Correlacion entre potenciales evocados auditivos estado estable y la audiometria tonal clasica en las frecuencias de 2000 y 2004 hz en sujetos normoyentes

51 p.En el presente estudio se comparó la Audiometría Tonal Liminar (ATL) con el Potencial Evocado Auditivo estado estable (PEAee), con la finalidad de inferir umbrales audiométricos y determinar si es confiable mediante un análisis de correlación con la ATL. Para la realización del estudio se evaluaron 40 oídos pertenecientes a 20 sujetos de la Universidad de Talca obteniendo umbrales auditivos mediante ATL y PEAee a multifrecuencia de forma binaural. Para efectos de esta investigación se analizaron las frecuencias de 2000 y 4000 Hz. Los resultados obtenidos no indican correlación entre ambos métodos diagnósticos. Además los umbrales electrofisiológicos son levemente mayores a los umbrales conductuales. Esta diferencia de umbrales disminuye en la frecuencia de 4000 Hz. En conclusión esta investigación no muestra evidencia significativa que permita establecer el PEAee como la principal medida electrofisiológica de la valoración de la audición en adultos jóvenes. Se sugieren realizar nuevas investigaciones con una muestra superior al de este estudio considerando el tipo de hipoacusia y el rango etáreo

Enhanced skin carcinogenesis and lack of thymus hyperplasia in transgenic mice expressing human cyclin D1b (CCND1b)

Cyclin D1b is an alternative transcript of the cyclin D1 gene (CCND1) expressed in human tumors. Its abundance is regulated by a single base pair polymorphism at the exon 4/intron 4 boundary (nucleotide 870). Epidemiological studies have shown a correlation between the presence of the G870A allele (that favors the splicing for cyclin D1b) with increased risk and less favorable outcome in several forms of cancer. More recently, it has been shown that, unlike cyclin D1a, the alternative transcript D1b by itself has the capacity to transform fibroblasts in vitro. In order to study the oncogenic potential of cyclin D1b, we developed transgenic mice expressing human cyclin D1b under the control of the bovine K5 promoter (K5D1b mice). Seven founders were obtained and none of them presented any significant phenotype or developed spontaneous tumors. Interestingly, K5D1b mice do not develop the fatal thymic hyperplasia, which is characteristic of the cyclin D1a transgenic mice (K5D1a). Susceptibility to skin carcinogenesis was tested in K5D1b mice using two-stage carcinogenesis protocols. In two independent experiments, K5D1b mice developed higher papilloma multiplicity as compared with wild-type littermates. However, when K5D1b mice were crossed with cyclin D1KO mice, the expression of cyclin D1b was unable to rescue the carcinogenesis-resistant phenotype of the cyclin D1 KO mice. To further explore the role of cyclin D1b in mouse models of carcinogenesis we carried out in silico analysis and in vitro experiments to evaluate the existence of a mouse homologous of the human cyclin D1b transcript. We were unable to find any evidence of an alternatively spliced transcript in mouse Ccnd1. These results show that human cyclin D1b has different biological functions than cyclin D1a and confirm its oncogenic properties.Fil: Rojas, Paola Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. University of Texas; Estados UnidosFil: Benavides, Fernando. University of Texas; Estados UnidosFil: Blando, Jorge. University of Texas; Estados UnidosFil: Pérez, Carlos. University of Texas; Estados UnidosFil: Cardenas, Kim. University of Texas; Estados UnidosFil: Richie, Ellen. University of Texas; Estados UnidosFil: Knudsen, Erik S.. Thomas Jefferson University; Estados UnidosFil: Johnson, David G.. University of Texas; Estados UnidosFil: Senderowicz, Adrian M.. Department of Health and Human Services. Food and Drug Administration. Center for Drug Evaluation and Research; Estados UnidosFil: Rodriguez Puebla, Marcelo L.. University of North Carolina; Estados UnidosFil: Conti, Claudio. University of Texas; Estados Unido

