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1.
Phys Chem Chem Phys ; 25(27): 17943-17951, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37376968

RESUMO

Due to the pronounced effect of the confined environment on the photochemical properties of 4-hydroxybenzylidene imidazolinone (HBI), a GFP-related chromophore, imidazolidinone and imidazothiazolone analogues have been studied as fluorescent probes. Their photoisomerization and their thermal reversion were studied under 365-nm-irradiation, resulting in observation of an enthalpy-entropy compensation effect. Theoretical studies were carried out to shed light on the thermal reversion mechanism. Moreover, photophysical studies of benzylidene imidazothiazolone in the presence of dsDNA revealed fluorescence enhancement. The prepared compounds could be considered as a valuable tool for the detailed investigation of physicochemical, biochemical, or biological systems.


Assuntos
Corantes Fluorescentes , Proteínas de Fluorescência Verde/química , Fluorescência , Termodinâmica , Entropia
2.
Res Vet Sci ; 115: 211-220, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28505549

RESUMO

The immunoprotective effect of Panax ginseng (Pg) extract was investigated in a mouse mastitis model. Lactating female mice were intramammarily inoculated with Pg or placebo, and then were challenged with S. aureus, while other group was inoculated with S. aureus alone. The number of bacteria recovered from mammary glands was significantly lower in Pg-treated S. aureus-infected mice (group I) compared with placebo-treated S. aureus-infected mice (group II) and S. aureus-infected mice (group III). The mRNA expression of TLR2, TLR4, IL-1α and TNF-α was influenced by treatment; being the transcript levels for all genes higher in group I compared with group II and III. Activation of NF-κB and the number of monocytes-macrophages in mammary gland tissue was significantly increased in group I compared with group II and III. Pg extract was able to trigger an adequate immune response to confront an infection demonstrating its protective effect and potential for preventing bovine intramammary infections.


Assuntos
Glândulas Mamárias Animais/imunologia , Mastite Bovina/imunologia , Panax/química , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/fisiologia , Animais , Bovinos , Modelos Animais de Doenças , Feminino , Lactação , Mastite Bovina/microbiologia , Camundongos Endogâmicos BALB C , Monocinas/metabolismo , Extratos Vegetais/administração & dosagem , Substâncias Protetoras/administração & dosagem , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Receptores Toll-Like/metabolismo
3.
Vet Immunol Immunopathol ; 144(1-2): 52-60, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21840064

RESUMO

The lack of efficacy of conventional strategies for the maintenance of healthy udders in domestic cattle has prompted studies on the use of immunomodulators or biological response modifiers (BRM) for this purpose. These compounds are agents that modify the host's response to pathogens leading to beneficial effects on disease outcome. The objective of this study was to evaluate the effects of a single intramammary infusion of Panax ginseng (GS) extract on the amount of pro-inflammatory cytokines and the number of monocytes/macrophages present in bovine mammary tissues at drying off. Eight mammary quarters from six nonpregnant cows in late lactation were infused with 10 mL of GS (3mg/mL), six quarters were treated with 10 mL of placebo (vehicle alone) and six quarters were maintained as uninoculated controls. The analyses of tumor necrosis factor-alpha (TNF-α) by immunohistochemistry revealed that the production of this proinflammatory cytokine significantly increased (P<0.05) in the inoculated mammary glands of cows following BRM inoculation, whereas the interleukin-1 alpha (IL-1α) and IL-6 staining area was not affected by BRM treatment. The number of monocytes/macrophages detected with CD14 antibody was significantly higher (P<0.05) in BRM-treated quarters than in placebo and uninoculated control quarters. These results indicated an immunomodulator potential of the BRM used. The beneficial effect of the extract could be used as alternative therapy in the control of mastitis at drying off, either alone or in conjunction with dry cow antibiotic therapy.


