Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 189
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Drug Chem Toxicol ; 45(2): 834-838, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32538189

RESUMO

There are an estimated 1 billion cases of superficial fungal infection globally. Fungal pathogens form biofilms within wounds and delay the wound healing process. Miconazole and terbinafine are commonly used to treat fungal infections. They induce the accumulation of reactive oxygen species (ROS) in fungi, resulting in the death of fungal cells. ROS are highly reactive molecules, such as oxygen (O2), superoxide anion (O2•-), hydrogen peroxide (H2O2) and hydroxyl radicals (•OH). Although ROS generation is useful for killing pathogenic fungi, it is cytotoxic to human keratinocytes. To the best of our knowledge, the effect of miconazole and terbinafine on HaCaT cells has not been studied with respect to intracellular ROS stimulation. We hypothesized that miconazole and terbinafine have anti-wound healing effects on skin cells when used in antifungal treatment because they generate ROS in fungal cells. We used sulforhodamine B protein staining to investigate cytotoxicity and 2',7'-dichlorofluorescein diacetate to determine ROS accumulation at the 50% inhibitory concentrations of miconazole and terbinafine in HaCaT cells. Our preliminary results showed that topical treatment with miconazole and terbinafine induced cytotoxic responses, with miconazole showing higher cytotoxicity than terbinafine. Both the treatments stimulated ROS in keratinocytes, which may induce oxidative stress and cell death. This suggests a negative correlation between intracellular ROS accumulation in keratinocytes treated with miconazole or terbinafine and the healing of fungi-infected skin wounds.


Assuntos
Peróxido de Hidrogênio , Miconazol , Humanos , Peróxido de Hidrogênio/farmacologia , Queratinócitos , Miconazol/metabolismo , Miconazol/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Terbinafina/metabolismo , Terbinafina/toxicidade
2.
Crit Rev Microbiol ; 44(1): 40-78, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28423970

RESUMO

Antimicrobial resistance of disease-related microorganisms is considered a worldwide prevalent and serious issue which increases the failure of treatment outcomes and leads to high mortality. Considering that the increased resistance to systemic antimicrobial therapy often needs of the use of more toxic agents, topical antimicrobial therapy emerges as an attractive route for the treatment of infectious diseases. The topical antimicrobial therapy is based on the absorption of high drug doses in a readily accessible skin surface, resulting in a reduction of microbial proliferation at infected skin sites. Topical antimicrobials retain the following features: (a) they are able to escape the enzymatic degradation and rapid clearance in the gastrointestinal tract or the first-pass metabolism during oral administration; (b) alleviate the physical discomfort related to intravenous injection; (c) reduce possible adverse effects and drug interactions of systemic administrations; (d) increase patient compliance and convenience; and (e) reduce the treatment costs. Novel antimicrobials for topical application have been widely exploited to control the emergence of drug-resistant microorganisms. This review provides a description of antimicrobial resistance, common microorganisms causing skin and soft tissue infections, topical delivery route of antimicrobials, safety concerns of topical antimicrobials, recent advances, challenges and future prospective in topical antimicrobial development.


Assuntos
Antibacterianos/administração & dosagem , Dermatopatias Bacterianas/tratamento farmacológico , Infecções dos Tecidos Moles/tratamento farmacológico , Administração Tópica , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/metabolismo , Farmacorresistência Bacteriana , Humanos , Dermatopatias Bacterianas/microbiologia , Infecções dos Tecidos Moles/microbiologia
3.
J Microencapsul ; 31(8): 754-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24963963

RESUMO

l-ascorbic acid is an abundant water-soluble nutrient found in vegetables and fruits. It enhances the cell proliferation, which is helpful in wound healing process. However, it is relatively unstable and easily degraded under external environments including acidity, alkalinity, evaporation, heat, oxidization, light or moisture. Its storage remains challenged. This study reported the development of l-ascorbic acid microcapsules using the natural protein, gelatin, and the natural polysaccharide, agar, as the wall protection carrier. The physical properties including entrapment efficiency, particle size, surface morphology, chemical compositions and release profile were identified. The cell proliferation of l-ascorbic acid microcapsules was stronger than the free drug. Significant cell growth in microencapsulated l-ascorbic acid-treated human epithelial HaCaT cells was observed when compared with untreated control. Since cell proliferation and wound repair are closely related, it is believed that l-ascorbic acid microcapsules would effectively increase the potential effect of wound healing activity in human skin.


