ABSTRACT
BACKGROUND: Loss or mutations of the BRCA1 gene are associated with increased risk of breast and ovarian cancers and with prostate cancer (PCa) aggressiveness. Previously, we identified GADD153 as a target of BRCA1 protein, which increases doxorubicin sensitivity in human p53 -/- PCa cells (PC3). Considering that p53 is a crucial target in cancer therapy, in this work we investigated p53 role in the regulation of transcription of GADD153. METHODS: We performed reverse transcription quantitative PCR (RT-qPCR), western blot and luciferase assays to analyze GADD153 and/or BRCA1 expression in response to ultraviolet or doxorubicin exposure in PC3 p53 stable-transfected cells and LNCaP (p53+/+) cells. BRCA1 protein recruitment to GADD153 promoter was studied by chromatin immunoprecipitation-qPCR. To assess expression of BRCA1 and/or p53 target genes, we used a panel of stable-transfected PCa cell lines. We finally analyzed these genes in vivo using BRCA1-depleted PCa xenograft models. RESULTS: We found that GADD153 was highly induced by doxorubicin in PC3 cells; however, this response was totally abolished in LNCaP (p53wt) and in p53-restituted PC3 cells. Furthermore, BRCA1 protein associates to GADD153 promoter after DNA damage in the presence of p53. Additionally, we demonstrated that BRCA1 and/or p53 modulate genes involved in DNA damage and cell cycle regulation (cyclin D1, BLM, BRCA2, DDB2, p21(WAF1/CIP1), H3F3B, GADD153, GADD45A, FEN1, CCNB2), EMT (E-cadherin, ß-catenin, vimentin, fibronectin, slug, snail) and Hedgehog pathways (SHH, IHH, DHH, Gli1, PATCH1). Furthermore, xenograft studies demonstrated that BRCA1 knockdown in PC3 cells increased tumor growth and modulated these genes in vivo. CONCLUSIONS: Although BRCA1 induces GADD153 in a p53 independent manner, p53 abolished GADD153 induction in response to DNA damage. In addition, several important PCa targets are modulated by BRCA1 and p53. Altogether, these data might be important to understand the therapy response of PCa patients.
Subject(s)
BRCA1 Protein/metabolism , Prostatic Neoplasms/metabolism , Tumor Suppressor Protein p53/metabolism , Animals , BRCA1 Protein/genetics , Cell Cycle/genetics , Cell Line, Tumor , DNA Damage , Hedgehogs/genetics , Hedgehogs/metabolism , Heterografts , Humans , Male , Mice , Prostatic Neoplasms/genetics , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction , Transcription Factor CHOP/metabolism , Transcription, Genetic , Tumor Suppressor Protein p53/geneticsABSTRACT
Human Metapneumovirus (hMPV) is a recently reported agent of acute infection in the respiratory tract. It has been found in children as well as in young adults and elders. The clinical manifestations produced by hMPV are indistinguishable from those by common respiratory virus, and can evolve from asymptomatic infection into severe pneumonia. On the other hand, some authors have described cases of bronchial asthma exacerbation associated with hMPV infection. In this work we report a case of a child who presented a severe bronchial asthmatic crisis with a suspected viral associated infection. Immunofluorescence tests yielded negative results for sincitial respiratory virus, adenovirus, a-b influenza virus and parainfluenza 1, 2, 3, virus. In an attempt to detect the presence of hMPV, a RT-PCR was carried out to amplify sequences from both N and F genes. Using this approach, a positive result for hMPV was obtained. To our knowledge, this is the first description of a case of asthma exacerbation associated to hMPV in our region. In addition, these results are similar to previous reports where it was hypothesized that, like RSV, hMPV can trigger a respiratory chronic disease as asthma.
