RESUMEN
BACKGROUND: Postoperative pulmonary complications (PPC) are the most frequent postoperative complications, with an estimated prevalence in elective surgery ranging from 20% in observational cohort studies to 40% in randomized clinical trials. However, the prevalence of PPCs in patients undergoing emergency abdominal surgery is not well defined. Lung-protective ventilation aims to minimize ventilator-induced lung injury and reduce PPCs. The open lung approach (OLA), which combines recruitment manoeuvres (RM) and positive end-expiratory pressure (PEEP) titration, aims to minimize areas of atelectasis and the development of PPCs; however, there is no conclusive evidence in the literature that OLA can prevent PPCs. The purpose of this study is to compare an individualized perioperative OLA with conventional standardized lung-protective ventilation in patients undergoing emergency abdominal surgery with clinical signs of intraoperative lung collapse. METHODS: Randomized international clinical trial to compare an individualized perioperative OLA (RM plus individualized PEEP and individualized postoperative respiratory support) with conventional lung-protective ventilation (standard PEEP of 5 cmH2O and conventional postoperative oxygen therapy) in patients undergoing emergency abdominal surgery with clinical signs of lung collapse. Patients will be randomised to open-label parallel groups. The primary outcome is any severe PPC during the first 7 postoperative days, including: acute respiratory failure, pneumothorax, weaning failure, acute respiratory distress syndrome, and pulmonary infection. The estimated sample size is 732 patients (366 per group). The final sample size will be readjusted during the interim analysis. DISCUSSION: The Individualized Perioperative Open-lung Ventilatory Strategy in emergency abdominal laparotomy (iPROVE-EAL) is the first multicentre, randomized, controlled trial to investigate whether an individualized perioperative approach prevents PPCs in patients undergoing emergency surgery.
Asunto(s)
Abdomen , Laparotomía , Respiración con Presión Positiva , Complicaciones Posoperatorias , Humanos , Estudios Prospectivos , Abdomen/cirugía , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/epidemiología , Respiración con Presión Positiva/métodos , Urgencias Médicas , Ensayos Clínicos Controlados Aleatorios como Asunto , Atención Perioperativa/métodos , Respiración Artificial/métodosRESUMEN
PURPOSE: The occurrence of adverse events (AE) in hospitalized patients substancially increases the risk of disability or death, having a major negative clinical and economic impact on public health. For early identification of patients at risk and to establish preventive measures, different healthcare systems have implemented rapid response systems (RRS). The aim of this study was to carry out a cost-effectiveness analysis of implementing a RRS in a tertiary-care hospital. METHODS: We included all the patients admitted to Hospital Clínic de Barcelona from 1 to 2016 to 31 December 2016. The cost-effectiveness analysis was summarized as the incremental cost-effectiveness ratio (incremental cost divided by the incremental effectiveness of the two alternatives, RRS versus non-RRS). The effectiveness of the RRS, defined as improvements in health outcomes (AE, cardiopulmonary arrest and mortality), was obtained from the literature and applied to the included patient cohort. A budget impact analysis on the implementation of the RRS from a hospital perspective was performed over a 5-year time horizon. RESULTS: 42,409 patients were included, and 448 (1.05%) had severe AE requiring ICU admission. The cost-effectiveness analysis showed an incremental cost (savings) of EUR - 1,471,101 of RRS versus the non-RRS. The budgetary impact showed a cost reduction of EUR 896,762.00 in the first year and EUR 1,588,579.00 from the second to the fifth year. CONCLUSIONS: The present analysis shows the RRS as a dominant, less costly and more effective structure compared to the non-RRS.
