Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Infect Disord Drug Targets ; 18(2): 96-104, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28820067

RESUMO

Ebola virus (EBOV) was discovered for the first time in 1976. It belongs to the family Filoviridae, which causes hemorrhagic fever that could lead to death in a few days. West Africa faced a major outbreak where symptoms appeared in the form of chills, myalgia, fever, diarrhea, and vomiting, and the disease finally reached a severe state as a result of hemorrhagic complications and failure of multiple organs. EBOV spreads by contact with body fluids of an infected person such as blood, saliva, urine, and seminal fluid, and also spreads by a contact with contaminated surfaces. Viral infection depends on the virus and host defenses. When the virus invades the body, the immune system becomes activated in an attempt to neutralize it. However, if this fails, EBOV viral infection spreads and leads to impaired innate and adaptive immune responses and uncontrollable viral replication. Consequently, the symptomatic patient is isolated and various medicinal regimens such as BCX-4430n TKM- EBOV are used, to cure EBOV, though, a specific treatment is not available. Accordingly, the aim of the present review is to survey and summarize the recent literature pertaining to the outbreak of EBOV, systematic infection of the human body, along with transmission and treatment. In addition, the review also aims to identify areas that need more research and development in combatting this dangerous virus. In the meantime, it should be noted that there is no fully FDA approved drug to treat infections by this virus. Therefore, there is a pressing need to focus on drug discovery along with public awareness to effectively manage any outbreaks in the future.


Assuntos
Surtos de Doenças/prevenção & controle , Ebolavirus/imunologia , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/transmissão , Doença pelo Vírus Ebola/virologia , Adenina/análogos & derivados , Adenosina/análogos & derivados , África Ocidental/epidemiologia , Animais , Antivirais/uso terapêutico , Descoberta de Drogas , Doença pelo Vírus Ebola/tratamento farmacológico , Humanos , Sistema Imunitário/imunologia , Nucleosídeos de Purina/uso terapêutico , Pirrolidinas , Replicação Viral/imunologia
2.
Avicenna J Med Biotechnol ; 9(1): 23-30, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28090277

RESUMO

BACKGROUND: Quorum Sensing (QS) is a mechanism used by bacteria to determine their physiological activities and coordinate gene expression based on cell to cell signaling. Many bacterial physiological functions are under the regulation of quorum sensing such as virulence, luminescence, motility, sporulation and biofilm formation. The aim of the present study was to isolate and characterize Quorum Sensing Inhibitory (QSI) substances from epiphytic bacteria residing on wild berries surfaces. METHODS: Fifty nine bacterial isolates out of 600 screened bacteria were successfully isolated. These bacteria were obtained from berry surfaces of different plants in the wild forests of Ajloun-Jordan. Screening for QSI activity using Chromobacterium violaceum ATCC 12472 monitor strain, resulted in isolating 6 isolates exhibiting QSI activity only, 11 isolates with QSI and antibacterial activity, and 42 isolates with antibacterial activity only. Three potential isolates S 130, S 153, and S 664, were gram positive rods and spore formers, catalase positive and oxidase negative. These were chosen for further testing and characterization. RESULTS: Different solvent extraction of the QSI substances based on polarity indicated that the activity of S 130 was in the butanol extract, S 153 activity in both chloroform and butanol; and for S 664, the activity was detected in the hexane extract. The chloroform extract of S 153 and hexane extract of S 664 were proteinaceous in nature while QSI substances of the butanol extract of S 130 and S 153 were non-proteinaceous. All the tested QSI substances showed a marked thermal stability when subjected at several time intervals to 70°C, with the highest stability observed for the butanol extract of S 153. Assessing the QSI substances using violacein quantification assay revealed varying degrees of activity depending upon the extracting solvent, type of the producer bacteria and the concentration of the substances. CONCLUSION: This study highlighted the potential of untapped reservoirs in nature to be used as a source of unique metabolite that may be further developed for therapy. The potential QSI substances included in this study are just one aspect to be further analyzed for use as biopharmaceutical agents.