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/metabolismo , Cicatrização/efeitos dos fármacos , Ácido Ascórbico/química , Cápsulas , Linhagem Celular , Células Epiteliais/citologia , Humanos
4.
J Microencapsul ; 30(2): 143-50, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22793936

RESUMO

The therapeutic efficiency and topical performance of drug-containing microcapsules varied when the drugs existed in an internal oil phase or an internal aqueous phase within the wall shell or wall matrix of microcapsules. In this study, chitosan-based (oil-in-water) and agar-gelatin-based (water-in-oil) microencapsulation systems containing berberine were applied to cotton fabrics to provide an anti-Staphylococcus aureus activity for textile materials. The berberine microcapsule-treated cotton samples were subjected to various washing cycles and their surface morphology, chemical compositions and antibacterial property were investigated after washing. The SEM images and Fourier transform infrared analysis showed that the amount of microcapsules on cotton samples decreased gradually with an increase in washing cycles. After 20 washing cycles, the cotton fabrics with agar-gelatin (water-in-oil) microcapsules containing berberine still exhibited the anti-S. aureus activity. However, the chitosan-based (oil-in-water) system did not show any growth inhibition towards S. aureus but only in the contact areas.


Assuntos
Antibacterianos/química , Berberina/química , Fibra de Algodão , Staphylococcus aureus/crescimento & desenvolvimento , Têxteis , Cápsulas
5.
Int J Biol Macromol ; 237: 123982, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36907297

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) has emerged since the early 1960s. The increasing resistance of pathogens to currently used antibiotics requires the urgent discovery of new antimicrobials effective in combating drug-resistant bacteria. From past to present, medicinal plants are useful to cure human diseases. Corilagin (ß-1-O-galloyl-3,6-(R)-hexahydroxydiphenoyl-d-glucose), commonly found in Phyllanthus species, exerts potentiating effect on ß-lactams against MRSA. However, its biological effect may not be fully utilized. Therefore, incorporating microencapsulation technology with the delivery of corilagin would be more effective in utilizing the potential effect on biomedical applications. This work reports the development of a safe micro-particulate system which combined agar with gelatin as wall matrix materials for topical delivery of corilagin in order to eliminate the potential toxicity of the crosslinker formaldehyde. The optimal parameters for microsphere preparation were identified and the particle size of optimal microspheres was 20.11 µm ± 3.58. Antibacterial studies revealed that micro-trapped corilagin (minimum bactericidal concentration, MBC = 0.5 mg/mL) possessed a higher potency against MRSA than free corilagin (MBC = 1 mg/mL). The in vitro skin cytotoxicity showed the safety of the corilagin-loaded microspheres for topical applications, with approximately 90 % of HaCaT cell viability. Our results demonstrated the potential of corilagin-loaded gelatin/agar microspheres for the applicable bio-textile products to treat drug-resistant bacterial infections.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Humanos , Staphylococcus aureus , Gelatina/farmacologia , Ágar/farmacologia , Microesferas , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia
6.
Rhinology ; 49(2): 148-54, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21743868

