RESUMO
Objective: To evaluate the ability of lactic acid bacteria (LAB) strains isolated from fermented mustard to lower the cholesterol in vitro.Methods:The ability of 50 LAB strains isolated from fermented mustard on lowering cholesterol in vitro was determined by modified o-phtshalaldehyde method. The LAB isolates were analyzed for their resistance to acid and bile salt. Strains with lowering cholesterol activity, were determined adherence to Caco-2 cells. Results: Strain B0007, B0006 and B0022 assimilated more cholesterol than BCRC10474 and BCRC 17010. The isolated strains showed tolerance to pH 3.0 for 3 h despite variations in the degree of viability and bile-tolerant strains, with more than 108 CFU/mL after incubation for 24 h at 1%oxigall in MRS. In addition, strain B0007 and B0022 identified as Lactobacillus plantarum with 16S rDNA sequences were able to adhere to the Caco-2 cell lines.Conclusions:These strains B0007 and B0022 may be potential functional sources for cholesterol-lowering activities as well as adhering to Caco-2 cell lines.
Assuntos
Complicações Pós-Operatórias/diagnóstico por imagem , Edema Pulmonar/diagnóstico por imagem , Apneia Obstrutiva do Sono/cirurgia , Adulto , Humanos , Masculino , Complicações Pós-Operatórias/terapia , Edema Pulmonar/etiologia , Edema Pulmonar/terapia , Radiografia , Procedimentos de Cirurgia Plástica , Respiração Artificial , Resultado do TratamentoRESUMO
Balancing self-renewal and differentiation of stem cells is an important issue in stem cell and cancer biology. Recently, the Drosophila neuroblast (NB), neural stem cell has emerged as an excellent model for stem cell self-renewal and tumorigenesis. It is of great interest to understand how defects in the asymmetric division of neural stem cells lead to tumor formation. Here, we review recent advances in asymmetric division and the self-renewal control of Drosophila NBs. We summarize molecular mechanisms of asymmetric cell division and discuss how the defects in asymmetric division lead to tumor formation. Gain-of-function or loss-of-function of various proteins in the asymmetric machinery can drive NB overgrowth and tumor formation. These proteins control either the asymmetric protein localization or mitotic spindle orientation of NBs. We also discuss other mechanisms of brain tumor suppression that are beyond the control of asymmetric division.
Assuntos
Neoplasias Encefálicas/metabolismo , Células-Tronco Neurais/citologia , Animais , Neoplasias Encefálicas/patologia , Diferenciação Celular/fisiologia , Divisão Celular/fisiologia , Drosophila , Proteínas de Drosophila/metabolismoRESUMO
How a cell decides to self-renew or differentiate is a critical issue in stem cell and cancer biology. Atypical protein kinase C (aPKC) promotes self-renewal of Drosophila larval brain neural stem cells, neuroblasts. However, it is unclear how aPKC cortical polarity and protein levels are regulated. Here, we have identified a zinc-finger protein, Zif, which is required for the expression and asymmetric localization of aPKC. aPKC displays ectopic cortical localization with upregulated protein levels in dividing zif mutant neuroblasts, leading to neuroblast overproliferation. We show that Zif is a transcription factor that directly represses aPKC transcription. We further show that Zif is phosphorylated by aPKC both in vitro and in vivo. Phosphorylation of Zif by aPKC excludes it from the nucleus, leading to Zif inactivation in neuroblasts. Thus, reciprocal repression between Zif and aPKC act as a critical regulatory mechanism for establishing cell polarity and controlling neuroblast self-renewal.
