Solution processed nanostructured hybrid materials based on PbS quantum dots and reduced graphene oxide with tunable optoelectronic properties.

Nanostructured hybrid materials (NHMs) are promising candidates to improve the performance of several materials in different applications. In the case of optoelectronic technologies, the ability to tune the optical absorption of such NHMs is an appealing feature. Along with the capacity to transform the absorbed light into charge carriers (CC), and their consequently efficient transport to the different electrodes. In this regard, NHM based on graphene-like structures and semiconductor QDs are appealing candidates, assuming the NHMs retain the light absorption and CC photogeneration properties of semiconductor QDs, and the excellent CC transport properties displayed by graphene-like materials. In the current work a solution-processed NHM using PbS quantum dots (QDs) and graphene oxide (GO) was fabricated in a layer-by-layer configuration by dip-coating. Afterwards, these NHMs were reduced by thermal or chemical methods. Reduction process had a direct impact on the final optoelectronic properties displayed by the NHMs. All reduced samples displayed a decrement in their resistivity, particularly the sample chemically reduced, displaying a 107 fold decrease; mainly attributed to N-doping in the reduced graphene oxide (rGO). The optical absorption coefficients also showed a dependence on the rGO's reduction degree, with reduced samples displaying higher values, and sample thermally reduced at 300 °C showing the highest absorption coefficient, due to the combined absorption of unaltered PbS QDs and the appearance of sp2 regions within rGO. The photogenerated current increased in most reduced samples, displaying the highest photocurrent the sample reduced at 400 °C, presenting a 2500-fold increment compared to the NHM before reduction, attributed to an enhanced CC transfer from PbS QDs to rGO, as a consequence of an improved band alignment between them. These results show clear evidence on how the optoelectronic properties of NHMs based on semiconductor nanoparticles and rGO, can be tuned based on their configuration and the reduction process parameters.

Nutritional and non-nutritional agents that stimulate white adipose tissue browning.

Obesity is a public health problem present in both developed and developing countries. The white adipose tissue (WAT) is the main deposit of lipids when there is an excess of energy. Its pathological growth is directly linked to the development of obesity and to a wide number of comorbidities, such as insulin-resistance, cardiovascular disease, among others. In this scenario, it becomes imperative to develop new approaches to the treatment and prevention of obesity and its comorbidities. It has been documented that the browning of WAT could be a suitable strategy to tackle the obesity epidemic that is developing worldwide. Currently there is an intense search for bioactive compounds with anti-obesity properties, which present the particular ability to generate thermogenesis in the brown adipose tissue (BAT) or beige. The present study provide recent information of the bioactive nutritional compounds capable of inducing thermogenesis and therefore capable of generate positive effects on health.

Evaluation of concordance among three cardiac output measurement techniques in adult patients during cardiovascular surgery postoperative care.

INTRODUCTION: The standard method for cardiac output measuring is thermodilution although it is an invasive technique. Transesophageal Echocardiography (TEE) offers a dynamic and functional alternative to thermodilution. OBJECTIVE: Analyze concordance between two TEE methods and thermodilution for cardiac output assessment. METHODS: Observational concordance study in cardiovascular surgery patients that required pulmonary artery catheter. TEE cardiac output measurement at both mitral annulus (MA) and left ventricle outflow tract (LVOT) were performed. Results were compared with thermodilution. Correlation was evaluated by Lin's concordance correlation coefficient and Bland-Altman analysis. Statistical analysis was undertaken in STATA 13.0. RESULTS: Twenty-five patients were enrolled. Fifty two percent of patients were male, median age and ejection fraction was 63 years and 35% respectively. Median thermodilution, LVOT and MA -measured cardiac output was 3.25 L/min, 3.46 L/min and 8.4 L/min respectively. Different values between thermodilution and MA measurements were found (Lin concordance=0.071; Confidence Interval 95%=-0.009 to 0.151; Spearman's correlation=0.22) as values between thermodilution and LVOT (Lin concordance=0.232; Confidence Interval 95%=-0.12 a 0.537; Spearman's correlation 0.28). Bland-Altman analysis showed greater difference between MA measurements and thermodilution (DM=-0.408; Bland-Altman Limits=-0.809 to -0.007), than the other echocardiographic findings (DM=0.007; Bland-Altman Limits=-0.441 to 0.428). CONCLUSION: Results from cardiac output measurement by doppler and 2D-TEE on both MA and LVOT do not correlate with those obtained by thermodilution.