Asunto(s)
Paro Cardíaco , Análisis Costo-Beneficio , Hospitalización , Humanos , Centros de Atención TerciariaRESUMEN
INTRODUCTION: Household cleaning products and cosmetics are necessary for daily life and widely used by the population. However, their use may not be risk-free, especially when they are not used or stored as recommended. It is important to characterize exposures, as this is useful for developing stra tegies to reduce morbidity, mortality, and health costs associated, especially in the child population. OBJECTIVE: To describe reports associated with household cleaning products and cosmetics exposure in patients under the age of 12, reported to the Poison Information Center of the Catholic University of Chile (CITUC). PATIENTS AND METHOD: Descriptive cross-sectional study of phone calls to CITUC during 2016. The analyzed variables were age, sex, product, caller, caller and incident location, ex posure circumstances, exposure route(s), symptoms, and severity from manual records and from the WHO's electronic record software 'INTOX Data Management System'. RESULTS: 3,415 cases met the inclusion criteria. Children under the age of five represented 91% of the exposures, and 58.5% were male. 99.4% were accidental exposures, and 98.6% occurred at home. Family members (57%) and health personnel (42%) made the calls. 68.3% of the patients had no symptoms after exposure. The four products with the highest incidence were household bleach (27.6%), floor cleaners and polishers (13.1%), dish soap (7.9%), and perfume/cologne (5.8%). The main exposure route was by ingestion (89.4%). CONCLUSIONS: Household cleaning products and cosmetics are common causes of exposures especially in children under the age of five. Although these products have a low morbidity and mortality rate, it is important to educate the population to prevent possible poisonings in the child population.
Asunto(s)
Cosméticos/envenenamiento , Productos Domésticos/envenenamiento , Centros de Control de Intoxicaciones/estadística & datos numéricos , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , MasculinoRESUMEN
Some bacterial peptidyl-prolyl cis/trans isomerases (PPIases) are involved in secretory protein folding after the translocation step. Streptomyces lividans has been used as a host for engineering extracellular overproduction of homologous and heterologous proteins in industrial applications. Although the mechanisms governing the major secretory pathway (Sec route) and the minor secretory pathway (Tat route) are reasonably well described, the function of proteins responsible for the extracellular secretory protein folding is not characterized as yet. We have characterized a Tat-dependent S. lividans FK506-binding protein-like lipoprotein (FKBP) that has PPIase activity. A mutant in the sli-fkbp gene induces a secretion stress response and affects secretion and activity of the Sec-dependent protein α-amylase. Additionally, propagation in high copy number of the sli-fkbp gene has a positive effect on the activity of both the overproduced α-amylase and the overproduced Tat-dependent agarase, both containing proline cis isomers. Targeted proteomic analyses showed that a relevant group of secreted proteins in S. lividans TK21 are affected by Sli-FKBP, revealing a wide substrate range. The results obtained indicate that, regardless of the secretory route used by proteins in S. lividans, adjusting the expression of sli-fkbp may facilitate folding of dependent proteins when engineering Streptomyces strains for the overproduction of homologous or heterologous secretory proteins.
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Proteínas Bacterianas/metabolismo , Pliegue de Proteína , Streptomyces lividans/enzimología , Proteínas de Unión a Tacrolimus/metabolismo , Proteínas Bacterianas/genética , Glicósido Hidrolasas/metabolismo , Streptomyces lividans/genética , Proteínas de Unión a Tacrolimus/genética , alfa-Amilasas/metabolismoRESUMEN
INTRODUCCIÓN: Los productos de aseo y cosméticos son necesarios en el diario vivir y ampliamente utilizados por la población. Sin embargo, su uso puede no estar exento de riesgos, especialmente cuando no se utilizan o almacenan según lo recomendado. Es importante caracterizar las exposiciones, ya que eso es útil para implementar estrategias para reducir la morbilidad, mortalidad y costos asociados, especialmente en la población infantil. OBJETIVO: Caracterizar los reportes asociados a exposiciones a productos de aseo y productos cosméticos en pacientes menores de 12 años reportados al Centro de Información Toxicológica de la Universidad Católica de Chile (CITUC). PACIENTES Y MÉTODO: Estudio descriptivo transversal de llamados telefónicos reportados a CITUC durante el año 2016. Se analizaron las variables: edad, sexo, agente, interlocutor, localización del interlocutor e inciden te, circunstancia de exposición, vía(s) de exposición, sintomatología, y severidad, mediante fichas de registro manual y desde el software de registro electrónico denominado "INTOX Data Manage ment System" de la OMS. RESULTADOS: Cumplieron criterios de inclusión 3.415 casos. Los menores de 5 años representaron el 91% de las exposiciones y el 58,5% correspondió al sexo masculino. Un 99,4% correspondió a exposiciones accidentales y el 98,6% ocurrieron en el hogar. El 68,3% no presentó síntomas, tras la exposición. Las llamadas fueron realizadas por familiares (57%) y personal de salud (42%). Los 4 agentes con mayor incidencia fueron cloro doméstico (27,6%), limpiadores y lustres de pisos (13,1%), lavalozas (7,9%) y perfumes/colonias (5,8%). La principal vía de exposición fue digestiva (89,4%). CONCLUSIONES: Los productos de aseo y cosméticos son causas comunes de exposiciones especialmente en menores de 5 años. Si bien son productos de baja mortalidad y morbilidad, es importante educar a la población para prevenir posibles intoxicaciones en la población infantil.