3.
Dent J (Basel) ; 5(4)2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-29563432

RESUMO

Probiotics have a role in maintaining oral health through interaction with oral microbiome, thus contributing to healthy microbial equilibrium. The nature and composition of any individual microbiome impacts the general health, being a major contributor to oral health. The emergence of drug resistance and the side effects of available antimicrobials have restricted their use in an array of prophylactic options. Indeed, some new strategies to prevent oral diseases are based on manipulating oral microbiota, which is provided by probiotics. Currently, no sufficient substantial evidence exists to support the use of probiotics to prevent, treat or manage oral cavity diseases. At present, probiotic use did not cause adverse effects or increased risks of caries or periodontal diseases. This implicates no strong evidence against treatment using probiotics. In this review, we try to explore the use of probiotics in prevention, treatment and management of some oral cavity diseases and the possibilities of developing designer probiotics for the next generation of oral and throat complimentary healthcare.

4.
Arch Pharm (Weinheim) ; 347(11): 861-72, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25220428

RESUMO

A series of substituted 4-oxopyrido[2,3-a]phenothiazine-3-carboxylic acids (6a-d) were prepared via cyclization of the corresponding ethyl 7-(arylthioxy)-8-nitro(or azido)-4-oxoquinoline-3-carboxylates (3a-d/4a-d), followed by hydrolysis of the resultant esters (5a-d). Among these tetracyclics, compound 6a with unsubstituted terminal benzo-ring D was the most active against representative Gram-positive and Gram-negative bacterial strains. These compounds were also active against methicillin-resistant Staphylococcus aureus (MRSA), with very low toxicity to normal cells. Virtual screening using ligand-protein docking modeling predicted that the compounds 6a-d are potential inhibitors of the topoisomerase IV enzyme and that hydrophobic interactions and hydrogen bonds are the major molecular interactions between these compounds and the residues of the active site of topoisomerase IV.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Fenotiazinas/síntese química , Fenotiazinas/farmacologia , Animais , Antibacterianos/toxicidade , Domínio Catalítico , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , DNA Topoisomerase IV/antagonistas & inibidores , DNA Topoisomerase IV/química , Desenho de Fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Simulação de Acoplamento Molecular , Estrutura Molecular , Fenotiazinas/toxicidade , Conformação Proteica , Relação Estrutura-Atividade , Inibidores da Topoisomerase , Células Vero
5.
J Cancer Res Ther ; 8(3): 417-23, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23174725

RESUMO

BACKGROUND: The resistance of solid tumors to conventional therapies has prompted the need for alternative therapies. AIM: To evaluate in vitro and in vivo effect of extracts from Ononis hirta against resistant mouse mammary gland cell line (66 cl-4-GFP) and to use a combination of Ononis hirta extract with Bifidobacterium longum to target resistant solid tumors in mice. MATERIALS AND METHODS: Different solvent extracts of Ononis hirta were prepared and their in vitro antiproliferative activity was tested against 66 cl-4-GFP cell line using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC) were used to identify the active extracts. Balb/C mice were transplanted with 66 cl-4-GFP cell line and in vivo antitumor activity was assessed for the plant extract, Bifidobacterium longum, and a combination of plant extract and Bifidobacterium longum. Histological examination of tumors was performed using standard hematoxylin/eosin staining protocol while gram stain was used to detect the presence of anaerobic bacteria in these sections. RESULTS: A combination of Ononis hirta methanol extract and Bifidobacterium longum showed high ability in targeting solid mammary gland tumors in mice. It also induced extensive necrosis in these tumors. Thirty percent of mice treated with such combination were cured of their cancers. The mechanism underlying this anticancer activity involves immune system activation exemplified by the observed rejection of reinoculated tumors by cured mice. Chemical TLC analysis of the active methanol extract showed the presence of flavonoids, terpenoids, and alkaloids. HPLC analysis confirmed the presence of flavonoids and alkaloids in Ononis hirta methanol extract. CONCLUSION: The complete regression of the tumor is encouraging and shows that plant extracts in combination with Bifidobacterium longum is an inviting option to treat solid tumors.