A re-evaluation of the peak P-T conditions of eclogite-facies metamorphism of the Paleozoic Acatlán Complex (Mexico) reveals deeper subduction.

Eclogites in the Acatlán Complex, southern Mexico, record the subduction history of the complex. Previous studies indicate that the proto-Acatlán Complex reached < 50 km depth during subduction. Yet, a recent study reported higher pressures for a single eclogite, questioning the maximum depth reached by the complex during subduction. In this work, I re-calculate eclogite pressure and temperature (P-T) conditions using thermobarometric methods applicable to eclogite-facies mafic rocks to a set of eclogites cropping out throughout the high-pressure belt of the Acatlán Complex-the Piaxtla Suite. I find that Acatlán eclogites record substantially-and systematically-greater pressures than previously reported. Calculations show that eclogites from the central part of the Piaxtla Suite (in the Piaxtla area) record consistent pressures of ~ 2.0 GPa and temperatures ranging between 460 and 675 °C. Eclogites from the northern part of the Piaxtla Suite (Mimilulco and Santa Cruz Organal areas) lack phengite, thus pressures were not calculated; temperatures calculated for these rocks at a fixed pressure (2.0 GPa) yield contrasting temperatures (511 °C and 870 °C, respectively). Mimilulco eclogite likely records similar pressures (~ 2.0 GPa) to other Piaxtla eclogites, whereas the pressures of Santa Cruz Organal eclogites might have been different, and likely experiencing a different thermal history compared to the rest of the eclogites from the Piaxtla Suite. Overall, these results indicate that the Acatlán Complex subducted to greater depths than previously thought implying a faster burial-exhumation cycle of the proto-Acatlán Complex.

Barium selenate supplementation and its effect on intramammary infection in pasture-based dairy cows.

A significant proportion of cattle receive inadequate dietary Se because of its low content in soils and pastures of various regions of the world. Several economically important diseases in dairy cows, such as mastitis, have been associated with Se deficiency. The objective of this study was to evaluate the effect of a single injection of a long-acting form of Se at drying off on the risk and incidence rate of new intramammary infections and on milk somatic cell count in the subsequent lactation in pasture-based dairy cows. Forty-nine Chilean Holstein-Friesian cows were fed a diet containing <0.05 mg of Se/kg of ration dry matter. During the dry period, cows were allocated to 1 of 2 groups, a supplemented (n=24) group treated with a single subcutaneous injection of barium selenate 2 mo before calving and a control group (n=25) that remained unsupplemented. Duplicate foremilk samples were aseptically collected within 6 d after calving and every 2 wk until drying-off for bacteriological culture. Milk samples were also collected monthly for somatic cell count evaluation. Blood samples were collected before treatment and at 30, 90, 180, and 270 d after treatment for analysis of blood glutathione peroxidase (GPx) activity. The activity of glutathione peroxidase was higher in supplemented cows 30 d after the injection until the end of the study. The risk and incidence rate of new intramammary infections was not affected by supplementation. A progressive increase in somatic cell count was observed throughout lactation, but there was no effect of supplementation. In conclusion, a one-time injection of barium selenate 2 mo before calving in these pasture-based dairy cows did not affect udder health in the subsequent lactation, indicating that Se basal intake was adequate for preventing subclinical mastitis in pasture-based cows in southern Chile.

Quantitative telomerase expression in glioblastomas shows regional variation and down-regulation with therapy but no correlation with patient outcome.

