Outcomes in patients managed with endovascular stent for malignant superior vena cava syndrome.

Background: Malignant Superior Vena Cava Syndrome (SVCS) corresponds to the clinical manifestations due to the restriction of venous return to the right atrium secondary to obstruction of the superior vena cava and/or its main tributaries for a tumor. Endovascular management has proven to be safe, effective and cause a fast symptomatic relief in patients with SVCS. There is limited evidence in factors associated with outcomes in malignant setting for this procedure. Materials and methods: An analytical retrospective study was conducted and included patients that underwent endovascular management for malignant SVCS at the National Cancer Institute of Colombia between May 2016 and May 2021. Clinical and technical variables were analyzed to found associations with outcomes in these patients. Results: 54 patients were analyzed. Successful procedure rate was 94.4 %. At 10 months, the OS of the entire cohort of patients was 25 %. Patients with breast or lung cancer (P = 0.031), unsuccessful procedure (P = 0.011), and also with short time of symptoms to the date of the endovascular procedure (P = 0.027) had worse OS. Multivariate analysis showed that lung cancer [HR = 2.55, 95%IC:(1.21-5.36)] and left internal jugular vein or left Innominate vein distal stent attachment [HR = 3.27, 95%IC:(1.31-8.15)] were independent factors for worst OS. Conclusions: Based in the high success rate of the endovascular management and the better outcome in patients with early and successful procedure, this procedure should be considered as part of the multimodal treatment in patients with SVCS independent of the clinical scenario and the oncological diagnosis.

Multidisciplinary management of giant cervicothoracic cutaneous squamous cell carcinoma.

INTRODUCTION: Cutaneus squamous cell carcinoma (SCC) is the second most common type of nonmelanoma skin cancer. SCC is a malignant neoplasm of the skin characterized by aberrant proliferation of keratinocytes. PRESENTATION CASE: We report multidisciplinary surgical management of a 36-year-old male who presented with a huge cutaneous protruding tumor of the cervicothoracic wall. Clinically, he presented with a growing mass on the anterior cervicothoracic wall 3 years ago. Microscopic examination revealed SCC. He underwent complete excision of the lesion. The patient neglected attending our oncological department for receiving chemotherapy. Today, one year after surgery, he is alive without evidence of disease recurrence. DISCUSSION: SCC treatment depends on location of the lesion, involvement of neighboring structures, functional level of the patient, and the patient's acceptance of the proposed management strategy. CONCLUSION: We conclude that SCC can grow to a huge size if left untreated. Surgery by a multidisciplinary surgical team is the primary mode of treatment, followed by chemotherapy if necessary.

Cell cycle inhibition preserves endothelial function in genetically engineered rabbit vein grafts.

We have recently shown that ex vivo gene therapy of rabbit autologous vein grafts with antisense oligodeoxynucleotides (AS ODN) blocking cell cycle regulatory gene expression inhibits not only neointimal hyperplasia, but also diet-induced, accelerated graft atherosclerosis. We observed that these grafts remained free of macrophage invasion and foam cell deposition. Since endothelial dysfunction plays an important role in vascular disease, the current study examined the effect of this genetic engineering strategy on graft endothelial function and its potential relationship to the engineered vessels' resistance to atherosclerosis. Rabbit vein grafts transfected with AS ODN against proliferating cell nuclear antigen (PCNA) and cell division cycle 2 (cdc2) kinase elaborated significantly more nitric oxide and exhibited greater vasorelaxation to both calcium ionophore and acetylcholine than did untreated or control ODN-treated grafts. This preservation of endothelial function was associated with a reduction in superoxide radical generation, vascular cell adhesion molecule-1 (VCAM-1) expression, and monocyte binding activity in grafts in both normal and hypercholesterolemic rabbits. Our data demonstrate that AS ODN arrest of vascular cell cycle progression results in the preservation of normal endothelial phenotype and function, thereby influencing the biology of the vessel wall towards a reduction of its susceptibility to occlusive disease.

First evidence of transmission of Leishmania (Viannia) lainsoni in a Sub Andean region of Bolivia.