Assuntos
Bifidobacterium/metabolismo , Fabaceae/metabolismo , Neoplasias Mamárias Animais/tratamento farmacológico , Neoplasias Mamárias Animais/imunologia , Extratos Vegetais/uso terapêutico , Animais , Bifidobacterium/imunologia , Linhagem Celular Tumoral , Feminino , Glândulas Mamárias Animais/imunologia , Glândulas Mamárias Animais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/farmacologia , Resultado do Tratamento , Carga Tumoral
6.
Molecules ; 17(3): 3291-303, 2012 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-22418930

RESUMO

The antiproliferative and antimicrobial effects of thirteen compounds isolated from Inula viscosa (L.) were tested in this study. The antiproliferative activity was tested against three cell lines using the MTT assay. The microdilution method was used to study the antimicrobial activity against two Gram positive bacteria, two Gram negative bacteria and one fungus. The apoptotic activity was determined using a TUNEL colorimetric assay. Scanning electron microscopy was used to study the morphological changes in treated cancer cells and bacteria. Antiproliferative activity was observed in four flavonoids (nepetin, 3,3'-di-O-methylquercetin, hispidulin, and 3-O-methylquercetin). 3,3'-di-O-Methylquercetin and 3-O-methylquercetin showed selective antiproliferative activity against MCF-7 cells, with IC(50) values of 10.11 and 11.23 µg/mL, respectively. Both compounds exert their antiproliferative effect by inducing apoptosis as indicted by the presence of DNA fragmentation, nuclear condensation, and formation of apoptotic bodies in treated cancer cells. The antimicrobial effect of Inula viscosa were also noticed in 3,3'-di-O-methylquercetin and 3-O-methyquercetin that inhibited Bacillus cereus at MIC of 62.5 and 125 µg/mL, respectively. Salmonella typhimurium was inhibited by both compounds at MIC of 125 µg/mL. 3,3'-di-O-Methylquercetin induced damage in bacterial cell walls and cytoplasmic membranes. Methylated quercetins isolated from Inula viscosa have improved anticancer and antimicrobial properties compared with other flavonoids and are promising as potential anticancer and antimicrobial agents.


Assuntos
Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Inula/química , Extratos Vegetais/isolamento & purificação , Animais , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/ultraestrutura , Candida albicans/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Chlorocebus aethiops , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Humanos , Concentração Inibidora 50 , Extratos Vegetais/farmacologia , Células Vero
7.
Sci Pharm ; 78(1): 33-45, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21179373

RESUMO

Forty four extracts from sixteen plants used traditionally as anticancer agents were evaluated in vitro for their antiproliferative activity against Hep-2, MCF-7, and Vero cell lines. Plants were fractionated using ethanol, methanol, chloroform, n-hexane, distilled water, and butanol. The antiproliferative activity was measured by MTT assay. TLC was used to identify active fractions. The apoptotic activity of active fractions was determined using TUNEL colorimetric assay. 20 of these extracts demonstrated significant antiproliferative activity against one or more of the cell lines. These extracts were prepared from Ononis hirta, Inula viscosa, Salvia pinardi, Verbascum sinaiticum and Ononis sicula. Methanol fractions of Ononis hirta (aerial parts) and Inula viscosa (flowers) were the most active fractions against MCF-7 cells with IC(50) of 27.96 and 15.78 Îg/ml respectively and they were less toxic against other cell lines. Other extracts showed lower activity against cancer cell lines. TLC analysis showed the presence of flavonoids and terpenoids in active plants while alkaloids were detected in Ononis hirta (aerial parts) extracts. Ononis hirta (aerial parts) and Inula viscosa (flowers) extracts exerted their antiproliferative activity by inducing apoptosis in cancer cell lines. Further studies are necessary for detailed chemical characterization and more extensive biological evaluation of the most active ingredients.

