Interfacial Electric Effects on a Non-Isothermal Electroosmotic Flow in a Microcapillary Tube Filled by Two Immiscible Fluids.

In this work, a non-isothermal electroosmotic flow of two immiscible fluids within a uniform microcapillary is theoretically studied. It is considered that there is an annular layer of a non-Newtonian liquid, whose behavior follows the power-law model, adjacent to the inside wall of the capillary, which in turn surrounds an inner flow of a second conducting liquid that is driven by electroosmosis. The inner fluid flow exerts an interfacial force, dragging the annular fluid due to shear and Maxwell stresses at the interface between the two fluids. Because the Joule heating effect may be present in electroosmotic flow (EOF), temperature gradients can appear along the microcapillary, making the viscosity coefficients of both fluids and the electrical conductivity of the inner fluid temperature dependent. The above makes the variables of the flow field in both fluids, velocity, pressure, temperature and electric fields, coupled. An additional complexity of the mathematical model that describes the electroosmotic flow is the nonlinear character due to the rheological behavior of the surrounding fluid. Therefore, based on the lubrication theory approximation, the governing equations are nondimensionalized and simplified, and an asymptotic solution is determined using a regular perturbation technique by considering that the perturbation parameter is associated with changes in the viscosity by temperature effects. The principal results showed that the parameters that notably influence the flow field are the power-law index, an electrokinetic parameter (the ratio between the radius of the microchannel and the Debye length) and the competition between the consistency index of the non-Newtonian fluid and the viscosity of the conducting fluid. Additionally, the heat that is dissipated trough the external surface of the microchannel and the sensitivity of the viscosity to temperature changes play important roles, which modify the flow field.

Epistaxis severas. Nuestra experiencia y revisión de literatura / Severe epistaxis. Our experience and review of literature / Epistaxe grave. A nossa experiência e revisão da literatura

La epistaxis posterior es una de las urgencias más frecuente en la Otorrinolaringología. A pesar de esto no hay lineamientos claros entre los especialistas para su manejo. En este trabajo revisamos nuestra experiencia en 67 pacientes con diagnóstico de epistaxis severa que ingresaron por la guardia del Hospital Universitario ¨José de San Martín¨, entre el período de enero - septiembre de 2014 y comparándola con la literatura mundial con el objetivo de postular un algoritmo de tratamiento de esta enfermedad. A 66 de los 67 pacientes se les realizó taponaje anteroposterior (TAP) con diferentes métodos y 1 de los 67 fue directamente a cirugía endoscó- pica rinosinusal (CERS)...

Posterior epistaxis is one of the most common otolaryngology emergencies. Despite this, there are no clear guidelines among specialists for its management. In this paper, we review our experience in 67 patients with diagnosis of severe epistaxis who were evaluated on the emergency room of the University Hospital Jose de San Martin between January to September 2014. We compared our experience with the world literature in order to apply an algorithm treatment of this disease. 66 of 67 patients underwent posterior nasal packing (PNP)...

A epistaxe posterior é uma das emergências otorrinolaringológicas mais comuns. Apesar disso, não há um claro consenso entre os especialistas sobre seu procedimento. Neste artigo, apresentamos nossa experiência com 67 pacientes com diagnóstico de epistaxe grave atendidos pelo plantão do Hospital Universitário Jose de San Martin entre o período de janeiro a setembro de 2014 e comparamos com a literatura mundial, a fim de determinar um algoritmo de tratamento desta doença. 66 dos 67 casos foram submetidos a tamponamento ântero-posterior (TAP) com diferentes métodos e 1 foi diretamente encaminhado para cirurgia endoscópica rinossinusal (CERS). Destes 67 pacientes, 31 tiveram inicialmente escolhido o TAP como tratamento definitivo e, para os 36 restantes, CERS...

Utilización de factores de crecimiento plaquetarios autólogos en artrodesis lumbares posterolaterales / Utilização de fatores de crescimento plaquetários autólogos em artrodese lombar póstero-lateral / Use of autologous platelet growth factors in posterolateral lumbar spinal fusions

