Asunto(s)
Proteínas Bacterianas/metabolismo , Desinfectantes/farmacología , Desinfección/métodos , Microbiología Ambiental , Bacterias Gramnegativas/enzimología , Habitaciones de Pacientes , Guías de Práctica Clínica como Asunto , beta-Lactamasas/metabolismo , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/aislamiento & purificación , HumanosRESUMEN
Amplification and overexpression of erbB2/neu proto-oncogene is observed in 20-30% human breast cancer and is inversely correlated with the survival of the patient. Despite this, somatic activating mutations within erbB2 in human breast cancers are rare. However, we have previously reported that a splice isoform of erbB2, containing an in-frame deletion of exon 16 (herein referred to as ErbB2ΔEx16), results in oncogenic activation of erbB2 because of constitutive dimerization of the ErbB2 receptor. Here, we demonstrate that the ErbB2ΔEx16 is a major oncogenic driver in breast cancer that constitutively signals from the cell surface. We further show that inducible expression of the ErbB2ΔEx16 variant in mammary gland of transgenic mice results in the rapid development of metastatic multifocal mammary tumors. Genetic and biochemical characterization of the ErbB2ΔEx16-derived mammary tumors exhibit several unique features that distinguish this model from the conventional ErbB2 ones expressing the erbB2 proto-oncogene in mammary epithelium. Unlike the wild-type ErbB2-derived tumors that express luminal keratins, ErbB2ΔEx16-derived tumors exhibit high degree of intratumoral heterogeneity co-expressing both basal and luminal keratins. Consistent with these distinct pathological features, the ErbB2ΔEx16 tumors exhibit distinct signaling and gene expression profiles that correlate with activation of number of key transcription factors implicated in breast cancer metastasis and cancer stem cell renewal.
Asunto(s)
Empalme Alternativo , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Transformación Celular Neoplásica/genética , Receptor ErbB-2/genética , Microambiente Tumoral/genética , Animales , Línea Celular Tumoral , Análisis por Conglomerados , Modelos Animales de Enfermedad , Exones , Matriz Extracelular/metabolismo , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Neoplasias Pulmonares/secundario , Ratones , Ratones Transgénicos , Metástasis de la Neoplasia , Fenotipo , Proto-Oncogenes Mas , Eliminación de Secuencia , Factores de Transcripción/metabolismoAsunto(s)
Proteínas Bacterianas/metabolismo , Infección Hospitalaria/prevención & control , Descontaminación/métodos , Transmisión de Enfermedad Infecciosa/prevención & control , Desinfección/métodos , Bacterias Gramnegativas/enzimología , Infecciones por Bacterias Gramnegativas/prevención & control , beta-Lactamasas/metabolismo , Bacterias Gramnegativas/aislamiento & purificación , Infecciones por Bacterias Gramnegativas/microbiología , HumanosAsunto(s)
Farmacorresistencia Bacteriana Múltiple , Bacterias Gramnegativas/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/epidemiología , Infecciones por Bacterias Gramnegativas/microbiología , Control de Infecciones/métodos , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Transmisión de Enfermedad Infecciosa/prevención & control , Salud Global , Bacterias Gramnegativas/aislamiento & purificación , HumanosRESUMEN
The myc oncogene is overexpressed in almost half of all breast and ovarian cancers, but attempts at therapeutic interventions against myc have proven to be challenging. Myc regulates multiple biological processes, including the cell cycle, and as such is associated with cell proliferation and tumor progression. We identified a protein signature of high myc, low p27 and high phospho-Rb significantly correlated with poor patient survival in breast and ovarian cancers. Screening of a miRNA library by functional proteomics in multiple cell lines and integration of data from patient tumors revealed a panel of five microRNAs (miRNAs) (miR-124, miR-365, miR-34b*, miR-18a and miR-506) as potential tumor suppressors capable of reversing the p27/myc/phospho-Rb protein signature. Mechanistic studies revealed an RNA-activation function of miR-124 resulting in direct induction of p27 protein levels by binding to and inducing transcription on the p27 promoter region leading to a subsequent G1 arrest. Additionally, in vivo studies utilizing a xenograft model demonstrated that nanoparticle-mediated delivery of miR-124 could reduce tumor growth and sensitize cells to etoposide, suggesting a clinical application of miRNAs as therapeutics to target the functional effect of myc on tumor growth.
