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Given that hypothermia cases have occurred in newborns after MRI with anesthesia and reproducing what was observed in centers visited overseas, we implemented a supervised protocol to evaluate the results of cerebral MRI performed without anesthesia or sedation in patients hospitalized in our institution. Objective: To display results of the protocol for performing cerebral MRI without anesthesia in our newborn patients. Materials and methods: A retrospective study, we evaluated cerebral MRI performed on newborns from september 2012 - july 2013. Protocol for performing MRI without anesthesia was applied in institutionalized patients. Variables are compared with MRI performed using anesthesia, during this period. Results: 22 cerebral MRI were performed, 14 without anesthesia. The duration of the study without anesthesia was 48 minutes on average, obtaining adequate images in 13 studies, reprogramming the examination with anesthesia in one case. Conclusions: The protocol implemented allows the acquisition of diagnostic-quality cerebral MRI, obviating the anesthesia.

Dado casos de hipotermia en recién nacidos (RN) posterior a resonancia magnética (RM) con anestesia y reproduciendo lo observado en centros extranjeros visitados, implementamos protocolo supervisado para evaluar los resultados de RM encefálicas realizadas sin anestesia o sedación en pacientes hospitalizados en nuestra institución. Objetivo: Mostrar resultados del protocolo para realización de RM encefálica sin anestesia en nuestros pacientes RN. Materiales y métodos: Estudio retrospectivo, evaluamos RM encefálicas realizadas en RN entre septiembre 2012 - julio 2013. Se aplicó protocolo para realización de RM sin anestesia en pacientes institucionalizados. Se comparan variables con RM realizadas con anestesia en ese periodo. Resultados: Se realizaron 22 RM encefálicas, 14 sin anestesia. La duración del estudio sin anestesia fue de 48 minutos promedio, obteniendo imágenes adecuadas en 13 estudios, reprogramando el examen con anestesia en un caso. Conclusiones: el protocolo implementado permite obtener RM encefálicas de calidad diagnóstica, obviando la anestesia.

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The major concern of the present article is research into the combination of analytical assessment and multi-correlative data interpretation. For this purpose, a high performance liquid chromatography (HPLC) procedure was developed for the simultaneous quantification of salicin, salicylalcohol derivatives, phenolic acids, flavonoids, and monomeric catechins after solid phase extraction (SPE). On the basis of an established and validated HPLC method, 49 different Salix samples were extracted, purified, and analysed. Furthermore, the quantity of total polyphenols (Folin-Ciocalteau colorimetric reaction) and the antioxidant activity (DPPH radical scavenging activity test) were determined and correlated. This yielded correlation coefficients at P-values less than 0.05 of 0.775, 0.967, 0.932, and 0.989 for Salix fragilis, Salix rubens, Salix purpurea (2006), and Salix purpurea (2007), respectively. Correlation with mean values of each species between total polyphenols content and % DPPH inhibition values occurred at a correlation coefficient (r) of 0.851. Linear correlations of quantified HPLC data with DPPH data and with total polyphenols content could also be found for salicin, gentisic acid, naringin, and salicylic acid. Finally, by combining HPLC data with total polyphenols content and antioxidant capacity through 3-D scatter plots and FreeViz data projection, it was shown that primarily the amount of epicatechin and saligenin beside DPPH values and total polyphenols content enable the classification into plant species and further by year of harvest.

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In the paper we demonstrate a new approach for the preparation and application of continuous silica bed columns that involve encapsulation (entrapment) of functionalized silica microparticles, which can be used as packing material in micro high performance liquid chromatography (micro-HPLC) and capillary electrochromatography (CEC). Like traditional packed columns, these capillaries possess characterized silica particles that offer high phase ratio and narrow pore size distribution leading to high retention and separation efficiency, respectively. More importantly, immobilization of the microparticles stabilizes the separation bed and eliminates the need for retaining frits. The developed capillary columns were fabricated in exactly the same way as a packed capillary column (slurry packing) but with an additional entrapment step. This immobilization of the packed bed was achieved by in situ polymerization of styrene and divinylbenzene in presence of decanol as a porogen and azobisisobutyronitrile as thermal initiator. Silica particles with different particle sizes and pore sizes ranging from 60 to 4000 A were studied. In addition different modified silica was used, including C-18 reversed phase, anion exchange and chiral stationary phases. Efficient separation of polyphenolic compounds, peptides, proteins and even DNA mutation were achieved using the developed technique depending on the properties of the silica particles used (particles pore size). For example, using 3 microm ProntoSIL C-18 particles with 300 A pore size, separation efficiencies in the range of 120,000-200,000 plates/m were obtained for protein separation, in a 6 cm x 200 microm i.d. capillary column. Using encapsulated silica C-18 with 1000 A pore size, separation of DNA homo and hetero duplexes were achieved under denaturing HPLC conditions for mutation detection. In addition, nucleotides were separated using anion exchange material encapsulated with poly(styrene-divinylbenzene) (PS/DVB), which indicated that the chromatographic properties of the silica packing material were still active after polymerization. The prepared capillary columns were found to be stable and could easily be operated continuously up to a pressure of 350 bar without column damage and capillary can be cut to any desired length.

