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In this document we present the differences in the Zeta potential and in the Infrared spectra data obtained from the characterization of silanized titanium dioxide particles, using two different solvents as reaction media: ethanol and toluene. Also, we provide micrographs of transmission electron microscopy in order to show morphological differences between the analyzed samples.

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OBJECTIVE: There is an increasing search for antibiofilm agents that either have specific activity against biofilms or may act in synergy with antimicrobials. Our objective is to examine the the antibiofilm properties of stingless bee honeys. METHOD: Meliponini honeys from Costa Rica were examined along with Medihoney as a reference. All honeys were submitted to a screening composed of minimum inhibitory concentration, inhibition of biofilm formation and biofilm destruction microplate-based assays against a Staphylococcus aureus biofilm forming strain. Dialysis led to the isolation of an antibiofilm fraction in Tetragonisca angustula honeys. The honey antibiofilm fraction was evaluated for protease activity and for any synergistic effect with antibiotics on a Staphylococcus aureus biofilm. The active fraction was then separated through activity guided isolation techniques involving SDS-PAGEs, anion exchange and size exclusion fast protein liquid chromatographies. The fractions obtained and the isolated antibiofilm constituents were tested for amylase and DNase activity. RESULTS: A total of 57 Meliponini honeys from Costa Rica were studied in this research. The honeys studied belonged to the Tetragonisca angustula (n=36) and Melipona beecheii (n=21) species. Costa Rican Tetragonisca angustula honeys can inhibit the planktonic growth, biofilm formation, and are capable of destroying a Staphylococcus aureus biofilm. The antibiofilm effect was observed in the protein fraction of Tetragonisca angustula honeys. The biofilm destruction proteins allowed ampicillin and vancomycin to recover their antimicrobial activity over a Staphylococcus aureus biofilm. The antibiofilm proteins are of bee origin, and their activity was not due to serine, cysteine or metalloproteases. There were 2 proteins causing the antibiofilm action; these were named the Tetragonisca angustula biofilm destruction factors (TABDFs). TABDF-1 is a monomeric protein of approximately 50kDa that is responsible of the amylase activity of Tetragonisca angustula honeys. TABDF-2 is a protein monomer of approximately 75kDa. CONCLUSION: Tetragonisca angustula honeys from Costa Rica are a promising candidate for research and development of novel wound dressings focused on the treatment of acute and chronic Staphylococcus aureus biofilm wound infections.

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INTRODUCTION: The veno-arteriolar reflex (VAR) is triggered by an increase in the transmural venous pressure on placing a part of the body in the same direction as the gravitational acceleration below the heart. AIM: To assess the VAR in healthy subjects on raising a part of the body above the level of the heart. SUBJECTS AND METHODS: VAR was studied in 16 healthy subjects (20-65 years old) by means of changes in the blood flow in the skin detected using a digital infrared photoplethysmograph attached to the fingertip under the following conditions: right arm at the height of the heart, right arm below the heart and right arm below the level of the heart. The variables measured were: amplitude of the blood flow in the skin with the arm raised to the height of the heart (baseline amplitude), percentage decrease of the blood flow in the skin with the arm below the heart and percentage increase in blood flow with the arm above the heart. RESULTS: The percentage of vasoconstriction with the right arm below the heart was 35%, and that of vasodilation, 50%. CONCLUSIONS: Evaluation of the VAR with the arm below the heart causes vasoconstriction, and elevation of the arm causes an important degree of vasodilation. Vasoconstriction and vasodilation are maintained while the limb is kept above or below the heart. This is an economical and potentially very useful way of studying the innervation of the microcirculation in a number of different peripheral neuropathies of thin and mixed fibres.