RESUMO

BACKGROUND: The research addressed to detect new molecular targets in the development of therapeutic strategies aimed to repair bone tissues. The AIM OF THIS STUDY was to determine the potential osteogenic activity of bone cells from the nasal septum and their use to perform accurate molecular analysis from a single sample. METHODOLOGY: The cells, after nasal septum surgery, were subjected to gene silencing, Reverse Transcriptase - Polymerase Chain reactions, immunocytochemistry and chromatin immunoprecipitation. RESULTS: Cells from the nasal septum can give rise to mature osteoblasts that express osteogenic markers (ALP, Runx2, Slug) and are able to mineralize. We demonstrated that Runx2, a transcription factor critical in early osteospecific differentiation, interacts in vivo with the promoter of the SLUG gene, a marker of osteoblast maturation. CONCLUSIONS: We demonstrated that nasal septum-derived osteoblasts represent an interesting alternative source for bone forming cells, and a promising material to be utilized in bone cellular therapy.


Assuntos
Septo Nasal/citologia , Osteogênese/fisiologia , Engenharia Tecidual/métodos , Adulto , Idoso , Imunoprecipitação da Cromatina , Subunidade alfa 1 de Fator de Ligação ao Core , Feminino , Citometria de Fluxo , Inativação Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Osteoblastos/fisiologia , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição da Família Snail , Fatores de Transcrição , Transfecção
7.
Chem Biol Interact ; 320: 109023, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32097615

RESUMO

Antimicrobial resistance remains a serious problem that results in high mortality and increased healthcare costs globally. One of the major issues is that resistant pathogens decrease the efficacy of conventional antimicrobials. Accordingly, development of novel antimicrobial agents and therapeutic strategies is urgently needed to overcome the challenge of antimicrobial resistance. A potential strategy is to kill pathogenic microorganisms via the formation of reactive oxygen species (ROS). ROS are defined as a number of highly reactive molecules that comprise molecular oxygen (O2), superoxide anion (O2•-), hydrogen peroxide (H2O2) and hydroxyl radicals (•OH). ROS exhibit antimicrobial actions against a broad range of pathogens through the induction of oxidative stress, which is an imbalance between ROS and the ability of the antioxidant defence system to detoxify ROS. ROS-dependent oxidative stress can damage cellular macromolecules, including DNA, lipids and proteins. This article reviews the antimicrobial action of ROS, challenges to ROS hypothesis, work to solidify ROS-mediated antimicrobial lethality hypothesis, recent developments in antimicrobial agents using ROS as an antimicrobial strategy, safety concerns related to ROS, and future directions in ROS research.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , DNA Bacteriano/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Animais , Humanos , Estresse Oxidativo
8.
Eur J Med Chem ; 124: 537-543, 2016 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-27598239

RESUMO

Two complexes dichloro(9,9-dihexyl-4,5-diazafluorene)platinum(II) (Pt-DHF) and dichloro(9,9-dihexyl-4,5-diazafluorene)palladium(II) (Pd-DHF) were synthesized and their in vivo antitumour activity was investigated using an athymic nude mice model xenografted with human Hep3B carcinoma cells. Pt-DHF- and Pd-DHF-treated groups showed significant tumour growth inhibition (with about 9-fold and 3-fold tumour growth retardation) when compared with the vehicle control group. The liver toxicology effects on the animals of the two compounds were investigated. Pt-DHF and Pd-DHF-treated groups had a lower alanine transaminase and aspartate transaminase values than those of the vehicle treated group as the animals from the vehicle control group had very heavy hepatoma burden. We assume that both complexes could be further investigated as effective antitumour agents and it is worthwhile to study their underlying working mechanism.


