatment. In vitro chloroquine resistance was found in 103 isolates (81.75%). Twenty-six (60.47%) early treatment failure cases and 6 (37.5%) late treatment failure cases were associated with the CVMNK-YYSNY allele (the underlined amino acids are those that were mutated). Moreover, the CVIEK-YYSNY allele was found in 8 early treatment failure (18.60%) and 2 late treatment failure (12.5%) cases. The presence of the wild-type pfcrt (CVMNK) and pfmdr1 (YYSNY) double mutant allele in chloroquine-nonresponsive cases was quite uncommon. In vivo chloroquine treatment failure and in vitro chloroquine resistance were strongly correlated with the CVMNK-YYSNY and CVIEK-YYSNY haplotypes (P < 0.01).


Assuntos
Antimaláricos/uso terapêutico , Cloroquina/uso terapêutico , Resistência a Medicamentos/genética , Malária Falciparum/tratamento farmacológico , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Humanos , Índia , Malária Falciparum/genética , Mutação , Plasmodium falciparum/patogenicidade
11.
J Biol Inorg Chem ; 19(3): 399-414, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24445996

RESUMO

The objective of this study was to develop chitosan-based delivery of cobalt oxide nanoparticles to human leukemic cells and investigate their specific induction of apoptosis. The physicochemical properties of the chitosan-coated cobalt oxide nanoparticles were characterized using transmission electron microscopy, dynamic light scattering, X-ray diffraction, and Fourier transform infrared spectroscopy. The solubility of chitosan-coated cobalt oxide nanoparticles was higher at acidic pH, which helps to release more cobalt ions into the medium. Chitosan-coated cobalt oxide nanoparticles showed good compatibility with normal cells. However, our results showed that exposure of leukemic cells (Jurkat cells) to chitosan-coated cobalt oxide nanoparticles caused an increase in reactive oxygen species generation that was abolished by pretreatment of cells with the reactive oxygen species scavenger N-acetyl-L-cysteine. The apoptosis of Jurkat cells was confirmed by flow-cytometric analysis. Induction of TNF-α secretion was observed from stimulation of Jurkat cells with chitosan-coated cobalt oxide nanoparticles. We also tested the role of TNF-α in the induction of Jurkat cell death in the presence of TNF-α and caspase inhibitors. Treatment of leukemic cells with a blocker had a greater effect on cancer cell viability. From our findings, oxidative stress and caspase activation are involved in cancer cell death induced by chitosan-coated cobalt oxide nanoparticles.


Assuntos
Apoptose/fisiologia , Quitosana/química , Cobalto/química , Leucemia de Células T/metabolismo , Nanopartículas Metálicas/química , Óxidos/química , Fator de Necrose Tumoral alfa/fisiologia , Apoptose/efeitos dos fármacos , Quitosana/farmacologia , Quitosana/uso terapêutico , Cobalto/farmacologia , Cobalto/uso terapêutico , Relação Dose-Resposta a Droga , Humanos , Células Jurkat , Leucemia de Células T/tratamento farmacológico , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Óxidos/farmacologia , Óxidos/uso terapêutico , Fator de Necrose Tumoral alfa/farmacologia , Difração de Raios X
12.
J Biol Inorg Chem ; 18(8): 957-73, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24043470

RESUMO

The purpose of this study is to evaluate the prospect of using surface modified cobalt oxide(CoO) nanoparticles as carriers of cancerantigens to human macrophages. N-Phosnomethyliminodiacetic acid (PMIDA) was used for surface modification to overcome the toxic effect of CoO nanoparticles. Here, the phosphonate group of the PMIDA acts as a surface-anchoring agent and the remaining -COOH groups bind nonspecifically with tumor associated antigens. This modification allows the conjugation of human oral carcinoma (KB) cell lysate (CL) as an antigen with PMIDA coated CoO nanoparticles (CL-PMIDA-CoO). Particle characterization was performed by dynamic light scattering, atomic force microscopy, and scanning electron microscopy studies. Fourier transform IR spectroscopy was used to investigate conjugation of the protein with nanoparticles. Protein encapsulation was confirmed by protein gel electrophoresis. Active uptake of antigen-conjugated nanoparticles by macrophages was confirmed by fluorescence microscopy. The antitumor activity of the nanocomplex pulsed macrophages was investigated on a human oral carcinoma cell line (KB) in vitro. The modified nanocomplexes upregulate IFN-γ and TNF-α and induce an anticancer immune response by activating macrophages. The use of TNF-α inhibitor confirmed the ability of the CL-PMIDA-CoO nanocomplex to stimulate TNF-α mediated immunostimulation. CL-PMIDA-CoO nanoparticles efficiently increased the CD4(+) population. Thus, our findings provide insight into the use of PMIDA coated CoO nanoparticles as antigen delivery vehicles.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Antígenos de Neoplasias/administração & dosagem , Antineoplásicos/administração & dosagem , Cobalto/química , Portadores de Fármacos/química , Neoplasias Bucais/terapia , Nanopartículas/química , Óxidos/química , Adjuvantes Imunológicos/farmacologia , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/farmacologia , Antineoplásicos/imunologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Células Cultivadas , Humanos , Iminoácidos/química , Imunoterapia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/patologia , Neoplasias Bucais/imunologia , Fator de Necrose Tumoral alfa/imunologia
13.
Biomed Mater ; 18(6)2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37827172