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Silica particles of different porosity were functionalised with iminodiacetic acid (IDA) and loaded with Cu(II) ions to yield Cu(II)-IDA-silica. These immobilised metal affinity chromatography (IMAC) materials were subjected to a comprehensive characterisation study. The Cu(II) content--determined via UV/Vis spectroscopy and atomic absorption spectroscopy (AAS)--was found to be linearly dependent on the specific surface area of the silica particles. The evaluation of protein adsorption isotherms provided information on binding properties towards biomolecules. The data fitted Langmuir's adsorption theory. Binding capacity of hen egg white lysozyme (HEWL) was highest for Cu(II)-IDA-silica with mean pore diameter of 120 A, reaching nearly 350 mg/g. All derivatised materials were applied to the fractionation of human serum samples and subsequent mass spectrometric analysis (m/z: 2000-10,000) according to a surface-enhanced affinity capture (SEAC) protocol. Pore size of the support material affected the appearance of the mass spectra to a great extent, showing that surface morphology is another parameter that has to be considered in addition to surface chemistry. Signal intensity as well as the number of detected masses were strongly dependent on the pore diameter, indicating that the carrier material has to be carefully chosen to assure best results.

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Silica particles of different porosity were functionalised with iminodiacetic acid (IDA) and loaded with Fe(III) to yield immobilised metal affinity chromatography stationary phases (Fe(III)-IDA-silica) for phosphopeptide enrichment. The elution step of bound phosphopeptides was optimised with a 32P radioactive labelled peptide by a comprehensive study. Several elution systems, including phosphate buffers of different pH and concentration and ethylenediaminetetraacetic acid solutions were employed. Furthermore the effect of support porosity on elution behaviour was investigated. Under best conditions recoveries higher than 90% were achieved. A solid-phase extraction (SPE) protocol was developed for fractionation of phosphorylated and non-phosphorylated peptides and desalting of the fractions which is essential for subsequent mass spectrometric analysis by the combination of Fe(III)-IDA-silica and C18-silica particles. The pH of the loading buffer was found to be a critical parameter for the efficiency of the SPE protocol. As tryptic digests of alpha-lactalbumin, lysozyme and ribonuclease A mixed with three synthetic phosphopeptides were fractionated, pH 2.5 provided minimal proportion of unspecific bound peptides when comparing the fractions after mu-LC-electrospray ionization MS separation. The effect of a sample derivatisation reaction (methylation) on the efficiency of phosphopeptide enrichment was further investigated. Blocking carboxylate groups by methyl ester formation totally prevented unspecific interaction with the immobilised Fe(III) ions, but generated partially methylated phosphopeptides that increased the complexity of the phosphorylated fraction.

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La prevalencia mundial de obesidad ha tenido un aumento sostenido, en las últimas tres décadas, llegando a ser pandémica. Actualmente en Chile, uno de cada cuatro niños y adolescente es obeso y uno de cada tres está en riesgo de serlo, siendo en ellos factor de riesgo de enfermedades, que inciden directamente en el desarrollo global. Los estudios han concluido que la única forma de revertir esta tendencia es por cambios del estilo de vida, con énfasis en la educación. Basado en lo anterior, el objetivo fue determinar el comportamiento de indicadores de evaluación nutricional en escolares rurales, intervenidos con estrategias educativas de promoción. Personas y Métodos. Investigación/acción, en niños preescolares, primero y segundo ciclo básico (n=256) de un colegio rural de Melipilla, a través de dos evaluaciones del estado nutricional diagnóstica (END) y final (ENF) realizada por internos del programa Internado Rural, Carrera de Medicina, U de Chile. Se midió en forma estandarizada el peso y la talla. La intervención en promoción de la salud, -diez meses-, fue realizada por los profesores jefes y de educación física. Resultados. Globalmente, END fue 36 por ciento bajo peso; 56,7 por ciento eutróficos; 24,6 por ciento sobrepeso y 15,2 por ciento obesos. No hubo desnutridos ni obesos severos. En la ENF se encontró un niño desnutrido (0,4 por ciento); 6,5 por ciento de bajo peso; 48,8 por ciento eutróficos; 37,1 por ciento sobrepeso y 7,3 por ciento obesos. La disminución de obesos fue significativa, acompañándose de un aumento de niños con sobrepeso. las variaciones en los eutróficos y niños con bajo peso fueron significativas. Se presentan los resultados, con similar tendencia, desagregados por cada ciclo. Discusión. Se evidencian la preocupante situación nutricional de los niños evaluados, concordando con las cifras de la OMS. Los resultados de la evaluación mostraron una tendencia a la disminución de obesos, y un aumento de niños con sobrepeso. Lo anterior podría ser por un desplazamiento de la curva total de los niños hacia el sobrepeso, a expensa de la disminución de obesos y eutróficos o por el especial manejo de los obesos en quienes se realizan acciones más dirigidas a fin de disminuir su problema. La situación epidemiológica actual amerita, fortalecer las acciones de promoción de estilos de vida saludables ya que los resultados terapéuticos siguen siendo poco alentadores.