Using ubiquitous primers which amplify the variable parts of kDNA minicircle of all Leishmania spp, we obtained for Leishmania (viannia) lainsoni a major band of 605 bp (band 1) shared with L. V. braziliensis and a minor 524 bp band (band 2) specific of L. V. lainsoni. The specificity of the two bands was examined through Southern blot hybridization of kDNA PCR obtained from reference strains belonging to L. braziliensis, L. mexicana, L. donovani complexes with L. V. lainsoni species. Band 1 was not specific of L. V. lainsoni since it hybridized with some isolates belonging to L. braziliensis complex. In contrast, band 2 was L. V. lainsoni specific. PCR-based detection followed by hybridization with the new L. V. lainsoni probe (Band 2) and L. V. braziliensis probe (564 bp), was assayed using sample from a pool of 25 females of Lutzomiya nuneztovari anglesi, blood, skin and liver samples of 18 mammals, spinal cords of four mammals and blood and cutaneous ulcers aspirates from 95 patents from Sub Andean region of La Paz, Bolivia. We observed a ositive hybridization of four patients lesions and the pool of L. nuneztovari anglesi with the L. V. lainsoni probe. It is the first time that L. V. lainsoni is observed in a cycle of transmission in Bolivia. PCR products of three patients lesions and the pool of L. nuneztovari anglesi were also hybridized with the specific probe of L. V. braziliensis suggesting mixed infection in this focus.

Polymerase chain reaction-based identification of New World Leishmania species complexes by specific kDNA probes.

Here we define a new approach for the detection and characterisation of Leishmania complexes by polymerase chain reaction (PCR) and specific hybridisation. The first step consists of PCR amplification of kDNA minicircles using general kinetoplastid primers, which generate a polymorphic multi-banding pattern for all Leishmania species and other Kinetoplastidae. The second step is the identification of the Leishmania species complexes by hybridisation of the PCR products with specific kDNA probes. Polymorphic PCR-products from a genetically diverse set of Leishmania species were analysed by electrophoresis and the banding patterns compared with multi-locus enzyme electrophoresis (MLEE) data. The banding patterns produced by Leishmania species were very heterogeneous, making kDNA-PCR useful for determining closely related strains and for fingerprinting individual strains. The degree of kDNA-PCR and MLEE polymorphism was compared using UPGMA dendrograms. Three complex-specific probes were generated from major PCR bands of reference stocks belonging to the Leishmania mexicana, Leishmania donovani and Leishmania braziliensis complexes, and hybridisation of these probes to membrane-bound PCR products could reliably identify the strain to a complex level. A combination of kDNA-PCR fingerprinting and hybridisation with kDNA probes was found to be useful for both sensitive detection and direct identification of Leishmania species complexes.

Parasitosis intestinales en Altragracia de la Montaña, Estado Miranda, Venezuela: Influencia del programa para la eliminación de oncocercosis / Intestinal parasites in Altragracia de la Montaña, Miranda State, Venezuela: Influence of the program for onchocerciasis elimination

El objetivo general de este trabajo fue determinar la prevalencia de parasitosis intestinales y sus características epidemiológicas en cuatro comunidades de la parroquia Altagracia de la Montaña, Estado Miranda (Venezuela). Se desarrolló un estudio de corte transversal con una muestra constituida por 492 en su mayoría niños, en febrero de 2011. Previo consentimiento informado, se realizó una encuesta clínico-epidemiológica, extracción de sangre y exámenes coproparasitológicos con los métodos directo, Kato y cultivo en agar. El 60% de la población tenía al menos un parásito de transmisión hídrica y/o alimentos contaminados por heces de humanos y/o animales. La elevada frecuencia de protozoarios intestinales, especialmente Blastocystis sp., con predominio entre quienes viven con fallas en la disposición de excretas y baja calidad del agua para consumo humano, demuestran la persistencia de parasitosis intestinales como problema de salud pública; sin embargo, la influencia indirecta de la administración semestral de ivermectina y educación sanitaria con visión etnográfica impartida por el Programa para la Eliminación de Oncocercosis en Bucarito, una de las comunidades evaluadas, tuvo como efecto colateral no sólo disminuir la prevalencia de helmintos intestinales, sino de los protozoarios, a pesar de estar sometida a los mismos factores de riesgo que las comunidades restantes.