Asunto(s)
Neoplasias de la Mama/genética , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Regulación Neoplásica de la Expresión Génica , Genes myc , MicroARNs/fisiología , Neoplasias Ováricas/genética , Proteína de Retinoblastoma/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Femenino , Humanos , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/patología , Fosfoproteínas/metabolismo , Proteómica/métodos , Proteína de Retinoblastoma/metabolismo , Transcriptoma , Células Tumorales CultivadasAsunto(s)
Infección Hospitalaria/epidemiología , Infección Hospitalaria/prevención & control , Control de Infecciones/métodos , Infecciones Bacterianas/epidemiología , Infecciones Bacterianas/prevención & control , Infecciones Bacterianas/transmisión , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/transmisión , Infección Hospitalaria/transmisión , Farmacorresistencia Bacteriana Múltiple , Bacterias Gramnegativas/efectos de los fármacos , Humanos , Medio Oriente , Sociedades CientíficasRESUMEN
Caveolin-1 (Cav1) is an integral membrane, scaffolding protein found in plasma membrane invaginations (caveolae). Cav1 regulates multiple cancer-associated processes. In breast cancer, a tumor suppressive role for Cav1 has been suggested; however, Cav1 is frequently overexpressed in aggressive breast cancer subtypes, suggesting an oncogenic function in advanced-stage disease. To further delineate Cav1 function in breast cancer progression, we evaluated its expression levels among a panel of cell lines representing a spectrum of breast cancer phenotypes. In basal-like (the most aggressive BC subtype) breast cancer cells, Cav1 was consistently upregulated, and positively correlated with increased cell proliferation, anchorage-independent growth, and migration and invasion. To identify mechanisms of Cav1 gene regulation, we compared DNA methylation levels within promoter 'CpG islands' (CGIs) with 'CGI shores', recently described regions that flank CGIs with less CG-density. Integration of genome-wide DNA methylation profiles ('methylomes') with Cav1 expression in 30 breast cancer cell lines showed that differential methylation of CGI shores, but not CGIs, significantly regulated Cav1 expression. In breast cancer cell lines having low Cav1 expression (despite promoter CGI hypomethylation), we found that treatment with a DNA methyltransferase inhibitor induced Cav1 expression via CGI shore demethylation. In addition, further methylome assessments revealed that breast cancer aggressiveness associated with Cav1 CGI shore methylation levels, with shore hypermethylation in minimally aggressive, luminal breast cancer cells and shore hypomethylation in highly aggressive, basal-like cells. Cav1 CGI shore methylation was also observed in human breast tumors, and overall survival rates of breast cancer patients lacking estrogen receptor α (ERα) negatively correlated with Cav1 expression. Based on this first study of Cav1 (a potential oncogene) CGI shore methylation, we suggest this phenomenon may represent a new prognostic marker for ERα-negative, basal-like breast cancer.
Asunto(s)
Neoplasias de la Mama/genética , Caveolina 1/genética , Islas de CpG , Metilación de ADN , Regulación Neoplásica de la Expresión Génica , Azacitidina/farmacología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Caveolina 1/metabolismo , Línea Celular Tumoral , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Proteínas Oncogénicas/genética , Proteínas Oncogénicas/metabolismo , Regiones Promotoras GenéticasRESUMEN
There are few data on meticillin-resistant Staphylococcus aureus (MRSA) screening in obstetrics, a largely healthy population that should be at lower risk for MRSA than most hospitalized populations. From January 2009 to December 2011 nose swabs were screened from 5548 of 21,770 (25.5%) women who delivered at Birmingham Women's Hospital. Only 29 (0.5%) were MRSA positive: MRSA infections occurred later in three cases. MRSA infections occurred in a further 13 mother-infant pairs, including six cases where mothers were MRSA screen negative. Seventeen mothers had risk factors for MRSA. MRSA is not widespread in obstetrics, and large-scale screening of nasal swabs is of limited value in preventing MRSA-related morbidity in this population.
