RESUMO
Streptococcus mutans is specifically suppressed by intensive treatment with chlorhexidine gel, but the time for recolonization and the effect on other oral bacteria are not totally clear. In this study, recolonization of mutans streptococci was evaluated in nine healthy adult volunteers, who were highly colonized with this microorganism. Stimulated saliva was collected before (baseline) and at 1, 7, 14, 21 and 28 days after application of 1% chlorhexidine gel on volunteers' teeth for two consecutive days. On each day, the gel was applied using disposable trays for 3 x 5 min with intervals of 5 min between each application. Saliva was plated on blood agar to determine total microorganisms (TM); on mitis salivarius agar to determine total streptococci (TS) and on mitis salivarius agar plus bacitracin to determine mutans streptococci (MS). Chlorhexidine was capable of reducing the counts of MS and the proportion of MS with regard to total microorganisms (%MS/TM) (p<0.05), but these values did not differ statistically from baseline (p>0.05) after 14 days for MS and 21 days for %MS/TM. The counts of TM and TS and the proportion of MS to total streptococci did not differ statistically from baseline (p>0.05) after chlorhexidine treatment. The results suggest that the effect of chlorhexidine gel treatment on suppression of mutans streptococci is limited to less than a month in highly colonized individuals.
Streptococcus mutans é especificamente suprimido pelo tratamento intensivo com clorexidina em gel, mas o tempo de recolonização e o efeito em outras bactérias orais não está totalmente claro. Nesse estudo, a recolonização de estreptococos do grupo mutans foi avaliado em nove voluntários adultos saudáveis, os quais eram altamente colonizados por esse microrganismo. Saliva estimulada foi coletada antes (baseline) e 1, 7, 14, 21 e 28 dias após a aplicação de clorexidina em gel a 1% nos dentes dos voluntários por dois dias consecutivos. Em cada dia, o gel foi aplicado utilizando moldeiras descartáveis por 3 x 5 min com intervalos de 5 min entre cada aplicação. A saliva foi inoculada em ágar sangue para determinação dos microrganismos totais (MT); em mitis salivarius ágar para determinação dos estreptococos totais (ET) e em meio mitis salivarius com bacitracina para determinar a contagem de estreptococos do grupo mutans (EGM). O tratamento com clorexidina foi capaz de reduzir as contagens de EGM e a proporção de EGM em relação aos microrganismos totais (%EGM/MT) (p<0,05), mas esses valores não diferiram estatisticamente do baseline (p>0,05) após 14 dias para EGM e 21 dias para %EGM/MT. As contagens de MT e ET e a proporção de EGM em relação a estreptococos totais não difereriram estatisticamente do baseline (p>0,05) após o tratamento com clorexidina. Os resultados sugerem que o efeito do tratamento com clorexidina em gel na supressão de estreptococos do grupo mutans é limitado a menos de um mês em indivíduos altamente colonizados. .
Assuntos
Animais , Masculino , Camundongos , Adenocarcinoma/tratamento farmacológico , Antineoplásicos/farmacocinética , Bromodesoxiuridina/análogos & derivados , Floxuridina/farmacocinética , Fluoruracila/sangue , Antineoplásicos/sangue , Antineoplásicos/uso terapêutico , Bromodesoxiuridina/administração & dosagem , Bromodesoxiuridina/sangue , Bromodesoxiuridina/farmacocinética , Bromodesoxiuridina/uso terapêutico , Cromatografia Líquida de Alta Pressão , Sinergismo Farmacológico , Floxuridina/administração & dosagem , Floxuridina/sangue , Floxuridina/uso terapêutico , Meia-Vida , Transplante de Neoplasias , Espectrofotometria UltravioletaRESUMO
The present study evaluated the effect of FSH treatment on ovarian cell proliferation in the hypophysectomized chicken embryo. Hypophysectomy (Hx) was performed by the partial decapitation technique. Two series of experiments were performed: (a) Hx embryos were treated at 8 days of development with recombinant human FSH (rhFSH) and evaluated at 9 days by measuring BrdU incorporation; (b) Hx embryos were injected with rhFSH and rhCG at 9 days of development and the proliferation rate was measured at 13 days. The presence of mRNA for FSHR and LHR in the ovary of control and Hx embryos was demonstrated by RT-PCR analysis. There was a decrease in the percentage of BrdU labeled cells in the absence of hypophysis at 9 and 13 days of incubation. The decrease was reversed with rhFSH treatment. This effect was observed in the ovarian surface epithelium and the somatic cells of the cortex and the medulla in the 9-day-old embryo. Moreover, the number of somatic, steroidogenic, and germ cells was reduced at 13 days of incubation in the Hx embryo; when treated with rhFSH the number of cells increased to the level of controls. In another experiment, ovaries of 9-day-old chicken embryos were organ cultured for 48 h in a serum-free medium with rhFSH and rhCG separately. The proliferation index was incremented by rhFSH compared to control and rhCG-treated embryos. Therefore, FSH stimulates somatic cell proliferation in the chicken embryo ovary as early as 9 days of development.
