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HYPOTHESIS: The petal effect is a well-known natural phenomenon in surface science and has served as inspiration for the creation of several materials with superhydrophobic qualities and high adhesion. As surface roughness has a crucial role in these properties, being able to modulate it could help us design materials at will. Capillary penetration frustrates diffusion and promotes large contact angles as well as high adhesion. EXPERIMENTS: Polystyrene surfaces were created using the spin-coating technique. By varying the polymer concentration, the surface roughness was modified. To determine the roughness parameters, atomic force microscopy was used. We recorded advancing and receding contact angles using water and glycerol as test liquids to study contact angle hysteresis, the work of adhesion and the apparent surface energy, which was determined with the Chibowski and Perea-Carpio method. For the purpose of elucidating the wetting states, captive bubble experiments were conducted. FINDINGS: Using an easy method, we create polystyrene surfaces with both superhydrophobicity and strong adhesion, where the roughness area factor regulates wetting transitions from Cassie-Baxter to Wenzel. The receding contact angle suggests capillary penetration, which we demonstrate by captive bubble experiments. In addition, a link was found between the surface roughness and apparent surface energy.
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We explored the potential of different nanoparticles (TiO2, CaCO3, and Al2O3), considering their pure form and modified with cinnamon essential oil (CEO). These materials were characterized using various techniques, including FTIR spectroscopy, XRD analysis, TGA, and SEM. The interaction between CEO and nanoparticles changed depending on the nanoparticle type. Al2O3 nanoparticles exhibited the strongest interaction with CEO, increasing their antioxidant capacity by around 40% and their transfer of antimicrobial properties, particularly against Gram-negative bacteria. In contrast, TiO2 and CaCO3 nanoparticles showed limited interaction with CEO, resulting in lower antioxidant capacity and antimicrobial activity. Incorporating pure and CEO-modified nanoparticles into polylactic acid (PLA) films improved their mechanical and thermal properties, which are suitable for applications requiring greater strength. This research highlights the potential of metal oxide nanoparticles to enhance the antimicrobial and antioxidant capabilities of polymers. In addition, incorporating cinnamon essential oil can increase the antioxidant and antimicrobial effectiveness of the metal oxide nanoparticles and improve the mechanical and thermal properties of PLA films. Thus, these PLA films exhibit favorable characteristics for active packaging applications.
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Liquid and surface polarities play an important role in wetting phenomena, and this should still be true if the surface is rough. We analyze the wetting of high-polar and low-polar liquids on rough low-polar surfaces made of polystyrene. The experimental results are analyzed by the surface tension components (STC) and the equation-of-state (EQS) approaches. Both approaches predicted a clear increase of the contact angle (CA) with the surface roughness for high-polar liquids, but they failed for low-polar liquids: STC calculations produce the wrong tendency in the total solid surface energy, and EQS is not able to fit the data for these liquids. These results show that low-polar liquids show little dependence on the roughness of a low-polar surface, while high-polar liquids are very sensitive to it. As a consequence, the calculated CAs are close to experimental values only for the high-polar liquids, while there are great differences for low-polarity liquids. Both STC and EQS approaches are able to describe the apparent CAs on polystyrene rough surfaces by using effective surface and interfacial tensions, but their effectiveness is limited to high-polarity liquids.
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Graphene oxide-gold nanoparticle (AuNPs@GO) hybrids were fabricated in water dispersions of graphene oxide (GO) and Au precursor completely free of stabilizing agents by UV-light irradiation. Gold nanoparticle (AuNP) nucleation, growth, and stabilization mechanisms at the surface of GO are discussed on the basis of UV-Vis, Raman, IR, and X-Ray photo-spectroscopy studies. The analyses of AuNPs@GO hybrids by transmission electron microscopy (TEM), thermogravimetric (TGA) and electrochemical tests show that they exhibit outstanding chemical, thermal and electrochemical stabilities. Thus, AuNPs@GO biosensing platforms were fabricated for surface enhanced Raman spectroscopy (SERS) detection of crystal violet (CV), a SERS standard molecule, and in a different set of experiments, for flavin adenine dinucleotide (FAD), a flavoprotein coenzyme that plays an important role in many oxidoreductase and reversible redox conversions in biochemical reactions. AuNPs@GO hybrids synthesized by using UV light irradiation show exceptional stability and high intensification of the Raman signals showing that they have high potential for use as biomedical probes for the detection, monitoring, and diagnosis of medical diseases.