8.
Molecules ; 15(3): 1811-24, 2010 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-20336015

RESUMO

Antimicrobial activity and cytotoxicity of fifty one extracts of different parts of 14 plants were studied. Ethanol, methanol, aqueous, butanol, and n-hexane extracts were tested against three gram negative, two gram positive bacteria, and two fungi. Cytotoxicity and phytochemical screening were determined using MTT and TLC assays, respectively. Of the fifty one extracts, twenty two showed activities against different microorganisms with MICs ranging from 62.5 to 1000 microg/mL. The highest activity (100% inhibition) was for a butanol extract of Rosa damascena receptacles against Salmonella typhimurium and Bacillus cereus (MIC of 62.5 and 250 microg/mL) respectively. Butanol extract of Narcissus tazetta aerial parts and aqueous extract of Rosa damascena receptacles were both active against Candida albicans (MIC of 125 microg/mL). Methicillin-resistant Staphylococcus aureus was inhibited by butanol, aqueous extracts of Rosa damascena receptacles and butanol extract of Inula viscosa flowers (MIC of 500, 500, and 250 microg/mL) respectively. Rosa damascena receptacles and Verbascum sinaiticum flowers ethanol extract showed lowest cytotoxicity against Vero cell line (IC50 of 454.11 and 367.11). Most toxic was the ethanol extract of Ononis hirta aerial parts (IC50 72.50 microg/mL). Flavonoids and terpenoids were present in all plants. Ononis hirta and Narcissus tazetta contained alkaloids. The results validate the use of these plants and report for the first time bioactivity of Rosa damascena receptacles and further justifies the use of such screening programs in the quest for new drugs.


Assuntos
Anti-Infecciosos/farmacologia , Medicina Tradicional , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Animais , Bactérias/efeitos dos fármacos , Chlorocebus aethiops , Cromatografia em Camada Fina , Ensaios de Seleção de Medicamentos Antitumorais , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Células Vero
9.
Molecules ; 14(9): 3425-35, 2009 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-19783935

RESUMO

Antimicrobial and antiquorum sensing (AQS) activities of fourteen ethanolic extracts of different parts of eight plants were screened against four Gram-positive, five Gram-negative bacteria and four fungi. Depending on the plant part extract used and the test microorganism, variable activities were recorded at 3 mg per disc. Among the Grampositive bacteria tested, for example, activities of Laurus nobilis bark extract ranged between a 9.5 mm inhibition zone against Bacillus subtilis up to a 25 mm one against methicillin resistant Staphylococcus aureus. Staphylococcus aureus and Aspergillus fumigatus were the most susceptible among bacteria and fungi tested towards other plant parts. Of interest is the tangible antifungal activity of a Tecoma capensis flower extract, which is reported for the first time. However, minimum inhibitory concentrations (MIC's) for both bacteria and fungi were relatively high (0.5-3.0 mg). As for antiquorum sensing activity against Chromobacterium violaceum, superior activity (>17 mm QS inhibition) was associated with Sonchus oleraceus and Laurus nobilis extracts and weak to good activity (8-17 mm) was recorded for other plants. In conclusion, results indicate the potential of these plant extracts in treating microbial infections through cell growth inhibition or quorum sensing antagonism, which is reported for the first time, thus validating their medicinal use.


Assuntos
Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Extratos Vegetais/farmacologia , Percepção de Quorum/efeitos dos fármacos , Testes de Sensibilidade Microbiana
10.
Phytother Res ; 16(8): 751-3, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12458480

RESUMO

Aqueous, ethanol and butanol crude extracts of the aerial parts of ten plants exhibited variable degrees of antimicrobial activity against four bacterial and two fungal species. Aqueous extracts had low antimicrobial activity against E.coli, P.aeruginosa, B. cerreus, S.aureus, C.albicans and A.flavus. Avicennia marina (AM) aqueous extract exhibited a moderate antifungal activity. Ethanol and butanol crude extracts exhibited an improved antimicrobial activity. However, butanol exhibited a superior antimicrobial activity compared with aqueous and ethanol crudes. Compared with the standard antibiotics tested the butanol extract had the highest activity. Butanol extracts at 2000 microg/disc of AM, Lotus halophilus (LA), Pulicaria gnaphaloides (PG) and Capparis spinosa (CS) had a very good antibacterial activity against both gram-positive and -negative bacteria as well as moderate to good antifungal activity against C. albicans and A. flavus. Medicago laciniata (ML), Limonium axillare (LA) and (PG) butanol crude extract compared with standard chloramphenicol, tetracycline and nalidixic acid exhibited a superior antifungal activity.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/farmacologia , Plantas Medicinais , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Humanos , Medicina Tradicional , Testes de Sensibilidade Microbiana , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Catar
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...