INTRODUCTION: Household cleaning products and cosmetics are necessary for daily life and widely used by the population. However, their use may not be risk-free, especially when they are not used or stored as recommended. It is important to characterize exposures, as this is useful for developing stra tegies to reduce morbidity, mortality, and health costs associated, especially in the child population. OBJECTIVE: To describe reports associated with household cleaning products and cosmetics exposure in patients under the age of 12, reported to the Poison Information Center of the Catholic University of Chile (CITUC). PATIENTS AND METHOD: Descriptive cross-sectional study of phone calls to CITUC during 2016. The analyzed variables were age, sex, product, caller, caller and incident location, ex posure circumstances, exposure route(s), symptoms, and severity from manual records and from the WHO's electronic record software 'INTOX Data Management System'. RESULTS: 3,415 cases met the inclusion criteria. Children under the age of five represented 91% of the exposures, and 58.5% were male. 99.4% were accidental exposures, and 98.6% occurred at home. Family members (57%) and health personnel (42%) made the calls. 68.3% of the patients had no symptoms after exposure. The four products with the highest incidence were household bleach (27.6%), floor cleaners and polishers (13.1%), dish soap (7.9%), and perfume/cologne (5.8%). The main exposure route was by ingestion (89.4%). CONCLUSIONS: Household cleaning products and cosmetics are common causes of exposures especially in children under the age of five. Although these products have a low morbidity and mortality rate, it is important to educate the population to prevent possible poisonings in the child population.
Asunto(s)
Humanos , Masculino , Femenino , Recién Nacido , Lactante , Preescolar , Niño , Centros de Control de Intoxicaciones/estadística & datos numéricos , Cosméticos/envenenamiento , Productos Domésticos/envenenamiento , Incidencia , Estudios TransversalesRESUMEN
El secuestro pulmonar es una malformación congénita poco frecuente, generalmente asintomática hasta que la lesión se infecta, debutando entonces como infecciones respiratorias de repetición. El diagnóstico se confirma mediante pruebas de imagen que permitan objetivar el tejido pulmonar no funcionante irrigado por circulación sistémica. El tratamiento de elección es la resección quirúrgica con ligadura de los vasos nutricios
Pulmonary sequestration is a rare congenital abnormality. Most of them are asymptomatic but they can appear as recurrent respiratory infections. Radiological tests bring to light a non functioning mass of lung that receives its arterial blood supply from the systemic circulation. Treatment is made with a surgical resection by bonding the vascular supply
Asunto(s)
Humanos , Masculino , Adulto , Secuestro Broncopulmonar/complicaciones , Infecciones del Sistema Respiratorio/complicaciones , Anomalías del Sistema Respiratorio/diagnóstico por imagen , Secuestro Broncopulmonar/cirugía , Neumonectomía , Cirugía Torácica Asistida por VideoRESUMEN
La dilatación aneurismática de la arteria pulmonar es una patología rara y clínicamente inespecífica, por lo que el diagnóstico se basa en pruebas de imagen, como la TC o la angiorresonancia. Puede ser idiopática (menos frecuente) cuando la etiología es indeterminada o secundaria a diversas patologías, muchas de ellas identificables con técnicas de imagen complementarias, como el ecocardiograma. Debido a que la mayoría de los pacientes se diagnostican como hallazgo casual, están asintomáticos o estables, o tienen bajo riesgo de rotura, son muy pocos los que precisan de tratamiento quirúrgico
Aneurysm dilation of pulmonary artery is a very rare disease and the clinic is non-specific. Final diagnosis relies on imaging tests as computed tomography and nuclear magnetic resonance. They can be idiopathic (less frequent, when an indeterminate etiology occurs) or secondary to several pathologies, most of which can be identified with other imaging tests like echocardiogram. As in most patients the disease is a casual finding, are asymptomatic or with haemodynamic stability or have a low risk of rupture, only a few need surgery
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Humanos , Masculino , Femenino , Persona de Mediana Edad , Aneurisma de la Aorta Torácica/diagnóstico , Embolia Pulmonar/diagnóstico , Hipertensión Pulmonar/diagnóstico , Ecocardiografía , Tomografía Computarizada por Rayos XRESUMEN