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Técnicas Biossensoriais/métodos , Ouro/química , Grafite/química , Nanopartículas Metálicas/química , Técnicas Eletroquímicas , Flavina-Adenina Dinucleotídeo/química , Microscopia Eletrônica de Transmissão , Oxirredução , Óxidos/química , Oxirredutases/química , Oxirredutases/metabolismo , Espectroscopia Fotoeletrônica , Espectrofotometria , Termogravimetria , Raios Ultravioleta , Água/químicaRESUMO
El Staphylococcus aureus es uno de los microorganismos de mayor importancia en la asistencia médica, emergente en la comunidad y en el medio hospitalario. El objetivo de este trabajo es presentar una actualización sobre los elementos de interés clínico de la microbiología molecular del Staphylococcus aureus. Para confeccionar esta revisión se utilizaron las bases de datos de Scielo, HINARI, Pubmed-Medline y bibliografías disponibles sobre el tema y los descriptores empleados fueron: Staphylococcus aureus, resistencia a la meticilina, genes, epidemiología molecular, virulencia y la combinación entre ellos. Se revisaron los elementos que determinan sus factores de virulencia, la resistencia antimicrobiana, la versatilidad de estrategias patogénicas, la capacidad de sobrevivir en diferentes condiciones, la evolución y virulencia de los procesos que produce. Igualmente se abordó el diagnóstico de la resistencia, las técnicas de diagnóstico molecular, con sus utilidades, limitaciones, ventajas y desventajas y los estudios de estos temas en los últimos años en Cuba, pues circulan cepas de Staphylococcus aureus resistentes a la meticilina, pero no se conoce la situación real. Se recomienda la conveniencia y necesidad de organizar y armonizar estudios clínicos, epidemiológicos y microbiológicos, que puedan mostrar cuál es la situación actual de este microorganismo y sus infecciones, que aporten datos de su evolución molecular, para evaluar la tendencia de la situación encontrada, que permitan decisiones para el desarrollo de programas de vigilancia y control y revitalicen los medios y métodos de diagnóstico. Resulta importante el conocimiento actualizado del tema, la interpretación de nuevos resultados y el intercambio científico(AU)
Staphylococcus aureus is one of the most important microorganisms in medical care, emerging in the community and in the hospital environment. The objective of this work is to present an update on the elements of clinical interest of the molecular microbiology of Staphylococcus aureus. To make this review, the databases of Scielo, HINARI, Pubmed-Medline and bibliographies available on the subject were used and the descriptors used were: Staphylococcus aureus, methicillin resistance, genes, molecular epidemiology, virulence and the combination between them. We reviewed the elements that determine its virulence factors, antimicrobial resistance, the versatility of pathogenic strategies, the ability to survive in different conditions, the evolution and virulence of the processes it produces. Likewise, the diagnosis of resistance, molecular diagnostic techniques, with their utilities, limitations, advantages and disadvantages, and the studies of these subjects in recent years in Cuba were addressed, since methicillin-resistant strains of Staphylococcus aureus circulate, but not the real situation is known. It is recommended the convenience and need to organize and harmonize clinical, epidemiological and microbiological studies, which can show what is the current situation of this microorganism and its infections, that provide data of its molecular evolution, to evaluate the tendency of the situation found, that allow decisions for the development of surveillance and control programs and revitalize the means and methods of diagnosis. Current knowledge of the subject, interpretation of new results and scientific exchange is important(AU)
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Humanos , Staphylococcus aureus/virologia , Literatura de Revisão como Assunto , Staphylococcus aureus Resistente à Meticilina/imunologia , Estudos Epidemiológicos , Bases de Dados BibliográficasRESUMO
La leptospirosis humana es una enfermedad zoonótica de distribución mundial, con frecuencia subdiagnosticada por presentar un amplio espectro de manifestaciones clínicas. El objetivo es presentar una actualización sobre el diagnóstico de la leptospirosis humana. Se consultó la bibliografía disponible sobre el tema en las bases de datos de Scielo, HINARI, Pubmed-Medline y diferentes textos y artículos en los que se profundizaba en el diagnóstico. Las técnicas microbiológicas son la base de la confirmación de la enfermedad. La observación por microscopía de campo oscuro es poco sensible, ya que las leptospiras se pueden confundir con filamentos proteicos u otros artefactos. El aislamiento del agente etiológico constituye la prueba de oro, aunque ofrece un resultado retrospectivo. La reacción en cadena de la polimerasa es un método útil para el diagnóstico rápido de la infección. El diagnóstico serológico cobra vital importancia en esta entidad, pues supera en rapidez, sencillez y bajo costo al cultivo. La microaglutinación con antígenos vivos es la técnica de referencia. Las pruebas rápidas basadas en la inmunocromatografía de flujo lateral son una variante muy útil, ya que ofrecen el resultado entre 5 y 30 minutos.