Assuntos
Complexos de Coordenação/síntese química , Compostos Organoplatínicos/síntese química , Compostos Organoplatínicos/farmacologia , Paládio/química , Platina/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Modelos Animais de Doenças , Ativação Enzimática/efeitos dos fármacos , Xenoenxertos , Humanos , Fígado/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Compostos Organoplatínicos/química , Compostos Organoplatínicos/uso terapêutico , Paládio/farmacologia , Paládio/uso terapêutico , Platina/farmacologia , Platina/uso terapêutico
9.
Biomed Pharmacother ; 80: 145-150, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27133051

RESUMO

Tumour growth is closely related to the development of new blood vessels to supply oxygen and nutrients to cancer cells. Without the neovascular formation, tumour volumes cannot increase and undergo metastasis. Antiangiogenesis is one of the most promising approaches for antitumour therapy. The exploration of new antiangiogenic agents would be helpful in antitumour therapy. Quinoline is an aromatic nitrogen compound characterized by a double-ring structure which exhibits a benzene ring fused to pyridine at two adjacent carbon atoms. The high stability of quinoline makes it preferable in a variety of therapeutic and pharmaceutical applications, including antitumour treatment. This work is to examine the potential antiangiogenic activity of the synthetic compound 2-Formyl-8-hydroxy-quinolinium chloride. We found that 2-Formyl-8-hydroxy-quinolinium chloride could inhibit the growth of human umbilical vein endothelial cells in vitro. Using the diethylnitrosamine-induced hepatocarcinogenesis model, 2-Formyl-8-hydroxy-quinolinium chloride showed strong antiangiogenic activity. Furthermore, 2-Formyl-8-hydroxy-quinolinium chloride could inhibit the growth of large Hep3B xenografted tumour from the nude mice. We assume that 2-Formyl-8-hydroxy-quinolinium chloride could be a potential antiangiogenic and antitumour agent and it is worthwhile to further study its underlying working mechanism.


Assuntos
Inibidores da Angiogênese/farmacologia , Hidroxiquinolinas/farmacologia , Compostos de Quinolínio/farmacologia , Inibidores da Angiogênese/química , Inibidores da Angiogênese/uso terapêutico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinogênese/patologia , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dietilnitrosamina , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Hidroxiquinolinas/química , Hidroxiquinolinas/uso terapêutico , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Camundongos Endogâmicos C57BL , Camundongos Nus , Compostos de Quinolínio/química , Compostos de Quinolínio/uso terapêutico , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Biochim Biophys Acta ; 1013(1): 36-41, 1989 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-2790036

RESUMO

It is known that iron chelators (such as desferrioxamine) are potent inhibitors of both cell proliferation and erythroid differentiation. We have shown with in vitro studies that in the case of tumor cells desferrioxamine is even more efficient in inhibiting cell proliferation when entrapped in liposomes consisting of egg yolk phosphatidylcholine. At the same time liposome-entrapped desferrioxamine retains only a slight effect on hexamethylenebisacetamide induction of erythroid differentiation and hemoglobin accumulation of murine erythroleukemic Friend cells. Based on these findings, we propose liposome-entrapped desferrioxamine as potential antineoplastic agent as well as a specific chemical for the study of both iron metabolism and distribution in normal and neoplastic cells. In addition, unlike free desferrioxamine, the liposome-entrapped drug could also be used in combination with inducers of differentiation. With respect to this issue, it is possible that liposome-entrapped desferrioxamine, might permit erythroid differentiation of both neoplastic cells as well as normal stem cells.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Desferroxamina/farmacologia , Lipossomos , Fosfatidilcolinas , Animais , Linhagem Celular , Técnica de Fratura por Congelamento , Vírus da Leucemia Murina de Friend , Cinética , Leucemia Eritroblástica Aguda/patologia , Camundongos , Microscopia Eletrônica
11.
Biochim Biophys Acta ; 886(2): 203-13, 1986 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-3008852