Subject(s)
Asthma/virology , Metapneumovirus , Paramyxoviridae Infections/complications , Acute Disease , Child, Preschool , Humans , Male , Metapneumovirus/isolation & purification , Severity of Illness IndexABSTRACT
The aim of the present work was to evaluate the usefulness of a simplified method for DNA extraction coupled to a nested-PCR protocol, based on the amplification of pneumolysin gene fragments for the diagnosis of pneumococcal pneumonia in pediatric patients with clinical and radiological evidence of bacterial infection. Bacterial DNA was extracted from sera by boiling and used without further purification in the PCR for the pneumolysin gene. None toxic reagents were used and the necessary steps to obtain the DNA were left at a minimum; furthermore, it overcomes the use of expensive commercial kits for DNA purification. The total procedure can be completed the same day of sampling and, most important, it avoids the use of sophisticated technology. Both in vitro analytical specificity and sensitivity (10 CFU/ml) of the assay were similar to those previously reported. When clinical samples were tested, the rate of positivity was shown to be 83.3% and 71% in pediatric patients with positive (group a) and negative blood cultures (group b), respectively. In group a, DNA detection was successful in samples from children without treatment or with less than 48 h of antibiotic therapy. None amplification was obtained from sera patients with viral infection or in samples from healthy controls. The application of the strategy described in this paper substantially seems to improve the diagnostic process in a determinate group: blood culture-negative children with pneumonia.
El objetivo del presente trabajo fue evaluar la utilidad de un método simplificado para extracción de ADN, acoplado a un protocolo de PCR anidada, basada en la amplificación de fragmentos del gen de la neumolisina para el diagnóstico de neumonía neumocócica en niños con evidencias clínicas y radiológicas de infección bacteriana. El ADN bacteriano fue extraído del suero por calentamiento y utilizado en la PCR para el gen de la neumolisina sin purificación posterior. Para la obtención de ADN no se utilizan reactivos tóxicos ni costosos "kits" comerciales. El procedimiento completo puede ser realizado en el día y lo que es más importante, evita el uso de tecnología sofisticada. La especificidad analítica in vitro y la sensibilidad (10 UFC/ml) del ensayo fueron similares a lo hallado en publicaciones anteriores. El porcentaje de muestras positivas fue del 83,3% y del 71% en los pacientes con hemocultivos positivos (grupo a) y negativos (grupo b), respectivamente. En el grupo a, sólo se obtuvieron resultados positivos mediante la PCR anidada en los pacientes no tratados o con menos de 48 hs de tratamiento antibiótico. No se obtuvieron señales de amplificación en los sueros de los pacientes con infecciones virales ni en las muestras del grupo control. La aplicación de la estrategia descripta incrementa la posibilidad diagnóstica de neumonía neumocócica en niños con hemocultivos negativos.
Subject(s)
Child, Preschool , Female , Humans , Infant , Male , Community-Acquired Infections/microbiology , DNA, Bacterial/isolation & purification , Pneumonia, Pneumococcal/microbiology , Polymerase Chain Reaction/methods , Streptococcus pneumoniae/isolation & purification , Bacteremia/microbiology , Community-Acquired Infections/diagnosis , Diagnosis, Differential , DNA, Bacterial/blood , DNA, Bacterial/genetics , Pneumonia, Bacterial/diagnosis , Pneumonia, Pneumococcal/diagnosis , Pneumonia, Viral/diagnosis , Sensitivity and Specificity , Streptococcus pneumoniae/geneticsABSTRACT
The aim of the present work was to evaluate the usefulness of a simplified method for DNA extraction coupled to a nested-PCR protocol, based on the amplification of pneumolysin gene fragments for the diagnosis of pneumococcal pneumonia in pediatric patients with clinical and radiological evidence of bacterial infection. Bacterial DNA was extracted from sera by boiling and used without further purification in the PCR for the pneumolysin gene. None toxic reagents were used and the necessary steps to obtain the DNA were left at a minimum; furthermore, it overcomes the use of expensive commercial kits for DNA purification. The total procedure can be completed the same day of sampling and, most important, it avoids the use of sophisticated technology. Both in vitro analytical specificity and sensitivity (10 CFU/ml) of the assay were similar to those previously reported. When clinical samples were tested, the rate of positivity was shown to be 83.3% and 71% in pediatric patients with positive (group a) and negative blood cultures (group b), respectively. In group a, DNA detection was successful in samples from children without treatment or with less than 48 h of antibiotic therapy. None amplification was obtained from sera patients with viral infection or in samples from healthy controls. The application of the strategy described in this paper substantially seems to improve the diagnostic process in a determinate group: blood culture-negative children with pneumonia.