The human leptospirosis is zoonotic disease with worldwide distribution, frequently present a difficult diagnosis because have a wide spectrum of clinical manifestations. The objective of this work is to present an upgrade on the diagnosis of the human leptospirosis; for it was consulted it the available bibliography on the topic in the databases of Scielo, HINARI, Pubmed-Medline and different texts and articles of the last five years to deepen in the diagnosis. The microbiologic diagnostic is the base of the confirmation of the illness; it depends on the taking of sample in the appropriate moment and the correct indication of the complementary one according to the clinical phase. The observation for microscopy of dark field is not very sensitive since the leptospiras can made a mistake with poetics filaments or other devices. The etiologic agent's isolation constitutes the gold standard test; although offers a retrospective result. The polymerase chain reaction is a method used for the quick diagnosis of the infection, the quantitative variant in real time shows substantial advantages, because it allows the immediate reading and avoids the electrophoresis step, these techniques are not available for its high cost. The serologic diagnostic charges vital importance in this entity, it overcomes in speed, simplicity and low cost to the cultivation; the microagglutinación with a live antigen is considered the reference technique. The detection of IgM for enzyme linked immunobsorbent assay has been broadly used. The rapid tests based on the lateral flow immunochromatography, are a very useful variant, since they offer the result between 5 and 30 minutes.
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Humanos , Literatura de Revisão como Assunto , Separação Celular/estatística & dados numéricos , Reação em Cadeia da Polimerase/métodos , Leptospirose/diagnósticoRESUMO
Electrostatic interactions, mediated by ionic-exchange, between polyethylenimine (PEI) and glucose oxidase (GOx) were used to form GOx-PEI macro-complex, which were evaluated for pH and thermal stability of GOx. Under the experimental conditions, the complex had a dominant GOx presence on its surface and a hydrodynamic diameter of 205 ± 16 nm. Activity was evaluated from 40 to 75 °C, and at pH from 2 to 12. GOx activity in complex was maintained up to 70 °C and it was lost at 75 °C. In contrast, free GOx showed a maximum activity at 50 °C, which was completely lost at 70 °C. This difference, observed by fluorescence analysis, was associated with the compact unfolded structure of GOx in the complex. This GOx stability was not observed under pH variations, and complex formation was only possible at pH ≥ 5 where enzymatic activity was diminished by the presence of PEI.
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Glucose Oxidase/metabolismo , Polietilenoimina/metabolismo , Eletricidade Estática , Temperatura , Aspergillus/enzimologia , Estabilidade Enzimática , Flavina-Adenina Dinucleotídeo/metabolismo , Concentração de Íons de Hidrogênio , Nefelometria e Turbidimetria , Soluções , Espectrometria de FluorescênciaRESUMO
OBJECTIVE: This study evaluated the hydrophobicity of dentin surfaces that were modified through chemical silanization with octadecyltrichlorosilane (OTS). MATERIAL AND METHODS: An in vitro experimental study was performed using 40 human permanent incisors that were divided into the following two groups: non-silanized and silanized. The specimens were pretreated and chemically modified with OTS. After the chemical modification, the dentin hydrophobicity was examined using a water contact angle measurement (WCA). The effectiveness of the modification of hydrophobicity was verified by the fluid permeability test (FPT). RESULTS AND CONCLUSIONS: Statistically significant differences were found in the values of WCA and FPT between the two groups. After silanization, the hydrophobic intraradicular dentin surface exhibited in vitro properties that limit fluid penetration into the sealed root canal. This chemical treatment is a new approach for improving the sealing of the root canal system.