The aim of this study was to determine the prevalence of intestinal parasites and their epidemiological characteristics in four rural communities from Altagracia de la Montaña, Miranda State (Venezuela). A cross sectional study was conducted in February 2011 where 492 subjects were evaluated, mostly children. Informed consent was previously obtained. A clinical and epidemiological survey was done. Patients voluntarily brought a fresh stool sample for analysis with direct smear, Kato and agar culture; blood was extracted for eosinophil count. 60% of the evaluated people had at least one parasite transmitted by water or food contaminated by human or animal feces. The high prevalence of protozoa, specially Blastocystis sp., among those who live under poor living conditions such as inadequate feces disposal and low quality of drinking water, shows the persistence of intestinal parasites as a public health problem; nevertheless, indirect influence of ivermectin treatment every six months and health education with an ethnographic orientation given by the Onchocerciasis Elimination Programme in Bucarito, one of the evaluated communities, had an unexpected outcome not only diminishing the prevalence of helminthes but also the prevalence of intestinal protozoa, being this community under the same risk factors as the rest of the evaluated communities.

DISEÑO DE UNA PLATAFORMA INTEROPERABLE PARA UN OBSERVATORIO DE HÁBITOS Y ESTILOS DE VIDA SALUDABLE / DESIGN OF A INTEROPERABLE OBSERVATORY PLATFORM FOR HABITS ANDHEALTHY LIFESTYLES / CONCEPÇÃO DE UMA PLATAFORMA INTEROPERÁVEL PARA UM OBSERVATÓRIO HÁBITOS E ESTILOS DE VIDA SAUDÁVEIS

Esta investigación muestra el diseño de una plataforma interoperable que hace uso del estándar HL7 (Health Level Seven) y permite el registro y análisis de datos relacionados con estilos de vida saludable y prácticas de actividad física en adultos y adultos mayores de las zonas rurales de Colombia. El proyecto se centra en la utilización de las TIC para generar un sistema interoperable que permita la consolidación de los datos, con el fin de facilitar cifras epidemiológicas, hacer diagnósticos que permitan generar estrategias de promoción de la salud y prevención de la enfermedad en las que se promueva la actividad física; y consolidar un marco de referencia para las entidades interesadas. Esta plataforma provee un servicio de integración que puede ser utilizado por entidades externas, compartiendo así información relacionada con hábitos y estilos de vida saludables. Dicha plataforma, utiliza tecnología web ASP.net, con un modelo arquitectural MVC (Modelo Vista Controlador), lenguaje C#, un motor de base de datos SQLServer y servicios web a nivel de integración que usa HL7 como estándar de intercambio de mensajes. Se generó una prueba de control realizada en el año 2014, en ocho municipios del departamento de Cundinamarca en los cuales se aplicaron 304 instrumentos, con los cuales se alimentó la plataforma.

This research shows the design of an interoperable platform that uses the HL7 standard (Health Level Seven) and allows the record and analysis of data related to healthy lifestyles and practices of physical activity in adults and older adults in rural areas of Colombia. The project focuses on the use of ICT to generate an interoperable system that allows the consolidation of data, in order to facilitate epidemiological records, make diagnoses that generate strategies for health promotion and disease prevention in which promote physical activity; and build a framework for stakeholders. This platform provides an integration service that can be used by external entities, to reporting information related to habits and healthy lifestyles. This platform uses web ASP.net technology with architectural model MVC (Model View Controller), C # language, a database SQLServer motor and web services to integration with HL7 standard for the exchange of information. Was performed a control test in to 2014, in eight municipalities of the department of Cundinamarca in which 304 instruments were applied to upload to the platform.

Esta pesquisa mostra o desenho de uma plataforma interoperável que usa o HL7 (Health Level Seven) padrão e permite a gravação e análise de dados relacionados com os estilos de vida saudáveis e prática de atividade física em adultos e idosos nas zonas rurais da Colômbia. O projecto centra-se na utilização das TIC para gerar um sistema de interoperabilidade que permite a consolidação de dados, a fim de facilitar números epidemiológicos, fazer diagnósticos que podem gerar estratégias para promover a saúde e prevenção de doença em que promoção da atividade física; e construir uma estrutura para as partes interessadas. Esta plataforma fornece um serviço de integração que pode ser usado por entidades externas, a partilha de informações relacionadas a hábitos e estilos de vida saudáveis. Esta plataforma, utilizando a tecnologia web ASP.net com um padrão de arquitetura MVC (Model View Controller), a linguagem C#, banco de dados SQLServer do motor e nível de integração de serviços web usando a troca de mensagens HL7 padrão. Um teste de controle realizado em 2014, em oito municípios de Cundinamarca em que foram aplicados 304 instrumentos, com os quais a plataforma foi alimentado foi gerado.

Nitric oxide regulates monocyte chemotactic protein-1.

BACKGROUND: Monocyte chemotactic protein-1 (MCP-1) is a 76-amino-acid chemokine thought to be the major chemotactic factor for monocytes. We and others have demonstrated that NO inhibits monocyte-endothelial cell interactions and atherogenesis. We hypothesize that the antiatherogenic effect of NO may be due in part to its inhibition of MCP-1 expression. METHODS AND RESULTS: Smooth muscle cells (SMCs) were isolated from normal rabbit aortas by the explant method. Cells were then exposed to LPS (10 microg/mL), native LDL, or oxidized LDL (30 microg/mL) for 6 hours. The expression of MCP-1 in SMCs and chemotactic activity in the conditioned medium were induced by lipopolysaccharide (LPS) or by oxidized LDL but not native LDL. The induction of MCP-1 by cytokines or oxidized lipoproteins was associated with an increased generation of superoxide anion by the SMCs and increased activity of the transcriptional protein nuclear factor-kappaB (NFkappaB). The induced expression of MCP-1 and activation of NFkappaB were reduced by previous exposure of the SMCs to the NO donor DETA-NONOate (100 micromol/L) (P<.05). To determine whether NO exerted its effect at a transcriptional level, SMCs and COS cells were transfected with a 400-bp fragment of the MCP-1 promoter. Promoter activity was enhanced by oxidized LDL, and LPS was inhibited by DETA-NO. Nuclear run-on assays confirmed that the effect of NO occurred at a transcriptional level. To investigate the role of endogenous NO in the regulation of MCP-1 in vivo, New Zealand White rabbits were fed normal chow, normal chow plus nitro-L-arginine (LNA), high-cholesterol diet (Chol), or high-cholesterol diet supplemented with L-arginine (Arg). After 2 weeks, thoracic aortas were harvested and total RNA was isolated. Northern analysis using full-length MCP-1 cDNA demonstrated increased expression in Chol and LNA aortas; this expression was decreased in aortas from Arg animals. CONCLUSIONS: These studies indicate that the antiatherogenic effect of NO may be mediated in part by its inhibition of MCP-1 expression.

Fluid flow inhibits endothelial adhesiveness. Nitric oxide and transcriptional regulation of VCAM-1.

BACKGROUND: In the arterial tree, regions exposed to reduced shear stress (low and/or disturbed flow) are predisposed to atherogenesis. Fluid flow is a potent stimulus for the release of endothelium-derived nitric oxide (NO). Because NO inhibits monocyte-endothelial cell interaction, we speculated that the effects of flow in inhibiting atherogenesis might be mediated in part by NO. METHODS AND RESULTS: Confluent monolayers of human aortic endothelial cells were exposed to static or fluid flow conditions for 4 hours. The medium was replaced, and cells were then incubated with native LDL (50 micrograms/mL), oxidized LDL (30 micrograms/mL), or lipopolysaccharide (LPS) (10 ng/mL)+tumor necrosis factor-alpha (TNF-alpha) (10 U/mL) for an additional 4 hours. Functional binding assays using THP-1 monocytes were then performed. Superoxide production by human aortic endothelial cells was monitored by lucigenin chemiluminescence, and expression of the adhesion molecules vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 were quantified by flow cytometry. Whereas native LDL had little effect, incubation with either oxidized LDL or LPS/TNF-alpha significantly increased superoxide production, nuclear factor-kappa B activity, VCAM-1 expression, and endothelial adhesiveness for monocytes. Previous exposure to fluid flow inhibited these sequelae of exposure to cytokines or oxidized lipoprotein. The effect of fluid flow appears to be due in part to shear-induced release of NO, because coincubation with nitro-L-arginine completely abolished these effects of flow. Furthermore, the NO donor PAPA-NONO-ate and 8-Br-cGMP (but not 8-Br-cAMP) mimicked the effects of flow. CONCLUSIONS: Previous exposure to fluid flow decreased cytokine- or lipoprotein-stimulated endothelial cell superoxide production, VCAM-1 expression, and monocyte binding; the effects of flow appear to be due to NO. Flow-mediated NO-dependent regulation of oxidant-responsive transcription may influence the site of a lesion.

Regression or progression. Dependency on vascular nitric oxide.

We have shown that chronic administration of the nitric oxide (NO) precursor L-arginine inhibits atherogenesis in the hypercholesterolemic rabbit. However, the effect of supplemental arginine on preexisting lesions is not known and was the focus of the present study. New Zealand White rabbits received normal chow or 0.5% cholesterol chow for 10 weeks. Subsequently, L-arginine (2.25% in drinking water; ARG group) or vehicle (CHOL group) was administered for an additional 13 weeks, while the high-cholesterol diet was continued. Thoracic aortae were harvested at weeks 10, 14, 18, or 23. Rings of aorta were used to assess NO-dependent vasodilation to acetylcholine. Maximal relaxation to acetylcholine in the CHOL rabbits became progressively attenuated from 53.4% (at week 10) to 17.4% (by week 23). Planimetry of the luminal surface of the aortae from CHOL animals revealed a progressive increase in lesion surface area from 30.3% (at week 10) to 56.5% (by week 23). By contrast, animals in the ARG groups manifested improved endothelium-dependent relaxation associated with a reduction of lesion surface area at 14 and 18 weeks. The arginine-induced improvement in endothelium-dependent relaxation was associated with an increased generation of vascular NO and a reduced generation of vascular superoxide anion. By 23 weeks, 3 of 7 ARG animals had persistent improvement in NO-dependent vasodilation and exhibited a further reduction of lesion surface area tc 5.4%. We conclude that hypercholesterolemia induces a progressive loss of NO-dependent vasodilation associated with progressive intimal lesion formation. Administration of L-arginine to animals with preexisting intimal lesions augments vascular NO elaboration, reduces superoxide anion generation, and is associated with a reduction in lesion surface area. This is the first demonstration that restoration of NO activity can induce regression of preexisting intimal lesions and provides evidence that L-arginine therapy may be of potential clinical benefit.

Interaction of diabetes and hypertension on determinants of endothelial adhesiveness.

Epidemiological studies have established that diabetes mellitus and hypertension are independent risk factors for atherosclerosis. One of the earliest abnormalities seen in atherogenesis is enhanced monocyte adherence to the endothelium. The mechanisms by which diabetes mellitus or hypertension enhances monocyte-endothelial cell interactions are incompletely characterized. It is not known whether there are additive interactions between these risk factors on endothelial adhesiveness for monocytes. Male Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats were fed a normal or fructose-enriched diet. In some cases, animals were injected with streptozotocin (35 mg/kg body weight) to induce diabetes. After 2 weeks, plasma was drawn for biochemical measurements, and thoracic aortas were harvested, opened longitudinally, and exposed to fluorescently labeled mouse monocytoid cells (WEHI 78/24, 2 x 10(6)/mL) for 30 minutes on a rocking platform. Adherent cells were counted by epifluorescence microscopy. WEHI 78/24 binding to aortic segments from SHR animals was elevated compared with segments from WKYs. Fructose feeding alone had no effect on endothelial adhesiveness. When WKYs were made hyperglycemic by STZ injection, monocyte binding was 160% of the control value. Elevated monocyte binding was also observed in aortas derived from SHR animals injected with STZ, indicating an additive effect of hypertension and hyperglycemia. To determine whether alterations in oxidative state played a role in the endothelial adhesiveness, aortic segments were exposed to lucigenin (250 micromol/L) for measurement of superoxide anion. Aortic segments from SHR elaborated 120% more superoxide anion than did controls. Elevated free-radical production was also observed in aortas from diabetic WKYs. Furthermore, thoracic aortas derived from diabetic SHR animals elaborated more superoxide anion than did any of the other groups (374%, P<0.05). Immunohistochemical staining for monocyte chemotactic protein-1 demonstrated increased expression in aortas isolated from diabetic WKY and SHR compared with control vessels. These studies demonstrate that both diabetes and hypertension lead to increased monocyte adherence to the endothelium. This abnormality is associated with increased vascular superoxide production and monocyte chemotactic protein-1 expression. Furthermore, there appears to be an additive interaction between hyperglycemia and hypertension in their effects on endothelial adhesiveness and its determinants.