INTRODUCTION: The relationship between persistent postoperative cognitive decline and the more common acute variety remains unknown; using data acquired in preclinical studies of postoperative cognitive decline we attempted to characterize this relationship. METHODS: Low capacity runner (LCR) rats, which have all the features of the metabolic syndrome, were compared postoperatively with high capacity runner (HCR) rats for memory, assessed by trace fear conditioning (TFC) on the 7th postoperative day, and learning and memory (probe trial [PT]) assessed by the Morris water-maze (MWM) at 3 months postoperatively. Rate of learning (AL) data from the MWM test, were estimated by non-linear mixed effects modeling. The individual rat's TFC result at postoperative day (POD) 7 was correlated with its AL and PT from the MWM data sets at postoperative day POD 90. RESULTS: A single exponential decay model best described AL in the MWM with LCR and surgery (LCR-SURG) being the only significant covariates; first order AL rate constant was 0.07 s(-1) in LCR-SURG and 0.16s(-1) in the remaining groups (p<0.05). TFC was significantly correlated with both AL (R=0.74; p<0.0001) and PT (R=0.49; p<0.01). CONCLUSION: Severity of memory decline at 1 week after surgery presaged long-lasting deteriorations in learning and memory.
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Trastornos del Conocimiento/metabolismo , Enfermedades Metabólicas/complicaciones , Complicaciones Posoperatorias/metabolismo , Complicaciones Posoperatorias/psicología , Animales , Trastornos del Conocimiento/etiología , Condicionamiento Clásico/fisiología , Miedo/fisiología , Miembro Posterior/lesiones , Miembro Posterior/cirugía , Aprendizaje por Laberinto/fisiología , Memoria/fisiología , Ratas , Factores de TiempoRESUMEN
No disponible
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Humanos , Masculino , Anciano de 80 o más Años , Válvula Mitral , Ventrículos Cardíacos , Obstrucción del Flujo Ventricular Externo/tratamiento farmacológico , Obstrucción del Flujo Ventricular Externo/rehabilitación , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Volumen Sistólico , Sístole , Norepinefrina/uso terapéutico , Fluidoterapia/métodos , Vasoconstrictores/uso terapéuticoAsunto(s)
Complicaciones Intraoperatorias/etiología , Válvula Mitral/fisiopatología , Choque/etiología , Obstrucción del Flujo Ventricular Externo/etiología , Anciano de 80 o más Años , Terapia Combinada , Dobutamina/uso terapéutico , Fluidoterapia , Hemorreología , Humanos , Complicaciones Intraoperatorias/fisiopatología , Complicaciones Intraoperatorias/terapia , Masculino , Monitoreo Intraoperatorio/instrumentación , Norepinefrina/uso terapéutico , Choque/tratamiento farmacológico , Choque/fisiopatología , Neoplasias Gástricas/cirugía , Sístole , Vasoconstrictores/uso terapéutico , Obstrucción del Flujo Ventricular Externo/fisiopatologíaRESUMEN
INTRODUCTION: Low-molecular-weight heparins are commonly used for the prophylaxis of thromboembolic disease. In contrast to therapeutic doses, recommended prophylactic doses are fixed (i.e., 40 mg/day enoxaparin). Dosing of patients with extreme body weights has not been well studied, especially dosing of low weight patients. OBJECTIVES: To establish the anti-Xa activity that results from 40 mg/day enoxaparin in inpatients with body weight ≤ 55 kg. PATIENTS/METHODS: Cross-sectional study including inpatients older than 18 years, with body weight ≤ 55 kg, and whose treating physician found indication for 40 mg/day enoxaparin. We excluded patients with renal failure and those using oral anticoagulants. Anti-Xa activity was measured 3 hours after the second dose of enoxaparin. Statistical analyses were conducted to determine the effect of body weight on anti-Xa levels. RESULTS: Average age was 72.5 years (interquartile range, 30) and median body weight was 49.7 kg (interquartile range, 7). Twenty-five percent of patients weighed ≤ 45 kg, 37.5% weighed 46-50 kg, and 37.5% weighed 51-55 kg. The mean anti-Xa activity was 0.54±0.18IU/ml, and 60% of the patients exhibited activity ≥0.5 IU/ml. Weight and anti-Xa activity inversely correlated (Spearman's rho=-0.428, p=0.001). Patients weighing ≤ 45 kg exhibited higher anti-Xa activity (0.61±0.18 IU/ml, p=0.008) than heavier patients and an odds ratio of 8 for anti-Xa level ≥0.5IU/ml (95% CI: 1.42-45.06). CONCLUSIONS: Anti-factor Xa activity rises significantly when body weight decreases. Patients of low weight, especially those weighing <45 kg, exhibited an anti-Xa activity higher than the desired range for thromboembolic prophylaxis.