RESUMO

The receptor for transferrin plays an important role both in tumor cell growth and in hemoglobin synthesis. In this paper, we demonstrate that the monoclonal antibody 42/6 to human transferrin receptor inhibits iron uptake in the human leukemic K562 cell line and suppresses hemoglobin accumulation in K562 cells induced to erythroid differentiation by butyric acid. In contrast, only slight inhibitory effects were observed on cell proliferation of both uninduced and erythroid-induced K562 cells treated with the 42/6 monoclonal antibody. In addition, the 42/6 monoclonal antibody to human transferrin receptor does not inhibit butyric acid-induced accumulation of gamma-globin mRNA. The effect of the 42/6 monoclonal antibody on hemoglobin synthesis appears to be restricted to human cell lines, as murine Friend erythroleukemic cells undergo erythroid differentiation when cultured in the presence of hexamethylenebisacetamide plus the 42/6 monoclonal antibody. The findings reported in this paper suggest (a) a dissociation of iron transport and accumulation of heme molecules from the expression of globin genes and (b) a different requirement of iron uptake by different iron-dependent functions such as cell proliferation and hemoglobin expression.


Assuntos
Anticorpos Monoclonais/imunologia , Hemoglobinas/biossíntese , Leucemia Mieloide/metabolismo , Receptores de Superfície Celular/fisiologia , Butiratos/farmacologia , Ácido Butírico , Diferenciação Celular/efeitos dos fármacos , Divisão Celular , Linhagem Celular , Eritropoese , Globinas/genética , Humanos , Ferro/metabolismo , Leucemia Mieloide/patologia , RNA Mensageiro/análise , Receptores de Superfície Celular/imunologia , Receptores da Transferrina
12.
J Mol Biol ; 203(2): 385-90, 1988 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-3199439

RESUMO

In order to identify putative control signals of gene expression, 634 mammalian DNA sequences spanning 1.8 x 10(6) base-pairs were analysed and the frequencies of 1024 oligonucleotides five bases long (5-tuples) were determined. We defined as rare those 5-tuples having an observed frequency less than 50% of that expected by chance on the basis of base composition, and which had a reduction in frequency not attributable to CpG suppression or to coding constraints. Very few rare 5-tuples were identified; in addition, three oligonucleotides, reverse complements of rare 5-tuples, were found to have a frequency ranging between 0.582 and 0.671. The frequency of most of the rare 5-tuples was higher in 5' promoter regions as compared to exonic segments, so imitating the distribution pattern of known signals. Some of the rare 5-tuples identified by this strategy belonged to a portion of the nine base-pair binding site in promoters, which is also known as the octamer motif. In addition, three of the rare oligonucleotides were found to be located within other regulatory elements, previously identified by techniques of molecular biology. Two rare 5-tuples were found within sites of interaction between DNA and proteins, one of them being a transcriptional factor. The available data about known control sequences involved in gene expression in mammals therefore provide evidence for a role in gene regulation of the rare oligonucleotide selected.


Assuntos
DNA , Mamíferos/genética , Oligonucleotídeos/análise , Sequências Reguladoras de Ácido Nucleico , Animais , Sequência de Bases , DNA/genética , Regulação da Expressão Gênica , Dados de Sequência Molecular , Regiões Promotoras Genéticas
13.
Med Chem ; 1(4): 327-33, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16789890

RESUMO

Several medicinal plants can be employed to produce extracts exhibiting biological effects. The aim of this work was to verify the ability of extracts derived from different medicinal plants of Bangladesh in interfering with specific DNA-protein interactions. The rationale for this study is based on the observation that alteration of gene transcription represents a very promising approach to control the expression of selected genes and could be obtained using different molecules acting on the interactions between DNA and transcription factors (TFs). We have analysed the antiproliferative activity of extracts from the medicinal plants Hemidesmus indicus, Polyalthia longifolia, Aphanamixis polystachya, Moringa oleifera, Lagerstroemia speciosa, Paederia foetida, Cassia sophera, Hygrophila auriculata and Ocimum sanctum. Antiproliferative activity was assayed on different human cell lines, including erythroleukemia K562, B-lymphoid Raji, T-lymphoid Jurkat and erythroleukemia HEL cell lines. We employed the electrophoretic mobility shift assay (EMSA) as a suitable technique for the identification of plant extracts altering the binding between transcription factors and the specific DNA elements. We found that low concentrations of Hemidesmus indicus, Polyalthia longifolia, Moringa oleifera and Lagerstroemia speciosa, and very low concentrations of Aphanamixis polystachya extracts inhibit the interactions between nuclear factors and target DNA elements mimicking sequences recognized by the nuclear factor kappaB (NF-kappaB). On the contrary, high amount of extracts from Paederia foetida, Cassia sophera, Hygrophila auriculata or Ocimum sanctum were unable to inhibit NF-kappaB/DNA interactions. Extracts inhibiting both NF-kappaB binding activity and tumor cell growth might be a source for anti-tumor compounds, while extracts inhibiting NF-kappaB/DNA interactions with lower effects on cell growth, could be of interest in the search of compounds active in inflammatory diseases, for which inhibition of NF-kappaB binding activity without toxic effects should be obtained.