Assuntos
Polaridade Celular/fisiologia , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/embriologia , Células-Tronco Neurais , Proteína Quinase C/metabolismo , Fatores de Transcrição/metabolismo , Animais , Proteínas de Drosophila/genética , Drosophila melanogaster/fisiologia , Células-Tronco Neurais/citologia , Células-Tronco Neurais/fisiologia , Fosforilação , Proteína Quinase C/genética , Fatores de Transcrição/genéticaRESUMO
Drosophila larval brain neural stem cells, also known as neuroblasts, divide asymmetrically to generate a self-renewing neuroblast and a ganglion mother cell (GMC) that divides terminally to produce two differentiated neurons or glia. Failure of asymmetric cell division can result in hyperproliferation of neuroblasts, a phenotype resembling brain tumors. Here we have identified Drosophila Protein phosphatase 2A (PP2A) as a brain tumor-suppressor that can inhibit self-renewal of neuroblasts. Supernumerary larval brain neuroblasts are generated at the expense of differentiated neurons in PP2A mutants. Neuroblast overgrowth was observed in both dorsomedial (DM)/posterior Asense-negative (PAN) neuroblast lineages and non-DM neuroblast lineages. The PP2A heterotrimeric complex, composed of the catalytic subunit (Mts), scaffold subunit (PP2A-29B) and a B-regulatory subunit (Tws), is required for the asymmetric cell division of neuroblasts. The PP2A complex regulates asymmetric localization of Numb, Pon and Atypical protein kinase C, as well as proper mitotic spindle orientation. Interestingly, PP2A and Polo kinase enhance Numb and Pon phosphorylation. PP2A, like Polo, acts to prevent excess neuroblast self-renewal primarily by regulating asymmetric localization and activation of Numb. Reduction of PP2A function in larval brains or S2 cells causes a marked decrease in Polo transcript and protein abundance. Overexpression of Polo or Numb significantly suppresses neuroblast overgrowth in PP2A mutants, suggesting that PP2A inhibits excess neuroblast self-renewal in the Polo/Numb pathway.
Assuntos
Drosophila melanogaster/citologia , Neurônios/fisiologia , Proteína Fosfatase 2/metabolismo , Células-Tronco/fisiologia , Animais , Células Cultivadas , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/enzimologia , Drosophila melanogaster/fisiologia , Hormônios Juvenis/genética , Hormônios Juvenis/metabolismo , Neurônios/citologia , Proteína Fosfatase 2/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Fuso Acromático/metabolismo , Fuso Acromático/ultraestrutura , Células-Tronco/citologiaRESUMO
The F-actin-based molecular motor myosin II is involved in a variety of cellular processes such as muscle contraction, cell motility, and cytokinesis. In recent years, a family of myosin II-specific cochaperones of the UCS family has been identified from work with yeasts, fungi, worms, and humans. Biochemical analyses have shown that a complex of Hsp90 and the Caenorhabditis elegans UCS domain protein UNC-45 prevent myosin head aggregation, thereby allowing it to assume a proper structure. Here we demonstrate that a temperature-sensitive mutant of the fission yeast Hsp90 (Swo1p), swo1-w1, is defective in actomyosin ring assembly at the restrictive temperature. Two alleles of swo1, swo1-w1 and swo1-26, showed synthetic lethality with a specific mutant allele of the fission yeast type II myosin head, myo2-E1, but not with two other mutant alleles of myo2 or with mutations affecting 14 other genes important for cytokinesis. swo1-w1 also showed a strong genetic interaction with rng3-65, a gene encoding a mutation in the fission yeast UCS domain protein Rng3p, which has previously been shown to be important for myosin II assembly. A similar deleterious effect was found when myo2-E1, swo1-w1, and rng3-65 were pharmacologically treated with geldanamycin to partially inhibit Hsp90 function. Interestingly, Swo1p-green fluorescent protein is detected at the improperly assembled actomyosin rings in myo2-E1 but not in a wild-type strain. Yeast two-hybrid and coimmunoprecipitation analyses verified interactions between Rng3p and the myosin head domain as well as interactions between Rng3p and Swo1p. Our analyses of Myo2p, Swo1p, and the UCS domain protein Rng3p establish that Swo1p and Rng3p collaborate in vivo to modulate myosin II function.