Asunto(s)
Anticoagulantes/uso terapéutico , Peso Corporal/efectos de los fármacos , Enoxaparina/uso terapéutico , Factor Xa/metabolismo , Tromboembolia Venosa/prevención & control , Anciano , Estudios Transversales , Femenino , Hospitalización , Humanos , Masculino , Estudios Prospectivos , Tromboembolia Venosa/sangre , Tromboembolia Venosa/tratamiento farmacológicoRESUMEN
Type I signal peptidases are responsible for the proteolytic cleavage of the signal peptide of secreted proteins. In the gram-positive bacterium Streptomyces lividans, four adjacent genes (sipW, sipX, sipY and sipZ) were isolated encoding putative type I signal peptidases. In this work, the different sip genes were cloned and expressed. Subsequently, the Sip proteins were purified to raise antibodies. Although the four Sip proteins share a low degree of sequence similarity and differ significantly in size and pI, anti-Sip antibodies cross-reacted intensively. Functional signal peptidase processing activity for each of these Sip proteins was shown both in vitro and in vivo. The different Sip proteins did not exhibit the same cleavage efficiency on the Bacillus subtilis pre-chitosanase.
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Proteínas Bacterianas/metabolismo , Proteínas de la Membrana , Precursores de Proteínas/metabolismo , Serina Endopeptidasas/genética , Serina Endopeptidasas/metabolismo , Streptomyces/enzimología , Anticuerpos Antibacterianos/inmunología , Western Blotting , Fraccionamiento Celular , Clonación Molecular , Reacciones Cruzadas , Serina Endopeptidasas/inmunología , Streptomyces/genética , Fracciones Subcelulares/metabolismoRESUMEN
Most bacterial membranes contain one or two type I signal peptidases (SPases) for the removal of signal peptides from export proteins. For Streptomyces lividans, four different type I SPases (denoted SipW, SipX, SipY, and SipZ) were previously described. In this communication, we report the experimental determination of the membrane topology of these SPases. A protease protection assay of SPase tendamistat fusions confirmed the presence of the N- as well as the C-terminal transmembrane anchor for SipY. SipX and SipZ have a predicted topology similar to that of SipY. These three S. lividans SPases are currently the only known prokaryotic-type type I SPases of gram-positive bacteria with a C-terminal transmembrane anchor, thereby establishing a new subclass of type I SPases. In contrast, S. lividans SipW contains only the N-terminal transmembrane segment, similar to most type I SPases of gram-positive bacteria. Functional analysis showed that the C-terminal transmembrane anchor of SipY is important to enhance the processing activity, both in vitro as well as in vivo. Moreover, for the S. lividans SPases, a relation seems to exist between the presence or absence of the C-terminal anchor and the relative contributions to the total SPase processing activity in the cell. SipY and SipZ, two SPases with a C-terminal anchor, were shown to be of major importance to the cell. Accordingly, for SipW, missing the C-terminal anchor, a minor role in preprotein processing was found.