Assuntos
DNA/metabolismo , NF-kappa B/metabolismo , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Fatores de Transcrição/metabolismo , Antineoplásicos/farmacologia , Bangladesh , Sítios de Ligação/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , DNA/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Mimetismo Molecular , NF-kappa B/antagonistas & inibidores , NF-kappa B/efeitos dos fármacos
14.
Exp Hematol ; 15(11): 1145-52, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2445597

RESUMO

We have studied the effects of hemin on the inhibition of K562 cell erythroid differentiation mediated by a monoclonal antibody to the human transferrin receptor. In the absence of hemin, the monoclonal antibody 42/6 suppresses the increase of hemoglobin accumulation induced by butyric acid or 5-azacytidine (5-azaCR). In contrast, in the presence of hemin, the hemin-resistant K562(h) cell line is induced to hemoglobin production by treatment with 5-azaCR even in the presence of the monoclonal antibody to human transferrin receptor. The results obtained suggest (1) that the human leukemic K562 cells treated with monoclonal antibodies to human transferrin receptor might retain molecular properties similar to those found in erythroid cells from subjects affected by alterations of iron metabolism, and (2) that hemin might allow hemoglobin synthesis in erythroid cells whose iron uptake is inhibited by monoclonal antibodies to human transferrin receptors.


Assuntos
Anticorpos Monoclonais , Heme/farmacologia , Hemoglobinas/metabolismo , Receptores da Transferrina/fisiologia , Animais , Azacitidina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Humanos , Cinética , Leucemia Eritroblástica Aguda/fisiopatologia , Leucemia Experimental/fisiopatologia , Camundongos , Receptores da Transferrina/efeitos dos fármacos , Receptores da Transferrina/imunologia
15.
Exp Hematol ; 17(8): 859-64, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2475359

RESUMO

The isolation of a K562 cell line, K562(S)R, resistant to 1-beta-D-arabinofuranosylcytosine (ara-C)-mediated erythroid induction, is described. Ara-C (10-50 microM) inhibits cell growth of K562(S)R cells but is not able to activate the program of erythroid induction. This failure is associated with the lack in the increase of accumulation of epsilon-globin and gamma-globin mRNA sequences in ara-C-treated K562(S)R cells. This cell line could be of interest for studies focused on molecular mechanisms of activation of globin genes in K562 cells.


Assuntos
Separação Celular/métodos , Citarabina/farmacologia , Eritrócitos/citologia , Azacitidina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Resistência a Medicamentos , Globinas/genética , Hemoglobinas/genética , RNA Mensageiro/metabolismo , Células Tumorais Cultivadas/metabolismo
16.
Eur J Pharm Sci ; 78: 225-33, 2015 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-26209880