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Cavidade Pulpar/efeitos dos fármacos , Dentina/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Tratamento do Canal Radicular/métodos , Silanos/química , Infiltração Dentária , Cavidade Pulpar/química , Dentina/química , Permeabilidade da Dentina/efeitos dos fármacos , Humanos , Microscopia Eletrônica de Varredura , Reprodutibilidade dos Testes , Camada de Esfregaço , Propriedades de Superfície/efeitos dos fármacos , Fatores de Tempo , Raiz Dentária/química , Raiz Dentária/efeitos dos fármacosRESUMO
Objective: This study evaluated the hydrophobicity of dentin surfaces that were modified through chemical silanization with octadecyltrichlorosilane (OTS). Material and Methods: An in vitro experimental study was performed using 40 human permanent incisors that were divided into the following two groups: non-silanized and silanized. The specimens were pretreated and chemically modified with OTS. After the chemical modification, the dentin hydrophobicity was examined using a water contact angle measurement (WCA). The effectiveness of the modification of hydrophobicity was verified by the fluid permeability test (FPT). Results and Conclusions: Statistically significant differences were found in the values of WCA and FPT between the two groups. After silanization, the hydrophobic intraradicular dentin surface exhibited in vitro properties that limit fluid penetration into the sealed root canal. This chemical treatment is a new approach for improving the sealing of the root canal system.
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Humanos , Cavidade Pulpar/efeitos dos fármacos , Dentina/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Tratamento do Canal Radicular/métodos , Silanos/química , Infiltração Dentária , Cavidade Pulpar/química , Permeabilidade da Dentina/efeitos dos fármacos , Dentina/química , Microscopia Eletrônica de Varredura , Reprodutibilidade dos Testes , Camada de Esfregaço , Propriedades de Superfície/efeitos dos fármacos , Fatores de Tempo , Raiz Dentária/química , Raiz Dentária/efeitos dos fármacosAssuntos
Masculino , Feminino , Humanos , Idoso , Idoso de 80 Anos ou mais , Geriatria , Idoso , Disseminação de InformaçãoRESUMO
BACKGROUND: Migration is a growing phenomenon with a well-known impact in infectious diseases epidemiology. Currently, immigrants represent almost 10% of the Spanish population. The majority come from countries where the prevalence of chronic viral illnesses is higher than in Spain. METHODS: To describe clinicoepidemiological features of human immunodeficiency virus (HIV)-infected immigrants attending our Unit and to compare differential characteristics depending on geographical origin, information from all new immigrants from January 1997 to December 2006 was collected. STUDY DESIGN: noninterventional retrospective chart review. RESULTS: We screened 1,609 patients of whom 77 (4.8%) were HIV antibody (Ab) positive. Of these, 80% were sub-Saharan Africans (SSAFR) and 20% were South-Central Americans (SCA). HIV prevalence was higher in SSAFR (5.6% vs 3.2%; p= 0.04). Overall, of those who were HIV Ab positive, 70% were male (median age 30 years), 59% heterosexuals, 9% hepatitis C virus coinfected, 8.6% hepatitis B virus coinfected, and 34% showed a positive tuberculin skin test. Median CD4 cell count was 263 cells/microL, median HIV-ribonucleic acid viral load 4.6 Log/mL, and 48% had a late diagnosis [acquired immunodeficiency syndrome (AIDS)-defining illness or <200 CD4 microL at the time of diagnosis]. Only 68% of patients for whom antiretroviral therapy was indicated actually started therapy and 22% were lost to follow-up just after diagnosis. SCA had lower CD4 cell counts (26 vs 168 cells/microL; p= 0.016), higher viral loads (5.3 vs 4.8 Log; p= 0.001), and were more likely to have an AIDS-defining illness (53% vs 21%; p= 0.04) compared to SSAFR. Tuberculin skin test reactivity was more common among SSAFR versus SCA [adjusted by CD4 count, odds ratio (OR) 6.3 and 95% confidence interval (CI): 0.65-60.5]. The main risk factor for late diagnosis was geographical origin: OR 4.6 (95% CI: 1.11-19.3) (SCA vs SSAFR; adjusted by the interval between the date of arrival in Spain and the date of HIV diagnosis). CONCLUSIONS: Almost half the HIV-infected immigrants were diagnosed in late stages. Patients were frequently lost to follow-up, and a significant minority did not start highly active antiretroviral therapy when indicated. SCA seem to have more severe immunosuppression at the time of diagnosis than SSAFR. Early voluntary routine HIV screening should be promoted.