Despite the nearly ubiquitous expression of telomerase in almost all types of malignant human tumors, studies have shown widely varying positivity in the highest-grade glioma, the glioblastomas (GBMs), ranging from 26% to 100% of tumors analyzed. We have previously shown significant variability in positive versus negative telomerase expression from region to region within the same GBM. In this study, we hypothesized that application of new quantitative methodology would extend our previous observations and identify whether there is heterogeneity in levels of protein expression even within areas positive for telomerase in high-grade gliomas. Finally, we sought to correlate quantitative telomerase expression with patient outcome and therapeutic response. Quantitative analysis was achieved by polymerase chain-based TRAP assay with phosphorimager analysis and compared with clinical information obtained from 19 patients, most with primary, untreated GBMs. Results showed up to 3-fold variability in telomerase levels across multiple regional samples from the same patient, as well as between patients. In 5 of 6 patients with recurrent tumors who had received intervening radiation therapy or chemotherapy, telomerase was downregulated in the second, post-therapy sample. These data provide in vivo corroboration of recent in vitro experiments showing telomerase downregulation after radiation therapy or chemotherapy treatment of cell lines. Our finding of variability in levels of telomerase expression in GBMs parallels the known heterogeneity of these tumors for histologic features and cell growth-related factors. Statistical analysis showed no relationship between TRAP score and either time to clinical progression or time to death.

Immunohistochemical localization of telomerase hTERT protein and analysis of clonality in multifocal vulvar intraepithelial neoplasia.

Vulvar intraepithelial neoplasias (VINs) are potentially premalignant lesions of the squamous mucosa. The immunohistochemical distribution of the catalytic protein subunit of telomerase (hTERT) and the patterns of X chromosome inactivation were investigated as markers of neoplasia in samples from a patient with multifocal and diffuse VIN. hTERT nuclear staining in VIN correlated with squamous maturation and the degree of nuclear atypia. Normal mucosa revealed faint nuclear staining of parabasal cells and lower intermediate layer squamous cells. Monoclonal composition was demonstrated in 0 of 3 samples of VIN1, 2 of 3 samples of VIN2, and 13 of 13 samples of VIN3. The patterns of X chromosome inactivation indicated intramucosal extension and multifocal origin of individual lesions. Five samples of histologically normal vulvar squamous epithelium revealed a random pattern of X chromosome inactivation, consistent with polyclonal composition. All 19 samples from 9 lesions contained human papillomavirus (HPV)-16 sequences. Neither mutations in the p53 tumor suppressor gene or K-ras oncogenes nor loss of heterozygosity at 7 chromosomal loci were detected in any of the 19 samples of VIN. These results demonstrate that HPV-associated VIN may result from multifocal and diffuse 2-dimensional intraepithelial expansion of an immortalized monoclonal cell population.

Quantitative renal scintigraphic determination of the glomerular filtration rate in cats with normal and abnormal kidney function, using 99mTc-diethylenetriaminepentaacetic acid.

The nuclear imaging technique known as quantitative renal scintigraphy was validated as a means to assess the kidney function of cats. Renal function tests were performed in 6 healthy cats and 3 cats with clinical manifestations of kidney failure. In addition, the nephrotoxic drugs, gentamicin sulfate, or amphotericin B were used in an attempt to induce renal failure in 4 cats. Using linear regression analysis, equations were derived to estimate the glomerular filtration rate (GFR) on the basis of the renal percent uptake of 99mTc-diethylenetriaminepentaacetic acid (99mTc-DTPA). One-way ANOVA and Student's t test were used to evaluate treatment effects on clearances of inulin and creatinine, percent uptake of 99mTc-DTPA, and serum creatinine concentrations. The results show that the percent uptake of 99mTc-DTPA by the kidneys correlated well with the GFR obtained through the clearance of inulin. Thus, it was concluded that quantitative renal scintigraphy, using 99mTc-DTPA as a marker of kidney function, is an adequate technique to estimate the kidney function of healthy cats and cats with functional renal impairment. The best estimate of the GFR of cats, using the percentage dose of 99mTc-DTPA, was obtained on the 1- to 3-minute postinjection interval of the marker, using data that was background-subtracted, but not corrected for tissue absorption of gamma rays or binding of 99mTc-DTPA to plasma proteins. There was no significant difference in the mean inulin clearance, creatinine clearance, or percent uptake of 99mTc-DTPA between the 3 treatment groups of this study.(ABSTRACT TRUNCATED AT 250 WORDS)

Nanodomain induced anomalous magnetic and electronic transport properties of LaBaCo2O5.5+δ highly epitaxial thin films.