RESUMO

Cystic Fibrosis (CF) is the most diffuse autosomal recessive genetic disease affecting Caucasians. A persistent recruitment of neutrophils in the bronchi of CF patients contributes to exacerbate the airway tissue damage, suggesting that modulation of chemokine expression may be an important target for the patient's well being thus the identification of innovative anti-inflammatory drugs is considered a longterm goal to prevent progressive tissue deterioration. Phloridzin, isolated from Malus domestica by a selective molecular imprinting extraction, and its structural analogues, Phloridzin heptapropionate (F1) and Phloridzin tetrapropionate (F2), were initially investigated because of their ability to reduce IL-6 and IL-8 expression in human CF bronchial epithelial cells (IB3-1) stimulated with TNF-α. Release of these cytokines by CF cells was shown to be controlled by the Transcription Factor (TF) NF-kB. The results of the present investigation show that of all the derivatives tested, Phloridzin tetrapropionate (F2) is the most interesting and has greatest potential as it demonstrates inhibitory effects on the expression and production of different cytokines involved in CF inflammation processes, including RANTES, VEGF, GM-CSF, IL-12, G-CSF, MIP-1b, IL-17, IL-10 and IP-10, without any correlated anti-proliferative and pro-apoptotic effects.


Assuntos
Citocinas/antagonistas & inibidores , Florizina/análogos & derivados , Florizina/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fibrose Cística/metabolismo , Citocinas/genética , Citocinas/metabolismo , DNA/metabolismo , Frutas , Humanos , Malus , NF-kappa B/metabolismo , Florizina/isolamento & purificação , Extratos Vegetais/química , RNA Mensageiro/metabolismo
17.
Int J Mol Med ; 35(2): 503-10, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25482299

RESUMO

Aspergillus niger (A. niger) is a common species of Aspergillus molds. Cutaneous aspergillosis usually occurs in skin sites near intravenous injection and approximately 6% of cutaneous aspergillosis cases which do not involve burn or HIV-infected patients are caused by A. niger. Biomaterials and biopharmaceuticals produced from microparticle-based drug delivery systems have received much attention as microencapsulated drugs offer an improvement in therapeutic efficacy due to better human absorption. The frequently used crosslinker, glutaraldehyde, in gelatin-based microencapsulation systems is considered harmful to human beings. In order to tackle the potential risks, agarose has become an alternative polymer to be used with gelatin as wall matrix materials of microcapsules. In the present study, we report the eco-friendly use of an agarose/gelatin-based microencapsulation system to enhance the antifungal activity of gallic acid and reduce its potential cytotoxic effects towards human skin keratinocytes. We used optimal parameter combinations, such as an agarose/gelatin ratio of 1:1, a polymer/oil ratio of 1:60, a surfactant volume of 1% w/w and a stirring speed of 900 rpm. The minimum inhibitory concentration of microencapsulated gallic acid (62.5 µg/ml) was significantly improved when compared with that of the original drug (>750 µg/ml). The anti-A. niger activity of gallic acid -containing microcapsules was much stronger than that of the original drug. Following 48 h of treatment, skin cell survival was approximately 90% with agarose/gelatin microcapsules containing gallic acid, whereas cell viability was only 25-35% with free gallic acid. Our results demonstrate that agarose/gelatin-based microcapsules containing gallic acid may prove to be helpful in the treatment of A. niger-induced skin infections near intravenous injection sites.


Assuntos
Antifúngicos/farmacologia , Aspergilose/tratamento farmacológico , Aspergillus niger/crescimento & desenvolvimento , Dermatomicoses/tratamento farmacológico , Ácido Gálico/farmacologia , Gelatina/farmacologia , Sefarose/farmacologia , Antifúngicos/química , Cápsulas , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Ácido Gálico/química , Gelatina/química , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Sefarose/química
18.
Hum Mutat ; 18(1): 70-81, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11438995