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Emigração e Imigração , Infecções por HIV/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Adulto , África Subsaariana/epidemiologia , Antirretrovirais , América Central/epidemiologia , Emigração e Imigração/estatística & dados numéricos , Feminino , Geografia , Anticorpos Anti-HIV , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Hospitais , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência , Encaminhamento e Consulta , Estudos Retrospectivos , América do Sul/epidemiologia , Espanha/epidemiologia , Medicina Tropical , Carga Viral , Adulto JovemRESUMO
The prevention of nonspecific protein adsorption is a crucial prerequisite for many biomedical and biotechnological applications. Therefore, the design of robust and versatile methods conferring optimal protein-resistance properties to surfaces has become a challenging issue. Here we report the unexpected case of polycation-ending polyelectrolyte multilayers (PEM) that efficiently prevented the adsorption of a negatively charged model protein, glucose oxidase (GOX). PEM films were based on two typical weak poyelectrolytes: poly(allylamine hydrochloride) (PAH) and poly(acrylic acid) (PAA). No chemical modification of the polyelectrolytes was required and tunable GOX adsorption was possible by simply changing the buildup pH conditions. Protein-resistance properties are attributed to high film hydration becoming the predominant factor over electrostatic interactions. We explain this effect by oscillations of the internal PAA ionization state throughout the buildup, which results in an excess of carboxylic acid groups within the film. This excess acts as a reservoir of potential carboxylate groups compensating the outer PAH positive charges. Partial results indicated that the system was also resistant to the adsorption of a positively charged protein, lysozyme. Control of the internal ionization of weak polyelectrolyte multilayers might open a route toward simple tuning of protein adsorption. These results should help to rationalize the design of biomaterials, biosensors, or protein separation devices.
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Eletrólitos/química , Eletrólitos/metabolismo , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Poliaminas/química , Adsorção , Técnicas Eletroquímicas , Concentração de Íons de Hidrogênio , Microscopia de Força Atômica , Polieletrólitos , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de SuperfícieRESUMO
We investigate the pattern formation produced by precipitated species during solvent evaporation through the numerical solution of a set of partial differential equations that account for the mechanisms of evaporation, diffusion, and precipitation. A pattern is formed because solvent evaporation provokes precipitation of species near the border of the system producing ringlike depositions from the edge to the center. Solvent evaporation is modeled as occurs with a liquid drop on a surface. The spacing between rings and its width are constant and roughly constant, respectively. Pattern formation follows the evaporation process inducing trends on pattern formation that are different to those produced by the precipitation of two species in a diffusive front (Liesegang rings). The spatial structure of rings under solvent evaporation is similar to those observed during solvent evaporation on two oppositely charged colloids and is attributable to the competition between precipitation and evaporation processes.
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Liquid cell atomic force microscopy (LC-AFM) is used to image self-assembled polyelectrolyte films eliminating any drying effects on the film structure. Weak/weak and strong/weak polyelectrolyte films are formed by the alternated deposition of poly(acrylic acid) [PAA]/poly(allylamine hydrochloride) [PAH], and poly(sodium 4-styrene sulfonate) [PSS]/PAH, respectively, forming a granular surface structure. Number and area of grains (GN, GA) are used to characterize the surface of these films during their build up process. We show that hydrophilic PAA increases GA and decreases GN, while these parameters follow an opposite behavior with PSS. In both cases, GA and GN always have a simple inverse relationship, and then grain surface coverage (GS=GNGA) is nearly constant and independent of polyelectrolyte nature and the substrates used here, but also in the published data as well. The drying of the weak/weak film was also imaged after natural and forced solvent evaporation, and the surface structure is strongly affected, although the GS values keep roughly the same value found for wet films. The set of these results indicates that GS may be considered as a constant parameter during the build-up for the self-nascent assembled polyelectrolytes. The granular structure is still maintained after glucose oxidase adsorption on these films with comparable GS values.