Assuntos
Citocinas/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Glândulas Mamárias Animais/efeitos dos fármacos , Mastite Bovina/prevenção & controle , Panax , Fitoterapia/veterinária , Extratos Vegetais/uso terapêutico , Animais , Western Blotting/veterinária , Bovinos , Feminino , Interleucina-1alfa/metabolismo , Interleucina-6/metabolismo , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Mastite Bovina/tratamento farmacológico , Mastite Bovina/patologia , Fator de Necrose Tumoral alfa/metabolismo
4.
Braz. j. microbiol ; 39(2): 245-250, Apr.-June 2008. tab
Artigo em Inglês | LILACS | ID: lil-487699

RESUMO

This study was performed to determine the susceptibility patterns and the colonization rate of Group B Streptococcus (GBS) in a population of pregnant women. From January 2004 to December 2006, vaginal-rectal swabs were obtained from 1105 women attending Dr. Ramón Madariaga Hospital, in Posadas, Misiones, Argentina. The carriage rate of GBS among pregnant women was 7.6 percent. A total of 62 GBS strains were randomly selected for in vitro susceptibility testing to penicillin G, ampicillin, tetracycline, levofloxacin, gatifloxacin, ciprofloxacin, quinupristin-dalfopristin, linezolid, vancomycin, rifampicin, trimethoprim-sulfametoxazol, nitrofurantoin, gentamicin, clindamycin and erythromycin, and determination of resistance phenotypes. No resistance to penicillin, ampicillin, quinupristin-dalfopristin, linezolid, and vancomycin was found. Of the isolates examined 96.8 percent, 98.3 percent, 46.8 percent, and 29.0 percent were susceptible to rifampicin, nitrofurantoin, trimethoprim-sulfametoxazol and tetracycline, respectively. Rank order of susceptibility for the quinolones was: gatifloxacin (98.4 percent) > levofloxacin (93.5 percent) > ciprofloxacin (64.5 percent). The rate of resistance to erythromycin (9.7 percent) was higher than that of other reports from Argentina. High-level resistance to gentamicin was not detected in any of the isolates. Based on our finding of 50 percent of GBS isolates with MIC to gentamicin equal o lower than 8 µg/ml, a concentration used in one of the selective media recommended for GBS isolation, we suggested, at least in our population, the use of nalidixic acid and colistin in selective media with the aim to improve the sensitivity of screening cultures for GBS carriage in women.


Esse estudo objetivou determinar os padrões de sensibilidade a antibióticos e as taxas de colonização de Streptococcus do grupo B (GBS) em uma população de mulheres grávidas. Entre janeiro de 2004 e dezembro de 2006, foram obtidos swabs vaginais-retais de 1105 mulheres no Hospital Dr. Ramon Madariaga, em Posadas, Missiones, Argentina. A positividade para GBS nas mulheres grávidas foi 7,6 por cento. Um total de 62 cepas de GBS foi selecionado ao acaso para testes in vitro de sensibilidade a penicilina G, ampicilina, tetraciclina, levofloxacina, gatifloxacina, ciprofloxacina, quinupristina-dalfopristina, linezolida, vancomicina, rifampicina, trimetoprim-sulfametoxazol, nitrofurantoína, gentamicina, clindamicina e eritromicina, e determinação dos fenótipos de resistência. Não foi encontrada resistência à penicilina, ampicilina, quinupristina-dalfopristina, linezolida e vancomicina. Entre as cepas, 96,8 por cento, 98,3 por cento, 46,8 por cento e 29,0 por cento foram sensíveis à rifampicina, nitrofurantoína, trimetoprim-sulfametoxazol e tetraciclina, respectivamente. Para as quinolonas, a ordem de sensibilidade foi: gatifloxacina (98,4 por cento) > levofloxacina (93,8 por cento) > ciprofloxacina (64,5 por cento). A taxa de resistência à eritromicina (9,7 por cento) foi superior a de outros relatos na Argentina. Nenhuma das cepas apresentou alto nível de resistência à gentamicina. Devido a 50 por cento das cepas de GBS terem apresentado MIC para gentamicina igual ou inferior a 8 mg/ml, correspondente à concentração usada em um dos meios seletivos recomendados para GBS, sugeriu-se ao menos em nossa população, o emprego de ácido nalidíxico e colistina em meios seletivos para melhorar a sensibilidade da triagem de culturas para GBS em mulheres grávidas.