Subject(s)
Community-Acquired Infections/microbiology , DNA, Bacterial/isolation & purification , Pneumonia, Pneumococcal/microbiology , Polymerase Chain Reaction/methods , Streptococcus pneumoniae/isolation & purification , Bacteremia/microbiology , Child, Preschool , Community-Acquired Infections/diagnosis , DNA, Bacterial/blood , DNA, Bacterial/genetics , Diagnosis, Differential , Female , Humans , Infant , Male , Pneumonia, Bacterial/diagnosis , Pneumonia, Pneumococcal/diagnosis , Pneumonia, Viral/diagnosis , Sensitivity and Specificity , Streptococcus pneumoniae/geneticsABSTRACT
The aim of the present work was to evaluate the usefulness of a simplified method for DNA extraction coupled to a nested-PCR protocol, based on the amplification of pneumolysin gene fragments for the diagnosis of pneumococcal pneumonia in pediatric patients with clinical and radiological evidence of bacterial infection. Bacterial DNA was extracted from sera by boiling and used without further purification in the PCR for the pneumolysin gene. None toxic reagents were used and the necessary steps to obtain the DNA were left at a minimum; furthermore, it overcomes the use of expensive commercial kits for DNA purification. The total procedure can be completed the same day of sampling and, most important, it avoids the use of sophisticated technology. Both in vitro analytical specificity and sensitivity (10 CFU/ml) of the assay were similar to those previously reported. When clinical samples were tested, the rate of positivity was shown to be 83.3
and 71
in pediatric patients with positive (group a) and negative blood cultures (group b), respectively. In group a, DNA detection was successful in samples from children without treatment or with less than 48 h of antibiotic therapy. None amplification was obtained from sera patients with viral infection or in samples from healthy controls. The application of the strategy described in this paper substantially seems to improve the diagnostic process in a determinate group: blood culture-negative children with pneumonia.
ABSTRACT
En este trabajo se ha estudiado la estabilidad de algunos fitoextractos glicólicos de manzanilla (Matricaria camomilla); quina (Cinchona callizaya); barbana (Arctium lappa); menta (Mentha piperita) y ortiga (Urtica echinata) que se emplean comúnmente en productos cosméticos. La acción sobre la piel depende de la integridad del fitocomplejo y por lo tanto de su concentración. Fue necesario definir un periodo adecuado de mantenimiento de esta clase de productos para la elaboración de estos y controlar el tiempo se amalizó algunas muestras del fitoextracto en diferentes matrices cosméticas tales como soluciones acuosas, glicólicos y tensioactivas. Han sido preservados adecuadamente y controlados periódicamente mediante análisis espectrofotométrico de acuerdo a la absorbancia y la segunda derivada. El periodo de control se realizó durante doce meses. Los valores de estabilidad de los diferentes fitoextractos presentan mayor modificación en soluciones acuosas frente a aquellas en soluciones tensioactivas y glicólicas respectivamente.
Subject(s)
Cosmetic Techniques , Drug Stability , Plant Extracts , Spectrophotometers , SpectrophotometryABSTRACT
In this paper, we report a fast, simple, and reproducible staining protocol for nucleic acids in agarose gels with a sensitivity in the order of 10 pg/mm2. It took only three steps: fixation, incubation with silver ions, and development of the gels (total time 50 min). The resulting calibration curves (area vs ng of loaded DNA) after a densitometric scanning of agarose gels stained with this procedure were linear up to 50 ng of double-stranded DNA. We found this method suitable for routine laboratory use and especially appropriate for densitometric analysis due to homogeneous background development. Furthermore, it avoids the pretreatment and/or drying steps proposed by other authors for agarose gels.
Subject(s)
Electrophoresis, Agar Gel/methods , Nucleic Acids/chemistry , Silver Staining/methods , Bacteriophage lambda/genetics , DNA/chemistry , DNA/metabolism , Densitometry/methods , Deoxyribonuclease HindIII/genetics , Deoxyribonuclease HindIII/metabolism , Ethidium/chemistry , Fluorescent Dyes/chemistry , Sensitivity and SpecificityABSTRACT
In the present work we describe a procedure for the purification of human pregnancy zone protein (PZP) from pooled late pregnancy plasma by using hydrophobic interaction chromatography (HIC) on a phenyl-Sepharose column. The HIC step allowed the complete isolation of haptoglobins and the partial separation of human alpha 2-macroglobulin (alpha 2-M) from a protein fraction containing PZP previously obtained by a DEAE-Sephacel chromatography. Pure and native PZP, with a recovery of nearly 25% and biological activity of protease-binding, was obtained by two definitive final steps consisting of zinc-chelate and size-filtration chromatographies. Moreover, we further present an alternative procedure for the purification of alpha 2-M from the same pregnancy plasma, based on the differential elution of PZP and alpha 2-M from the HIC. This purification step gave rise to a highly purified product with a recovery of 10%. This differential elution could be explained by differences in surface hydrophobicity observed between both proteins. In addition, considering the different hydrophobic properties exhibited by native PZP and PZP-protease complexes, HIC on phenyl-Sepharose column could also be used for separating both conformational states of PZP.