Assuntos
Proteínas do Citoesqueleto/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Miosina Tipo II/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Schizosaccharomyces/metabolismo , Alelos , Animais , Benzoquinonas , Proteínas do Citoesqueleto/genética , Citoesqueleto/metabolismo , Inibidores Enzimáticos/metabolismo , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/genética , Humanos , Lactamas Macrocíclicas , Cadeias Pesadas de Miosina/genética , Miosina Tipo II/genética , Ligação Proteica , Estrutura Terciária de Proteína , Quinonas/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Schizosaccharomyces/citologia , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/genética , Temperatura , Técnicas do Sistema de Duplo-HíbridoRESUMO
En 1945, Foote y Stewart plantearon que el antecedente más frecuente de cáncer en un seno es haber tenido una neoplasia en el seno contrario. Se realizó un estudio sobre los casos de cáncer de mama bilateral atendidos en nuestro servicio entre 1982 y 2003. El universo está compuesto por 25 pacientes que fueron atendidas en los últimos 20 años por cáncer de mama bilateral, la mayoría de ellos metacrónicos (21 casos). En cada caso se analizó edad, etapas clínicas al momento del diagnóstico, tratamiento utilizado, tipo histológico y evolución, entre otras variables. Se observó la mayor incidencia de esta enfermedad en la 5ta y 6ta décadas de la vida, con predominio de los tumores en etapa II. El tipo de operación más realizado fue la mastectomía radical modificada de Patey y prevalecieron las técnicas más conservadores en la segunda operación. Siete de las pacientes fallecieron por la enfermedad. El pronóstico de las mujeres con cáncer de mama bilateral suele ser favorable y depende de la etapa de desarrollo de éste al momento del diagnóstico. El tratamiento del segundo primario fue más conservador que el primero. El seguimiento estricto y el uso de la ingeniería genética son elementos fundamentales para el diagnóstico precoz(AU)
Assuntos
Neoplasias da Mama/diagnósticoRESUMO
Entre las causas pulmonares de disnea, ninguna se compara , ni en morbilidad, nio en mortalidad, con la enfermedad pulmonar obstructiva crònica, la cual constituye en el adulto la quinta causa de muerte y la primera de invalidez. La enfermedad bullosa presenta complicaciones como infecciòn, neumotòrax, hemorragia, insuficiencia respiratoria crònica y càncer de pulmòn. En el articulo se ofrecen experiencias de un mèdico costarricense de origen taiwanès, Dr. Kai Cheng Hung Chang, junto a su colectivo de profesores, en la lucha contra la sed de aire(AU)
Assuntos
Humanos , Reabilitação , Pneumotórax , Enfisema Pulmonar/cirurgia , PneumonectomiaRESUMO
Entre las causas pulmonares de disnea, ninguna se compara , ni en morbilidad, nio en mortalidad, con la enfermedad pulmonar obstructiva crònica, la cual constituye en el adulto la quinta causa de muerte y la primera de invalidez. La enfermedad bullosa presenta complicaciones como infecciòn, neumotòrax, hemorragia, insuficiencia respiratoria crònica y càncer de pulmòn. En el articulo se ofrecen experiencias de un mèdico costarricense de origen taiwanès, Dr. Kai Cheng Hung Chang, junto a su colectivo de profesores, en la lucha contra la sed de aire
Assuntos
Humanos , Pneumonectomia , Pneumotórax , Enfisema Pulmonar , ReabilitaçãoRESUMO
En 1945, Foote y Stewart plantearon que el antecedente más frecuente de cáncer en un seno es haber tenido una neoplasia en el seno contrario. Se realizó un estudio sobre los casos de cáncer de mama bilateral atendidos en nuestro servicio entre 1982 y 2003. Métodos: El universo de nuestro trabajo está compuesto por 25 pacientes que fueron atendidas en los últimos 20 años por cáncer de mama bilateral, la mayoría de ellos metacrónicos (21 casos). En cada caso se analizó edad, etapas clínicas al momento del diagnóstico, tratamiento utilizado, tipo histológico y evolución, entre otras variables. Resultados: Se observó la mayor incidencia de esta enfermedad en la 5ta. y 6ta. décadas de la vida, con predominio de los tumores en etapa II. El tipo de operación más realizado fue la mastectomía radical modificada de Patey y prevalecieron las técnicas más conservadores en la segunda operación. Siete de las pacientes fallecieron por la enfermedad. Conclusiones: El pronóstico de las mujeres con cáncer de mama bilateral suele ser favorable y depende de la etapa de desarrollo de éste al momento del diagnóstico. El tratamiento del segundo primario fue más conservador que el primero. El seguimiento estricto y el uso de la ingeniería genética son elementos fundamentales para el diagnóstico precoz(AU)
In 1945, Foote and Stewart said: the most frequent antecedent of cancer in a breast is having had a neoplasia in the other breast. A study of the cases of bilateral breast cancer seen in our service between 1982 and 2003 was conducted. Methods: The universe of our work was composed of 25 patients attended in the last 20 years due to bilateral breast cancer. Most of them were metachronic (21 cases). Age, clinical stages at the time of diagnosis, treatment used, histological type and evolution, among other variables, were analyzed. Results: the highest incidence of this disease was observed in the 5th and 6th decades of life, with predominance of stage II tumors. Patev's modified radical mastectomy was the most common operation. The most conservative techniques prevailed in the second operation. Seven of the patients died as a result of the disease. Conclusions: the prognosis of women with bilateral breast cancer is usually favorable and it depends on its development stage at the time of the diagnosis. The treatment of the second was more conservative than the first one. The strict follow-up and the use of genetic engineering are fundamental elements for the early diagnosis(AU)