RESUMO

In the present paper, biospecific interaction analysis (BIA) was performed using surface plasmon resonance (SPR) and biosensor technologies to detect the Trp1282Ter mutation (W1282X) of the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) gene. We first immobilized on a SA5 sensor chip a single-stranded biotinylated oligonucleotide containing the sequence involved in this mutation, and the efficiency of hybridization of oligonucleotide probes differing in length was determined. Second, we immobilized on different SA5 sensor chips biotinylated polymerase-chain reaction (PCR) products from a normal subject as well as from heterozygous and homozygous W1282X samples. The results obtained show that both allele-specific 10- and 12-mer oligonucleotides are suitable probes to detect W1282X mutations of the cystic fibrosis gene under standard BIA experimental conditions. During the association phase performed at 25 degrees C, discrimination between mismatched and full matched hybrids was readily and reproducibly observed by using the 10-mer W1282X probes. By contrast, when the 12-mer DNA probes were employed, discrimination between mismatched and full matched hybrids was observed during the dissociation phase. Taken together, the results presented suggest that BIA is an easy, speedy, and automatable approach to detect point mutations leading to cystic fibrosis. By this procedure, it is possible to perform real-time monitoring of hybridization between target single stranded PCR products obtained by using as substrates DNA isolated from normal or heterozygous subjects, and homozygous W1282X CF samples and oligonucleotide probes, therefore enabling a one-step, non-radioactive protocol to perform diagnosis.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/genética , Testes Genéticos/métodos , Mutação de Sentido Incorreto/genética , Mutação Puntual/genética , Ressonância de Plasmônio de Superfície/métodos , Automação , Sequência de Bases , Biotinilação , Fibrose Cística/diagnóstico , Análise Mutacional de DNA/métodos , DNA de Cadeia Simples/química , DNA de Cadeia Simples/genética , Genótipo , Humanos , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Hibridização de Ácido Nucleico , Sondas de Oligonucleotídeos/química , Sondas de Oligonucleotídeos/genética , Reação em Cadeia da Polimerase/métodos , Fatores de Tempo
19.
Gene ; 16(1-3): 141-8, 1981 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6177582

RESUMO

We have determined the nucleotide sequence of two cloned cDNAs corresponding to the mRNA of mouse embryonic y2 globin. The combined overlapping sequences span a total of 480 bp, beginning at the codon corresponding to amino acido residue 21 and extending to the AATAAA sequence in the 3' untranslated region. Therefore, when the amino acid sequence encoded by the cDNA is combined with the available amino acid sequence, a complete y2 protein sequence can be obtained. Comparisons, at the nucleotide level, between the known beta- and beta-like globin sequences and the y2 sequence show that the embryonic, fetal-adult duplication occurred approx. 160 million years (MY) ago and that the embryonic-fetal duplication occurred approx. 100 MY ago.


Assuntos
Hemoglobina Fetal/genética , Camundongos/genética , RNA Mensageiro/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Recombinante/metabolismo , Escherichia coli/genética , Hibridização de Ácido Nucleico , Filogenia , Plasmídeos
20.
Gene ; 31(1-3): 241-5, 1984 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6084630

RESUMO

Cytoplasmic poly(A)+mRNA from 12-day mouse-yolk-sac erythroid cells has been used to prepare a cDNA library in the plasmid pBR322. One clone containing sequences coding for the alpha-like embryonic globin chain x, pHE52, has been identified by hybrid selection and in vitro translation of the complementary mRNA. The nucleotide sequence of pHE52 confirms that it codes for an embryonic alpha-like globin chain. The insert sequence is 316 nucleotides long, contains the codons corresponding to amino acid residues 43-141, and extends into the 3' untranslated region. An analysis of the nucleotide sequence of pHE52 and the other known alpha globins suggests that the adult-embryonic divergence began approx. 400 million years ago reflecting a difference in the evolutionary history of the alpha- and beta-globin gene complexes.


Assuntos
Globinas/genética , Camundongos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Galinhas/genética , DNA Recombinante , Hemoglobina Fetal/genética , Globinas/biossíntese , Humanos , Filogenia , Biossíntese de Proteínas , RNA Mensageiro/genética , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA