Comparison of thermal, rheological properties of Finnish Pinus sp. and Brazilian Eucalyptus sp. black liquors and their impact on recovery units.

Black liquor (BL) is the major bioproduct and biomass fuel in pulp mill processes. However, the high viscosity of BL makes it a challenging material to work with, resulting in issues with evaporators and heat exchangers during its transport and processing. The thermal and rheological properties of BLs from Pinus sp. (PBL) and Eucalyptus sp. (EBL) were studied. FTIR spectra revealed the presence of the characteristic functional groups and the chemical composition in liquors. TGA/DTG curves showed three characteristic degradation stages related to evaporation of water, pyrolysis of organic groups, and condensation of char. Rheologically, liquors are classified as non-Newtonian and with comportment pseudoplastic. Their rheological dynamic shear properties included a linear viscoelastic region up to 1% shear strain, while frequency sweeps showed that storage modulus (G') > loss modulus (G''), thus confirming the solid-like behavior of both BLs. The rheological study demonstrated that increasing the temperature and oscillatory deformations of PBL and EBL decreased their degree of viscoelasticity, which could favor their pumping and handling within the pulp mill, as well as the droplet formation and swelling characteristics in the recovery furnace.

[Ingestion of multiple magnets in pediatrics: endoscopic or surgical emergency?] / Ingestión de múltiples imanes en pediatría: ¿emergencia endoscópica o quirúrgica?

Ingestion of foreign bodies is common in the pediatric population. Most foreign bodies have a benign behavior and are usually eliminated without generating greater morbidity and mortality. In relation to the intake of magnets, its frequency has increased to the point that it currently represents a public health problem in the pediatric population. The ingestion of a single magnet does not generate any risk, but the ingestion of 2 or more of these, or even of magnets and metals in succession is considered an emergency since they can attract each other and can cause serious symptoms of intestinal obstruction, bleeding, fistulas, perforation and even intestinal necrosis. We present 2 pediatric patients, who ingested multiple magnets, in these cases we highlight the variety in the clinical presentation, as well as the complications presented in relation to a late diagnosis.

Ingestión de múltiples imanes en pediatría: ¿emergencia endoscópica o quirúrgica?

La ingesta de cuerpos extraños es común en población pediátrica. La mayoría de cuerpos extraños tienen un comportamiento benigno y suelen ser eliminados sin generar mayor morbimortalidad. En relación a la ingesta de imanes, se ha incrementado su frecuencia, a tal punto que en la actualidad representa un problema de salud pública en población pediátrica. La ingesta de un solo imán no genera ningún riesgo, pero la ingestión de 2 o más de estos, o incluso de imanes y metales de forma sucesiva se considera una emergencia ya que estos pueden atraerse entre sí pudiendo provocar cuadros graves de obstrucción intestinal, sangrado, fístulas, perforación e incluso necrosis intestinal. Presentamos 2 pacientes en edad pediátrica, que ingirieron múltiples imanes, en estos casos resaltamos la variedad en la presentación clínica, así como las complicaciones presentadas en relación a un diagnóstico tardío.

Ingestion of foreign bodies is common in the pediatric population. Most foreign bodies have a benign behavior and are usually eliminated without generating greater morbidity and mortality. In relation to the intake of magnets, its frequency has increased to the point that it currently represents a public health problem in the pediatric population. The ingestion of a single magnet does not generate any risk, but the ingestion of 2 or more of these, or even of magnets and metals in succession is considered an emergency since they can attract each other and can cause serious symptoms of intestinal obstruction, bleeding, fistulas, perforation and even intestinal necrosis. We present 2 pediatric patients, who ingested multiple magnets, in these cases we highlight the variety in the clinical presentation, as well as the complications presented in relation to a late diagnosis.

Estado nutricional, síndrome metabólico e inflamación en pacientes con enfermedad de Chagas / Nutritional condition, metabolic syndrome and inflammation in patients with Chagas disease

El propósito de este estudio fue describir la asociación entre el estado nutricional, la presencia de síndrome metabólico (SM), y el estado inflamatorio, en pacientes con Enfermedad de Chagas (ECh), atendidos en la consulta externa del Instituto de Medicina Tropical en Caracas. El estudio fue de tipo transversal y correlacional, en el cual se seleccionaron 34 pacientes a los cuales se les realizó un diagnóstico parasitológico, inmunológico y molecular de la ECh. Se evaluaron variables antropométricas, clínicas y bioquímicas, así como el SM el cual fue determinado por los criterios del III Panel estadounidense para el Tratamiento de Adultos del Programa Nacional de Educación sobre el Colesterol (ATP-III, por sus siglas en inglés). Se encontró que la mayoría de los pacientes presentaron sobrepeso u obesidad (73,5%), un porcentaje de grasa corporal (% GC) alto o muy alto (82,3%), y obesidad abdominal (61,8 %). La frecuencia de SM fue de 29,4% y más del 90% mostraron valores elevados de Proteína C Reactiva ultrasensible (PCRus). Valores más elevados del IMC se asociaron con un estadio más avanzado de la ECh. Los sujetos con presencia de ADN de Tripanosoma cruzi (T. cruzi) circulante en sangre, presentaron mayor % GC, y en su mayoría, fueron diagnosticados con SM. En conclusión, los pacientes evaluados mostraron un exceso de adiposidad, que puede favorecer el estado inflamatorio, el desarrollo de SM y la progresión de la ECh(AU)

The purpose of the study was to describe the association between nutritional and inflammatory status and the presence of metabolic syndrome (MS) on patients with Chagas disease (CD) treated at the Outpatient Services of the Tropical Medicine Institute in Caracas, Venezuela. The study was cross-sectional and correlational. Thirty-four (34) patients were selected and a molecular, immunological, and parasitological diagnostic test was ran for Chagas disease. Anthropometric, clinic, and biochemical variables were evaluated, and the MS was determined using National Cholesterol Education Program Expert/Adult Treatment Panel III (ATP-III) criteria. The results showed a high percentage of patients overweight or presenting obesity (73.5%), a high and very high percentage of body fat (82.3%), and abdominal obesity (61.8%). The prevalence of MS was 29,4% and more than 90% of patients showed elevated values of high sensitivity C-reactive protein (hsCRP). Higher body-mass index values were associated with advanced stages of the CD. Subjects in the presence of T. cruzi DNA in the blood showed a greater percentage of body fat and, most of them, were diagnosed with MS. In conclusion, the evaluated patients showed an excess of adiposity which may favor an inflammatory status, the development of the MS, and the progress of the CD(AU)

Venezuela's humanitarian crisis, resurgence of vector-borne diseases, and implications for spillover in the region.

In the past 5-10 years, Venezuela has faced a severe economic crisis, precipitated by political instability and declining oil revenue. Public health provision has been affected particularly. In this Review, we assess the impact of Venezuela's health-care crisis on vector-borne diseases, and the spillover into neighbouring countries. Between 2000 and 2015, Venezuela witnessed a 359% increase in malaria cases, followed by a 71% increase in 2017 (411 586 cases) compared with 2016 (240 613). Neighbouring countries, such as Brazil, have reported an escalating trend of imported malaria cases from Venezuela, from 1538 in 2014 to 3129 in 2017. In Venezuela, active Chagas disease transmission has been reported, with seroprevalence in children (<10 years), estimated to be as high as 12·5% in one community tested (n=64). Dengue incidence increased by more than four times between 1990 and 2016. The estimated incidence of chikungunya during its epidemic peak is 6975 cases per 100 000 people and that of Zika virus is 2057 cases per 100 000 people. The re-emergence of many vector-borne diseases represents a public health crisis in Venezuela and has the possibility of severely undermining regional disease elimination efforts. National, regional, and global authorities must take action to address these worsening epidemics and prevent their expansion beyond Venezuelan borders.

Microbiota gastrointestinal aeróbica en niños con trastorno del espectro autista. Estudio preliminar / GASTROINTESTINAL MICROBIOTA AEROBIC IN CHILDREN WITH AUTISM SPECTRUM DISORDERS. PRELIMINARY STUDY

Introducción: la alteración de la microbiota intestinal o Dis- biosis ha sido implicada en los cambios de comportamiento del neurodesarrollo y problemas gastrointestinales en pacientes con trastorno del espectro autista (TEA). Objetivo: evaluar la micro- biota intestinal aeróbica (MGIA) y clasificarla en beneficiosa, transitoria y enteropatógena en niños con TEA en la Unidad de Autismo-Maternidad Concepción Palacios. Pacientes y métodos: desde el 26/02/2015 al 12/05/2015 se estudiaron de forma experimental y prospectiva 39 niños diagnosticados con TEA; en el estudio de la MGIA se utilizaron muestras de heces. Se aplicó una encuesta para recopilar datos epidemiológicos, clínicos y comportamientos del neurodesarrollo. Se propone la clasificación de severidad de la disbiosis en grado I,II,III o ausente para la evaluación de la MGIA. Resultados: Fueron 27 niños (69,23%) y 12 niñas (30,77%), con una edad media de 6,3. Disbiosis 31 (79,5%), Disbiosis ausente 8 (20,5%). Según el grado de disbiosis, 5 (16,13%) Grado I, 7 (22,58%) Grado II, 19 (61,29%) Grado III. Los principales agentes causales de disbiosis fueron Klebsiella spp. 16, Proteus mirabilis 8, Streptococcus sp, 6, Serratia marcensces 5, Candida spp. 4. Dos niños presentaron Campylobacter coli como MGIA patógena. Manifestaciones gastrointestinales: 25,80% dolor abdominal, 16,13% diarrea y 38.7% estreñimiento. Trastornos del neurodesarrollo: 50% aleteos, 34% autoagresión, 61% berrinches, insomnio un 34.3%. Conclusiones: Se hace necesario comparar esta investigación con un grupo de niños sin TEA para confirmar que la presencia de disbiosis como causante de alteración de la MGIA se presenta con más frecuencia en niños con TEA.

Background: altering the intestinal microbiota or Dysbiosis has been implicated in the changes the behavior of neurodevelopmen- tal and gastrointestinal problems in patients with autism spectrum disorder (ASD). Objective: To evaluate aerobic intestinal micro- biota (AMGI) and rank it beneficial, transitory and enteropathogenic in children with ASD, the Autism Unit-Maternidad Concepcion Palacios. Patients and Methods: From 26/02/2015 to 05/12/2015 were studied experimentally and prospectively 39 children diagnosed with ASD; in this study the AMGI stool samples were used. A survey to collect epidemiological, clinical and neurodevelopmental behavior was applied. Severity classification dysbiosis proposed in grade I, II, III or absent for evaluating the AMGI. Results: There were 27 kids (69.23%) and 12 girls (30.77%) with a mean age of 6.3. Dysbiosis 31 (79.5%), Dysbiosis absent eight (20.5%). Depending on the degree of dysbiosis, 5 (16.13%) Grade I, 7 (22.58%) Grade II, 19 (61.29%) Grade III. The main causative agents of dysbiosis were Klebsiella spp. 16, Proteus mirabilis 8, Streptococcus sp. 6, Serratia marcensces 5, Candida spp. 4. Two children presented MGIA pathogenic Campylobacter coli. Gastrointestinal symptoms: 25,80% abdominal pain, 16.13% diarrhea and 38.7% constipation. Neurodevelopmental disorders: 50% flapping, 34% self-harm, 61% tantrums and 34.3% insomnia. Conclusion: It is necessary to compare this research with a group of children without ASD to confirm the presence of dysbiosis to cau- se impaired MGIA occurs most often in children with ASD.

Panstrongylus geniculatus and four other species of triatomine bug involved in the Trypanosoma cruzi enzootic cycle: high risk factors for Chagas' disease transmission in the Metropolitan District of Caracas, Venezuela.

BACKGROUND: Chagas' disease is caused by the protozoan Trypanosoma cruzi and is autochthonous to the Americas. Its distribution depends on triatomine bugs that are responsible for the transmission of the disease. In 2005, we reported the presence of Panstrongylus geniculatus as a risk for Chagas' disease transmission in Caracas and neighboring areas. Three massive oral outbreaks occurred in the following years. Here we report the results of a 7-year study on triatomine species found in the Metropolitan District of Caracas (MDC), Venezuela. METHODS: Triatomine species collected by inhabitants of Caracas during 7 years were analyzed for parasite infection and blood meal. Triatomines were found in 31 of the 32 parishes surveyed. Traitomines were examined for the presence of blood and parasites in the digestive tract. Molecular techniques were used for the typing of parasites. RESULTS: A total of 3551 triatomines were captured from 31 of the 32 parishes surveyed. The vast majority of these were identified as P. geniculatus (98.96%), followed by Triatoma nigromaculata (0.59%), Triatoma maculata (0.39%) and Rhodnius prolixus (0.06%). Triatomines were always most abundant between April and June, and 2010 showed the highest number. We found that 54% of the specimens were females, 42.5% males and 3.5% nymphs. Overall, 75.2% of the insects were naturally infected with T. cruzi and 48.7% had fed on blood. Analysis of the adult forms showed that 60% of the females and 31.9 % of the males had blood in their stomachs, and 77.5% of the females and 73.3% of the males were naturally infected with T. cruzi. Nearly all, 99.6% of the T. cruzi isolates analyzed belonged to the TcI genotype. CONCLUSIONS: Blood-fed triatomine bugs infected with T. cruzi were distributed throughout Caracas. Four different species of triatomines were identified of which P. geniculatus was by far the most predominant. Our previous report of Eratyrus mucronatus raises the number of triatomine species in the MDC to 5. Dramatic modifications to the surrounding natural habitats have led to the establishment of a T. cruzi urban enzootic cycle, resulting in a high risk for Chagas' disease transmission in this capital city.

Molecular epidemiologic source tracking of orally transmitted Chagas disease, Venezuela.

Oral outbreaks of Chagas disease are increasingly reported in Latin America. The transitory presence of Trypanosoma cruzi parasites within contaminated foods, and the rapid consumption of those foods, precludes precise identification of outbreak origin. We report source attribution for 2 peri-urban oral outbreaks of Chagas disease in Venezuela via high resolution microsatellite typing.

Ethnopharmacological evaluation of Trichilia hirta L. as anticancer source in traditional medicine of Santiago de Cuba / Evaluación etnofarmacológica de Trichilia hirta como una fuente anticancer en la medicina tradicional de Santiago de Cuba

Trichilia hirta L. (Meliaceae) is traditionally used as antitumor source in Santiago de Cuba. Therefore, the aim of this study was to document and analyze the traditional medicinal use of this plant by cancer patients in Santiago de Cuba and to evaluate its antiproliferative activity on human normal and cancer cells. Cancer patients consuming Trichilia hirta extracts (Jubabán) were randomly selected and interviewed. The antiproliferative activity of a polysaccharide-rich fraction from leaves was evaluated against normal (MRC-5) and cancer cells (A-549, HeLa and Hep-2) by MTT assay. The study revealed that Trichilia hirta extracts are mainly used as anticancer source (46 percent. Moreover, the majority of cancer patients consuming Trichilia hirta extracts had carcinoma (86 percent). In particular, the most frequent were lung (26 percent) and prostate (18 percent) carcinoma. The majority (90 percent) of patients were consuming the extracts simultaneously, or after the chemotherapy and radiotherapy treatment. The polysaccharide-rich fraction showed antiproliferative activity against human lung cancer cells (A-549) and human cervix carcinoma (HeLa) cancer cells. However, no toxicity was observed in human normal fibroblasts (MRC-5). These results suggest that polysaccharide-rich fraction from Trichilia hirta contribute to the antitumor properties of this specie.

Trichilia hirta L. (Meliaceae) es tradicionalmente usada como recurso antitumoral en Santiago de Cuba. Por lo que, el objetivo de este estudio fue documentar y analizar el uso tradicional de esta planta por pacientes con cáncer en Santiago de Cuba y evaluar su actividad antiproliferativa sobre células humanas normales y tumorales. Pacientes con cáncer consumiendo los extractos de Trichilia hirta (jubabán) fueron aleatoriamente seleccionados y entrevistados. La actividad antiproliferativa de la fracción rica en polisacáridos de hojas fue evaluada en células normales (MRC-5) y en células tumorales (A-549, HeLa y Hep-2) a través del ensayo con MTT. El estudio reveló que los extractos de Trichilia hirta eran usados mayoritariamente como recurso antitumoral (46 por ciento). Además, la mayoría de los pacientes consumiendo extractos de Trichilia hirta presentaron carcinoma (86 por ciento). En particular, los más frecuentes fueron carcinomas de pulmón (26 por ciento) y próstata (18 por ciento). También la mayoría de los pacientes (90 por ciento) consumieron los extractos simultáneamente o después de tratamientos con quimioterapia y radioterapia. La fracción rica en polisacáridos mostró actividad antiproliferativa contra las células de cáncer de pulmón humano (A-549) y carcinoma de cerviz humano (HeLa). Sin embargo, no se observó toxicidad en fibroblastos humanos normales (MRC-5). Estos resultados sugieren que la fracción rica en polisacáridos de hojas de Trichilia hirta contribuye a la actividad antitumoral de esta especie.

Geographical distribution of Trypanosoma cruzi genotypes in Venezuela.

Chagas disease is an endemic zoonosis native to the Americas and is caused by the kinetoplastid protozoan parasite Trypanosoma cruzi. The parasite is also highly genetically diverse, with six discrete typing units (DTUs) reported TcI - TcVI. These DTUs broadly correlate with several epidemiogical, ecological and pathological features of Chagas disease. In this manuscript we report the most comprehensive evaluation to date of the genetic diversity of T. cruzi in Venezuela. The dataset includes 778 samples collected and genotyped over the last twelve years from multiple hosts and vectors, including nine wild and domestic mammalian host species, and seven species of triatomine bug, as well as from human sources. Most isolates (732) can be assigned to the TcI clade (94.1%); 24 to the TcIV group (3.1%) and 22 to TcIII (2.8%). Importantly, among the 95 isolates genotyped from human disease cases, 79% belonged to TcI - a DTU common in the Americas, however, 21% belonged to TcIV- a little known genotype previously thought to be rare in humans. Furthermore, were able to assign multiple oral Chagas diseases cases to TcI in the area around the capital, Caracas. We discuss our findings in the context of T. cruzi DTU distributions elsewhere in the Americas, and evaluate the impact they have on the future of Chagas disease control in Venezuela.

Infección por Trypanosoma cruzi y polimorfismo del Citocromo B del ADN mitocondrial en Triatoma maculata de Anzoategui y Portuguesa, Venezuela / Trypanosoma cruzi infection and cytochrome b polimorphism of mitochondrial dna in Triatoma maculata of Anzoátegui and Portuguesa states, Venezuela

Con el fin de entender la dinámica poblacional de Triatoma maculata, se analizó el polimorfismo genético y los índices de infección con Trypanosoma cruzi, utilizando triatominos provenientes de ecotopos y regiones geográficas diferentes. El índice de infección parasitaria para T. maculata, fue de 29.8% a través de la observación directa al microscopio y 40.3% utilizando el método de reacción en cadena de la polimerasa. Los niveles de infección encontrados incrementan la importancia de T. maculata como vector involucrado en el ciclo de transmisión de T. cruzi. El análisis del polimorfismo de longitud de fragmentos de restricción de una región del gen Cyt B, permitió establecer en forma preliminar, diferencias en los patrones de bandas de este gen, según el origen geográfico de cada población. Esto puede asociarse a cambios relacionados con procesos adaptativos involucrados en la colonización de nuevos hábitats. No se observó variación genética para vectores capturados en diferentes ecotopos de una misma localidad. Sin embargo es evidente la participación del vector en el ciclo de transmisión, mostrando que la presencia de T. maculata en las casas no puede ser ignorada

In order to understand more about the populational dynamics of Triatoma maculata, the genetic polimorphism and the infection indexes of Trypanosoma cruzi were analysed, using triatomine obtained from different ecotopes and geographical regions. The parasitic infection index of T. maculata was 29.8% using the microscope direct observation, and 40.3% by the polymerase chain reaction method. Both methods were important for epidemiological screening of the vectors with low potential of infection. The amplification of one region the Cyt B gene of these organisms, followed by a restriction fragments length polymorphism analysis, allowed us to establish different patterns of bands according to the geographic origin of each population, which indicates the lack of migration between individuals of Portuguesa and Anzoátegui states. These genetic differences may be associated with changes in adaptative events involved in the colonization of new habitats. The lack of polymorphism among vectors collected in different habitats of the same region showed an important genetic flow which has epidemiological implications in the risk of transmission of the disease, showing that the presence of T. maculata in houses cannot be ignored

Identificación de una secuencia de ADN genómico de Leishmania especifica del subgénero Leishmania / Identification of a genomic DNA sequence of Leishmania, specific of Leishmania subgenus

Leishmania es el agente causante de la compleja enfermedad conocida como leishmaniasis. Las distintas especies de este parásito protozoario se encuentran agrupadas en dos subgéneros, Viannia y Leishmania, de acuerdo a su desarrollo en el mosquito vector. Un ensayo de PCR, β500-PCR, específico del subgénero Viannia, ha sido desarrollado utilizando la secuencia de ADN genómico denominada β500. En este trabajo se presenta el aislamiento e identificación de una secuencia genómica de 280 pb, L280, a partir del ADN genómico de Leishmania (Leishmania) mexicana luego de aplicar el ensayo β500-PCR en condiciones de baja rigurosidad. La secuenciación parcial de L280 permitió diseñar un ensayo de PCR (L280-PCR) que generó un producto de amplificación de 260 pb, en distintas condiciones de rigurosidad, cuando se utilizó el ADN genómico de distintas especies pertenecientes al subgénero Leishmania. El ensayo L280-PCR resultó negativo para el ADN genómico de distintas especies del subgénero Viannia al igual que para el ADN de otros organismos kinetoplastidos o humano. Los resultados sugieren que el ensayo L280-PCR es específico del subgénero Leishmania.

Leishmania is the causal agent of the leishmaniasis disease. The different species of this protozoa parasite are grouped in two subgenera, Viannia and Leishmania, according to their development in the sandfly vector. A specific PCR assay, β500-PCR, has been developed for the Viannia subgenus using the genomic β500 DNA sequence. In the present work we present the isolation and identification of a genomic sequence of 280 bp, L280, obtained from genomic DNA of Leishmania (Leishmania) mexicana after application of the β500-PCR assay at low stringency. After partial sequencing of L280 a PCR assay was generated, L280-PCR, this yielded a product of 260 bp at different conditions of stringency, when genomic DNA of different species of Leishmania subgenus was used. The L280-PCR assay was negative to genomic DNA of species belonging to the Viannia subgenus and also to other kinetoplastid organisms and human. The results suggest specificity of the L280-PCR assay for the Leishmania subgenus.

Cornea as a tissue reservoir of Trypanosoma cruzi.

Trypanosoma cruzi causal agent of Chagas' disease is a paninfective parasite of mammals transmitted through skin fecal contamination by Triatominae vectors. Studies of alternative routes for infection are scarce; therefore, eye infection should be important, because of the eye's high blood irrigation and brain proximity, as port of entry of the parasite. Trypanosoma cruzi parasites and/or their genetic material in ocular and adjacent muscle tissues were studied in batches of six NMRI mice (15 g) and Trichomys apereoides, an ancient caviomorph (250 g) inoculated with T. cruzi metacyclics from Brazilian (2) and Venezuelan (3) isolates genetically typified as T. cruzi I and II. Two animals/batch in the acute or chronic phase were killed and necropsies of cardiac and skeletal muscles, eyeball, and surrounding ocular muscle were processed for hematoxylin-eosine staining. Tissue parasitism was determined. DNA of the digested sections of the eyeball (5-10 mum) was extracted for T. cruzi k-DNA amplification by PCR, with S35 and S36 primers. The PCR products were analyzed. The average of maximum values of parasitemia of all infected animals was of 10(5) trypomastigotes/ml blood. Skeletal muscle and heart were colonized in patent infection for all isolates. Amastigote nests were found in corneal tissue of 2/3 of the used isolates and adjacent ocular muscle and connective tissue were parasitized. Trypanosoma cruzi k-DNA (330-bp band) was observed in ocular tissue of 4/6 of the isolates studied in both animal models. Investigations concerning infection of the eye globe tissues by T. cruzi are extremely scarce. The presence of stages of T. cruzi and/or its genetic products in ocular tissues indicate a broad colonization from a systemic infection. The results show the ocular environment as a possible appropriate microniche for T. cruzi and emphasize the risk of transmitting T. cruzi by ocular fluids and by parasitized cornea through transplants.

Mixed domestic infestation by Rhodnius prolixus Stal, 1859 and Panstrongylus geniculatus Latreille, 1811, vector incrimination, and seroprevalence for Trypanosoma cruzi among inhabitants in El Guamito, Lara State, Venezuela.

Mixed infestation of nymphs and adults of Rhodnius prolixus Stal, 1859 and Panstrongylus geniculatus Latreille, 1811 was detected in 3 (15%) of 20 dwellings in El Guamito, an endemic focus of Chagas disease in Lara State, Venezuela. In one of the houses, both species were positive for Trypanosoma cruzi: 14.3% (R. prolixus) and 20% (P. geniculatus ). The overall infection rate in 143 of 352 R. prolixus was 16.1%. Parasites isolated from R. prolixus were identified as T. cruzi I by random amplified polymorphic DNA analysis. Dot-enzyme-linked immunosorbent assays of 36 R. prolixus showed that 58.3% of the R. prolixus had fed on humans. The gut contents of one fifth-instar nymph of P. geniculatus that was positive for T. cruzi also reacted with anti-human serum. A questionnaire was used to gather data on the demographic and socioeconomic characteristics of the population. An indirect immunofluorescent test, an indirect hemaglutination test, and an ELISA were used to detect the presence of antibodies against T. cruzi in 84 of 86 inhabitants and in 15.5% of people more than 20 years old. The relative risk (RR) of infection was greater in men than in women (RR = 1.61, 95% confidence interval = 0.54-4.80). Of the people more than 15 years old, 36.6% had no formal education. All respondents recognized triatomine bugs, but they did not relate them to Chagas disease transmission. A total of 85.7% of the houses were "ranchos" suitable for the colonization of triatomine bugs. The possible domiciliation of P. geniculatus and the implications of competition with R. prolixus for resources are discussed. Since there is no clear separation of food sources, abiotic factors such as microclimatic variation within houses may be critical to predict the outcome of the process of competition and potential domestication of this generally sylvatic species.

Trypanosoma cruzi in a caviomorph rodent: parasitological and pathological features of the experimental infection of Trichomys apereoides (Rodentia, Echimyidae).

To understand the interaction of Trypanosoma cruzi with caviomorph rodents, which supposedly have an ancient co-evolutionary history with this parasite, experimental infection of laboratory reared Trichomys apereoides with several isolates of both genotypes of the parasite was studied. Parasitemia, pattern of hematic cells, specific humoral immune response, histopathological features and parasite clearance were appraised. T. apereoides maintained stable infections independent of the T. cruzi genotype as demonstrated by positive PCR results in analyses of several tissues after a 5 months follow-up. The acute phase was characterized by abundant and disseminated presence of amastigotes, vacuolization and/or myocytolysis. Lymphocytosis was a common feature. The chronic phase was characterized mainly by lymphomacroeosinophilic infiltrates independent of the inoculated T. cruzi isolate. T. cruzi of different genotypes did not show any tissular preference in T. apereoides.