Asunto(s)
Serina Endopeptidasas/química , Serina Endopeptidasas/metabolismo , Streptomyces/enzimología , Secuencia de Bases , Membrana Celular/enzimología , Cartilla de ADN , Bacterias Grampositivas/enzimología , Cinética , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Plásmidos , Conformación Proteica , Estructura Secundaria de Proteína , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Serina Endopeptidasas/genética , Streptomyces/genéticaRESUMEN
Direct percutaneous exposure is the main route of HCV transmission. In Puerto Rico half of people infected with HIV use illicit drugs. The effects of HCV in the course of HIV infection and vice versa have been extensively studied, but remain highly controversial. This may be due to HCV genetic heterogeneity. Therefore, a complex classification into genotypes has emerged that prompted us to determined how this impacts a population of intravenous drug users (IDUs) co-infected with HIV-1. Using Inno-LiPa II technique, we analyzed samples from 171 HCV-HIV-1-co-infected IDUs and 375 from a general HCV population of unknown HIV or source of infection status. Similar HCV genotype distribution was detected in these populations. HCV genotype 1a was the most frequently in IDUs-co-infected with HIV-1, followed by 1b and 3a. Twenty mixed infections and 5 undetermined genotypes were reported. A reduced HCV viral load was observed in HIV-1 positives with wasting syndrome. Individuals with a high HIV-1 viral load presented a low HCV viral load. There were no correlation between HCV genotypes and AIDS-related event. Patients with genotype 1b showed a higher HCV viral load. Males presented higher HCV viral load than females. Females were predominantly affected by genotype 1a, and men by 1a and 1b. Neither the HCV viral load nor the frequency of genotypes were influenced by the antiretroviral modality. The importance of continuous genotype monitoring is stressed.
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Infecciones por VIH/complicaciones , Hepacivirus/genética , Hepatitis C/virología , Abuso de Sustancias por Vía Intravenosa/complicaciones , Adulto , Recuento de Linfocito CD4 , Estudios Transversales , Femenino , Frecuencia de los Genes , Genotipo , Infecciones por VIH/virología , VIH-1 , Hepacivirus/aislamiento & purificación , Hepatitis C/complicaciones , Hepatitis C/inmunología , Humanos , Masculino , Puerto Rico , ARN Viral/sangre , Carga ViralRESUMEN
Her-2/neu belongs to the family of tyrosine kinase transmembrane proteins whose overexpression has been associated with a poor prognosis in patients with breast cancer. The product of this proto-oncogene is overexpressed in 25-30% of human breast cancer and is the target of selective immunotherapy. Concerned about the ethnic differences on the expression of this oncogene, we have evaluated 143 consecutive specimens of primary breast cancer diagnosed in San Pablo Hospital, Puerto Rico. The specimens were analyzed for Her-2/neu expression using immunohistochemistry assays (Hercept test). We have related the expression of hormone receptor status, percent cells in S phase, DNA ploidy, tumor size, nodal status and menopausal state with the Her2/neu expression. Out of 143 specimens, 28 overexpressed the Her-2/neu (19.6%). Of the Her/2 negative 30/114 (26%) were estrogen receptor negative as compared to 9/27 (33%) (p = 0.464). The degree of aneuploidy was abnormal in 25/104 (24%) in the Her-2/neu negative vs 11/27 (41%) p = 0.083. The percent cell in DNA synthesis was high in 16/77 (21%) in Her-2/neu negative vs 4/15 (27%) p = 0.613. The tumor size was greater than 2 cm in 35/106 (33%) in Her-2/neu negative vs 9/23 (39%) p = 0.575. In the progesterone specimens negative for Her2, 44/114 (39%) were Her2/neu negative vs 15/27 (56%) p = 0.108. No differences were seen regarding menopausal status, age and nuclear grading. A trend favoring abnormal aneuploidy in Her2/neu positive was seen. Nodal involvement was significantly associated with Her2/neu overexpression. (p = 0.037). Although the incidence of Her2 overexpression found in this database was somewhat lower than the one reported in the literature, this might also be due to the small cohort examined or to the technique utilized.