RESUMO

Recently, photodynamic therapy (PDT) has received a lot of attention for its potential use in cancer treatment. It enables the therapy of a multifocal disease with the least amount of tissue damage. The most widely used prodrug is 5-aminolevulinic acid, which undergoes heme pathway conversion to protoporphyrin IX, which acts as a photosensitizer (PS). Additionally, hematoporphyrin, bacteriochlorin, and phthalocyanine are also studied for their therapeutic potential in cancer. Unfortunately, not every patient who receives PDT experiences a full recovery. Resistance to different anticancer treatments is commonly observed. A few of the resistance mechanisms by which cancer cells escape therapeutics are genetic factors, drug-drug interactions, impaired DNA repair pathways, mutations related to inhibition of apoptosis, epigenetic pathways, etc. Recently, much research has been conducted to develop a new generation of PS based on nanomaterials that could be used to overcome cancer cells' multidrug resistance (MDR). Various metal-based, polymeric, lipidic nanoparticles (NPs), dendrimers, etc, have been utilized in the PDT application against cancer. This article discusses the detailed mechanism by which cancer cells evolve towards MDR as well as recent advances in PDT-based NPs for use against multidrug-resistant cancers.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico
14.
BMJ Glob Health ; 8(8)2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37558269

RESUMO

Management of COVID-19 in Africa is challenging due to limited resources, including the high cost of vaccines, diagnostics, medical devices and routine pharmaceuticals. These challenges, in addition to wide acceptability, have resulted in increased use of herbal medicines based on African traditional medicines (ATMs) by patients in Africa. This is in spite of the often-significant gaps in evidence regarding these traditional medicines as to their efficacy and safety for COVID-19. African scientists, with some support from their governments, and guidance from WHO and other bodies, are addressing this evidence gap, developing and testing herbal medicines based on ATMs to manage mild-to-moderate cases of COVID-19. Such efforts need further support to meet public health needs.


Assuntos
COVID-19 , Humanos , Medicinas Tradicionais Africanas , Pandemias , África , Extratos Vegetais
15.
Trop Med Int Health ; 17(11): 1329-34, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22909027

RESUMO

OBJECTIVE: To evaluate the anti-folate (sulphadoxine)-resistant pattern in Kolkata, one of the malaria endemic zones of Eastern India. METHODS: At first, 107 P. falciparum suspected cases were enrolled in this study. Ninety isolates (84.11%) of 107 suspected cases were analysed, as they had mono-infection with P. falciparum. In vitro susceptibility assays were performed in all 90 isolates. Parasitic DNA was isolated by phenol-chloroform extraction method and polymerase chain reaction was followed by restriction fragment length polymorphism analysis of different codons of the pfdhps gene (436, 437, 540, 581 and 613). RESULTS: Among 90 isolates from Kolkata, dhps mutant isolates at codons 436, 437, 540, 581 and 613 were found in 53.33%, 67.78%, 46.66%, 15.56% and 45.55%, respectively. In vitro sulphadoxine resistance was found in 49 isolates (54.44%). Interestingly we found 33 isolates (36.67%) with quadruple AGEAT mutant allele, of which 32 isolates (96.97%) were highly sulphadoxine resistant (P < 0.01) in vitro. CONCLUSION: Our present findings implicate that because of enormous drug (sulphfadoxine) pressure, novel AGEAT mutation was highly correlated (P < 0.01) with sulphadoxine resistance.


Assuntos
Di-Hidropteroato Sintase/genética , Malária Falciparum/genética , Mutação , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Antimaláricos/uso terapêutico , DNA de Protozoário/genética , Resistência a Medicamentos , Genótipo , Humanos , Índia , Malária Falciparum/tratamento farmacológico , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Sulfadoxina/uso terapêutico
16.
Toxicol Mech Methods ; 22(3): 193-204, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22074192

RESUMO

Staphylococcus aureus is most frequently isolated pathogen causing bloodstream infections, skin and soft tissue infections and pneumonia. Vancomycin sensitive and resistant S. aureus infection causes oxidative stress in neutrophils and lymphocytes. Lymphocyte is an important immune cell. The immune cells use reactive oxygen species (ROS) for carrying out their normal functions while an excess amount of ROS can attack cellular components that lead to cell damage. The aim of the present study was to test the protective role of nanoconjugated vancomycin against Vancomycin Sensitive S. aureus (VSSA) and Vancomycin Resistant S. aureus (VRSA) infection induced oxidative stress in T-lymphocytes. VSSA and VRSA infection were developed in Swiss mice by intraperitoneal injection of 5 × 10(6) CFU/ml bacterial solutions. Nanoconjugated vancomycin was treated to VSSA and VRSA infected mice at a dose of 100 mg/kg bw/day and 500 mg/kg bw/day, respectively for successive 10 days. Vancomycin was treated to VSSA and VRSA infected mice at similar dose, respectively, for 10 days. The result of this study reveals that in vivo VSSA and VRSA infection significantly increases the level of nitrite generation, lipid peroxidation, protein oxidation, oxidized glutathione level, DNA fragmentation, and decreases the level of reduced glutathione, antioxidant enzyme status, glutathione dependent enzymes as compared to control group; which were increased or decreased significantly near to normal in T-lymphocytes of nanoconjugated vancomycin treated group. These finding suggests the potential use and beneficial protective role of nanoconjugated vancomycin against VSSA and VRSA infection induced oxidative stress in T-lymphocytes.


Assuntos
Antibacterianos/farmacologia , Fragmentação do DNA , Nanoconjugados , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Resistência a Vancomicina , Vancomicina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Catalase/metabolismo , Química Farmacêutica , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Nitratos/metabolismo , Oxirredução , Carbonilação Proteica/efeitos dos fármacos , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Superóxido Dismutase/metabolismo , Linfócitos T/imunologia , Linfócitos T/microbiologia , Fatores de Tempo
17.
Aging Dis ; 13(1): 29-36, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35111360

RESUMO

Presently, the second wave of COVID-19 pandemic is driving the world towards a devastating total failure of the healthcare system. The purpose of the review is to search for the studies reporting on the implication of herd immunity into a naïve population through age specific mass vaccination. This review is based on selected publications on the effect herd immunity to COVID 19 in communities. We searched published scientific articles, review articles, reports, published in 2020 as well as read some basic, cult publications related to establishment of indirect immunity to a population. We have focused on use of application of vaccine induced herd immunity into community to confer indirect immunity against COVID-19 and searched on electronic databases, including PubMed (http://www.pubmed.com), Scopus (http://www.scopus.com), Google Scholar (http://www.scholar.google.com), Web of Science (www.webofscience.com) and Science Direct by using key words such as Herd immunity, indirect or passive immunization, Coronavirus disease 2019 (COVID-19), severe acute respiratory syndrome, coronavirus 2 (SARS-CoV-2), and immune-technique. This review proposes the implication of mass vaccination-induced herd immunity in a population to curb the infection, and to every individual in a given population irrespective of their age.

18.
Front Cell Infect Microbiol ; 12: 865814, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36583107

RESUMO

Introduction: After being used vigorously for the previous two decades to treat P. falciparum, chloroquine and sulfadoxine-pyrimethamine were replaced in 2009 with an artemisinin-based combination therapy (artesunate-sulfadoxine-pyrimethamine) in an effort to combat multidrug-resistant parasites. Methods: We set out to assess the genetic variants of sulfadoxine-pyrimethamine resistance and the effectiveness of its treatment in eastern India prior to, during, and 6 to 8 years following the introduction of the new pharmacological regime. In 2008-2009, 318 P. falciparum-positive patients got the recommended doses of sulfadoxine-pyrimethamine. We used 379 additional isolates from 2015 to 2017 in addition to the 106 isolates from 2010. All 803 isolates from two study sites underwent in vitro sulfadoxine-pyrimethamine sensitivity testing and genomic characterisation of sulfadoxine-pyrimethamine resistance (pfdhfr and pfdhps). Results: In Kolkata and Purulia, we observed early treatment failure in 30.7 and 14.4% of patients, respectively, whereas recrudescence was found in 8.1 and 13.4% of patients, respectively, in 2008-2009. In 2017, the proportion of in vitro pyrimethamine and sulfadoxine resistance steadily grew in Kolkata and Purulia despite a single use of sulfadoxine-pyrimethamine. Treatment failures with sulfadoxine-pyrimethamine were linked to quintuple or quadruple pfdhfr- pfdhps mutations (AICII-AGKAT, AICII-AGKAA, AICII-SGKGT, AICII-AGKAA, AICNI-AGKAA) in 2008-2009 (p < 0.001). The subsequent spread of mutant-haplotypes with higher in vitro sulfadoxine-pyrimethamine resistance (p < 0.001), such as the sextuple (dhfr-AIRNI+dhps-AGEAA, dhfr-ANRNL+dhps-AGEAA) and septuple (dhfr-AIRNI+dhps-AGEAT), mutations were observed in 2015-2017. Discussion: This successive spread of mutations with high in vitro sulfadoxine-pyrimethamine resistance confirmed the progressive increase in antifolate resistance even after an 8-year withdrawal of sulfadoxine-pyrimethamine.


Assuntos
Antimaláricos , Malária Falciparum , Humanos , Plasmodium falciparum/genética , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Sulfadoxina/farmacologia , Sulfadoxina/uso terapêutico , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Resistência a Medicamentos/genética , Mutação , Genômica , Resultado do Tratamento , Tetra-Hidrofolato Desidrogenase/genética , Combinação de Medicamentos
19.
Artigo em Inglês | MEDLINE | ID: mdl-33618651

RESUMO

BACKGROUND: There are anecdotal claims on the use of Cannabis sativa L. in the treatment of Alzheimer's disease, but there is a lack of scientific data to support the efficacy and safety of Cannabis sativa L. for Alzheimer's disease. AIM: The aim of the study was to evaluate the effect of aerial parts of Cannabis sativa L. on the cholinesterases and ß-secretase enzymes activities as one of the possible mechanisms of Alzheimer's disease. METHODS: The phytochemical and heavy metal contents were analysed. The extracts were screened for acetylcholinesterase, butyrylcholinesterase and ß-secretase activity. Cytotoxicity of extracts was performed in normal vero and pre-adipocytes cell lines. The extracts were characterized using high-performance thin layer chromatography and high-performance liquid chromatography for their chemical fingerprints. Alkaloids, flavonoids and glycosides were present amongst the tested phytochemicals. Cannabidiol concentrations were comparatively high in the hexane and dichloromethane than in dichloromethane: methanol (1:1) and methanol extracts. RESULTS: Hexane and dichloromethane extracts showed a better inhibitory potential towards cholinesterase activity, while water, hexane, dichloromethane: methanol (1:1) and methanol showed an inhibitory potential towards ß-secretase enzyme activity. All extracts showed no cytotoxic effect on pre-adipocytes and vero cells after 24- and 48-hours of exposure. CONCLUSION: Therefore, this may explain the mechanism through which AD symptoms may be treated and managed by Cannabis sativa L. extracts.


Assuntos
Doença de Alzheimer , Secretases da Proteína Precursora do Amiloide , Cannabis , Inibidores da Colinesterase , Extratos Vegetais , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Butirilcolinesterase/metabolismo , Cannabis/química , Chlorocebus aethiops , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Flores/química , Hexanos , Metanol , Cloreto de Metileno , Compostos Fitoquímicos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Células Vero
20.
Transfus Clin Biol ; 28(1): 123-127, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33285298

RESUMO

Since December 2019, the human populations of the 195 global countries continue experiencing grave health and life threats due to the current COVID-19 pandemic. As a result of the novelty of the pathogen, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), at present there is lack of preventive as well as therapeutic options for treating and managing the infection. The use of ancient immunotherapeutic technique - the convalescent plasma (CP) therapy, may act as an immediate and available option to control the COVID-19 pandemic. This review provides a concept and understanding on the CP therapy, its potential to control SARS-CoV-2 pandemic. The CP therapy might act as an immediate saviour for society from the virus. Although the CP therapy has exert affirmative result against COVID-19 it has not been recommended for long time use in COVID-19 and this review gives support for its possible application.


Assuntos
Anticorpos Antivirais/uso terapêutico , COVID-19/terapia , Pandemias , SARS-CoV-2 , Anticorpos Antivirais/sangue , COVID-19/sangue , Ensaios Clínicos como Assunto , Convalescença , Gerenciamento Clínico , Humanos , Imunização Passiva/efeitos adversos , Imunização Passiva/métodos , Plasmaferese , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Virulência , Soroterapia para COVID-19
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