Human mixed infections of Leishmania spp. and Leishmania-Trypanosoma cruzi in a sub Andean Bolivian area: identification by polymerase chain reaction/hybridization and isoenzyme.

Parasites belonging to Leishmania braziliensis, Leishmania donovani, Leishmania mexicana complexes and Trypanosoma cruzi (clones 20 and 39) were searched in blood, lesions and strains collected from 28 patients with active cutaneous leishmaniasis and one patient with visceral leishmaniasis. PCR-hybridization with specific probes of Leishmania complexes (L. braziliensis, L. donovani and L. mexicana) and T. cruzi clones was applied to the different DNA samples. Over 29 patients, 8 (27.6%) presented a mixed infection Leishmania complex species, 17 (58.6%) a mixed infection Leishmania-T. cruzi, and 4 (13.8%) a multi Leishmania-T. cruzi infection. Several patients were infected by the two Bolivian major clones 20 and 39 of T. cruzi (44.8%). The L. braziliensis complex was more frequently detected in lesions than in blood and a reverse result was observed for L. mexicana complex. The polymerase chain reaction-hybridization design offers new arguments supporting the idea of an underestimated rate of visceral leishmanisis in Bolivia. Parasites were isolated by culture from the blood of two patients and lesions of 10 patients. The UPGMA (unweighted pair-group method with arithmetic averages) dendrogram computed from Jaccard's distances obtained from 11 isoenzyme loci data confirmed the presence of the three Leishmania complexes and undoubtedly identified human infections by L. (V.) braziliensis, L. (L.) chagasi and L. (L.) mexicana species. Additional evidence of parasite mixtures was visualized through mixed isoenzyme profiles, L. (V.) braziliensis-L. (L.) mexicana and Leishmania spp.-T. cruzi. The epidemiological profile in the studied area appeared more complex than currently known. This is the first report of parasitological evidence of Bolivian patients with trypanosomatidae multi infections and consequences on the diseases' control and patient treatments are discussed.

Trasplante pulmonar / Lung transplantation

El trasplante de organos se convirtio en una realidad en 1976 con la aparicion de la ciclosporina como agente inmunosupresor (1). En 1981 Reitz. y col, en Stanford, llevaron a cabo con exito el primer trasplante de corazón y pulmon (2). En 1983, despues de varios años de investigacion clinica durante la decada de los setenta, el grupo de la Universidad de Toronto llevo a cabo exitosamente el primer trasplante pulmonar aislado (3). Tres años más tarde, Yacoub y col, en Inglaterra, realizaron el primer trasplante bilateral en bloque, seguidos por el grupo de Toronto (4). Desde entonces el trasplante pulmonar aislado, uni o bilateral, se ha venido utilizando para el tratamiento de algunos casos seleccionados de enfermedades terminales del pulmon (5). No obstante los grandes avances obtenidos, el progreso del trasplante pulmonar durante los años siguientes se vio amenazado por la presencia de complicaciones como la dehiscencia de la anastomosis bronquial, la infeccion y el rechazo. Los grandes adelantos producidos en el curso de la ultima decada se han traducido en criterios más adecuados de seleccion de donante y receptor, refinamiento de las tecnicas quirurgicas, mejores esquemas de inmunosupresion y disponibilidad de nuevos antibióticos, lo que ha permitido que el trasplante pulmonar sea ahora una opcion terapeutica real, asociada con un incremento de la sobrevida y de la funcion pulmonar. Sin embargo, la aparicion de rechazo crónico en forma de bronquiolitis obliterante constituye hoy dia el factor limitante más significativo y la causa más importante de mortalidad tardia. En la actualidad se consideran básicamente tres modalidades de trasplante pulmonar: unilateral, bilateral y de corazón pulmon.