Assuntos
Embrião de Galinha/embriologia , Hormônio Foliculoestimulante/farmacologia , Hipofisectomia , Ovário/citologia , Ovário/embriologia , Animais , Antimetabólitos/farmacocinética , Bromodesoxiuridina/farmacocinética , Divisão Celular/efeitos dos fármacos , Galinhas , Meios de Cultura Livres de Soro/farmacologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Feminino , Técnicas de Cultura de Órgãos , Ovário/efeitos dos fármacos , RNA Mensageiro/metabolismo , Receptores do FSH/genética , Receptores do FSH/metabolismo , Receptores do LH/genética , Receptores do LH/metabolismo , Proteínas Recombinantes/farmacologiaRESUMO
Twenty-one-day-old Wistar rats were fed a diet containing 0.6% cuprizone for 2 weeks. Studies carried out after withdrawal of cuprizone showed histological evidences of marked demyelination in the corpus callosum. Biochemical studies of isolated myelin showed a marked decrease in myelin proteins, phospholipids, and galactocerebrosides as well as a marked decrease in myelin yield. Treatment of these animals with a single intracranial injection of 350 ng of apotransferrin at the time of withdrawal of cuprizone induced a marked increase in myelin deposition resulting in a significantly improved remyelination, evaluated by histological, immunocytochemical, and biochemical parameters, in comparison to what was observed in spontaneous recovery. Immunocytochemical studies of cryotome sections to analyze developmental parameters of the oligodendroglial cell population at the time of termination of cuprizone and at different times thereafter showed that in the untreated animals, there was a marked increase in the number of NG2-BrdU-positive precursor cells together with a marked decrease in MBP expression at the peak of cuprizone-induced demyelination. As expected, the amount of precursor cells decreased markedly during spontaneous remyelination and was accompanied by an increase in MBP reactivity. In the apotransferrin-treated animals, these phenomena occurred much faster, and remyelination was much more efficient than in the untreated controls. The results of this study suggest that apotransferrin is a very active promyelinating agent which could be important for the treatment of certain demyelinating conditions.
Assuntos
Apoproteínas/uso terapêutico , Cuprizona , Doenças Desmielinizantes/tratamento farmacológico , Recuperação de Função Fisiológica/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Transferrina/uso terapêutico , Análise de Variância , Animais , Animais Recém-Nascidos , Antígenos/metabolismo , Apoproteínas/farmacologia , Encéfalo/patologia , Bromodesoxiuridina/farmacocinética , Antígeno CD11b/metabolismo , Contagem de Células/métodos , Proteínas do Citoesqueleto/metabolismo , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/fisiopatologia , Interações Medicamentosas , Galactolipídeos/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Imuno-Histoquímica/métodos , Indóis , Proteína Básica da Mielina/metabolismo , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/patologia , Proteoglicanas/metabolismo , Ratos , Ratos Wistar , Regeneração/fisiologia , Fatores de Tempo , Transferrina/farmacologiaRESUMO
We present a modified protocol for the immunocytochemical identification of 5-bromo-2'-deoxyuridine (BrdU) as an indicator of cell replication in different tissues of the toad, Bufo arenarum Hensel. Animals were sacrificed 60 min after BrdU (5 mg/100 g body weight) was injected into the dorsal lymph sac. The tissues were fixed in Carnoy's fluid and stained by the immunoperoxidase method using an anti-BrdU monoclonal antibody. This protocol can be used safely for the study of cell replication in toads and other Anura amphibia.