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Microscopia de Força Atômica/métodos , Poliaminas/química , Poliestirenos/químicaRESUMO
Brownian dynamics simulations were performed to study the structure of polyelectrolyte complexes formed by two flexible, oppositely charged polyelectrolyte chains. The distribution of monomers in the complex as well as the radius of gyration and structure factor of complexes and individual polyelectrolytes are reported. These structural properties were calculated for polyelectrolyte chains with equal number of monomers, keeping constant the bond length of the negative chain and increasing the bond length of the positive chain. This introduces an asymmetry in the length of the chains that modulates the final structure of the complexes. In the symmetric case the distribution of positive and negative monomers in the complex are identical, producing clusters that are locally and globally neutral. Deviations from the symmetric case lead to nonuniform, asymmetric monomer distributions, producing net charge oscillations inside the complex and large changes in the radius of gyration of the complex and individual chains. From the radius of gyration of the polyelectrolyte chains it is shown that the positive chain is much more folded than the negative chain when the chains are asymmetric, which is also confirmed through the scaling behavior of the structure factors.
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The translational and rotational motions of optically anisotropic spherical particles embedded in cross-linked polyacrylamide gels is studied by dynamic light scattering. The particles are liquid crystal droplets solidified in the nematic phase. The amount of cross linkers is varied to cross the sol-gel transition where the system becomes nonergodic for both translational and rotational diffusion modes of the probes. The translational and rotational dynamic correlation functions are obtained by measuring the intensity correlation function between crossed polarizers in the parallel and perpendicular geometries. Data from nonergodic systems is analyzed using an extension, to include rotations, of the method of Pusey and van Megen [Physica A 157, 705 (1989)]. Both diffusion modes are observed to be arrested as the rigidity of the gel increases.
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Inicialmente se concibio el proyecto para una demanda en la estacion nueva de 80 MMPCD para el cual se desarrollo la Ingenieria de Detalle y el presupuesto general. Posteriormente se ajustaron los volumenes a las demandas finales entre Guaracachi, Transredes y Chaco para el cual se elaboro otro proyecto completo. Sin embargo debido a limitaciones de cortes para interconectar la nueva y antigua estacion se concibe un nuevo proyecto, en el cual Prosertec elabora planos, lista de materiales y toda la ingenieria por fases. Este proyecto es el que se presenta en el presente documento. Se concibio el proyecto en cuatro fases claramente definidas, debido a que para realizar algunos trabajos se debio interrumpir el suministro de gas natural, lo cual significaba una parada en las ocho turbinas de generacion lo que ocasionaba interrumpir el suministro de Energia Electrica a la ciudad de Santa Cruz. Fase 1 y 2: Comprende el primer paro, con una interrupcion del suministro de gas por diez horas para ejecutar la interconexion programado para el 7 de marzo y habilitar el suministro a la estacion nueva hasta el 15 de marzo. Fase 3: Comprende la instalacion del ramal de medicion y el ramal de regulacion a la estacion nueva se concluyo el 14 de abril de 1999. Fase4: Comprende el traslado e instalacion de los dos ramales de regulacion y ramal de medicion de la estacion antigua a la nueva localizacion. Para lo cual se interrumpira el suministro de gas a esta estacion, pero la demanda de energia electrica sera abastecida por la estacion nueva. Se completo esta fase para el 20 de julio. Concluyendo el proyecto el 25 de agosto.