Assuntos
Humanos , Feminino , Resistência Microbiana a Medicamentos , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/prevenção & controle , Resistência às Penicilinas , Streptococcus agalactiae/isolamento & purificação , Métodos , Taxa de Gravidez , Gestantes , Prevalência
5.
Braz J Microbiol ; 39(2): 245-50, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24031210

RESUMO

This study was performed to determine the susceptibility patterns and the colonization rate of Group B Streptococcus (GBS) in a population of pregnant women. From January 2004 to December 2006, vaginal-rectal swabs were obtained from 1105 women attending Dr. Ramón Madariaga Hospital, in Posadas, Misiones, Argentina. The carriage rate of GBS among pregnant women was 7.6%. A total of 62 GBS strains were randomly selected for in vitro susceptibility testing to penicillin G, ampicillin, tetracycline, levofloxacin, gatifloxacin, ciprofloxacin, quinupristin-dalfopristin, linezolid, vancomycin, rifampicin, trimethoprim- sulfametoxazol, nitrofurantoin, gentamicin, clindamycin and erythromycin, and determination of resistance phenotypes. No resistance to penicillin, ampicillin, quinupristin-dalfopristin, linezolid, and vancomycin was found. Of the isolates examined 96.8%, 98.3%, 46.8%, and 29.0% were susceptible to rifampicin, nitrofurantoin, trimethoprim-sulfametoxazol and tetracycline, respectively. Rank order of susceptibility for the quinolones was: gatifloxacin (98.4%) > levofloxacin (93.5%) > ciprofloxacin (64.5%). The rate of resistance to erythromycin (9.7%) was higher than that of other reports from Argentina. High-level resistance to gentamicin was not detected in any of the isolates. Based on our finding of 50% of GBS isolates with MIC to gentamicin equal o lower than 8 µg/ml, a concentration used in one of the selective media recommended for GBS isolation, we suggested, at least in our population, the use of nalidixic acid and colistin in selective media with the aim to improve the sensitivity of screening cultures for GBS carriage in women.

6.
Artigo em Inglês | VETINDEX | ID: vti-444231

RESUMO

This study was performed to determine the susceptibility patterns and the colonization rate of Group B Streptococcus (GBS) in a population of pregnant women. From January 2004 to December 2006, vaginal-rectal swabs were obtained from 1105 women attending Dr. Ramón Madariaga Hospital, in Posadas, Misiones, Argentina. The carriage rate of GBS among pregnant women was 7.6%. A total of 62 GBS strains were randomly selected for in vitro susceptibility testing to penicillin G, ampicillin, tetracycline, levofloxacin, gatifloxacin, ciprofloxacin, quinupristin-dalfopristin, linezolid, vancomycin, rifampicin, trimethoprim-sulfametoxazol, nitrofurantoin, gentamicin, clindamycin and erythromycin, and determination of resistance phenotypes. No resistance to penicillin, ampicillin, quinupristin-dalfopristin, linezolid, and vancomycin was found. Of the isolates examined 96.8%, 98.3%, 46.8%, and 29.0% were susceptible to rifampicin, nitrofurantoin, trimethoprim-sulfametoxazol and tetracycline, respectively. Rank order of susceptibility for the quinolones was: gatifloxacin (98.4%) > levofloxacin (93.5%) > ciprofloxacin (64.5%). The rate of resistance to erythromycin (9.7%) was higher than that of other reports from Argentina. High-level resistance to gentamicin was not detected in any of the isolates. Based on our finding of 50% of GBS isolates with MIC to gentamicin equal o lower than 8 µg/ml, a concentration used in one of the selective media recommended for GBS isolation, we suggested, at least in our population, the use of nalidixic acid and colistin in selective media with the aim to improve the sensitivity of screening cultures for GBS carriage in women.