Human mixed infections of Leishmania spp. and Leishmania-Trypanosoma cruzi in a sub Andean Bolivian area: identification by polymerase chain reaction/hybridization and isoenzyme

Parasites belonging to Leishmania braziliensis, Leishmania donovani, Leishmania mexicana complexes and Trypanosoma cruzi (clones 20 and 39) were searched in blood, lesions and strains collected from 28 patients with active cutaneous leishmaniasis and one patient with visceral leishmaniasis. PCR-hybridization with specific probes of Leishmania complexes (L. braziliensis, L. donovani and L. mexicana) and T. cruzi clones was applied to the different DNA samples. Over 29 patients, 8 (27.6 percent) presented a mixed infection Leishmania complex species, 17 (58.6 percent) a mixed infection Leishmania-T. cruzi, and 4 (13.8 percent) a multi Leishmania-T. cruzi infection. Several patients were infected by the two Bolivian major clones 20 and 39 of T. cruzi (44.8 percent). The L. braziliensis complex was more frequently detected in lesions than in blood and a reverse result was observed for L. mexicana complex. The polymerase chain reaction-hybridization design offers new arguments supporting the idea of an underestimated rate of visceral leishmanisis in Bolivia. Parasites were isolated by culture from the blood of two patients and lesions of 10 patients. The UPGMA (unweighted pair-group method with arithmetic averages) dendrogram computed from Jaccard's distances obtained from 11 isoenzyme loci data confirmed the presence of the three Leishmania complexes and undoubtedly identified human infections by L. (V.) braziliensis, L. (L.) chagasi and L. (L.) mexicana species. Additional evidence of parasite mixtures was visualized through mixed isoenzyme profiles, L. (V.) braziliensis-L. (L.) mexicana and Leishmania spp.-T. cruzi.The epidemiological profile in the studied area appeared more complex than currently known. This is the first report of parasitological evidence of Bolivian patients with trypanosomatidae multi infections and consequences on the diseases' control and patient treatments are discussed

Fosfolipasas A2 y su importancia clínica / Phospholipases A2 and clinical importance

Se revisa el estado actual del conocimiento con respecto al papel fisiológico de las fosfolipasas A2, su clasificación funcional y molecular. Las PLA2 son enzimas que hidrolizan los ácidos grasos de membrana y llevan a la producción de derivados del ácido araquidónico entre otros. Se describen una serie de procesos patológicos en los cuales se encuentran involucradas. De otra parte se presentan los inhibidores específicos para cada una de las familias de PLA2 y su posible utilización terapéutica. Las PLA2 son enzimas implicadas en procesos inflamatorios, en acciones enzimáticas que deterioran varios sistemas y en el proceso de transducción de señal intracelular. El potencial de intervención con fines de tratamiento es bastante amplio y los inhibidores diseñados en los últimos años han sido muy específicos ya que han tenido en cuenta las particularidades estructurales de cada familia de PLA2, las cuales hacen que tengan funciones muy diferentes entre cada una de ellas. Se pueden augurar la aparición de nuevos tratamientos para enfermedades de tipo metabólico como la diabetes, inflamatorios como la sepsis, enfermedades autoinmunes e infecciones por la inhibición de procesos de invasión de organismos intracelulares obligatorios

Alveolitis alergica extrinseca. (Un caso clinico). / Extrinsic allergic alveolitis. (A clinical case)

Se ha reconocido que la alveolitis alergica extrinseca y otros trastornos pulmonares, son consecuencia de reacciones de hipersensibilidad a antigenos organicos inhalados. En la mayoria de los casos pueden demostrarse anticuerpos precipitantes a antigenos organicos, estando implicado un mecanismo alergico tipo III, en la patogenia de dichos trastornos.Estas reacciones se han comparado a una reaccion de enfermedad del suero de las vias respiratorias en las que el antigeno es mas bien inhalado que inyectado. En una forma de estos trastornos la reaccion afeta principalmente al tejido pulmonar periferico, habiendo sido referida como alveolitis alergica extrinseca como en el caso presentado que se trata de un paciente de 6 anos, hijo de un criador de palomas en cuyo estudio inmunologico se evidenciaron por inmunodifusion, precipitinas al excremento y suero de paloma