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El diagnóstico de las enfermedades cardiovasculares es un tema en constante investigación, dada su relevancia en la práctica médica, al ser ésta la primera causa de muerte en los países desarrollados. En el caso de la patología coronaria el mejor método de estudio sigue siendo la angiografía coronaria, dadas su mejor sensibilidad y especificidad. Sin embargo la tendencia es disminuir su uso, restringiendo su indicación a casos seleccionados debida la morbimortalidad que se asocia a esta técnica. En este artículo presentamos una revisión sobre el desarrollo de la imagenología en el estudio no invasivo de la patología coronaria, centrándonos en lo portado por la resonancia magnética y la tomografía computarizada; ambas técnicas muy provisorias, aunque sin valor clínico probado.

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Las afecciones del tejido conectivo corresponden a un grupo de síndrome autoinmunes que determinan daño tisular. Estas afecciones son más frecuentes en mujeres, por lo que su relación con el embarazo debe ser considerada. Se revisan aspectos patogénicos, clínicos, evolutivos del embarazo y de la mesenquimopatías en pacientes con lupus eritematoso sistémico (LES), artritis reumatoídea (AR), esclerosis sistémica progresiva (ESP) y síndrome antifosfolípidos (SAF). El lupus eritematoso sistémico implica a un alto riesgo de morbilidad y mortalidad perinatal. La artritis reumatoide mejora su sintomatología en un elevado porcentaje de embarazadas. La esclerosis sistémica por su edad de presentación se asocia poco a gestación, pero de hacerlo puede ocacionar en algunas mujeres un desenlace fatal. El síndrome antifosfolípidos se asocia a abortos o pérdidas fetales recurrentes sin causa obstétrica.

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El priapismo es una erección anormal y persistente del pene, dolorosa e involuntaria, sin relación con estímulos sexuales y que no se alivia con la descarga de catecolaminas después del orgasmo. Según su mecanismo fisiopatológico se reconoce un priapismo isquémico o de bajo flujo y uno no isquémico o de alto flujo. Es muy importante diferenciarlos, ya que tienen causas y tratamientos distintos. El priapismo isquémico es una urgencia que debe ser resuelta a la brevedad. Su tratamiento debe ser secuencial, siguiendo un algoritmo y tratando de evitar acciones que aumenten el riesgo de una disfunción eréctil iatrogénica posterior. El priapismo de alto flujo no es una urgencia médica, por lo que su manejo inicial debe ser expectante. A pesar de ser poco frecuente, el priapismo debe ser conocido por el mÚdico general, quien debe ser capaz de diferenciar los casos isquémicos de los no isquémicos y de tratarlos de manera de evitar secuelas y disfunciones sexuales posteriores. Se propone un algoritmo de acuerdo a las recomendaciones de la Asociación Americana de Urología. En él se establecen las medidas a tomar en un orden secuencial que va aumentando en complejidad y el empleo de procedimientos invasivos.

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La patología cardiovascular ha adquirido una importancia creciente en el último tiempo, debido a que es la principal causa de muerte en países desarrollados. Esto ha llevado al desarrollo de múltiples estudios dentro de los que destacan aquellos que asocian los niveles plasmßticos basales de Proteína C reactiva (PCR) con el riesgo cardiovascular y la magnitud de su aumento durante un evento coronario con el pronóstico del paciente. Valores elevados de la línea basal de PCR se han visto asociados a síndromes metabólicos, lo que sugiere que el aumento de los marcadores de inflamación puede reflejar un estado metabólico particular que resulta ser también proaterogénico y/o predisponer a los eventos aterotrombóticos. Esta asociación es especialmente valiosa en los pacientes sin factores de riesgo tradicionales, porque nos permitiría pesquisarlos y realizar una prevención activa de futuros eventos aterotrombóticos.En esta revisión se explican los conceptos actuales tras una dÚcada de investigación, haciendo hincapié en la gÚnesis del proceso patológico, la utilidad clínica de la PCR tanto en la prevención como en el pronóstico de la patología aterotrombótica y las interrogantes que persisten.