OBJETIVO: Evaluar calidad e índice de pseudoartrosis en la formación del callo óseo en artrodesis instrumentadas lumbares posteriores con injerto óseo autólogo enriquecido con factores de crecimiento plaquetarios (FCP). MÉTODOS: Estudio clínico analítico experimental simple ciego entre Junio de 2007 y Junio de 2009 comparando dos grupos, uno en el que se utilizó FCP en artrodesis lumbares posteriores y otro en el que no se aplicó el factor, evaluando las siguientes variables: índice de pseudoartrosis, formación del callo óseo y complicaciones postoperatorias. RESULTADOS: Se evaluaron 26 pacientes, edad promedio 61,23 años, divididos en dos grupos de 13 pacientes. El grupo en el que se utilizó FCP presentó fusiones radiográficamente sólidas en el 61,54 %, sin registro de pseudoartrosis pero con incidencia de infección y sangrado postoperatorios de 15.39%, mientras que en el grupo sin FCP el 69.23% alcanzó fusiones sólidas con 7.69% de pseudoartrosis sin otras complicaciones relacionadas con la intervención. CONCLUSIÓN: Si bien el grupo con FCP no presentó pseudoartrosis, registró mayor incidencia de complicaciones postoperatorias y menor número de fusiones radiográficamente sólidas. Aunque la cantidad de pacientes no permite obtener resultados estadísticamente significativos el presente puede ser el inicio de un estudio mayor.

OBJETIVO: Avaliar a qualidade e taxa de pseudoartrose em formação de calos em instrumentado fusão lombar com enxerto ósseo autólogo depois enriquecido com fatores de crescimento plaquetário (FCP). MÉTODOS: Analytical experimental tipo cego única clínica entre junho de 2007 e junho de 2009 comparando dois grupos, um que foi usado no FCP após artrodese lombar e outro que não se aplicam, avaliar as seguintes variáveis : taxa de pseudoartrose de formação de calos e as complicações pós-operatórias. RESULTADOS: Foram avaliados 26 pacientes, com idade média de 61,23 anos, divididos em dois grupos de 13 pacientes. O grupo que foi usado FCP apresentou fusões radiograficamente sólidos em 61,54%, sem registro, mas com incidência não-união de infecção e sangramento pós-operatório 15,39%, enquanto que no grupo sem o FCP% 69,23 alcançado fusões sólidas com 7,69% de pseudoartrose sem outras complicações relacionadas com a intervenção. CONCLUSÃO: Apesar de o grupo não se apresentar com FCP não sindicalizados, maior incidência de complicações pós-operatórias e menos fusões radiograficamente sólidos. Embora o número de pacientes que não é possível obter resultados estatisticamente significativos isso pode ser o início de um estudo maior.

OBJECTIVE: To evaluate quality and rate of pseudoarthrosis in callus formation in instrumented posterolateral lumbar fusion with the use of autologous bone graft enriched with platelet growth factors (PGFs). METHODS: A clinical analytical experimental single blind trial was carried out between June 2007 and June 2009 comparing two groups, one in which PGFs were used in lumbar spinal fusions while in the other the PGFs were not applied, to analyze the following variables: rate of pseudoarthrosis, callus formation and postoperative complications. RESULTS: We evaluated 26 patients, mean age 61.23 years, divided in two groups of 13 patients each. The group in which PGFs were used presented radiographically solid fusions at 61.54% with no record of pseudoarthrosis, although with incidence of infection and postoperative bleeding of 15.39%, while in the group without PGFs 69.23% achieved solid fusions presenting a rate of pseudoarthrosis of 7.69% with no other complications related to the intervention. CONCLUSION: Even though the group without PGFs did not present pseudoarthrosis, a higher incidence of postoperative complications and fewer radiographically solid fusions could be observed. Even though the number of patients is not sufficient to obtain statistically significant results, the present analysis may be the beginning of further study.

Antimicrobial effect of polyphenols from apple skins on human bacterial pathogens

Apples possess many beneficial properties for the human health related with their high content in phenolic compounds. The antimicrobial effect of these compounds from the skin of two apple varieties, Royal Gala and Granny Smith, against human pathogens was examined. The phenolic compounds were extracted with the following solvents: A, acetone: water: acetic acid; B, ethyl acetate: methanol: water and C, ethanol: water. Total phenolic, flavonoid and non-flavonoid contents were analyzed in the extracts. The antimicrobial effect was determined using the agar diffusion method. The highest inhibitory effect of both apple varieties corresponded to extract A, which contained a high phenolic content. The Granny Smith extracts with higher phenolic content presented a superior antimicrobial effect against the selected microorganisms: Escherichia coli, Escherichia coli ATCC 25922, Escherichia coli ATCC 35218, Staphylococcus aureus ATCC 25923, Staphylococcus aureus ATCC 29213, Pseudomonas aeruginosa ATCC 27853, Enterococcus faecalis ATCC 29212 and Listeria monocytogenes. The most sensitive microorganisms were Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853and Staphylococcus aureus ATCC 29213, whereas the most resistant strains were Escherichia coli ATCC 35218 and Escherichia coli. The results obtained demonstrate a direct relationship between the phenolic content of the extracts and the antimicrobial effect.