Desarrollo de lista corta para la evaluación del desempeño en alimentación-deglución en niños entre 1 y 5 años de edad con parálisis cerebral

Tesis (Fonoaudiólogo)La alimentación dentro de nuestra sociedad cumple un rol importante, ya sea, dentro de la dinámica familiar así como en las relaciones sociales, ya que, la comida genera momentos de diálogo y encuentro, es por esta razón, que es fundamental buscar la integración y un manejo adecuado durante el proceso de alimentación. Sin embargo, los niños con parálisis cerebral presentan numerosas dificultades frente a este proceso, por lo tanto, lo principal es no aislar al menor durante estas situaciones, sino que se debe manejar el contexto de manera óptima donde sea placentero para el niño, el cuidador y su entorno y de esta forma mejorar su calidad de vida. La investigación expuesta a continuación tiene dos propósitos, el primero es contar con un instrumento que permita valorar el desempeño de alimentación - deglución en niños con Parálisis Cerebral entre 1 y 5 años y el segundo, es lograr crear perfiles cualitativos, basándose en la Clasificación Internacional del Funcionamiento y la Discapacidad (CIF), esta permite integrar los componentes de actividad y participación, los cuales son fundamentales para los terapeutas que se desenvuelve en el área de la rehabilitación, esperando que los niños con Parálisis Cerebral obtengan mayor funcionalidad e integración en la sociedad. Es necesario tener en cuenta que en este estudio, los menores no presentan autonomía durante el acto de alimentación y esto genera un grado de dependencia de un tercero, es por esto que el fonoaudiólogo cumple un rol importante en la rehabilitación de la alimentación- deglución, siendo necesario conocer los factores en función de la CIF que influyen durante la alimentación, para así encasillar el rendimiento del menor durante la alimentación y conocer sus fortalezas, potenciandolas al máximo y compensando las debilidades. Por lo tanto, el objetivo de esta tesis es diseñar una lista corta para la evaluación del desempeño en la alimentación en el rango etario mencionado anteriormente, para caracterizar el desempeño del evaluado y crear perfiles cualitativos que guíen la futura intervención. Además, de poder comparar cuantitativamente el desempeño según las siguientes variables: tipo de parálisis cerebral, vía de alimentación y consistencias de los alimentos. Sin embargo, debido al corto tiempo asignado para esta investigación, la tesis abordará el primer propósito que consiste en la creación del instrumento. Por lo tanto, la base de este estudio es dar a conocer los procedimientos y análisis de la creación de este. Por consiguiente, se deja abierta la posibilidad de continuar con esta investigación para finalizar el segundo propósito. Los dejamos invitados a revisar esta investigación, ya que como terapeutas es de vital importancia conocer anticipadamente el desarrollo de la evolución de la alimentación en los niños con distintos tipos de PC y así poder abordar la intervención de manera más integral

Quantum effects on the BKT phase transition of two-dimensional Josephson arrays

The phase diagram of two dimensional Josephson arrays is studied by means of the mapping to the quantum XY model. The quantum effects onto the thermodynamics of the system can be evaluated with quantitative accuracy by a semiclassical method, the {\em pure-quantum self-consistent harmonic approximation}, and those of dissipation can be included in the same framework by the Caldeira-Leggett model. Within this scheme, the critical temperature of the superconductor-to-insulator transition, which is a Berezinskii-Kosterlitz-Thouless one, can be calculated in an extremely easy way as a function of the quantum coupling and of the dissipation mechanism. Previous quantum Monte Carlo results for the same model appear to be rather inaccurate, while the comparison with experimental data leads to conclude that the commonly assumed model is not suitable to describe in detail the real system.Comment: 4 pages, 2 figures, to be published in Phys. Rev.