Esse estudo objetivou determinar os padrões de sensibilidade a antibióticos e as taxas de colonização de Streptococcus do grupo B (GBS) em uma população de mulheres grávidas. Entre janeiro de 2004 e dezembro de 2006, foram obtidos swabs vaginais-retais de 1105 mulheres no Hospital Dr. Ramon Madariaga, em Posadas, Missiones, Argentina. A positividade para GBS nas mulheres grávidas foi 7,6%. Um total de 62 cepas de GBS foi selecionado ao acaso para testes in vitro de sensibilidade a penicilina G, ampicilina, tetraciclina, levofloxacina, gatifloxacina, ciprofloxacina, quinupristina-dalfopristina, linezolida, vancomicina, rifampicina, trimetoprim-sulfametoxazol, nitrofurantoína, gentamicina, clindamicina e eritromicina, e determinação dos fenótipos de resistência. Não foi encontrada resistência à penicilina, ampicilina, quinupristina-dalfopristina, linezolida e vancomicina. Entre as cepas, 96,8%, 98,3%, 46,8% e 29,0% foram sensíveis à rifampicina, nitrofurantoína, trimetoprim-sulfametoxazol e tetraciclina, respectivamente. Para as quinolonas, a ordem de sensibilidade foi: gatifloxacina (98,4%) > levofloxacina (93,8%) > ciprofloxacina (64,5%). A taxa de resistência à eritromicina (9,7%) foi superior a de outros relatos na Argentina. Nenhuma das cepas apresentou alto nível de resistência à gentamicina. Devido a 50% das cepas de GBS terem apresentado MIC para gentamicina igual ou inferior a 8 mg/ml, correspondente à concentração usada em um dos meios seletivos recomendados para GBS, sugeriu-se ao menos em nossa população, o emprego de ácido nalidíxico e colistina em meios seletivos para melhorar a sensibilidade da triagem de culturas para GBS em mulheres grávidas.

7.
Lupus ; 16(6): 430-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17664234

RESUMO

To evaluate cervicovaginal cytology in adolescents with juvenile systemic lupus erythematosus (JSLE) and to compare them to controls. Fifty-two female adolescents with JSLE (ACR criteria) were compared to 52 age-matched healthy controls. All Pap smears were evaluated by the same cytopathologist blinded to gynecology examination (Bethesda 2001). The mean age of JSLE patients and controls were similar (16.17 +/- 1.94 versus 16.13 +/- 2.16 years, P = 0.92). The cervicovaginal cytology was found to be similar in both groups, although sexual intercourses in the last month were less frequent in JSLE than controls (23% versus 59.6%, P = 0.0003). Only one patient (2%) with JSLE versus two controls (4%) had cervical dysplasia (LGSIL) and human papilomavirus (P = 1.0). Candida spp vaginitis was observed in seven JSLE (14%) versus none in controls (P = 0.012) and was associated with immunosuppressive drugs (P = 0.01) and high dose of prednisone (P = 0.002). Of interest, inflammatory cervicovaginal cytology was observed in 21 (60%) of patients with SLEDAI > or = 4 and only four (23%) of those with SLEDAI < 4 (P = 0.001). Likewise, a higher frequency of inflammatory changes was also observed in virgin JSLE (57% versus 8%, P = 0.005). Our findings supports the notion that female genital tract may be a potential target organ in SLE since cervical inflammation is associated to disease activity independently of sexual activity.


Assuntos
Colo do Útero/patologia , Lúpus Eritematoso Sistêmico/patologia , Lúpus Eritematoso Sistêmico/fisiopatologia , Vagina/patologia , Adolescente , Candidíase , Criança , Condiloma Acuminado/complicações , Condiloma Acuminado/diagnóstico , Feminino , Humanos , Inflamação/patologia , Lúpus Eritematoso Sistêmico/complicações , Teste de Papanicolaou , Índice de Gravidade de Doença , Vagina/microbiologia , Vagina/virologia , Esfregaço Vaginal , Vaginose Bacteriana/complicações , Vaginose Bacteriana/microbiologia
8.
Protoplasma ; 228(4): 189-99, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16983486

RESUMO

A comparative analysis of the effect of two compounds, dibutyryl-cyclic-AMP (dbcAMP) and latrunculin B, on the morphology and ultrastructure of the dimorphic fungus Mucor rouxii under aerobic growth conditions is presented. dbcAMP acts through the sustained activation of protein kinase A, and latrunculin B through the disruption of the actin cytoskeleton. Upon addition of these compounds to the growth medium at any stage of the germination process, cells lost polarised growth and switched to isodiametric growth. The effect was reversible. The morphologies, visualised by light microscopy or scanning electron microscopy (SEM), were alike. A switch from a rough to a smooth surface was observed by SEM when cells were repolarised by removal of the added compound. Ultrastructural changes under both conditions, as observed by transmission electron microscopy, were similar, the main feature being the enlargement of the cell wall, with irregular depositions, and detachment from the cell membrane. dbcAMP-treated cells showed a decrease in the number of glycogen granules compared with control and latrunculin B-treated cells. F-actin staining with fluorescein isothiocyanate-phalloidin showed that both dbcAMP- and latrunculin B-treated cells displayed a much lower fluorescence than control cells, with only a few pale plaques. The results suggest that the sustained activation of protein kinase A, which impairs polarised growth, might exert its effect through a modification of actin cytoskeleton organisation, very probably also involving an integrinlike pathway, as judged by the cell wall detachment and loss of cell adhesiveness of the dbcAMP-treated isodiametric cells.