TITLE: Las dos caras del reflejo venoarteriolar: vasoconstriccion y vasodilatacion cutanea al bajar y subir el brazo.Introduccion. El reflejo venoarteriolar (RVA) lo provoca un incremento en la presion venosa transmural al colocar una parte del cuerpo en el sentido de la aceleracion gravitatoria por debajo del corazon. Objetivo. Evaluar el RVA en sujetos sanos al levantar una parte del cuerpo por encima del corazon. Sujetos y metodos. En 16 sujetos sanos (20-65 años) se estudio el RVA mediante cambios en el flujo sanguineo de la piel con un fotopletismografo digital infrarrojo colocado en el pulpejo en sujetos sanos durante las siguientes condiciones: brazo derecho a la altura del corazon, brazo derecho 40 cm por debajo del corazon y brazo derecho 40 cm por encima del corazon. Las variables medidas fueron: amplitud del flujo sanguineo de la piel con el brazo a la altura del corazon (amplitud basal), porcentaje de disminucion del flujo sanguineo de la piel con el brazo por debajo del corazon y porcentaje de aumento del flujo sanguineo de la piel con el brazo por encima del corazon. Resultados. El porcentaje de vasoconstriccion con el brazo derecho por debajo del corazon fue del 35%, y el de vasodilatacion, del 50%. Conclusiones. La evaluacion del RVA con el brazo por debajo del corazon provoca vasoconstriccion, y la elevacion del brazo produce una importante vasodilatacion. La vasoconstriccion y la vasodilatacion se mantienen mientras la extremidad se mantenga por encima o por debajo del corazon. Este es un estudio potencialmente muy util y economico para estudiar la inervacion de la microcirculacion en diversas neuropatias perifericas de fibras delgadas y mixtas.

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Resumen: Introducción: Observamos que el compromiso axilar es uno de los factores de pronóstico más importantes. Aunque la asociación entre el compromiso axilar y el tamaño tumoral ha sido estudiada en varias series, la relación del subtipo según la inmunohistoquímica (IHQ) para predecir compromiso axilar, no es muy conocida. El objetivo de este estudio es correlacionar los subtipos intrínsecos según la IHQ con la afectación axilar. Como objetivos secundarios evaluamos la sobrevida global y libre de enfermedad. Material y métodos: Se incluyeron en este estudio 1.413 pacientes operadas en forma consecutiva en el Hospital Italiano de Buenos Aires con diagnóstico de cáncer de mama primario (se excluyeron los estadios IV) entre los años 2007 y 2012. Fueron analizados los datos clínicos y patológicos de las pacientes que realizaron la biopsia del ganglio centinela o la linfadenectomía axilar. Los subtipos se clasificaron en cuatro grupos según la IHQ: luminal A (RE+, RP+, HER–, Ki67 <15%); luminal B (RE+, RP+, HER+, Ki67 >14%); HER2 (RE–, RP–, HER+); y triple negativo (RE–, RP–, HER–). Resultados: Evaluamos 1.413 pacientes de las cuales se analizaron 1.248 casos, donde 386 casos (31%) mostraron metástasis en los ganglios axilares. Tomando como referencia al grupo luminal A encontramos que la presencia de compromiso axilar es significativo en aquellos subtipos luminal B y HER (p<0,0001), no así en el subtipo TN (p=0,4468). Mediante un modelo de regresión logística múltiple se evaluó la probabilidad de compromiso axilar ajustado por cada uno de los diferentes subtipos tumorales, tamaño tumoral. En aquellos tumores menores de 2 cm observamos que los tumores luminal B y los TN aumentan el riesgo de compromiso axilar con un OR=2,73 (95% IC: 1,73-4,31; p>0,000), y un OR=2,05 (95% IC: 1,13-3,70; p=0,017), respectivamente, y los tumores HER2 aumentan el riesgo con un OR=6,62 (95% IC: 3,02-14,50; p>0,000).

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Honey is the principal apiculture product, produced by Apis mellifera bee. This, as any other food product, has to accomplish certain quality standards, including physicochemical, organoleptic and microbiological properties. Within these parameters, different measures are considered as adulteration indicators, including hydroxymethylfurfural and diastase enzyme activity which are associated to overheating, and the sucrose, glucose and fructose content. In this study, a determination of previous parameters, additional to glucose, fructose and fructose/glucose index was performed to 35 artisan samples, obtained directly from beekeeper, previously characterized as having good productive practices and 25 commercial samples. Same time, the results obtained were compared and interpreted, in order to determine the kind of adulteration present in the honey sample. The 89% of artesian samples accomplished the parameters established by the Codex Alimentarius for HMF content, diastase activity, sucrose and simple sugars content. Nevertheless, only 20% (5) of the commercial samples accomplished the international and national normative. 24% of these samples presented succrose addition, 32% overheating or inverted sugar syrup addition, and 24% were adulterated with inverted sugar syrup.

La miel es el principal producto de la apicultura, generado por la abeja Apis mellifera. Éste, como cualquier producto alimenticio, debe cumplir con ciertas normas de calidad, propiedades fisicoquímicas, organolépticas y microbiológicas. Entre estos parámetros se encuentran el contenido de hidroximetilfurfural (HMF), indicador de adulteración, sobrecalentamiento y envejecimiento de la miel, la actividad de la enzima diastasa, indicador de sobrecalentamiento, y la determinación de contenido de sacarosa y azúcares simples, indicadores de adulteración. En el presente estudio, se procedió a determinar los anteriores parámetros, además del contenido de glucosa, fructosa e índice fructosa/glucosa a 35 muestras de mieles artesanales obtenidas directamente del apicultor, previamente catalogado como productor con buenas prácticas y 25 de mieles distribuidas en expendios. A su vez, se compararon los resultados poblacionales obtenidos y se les interpretó, con el objetivo de determinar el tipo de alteración que presentara la miel. Se determinó que 89% de las mieles control cumplieron con los parámetros establecidos por el Codex Alimentarius para su contenido de HMF, actividad de diastasa, contenido de sacarosa y de fructosa y glucosa. Contrario, sólo el 20% (5) de las mieles comerciales logró cumplir los estándares internacionales y la normativa nacional. Se destaca que un 24% de las muestra comerciales presentan adición de sacarosa y glucosa, 32% sobrecalentamiento o adulteración con sirope de azúcar invertido, y 24% adición de jarabe de azúcar invertido.

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OBJECTIVE: High urinary Prostaglandin E2 (PGE2) and thromboxane B2 (TxB2) levels have been reported in lupus nephritis (LN). Captopril diminishes proteinuria and improves glomerular filtration rate (GFR), and may have effect on immune function. We evaluate captopril effect on urinary PGE2, and TxB2. METHODS: Eighteen LN patients were randomly assigned to two groups. Group 1 received only prednisone plus cyclophosphamide. Group 2 received also captopril. Serum creatinine, GFR, RPF, urinary proteins, PGE2 and TxB2, were assessed. RESULTS: There were no differences between the initial and final assessments in Group 1. Group 2 showed a significant decrement in proteinuria (p=0.003) and serum creatinine (p=0.01) at the end of the study. PGE2 decreased significantly when compared with the initial value (p=0.02). CONCLUSION: Captopril plus usual treatment, improved serum creatinine and decreased proteinuria in parallel with prostaglandin E2 reduction. This effect is not related to changes in GFR or RPF. Captopril may have an immunomodulatory effect on local inflammatory processes in lupus nephritis.

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En los últimos años se ha visto como las células madre han pasado de ser un concepto de interés científico, a ocupar tantas páginas en las revistas científicas como esperanzados comentarios en la prensa. Los conocimientos que en este campo de la medicina se vienen produciendo de forma casi diaria han disparado las expectativas de los enfermeros y de los médicos de que las células madre vayan a contribuir a la curación de múltiples enfermedades humanas como la diabetes, la enfermedad de Parkinson, el infarto de miocardio u otras muchas. En el centro del debate científico, político y ético se ha situado la utilización e investigación con células madre embrionarias. No obstante, ante el descubrimiento de células madre adultas, ya sean del propio enfermo o de un donador, pareciera que existen menos obstáculos en el campo ético más grados de libertad para el investigador y ciertamente mayores esperanzas para los enfermos. Es por esta razón, que vamos a comentar algunos de los aspectos básicos sobre este tema, en especial, en el interés que ha provocado la terapia con células madre en la reparación de corazones lesionados.

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Despite the growing interest in enhancing the cultural awareness for nurse practitioner (NP) students who work with patients from the developing world, there is a dearth of reports on such experiences. This report describes the clinical experiences of NP students from George Mason University (Fairfax, VA) during an intensive 2 weeks in Nicaragua in their final semester, accompanied by an NP faculty member. The program was planned and implemented in collaboration with the Universidad Politecnica de Nicaragua School of Nursing (Managua, Nicaragua). The students' clinical experiences included working in a Health Post and an impoverished community. Students learned to manage clinical problems using minimal resources and acquired an appreciation for the cultural, political, and economic situations from which many of their patients in the United States originate. Recommendations for establishing this type of experience are included.