Perfusion pediatrica / Pediatric perfusion

La incidencia de enfermedad cardíaca congénita es de 8 por ciento por cada 1000 nacidos vivos. El 90 por ciento son CIV, CÍA, Ductus, estenosis pulmonar y coartación aórtica. En algunos es indispensable el uso de la Circulación Extracorpórea para su corrección quirúrgica (1). En la Clínica San Rafael, 159 pacientes han sido intervenidos entre enero de 1996 y octubre de 2000, 83 niños y 76 niñas, en edades entre los 9 días y los 17 años, con una media de 6 años. Los tipos de corrección fueron: cierre de ductus arteriosos persistente, cierre de comunicaciones inter-auriculares (CIA), cierre de comunicaciones inter-ventriculares (CIV), coartación aórtica, fístula sistémico pulmonar, Fallot, cambio válvula mitral, cambio válvula aórtica, plastia válvula aórtica, plastia válvula tricúspide, plastia válvula pulmonar, canal aurículo-ventricular, doble salida de ventrículo derecho, transposición de grandes vasos, drenaje venoso anómalo, tumor del ventrículo izquierdo. En todos los pacientes se aplicó el protocolo establecido en nuestra Institución, siendo el perfusionista quien seleccionó el oxigenador, el circuito, las cánulas, el hemoconcentrador pediátrico y la purga. La experiencia adquirida en la Clínica San Rafael ha permitido realizar intervenciones de cardiopatías complejas con buenos resultados. La Técnica de Perfusión, es muy importante en el resultado de la intervención, haciendo que ésta sea segura y fiable

Valoración de un método de evaluación final diferente en la Licenciatura en Enfermería / Assessesment of a different final evaluation method in Baccalaureate Nursing

Se desarrolla por primera vez en el país un método de evaluación final diferente, en el curso 1993-1994 en la Facultad de Ciencias Médicas de Cienfuegos, en la especialidad de Licenciatura en Enfermería. Se realizó un estudio descriptivo y retrospectivo y se aplicó en los 3 primeros años al 100 por ciento de la matrícula en las asignaturas de Enfermería General II, IV y VI, con el propósito de valorar el cumplimiento de los objetivos a alcanzar en cada nivel, comparar los resultados de este método con el índice académico, pronóstico, método tradicional, clasificación final e identificar los criterios de estudiantes y profesores en relación con el método. Se elaboraron los instrumentos metodológicos correspondientes pruebas de medición de conocimientos para garantizar el éxito del método. Se aplicaron encuestas a estudiantes y profesores para determinar la factibilidad del mismo. Esto nos permitió evaluar en 22 horas a 228 estudiantes, mientras que en el método tradicional se requiere de 90 horas, evaluando aproximadamente la mitad de los objetivos. Entre las ventajas de este nuevo método está evaluar un mayor número de objetivos en menor tiempo, a los estudiantes con las mismas situaciones y a los profesores. La calificación es más rápida que en el examen tradicional, por lo que resulta cualitativamente superior al método

Aspectos ultraestructurales de la penetracion de lantano en vesicula biliar de cobayo en funcion del flujo de absorción de agua / Ultrastructural aspects of the lanthanum penetration in guinea gallbladder in function of the absorption flow water

Hay controversias sobre si el agua atraviesa la vía paracelular en epitelios de baja resistencia (por ejemplo, vesícula biliar). El objetivo de este trabajo es por tanto, estudiar una posible correlación entre el flujo de absorción de volumen (Jv) y la penetración del ión La3+ usando fluidos de diferentes osmolalidades, lo cual permite variar Jv. Vesículas biliares de cobayo se perfundieron in vitro a pH y temperatura fisiológicos con fluidos oxigenados a dos osmolalidades: 300 mOsm/Kg (isosmótico) y 100 mOsm/Kg (hiposmótico) que contenían dos concentraciones de La3+1 y 10mM para cada osmolalidad y se prepararon para estudios de microscopía electrónica de transmisión. Después se procedió a evaluar el grado de pentración del La3+ cuantificando el número de uniones penetradas por el marcador y la longitud de su recorrido dentro del espacio intercelular (en *m), el trayecto se midió comenzando en el borde apical y en dirección latero-basal. Jv se duplica en la condición hiposmótica y en las micrografías se aprecia mayor grado de penetración del La3+ por las vías paracelulares en las vesículas con mayor flujo de volumen. Hay ausencia de precipitados de La3+ en el citoplasma, el cual está satisfactoriamente preservado, aun a 100 mOsm/Kg, lo que muestra que la integridad de la membrana plasmática se mantiene. Esto indica que la penetración del La3+ varía con Jv. Los resultados obtenidos constituyen una evidencia para afirmar que la penetración de La3+ varía con Jv y que una fracción de este último se cumple a través de las vías paracelulares