A giant magnetoresistance effect (∼46% at 20 K under 7 T) and anomalous magnetic properties were found in a highly epitaxial double perovskite LaBaCo2O5.5+δ (LBCO) thin film on (001) MgO. Aberration-corrected Electron Microscopy and related analytical techniques were employed to understand the nature of these unusual physical properties. The as-grown film is epitaxial with the c-axis of the LBCO structure lying in the film plane and with an interface relationship given by (100)LBCO || (001)MgO and [001]LBCO || [100]MgO or [010]MgO. Orderly oxygen vacancies were observed by line profile electron energy loss spectroscopy and by atomic resolution imaging. Especially, oxygen vacancy and nanodomain structures were found to have a crucial effect on the electronic transport and magnetic properties.

Caracterización físico-química y actividad antimicrobiana de la secreción mucosa de Achatina fulica / Mother-infant bonding disorders: prevalence, risk factors, diagnostic criteria and assessment strategies

Introducción: El caracol gigante africano Achatina fulica es reconocido como una plaga que afecta la biodiversidad, la Salud Pública y la productividad. Sin embargo, se ha demostrado que su secreción mucosa tiene propiedades cosméticas, cicatrizantes y antimicrobianas. Objetivo: Determinar las características físico-químicas y evaluar la actividad antimicrobiana de la secreción mucosa de Achatina fulica. Metodología: Se hicieron pruebas bioquímicas para la determinación cualitativa y cuantitativa de glúcidos, proteínas y lípidos. Se determinó el contenido de Calcio, Potasio, cloruros, Sodio y Magnesio. Se midieron los parámetros de conductividad eléctrica, potencial óxido-reducción, saturación de oxígeno, oxígeno total disuelto, pH, sólidos disueltos totales. Se realizó un ensayo de actividad antibacteriana por la técnica de microdilución en caldo. Resultados: Se encontraron glúcidos en concentraciones de 582 μg/mL en la fracción soluble y de 62.1 μg/mL en la fracción de mucinas, y proteínas en concentraciones de 836 μg/mL en la fracción soluble y de 1413 μg/mL en la fracción de mucinas. Se observó actividad antimicrobiana frente a las tres cepas ensayadas. Streptococcus agalactiae alcanzó un MIC90 a una concentración de 3,6 mg/mL con la fracción de mucinas; Staphylococcus aureus resistente a meticilina tuvo un MIC50 de 3,3 mg/mL y Escherichia coli un MIC 70 de 3.8 mg/mL. Conclusiones: Se reportan por primera vez las características físicas y los oligoelementos presente en la secreción de Achatina fulica. La actividad antibacteriana obtenida frente a cepas Gram positivas y Gram negativas plantea la necesidad de realizar estudios para purificar las moléculas con dicha actividad, conocer los mecanismos de acción y establecer la inocuidad, entre otros.