Direct flux and current vector control for induction motor drives using model predictive control theory

The study presents the direct flux and current vector control of an induction motor (IM) drive, which is a relatively newer and promising control strategy, through the use of model predictive control (MPC) techniques. The results highlight that the fast flux control nature of direct flux control strategy is further enhanced by MPC. Predictive control is applied in two of its variants, namely the finite control set and modulated MPC, and the advantages and limitations of the two are underlined. This work also highlights, through experimental results, the importance of prioritising the flux part of the cost function which is particularly significant in the case of an IM drive. The performance of the MPC-based approach is compared with the proportional-integral controller, which also prioritises the flux control loop, under various operating regions of the drive such as in the flux-weakening regime. Simulations show the performance expected with different control strategies which is then verified through experiments

Adaptive Individualized high-dose preoperAtive (AIDA) chemoradiation in high-risk rectal cancer: a phase II trial

Purpose To evaluate the pathological complete response (pCR) rate of locally advanced rectal cancer (LARC) after adaptive high-dose neoadjuvant chemoradiation (CRT) based on (18) F-fluorodeoxyglucose positron emission tomography/computed tomography ((18) F-FDG-PET/CT).Methods The primary endpoint was the pCR rate. Secondary endpoints were the predictive value of (18) F-FDG-PET/CT on pathological response and acute and late toxicity. All patients performed (18) F-FDG-PET/CT at baseline (PET0) and after 2 weeks during CRT (PET1). The metabolic PET parameters were calculated both at the PET0 and PET1. The total CRT dose was 45 Gy to the pelvic lymph nodes and 50 Gy to the primary tumor, corresponding mesorectum, and to metastatic lymph nodes. Furthermore, a sequential boost was delivered to a biological target volume defined by PET1 with an additional dose of 5 Gy in 2 fractions. Capecitabine (825 mg/m(2) twice daily orally) was prescribed for the entire treatment duration.Results Eighteen patients (13 males, 5 females; median age 55 years [range, 41-77 years]) were enrolled in the trial. Patients underwent surgical resection at 8-9 weeks after the end of neoadjuvant CRT. No patient showed grade > 1 acute radiation-induced toxicity. Seven patients (38.8%) had TRG = 0 (complete regression), 5 (27.0%) showed TRG = 2, and 6 (33.0%) had TRG = 3. Based on the TRG results, patients were classified in two groups: TRG = 0 (pCR) and TRG = 1, 2, 3 (non pCR). Accepting p < 0.05 as the level of significance, at the Kruskal-Wallis test, the medians of baseline-MTV, interim-SUVmax, interim-SUVmean, interim-MTV, interim-TLG, and the MTV reduction were significantly different between the two groups. (18) F-FDG-PET/CT was able to predict the pCR in 77.8% of cases through compared evaluation of both baseline PET/CT and interim PET/CT.Conclusions Our results showed that a dose escalation on a reduced target in the final phase of CRT is well tolerated and able to provide a high pCR rate

Colistin Resistance in Carbapenem-Resistant Klebsiella pneumoniae: Laboratory Detection and Impact on Mortality

Background: Polymyxins including colistin are an important "last-line" treatment for infections caused by carbapenem-resistant Klebsiella pneumoniae (CRKp). Increasing use of colistin has led to resistance to this cationic antimicrobial peptide. Methods: A cohort nested within the Consortium on Resistance against Carbapenems in Klebsiella pneumoniae (CRACKLE) was constructed of patients with infection, or colonization with CRKp isolates tested for colistin susceptibility during the study period of December, 2011 to October, 2014. Reference colistin resistance determination as performed by broth macrodilution was compared to results from clinical microbiology laboratories (Etest) and to polymyxin resistance testing. Each patient was included once, at the time of their first colistin-tested CRKp positive culture. Time to 30-day in-hospital all-cause mortality was evaluated by Kaplan-Meier curves and Cox proportional hazard modeling. Results: In 246 patients with CRKp, 13% possessed ColR CRKp. ColR was underestimated by Etest (very major error rate = 35%, major error rate = 0.4%). A variety of rep-PCR strain types were encountered in both the ColS and the ColR groups. Carbapenem resistance was mediated primarily by blaKPC-2 (46%) and blaKPC-3 (50%). ColR was associated with increased hazard for in-hospital mortality (aHR 3.48; 95% confidence interval, 1.73-6.57; P < .001). The plasmid-associated ColR genes, mcr-1 and mcr-2 were not detected in any of the ColR CRKp. Conclusions: In this cohort, 13% of patients with CRKp presented with ColR CRKp. The apparent polyclonal nature of the isolates suggests de novo emergence of ColR in this cohort as the primary factor driving ColR. Importantly, mortality was increased in patients with ColR isolates