Assuntos
Actinas/metabolismo , AMP Cíclico/farmacologia , Citoesqueleto/metabolismo , Mucor/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Bucladesina/farmacologia , AMP Cíclico/análogos & derivados , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência/métodos , Mucor/metabolismo , Mucor/ultraestrutura , Tiazolidinas/farmacologia
9.
Med Microbiol Immunol ; 195(2): 85-92, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16220309

RESUMO

In this study, we describe the isolation and partial characterization of a Pixuna virus receptor, which is a component of a plasma membrane fraction of chicken embryo fibroblast (CEF). Polyclonal antiserum was prepared from rabbits immunized with the membrane fraction. Said polyclonal antiserum reacted in a similar way as monoclonal antibodies raised against the membrane fraction. Both antisera were able to prevent CEF and Vero cells from infection with Pixuna virus. Immunofluorescence studies suggested that the receptors found in the fibroblasts and in the Vero cells shared at least some epitopes. The Western blot analysis of the purified membrane fraction antigens, which reacted with the monoclonal and polyclonal antibodies, detected a double band with a molecular mass of approximately 60 kDa. Not only immunofluorescence staining but also electron and immunoelectron microscopy studies evidenced the receptor localization in the plasma membrane. In this manner, we reported the isolation and partial characterization of a new Pixuna virus receptor in the plasma membrane of chicken embryo fibroblasts in culture. The data obtained demonstrated the receptor significance for the penetration of Pixuna virus into fibroblasts and mammalian cell and the related importance of designing new antiviral drugs by blocking the mechanism of receptor penetration of the virus into the cells.


Assuntos
Alphavirus , Fibroblastos/química , Receptores Virais/isolamento & purificação , Alphavirus/metabolismo , Animais , Western Blotting , Células Cultivadas , Embrião de Galinha , Chlorocebus aethiops , Quimotripsina/metabolismo , Fibroblastos/virologia , Microscopia de Fluorescência , Peso Molecular , Receptores Virais/metabolismo , Tripsina/metabolismo , Células Vero , Ensaio de Placa Viral
10.
Phytomedicine ; 11(2-3): 213-23, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15070175

RESUMO

The genus Uncaria Schreber (Rubiaceae) includes species that are widely distributed in tropical areas. The inner bark of the stems and leaves of two native species of South America, Uncaria tomentosa (Willd. ex Roemer & Schultes) DC., and Uncaria guianensis (Aublet) J. F. Gmelin, "cat's claw" are used in either folk medicine or in procuring phytotherapeutic drugs. These species contain about sixty active substances which are being tested widely for possible medicinal value. The following applications are considered: peptic ulcer, rheumatism, tumours, antiinflammatory effect, inflammation, diabetes and as general tonic. Currently, Uncaria tomentosa is in demand as tea, tablets or capsules in more than 30 countries outside Perú, as well as inside the country. Pharmacognosy studies are required to determine the comparative morphoanatomical and micrographic features for identification and quality control purposes. Several microscopic parameters, including phloem fibers, calcium oxalate crystals, starch granules, trichomes, and foliar architecture should be considered. The aim of our work is to analyse comparative morphoanatomical and micrographic features which might provide assistance in the identification, analysis and standardization of Uncaria tomentosa (Willd. ex Roemer & Schultes) DC. and Uncaria guianensis (Aublet) J. F. Gmelin stem bark and leaves in order to obtain phytotherapeutic drugs, and of the crude drug as well.


Assuntos
Fitoterapia , Uncaria/anatomia & histologia , Unha-de-Gato/anatomia & histologia , Humanos , Casca de Planta , Folhas de Planta
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