Introduction: The giant African snail Achatina fulica is recognized as a scourge affecting biodiversity, public health and productivity. However, it has been shown that the mucus has cosmetic, healing and antimicrobial properties. Objective: Determine physico-chemical characteristics and evaluate the antimicrobial activity of the mucus. Methodology: Qualitative and quantitative determinations of carbohydrates, proteins and lipids were made by biochemical tests. Using multiparameter meter parameters of electrical conductivity, redox potential, oxygen saturation, the total dissolved oxygen, pH, total dissolved solids were measured. Content of Calcium, Potassium, chloride, Sodium and Magnesium was determined. Antibacterial activity assay was performed by broth microdilution method against Gram positive and Gram negative bacteria. Results: Carbohydrates were found in concentrations of 582 μg/mL in soluble fraction and 62.1 μg/mL in mucin fraction, and protein concentration of 836 μg/mL in the soluble fraction and 1413 μg/mL in mucin fraction. Antimicrobial activity was demonstrated against the three strains tested. Streptococcus agalactiae reached MIC90 at a concentration of 3.6 μg/mL with mucin fraction; Methicillin-Resistant Staphylococcus aureus had a MIC50 of 3.3 mg / mL and Escherichia coli had a MIC70 of 3.8 mg / mL. Conclusions: This is the first report of the physical and trace elements in the secretion of Achatina fulica. The antibacterial activity obtained against Gram positive and Gram negative strains raises the need for studies to purify the molecules with such activity, understanding the mechanisms of action and establish the safety, among others.

CENTROS ESPECIALIZADOS DE SAN VICENTE FUNDACIÓN: HOSPITAL VERDE CON CERTIFICACIÓN LEED / SPECIALIZED CENTERS OF SAN VICENTE FUNDACIÓN: LEED-CERTIFIED GREEN HOSPITAL / CENTROS ESPECIALIZADOS DE SAN VICENTE FUNDAÇÃO: HOSPITAL VERDE COM CERTIFICAÇÃO LEED

Con el incremento de la conciencia mundial por el medio ambiente y el desarrollo de modelos de certificación y evaluación de edificaciones denominadas verdes, que apuntan a la auto-sostenibilidad, San Vicente Fundación, con la edificación de Centros Especializados, buscó ser, además de una edificación con automatización y control del consumo de energía, la primera edificación hospitalaria Verde de Colombia. De esta manera alcanzó la certificación LEED categoría plata. Dicha certificación, a la cual los proyectos se presentan voluntariamente, consiste en una medición del desempeño de la edificación en aspectos como el impacto ambiental, el consumo de recursos y la innovación. En este articulo se describen algunos aspectos de las tecnologías implementadas para desarrollar Centros Especializados como una hospital verde y a su vez, la obtención de la certificación LEED.

With increasing global awareness about the environment and the development of models of certification and evaluation of so-called green buildings, aimed at self-sustainability, San Vicente Fundación, with the construction of specialized centers, sought to be, along with a building automation and control with energy consumption, the first green hospital in Colombia. Thus it reached LEED silver category. This certification, where projects registered voluntarily, is a measure of the performance of the building in areas such as environmental impact, resource consumption, and innovation. This article describes some aspects of the technologies implemented to develop specialized centers as a green hospital and in turn, the LEED certification.

Com o aumento da consciência global sobre o meio ambiente e o desenvolvimento de modelos de certificação e de avaliação de prédios chamados verde, apontando para a auto sustentabilidade, San Vicente Fundação, com a construção de centros especializados, procurou ser, juntamente um prédio com automatização e controle do consumo de energia, o primeiro edifício verde da Colômbia. Assim, alcançou a categoria prata LEED. Esta certificação, que se apresentam os projetos forma voluntária, é uma medida do desempenho do edifício em áreas como o impacto ambiental, o consumo de recursos e inovação. Este artigo descreve alguns aspectos das tecnologias implementadas para desenvolver centros especializados como um hospital verde e, por sua vez, a certificação LEED.

Clinical characteristics of different histologic types of breast cancer.