Genomic heterogeneity underlies multidrug resistance in Pseudomonas aeruginosa: A population-level analysis beyond susceptibility testing.

BACKGROUND: Pseudomonas aeruginosa is a persistent and difficult-to-treat pathogen in many patients, especially those with Cystic Fibrosis (CF). Herein, we describe a longitudinal analysis of a series of multidrug resistant (MDR) P. aeruginosa isolates recovered in a 17-month period, from a young female CF patient who underwent double lung transplantation. Our goal was to understand the genetic basis of the observed resistance phenotypes, establish the genomic population diversity, and define the nature of sequence evolution over time. METHODS: Twenty-two sequential P. aeruginosa isolates were obtained within a 17-month period, before and after a double-lung transplant. At the end of the study period, antimicrobial susceptibility testing, whole genome sequencing (WGS), phylogenetic analyses and RNAseq were performed in order to understand the genetic basis of the observed resistance phenotypes, establish the genomic population diversity, and define the nature of sequence changes over time. RESULTS: The majority of isolates were resistant to almost all tested antibiotics. A phylogenetic reconstruction revealed 3 major clades representing a genotypically and phenotypically heterogeneous population. The pattern of mutation accumulation and variation of gene expression suggested that a group of closely related strains was present in the patient prior to transplantation and continued to change throughout the course of treatment. A trend toward accumulation of mutations over time was observed. Different mutations in the DNA mismatch repair gene mutL consistent with a hypermutator phenotype were observed in two clades. RNAseq performed on 12 representative isolates revealed substantial differences in the expression of genes associated with antibiotic resistance and virulence traits. CONCLUSIONS: The overwhelming current practice in the clinical laboratories setting relies on obtaining a pure culture and reporting the antibiogram from a few isolated colonies to inform therapy decisions. Our analyses revealed significant underlying genomic heterogeneity and unpredictable evolutionary patterns that were independent of prior antibiotic treatment, highlighting the need for comprehensive sampling and population-level analysis when gathering microbiological data in the context of CF P. aeruginosa chronic infection. Our findings challenge the applicability of antimicrobial stewardship programs based on single-isolate resistance profiles for the selection of antibiotic regimens in chronic infections such as CF

Anomalous coarsening driven by reversible charge transfer at metal–organic interfaces

The unique electronic properties and functional tunability of polycyclic aromatic hydrocarbons have recently fostered high hopes for their use in flexible, green, portable, and cheap technologies. Most applications require the deposition of thin molecular films onto conductive electrodes. The growth of the first few molecular layers represents a crucial step in the device fabrication since it determines the structure of the molecular film and the energy level alignment of the metal–organic interface. Here, we explore the formation of this interface by analyzing the interplay between reversible molecule–substrate charge transfer, yielding intermolecular repulsion, and van der Waals attractions in driving the molecular assembly. Using a series of ad hoc designed molecules to balance the two effects, we combine scanning tunnelling microscopy with atomistic simulations to study the self-assembly behavior. Our systematic analysis identifies a growth mode characterized by anomalous coarsening that we anticipate to occur in a wide class of metal–organic interfaces and which should thus be considered as integral part of the self-assembly process when depositing a molecule on a conducting surface