Subject(s)
Chromatography, Agarose/methods , Pregnancy Proteins/isolation & purification , alpha-Macroglobulins/isolation & purification , Chelating Agents , Electrophoresis, Polyacrylamide Gel , Female , Humans , Pregnancy , Pregnancy Proteins/chemistry , Protein Conformation , Sepharose/analogs & derivatives , Zinc , alpha-Macroglobulins/chemistryABSTRACT
The primary interaction between purified Agaricus bisporus lectin (ABL) and human IgA subclasses was studied by ABL-affinity chromatography, dot blot assay and competitive enzyme-lectin assay, considering that ABL could be an alternative tool for detection of IgA1 O-glycans. Both secretory IgA subclasses bound to ABL-Sepharose and the IgA2 subclass (which contains only N-glycans) was recovered with a high degree of purity when NH4OH was used as eluent. ABL-Ig interaction was also observed by dot blot assays using ABL-peroxidase against monoclonal IgA1 k Pan, IgA2m(1)k Gir, IgA2m(2)k Bel, secretory IgA2 and normal IgG (also contains only N-glycans). When these immunoglobulins were enzymatically treated with peptide N-glycosidase F (N-glycan hydrolysis), the ABL-IgA2 and -IgG interaction did not occur while IgA1 maintained a high degree of interaction with ABL. Also, the ABL-IgA interaction was observed by competitive enzyme-lectin assay, and when IgA1 subclass was treated with endo-alpha-N-acetylgalactosaminidase for O-glycans hydrolysis, the reactivity with ABL was very low. We conclude that the complementary use of ABL and peptide N-glycosidase F could be a useful tool to assess the O-glycosylation state of human IgA1 subclass, which is of relevant importance in the effector functions of immunoglobulins.
Subject(s)
Immunoglobulin A, Secretory/chemistry , Immunoglobulin A/chemistry , Lectins , Polysaccharides/analysis , Chromatography, Affinity , Female , Hemagglutination Inhibition Tests , Humans , Immunodiffusion , Immunoglobulin A/classification , Immunoglobulin A/isolation & purification , Immunoglobulin A, Secretory/isolation & purification , Milk, Human/immunologyABSTRACT
The interaction between purified Agaricus bisporus lectin and several human proteins was studied using the Ouchterlony double diffusion and immunoelectrophoresis techniques. Only one precipitation line was observed with normal human serum, normal human colostrum, IgA1 myeloma serum, both serum monoclonal and secretory IgA1 and monoclonal IgD. No reaction was observed with monoclonal and secretory IgA2, IgG, IgM, alpha 2 macroglobulin or pregnancy-associated alpha 2 glycoprotein. These results were confirmed by hemagglutination inhibition assays when IgA1, IgA2 and IgD were tested. On the basis of this reactivity, ABL could be a useful tool for distinguishing and isolating human IgA subclasses.
Subject(s)
Immunoglobulin A/chemistry , Immunoglobulin Isotypes/chemistry , Lectins/chemistry , Humans , Immunodiffusion , Immunoelectrophoresis , In Vitro Techniques , Phytohemagglutinins/chemistryABSTRACT
In the present work, we studied the efficacy of three blocking agents (HSA, BSA and OVA) in the inhibition of non-specific binding to PVC plates. According to the inhibition data, 1% OVA was the most effective blocking agent. On the other hand, the presence of detergents in all of the blocking solutions drastically decreased the percent inhibition of the non-specific binding. Furthermore, the effect of ligand concentration on adsorption and the kinetics of ligand adsorption to PVC plates were also investigated. Ligand adsorption is a linear function of input up to a limit (around 8.70 ng/mm2) where saturation is reached. The rate of adsorption of pure human IgG to PVC plates was proportionally increased with the temperature, as shown by proportional rate constants almost 2 times faster at 37 degrees C than at 4 degrees C. These results have practical implications for investigators using PVC for immunoassays and should be taken into consideration when designing such assays.