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Realizou-se estudo das propriedades gerais da ondansetrona. A estabilidade térmica do sólido é ensaiada mediante determinação do comportamento termogravimétrico e do ponto de fusão. A descrição das características e a interpretação do comportamento térmico são complementadas por meio de estudos espectrométricos: IV, RMH-Hû, RMN-ûüC, UV-VIS e fluorescência

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BACKGROUND: The degree of disability of workers ascribed to the private allowances system in Chile, is judged by Medical Commissions that apply norms that establish percentages of incapacity, without considering prognosis. AIM: To communicate the causes of disability among Chilean workers ascribed to the private allowances system, their mortality and to correlate the causes of death with diagnoses. SUBJECTS AND METHODS: We analyzed 13,456 consecutive cases judged between August 1990 and April 1992. Mortality was registered up to 12 months after judgment. RESULTS: Total incapacity was determined in 4,158 cases (30.9%), partial incapacity in 1,340 (9.9%) and minor incapacity in 7,958 (59.1%). Osteoarticular diseases were the main cause of disability in 4,460 patients (33.1%) and 77.8% of patients with malignant tumors were considered as having total incapacity. Mortality was 17% among subjects with total incapacity, 1.5% among those with partial disability and 1% among those with minor disability. The cause of death was related to the main disabling disease in 94% of subjects with total incapacity and 66.6% of those with partial incapacity. CONCLUSIONS: Osteoarticular diseases are the main cause of inability among workers ascribed to a private pension system.

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In this study, a discussion and procedure to eliminate K as a factor of correction in the MINI-MULT 82, is presented. This test was developed in Costa Rica and based on Kincannon's Mini-Mult, a short form of the Minnesota Multiphasic Personality Inventory (MMPI). However, the test has been independent from the MMPI, and it is not used as s predictor form. In consequence, the influence of factor K has been considered, either as a suppressor variable or as a contributor to improve the validity of the test. Two samples, one of non patients and other of psychiatric patients were compared using Student's t-test. To do that, the test was scored first, without the K factor and finally, using that one. The results showed statistical differences between the samples (p < 0.001) and they were stronger when the K factor was not used. This findings support the elimination of K as a factor of correction in the MINI-MULT 82. Implications and guidelines about future research, are discussed at the end.

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In this study, a discussion and procedure to eliminate K as a factor of correction in the MINI-MULT 82, is presented. This test was developed in Costa Rica and based on Kincannons Mini-Mult, a short form of the Minnesota Multiphasic Personality Inventory (MMPI). However, the test has been independent from the MMPI, and it is not used as s predictor form. In consequence, the influence of factor K has been considered, either as a suppressor variable or as a contributor to improve the validity of the test. Two samples, one of non patients and other of psychiatric patients were compared using Students t-test. To do that, the test was scored first, without the K factor and finally, using that one. The results showed statistical differences between the samples (p < 0.001) and they were stronger when the K factor was not used. This findings support the elimination of K as a factor of correction in the MINI-MULT 82. Implications and guidelines about future research, are discussed at the end.

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In this study, a discussion and procedure to eliminate K as a factor of correction in the MINI-MULT 82, is presented. This test was developed in Costa Rica and based on Kincannon’s Mini-Mult, a short form of the Minnesota Multiphasic Personality Inventory (MMPI). However, the test has been independent from the MMPI, and it is not used as s predictor form. In consequence, the influence of factor K has been considered, either as a suppressor variable or as a contributor to improve the validity of the test. Two samples, one of non patients and other of psychiatric patients were compared using Student’s t-test. To do that, the test was scored first, without the K factor and finally, using that one. The results showed statistical differences between the samples (p < 0.001) and they were stronger when the K factor was not used. This findings support the elimination of K as a factor of correction in the MINI-MULT 82. Implications and guidelines about future research, are discussed at the end.

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The correction norms for the Mini-Mult 82 (71 items from Kincannon's MMPI short form, plus 11 representative items from 5(Mf) Scale from the same test--developed by the authors--) are presented. A 1,343 normal, over 15-year-old Costarrican subjects sample was tested. Correction norms were obtained successfully. More reliable scores were obtained by using the Mini-Mult 82 as an independent test (i.e. without MMPI's score predictions). Statistical differences in F, 1(Hs), 2(D), 3(Hy), 4(Pd), 5(Mf) and 8(Sc) scales were found when gender was controlled. "T" scores were computed for raw scores on each scale. Additional research is suggested to improve the test's reliability and validity characteristics.

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