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Portador Sano/epidemiología , Portador Sano/microbiología , Tamizaje Masivo/métodos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Femenino , Humanos , Recién Nacido , Nariz/microbiología , Servicio de Ginecología y Obstetricia en Hospital , Embarazo , Prevalencia , Factores de RiesgoRESUMEN
Point-of-care testing (POCT) is one of the fastest growing sectors of laboratory diagnostics. Most tests in routine use are haematology or biochemistry tests that are of low complexity. Microbiology POCT has been constrained by a lack of tests that are both accurate and of low complexity. We describe our experience of the practical issues around using more complex POCT for detection of Group B streptococci (GBS) in swabs from labouring women. We evaluated two tests for their feasibility in POCT: an optical immune assay (Biostar OIA Strep B, Inverness Medical, Princetown, NJ) and a PCR (IDI-Strep B, Cepheid, Sunnyvale, CA), which have been categorised as being of moderate and high complexity, respectively. A total of 12 unqualified midwifery assistants (MA) were trained to undertake testing on the delivery suite. A systematic approach to the introduction and management of POC testing was used. Modelling showed that the probability of test results being available within a clinically useful timescale was high. However, in the clinical setting, we found it impossible to maintain reliable availability of trained testers. Implementation of more complex POC testing is technically feasible, but it is expensive, and may be difficult to achieve in a busy delivery suite.
Asunto(s)
Trabajo de Parto , Sistemas de Atención de Punto , Streptococcus agalactiae/aislamiento & purificación , Parto Obstétrico , Femenino , Humanos , Embarazo , Recto/microbiología , Sensibilidad y Especificidad , Infecciones Estreptocócicas/diagnóstico , Infecciones Estreptocócicas/microbiología , Vagina/microbiologíaRESUMEN
Deletion of 11q23-q24 is frequent in a diverse variety of malignancies, including breast and colorectal carcinoma, implicating the presence of a tumor suppressor gene at that chromosomal region. We examined a 6-Mb region on 11q23 by high-resolution deletion mapping, using both loss of heterozygosity analysis and customized microarray comparative genomic hybridization. LARG (leukemia-associated Rho guanine-nucleotide exchange factor) (also called ARHGEF12), identified from the analysed region, is frequently underexpressed in breast and colorectal carcinomas with a reduced expression observed in all breast cancer cell lines (n=11), in 12 of 38 (32%) primary breast cancers, 5 of 10 (50%) colorectal cell lines and in 20 of 37 (54%) primary colorectal cancers. Underexpression of the LARG transcript was significantly associated with genomic loss (P=0.00334). Hypermethylation of the LARG promoter was not detected in either breast or colorectal cancer, and treatment of four breast and four colorectal cancer cell lines with 5-aza-2'-deoxycytidine and/or trichostatin A did not result in a reactivation of LARG. Enforced expression of LARG in breast and colorectal cancer cells by stable transfection resulted in reduced cell proliferation and colony formation, as well as in a markedly slower cell migration rate in colorectal cancer cells, providing functional evidence for LARG as a candidate tumor suppressor gene.