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La neumonía asociada a ventilación mecánica invasiva es un tema de gran importancia en la práctica médica intensivista, ya que constituye un subgrupo de las neumonías intrahospitalarias que destaca por su alta prevalecía y morbimortalidad, observándose como complicación en un 8 a 28 por ciento de los pacientes conectados a ventilación mecánica. La tasa de referencia nacional de neumonía asociada a ventilación es de 19,5 neumonía intrahospitalaria por 1.000 días de ventilación mecánica. En el hospital San Juan de Dios se ha realizado un seguimiento de estos casos dentro del programa de infecciones intrahospitalarias, en el informe del quinquenio 1996-2000 se describe que este índice alcanzo un 49,2 con una la letalidad que varió entre 27,6 a 61,1 por ciento, siendo la letalidad atribuible entre 3,2 por ciento y 13,3 por ciento. Dada la alta tasa de neumonía asociada a ventilación que existe en nuestra unidad de cuidados intensivos (UCI) se realizó una revisión de este tema, abordando su génesis como proceso patológico y sus etiologías más frecuentes a nivel local; así como los recursos diagnósticos disponibles y las bases para un manejo oportuno.

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To investigate probable health benefits of flavonoids and stilbenes in red wine a new reversed-phase (RP) high-performance liquid-chromatographic (HPLC) method with enhanced separation efficiency and improved selectivity, sensitivity, and speed has been established for determination of the flavonoids quercetin, myricetin and kaempferol and the stilbenes cis- and trans-resveratrol, in a single run . UV-absorbance, fluorescence (FLD), and mass-spectrometric (MS) detection were also evaluated. UV-absorbance detection at 320 nm for stilbenes and 377 nm for flavonoids enables their determination up to the nanogram range with a linearity of R2>0.9999 (linear range 50 ng mL(-1)-50 microg mL(-1)). Calculated values of average recoveries were between 95 and 105% for all analytes. For resveratrol, fluorescence detection was highly selective and twice as sensitive as UV detection, and linearity was satisfactory (R2>0.9996; linear range see UV detection). For the detection of the hydrophilic glycosidic compounds piceid and rutin, which are coeluted with other hydrophilic ingredients, the validated RP HPLC system was coupled to a quadrupole ion-trap mass-spectrometer (MS) via an electrospray interface (ESI) with 25% ammonia solution as sheath liquid. MS detection was, highly linear (R2>0.9878; linear range 50 ng mL(-1)-50 microg mL(-1)) for all investigated analytes and the limits of detection were in the low nanogram range. Compared with UV detection MS detection resulted in a 200% increase in signal intensity for myricetin and 400% increases for quercetin and kaempferol, but equal signal intensity for resveratrol. Calculated values of average recoveries were 102% for myricetin and 79% for piceid. Collision induced dissociation (CID) was also used to obtain characteristic fragmentation fingerprints to facilitate qualitative and quantitative analysis even in complex matrices. Finally, this hyphenated HPLC-ESI-MS method was highly suitable and an essential improvement compared with UV- and fluorescence detection.

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Background: All winters, there is an increase in the number of pediatric consultations, associated to three factors: cold weather, air pollution and respiratory virus epidemics. Aim: To study the influence of these three factors in the demand for pediatric consultations between march and september, in an area of Metropolitan Santiago. Patients and Methods: The number of consultations between march and september 1998 in the emergency room and the number of hospital discharges due to lower respiratory tract infections, were registered in a public pediatric hospital of Santiago. A respiratory virus surveillance (respiratory syncytial virus, adenovirus, influenza and parainfluenza virus) was done among children admitted for lower respiratory infections. Atmospheric temperature values and air pollution, measured as the number of particles of 10 µm or more per m3 (MP 10), were obtained from local health services. Results: Two elevation waves of outpatient consultations were detected at weeks 19 and 26, that coincided with the periods of maximal detection of influenza and syncytial respiratory virus, respectively. The epidemics of respiratory syncytial virus coincided with the maximal number of hospital admissions for lower respiratory tract infections at week 27. There was no correlation between air pollution and the number of pediatric consultations. The lower ambient temperatures coincided with the higher detection of respiratory syncytial virus at week 28, moment in which the demand for consultations or hospital admissions was descending. Conclusions: There is a direct relationship between respiratory virus epidemics and the demand for pediatric consultations. There is also a minor influence of ambient temperature