Breast cancer is a heterogeneous disease, though little is known about some of its rarer forms, including certain histologic types. Using Surveillance, Epidemiology, and End Results Program data on 135 157 invasive breast cancer cases diagnosed from 1992 to 2001, relationships between nine histologic types of breast cancer and various tumour characteristics were assessed. Among women aged 50-89 years at diagnosis, lobular and ductal/lobular carcinoma cases were more likely to be diagnosed with stage III/IV, > or =5.0 cm, and node-positive tumours compared to ductal carcinoma cases. Mucinous, comedo, tubular, and medullary carcinomas were less likely to present at an advanced stage. Lobular, ductal/lobular, mucinous, tubular, and papillary carcinomas were less likely, and comedo, medullary, and inflammatory carcinomas were more likely to be oestrogen receptor (ER) negative/progesterone receptor (PR) negative and high grade (notably, 68.2% of medullary carcinomas were ER-/PR- vs 19.3% of ductal carcinomas). In general, similar differences were observed among women diagnosed at age 30-49 years. Inflammatory carcinomas are associated with more aggressive tumour phenotypes, and mucinous, tubular, and papillary tumours are associated with less aggressive phenotypes. The histologic types of breast cancer studied here differ greatly in their clinical presentations, and the differences in their hormone receptor profiles and grades point to their likely different aetiologies.

Distribution and diversity of cry genes in native strains of Bacillus thuringiensis obtained from different ecosystems from Colombia.

Colombia is a tropical country located at the north of South America. It is considered to be one of the most important countries in terms of its biodiversity worldwide. One hundred and eight soil samples obtained from agricultural crops and wild ecosystems were evaluated in terms of the presence of Bacillus thuringiensis (Bt) native strains. One hundred and eight different Bt strains were isolated and characterized by the presence of crystal proteins by SDS-PAGE and a multiplex PCR with general and specific primers for cry1 and cry3, cry7, and cry8 gene detection. Most of the Bt strains (73%) reacted with the cry1 general primers; 27.8% of the Bt strains reacted with cry3, cry7, and cry8 general primers and 17.8% of strains did not react with any of these two sets of primers. Thirty different PCR profiles were found in the strains with cry1 genes when they were analyzed with specific primers (cry1A to cry1F). A high frequency of joint occurrence was observed for cry1Aa/cry1Ab, cry1Aa/cry1Ac, cry1Ab/cry1Ac, and cry1C/cry1D genes with a Pearson coefficient of 0.88, 0.74, 0.76, and 0.87, respectively. Other distinctive characteristics were found in the Colombian collection as the presence of 22.2% of native strains which presented, at the same time, lepidopteran and coleopteran active genes. Interesting relations were found as well between the cry gene distribution and the geographical areas sampled. Finally, some strains with moderate to high biopesticide activity against Spodoptera frugiperda (Lepidoptera) and Premnotrypes vorax (Coleoptera) insects were identified, this being important to explore future microbial strategies for the control of these crop pests in the region.

Hallazgos cistométricos en pacientes diabéticos / Cistometrogram results in diabetic patients

Se revisan los hallazgos cistométricos en 12 pacientes diabéticos (15 hombres y 17 mujeres) evaluados por alteraciones miccionales en la Unidad de Urodinamia del Hospital del Salvador entre 1995 y agosto de 1997. Encontramos cistopatía clásica en un 41 por ciento de los pacientes, inestabilidad del detrusor en un 30 por ciento y arreflexia vesical en 6 por ciento. El estudio fue normal en 7 pacientes (22 por ciento). Consideramos el examen cistométrico importante en la evaluación del paciente diabético con síntomas miccionales antes de iniciar su tratamiento

Hematoma perirrenal espontáneo / Spontaneous perirenal hematoma

Esta es nuestra experiencia en 8 casos de hematoma perirrenal espontáneo. Dolor lumbar, masa palpable e hipotención son características clínicas frecuentes en estos pacientes. El estudio se inicia con pielografía de eliminación, siendo la tomografía axial computada y la arteriografía de mayor utilidad para establecer la etiología, aun cuando en más del 50 por ciento no es posible hacerlo, y tenemos que considerar que un adenocarcinoma pequeño puede ser la causa, especialmente si encontramos un hematoma subcapsular. La cirugía conservadora es el tratamiento de elección, a menos que encontremos un adenocarcinoma. En 3 pacientes se hizo nefrectomía primaria por tumor renal. En 2 pacientes se realizó nefrectomía secundaria, una por trombosis de la arteria renal posterior a la reparación de un aneurisma y otra en un paciente que presentó recidiva del hematoma perirrenal no lográndose establecer la causa