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Presentar las ventajas de la técnica de interposición gástrica transhiatal en pacientes con estenosis esofágica severa. Es un estudio prospectivo, descriptivo, realizado a tres pacientes con disfagia, sialorrea y desnutrición grave por estenosis esofágica severa. Dos por ingesta de cáustico y el otro por traumatismo cervical. Luego de la esofagectomía, el reemplazo se hizo mediante interposición de un tubo gástrico con sección de píloro, preservando la vascularización. lo cual incrementa en unos 5 cm la longitud, el mismo se ascendió por vía transhiatal, con anastomosis cervical. Servicio de Cirugía III. Hospital Vargas de Caracas. Venezuela 1995-1998. La técnica fue de fácil aplicación. En todos los casos la complicación presentada fue la estenosis de la anastomosis cervical, resueltas con dilataciones endoscópicas, en promedio 11.6 sesiones. Todos los pacientes toleran la vía oral, ninguno presentó fístulas, niegan síntomas y el índice de masa corporal del grupo se incrementó en 3,1 kg/m². La esofagectomía e interposición gástrica transhiatal, es una cirugía técnicamente viable, aplicable a todo tipo de paciente, con estenosis esofágica severa; con la sección del píloro y liberación del duodeno, se logra incrementar la longitud del tubo gástrico y permitir una anastomosis cervical sin tensión, lo cual evita; la aparición de fístulas. Los resultados desde el punto de vista funcional son óptimos ya que restablece la ingesta de todo tipo de alimento, con mejoría del estado nutricional del paciente, con mínimo de complicaciones
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Humanos , Masculino , Feminino , Adulto , Esofagectomia , Constrição Patológica , Venezuela , Cirurgia GeralRESUMO
Hoy día la obesidad mórbida constituye un severo problema de salud pública y es la forma de malnutrición más frecuente en Estados Unidos afectando a 12 millones de norteamericanos. Se considera que una persona es morbiobesa cuando su índice de masa corporal (IMC) excede de 35. Son muchas las complicaciones asociadas a esta enfermedad entre las que incluyen HTA, diabetes, cardiopatía isquémica, artropatías, neumopatías, etc. La cirugía sigue siendo el tratamiento de primera línea para estos pacientes. Se presentan 7 casos de pacientes con obesidad mórbida con IMC entre 39.42 y 65.30 a quienes se les realizó bypass gástrico con modificaciones a la técnica tradicional. Se busca con ello evitar los inconvenientes de este tipo de cirugía como lo son la disrupción de la línea de grapas, la dilatación de la anastomosis gastroyeyunal y lograr un adecuado y duradero régimen de pérdida de peso. No hubo muertes intraoperatorias ni postoperatorias. Las únicas complicaciones fueron en el postoperatorio y fue un caso de seroma y otro de infección de la herida operatoria. Luego de un seguimiento de entre 3 y 5 meses, los pacientes han experimentado un porcentaje de exceso de peso perdido promedio de 50 por ciento. Concluimos que esta técnica constituye una buena alternativa para el tratamiento de la morbiobesidad. Ha transcurrido poco tiempo desde que se intervinieron a los pacientes lo que no permite determinar aún sus resultados a largo plazo
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Humanos , Masculino , Adulto , Feminino , Abdome , Obesidade Mórbida/cirurgia , Obesidade Mórbida/diagnóstico , Obesidade Mórbida/mortalidade , Gastroenterologia , Saúde Pública , VenezuelaRESUMO
En los últimos años la enfermedad adherencial de los anexos se ha incrementado debido principalmente al aumento en la frecuencia de infecciones pélvicas lo que origina, de acuerdo con la localización, naturaleza y extensión de las lesiones, problemas de esterilidad. En este trabajo se informan los resultados obtenidos en 70 pacientes con esta enfermedad en las que se realizó salpingo-ovariolisis microquirúrgica con el propósito de corregir su esterilidad. Todas las pacientes recibieron rutinariamente medidas adyuvantes en el pre, trans y posoperatorio inmediato (heparina, corticoides y antimicrobianos). El tiempo mínimo de observación posoperatoria fue de seis meses. En 27 de las 70 enfermas (38.6 por ciento) las adherencias eran laxas (IA y IIA de Hulka), en tanto que en 43 (61.4 por ciento) estas adherencias eran densas y vascularizadas (IB y IIB de Hulka). En el primer grupo se obtuvieron 15 embarazos (20.9 por ciento), cinco de término y cuatro abortos