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INTRODUCTION: Quantitative DNA cytophotometry, the study of morphology of chromosomes and cell kinetics are important approaches toward characterization of genetic information. Each approach has its own problems and limits. Difficulties with interpretation of DNA histograms arise from a lack of proper terminology, and from attempting to interpret them in terms of the existing terminologies for chromosomal analysis and cell kinetics. Aim of this research was to develop a computerized mathematical analysis of DNA histograms. MATERIALS AND METHODS: As a basis for the comparison of normal with those of tumor cell populations the DNA histograms of heart muscle cells were selected for the normal cell population from 14 normal hearts of adults, 16 hypertrophic hearts, 14 non-polyploidized hearts of children, and 14 hypertrophic hearts of children with congenital malformations. Normal diploid cell populations from 7 effusions were also included. The 24 populations of malignant cells consisted of primary tumors and metastatic effusions. DNA cytophotometry was performed on single nuclei in Feulgen stained preparations by means of the UMSP/XD 50 ZEISS. The approximation of the DNA histograms by linear combination of normal distributions was done according to spline-function and calculated by means of the IBM-375. RESULTS: The nuclear classes 2C, 4C, and 8C show no differences between the normal, left and right heart with respect to mean values (X), standard deviations (sx), variances (sX) and coefficients of variance (sx/X). However, coefficients of variance are smaller in hypertrophic (2.15 to 8.37%) than in normal hearts of adults (8.90 to 10.85%), and larger in hypertrophic heart of children (4.06 to 7.09%). The mean values of the DNA classes 2C, 4C, 8C, and 16C vary witin +/- 18.6% with a probability of 95.5%. Benign effusions contain only 2C and 4C nuclei with a variance of 4.00% and 8.75%, respectively. In DNA histograms of malignant cells, only one third has a first peak outside of 2C +/- 18.6%. In approximately one fifth of the histrograms the position of the second or third peaks deviates significantly from normal polyploid values. Since a large proportion of polyploid nuclei is limited to only a few normal tissues, pronounced polyploidy is suggestive of malignancy in all other tissues. If in the cases containing only two DNA classes, 2C and 4C, the populations are malignant, the proportion of 4C is more than 8% while in the corresponding benign populations the proportion of 4C atains only 2.97 +/- 2.5%. In some cases a few highly polyploidized nuclei not taken into a account by our computer program are suggestive of malignancy. In only one DNA histogram out of the 24 analysed, all of these criteria are negative. In six cases the computer analyses reveal two stemlines of tumor cells with corresponding polyploid values.

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MATERIAL AND METHODS: The growth and the regression of the experimental tumor S 180 was investiaged by volume measurements and by cytophotometric studies on 50 mice in each of a pilot and in the present main experiment. In addition, histological, cytological and cytokinetic examinations were performed. RESULTS AND DISCUSSION: Beginning on day 18, a spontaneous regression of the tumor was found in 20% and 38% of the animals, respectively. DNA-measurements were performed with a scanning-microspectrophotometer on tumor tissue imprints and tumor cell suspensions and were also carried out with a flow-through cytophotometer ICP on suspensions. DNA-histograms were plotted on days 4, 7, 12, 18, 20, 22, 26 and 29 after the transplantation. These revealed a constant position of the maxima at 2C for normal cells and at 4C and 8C for the tumor cells. In particular, by measuring a large total number of 4,968,000 nuclei with the ICP, distinct changes were found in the proportion of the single nuclei classes during growth and spontaneous regression. This technique also enables a quantitative measurement to be made of the DNA of cell debris from necrosis. With growing tumos, the proportion of the tumor cells increased to a maximum of 65% on day 18 and decreased to 37% on day 29. The DNA of cell debris grew from 8% to 47%. The proportion of normal cells was only 10% to 15% in the final phases. In tumors with a spontaneous regression the proportion of the tumor cell nuclei was 20% on day 18 and 11% on day 29. The proportion of the DNA of cell debris was again about 45%. The proportion of normal nuclei was greatly increased to 45%. Histological and cytological evidence together with measurements of the areas of nuclei and incorporation of 3H-TdR confirmed that the normal cells, the number of which increased during spontaneous regression were cells of a fibrovascular granulation tissue. While the rate of the DNA-synthesis of growing tumors continously decreased with age there was also a rapid decrease of the labelling index of spontaneously regressing tumors between days 12 and 18. In the final phase only the nuclei of the granulation tissue were labelled.

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