Asunto(s)
Neoplasias de la Mama/metabolismo , Cromosomas Humanos Par 11/metabolismo , Neoplasias Colorrectales/metabolismo , Factores de Intercambio de Guanina Nucleótido/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Antimetabolitos Antineoplásicos/farmacología , Azacitidina/análogos & derivados , Azacitidina/farmacología , Neoplasias de la Mama/genética , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Proliferación Celular/efectos de los fármacos , Deleción Cromosómica , Mapeo Cromosómico , Cromosomas Humanos Par 11/genética , Neoplasias Colorrectales/genética , Metilación de ADN/efectos de los fármacos , Metilación de ADN/genética , Decitabina , Femenino , Factores de Intercambio de Guanina Nucleótido/genética , Humanos , Ácidos Hidroxámicos/farmacología , Masculino , Hibridación de Ácido Nucleico , Regiones Promotoras Genéticas/genética , Inhibidores de la Síntesis de la Proteína , Factores de Intercambio de Guanina Nucleótido Rho , Transfección , Proteínas Supresoras de Tumor/genéticaAsunto(s)
Enfermedades Transmisibles/epidemiología , Infección Hospitalaria/epidemiología , Antiinfecciosos/uso terapéutico , Niño , Preescolar , Enfermedades Transmisibles/tratamiento farmacológico , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/microbiología , Utilización de Medicamentos , Encuestas Epidemiológicas , Hospitales Pediátricos , Humanos , Prevalencia , Sepsis/epidemiología , Reino Unido/epidemiologíaRESUMEN
Meticillin-resistant Staphylococcus aureus (MRSA) isolates from children presenting to Birmingham hospitals were characterized using molecular methods. The study was performed on MRSA isolates from children aged =16 years, identified between March 2004 and December 2004, from three hospitals offering general paediatric services. Fifty isolates were classified as either community-acquired (CA-MRSA) or hospital-acquired MRSA (HA-MRSA) according to Centers for Disease Control and Prevention (CDC) criteria. They underwent susceptibility testing and pulsed-field gel electrophoresis (PFGE) analyses. Polymerase chain reaction (PCR) methodology was used to determine the type of staphylococcal chromosome cassette (SCCmec) and the presence or absence of genes encoding Panton-Valentine leucocidin (PVL). Overall, 31 (62%) MRSA were defined as CA-MRSA. PFGE band pattern and SCCmec analysis were similar to EMRSA 15 for 72% of isolates. Over 80% of isolates contained SCCmec type IV; one isolate was untypable. Genes encoding PVL were not detected. MRSA in children presenting to Birmingham hospitals classified as CA-MRSA are most likely to resemble the usual hospital epidemic strains. None of the isolates fulfilled the criteria for de-novo CA-MRSA based on PFGE, PVL production and SCCmec analysis.
Asunto(s)
Proteínas Bacterianas/metabolismo , Resistencia a la Meticilina/efectos de los fármacos , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/efectos de los fármacos , Adolescente , Proteínas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Técnicas de Tipificación Bacteriana/métodos , Niño , Preescolar , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Infecciones Comunitarias Adquiridas/epidemiología , Inglaterra/epidemiología , Exotoxinas/metabolismo , Hospitales/estadística & datos numéricos , Humanos , Lactante , Leucocidinas/metabolismo , Resistencia a la Meticilina/fisiología , Pruebas de Sensibilidad Microbiana/métodos , Proteínas de Unión a las Penicilinas , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/genéticaRESUMEN
BACKGROUND: Representational oligonucleotide microarray analysis has been developed for detection of single nucleotide polymorphisms and/or for genome copy number changes. In this process, the intensity of hybridization to oligonucleotides arrays is increased by hybridizing a polymerase chain reaction (PCR)-amplified representation of reduced genomic complexity. However, hybridization to some oligonucleotides is not sufficiently high to allow precise analysis of that portion of the genome. METHODS: In an effort to identify aspects of oligonucleotide hybridization affecting signal intensity, we explored the importance of the PCR product strand to which each oligonucleotide is homologous and the sequence of the array oligonucleotides. We accomplished this by hybridizing multiple PCR-amplified products to oligonucleotide arrays carrying two sense and two antisense 50-mer oligonucleotides for each PCR amplicon. RESULTS: In some cases, hybridization intensity depended more strongly on the PCR amplicon strand (i.e., sense vs. antisense) than on the detection oligonucleotide sequence. In other cases, the oligonucleotide sequence seemed to dominate. CONCLUSION: Oligonucleotide arrays for analysis of DNA copy number or for single nucleotide polymorphism content should be designed to carry probes to sense and antisense strands of each PCR amplicon to ensure sufficient hybridization and signal intensity.