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Adenocarcinoma/metabolismo , Neoplasias de la Mama/metabolismo , Proteínas Oncogénicas/metabolismo , Receptor ErbB-2/metabolismo , Adenocarcinoma/etnología , Adenocarcinoma/genética , Adenocarcinoma/patología , Adulto , Factores de Edad , Anciano , Biomarcadores de Tumor/análisis , Neoplasias de la Mama/etnología , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Estudios de Cohortes , Femenino , Hispánicos o Latinos , Humanos , Inmunohistoquímica , Metástasis Linfática , Menopausia , Persona de Mediana Edad , Proteínas Oncogénicas/inmunología , Ploidias , Proto-Oncogenes Mas , Puerto Rico/etnología , Receptor ErbB-2/inmunología , Fase SRESUMEN
The regulatory region and the region coding for the signal peptide of an extracellular agarase have been used to synthesize and secrete the heterologous Escherichia coli TEM beta-lactamase in Streptomyces lividans. The transcriptional regulation of the chimeric gene, and the secretion pattern of the chimeric gene product, coincided with those of the agarase gene. The negative glucose effect on the secretion of the protein was reverted when the recombinant bacterium was grown in the chemostat under phosphate limiting conditions.
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Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica , Streptomyces/enzimología , Streptomyces/genética , beta-Lactamasas/biosíntesis , Medios de Cultivo , Genes Bacterianos , Glicósido Hidrolasas/genética , Glicósido Hidrolasas/metabolismo , Señales de Clasificación de Proteína/genética , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/metabolismo , Mapeo Restrictivo/métodos , Endonucleasas Específicas del ADN y ARN con un Solo Filamento/metabolismo , Streptomyces/crecimiento & desarrollo , Transcripción Genética , beta-Lactamasas/genética , beta-Lactamasas/metabolismoRESUMEN
Contaminated soils from an oil refinery were screened for the presence of microorganisms capable of accumulating either nickel, vanadium, or both metals. Three strains of bacteria that belonged to the family Enterobacteriaceae were selected. Two of them were Escherichia hermannii strains, and outer membrane profile (OMP) analysis showed that they were similar to a strain of clinical origin; the other one was an Enterobacter cloacae strain that differed from clinical isolates. The selected bacteria accumulated both nickel and vanadium. Growth in the presence of vanadium induced multidrug resistance phenotypes in E. hermannii and E. cloacae. Incubation with this metal changed the OMP profile of E. hermannii but did not produce variations in the expression of the major OMPs of E. cloacae.
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Resistencia a Múltiples Medicamentos , Enterobacter cloacae/fisiología , Escherichia/fisiología , Níquel/metabolismo , Microbiología del Suelo , Vanadio/metabolismo , Vanadio/farmacología , Antibacterianos/farmacología , Proteínas de la Membrana Bacteriana Externa/biosíntesis , Proteínas de la Membrana Bacteriana Externa/aislamiento & purificación , Farmacorresistencia Microbiana , Enterobacter cloacae/efectos de los fármacos , Enterobacter cloacae/aislamiento & purificación , Escherichia/efectos de los fármacos , Escherichia/aislamiento & purificación , Aceites Combustibles , Pruebas de Sensibilidad MicrobianaRESUMEN
Using synthetic oligonucleotides derived from known signal peptidase genes and a multicopy plasmid as a vector, a signal peptidase gene (sipZ) from Streptomyces lividansTK21 has been cloned. The primary structure of the gene has been determined and the amino acid composition of the SipZ protein inferred. SipZ is 258 aa long and showed homology to other type I signal peptidases, containing like them an N-terminal transmembrane anchor. Alignment of SipZ with other known SPases allowed the identification of a conserved sequence of amino acids specific for Gram-positive bacteria.
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Genes Bacterianos , Proteínas de la Membrana , Serina Endopeptidasas/genética , Streptomyces/enzimología , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Secuencia Conservada , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa/métodos , Mapeo Restrictivo , Alineación de Secuencia , Análisis de Secuencia de ADN , Serina Endopeptidasas/química , Streptomyces/genéticaRESUMEN
The agarase gene from Streptomyces coelicolor has been cloned in the non-producer bacterium Streptomyces lividans under the control of its own set of promoters and under the control of a heterologous promoter that is functional only during exponential growth. The best level of overproduction was obtained when the strain containing the natural gene was cultivated in fed batch with mannitol as carbon source. The protein, with a relative molecular mass of 32 kDa, has been purified following an affinity purification method. Contaminating activities seem to be absent from the purified enzyme preparation that can be used to purify DNA from agarose gels.