Asunto(s)
Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Aneuploidia , Cromosomas Humanos Par 20/genética , Cromosomas Humanos X/genética , Femenino , Dosificación de Gen , Humanos , Hibridación de Ácido Nucleico , Sondas de Oligonucleótidos , Reacción en Cadena de la PolimerasaRESUMEN
AIMS: To investigate the epidemiological and clinical aspects of MRSA among inpatients and outpatients presenting to hospital. METHODS: Analysis of demographic, epidemiological, and clinical data collected on 385 children first identified as having MRSA between January 1998 and December 2003 in a 250 bed English children's hospital. RESULTS: There were 267 inpatients and 118 outpatients. The number of new cases of MRSA declined from 72 in 1998 to 52 in 2003, whereas hospital activity increased. Ninety nine (37.1%) inpatients acquired MRSA outside the hospital; a further 90 occurred among 31 clusters of cases. One hundred and seventy eight (66.7%) inpatients were aged <2 years; cardiac services and paediatric & neonatal surgery accounted for 59.6% of cases. Dermatology and A&E accounted for 51.7% of outpatients; 73.8% of outpatients had recently previously attended the hospital. A total of 13.9% of inpatients with MRSA developed bacteraemia; MRSA accounted for 15% of Staphylococcus aureus bacteraemias. The risk of MRSA bacteraemia in colonised patients, and the proportion of S aureus bacteraemias that were MRSA, varied between specialties. Intravascular devices were the most common source of MRSA bacteraemia (63.4% of cases). The mortality rate was 7.3%. CONCLUSIONS: Enhanced surveillance of MRSA can identify at-risk patient groups, thus facilitating targeting of control measures. The absence of a link between numbers of cases of acquisition of MRSA and bacteraemia suggests that the rise in MRSA bacteraemia may not solely reflect an increase in MRSA prevalence in children in the UK. The need for larger epidemiological studies is emphasised.
Asunto(s)
Infección Hospitalaria/epidemiología , Resistencia a la Meticilina , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/efectos de los fármacos , Distribución por Edad , Bacteriemia/epidemiología , Bacteriemia/microbiología , Niño , Preescolar , Infección Hospitalaria/microbiología , Inglaterra/epidemiología , Femenino , Hospitalización , Hospitales Pediátricos , Hospitales de Enseñanza , Humanos , Lactante , Recién Nacido , Masculino , Medicina/estadística & datos numéricos , Servicio Ambulatorio en Hospital , Especialización , Infecciones Estafilocócicas/microbiologíaRESUMEN
Chickenpox is generally a benign childhood disease. Bacterial superinfection is the commonest complication, and can be severe and life-threatening. We describe a 15-year-old boy with disseminated Staphylococcus aureus infection following chickenpox.
Asunto(s)
Varicela/complicaciones , Infecciones Estafilocócicas/diagnóstico , Staphylococcus aureus/aislamiento & purificación , Adolescente , Antibacterianos/uso terapéutico , Humanos , Masculino , Penicilina G/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/etiología , Factores de Tiempo , Resultado del TratamientoRESUMEN
We have assembled arrays of approximately 2,400 BAC clones for measurement of DNA copy number across the human genome. The arrays provide precise measurement (s.d. of log2 ratios=0.05-0.10) in cell lines and clinical material, so that we can reliably detect and quantify high-level amplifications and single-copy alterations in diploid, polyploid and heterogeneous backgrounds.